Search results for: rare and endengered plants (REPs)

Authors: N. Zarghami, M. Mohammadinejad, A. Akbarzadeh, Y. Pilehvar-Soltanahmadi, F. Zarghami

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Breast cancer is known to be the most common cancer in women. Cyclin D1 is a proto-oncogene and over expression of cyclin D1 is directly associated with tumorgenesis. Cyclin D1 is overexpressed in more than 50% of breast cancer cases. Curcumin is derived from turmeric (curcuma longa) and chrysin is a component that could be extracted from many plants and honey. These two plants derived compounds are believed to assist in inhibition of the cancer cells growth and reducing cyclin D1 expression. In this work, the hypothesis is to combine curcumin and chrysin in order to analyze the potential synergistic effect in inhibition of cell proliferation and down regulation of cyclin D1. In addition, use of PLGA-PEG to improve bioavailability of pure curcumin and chrysin, while reinforcing the potential effect of this combination. PLGA-PEG nanoparticles were synthesized and characterized with FT-IR and 1HNMR methods. Although morphological features were analyzed by SEM. Afterward curcumin and chrysin were encapsulated with synthesized PLGA-PEG and MTT-assay was performed to measure cytotoxicity effect of these plant constitutes. T-47D cells were treated with proper concentration of these constituents and Real-time PCR was carried out to evaluate cyclin D1 expression levels. Curcumin, chrysin and combination of curcumin –chrysin in intact and nano-capsulated form affected T-47D cells in time and dose dependent manner and the combination of these compounds had synergistic effects. Real-time PCR results, revealed that curcumin, chrysin and combination of curcumin-chrysin in pure and encapsulated form inhibited cyclin D1 expression. Compared to pure components, different concentrations of nano-curcumin, nano chrysin and nano-combination caused further decline in cyclin D12 expression by 5-11%, 8-22% and 6-18% respectively. Our results demonstrated that, combination of chrysin-curcumin had synergistic effect and nano capsulated form of this component had grater inhibition on cyclin D1 expression.

Keywords: breast cancer, cyclin D1, curcumin, chrysin, nanoparticles

Procedia PDF Downloads 273

Authors: Mebruka Mohammed, Daniel Bisrat, Asfaw Debella, Tarekegn Birhanu

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Lack of quality control standards for medicinal plants and their preparations is considered major barrier to their integration in to effective primary health care in Ethiopia. Poor quality herbal preparations led to countless adverse reactions extending to death. Denial of penetration for the Ethiopian medicinal plants in to the world’s booming herbal market is also another significant loss resulting from absence of herbal quality control system. Thus, in the present study, Gnidia stenophylla Gilg (popular antimalarial plant of south eastern Ethiopia), is standardized and a full monograph is produced that can serve as a guideline in quality control of the crude drug. Morphologically, the roots are found to be cylindrical and tapering towards the end. It has a hard, corky and friable touch with saddle brown color externally and it is relatively smooth and pale brown internally. It has got characteristic pungent odor and very bitter taste. Microscopically it has showed lignified xylem vessels, wider medullary rays with some calcium oxalate crystals, reddish brown secondary metabolite contents and slender shaped long fibres. Physicochemical standards quantified and resulted: foreign matter (5.25%), moisture content (6.69%), total ash (40.80%), acid insoluble ash (8.00%), water soluble ash (2.30%), alcohol soluble extractive (15.27%), water soluble extractive (10.98%), foaming index (100.01 ml/g), swelling index (7.60 ml/g). Phytochemically: Phenols, flavonoids, steroids, tannins and saponins were detected in the root extract; TLC and HPLC fingerprints were produced and an analytical marker was also tentatively characterized as 3-(3,4-dihydro-3,5-dihydroxy-2-(4-hydroxy-5-methylhex-1-en-2-yl)-7-methoxy-4-oxo-2H-chromen-8-yl)-5-hydroxy-2-(4-hydroxyphenyl)-7-methoxy-4H-chromen-4-one. Residue wise pesticides (i.e. DDT, DDE, g-BHC) and radiochemical levels fall below the WHO limit while Heavy metals (i.e. Co, Ni, Cr, Pb, and Cu), total aerobic count and fungal load lie way above the WHO limit. In conclusion, the result can be taken as signal that employing non standardized medicinal plants could cause many health risks of the Ethiopian people and Africans’ at large (as 80% of inhabitants in the continent depends on it for primary health care). Therefore, following a more universal approach to herbal quality by adopting the WHO guidelines and developing monographs using the various quality parameters is inevitable to minimize quality breach and promote effective herbal drug usage.

