Search results for: food samples

Authors: A. Delimitsou, C. Gouedard, E. Konstanta, A. Koletis, S. Patera, E. Manou, K. Spaho, S. Murray

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Background: There remains a lack of International Standard Control Reference materials for Next Generation Sequencing-based approaches or device calibration. We have designed and validated dsDNA biomimetic reference materials for targeted such approaches incorporating proprietary motifs (patent pending) for device/test calibration. They enable internal single-sample calibration, alleviating sample comparisons to pooled historical population-based data assembly or statistical modelling approaches. We have validated such an approach for BRCA Copy Number Variation analytics using iQRS™-CNVSUITE versus Mixed Ligation-dependent Probe Amplification. Methods: Standard BRCA Copy Number Variation analysis was compared between mixed ligation-dependent probe amplification and next generation sequencing using a cohort of 198 breast/ovarian cancer patients. Next generation sequencing based copy number variation analysis of samples spiked with iQRS™ dsDNA biomimetics were analysed using proprietary CNVSUITE software. Mixed ligation-dependent probe amplification analyses were performed on an ABI-3130 Sequencer and analysed with Coffalyser software. Results: Concordance of BRCA – copy number variation events for mixed ligation-dependent probe amplification and CNVSUITE indicated an overall sensitivity of 99.88% and specificity of 100% for iQRS™-CNVSUITE. The negative predictive value of iQRS-CNVSUITE™ for BRCA was 100%, allowing for accurate exclusion of any event. The positive predictive value was 99.88%, with no discrepancy between mixed ligation-dependent probe amplification and iQRS™-CNVSUITE. For device calibration purposes, precision was 100%, spiking of patient DNA demonstrated linearity to 1% (±2.5%) and range from 100 copies. Traditional training was supplemented by predefining the calibrator to sample cut-off (lock-down) for amplicon gain or loss based upon a relative ratio threshold, following training of iQRS™-CNVSUITE using spiked iQRS™ calibrator and control mocks. BRCA copy number variation analysis using iQRS™-CNVSUITE™ was successfully validated and ISO15189 accredited and now enters CE-IVD performance evaluation. Conclusions: The inclusion of a reference control competitor (iQRS™ dsDNA mimetic) to next generation sequencing-based sequencing offers a more robust sample-independent approach for the assessment of copy number variation events compared to mixed ligation-dependent probe amplification. The approach simplifies data analyses, improves independent sample data analyses, and allows for direct comparison to an internal reference control for sample-specific quantification. Our iQRS™ biomimetic reference materials allow for single sample copy number variation analytics and further decentralisation of diagnostics to single patient sample assessment.

Keywords: validation, diagnostics, oncology, copy number variation, reference material, calibration

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Authors: Abdullah S. Alghamdi, Khaled Alghamdi, Richard O. Jenkins, Parvez I. Haris

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Background: Quantity and quality of sleep have been reported to be significant risk factors for obesity and development of metabolic disorders such as type 2 diabetes mellitus (T2DM). The relationship between diabetes and sleep quantity was reported to be U-shaped, which means increased or decreased sleeping hours can increase the risk of diabetes. The plasma glucagon levels were found to continuously decrease during night-time sleep in healthy individuals, independently of blood glucose and insulin levels. The disturbance of the circadian rhythm is also important and has been linked with an increased the chance of diabetes incidence. There is a lack of research on sleep patterns on Saudis with T2DM and how this is affected by Ramadan fasting. Aim: To assess the sleeping patterns of Saudis with T2DM (before, during, and after Ramadan), using two different techniques and relate this to their HbA1c levels. Method: This study recruited 82 Saudi with T2DM, who chose to fast during Ramadan, from the Endocrine and Diabetic Centre of Al Iman General Hospital, Riyadh, Saudi Arabia. Ethical approvals for the study were obtained from De Montfort University and Saudi Ministry of Health. Their sleeping patterns were assessed by a self-administered questionnaire (before, during, and after Ramadan). The assessment included the daily total sleeping hours (DTSH), and total night-time sleeping hours (TNTSH) of the participants. In addition, sleeping patterns of 36 patients, randomly selected from the 82 participants, were further tracked during and after Ramadan by using Fitbit Flex 2™ accelerometer. Blood samples were collected in each period for measuring HbA1c. Results: Questionnaire analysis revealed that the sleeping patterns significantly changed between the periods, with shorter hours during Ramadan (P < 0.001 for DTSH, and P < 0.001 for TNTSH). These findings were confirmed by the Fitbit data, which also indicated significant shorter sleeping hours for the DTSH, and the TNTSH during Ramadan (P < 0.001 and P < 0.001, respectively). Although there were no significant correlations between the questionnaire and Fitbit data, the TNTSH were shorter among the participants in all periods by both techniques. The mean HbA1c significantly varied between periods, with lowest level during Ramadan. Although the statistical tests did not show significant variances in the mean HbA1c between the groups of participants regarding their hours of sleeping, the lowest mean HbA1c was observed in the group of participants who slept for 6-8 hours and had longer night-time sleeping hours. Conclusion: A short sleep duration, and absence of night-time sleep were significantly observed among the majority of the study population during Ramadan, which could suppress the full benefits of Ramadan fasting for diabetic patients. This study showed that there is a good agreement between the findings of the questionnaire and the Fitbit device for evaluating sleeping patterns in a Saudi population. A larger study is needed in the future to investigate the impact of Ramadan fasting on sleep quality and quantity and its relationship with health and disease.

Keywords: Diabetes, Fasting, Fitbit, HbA1c, IPAQ, Ramadan, Sleep

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Authors: Ashok Kumar, Shiv Brat Singh, Kalyan Kumar Ray

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There is growing awareness to design steels against fatigue damage Ferrite martensite dual-phase steels are known to exhibit favourable mechanical properties like good strength, ductility, toughness, continuous yielding, and high work hardening rate. However, dual-phase steels containing bainite as second phase are potential alternatives for ferrite martensite steels for certain applications where good fatigue property is required. Fatigue properties of dual phase steels are popularly assessed by the nature of variation of crack growth rate (da/dN) with stress intensity factor range (∆K), and the magnitude of fatigue threshold (∆Kth) for long cracks. There exists an increased emphasis to understand not only the long crack fatigue behavior but also short crack growth behavior of ferrite bainite dual phase steels. The major objective of this report is to examine the influence of microstructures on the short and long crack growth behavior of a series of developed dual-phase steels with varying amounts of bainite and. Three low carbon steels containing Nb, Cr and Mo as microalloying elements steels were selected for making ferrite-bainite dual-phase microstructures by suitable heat treatments. The heat treatment consisted of austenitizing the steel at 1100°C for 20 min, cooling at different rates in air prior to soaking these in a salt bath at 500°C for one hour, and finally quenching in water. Tensile tests were carried out on 25 mm gauge length specimens with 5 mm diameter using nominal strain rate 0.6x10⁻³ s⁻¹ at room temperature. Fatigue crack growth studies were made on a recently developed specimen configuration using a rotating bending machine. The crack growth was monitored by interrupting the test and observing the specimens under an optical microscope connected to an Image analyzer. The estimated crack lengths (a) at varying number of cycles (N) in different fatigue experiments were analyzed to obtain log da/dN vs. log °∆K curves for determining ∆Kthsc. The microstructural features of these steels have been characterized and their influence on the near threshold crack growth has been examined. This investigation, in brief, involves (i) the estimation of ∆Kthsc and (ii) the examination of the influence of microstructure on short and long crack fatigue threshold. The maximum fatigue threshold values obtained from short crack growth experiments on various specimens of dual-phase steels containing different amounts of bainite are found to increase with increasing bainite content in all the investigated steels. The variations of fatigue behavior of the selected steel samples have been explained with the consideration of varying amounts of the constituent phases and their interactions with the generated microstructures during cyclic loading. Quantitative estimation of the different types of fatigue crack paths indicates that the propensity of a crack to pass through the interfaces depends on the relative amount of the microstructural constituents. The fatigue crack path is found to be predominantly intra-granular except for the ones containing > 70% bainite in which it is predominantly inter-granular.

Keywords: bainite, dual phase steel, fatigue crack growth rate, long crack fatigue threshold, short crack fatigue threshold

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Authors: Jiujie Cai, Fengxia LI, Haibo Wang

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After years of research, offshore oil and gas development now are shifted to unconventional reservoirs, where multi-stage hydraulic fracturing technology has been widely used. However, the simulation of complex hydraulic fractures in tight reservoirs is faced with geological and engineering difficulties, such as large burial depths, sand-shale interbeds, and complex stress barriers. The objective of this work is to simulate the hydraulic fracture propagation in the tight sandstone matrix of the marine-continental transitional reservoirs, where the Shanxi Formation in Tianhuan syncline of the Dongsheng gas field was used as the research target. The characteristic parameters of the vertical rock samples with rich beddings were clarified through rock mechanics experiments. The influence of rock mechanical parameters, vertical stress difference of pay-zone and bedding layer, and fracturing parameters (such as injection rates, fracturing fluid viscosity, and number of perforation clusters within single stage) on fracture initiation and propagation were investigated. In this paper, a 3-D fracture propagation model was built to investigate the complex fracture propagation morphology by boundary element method, considering the strength of bonding surface between layers, vertical stress difference and fracturing parameters (such as injection rates, fluid volume and viscosity). The research results indicate that on the condition of vertical stress difference (3 MPa), the fracture height can break through and enter the upper interlayer when the thickness of the overlying bedding layer is 6-9 m, considering effect of the weak bonding surface between layers. The fracture propagates within the pay zone when overlying interlayer is greater than 13 m. Difference in fluid volume distribution between clusters could be more than 20% when the stress difference of each cluster in the segment exceeds 2MPa. Fracture cluster in high stress zones cannot initiate when the stress difference in the segment exceeds 5MPa. The simulation results of fracture height are much higher if the effect of weak bonding surface between layers is not involved. By increasing the injection rates, increasing fracturing fluid viscosity, and reducing the number of clusters within single stage can promote the fracture height propagation through layers. Optimizing the perforation position and reducing the number of perforations can promote the uniform expansion of fractures. Typical curves of fracture height estimation were established for the tight sandstone of the Lower Permian Shanxi Formation. The model results have good consistency with micro-seismic monitoring results of hydraulic fracturing in Well 1HF.

Keywords: fracture propagation, boundary element method, fracture height, offshore oil and gas, marine-continental transitional reservoirs, rock mechanics experiment

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Authors: Eduardo Antonio Lozano Hernandez, Nancy Ramirez Alvarez, Lorena Margarita Rios Mendoza, Jose Vinicio Macias Zamora, Felix Augusto Hernandez Guzman, Jose Luis Sanchez Osorio

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Microplastics (MPs) are one of the most numerous reported wastes found in the marine ecosystem, representing one of the greatest risks for organisms that inhabit that environment due to their bioavailability. Such is the case of bivalve mollusks, since they are capable of filtering large volumes of water, which increases the risk of contamination by microplastics through the continuous exposure to these materials. This study aims to determine, quantify and characterize microplastics found in the cultured oyster Crassostrea gigas. We also analyzed if there are spatio-temporal differences in the microplastic concentration of organisms grown in two bays having quite different human population. In addition, we wanted to have an idea of the possible impact on humans via consumption of these organisms. Commercial size organisms (>6cm length; n = 15) were collected by triplicate from eight oyster farming sites in Baja California, Mexico during winter and summer. Two sites are located in Todos Santos Bay (TSB), while the other six are located in San Quintin Bay (SQB). Site selection was based on commercial concessions for oyster farming in each bay. The organisms were chemically digested with 30% KOH (w/v) and 30% H₂O₂ (v/v) to remove the organic matter and subsequently filtered using a GF/D filter. All particles considered as possible MPs were quantified according to their physical characteristics using a stereoscopic microscope. The type of synthetic polymer was determined using a FTIR-ATR microscope and using a user as well as a commercial reference library (Nicolet iN10 Thermo Scientific, Inc.) of IR spectra of plastic polymers (with a certainty ≥70% for polymers pure; ≥50% for composite polymers). Plastic microfibers were found in all the samples analyzed. However, a low incidence of MP fragments was observed in our study (approximately 9%). The synthetic polymers identified were mainly polyester and polyacrylonitrile. In addition, polyethylene, polypropylene, polystyrene, nylon, and T. elastomer. On average, the content of microplastics in organisms were higher in TSB (0.05 ± 0.01 plastic particles (pp)/g of wet weight) than found in SQB (0.02 ± 0.004 pp/g of wet weight) in the winter period. The highest concentration of MPs found in TSB coincides with the rainy season in the region, which increases the runoff from streams and wastewater discharges to the bay, as well as the larger population pressure (> 500,000 inhabitants). Otherwise, SQB is a mainly rural location, where surface runoff from streams is minimal and in addition, does not have a wastewater discharge into the bay. During the summer, no significant differences (Manne-Whitney U test; P=0.484) were observed in the concentration of MPs found in the cultured oysters of TSB and SQB, (average: 0.01 ± 0.003 pp/g and 0.01 ± 0.002 pp/g, respectively). Finally, we concluded that the consumption of oyster does not represent a risk for humans due to the low concentrations of MPs found. The concentration of MPs is influenced by the variables such as temporality, circulations dynamics of the bay and existing demographic pressure.

Keywords: FTIR-ATR, Human risk, Microplastic, Oyster

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Authors: K. Rhea Devaiah, B. S. Premalatha

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Background: Tonsillar Lingual sulcus is the area between the tonsils and the base of the tongue. The surgical resection of the lesions in the head and neck results in changes in speech and swallowing functions. The severity of the speech and swallowing problem depends upon the site and extent of the lesion, types and extent of surgery and also the flexibility of the remaining structures. Need of the study: This paper focuses on the importance of speech and swallowing rehabilitation in an individual with the lesion in the Tonsillar Lingual Sulcus and post-operative functions. Aim: Evaluating the speech and swallow functions post-intensive speech and swallowing rehabilitation. The objectives are to evaluate the speech intelligibility and swallowing functions after intensive therapy and assess the quality of life. Method: The present study describes a report of an individual aged 47years male, with the diagnosis of basaloid squamous cell carcinoma, left tonsillar lingual sulcus (pT2n2M0) and underwent wide local excision with left radical neck dissection with PMMC flap reconstruction. Post-surgery the patient came with a complaint of reduced speech intelligibility, and difficulty in opening the mouth and swallowing. Detailed evaluation of the speech and swallowing functions were carried out such as OPME, articulation test, speech intelligibility, different phases of swallowing and trismus evaluation. Self-reported questionnaires such as SHI-E(Speech handicap Index- Indian English), DHI (Dysphagia handicap Index) and SESEQ -K (Self Evaluation of Swallowing Efficiency in Kannada) were also administered to know what the patient feels about his problem. Based on the evaluation, the patient was diagnosed with pharyngeal phase dysphagia associated with trismus and reduced speech intelligibility. Intensive speech and swallowing therapy was advised weekly twice for the duration of 1 hour. Results: Totally the patient attended 10 intensive speech and swallowing therapy sessions. Results indicated misarticulation of speech sounds such as lingua-palatal sounds. Mouth opening was restricted to one finger width with difficulty chewing, masticating, and swallowing the bolus. Intervention strategies included Oro motor exercise, Indirect swallowing therapy, usage of a trismus device to facilitate mouth opening, and change in the food consistency to help to swallow. A practice session was held with articulation drills to improve the production of speech sounds and also improve speech intelligibility. Significant changes in articulatory production and speech intelligibility and swallowing abilities were observed. The self-rated quality of life measures such as DHI, SHI and SESE Q-K revealed no speech handicap and near-normal swallowing ability indicating the improved QOL after the intensive speech and swallowing therapy. Conclusion: Speech and swallowing therapy post carcinoma in the tonsillar lingual sulcus is crucial as the tongue plays an important role in both speech and swallowing. The role of Speech-language and swallowing therapists in oral cancer should be highlighted in treating these patients and improving the overall quality of life. With intensive speech-language and swallowing therapy post-surgery for oral cancer, there can be a significant change in the speech outcome and swallowing functions depending on the site and extent of lesions which will thereby improve the individual’s QOL.

Keywords: oral cancer, speech and swallowing therapy, speech intelligibility, trismus, quality of life

Procedia PDF Downloads 106

Authors: Safaa M. Hassan; Safwat S. Gabr, Mohamed F. Sadek

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This study is proposed for the lithological and iron oxides detection in the old mine areas of El-Bahariya Depression, Western Desert, using ASTER and Landsat-8 remote sensing data. Four old iron ore occurrences, namely; El-Gedida, El-Haraa, Ghurabi, and Nasir mine areas found in the El-Bahariya area. This study aims to find new high potential areas for iron mineralization around El-Baharyia depression. Image processing methods such as principle component analysis (PCA) and band ratios (b4/b5, b5/b6, b6/b7, and 4/2, 6/7, band 6) images were used for lithological identification/mapping that includes the iron content in the investigated area. ASTER and Landsat-8 visible and short-wave infrared data found to help mapping the ferruginous sandstones, iron oxides as well as the clay minerals in and around the old mines area of El-Bahariya depression. Landsat-8 band ratio and the principle component of this study showed well distribution of the lithological units, especially ferruginous sandstones and iron zones (hematite and limonite) along with detection of probable high potential areas for iron mineralization which can be used in the future and proved the ability of Landsat-8 and ASTER data in mapping these features. Minimum Noise Fraction (MNF), Mixture Tuned Matched Filtering (MTMF), pixel purity index methods as well as Spectral Ange Mapper classifier algorithm have been successfully discriminated the hematite and limonite content within the iron zones in the study area. Various ASTER image spectra and ASD field spectra of hematite and limonite and the surrounding rocks are compared and found to be consistent in terms of the presence of absorption features at range from 1.95 to 2.3 μm for hematite and limonite. Pixel purity index algorithm and two sub-pixel spectral methods, namely Mixture Tuned Matched Filtering (MTMF) and matched filtering (MF) methods, are applied to ASTER bands to delineate iron oxides (hematite and limonite) rich zones within the rock units. The results are validated in the field by comparing image spectra of spectrally anomalous zone with the USGS resampled laboratory spectra of hematite and limonite samples using ASD measurements. A number of iron oxides rich zones in addition to the main surface exposures of the El-Gadidah Mine, are confirmed in the field. The proposed method is a successful application of spectral mapping of iron oxides deposits in the exposed rock units (i.e., ferruginous sandstone) and present approach of both ASTER and ASD hyperspectral data processing can be used to delineate iron-rich zones occurring within similar geological provinces in any parts of the world.