Keywords: Gnidia stenophylla Gilg, standardization/monograph, pharmacognostic, residue/impurity, quality

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Authors: Safia Hocine, Djamil Aïssani

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Risk models, recently studied in the literature, are becoming increasingly complex. It is rare to find explicit analytical relations to calculate the ruin probability. Indeed, the stability issue occurs naturally in ruin theory, when parameters in risk cannot be estimated than with uncertainty. However, in most cases, there are no explicit formulas for the ruin probability. Hence, the interest to obtain explicit stability bounds for these probabilities in different risk models. In this paper, we interest to the stability bounds of the univariate classical risk model established using the regenerative processes approach. By adopting an algorithmic approach, we implement this approximation and determine numerically the bounds of ruin probability in the case of large claims (heavy-tailed distribution).

Keywords: heavy-tailed distribution, large claims, regenerative process, risk model, ruin probability, stability

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Authors: Vesna Pungercar, Florian Musso

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Identifying materials that can substitute rare or expensive natural resources is one of the key challenges for improving resource efficiency in the building sector. With a growing world population and rising living standards, more and more salt is produced as waste through seawater desalination and potash mining processes. Unfortunately, most of the salt is directly disposed of into nature, where it causes environmental pollution. On the other hand, salt is affordable, is used therapeutically in various respiratory treatments, and can store humidity and heat. It was, therefore, necessary to determine salt materials already in use in building construction and their hygrothermal properties. This research aims to identify salt materials from different scientific branches and historically, to investigate their properties and prioritize the most promising salt materials for indoor applications in a thermal envelope. This was realized through literature review and classification of salt materials into three groups (raw salt materials, composite salt materials, and processed salt materials). The outcome of this research shows that salt has already been used as a building material for centuries and has a potential for future applications due to its hygrothermal properties in a thermal envelope.

Keywords: salt, building material, hygrothermal properties, environment

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Authors: Pradip Baishya, D. K. Mahanta

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Rapid and unplanned urbanisation in most cities of India has progressively increased the problem of managing municipal waste in the past few years. With insufficient infrastructure and funds, Municipalities in most cities are struggling to cope with the pace of waste generated. Open dumping is widely in practice as a cheaper option. Scientific disposal of waste in such a large scale with the elements of segregation, recycling, landfill, and incineration involves sophisticated and expensive plants. In an effort to finding affordable and simple solutions to address this burning issue of waste disposal, a semi-mechanized plant has been designed underlying the concept of a zero waste community. The fabrication work of the waste management unit is carried out by local skills from locally available materials. A resident colony in the city of Guwahati has been chosen, which is seen as a typical representative of most cities in India in terms of size and key issues surrounding waste management. Scientific management and disposal of waste on site is carried out on the principle of reduce, reuse and recycle from segregation to compositing. It is a local community participatory model, which involves all stakeholders in the process namely rag pickers, residents, municipality and local industry. Studies were conducted to testify the plant as revenue earning self-sustaining model in the long term. Current working efficiency of plant for segregation was found to be 1kg per minute. Identifying bottlenecks in the success of the model, data on efficiency of the plant, economics of its fabrication were part of the study. Similar satellite waste management plants could potentially be a solution to supplement the waste management system of municipalities of similar sized cities in India or South East Asia with similar issues surrounding waste disposal.

Keywords: affordable, rag pickers, recycle, reduce, reuse, segregation, zero waste

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Authors: Laura Gleason, Sahithi Talasila, Lauren Banner, Ladan Afifi, Neda Nikbakht