Keywords: Landsat-8, ASTER, lithological mapping, iron exploration, western desert

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Authors: Anupalli Roja Rani, Pavithra Dasari

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Background: Among several, breast cancer has emerged as the most common female cancer in developing countries. It is the most common cause of cancer-related deaths worldwide among women. It is a molecularly and clinically heterogeneous disease. Moreover, it is a hormone–dependent tumor in which estrogens can regulate the growth of breast cells by binding with estrogen receptors (ERs). Moreover, the use of natural products in cancer therapeutics is due to their properties of biocompatibility and less toxicity. Plants are the vast reservoirs for various bioactive compounds. Coleus barbatus (Lamiaceae) contains anticancer properties against several cancer cell lines. Method: In the present study, an attempt is being made to enrich the knowledge of the anticancer activity of pure compounds extracted from Coleus barbatus (Andrew). On human breast cancer cell lines MCF-7. Here in, we are assessing the antiproliferative activity of Coleus barbatus (Andrew) plant extracts against MCF 7 and also evaluating their toxicity in normal human mammary cell lines such as Human Mammary Epithelial Cells (HMEC). The active fraction of plant extract was further purified with the help of Flash chromatography, Medium Pressure Liquid Chromatography (MPLC) and preparative High-Performance Liquid Chromatography (HPLC). The structure of pure compounds will be elucidated by using modern spectroscopic methods like Nuclear magnetic resonance (NMR), Electrospray Ionisation Mass Spectrometry (ESI-MS) methods. Later, the growth inhibition morphological assessment of cancer cells and cell cycle analysis of purified compounds were assessed using FACS. The growth and progression of signaling molecules HER2, GRP78 was studied by secretion assay using ELISA and expression analysis by flow cytometry. Result: Cytotoxic effect against MCF-7 with IC50 values were derived from dose response curves, using six concentrations of twofold serially diluted samples, by SOFTMax Pro software (Molecular device) and respectively Ellipticine and 0.5% DMSO were used as a positive and negative control. Conclusion: The present study shows the significance of various bioactive compounds extracted from Coleus barbatus (Andrew) root material. It acts as an anti-proliferative and shows cytotoxic effects on human breast cancer cell lines MCF7. The plant extracts play an important role pharmacologically. The whole plant has been used in traditional medicine for decades and the studies done have authenticated the practice. Earlier, as described, the plant has been used in the ayurveda and homeopathy medicine. However, more clinical and pathological studies must be conducted to investigate the unexploited potential of the plant. These studies will be very useful for drug designing in the future.

Keywords: coleus barbatus, HPLC, MPLC, NMR, MCF7, flash chromatograph, ESI-MS, FACS, ELISA.

Procedia PDF Downloads 109

Authors: Gabriela T. Nakashima, Elias R. D. Padilla, Joao L. Barros, Gabriela B. Belini, Hiroyuki Yamamoto, Fabio M. Yamaji

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Biochar can be an alternative to use sugarcane trash. Biochar is a solid material obtained from pyrolysis, that is a biomass thermal degradation with low or no O₂ concentration. Pyrolysis transforms the carbon that is commonly found in other organic structures into a carbon with more stability that can resist microbial decomposition. Biochar has a versatility of uses such as soil fertility, carbon sequestration, energy generation, ecological restoration, and soil remediation. Biochar has a great ability to retain water and nutrients in the soil so that this material can improve the efficiency of irrigation and fertilization. The aim of this study was to characterize biochar produced from sugarcane trash in three different pyrolysis temperatures and determine the lowest temperature with the high yield and carbon content. Physical characterization of this biochar was performed to help the evaluation for the best production conditions. Sugarcane (Saccharum officinarum) trash was collected at Corredeira Farm, located in Ibaté, São Paulo State, Brazil. The farm has 800 hectares of planted area with an average yield of 87 t·ha⁻¹. The sugarcane varieties planted on the farm are: RB 855453, RB 867515, RB 855536, SP 803280, SP 813250. Sugarcane trash was dried and crushed into 50 mm pieces. Crucibles and lids were used to settle the sugarcane trash samples. The higher amount of sugarcane trash was added to the crucible to avoid the O₂ concentration. Biochar production was performed in three different pyrolysis temperatures (200°C, 325°C, 450°C) in 2 hours residence time in the muffle furnace. Gravimetric yield of biochar was obtained. Proximate analysis of biochar was done using ASTM E-872 and ABNT NBR 8112. Volatile matter and ash content were calculated by direct weight loss and fixed carbon content calculated by difference. Porosity measurement was evaluated using an automatic gas adsorption device, Autosorb-1, with CO₂ described by Nakatani. Approximately 0.5 g of biochar in 2 mm particle sizes were used for each measurement. Vacuum outgassing was performed as a pre-treatment in different conditions for each biochar temperature. The pore size distribution of micropores was determined using Horváth-Kawazoe method. Biochar presented different colors for each treatment. Biochar - 200°C presented a higher number of pieces with 10mm or more and did not present the dark black color like other treatments after 2 h residence time in muffle furnace. Also, this treatment had the higher content of volatiles and the lower amount of fixed carbon. In porosity analysis, while the temperature treatments increase, the amount of pores also increase. The increase in temperature resulted in a biochar with a better quality. The pores in biochar can help in the soil aeration, adsorption, water retention. Acknowledgment: This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil – PROAP-CAPES, PDSE and CAPES - Finance Code 001.

Keywords: proximate analysis, pyrolysis, soil amendment, sugarcane straw

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Authors: Joao Almeida, Ana Azevedo, Myriam Kanoun-Boule, Maria Ines Santos, Antonio Tadeu

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The effects of the increasing expansion of cities and climate changes have encouraged European countries and regions to adopt nature-based solutions with ability to mitigate environmental issues and improve life in cities. Among these strategies, green roofs and urban gardens have been considered ingenious solutions, since they have the desirable potential to improve air quality, prevent floods, reduce the heat island effect and restore biodiversity in cities. However, an additional consumption of fresh water and mineral nutrients is necessary to sustain larger green urban areas. This communication discusses the main technical features of a new system to manage urine recovery at the building level and its application in green roofs. The depletion of critical nutrients like phosphorus constitutes an emergency. In turn, their elimination through urine is one of the principal causes for their loss. Thus, urine recovery in buildings may offer numerous advantages, constituting a valuable fertilizer abundantly available in cities and reducing the load on wastewater treatment plants. Although several urine-diverting toilets have been developed for this purpose and some experiments using urine directly in agriculture have already been carried out in Europe, several challenges have emerged with this practice concerning collection, sanitization, storage and application of urine in buildings. To our best knowledge, current buildings are not designed to receive these systems and integrated solutions with ability to self-manage the whole process of urine recovery, including separation, maturation and storage phases, are not known. Additionally, if from a hygiene point of view human urine may be considered a relatively safe fertilizer, the risk of disease transmission needs to be carefully analysed. A reduction in microorganisms can be achieved by storing the urine in closed tanks. However, several factors may affect this process, which may result in a higher survival rate for some pathogens. In this work, urine effluent was collected under real conditions, stored in closed containers and kept in climatic chambers under variable conditions simulating cold, temperate and tropical climates. These samples were subjected to a first physicochemical and microbiological control, which was repeated over time. The results obtained so far suggest that maturation conditions were reached for all the three temperatures and that a storage period of less than three months is required to achieve a strong depletion of microorganisms. The authors are grateful for the Project WashOne (POCI-01-0247-FEDER-017461) funded by the Operational Program for Competitiveness and Internationalization (POCI) of Portugal 2020, with the support of the European Regional Development Fund (FEDER).

Keywords: sustainable green roofs and urban gardens, urban nutrient cycle, urine-based fertilizers, urine recovery in buildings

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Authors: Faris Mohsin Alabeedi

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Pemphigus Vulgaris (PV) is a life-threatening autoimmune blistering disease characterized by the presence of autoantibodies directed against the epidermis's surface proteins. There are two forms of PV, mucocutaneous and mucosal-dominant PV. Disruption of the cell junctions is a hallmark of PV due to the autoantibodies targeting the desmosomal cadherins, desmoglein-3 (Dsg3) and desmoglein-1, leading to acantholysis in the skin and mucous membrane. Although the pathogenesis of PV is known, the detailed molecular events remain not fully understood. Our recent study has shown that both the PV sera and pathogenic anti-Dsg3 antibody AK23 can induce ROS and cause oxidative stress in cultured keratinocytes. In line with our finding, other independent studies also demonstrate oxidative stress in PV. Since Nrf2 plays a crucial role in cellular anti-oxidative stress response, we hypothesize that the expression of Nrf2 may alter in PV. Thus, treatment of cells with PV sera or AK23 may cause changes in Nrf2 expression and distribution. The purpose of this study was to examine the effect of AK23 and PV sera on Nrf2 in a normal human keratinocyte cell line, such as NTERT cells. Both a time-course and dose-dependent experiments with AK23, alongside the matched isotype control IgG, were performed in keratinocyte cultures and analysed by immunofluorescence for Nrf2 and Dsg3. Additionally, the same approach was conducted with the sera from PV patients and healthy individuals that served as a control in this study. All the fluorescent images were analysed using ImageJ software. Each experiment was repeated twice. In general, variations were observed throughout this study. In the dose-response experiments, although enhanced Dsg3 expression was consistently detected in AK23 treated cells, the expression of Nrf2 showed no consistent findings between the experiments, although changes in its expression were noticeable in cells treated with AK23. In the time-course study, a trend with induction of Nrf2 over time was shown in control cells treated with mouse isotype IgG. Treatment with AK23 showed a reduction of Nrf2 in a time-dependent manner, especially at the 24-hour time point. However, the earlier time points, such as 2 hours and 6 hours with AK23 treatments, detected somewhat variations. Finally, PV sera caused a decrease of Dsg3, but on the other hand, variations were observed in Nrf2 expression in PV sera treated cells. In general, PV sera seemed to cause a reduction of Nrf2 in the majority of PV sera treated samples. In addition, more pronounced cytoplasmic expression of Nrf2 has been observed in PV sera treated cells than those treated with AK23, suggesting that polyclonal and monoclonal IgG might induce a different effect on Nrf2 expression and distribution. Further experimental studies are crucial to obtain a more coincide global view of Nrf2-mediated gene regulation. In particular, Pemphigus Voulgaris studies assessing how the Nrf2-dependent network changes from a physiological to a pathological condition can provide insight into disease mechanisms and perhaps initiate further treatment approaches.

Keywords: pemphigus vulgaris, monoclonal antibody against desmoglein-3, Nrf2 oxidative stress, keratinocyte cultures

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Authors: Sachil Kumar, Anoop Kumar Verma, Wahid Ali, Uma Shankar Singh

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Globally approximately 55.3 million people die each year. In the India there were 95 lakh annual deaths in 2013. The number of deaths resulted from homicides, suicides and unintentional injuries in the same period was about 5.7 lakh. The ever-increasing crime rate necessitated the development of methods for determining time since death. An erroneous time of death window can lead investigators down the wrong path or possibly focus a case on an innocent suspect. In this regard a research was carried out by analyzing the temperature dependent degradation of a Cardiac Troponin-T protein (cTnT) in the myocardium postmortem as a marker for time since death. Cardiac tissue samples were collected from (n=6) medico-legal autopsies, (in the Department of Forensic Medicine and Toxicology, King George’s Medical University, Lucknow India) after informed consent from the relatives and studied post-mortem degradation by incubation of the cardiac tissue at room temperature (20±2 OC), 12 0C, 25 0C and 37 0C for different time periods ((~5, 26, 50, 84, 132, 157, 180, 205, and 230 hours). The cases included were the subjects of road traffic accidents (RTA) without any prior history of disease who died in the hospital and their exact time of death was known. The analysis involved extraction of the protein, separation by denaturing gel electrophoresis (SDS-PAGE) and visualization by Western blot using cTnT specific monoclonal antibodies. The area of the bands within a lane was quantified by scanning and digitizing the image using Gel Doc. The data shows a distinct temporal profile corresponding to the degradation of cTnT by proteases found in cardiac muscle. The disappearance of intact cTnT and the appearance of lower molecular weight bands are easily observed. Western blot data clearly showed the intact protein at 42 kDa, two major (27 kDa, 10kDa) fragments, two additional minor fragments (32 kDa) and formation of low molecular weight fragments as time increases. At 12 0C the intensity of band (intact cTnT) decreased steadily as compared to RT, 25 0C and 37 0C. Overall, both PMI and temperature had a statistically significant effect where the greatest amount of protein breakdown was observed within the first 38 h and at the highest temperature, 37 0C. The combination of high temperature (37 0C) and long Postmortem interval (105.15 hrs) had the most drastic effect on the breakdown of cTnT. If the percent intact cTnT is calculated from the total area integrated within a Western blot lane, then the percent intact cTnT shows a pseudo-first order relationship when plotted against the log of the time postmortem. These plots show a good coefficient of correlation of r = 0.95 (p=0.003) for the regression of the human heart at different temperature conditions. The data presented demonstrates that this technique can provide an extended time range during which Postmortem interval can be more accurately estimated.

Keywords: degradation, postmortem interval, proteolysis, temperature, troponin

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Authors: Milica B. Veljković, Milica B. Simović, Marija M. Ćorović, Ana D. Milivojević, Anja I. Petrov, Katarina M. Banjanac, Dejan I. Bezbradica

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In recent decades, the scientific community has recognized the growing importance of prebiotics, and therefore, numerous studies are focused on their economic production due to their low presence in natural resources. It has been confirmed that prebiotics is a source of energy for probiotics in the gastrointestinal tract (GIT) and enable their proliferation, consequently leading to the normal functioning of the intestinal microbiota. Also, products of their fermentation are short-chain fatty acids (SCFA), which play a key role in maintaining and improving the health not only of the GIT but also of the whole organism. Among several confirmed prebiotics, fructooligosaccharides (FOS) are considered interesting candidates for use in a wide range of products in the food industry. They are characterized as low-calorie and non-cariogenic substances that represent an adequate sugar substitute and can be considered suitable for use in products intended for diabetics. The subject of this research will be the production of FOS by transforming sucrose using a fructosyltransferase (FTase) present in commercial preparation Pectinex® Ultra SP-L, with special emphasis on the development of adequate FTase immobilization method that would enable selective isolation of the enzyme responsible for the synthesis of FOS from the complex enzymatic mixture. This would lead to considerable enzyme purification and allow its direct incorporation into different sucrose-based products without the fear that the action of the other hydrolytic enzymes may adversely affect the products' functional characteristics. Accordingly, the possibility of selective immobilization of the enzyme using support with primary amino groups, Purolite® A109, which was previously activated and modified using glutaraldehyde (GA), was investigated. In the initial phase of the research, the effects of individual immobilization parameters such as pH, enzyme concentration, and immobilization time were investigated to optimize the process using support chemically activated with 15% and 0.5% GA to form dimers and monomers, respectively. It was determined that highly active immobilized preparations (371.8 IU/g of support - dimer and 213.8 IU/g of support – monomer) were achieved under acidic conditions (pH 4) provided that an enzyme concentration was 50 mg/g of support after 7 h and 3 h, respectively. Bearing in mind the obtained results of the expressed activity, it is noticeable that the formation of dimers showed higher reactivity compared to the form of monomers. Also, in the case of support modification using 15% GA, the value of the ratio of FTase and pectinase (as dominant enzyme mixture component) activity immobilization yields was 16.45, indicating the high feasibility of selective immobilization of FTase on modified polystyrene resin. After obtaining immobilized preparations of satisfactory features, they were tested in a reaction of FOS synthesis under determined optimal conditions. The maximum FOS yields of approximately 50% of total carbohydrates in the reaction mixture were recorded after 21 h. Finally, it can be concluded that the examined immobilization method yielded highly active, stable and, more importantly, refined enzyme preparation that can be further utilized on a larger scale for the development of continual processes for FOS synthesis, as well as for modification of different sucrose-based mediums.

Keywords: chemical modification, fructooligosaccharides, glutaraldehyde, immobilization of fructosyltransferase

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Authors: Melanie Francois, Gilles Caboche, Frederic Demoisson, Francois Maeght, Maria Paola Carpanese, Lionel Combemale, Pascal Briois

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Finding new clean, and efficient way for energy production is one of the actual global challenges. Advances in fuel cell technology have shown that, for few years, Protonic Ceramic Fuel Cell (PCFC) has attracted much attention in the field of new hydrogen energy thanks to their lower working temperature, possible higher efficiency, and better durability than classical SOFC. On the contrary of SOFC, where O²⁻ oxygen ion is the charge carrier, PCFC works with H⁺ proton as a charge carrier. Consequently, the lower activation energy of proton diffusion compared to the one of oxygen ion explains those benefits and allows PCFC to work in the 400-600°C temperature range. Doped-BaCeO₃ is currently the most chosen material for this application because of its high protonic conductivity; for example, BaCe₀.₉Y₀.₁O₃ δ exhibits a total conductivity of 1.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, BaCeO₃ based perovskite has low stability in H₂O and/or CO₂ containing atmosphere, which limits their practical application. On the contrary, BaZrO₃ based perovskite exhibits good chemical stability but lower total conductivity than BaCeO₃ due to its larger grain boundary resistance. By substituting zirconium with 20% of yttrium, it is possible to achieve a total conductivity of 2.5×10⁻² S.cm⁻¹ at 600°C in wet H₂. However, the high refractory property of BaZr₀.₈Y₀.₂O₃-δ (noted BZY20) causes problems to obtain a dense membrane with large grains. Thereby, using a synthesis process that gives fine particles could allow better sinterability and thus decrease the number of grain boundaries leading to a higher total conductivity. In this work, BaZr₀.₈Y₀.₂O₃-δ have been synthesized by classical batch hydrothermal device and by a continuous hydrothermal device developed at ICB laboratory. The two variants of this process are able to work in supercritical conditions, leading to the formation of nanoparticles, which could be sintered at a lower temperature. The as-synthesized powder exhibits the right composition for the perovskite phase, impurities such as BaCO₃ and YO-OH were detected at very low concentration. Microstructural investigation and densification rate measurement showed that the addition of 1 wt% of ZnO as sintering aid and a sintering at 1550°C for 5 hours give high densified electrolyte material. Furthermore, it is necessary to heat the synthesized powder prior to the sintering to prevent the formation of secondary phases. It is assumed that this thermal treatment homogenizes the crystal structure of the powder and reduces the number of defects into the bulk grains. Electrochemical impedance spectroscopy investigations in various atmospheres and a large range of temperature (200-700°C) were then performed on sintered samples, and the protonic conductivity of BZY20 has been highlighted. Further experiments on half-cell, NiO-BZY20 as anode and BZY20 as electrolyte, are in progress.

Keywords: hydrothermal synthesis, impedance measurement, Y-doped BaZrO₃, proton conductor

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Authors: Kimberly Samaha

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In order to attract new types of investors into the emerging Bio-Economy, a new set of metrics and measurement system is needed to better quantify the environmental, social and economic impacts of circular zero-waste design. The Bio-Hub Ecosystem model was developed to address a critical area of concern within the global energy market regarding the use of biomass as a feedstock for power plants. Lack of an economically-viable business model for bioenergy facilities has resulted in the continuation of idled and decommissioned plants. In particular, the forestry-based plants which have been an invaluable outlet for woody biomass surplus, forest health improvement, timber production enhancement, and especially reduction of wildfire risk. This study looked at repurposing existing biomass-energy plants into Circular Zero-Waste Bio-Hub Ecosystems. A Bio-Hub model that first targets a ‘whole-tree’ approach and then looks at the circular economics of co-hosting diverse industries (wood processing, aquaculture, agriculture) in the vicinity of the Biomass Power Plants facilities. It proposes not only models for integration of forestry, aquaculture, and agriculture in cradle-to-cradle linkages of what have typically been linear systems, but the proposal also allows for the early measurement of the circularity and impact of resource use and investment risk mitigation, for these systems. Typically, life cycle analyses measure environmental impacts of different industrial production stages and are not integrated with indicators of material use circularity. This concept paper proposes the further development of a new set of metrics that would illustrate not only the typical life-cycle analysis (LCA), which shows the reduction in greenhouse gas (GHG) emissions, but also the zero-waste circularity measures of mass balance of the full value chain of the raw material and energy content/caloric value. These new measures quantify key impacts in making hyper-efficient use of natural resources and eliminating waste to landfills. The project utilized traditional LCA using the GREET model where the standalone biomass energy plant case was contrasted with the integration of a jet-fuel biorefinery. The methodology was then expanded to include combinations of co-hosts that optimize the life cycle of woody biomass from tree to energy, CO₂, heat and wood ash both from an energy/caloric value and for mass balance to include reuse of waste streams which are typically landfilled. The major findings of both a formal LCA study resulted in the masterplan for the first Bio-Hub to be built in West Enfield, Maine. Bioenergy facilities are currently at a critical juncture where they have an opportunity to be repurposed into efficient, profitable and socially responsible investments, or be idled and scrapped. If proven as a model, the expedited roll-out of these innovative scenarios can set a new standard for circular zero-waste projects that advance the critical transition from the current ‘take-make-dispose’ paradigm inherent in the energy, forestry and food industries to a more sustainable bio-economy paradigm where waste streams become valuable inputs, supporting local and rural communities in simple, sustainable ways.