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Primary cutaneous anaplastic large cell lymphoma (pcALCL) accounts for 9% of all cutaneous T-cell lymphomas. pcALCL is classically characterized as a solitary papulonodule that often enlarges, ulcerates, and can be locally destructive, but overall exhibits an indolent course with overall 5-year survival estimated to be 90%. Distinguishing pcALCL from systemic ALCL (sALCL) is essential as sALCL confers a poorer prognosis with average 5-year survival being 40-50%. Although extremely rare, there have been several cases of ALK-positive ALCL diagnosed on skin biopsy without evidence of systemic involvement, which poses several challenges in the classification, prognostication, treatment, and follow-up of these patients. Objectives: We present a case of cutaneous ALK-positive ALCL without evidence of systemic involvement, and a narrative review of the literature to further characterize that ALK-positive ALCL limited to the skin is a distinct variant with a unique presentation, history, and prognosis. A 30-year-old woman presented for evaluation of an erythematous-violaceous papule present on her right chest for two months. With the development of multifocal disease and persistent lymphadenopathy, a bone marrow biopsy and lymph node excisional biopsy were performed to assess for systemic disease. Both biopsies were unrevealing. The patient was counseled on pursuing systemic therapy consisting of Brentuximab, Cyclophosphamide, Doxorubicin, and Prednisone given the concern for sALCL. Apropos of the patient we searched for clinically evident, cutaneous ALK-positive ALCL cases, with and without systemic involvement, in the English literature. Risk factors, such as tumor location, number, size, ALK localization, ALK translocations, and recurrence, were evaluated in cases of cutaneous ALK-positive ALCL. The majority of patients with cutaneous ALK-positive ALCL did not progress to systemic disease. The majority of cases that progressed to systemic disease in adults had recurring skin lesions and cytoplasmic localization of ALK. ALK translocations did not influence disease progression. Mean time to disease progression was 16.7 months, and significant mortality (50%) was observed in those cases that progressed to systemic disease. Pediatric cases did not exhibit a trend similar to adult cases. In both the adult and pediatric cases, a subset of cutaneous-limited ALK-positive ALCL were treated with chemotherapy. All cases treated with chemotherapy did not progress to systemic disease. Apropos of an ALK-positive ALCL patient with clinical cutaneous limited disease in the histologic presence of systemic markers, we discussed the literature data, highlighting the crucial issues related to developing a clinical strategy to approach this rare subtype of ALCL. Physicians need to be aware of the overall spectrum of ALCL, including cutaneous limited disease, systemic disease, disease with NPM-ALK translocation, disease with ALK and EMA positivity, and disease with skin recurrence.

Keywords: anaplastic large cell lymphoma, systemic, cutaneous, anaplastic lymphoma kinase, ALK, ALCL, sALCL, pcALCL, cALCL

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Authors: Fabio R. Pires, Paulo R. C. C. Ribeiro, Douglas G. Viana, Robson Bonomo, Fernando B. Egreja Filho, Alberto Cargnelutti Filho, Luiz F. Martins, Leila B. S. Cruz, Mauro C. P. Nascimento

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The use of barite (BaSO₄) as a weighting agent in drilling fluids for oil and gas activities makes barium a potential contaminant in the case of spills onto flooded soils, where barium sulfate solubility is increased due to low redox conditions. In order to select plants able to remove barium in such scenarios, seven plant species were evaluated on barium phytoextraction capacity: Brachiaria arrecta; Cyperus cf. papyrus; Eleocharis acutangula; Eleocharis interstincta; Nephrolepsis cf. rivularis; Paspalum conspersum and Typha domingensis. Plants were grown in pots with 13 kg of soil each, and exposed to six barium concentrations (established with BaCl₂): 0; 2.5; 5.0; 10.0; 30.0; 65.0 mg kg-1. To simulate flooding conditions, every pot was manteined with a thin irrigation water depth over soil surface (~1.0 cm). Treatments were carried out in triplicate, and pots were distributed randomly inside the greenhouse. Biometric and chemical analyses were performed throughout the experiment, including Ba²⁺ accumulation in shoots and roots. The highest amount of barium was observed in T. domingensis biomass, followed by C. cf. papyrus. However, the latter exported most of the barium to shoot, especially in higher BaCl₂ doses, while the former accumulated barium preferentially in roots. Thus, barium removal with C. cf. papyrus could be achieved by simply harvesting aerial biomass. The amount of barium in C. cf. papyrus was a consequence of high biomass production rather than barium concentration in plant tissues, whereas T. domingensis showed high barium concentration in plant tissues and high biomass production as well. These results make T. domingensis and C. cf. papyrus potential candidates to be applied in phytoremediation schemes to remove barium from flooded soils.