Keywords: bio-economy, biomass energy, financing, metrics

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Authors: Tanveer Ahmed Choudhury

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Background: Bangladesh is one of the largest deltas in the world, with high population density and high rates of poverty and illiteracy. 80% of the country is on low-lying floodplains, leaving the country one of the most vulnerable to the adverse effects of climate change: sea level rise, cyclones and storms, salinity intrusion, rising temperatures and heavy monsoon downpours. Such climatic events already limit Economic Development in the country. Although Bangladesh has had little responsibility in contributing to global climatic change, it is vulnerable to both its direct and indirect impacts. Real threats include reduced agricultural production, worsening food security, increased incidence of flooding and drought, spreading disease and an increased risk of conflict over scarce land and water resources. Currently, 8.3 million Bangladeshis live in cyclone high risk areas. However, by 2050 this is expected to grow to 20.3 million people, if proper adaptive actions are not taken. Under a high emissions scenario, an additional 7.6 million people will be exposed to very high salinity by 2050 compared to current levels. It is also projected that, an average of 7.2 million people will be affected by flooding due to sea level rise every year between 2070-2100 and If global emissions decrease rapidly and adaptation interventions are taken, the population affected by flooding could be limited to only about 14,000 people. To combat the climate change adverse effects, Bangladesh government has initiated many adaptive measures specially in infrastructure and renewable energy sector. Government is investing huge money and initiated many projects which have been proved very success full. Objectives: The objective of this paper is to describe some successful measures initiated by Bangladesh government in its effort to make the country a Climate Resilient. Methodology: Review of operation plan and activities of different relevant Ministries of Bangladesh government. Result: The following initiative projects, programs and activities are considered as best practices for Climate Change adaptation successes for Bangladesh: 1. The Infrastructure Development Company Limited (IDCOL); 2. Climate Change and Health Promotion Unit (CCHPU); 3. The Climate Change Trust Fund (CCTF); 4. Community Climate Change Project (CCCP); 5. Health, Population, Nutrition Sector Development Program (HPNSDP, 2011-2016)- "Climate Change and Environmental Issues"; 6. Ministry of Health and Family Welfare, Bangladesh and WHO Collaboration; - National Adaptation Plan. -"Building adaptation to climate change in health in least developed countries through resilient WASH". 7. COP-21 “Climate and health country profile -2015 Bangladesh. Conclusion: Due to a vast coastline, low-lying land and abundance of rivers, Bangladesh is highly vulnerable to climate change. Having extensive experience with facing natural disasters, Bangladesh has developed a successful adaptation program, which led to a significant reduction in casualties from extreme weather events. In a low income country setting, Bangladesh had successfully adapted various projects and initiatives to combat future Climate Change challenges.

Keywords: climate, change, success, Bangladesh

Procedia PDF Downloads 244

Authors: Pedro B. Antunes, Paulo J. Ramísio

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Road runoff is a linear source of diffuse pollution that can cause significant environmental impacts. During rainfall events, pollutants from both stationary and mobile sources, which have accumulated on the road surface, are dragged through the superficial runoff. Road runoff in coastal zones may present high levels of salinity and chlorides due to the proximity of the sea and transported marine aerosols. Appearing to be correlated to this process, organic matter concentration may also be significant. This study assesses this phenomenon with the purpose of identifying the relationships between monitored water quality parameters and intrinsic site variables. To achieve this objective, an extensive monitoring program was conducted on a Portuguese coastal highway. The study included thirty rainfall events, in different weather, traffic and salt deposition conditions in a three years period. The evaluations of various water quality parameters were carried out in over 200 samples. In addition, the meteorological, hydrological and traffic parameters were continuously measured. The salt deposition rates (SDR) were determined by means of a wet candle device, which is an innovative feature of the monitoring program. The SDR, variable throughout the year, appears to show a high correlation with wind speed and direction, but mostly with wave propagation, so that it is lower in the summer, in spite of the favorable wind direction in the case study. The distance to the sea, topography, ground obstacles and the platform altitude seems to be also relevant. It was confirmed the high salinity in the runoff, increasing the concentration of the water quality parameters analyzed, with significant amounts of seawater features. In order to estimate the correlations and patterns of different water quality parameters and variables related to weather, road section and salt deposition, the study included exploratory data analysis using different techniques (e.g. Pearson correlation coefficients, Cluster Analysis and Principal Component Analysis), confirming some specific features of the investigated road runoff. Significant correlations among pollutants were observed. Organic matter was highlighted as very dependent of salinity. Indeed, data analysis showed that some important water quality parameters could be divided into two major clusters based on their correlations to salinity (including organic matter associated parameters) and total suspended solids (including some heavy metals). Furthermore, the concentrations of the most relevant pollutants seemed to be very dependent on some meteorological variables, particularly the duration of the antecedent dry period prior to each rainfall event and the average wind speed. Based on the results of a monitoring case study, in a coastal zone, it was proven that SDR, associated with the hydrological characteristics of road runoff, can contribute for a better knowledge of the runoff characteristics, and help to estimate the specific nature of the runoff and related water quality parameters.

Keywords: coastal zones, monitoring, road runoff pollution, salt deposition

Procedia PDF Downloads 235

Authors: Kaushalendra Kumar, Abhishek Kumar, Chandra Moni, Sanjay Kumar, P. K. Singh, Ajeet Kumar

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Present study investigated the dietary inclusion of Moringa oleifera leaf meal (MOLM) on production efficiency, hemato-biochemical profile and economy of Vanaraja birds under tropical condition. Experiment was conducted for a period of 56 days on 300 Vanaraja birds randomly divided in to five different experimental groups including control of 60 birds each group replicated with 20 chicks in each replicate. T1, T2, T3, T4, and T5 were offered with 0, 5, 10, 15, and 20% Moringa oleifera leaf meal along with basal ration. All the standard managemental practices were followed during experimental period including vaccination schedule. Locally available Moringa oleifera leaves were harvested at mature stage and allowed to dry under shady and aerated conditions. Thereafter, dried leaves were milled to make a leaf meal and stored in the airtight nylon bags to avoid any possible contamination from foreign material and use for experiment. Production parameters were calculated based on the amount of feed consumed and weight gain every weeks. The body weight gain of T2 group was significantly (P < 0.05) higher side whereas T3 group was comparable with control. The feed conversion ratio for T2 group was found to be significantly (P < 0.05) lower than all other treatment groups, while none of the group was comparable with each other. At the end of the experiment blood samples were collected from birds for haematology study while serum biochemistry performed using spectrophotometer following statndard protocols. The haematological attributes were significantly (P > 0.05) not differed among the groups. However, serum biochemistry showed significant reduction (P < 0.05) of blood urea nitrogen, uric acid and creatinine level with higher level of MOLM diet, indicates better utilization of protein supplemented through MOLM. The total cholesterol and triglyceride level was declined significantly (P < 0.05) as compare to control group with increased level of MOLM in basal diet, decreasing trend of serum cholesterol noted. However, value of HDL for T3 group was highest and for T1 group was lowest but no significant difference (P < 0.05) found among the groups. It might be due to presence of β-sitosterol a bioactive compound present in MOLM which causes lowering of plasma concentration of LDL. During experiment total, LDL and VLDL level was found to be decreased significantly (P < 0.05) as compare to control group. It was observed that the production efficiency of birds significantly improved with 5% followed by 10% Moringa oleifera leaf meal among the treatment groups. However, the maximum profit per kg live weight was noted in 10 % level and least profit observed in 20% MOLM fed group. It was concluded that the dietary inclusion of MOLM improved overall performances without affecting metabolic status and effective in reducing cholesterol level reflects healthy chicken production for human consumption.

Keywords: hemato biochemistry, Moringa oleifera leaf meal, performance, Vanaraja birds

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Authors: Supriya Majumder, Pabitra Banik

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Fates of Arsenic (As) on the soil-plant environment belong to the critical emerging issue, which in turn to appraises the threatening implications of a human health risk — assessing the dynamics of As in soil solid components are likely to impose its potential availability towards plant uptake. In the present context, we introduced an improved Sequential Extraction Procedure (SEP) questioning to identify solid-phase speciation of As in paddy soil under variable soil environmental conditions during two consecutive seasons of rice cultivation practices. We coupled gradients of water management practices with the addition of fertilizer amendments to assess the changes in a partition of As through a field experimental study during monsoon and post-monsoon season using two rice cultivars. Water management regimes were varied based on the methods of cultivation of rice by Conventional (waterlogged) vis-a-vis System of Rice Intensification-SRI (saturated). Fertilizer amendment through the nutrient treatment of absolute control, NPK-RD, NPK-RD + Calcium silicate, NPK-RD + Ferrous sulfate, Farmyard manure (FYM), FYM + Calcium silicate, FYM + Ferrous sulfate, Vermicompost (VC), VC + Calcium silicate, VC + Ferrous sulfate were selected to construct the study. After harvest, soil samples were sequentially extracted to estimate partition of As among the different fractions such as: exchangeable (F1), specifically sorbed (F2), As bound to amorphous Fe oxides (F3), crystalline Fe oxides (F4), organic matter (F5) and residual phase (F6). Results showed that the major proportions of As were found in F3, F4 and F6, whereas F1 exhibited the lowest proportion of total soil As. Among the nutrient treatment mediated changes on As fractions, the application of organic manure and ferrous sulfate were significantly found to restrict the release of As from exchangeable phase. Meanwhile, conventional practice produced much higher release of As from F1 as compared to SRI, which may substantially increase the environmental risk. In contrast, SRI practice was found to retain a significantly higher proportion of As in F2, F3, and F4 phase resulting restricted mobilization of As. This was critically reflected towards rice grain As bioavailability where the reduction in grain As concentration of 33% and 55% in SRI concerning conventional treatment (p <0.05) during monsoon and post-monsoon season respectively. Also, prediction assay for rice grain As bioavailability based on the linear regression model was performed. Results demonstrated that rice grain As concentration was positively correlated with As concentration in F1 and negatively correlated with F2, F3, and F4 with a satisfactory level of variation being explained (p <0.001). Finally, we conclude that F1, F2, F3 and F4 are the major soil. As fractions critically may govern the potential availability of As in soil and suggest that rice cultivation with the SRI treatment is particularly at less risk of As availability in soil. Such exhaustive information may be useful for adopting certain management practices for rice grown in contaminated soil concerning to the environmental issues in particular.