Keywords: barium sulfate, cyperus, drilling fluids, phytoextraction, Typha

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Authors: Chetneti Srisa-an

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In Knowledge and Data Engineering field, relational database is the best repository to store data in a real world. It has been using around the world more than eight decades. Normalization is the most important process for the analysis and design of relational databases. It aims at creating a set of relational tables with minimum data redundancy that preserve consistency and facilitate correct insertion, deletion, and modification. Normalization is a major task in the design of relational databases. Despite its importance, very few algorithms have been developed to be used in the design of commercial automatic normalization tools. It is also rare technique to do it automatically rather manually. Moreover, for a large and complex database as of now, it make even harder to do it manually. This paper presents a new complete automated relational database normalization method. It produces the directed graph and spanning tree, first. It then proceeds with generating the 2NF, 3NF and also BCNF normal forms. The benefit of this new algorithm is that it can cope with a large set of complex function dependencies.

Keywords: relational database, functional dependency, automatic normalization, primary key, spanning tree

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Authors: Zainab Shaikh, Yusuf Miyanji

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Pilomatrixoma is a benign neoplasm of the hair follicle matrix that is not commonly diagnosed in general practice. This is a case report of a 9-year-old boy who presented with a one-year history of a 19mm x 11 mm swelling in the left infra-orbital region. This was previously undiagnosed in Spain, where the patient resided at the time of initial presentation, due to the language barrier the patient’s family encountered. An ultrasound and magnetic resonance imaging gave useful information regarding surrounding structures for complete tumor excision and indicated that the risk of facial nerve palsy is low. The lesion was surgically excised and a definitive diagnosis was made after histopathology. Pilomatrixoma, although not rare in its occurrence, is rarely this large at the time of excision due to early presentation. This case highlights the importance of including pilomatrixoma in the differential diagnosis of dermal and subcutaneous lesions in the head and neck region, as it is often misdiagnosed due to the lack of awareness of its clinical presentation.

Keywords: pilomatrixoma, swelling, infra-orbital, facial swelling

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Authors: Umut Çınar

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The fact that ozone gas has color bleaching properties has made the use of ozone gas widespread in the textile sector as well as in many other sectors. Ozone gas, which is a strong oxidative agent on the fabric, causes the paint on the fabric to wear off and lighten its color with an aged appearance. Within the scope of this thesis, parameters affecting the bleaching properties of ozone gas on reactive dyed knitted fabric, which is rare in the literature, were investigated. Ozone concentration, time, and pH values were analyzed with the Box Behnken experimental design method, and optimum conditions were determined. After the experiments, wear and opacity values were measured with the help of a spectrophotometer. With the help of the Design Expert program, the graphics related to the data were prepared and interpreted with Box Behnken and ANOVA. These experiments on reactive dyed knitted fabric were tested on these parameters, and the spectrophotometric values of the fabric and optimum parameters in abrasion and opacity were revealed.

Keywords: ozone, reactive dye, bleaching, textile, garment wash, sustainability, washing, Box–Behnken, experimental design

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Authors: Ana C. Ramos Valdivia, Ileana Vera-Reyes, Ariana A. Huerta-Heredia

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The conditions of biotic and abiotic stress in plants can lead to the generation of high amounts of reactive oxygen species (ROS), which leads through a signaling cascade and second messengers to different antioxidant defense responses including the production of secondary metabolites. A limited number of species of plants like Uncaria tomentosa (cat claw) typical of the Amazon region produce monoterpenoid oxindole alkaloids (MOA) such as isopteropodine, mitraphylline, rhynchophylline and its isomers. Moreover, in cultivated roots, the glucoindole alkaloid 3α-dihydrocadambine (DHC) is also accumulated. Several studies have demonstrated that MAO has antioxidant properties and possess important pharmacological activities such as antitumor and immunostimulant while DHC, has hypotensive and hypolipidemic effects. In order the study the regulatory concerns operating in MAO production, the links between oxidative stress and antioxidant alkaloid production in U. tomentosa root cultures were examined. Different amount of hydrogen peroxide between 0.2 -1.0 mM was added to 12 days old roots cultures showing that, this substance had a differential effect on the production of DHC and MOA whereas the viability remained in 80% after six days. Addition of 0.2 mM hydrogen peroxide increased approximately 65% MAO and DHC production (0,540 ± 0.018 and 0.618 ± 0.029 mg per g dry weight, respectively) relative to the control. On contrast, after the addition of 0.6 mM and 1 mM hydrogen peroxide, DHC accumulation into the roots gradually decreased to 53% and 93% respectively, without changes in MAO concentration, which was in relation to a twice increase of the intracellular hydrogen peroxide content. On the other hand, concentrations of DHC (0.1, 0.5 and 1.0 mM in methanol) demonstrated free-radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The calculated IC50 for all tested concentrations was 0.180 mg per ml (0.33 mM) while the calculated TE50 was 276 minutes. Our results suggest that U. tomentosa root cultures both MAO and DHC have antioxidant capacities and respond to oxidative stress with a stimulation of their production; however, in presence of a higher concentration of ROS into the roots, DHC could be oxidized.