Keywords: arsenic, fractionation, paddy soil, potential availability

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Authors: Serdar Delice, Mehmet Isik, Nizami Hasanli, Kadir Goksen

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Researchers have donated great interest to ternary and quaternary semiconductor compounds especially with the improvement of the optoelectronic technology. The quaternary compound Tl2Ga2Se3S which was grown by Bridgman method carries the properties of ternary thallium chalcogenides group of semiconductors with layered structure. This compound can be formed from TlGaSe2 crystals replacing the one quarter of selenium atom by sulfur atom. Although Tl2Ga2Se3S crystals are not intentionally doped, some unintended defect types such as point defects, dislocations and stacking faults can occur during growth processes of crystals. These defects can cause undesirable problems in semiconductor materials especially produced for optoelectronic technology. Defects of various types in the semiconductor devices like LEDs and field effect transistor may act as a non-radiative or scattering center in electron transport. Also, quick recombination of holes with electrons without any energy transfer between charge carriers can occur due to the existence of defects. Therefore, the characterization of defects may help the researchers working in this field to produce high quality devices. Thermoluminescence (TL) is an effective experimental method to determine the kinetic parameters of trap centers due to defects in crystals. In this method, the sample is illuminated at low temperature by a light whose energy is bigger than the band gap of studied sample. Thus, charge carriers in the valence band are excited to delocalized band. Then, the charge carriers excited into conduction band are trapped. The trapped charge carriers are released by heating the sample gradually and these carriers then recombine with the opposite carriers at the recombination center. By this way, some luminescence is emitted from the samples. The emitted luminescence is converted to pulses by using an experimental setup controlled by computer program and TL spectrum is obtained. Defect characterization of Tl2Ga2Se3S single crystals has been performed by TL measurements at low temperatures between 10 and 300 K with various heating rate ranging from 0.6 to 1.0 K/s. The TL signal due to the luminescence from trap centers revealed one glow peak having maximum temperature of 36 K. Curve fitting and various heating rate methods were used for the analysis of the glow curve. The activation energy of 13 meV was found by the application of curve fitting method. This practical method established also that the trap center exhibits the characteristics of mixed (general) kinetic order. In addition, various heating rate analysis gave a compatible result (13 meV) with curve fitting as the temperature lag effect was taken into consideration. Since the studied crystals were not intentionally doped, these centers are thought to originate from stacking faults, which are quite possible in Tl2Ga2Se3S due to the weakness of the van der Waals forces between the layers. Distribution of traps was also investigated using an experimental method. A quasi-continuous distribution was attributed to the determined trap centers.

Keywords: chalcogenides, defects, thermoluminescence, trap centers

Procedia PDF Downloads 276

Authors: Margarida Soares, Zlatina Genisheva, Lucas Nascimento, André Ribeiro, Tiago Miranda, Eduardo Pereira, Joana Carvalho

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In the current global context, we face a significant challenge: the rapid population increase combined with the pressing need for sustainable management of agro-industrial waste. Beyond understanding how population growth impacts waste generation, it is essential to first identify the primary types of waste produced and the countries responsible to guide targeted actions. This study presents key statistical data on waste production from the agriculture, forestry, and fishing sectors across the European Union, alongside information on the agricultural areas dedicated to crop production in each European Union country. These insights will form the basis for future research into waste production by crop type and country to improve waste management practices and promote recovery methods that are vital for environmental sustainability. The agricultural sector must stay at the forefront of scientific and technological advancements to meet climate change challenges, protect the environment, and ensure food and health security. The study's findings indicate that population growth significantly increases pressure on natural resources, leading to a rise in agro-industrial waste production. EUROSTAT data shows that, in 2020, the agriculture, forestry, and fishing sectors produced over 21 million tons of waste. Spain emerged as the largest producer, contributing nearly 30% of the EU's total waste in these sectors. Furthermore, five countries—Spain, the Netherlands, France, Sweden, and Germany—were responsible for producing more than two-thirds of the waste from these sectors. Regarding agricultural land use, the data for 2020 revealed that around two-thirds of the total agricultural area was concentrated in six countries: France, Spain, Germany, Poland, Romania, and Italy. Regarding waste production per capita, the Netherlands had the highest figures in the EU for 2020. The data presented in this study highlights the urgent need for action in managing agricultural waste in the EU. As population growth continues to drive up demand for agricultural products, waste generation will inevitably rise unless significant changes are made in managing of agro-industrial waste. The countries must lead the way in adopting technological waste management strategies that focus on reducing, reusing, and recycling waste to benefit both the environment and society. Equally important is the need to promote collaborative efforts between governments, industries, and research institutions to develop and implement technologies that transform waste into valuable resources. The insights from this study are critical for informing future strategies to improve the management and valorization of waste from the agro-industrial sector. One of the most promising approaches is adopting circular economy principles to create closed-loop systems that minimize environmental impacts. By rethinking waste as a valuable resource rather than a by-product, agricultural industries can contribute to more sustainable practices that support both environmental health and economic growth.

Keywords: agricultural area, agricultural waste, circular economy, environmental challenges, population growth

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Authors: Felix Darko-Amoah, Daniel Acquah

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In contemporary ecosystems for developing countries like Ghana, the need to explore innovative solutions for sustainable livelihoods of farmers is more important than ever. With Ghana’s population growing steadily and the demand for food, fiber and shelter increasing, it is imperative that the construction industry and agriculture come together to address the challenges faced by farmers in the country. In order to enhance the livelihoods of cocoa farmers in Ghana, this paper provides an innovative strategy that aims to integrate the areas of civil engineering and cash crop agriculture. This study focuses on cocoa cultivation in poorer nations, where farmers confront a variety of difficulties include restricted access to financing, subpar infrastructure, and insufficient support services. We seek to improve farmers' access to financing, improve infrastructure, and provide support services that are essential to their success by combining the fields of building engineering and cocoa production. The findings of the study are beneficial to cocoa producers, community extension agents, and construction engineers. In order to accomplish our objectives, we conducted 307 of field investigations in particular cocoa growing communities in the Western Region of Ghana. Several studies have shown that there is a lack of adequate infrastructure and financing, leading to low yields, subpar beans, and low farmer profitability in developing nations like Ghana. Our goal is to give farmers access to better infrastructure, better financing, and support services that are crucial to their success through the fusion of construction engineering and cocoa production. Based on data gathered from the field investigations, the results show that the employment of appropriate technology and methods for developing structures, roads, and other infrastructure in rural regions is one of the essential components of this strategy. For instance, we find that using affordable, environmentally friendly materials like bamboo, rammed earth, and mud bricks can assist to cut expenditures while also protecting the environment. By applying simple relational techniques to the data gathered, the results also show that construction engineers are crucial in planning and building infrastructure that is appropriate for the local environment and circumstances and resilient to natural disasters like floods. Thus, the convergence of construction engineering and cash crop cultivation is another crucial component of the agriculture-construction interplay. For instance, farmers can receive financial assistance to buy essential inputs, such as seeds, fertilizer, and tools, as well as training in proper farming methods. Moreover, extension services can be offered to assist farmers in marketing their crops and enhancing their livelihoods and revenue. In conclusion, our analysis of responses from the 307 participants depicts that the combination of construction engineering and cash crop agriculture offers an innovative approach to improving farmers' livelihoods in cocoa farming communities in Ghana. In conclusion, by inculcating the findings of this study into core decision-making, policymakers can help farmers build sustainable and profitable livelihoods by addressing challenges such as limited access to financing, poor infrastructure, and inadequate support services.

Keywords: cocoa agriculture, construction engineering, farm buildings and equipment, improved livelihoods of farmers

Procedia PDF Downloads 88

Authors: D. P. Houhoula, J. Papaparaskevas, S. Konteles, A. Dargenta, A. Farka, C. Spyrou, M. Ziaka, S. Koussisis, E. Charvalos

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Objectives: Nanotechnology is providing revolutionary opportunities for the rapid and simple diagnosis of many infectious diseases. Staphylococcus aureus, Listeria monocytogenes and Salmonella enteritis are important human pathogens. Diagnostic assays for bacterial culture and identification are time consuming and laborious. There is an urgent need to develop rapid, sensitive, and inexpensive diagnostic tests. In this study, a gold nanoprobe strategy developed and relies on the colorimetric differentiation of specific DNA sequences based approach on differential aggregation profiles in the presence or absence of specific target hybridization. Method: Gold nanoparticles (AuNPs) were purchased from Nanopartz. They were conjugated with thiolated oligonucleotides specific for the femA gene for the identification of members of Staphylococcus aureus, the mecA gene for the differentiation of Staphylococcus aureus and MRSA Staphylococcus aureus, hly gene encoding the pore-forming cytolysin listeriolysin for the identification of Listeria monocytogenes and the invA sequence for the identification of Salmonella enteritis. DNA isolation from Staphylococcus aureus Listeria monocytogenes and Salmonella enteritis cultures was performed using the commercial kit Nucleospin Tissue (Macherey Nagel). Specifically 20μl of DNA was diluted in 10mMPBS (pH5). After the denaturation of 10min, 20μl of AuNPs was added followed by the annealing step at 58oC. The presence of a complementary target prevents aggregation with the addition of acid and the solution remains pink, whereas in the opposite event it turns to purple. The color could be detected visually and it was confirmed with an absorption spectrum. Results: Specifically, 0.123 μg/μl DNA of St. aureus, L.monocytogenes and Salmonella enteritis was serially diluted from 1:10 to 1:100. Blanks containing PBS buffer instead of DNA were used. The application of the proposed method on isolated bacteria produced positive results with all the species of St. aureus and L. monocytogenes and Salmonella enteritis using the femA, mecA, hly and invA genes respectively. The minimum detection limit of the assay was defined at 0.2 ng/μL of DNA. Below of 0.2 ng/μL of bacterial DNA the solution turned purple after addition of HCl, defining the minimum detection limit of the assay. None of the blank samples was positive. The specificity was 100%. The application of the proposed method produced exactly the same results every time (n = 4) the evaluation was repeated (100% repeatability) using the femA, hly and invA genes. Using the gene mecA for the differentiation of Staphylococcus aureus and MRSA Staphylococcus aureus the method had a repeatability 50%. Conclusion: The proposed method could be used as a highly specific and sensitive screening tool for the detection and differentiation of Staphylococcus aureus Listeria monocytogenes and Salmonella enteritis. The use AuNPs for the colorimetric detection of DNA targets represents an inexpensive and easy-to-perform alternative to common molecular assays. The technology described here, may develop into a platform that could accommodate detection of many bacterial species.