Keywords: monoterpenoid indole alkaloid, oxidative stress, root cultures, uncaria tomentosa

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Authors: Demet Ozgur-Unluakin, Busenur Turkali, S. Caglar Aksezer

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Since the age of industrialization, maintenance has always been a very crucial element for all kinds of factories and plants. With today’s increasingly developing technology, the system structure of such facilities has become more complicated, and even a small operational disruption may return huge losses in profits for the companies. In order to reduce these costs, effective maintenance planning is crucial, but at the same time, it is a difficult task because of the complexity of systems. The most important aspect of correct maintenance planning is to understand the structure of the system, not to ignore the dependencies among the components and as a result, to model the system correctly. In this way, it will be better to understand which component improves the system more when it is maintained. Undoubtedly, proactive maintenance at a scheduled time reduces costs because the scheduled maintenance prohibits high losses in profits. But the necessity of corrective maintenance, which directly affects the situation of the system and provides direct intervention when the system fails, should not be ignored. When a fault occurs in the system, if the problem is not solved immediately and proactive maintenance time is awaited, this may result in increased costs. This study proposes various maintenance methods with different efficiency measures under corrective maintenance strategy on a subsystem of a thermal power plant. To model the dependencies between the components, dynamic Bayesian Network approach is employed. The proposed maintenance methods aim to minimize the total maintenance cost in a planning horizon, as well as to find the most appropriate component to be attacked on, which improves the system reliability utmost. Performances of the methods are compared under corrective maintenance strategy. Furthermore, sensitivity analysis is also applied under different cost values. Results show that all fault effect methods perform better than the replacement effect methods and this conclusion is also valid under different downtime cost values.

Keywords: dynamic Bayesian networks, maintenance, multi-component systems, reliability

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Authors: Chinumani Choudhury

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Heavy metal contamination is an alarming problem, which poses a serious risk to human health and the surrounding geology. Soils get contaminated with heavy metals due to the un-regularized industrial discharge of the toxic metal-rich effluents. Under such a condition, the remediation of the contaminated sites becomes imperative for a sustainable, safe, and healthy environment. Phytoextraction, which involves the removal of heavy metals from the soil through root absorption and uptake, is a viable remediation technique, which ensures extraction of the toxic inorganic compound available in the soil even at low concentrations. The soil present in the Silghat Region of Assam, India, is mostly contaminated with Zinc (Zn) and Lead (Pb), having concentrations as high as to cause a serious environmental problem if proper measures are not taken. In the present study, an extensive experimental study was carried out to understand the effectiveness of two commonly planted trees in Assam, namely, i) Indian Pennywort and ii) Fenugreek, in the removal of heavy metals from the contaminated soil. The basic characterization of the soil in the contaminated site of the Silghat region was performed and the field concentration of Zn and Pb was recorded. Various long-term laboratory pot tests were carried out by sowing the seeds of Indian Pennywort and Fenugreek in a soil, which was spiked, with a very high dosage of Zn and Pb. The tests were carried out for different concentration of a particular heavy metal and the individual effectiveness in the absorption of the heavy metal by the plants were studied. The concentration of the soil was monitored regularly to assess the rate of depletion and the simultaneous uptake of the heavy metal from the soil to the plant. The amount of heavy metal uptake by the plant was also quantified by analyzing the plant sample at the end of the testing period. Finally, the study throws light on the applicability of the studied plants in the field for effective remediation of the contaminated sites of Assam.

Keywords: phytoextraction, heavy-metals, Indian pennywort, fenugreek

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Authors: Nahia H. Sassine, Frédéric-Victor Donzé, Arnaud Bruch, Barthélemy Harthong

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Thermal Energy Storage (TES) systems are central elements of various types of power plants operated using renewable energy sources. Packed bed TES can be considered as a cost–effective solution in concentrated solar power plants (CSP). Such a device is made up of a tank filled with a granular bed through which heat-transfer fluid circulates. However, in such devices, the tank might be subjected to catastrophic failure induced by a mechanical phenomenon known as thermal ratcheting. Thermal stresses are accumulated during cycles of loading and unloading until the failure happens. For instance, when rocks are used as storage material, the tank wall expands more than the solid medium during charge process, a gap is created between the rocks and tank walls and the filler material settles down to fill it. During discharge, the tank contracts against the bed, resulting in thermal stresses that may exceed the wall tank yield stress and generate plastic deformation. This phenomenon is repeated over the cycles and the tank will be slowly ratcheted outward until it fails. This paper aims at studying the evolution of tank wall stresses over granular bed thermal cycles, taking into account both thermal and mechanical loads, with a numerical model based on the discrete element method (DEM). Simulations were performed to study two different thermal configurations: (i) the tank is heated homogeneously along its height or (ii) with a vertical gradient of temperature. Then, the resulting loading stresses applied on the tank are compared as well the response of the internal granular material. Besides the study of the influence of different thermal configurations on the storage tank response, other parameters are varied, such as the internal angle of friction of the granular material, the dispersion of particles diameters as well as the tank’s dimensions. Then, their influences on the kinematics of the granular bed submitted to thermal cycles are highlighted.

Keywords: discrete element method (DEM), thermal cycles, thermal energy storage, thermocline

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Authors: Augustas Vaitkevicius, Mikhail Korjik, Eugene Tretyak, Ekaterina Trusova, Gintautas Tamulaitis

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Silicate materials are widely used as luminescent materials in amorphous and crystalline phase. Lithium silicate glass is popular for making neutron sensitive scintillation glasses. Cerium-doped single crystalline silicates of rare earth elements and yttrium have been demonstrated to be good scintillation materials. Due to their high thermal and photo-stability, silicate glass ceramics are supposed to be suitable materials for producing light converters for high power white light emitting diodes. In this report, the influence of glass composition and crystallization on photoluminescence (PL) of different silicate glasses was studied. Barium (BaO-2SiO₂) and lithium (Li₂O-2SiO₂) glasses were under study. Cerium, dysprosium, erbium and europium ions as well as their combinations were used for doping. The influence of crystallization was studied after transforming the doped glasses into glass ceramics by heat treatment in the temperature range of 550-850 degrees Celsius for 1 hour. The study was carried out by comparing the photoluminescence (PL) spectra, spatial distributions of PL parameters and quantum efficiency in the samples under study. The PL spectra and spatial distributions of their parameters were obtained by using confocal PL microscopy. A WITec Alpha300 S confocal microscope coupled with an air cooled CCD camera was used. A CW laser diode emitting at 405 nm was exploited for excitation. The spatial resolution was in sub-micrometer domain in plane and ~1 micrometer perpendicularly to the sample surface. An integrating sphere with a xenon lamp coupled with a monochromator was used to measure the external quantum efficiency. All measurements were performed at room temperature. Chromatic properties of the light emission from the glasses and glass ceramics have been evaluated. We observed that the quantum efficiency of the glass ceramics is higher than that of the corresponding glass. The investigation of spatial distributions of PL parameters revealed that heat treatment of the glasses leads to a decrease in sample homogeneity. In the case of BaO-2SiO₂: Eu, 10 micrometer long needle-like objects are formed, when transforming the glass into glass ceramics. The comparison of PL spectra from within and outside the needle-like structure reveals that the ratio between intensities of PL bands associated with Eu²⁺ and Eu³⁺ ions is larger in the bright needle-like structures. This indicates a higher degree of crystallinity in the needle-like objects. We observed that the spectral positions of the PL bands are the same in the background and the needle-like areas, indicating that heat treatment imposes no significant change to the valence state of the europium ions. The evaluation of chromatic properties confirms applicability of the glasses under study for fabrication of white light sources with high thermal stability. The ability to combine barium and lithium glass matrixes and doping by Eu, Ce, Dy, and Tb enables optimization of chromatic properties.