Keywords: gold nanoparticles, pathogens, nanotechnology, bacteria

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Authors: Ishita Singh

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Social-dimension of Climate Change is no longer peripheral to Science, Technology and Innovation (STI). Indeed, STI is being mobilized to address small farmers’ vulnerability and adaptation to Climate Change. The experiences from the cold desert of Leh (Ladakh) in North-West Himalaya illustrate the potential of STI to address the challenges of Climate Change and the needs of small farmers through the use of Artificial Glacier Techniques. Small farmers have a unique technique of water harvesting to augment irrigation, called “Artificial Glaciers” - an intricate network of water channels and dams along the upper slope of a valley that are located closer to villages and at lower altitudes than natural glaciers. It starts to melt much earlier and supplements additional irrigation to small farmers’ improving their livelihoods. Therefore, the issue of vulnerability, adaptive capacity and adaptation strategy needs to be analyzed in a local context and the communities as well as regions where people live. Leh (Ladakh) in North-West Himalaya provides a Case Study for exploring the ways in which adaptation to Climate Change is taking place at a community scale using Artificial Glacier Technology. With the above backdrop, an attempt has been made to analyze the rural poor households' vulnerability and adaptation practices to Climate Change using this technology, thereby drawing lessons on vulnerability-livelihood interactions in the cold desert of Leh (Ladakh) in North-West Himalaya, India. The study is based on primary data and information collected from 675 households confined to 27 villages of Leh (Ladakh) in North-West Himalaya, India. It reveals that 61.18% of the population is driving livelihoods from agriculture and allied activities. With increased irrigation potential due to the use of Artificial Glaciers, food security has been assured to 77.56% of households and health vulnerability has been reduced in 31% of households. Seasonal migration as a livelihood diversification mechanism has declined in nearly two-thirds of households, thereby improving livelihood strategies. Use of tactical adaptations by small farmers in response to persistent droughts, such as selling livestock, expanding agriculture lands, and use of relief cash and foods, have declined to 20.44%, 24.74% and 63% of households. However, these measures are unsustainable on a long-term basis. The role of policymakers and societal stakeholders becomes important in this context. To address livelihood challenges, the role of technology is critical in a multidisciplinary approach involving multilateral collaboration among different stakeholders. The presence of social entrepreneurs and new actors on the adaptation scene is necessary to bring forth adaptation measures. Better linkage between Science and Technology policies, together with other policies, should be encouraged. Better health care, access to safe drinking water, better sanitary conditions, and improved standards of education and infrastructure are effective measures to enhance a community’s adaptive capacity. However, social transfers for supporting climate adaptive capacity require significant amounts of additional investment. Developing institutional mechanisms for specific adaptation interventions can be one of the most effective ways of implementing a plan to enhance adaptation and build resilience.

Keywords: climate change, adaptation, livelihood, stakeholders

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Authors: A. Volperts, G. Dobele, A. Zhurinsh, I. Kruusenberg, A. Plavniece, J. Locs

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Nowadays energy consumption constantly increases and development of effective and cheap electrochemical sources of power, such as fuel cells and electrochemical capacitors, is topical. Due to their high specific power, charge and discharge rates, working lifetime supercapacitor based energy accumulation systems are more and more extensively being used in mobile and stationary devices. Lignocellulosic materials are widely used as precursors and account for around 45% of the total raw materials used for the manufacture of activated carbon which is the most suitable material for supercapacitors. First part of our research is devoted to study of influence of main stages of wood thermochemical activation parameters on activated carbons porous structure formation. It was found that the main factors governing the properties of carbon materials are specific surface area, volume and pore size distribution, particles dispersity, ash content and oxygen containing groups content. Influence of activated carbons attributes on capacitance and working properties of supercapacitor are demonstrated. The correlation between activated carbons porous structure indices and electrochemical specifications of supercapacitors with electrodes made from these materials has been determined. It is shown that if synthesized activated carbons are used in supercapacitors then high specific capacitances can be reached – more than 380 F/g in 4.9M sulfuric acid based electrolytes and more than 170 F/g in 1 M tetraethylammonium tetrafluoroborate in acetonitrile electrolyte. Power specifications and minimal price of H₂-O₂ fuel cells are limited by the expensive platinum-based catalysts. The main direction in development of non-platinum catalysts for the oxygen reduction is the study of cheap porous carbonaceous materials which can be obtained by the pyrolysis of polymers including renewable biomass. It is known that nitrogen atoms in carbon materials to a high degree determine properties of the doped activated carbons, such as high electrochemical stability, hardness, electric resistance, etc. The lack of sufficient knowledge on the doping of the carbon materials calls for the ongoing researches of properties and structure of modified carbon matrix. In the second part of this study, highly porous activated carbons were synthesized using alkali thermochemical activation from wood, cellulose and cellulose production residues – craft lignin and sewage sludge. Activated carbon samples were doped with dicyandiamide and melamine for the application as fuel cell cathodes. Conditions of nitrogen introduction (solvent, treatment temperature) and its content in the carbonaceous material, as well as porous structure characteristics, such as specific surface and pore size distribution, were studied. It was found that efficiency of doping reaction depends on the elemental oxygen content in the activated carbon. Relationships between nitrogen content, porous structure characteristics and electrodes electrochemical properties are demonstrated.

Keywords: activated carbons, low-temperature fuel cells, nitrogen doping, porous structure, supercapacitors

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Authors: Aleksandra Jonas, Aleksandra Gronowska, Maciej Ścigacz, Szymon Jadczak

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Exact Data is a smart tool which helps with meaningful marketing content creation. It helps marketers achieve this by analyzing the text of an advertisement before and after its publication on social media sites like Facebook or Instagram. In our research we focus on four areas of natural language processing (NLP): grammar correction, sentiment analysis, irony detection and advertisement interpretation. Our research has identified a considerable lack of NLP tools for the Polish language, which specifically aid online marketers. In light of this, our research team has set out to create a robust and versatile NLP tool for the Polish language. The primary objective of our research is to develop a tool that can perform a range of language processing tasks in this language, such as sentiment analysis, text classification, text correction and text interpretation. Our team has been working diligently to create a tool that is accurate, reliable, and adaptable to the specific linguistic features of Polish, and that can provide valuable insights for a wide range of marketers needs. In addition to the Polish language version, we are also developing an English version of the tool, which will enable us to expand the reach and impact of our research to a wider audience. Another area of focus in our research involves tackling the challenge of the limited availability of linguistically diverse corpora for non-English languages, which presents a significant barrier in the development of NLP applications. One approach we have been pursuing is the translation of existing English corpora, which would enable us to use the wealth of linguistic resources available in English for other languages. Furthermore, we are looking into other methods, such as gathering language samples from social media platforms. By analyzing the language used in social media posts, we can collect a wide range of data that reflects the unique linguistic characteristics of specific regions and communities, which can then be used to enhance the accuracy and performance of NLP algorithms for non-English languages. In doing so, we hope to broaden the scope and capabilities of NLP applications. Our research focuses on several key NLP techniques including sentiment analysis, text classification, text interpretation and text correction. To ensure that we can achieve the best possible performance for these techniques, we are evaluating and comparing different approaches and strategies for implementing them. We are exploring a range of different methods, including transformers and convolutional neural networks (CNNs), to determine which ones are most effective for different types of NLP tasks. By analyzing the strengths and weaknesses of each approach, we can identify the most effective techniques for specific use cases, and further enhance the performance of our tool. Our research aims to create a tool, which can provide a comprehensive analysis of advertising effectiveness, allowing marketers to identify areas for improvement and optimize their advertising strategies. The results of this study suggest that a smart tool for advertisement analysis can provide valuable insights for businesses seeking to create effective advertising campaigns.

Keywords: NLP, AI, IT, language, marketing, analysis

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Authors: Ousmane Sarr

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The Senegalese coasts have high productivity of fishery resources due to the frequency of intense up-welling system that occurs along its coast, caused by the maritime trade winds making its waters nutrients rich. Fishing plays a primordial role in Senegal's socioeconomic plans and food security. However, a global diagnosis of the Senegalese maritime fishing sector has highlighted the challenges this sector encounters. Among these concerns, some significant stocks, a priority target for artisanal fishing, need further assessment. If no efforts are made in this direction, most stock will be overexploited or even in decline. It is in this context that this research was initiated. This investigation aimed to apply a multi-modal approach (LBB, Catch-only-based CMSY model and its most recent version (CMSY++); JABBA, and JABBA-Select) to assess the stock of Atlantic bonito, Sarda sarda (Bloch, 1793) in the Senegalese Exclusive Economic Zone (SEEZ). Available catch, effort, and size data from Atlantic bonito over 15 years (2004-2018) were used to calculate the nominal and standardized CPUE, size-frequency distribution, and length at retentions (50 % and 95 % selectivity) of the species. These relevant results were employed as input parameters for stock assessment models mentioned above to define the stock status of this species in this region of the Atlantic Ocean. The LBB model indicated an Atlantic bonito healthy stock status with B/BMSY values ranging from 1.3 to 1.6 and B/B0 values varying from 0.47 to 0.61 of the main scenarios performed (BON_AFG_CL, BON_GN_Length, and BON_PS_Length). The results estimated by LBB are consistent with those obtained by CMSY. The CMSY model results demonstrate that the SEEZ Atlantic bonito stock is in a sound condition in the final year of the main scenarios analyzed (BON, BON-bt, BON-GN-bt, and BON-PS-bt) with sustainable relative stock biomass (B2018/BMSY = 1.13 to 1.3) and fishing pressure levels (F2018/FMSY= 0.52 to 1.43). The B/BMSY and F/FMSY results for the JABBA model ranged between 2.01 to 2.14 and 0.47 to 0.33, respectively. In contrast, The estimated B/BMSY and F/FMSY for JABBA-Select ranged from 1.91 to 1.92 and 0.52 to 0.54. The Kobe plots results of the base case scenarios ranged from 75% to 89% probability in the green area, indicating sustainable fishing pressure and an Atlantic bonito healthy stock size capable of producing high yields close to the MSY. Based on the stock assessment results, this study highlighted scientific advice for temporary management measures. This study suggests an improvement of the selectivity parameters of longlines and purse seines and a temporary prohibition of the use of sleeping nets in the fishery for the Atlantic bonito stock in the SEEZ based on the results of the length-base models. Although these actions are temporary, they can be essential to reduce or avoid intense pressure on the Atlantic bonito stock in the SEEZ. However, it is necessary to establish harvest control rules to provide coherent and solid scientific information that leads to appropriate decision-making for rational and sustainable exploitation of Atlantic bonito in the SEEZ and the Eastern Atlantic Ocean.

Keywords: multi-model approach, stock assessment, atlantic bonito, SEEZ

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Authors: E. Poupelloz, S. Gauffinet

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Ettringite Ca₆Al₂(SO₄)₃(OH)₁₂26H₂O is one of the major hydrates formed during cement hydration. Ettringite forms in Portland cement from the reaction between tricalcium aluminate Ca₃Al₂O₆ and calcium sulfate. Ettringite is also present in calcium sulfoaluminate cement in which it is the major hydrate, formed by the reaction between yeelimite Ca₄(AlO₂)₆SO₄ and calcium sulfate. About the formation of ettringite, numerous results are available in the literature even if some issues are still under discussion. However, almost all published work about ettringite was done on cementitious systems. Yet in cement, hydration reactions are very complex, the result of dissolution-precipitation processes and are submitted to various interactions. Understanding the formation process of a phase alone, here ettringite, is the first step to later understand the much more complex reactions happening in cement. This study is crucial for the comprehension of early cement hydration and physical behavior. Indeed formation of hydrates, in particular, ettringite, will have an influence on the rheological properties of the cement paste and on the need for admixtures. To make progress toward the understanding of existing phenomena, a specific study of nucleation and growth processes of ettringite was conducted. First ettringite nucleation was studied in ionic aqueous solutions, with controlled but different experimental conditions, as different supersaturation degrees (β), different pH or presence of exogenous ions. Through induction time measurements, interfacial ettringite crystals solution energies (γ) were determined. Growth of ettringite in supersaturated solutions was also studied through chain crystallization reactions. Specific BET surface area measurements and Scanning Electron Microscopy observations seemed to prove that growth process is favored over the nucleation process when ettringite crystals are initially present in a solution with a low supersaturation degree. The influence of stirring on ettringite formation was also investigated. Observation was made that intensity and nature of stirring have a high influence on the size of ettringite needles formed. Needle sizes vary from less than 10µm long depending on the stirring to almost 100µm long without any stirring. During all previously mentioned experiments, initially present ions are consumed to form ettringite in such a way that the supersaturation degree with regard to ettringite is decreasing over time. To avoid this phenomenon a device compensating the drop of ion concentrations by adding some more solutions, and therefore always have constant ionic concentrations, was used. This constant β recreates the conditions of the beginning of cement paste hydration, when the dissolution of solid reagents compensates the consumption of ions to form hydrates. This device allowed the determination of the ettringite precipitation rate as a function of the supersaturation degree β. Taking samples at different time during ettringite precipitation and doing BET measurements allowed the determination of the interfacial growth rate of ettringite in m²/s. This work will lead to a better understanding and control of ettringite formation alone and thus during cements hydration. This study will also ultimately define the impact of ettringite formation process on the rheology of cement pastes at early age, which is a crucial parameter from a practical point of view.

Keywords: cement hydration, ettringite, morphology of crystals, nucleation-growth process

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Authors: A. V. Harutyunyan

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The investigation results of rocks at high pressures and temperatures have revealed the intervals of changes of seismic waves and density, as well as some processes taking place in rocks. In the serpentinized rocks, as a consequence of dehydration, abrupt changes in seismic waves and density have been recorded. Hydrogen-bearing components are released which combine with carbon-bearing components. As a result, hydrocarbons formed. The investigated samples are smelted. Then, geofluids and hydrocarbons migrate into the upper horizons of the Earth crust by the deep faults. Then their differentiation and accumulation in the jointed rocks of the faults and in the layers with collecting properties takes place. Under the majority of the hydrocarbon deposits, at a certain depth, magmatic centers and deep faults are recorded. The investigation results of the serpentinized rocks with numerous geological-geophysical factual data allow understanding that hydrocarbons are mainly formed in both the offshore part of the ocean and at different depths of the continental crust. Experiments have also shown that the dehydration of the serpentinized rocks is accompanied by an explosion with the instantaneous increase in pressure and temperature and smelting the studied rocks. According to numerous publications, hydrocarbons and diamonds are formed in the upper part of the mantle, at the depths of 200-400km, and as a consequence of geodynamic processes, they rise to the upper horizons of the Earth crust through narrow channels. However, the genesis of metamorphogenic diamonds and the diamonds found in the lava streams formed within the Earth crust, remains unclear. As at dehydration, super high pressures and temperatures arise. It is assumed that diamond crystals are formed from carbon containing components present in the dehydration zone. It can be assumed that besides the explosion at dehydration, secondary explosions of the released hydrogen take place. The process is naturally accompanied by seismic phenomena, causing earthquakes of different magnitudes on the surface. As for the diamondiferous kimberlites, it is well-known that the majority of them are located within the ancient shield and platforms not obligatorily connected with the deep faults. The kimberlites are formed at the shallow location of dehydrated masses in the Earth crust. Kimberlites are younger in respect of containing ancient rocks containing serpentinized bazites and ultrbazites of relicts of the paleooceanic crust. Sometimes, diamonds containing water and hydrocarbons showing their simultaneous genesis are found. So, the geofluids, hydrocarbons and diamonds, according to the new concept put forward, are formed simultaneously from serpentinized rocks as a consequence of their dehydration at different depths of the Earth crust. Based on the concept proposed by us, we suggest discussing the following: -Genesis of gigantic hydrocarbon deposits located in the offshore area of oceans (North American, Mexican Gulf, Cuanza-Kamerunian, East Brazilian etc.) as well as in the continental parts of different mainlands (Kanadian-Arctic Caspian, East Siberian etc.) - Genesis of metamorphogenic diamonds and diamonds in the lava streams (Guinea-Liberian, Kokchetav, Kanadian, Kamchatka-Tolbachinian, etc.).

Keywords: dehydration, diamonds, hydrocarbons, serpentinites

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Authors: Sergey A. Lurie, Yury O. Solyaev, Dmitry B. Volkov-Bogorodsky, Alexander V. Volkov

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The media with voids is considered and the method of the analytical estimation of the effective mechanical properties in the theory of elastic materials with voids is proposed. The variational model of the porous media is discussed, which is based on the model of the media with fields of conserved dislocations. It is shown that this model is fully consistent with the known model of the linear elastic materials with voids. In the present work, the generalized model of the porous media is proposed in which the specific surface properties are associated with the field of defects-pores in the volume of the deformed body. Unlike typical surface elasticity model, the strain energy density of the considered model includes the special part of the surface energy with the quadratic form of the free distortion tensor. In the result, the non-classical boundary conditions take modified form of the balance equations of volume and surface stresses. The analytical approach is proposed in the present work which allows to receive the simple enough engineering estimations for effective characteristics of the media with free dilatation. In particular, the effective flexural modulus and Poisson's ratio are determined for the problem of a beam pure bending. Here, the known voids elasticity solution was expanded on the generalized model with the surface effects. Received results allow us to compare the deformed state of the porous beam with the equivalent classic beam to introduce effective bending rigidity. Obtained analytical expressions for the effective properties depend on the thickness of the beam as a parameter. It is shown that the flexural modulus of the porous beam is decreased with an increasing of its thickness and the effective Poisson's ratio of the porous beams can take negative values for the certain values of the model parameters. On the other hand, the effective shear modulus is constant under variation of all values of the non-classical model parameters. Solutions received for a beam pure bending and the hydrostatic loading of the porous media are compared. It is shown that an analytical estimation for the bulk modulus of the porous material under hydrostatic compression gives an asymptotic value for the effective bulk modulus of the porous beam in the case of beam thickness increasing. Additionally, it is shown that the scale effects appear due to the surface properties of the porous media. Obtained results allow us to offer the procedure of an experimental identification of the non-classical parameters in the theory of the linear elastic materials with voids based on the bending tests for samples with different thickness. Finally, the problem of implementation of the Saint-Venant hypothesis for the transverse stresses in the porous beam are discussed. These stresses are different from zero in the solution of the voids elasticity theory, but satisfy the integral equilibrium equations. In this work, the exact value of the introduced surface parameter was found, which provides the vanishing of the transverse stresses on the free surfaces of a beam.

Keywords: effective properties, scale effects, surface defects, voids elasticity

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