Keywords: glass ceramics, luminescence, phosphor, silicate

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Authors: Emna Abid, Linda Chebbi, Yosra Mabrouk, Amel Labidi, Lamia Mansour

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Werner syndrome (WS) is a rare genetic disorder inherited in an autosomal recessive pattern characterized by accelerated aging. While extensive research has been conducted on its systemic manifestations, the specific dental implications of WS remain poorly understood. The medical history and the oral health status of two patients diagnosed with WS were detailed. Our findings revealed a high prevalence of dental problems in both patients, including periodontitis, xerostomia, and temporomandibular joint disorders. This article aims to investigate the dental challenges faced by individuals with WS as well as the prosthetic options envisaged through two clinical cases contributing to a deeper understanding of the dental implications of WS and to choose the appropriate prosthetic solution in this population. Future research should focus on larger scale studies and clinical trials to validate these proposed strategies.

Keywords: adult progeria, clinical symptoms, oral manifestations, dental care, prosthetic management

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Authors: Anna Bohers, Emília Hroncová, Juraj Ladomerský

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Oil sludge with its main characteristic of high acidity is a waste product generated from the operation of refinery and petrochemical plants. Former refinery and petrochemical plant - Petrochema Dubová is present in Slovakia as well. Its activities was to process the crude oil through sulfonation and adsorption technology for production of lubricating and special oils, synthetic detergents and special white oils for cosmetic and medical purposes. Seventy years ago – period, when this historical acid sludge burden has been created – comparing to the environmental awareness the production was in preference. That is the reason why, as in many countries, also in Slovakia a historical environmental burden is present until now – 229 211 m3 of oil sludge in the middle of the National Park of Nízke Tatry mountain chain. Neither one of tried treatment methods – bio or non-biologic one - was proved as suitable for processing or for recovery in the reason of different factors admission: i.e. strong aggressivity, difficulty with handling because of its sludgy and liquid state et sim. As a potential solution, also incineration was tested, but it was not proven as a suitable method, as the concentration of SO2 in combustion gases was too high, and it was not possible to decrease it under the acceptable value of 2000 mg.mn-3. That is the reason why the operation of incineration plant has been terminated, and the acid sludge landfills are present until nowadays. The objective of this paper is to present a new possibility of processing and valorization of acid sludgy-waste. The processing of oil sludge was performed through the effective separation - thermal desorption technology, through which it is possible to split the sludgy material into the matrix (soil, sediments) and organic contaminants. In order to boost the efficiency in the processing of acid sludge through thermal desorption, the work will present the possibility of application of an original technology – Method of Blowing Decomposition for recovering of organic matter into technological lubricating oil.

Keywords: hazardous waste, oil sludge, remediation, thermal desorption

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Authors: Khairani Binti Supyan, Fatimah Khalid, Mas Rina Mustaffa, Azreen Bin Azman, Amirul Azuani Romle

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Perennial plant classification plays a significant role in various agricultural and environmental applications, assisting in plant identification, disease detection, and biodiversity monitoring. Nevertheless, attaining high accuracy in perennial plant image classification remains challenging due to the complex variations in plant appearance, the diverse range of environmental conditions under which images are captured, and the inherent variability in image quality stemming from various factors such as lighting conditions, camera settings, and focus. This paper proposes an adaptation approach to optimize perennial plant image classification by fine-tuning the pre-trained DNNs model. This paper explores the efficacy of fine-tuning prevalent architectures, namely VGG16, ResNet50, and InceptionV3, leveraging transfer learning to tailor the models to the specific characteristics of perennial plant datasets. A subset of the MYLPHerbs dataset consisted of 6 perennial plant species of 13481 images under various environmental conditions that were used in the experiments. Different strategies for fine-tuning, including adjusting learning rates, training set sizes, data augmentation, and architectural modifications, were investigated. The experimental outcomes underscore the effectiveness of fine-tuning deep neural networks for perennial plant image classification, with ResNet50 showcasing the highest accuracy of 99.78%. Despite ResNet50's superior performance, both VGG16 and InceptionV3 achieved commendable accuracy of 99.67% and 99.37%, respectively. The overall outcomes reaffirm the robustness of the fine-tuning approach across different deep neural network architectures, offering insights into strategies for optimizing model performance in the domain of perennial plant image classification.

Keywords: perennial plants, image classification, deep neural networks, fine-tuning, transfer learning, VGG16, ResNet50, InceptionV3

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Authors: Andreas Schomburg, Claire Le Bayon, Claire Guenat, Philip Brunner

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Numerous river restoration projects have been established in Switzerland in recent years after decades of human activity in floodplains. The success of restoration projects in terms of biodiversity and ecosystem functions largely depend on the development of the floodplain soil system. Plants and earthworms as ecosystem engineers are known to be able to build up a stable soil structure by incorporating soil organic matter into the soil matrix that creates water stable soil aggregates. Their engineering efficiency however largely depends on changing soil properties and frequent floods along an evolutive floodplain transect. This study, therefore, aims to quantify the effect of flood frequency and duration as well as of physico-chemical soil parameters on plants’ and earthworms’ engineering efficiency. It is furthermore predicted that these influences may have a different impact on one of the engineers that leads to a varying contribution to aggregate formation within the floodplain transect. Ecosystem engineers were sampled and described in three different floodplain habitats differentiated according to the evolutionary stages of the vegetation ranging from pioneer to forest vegetation in a floodplain restored 15 years ago. In addition, the same analyses were performed in an embanked adjacent pasture as a reference for the pre-restored state. Soil aggregates were collected and analyzed for their organic matter quantity and quality using Rock Eval pyrolysis. Water level and discharge measurements dating back until 2008 were used to quantify the return period of major floods. Our results show an increasing amount of water stable aggregates in soil with increasing distance to the river and show largest values in the reference site. A decreasing flood frequency and the proportion of silt and clay in the soil texture explain these findings according to F values from one way ANOVA of a fitted mixed effect model. Significantly larger amounts of labile organic matter signatures were found in soil aggregates in the forest habitat and in the reference site that indicates a larger contribution of plants to soil aggregation in these habitats compared to the pioneer vegetation zone. Earthworms’ contribution to soil aggregation does not show significant differences in the floodplain transect, but their effect could be identified even in the pioneer vegetation with its large proportion of coarse sand in the soil texture and frequent inundations. These findings indicate that ecosystem engineers seem to be able to create soil aggregates even under unfavorable soil conditions and under frequent floods. A restoration success can therefore be expected even in ecosystems with harsh soil properties and frequent external disturbances.

Keywords: ecosystem engineers, flood frequency, floodplains, river restoration, rock eval pyrolysis, soil organic matter incorporation, soil structuration

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Authors: Kazam Ali, Muhammad Sagheer, Mansoor-Ul- Hasan, Abdul Rashid, Chaudhary Muhammad Shahid Hanif, Fawad Zafar Ahmad Khan, Hafiz Muhammad Aatif

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Natural extracts of two medicinal plants Nicotiana tabacum and Eucalyptus globulus were tested for their toxic and enzyme inhibition effects against three insects species of stored grains Tribolium castaneum, Trogoderma granarium and Sitophilus granarius. Responses of insects varied with exposure periods and dilution levels of acetone extracts of plants. Both plant extracts were lethal to insects but the crude leaf extract of N. tabacum evidenced strong toxic action against three tested insect species. Maximum mortality 36.30% in S. granarius, 25.96% in T. castaneum, and 21.88% in T. granarium were found at 20% dilution level, after 10 days exposure to botanical extract of N. tabacum. The impact of N. tabacum and E. globulus on the activity of esterases; acetylcholinesterase (AChE), α-carboxylesterase (α-CE), β-carboxylesterase (β-CE) and phosphatses; acid phosphatase (AcP), alkaline phosphatase (AlP) of three stored grain insect species were also studied in the survivors of toxicity assay. Whole body homogenates of insects were used for enzyme determination and consumption of high dose rate N. tabacum extract containing diet resulted in maximum 55.33% inhibition of AChE and 26.17% AlP inhibition in T. castaneum, while 44.17% of α-CE and 31.67% inhibition of β-CE activity were noted in S. granarius. Maximum inhibition 23.44% of AcP activity was found in T. granarium exposed to diet treated with the extract of E. globulus. The findings indicate that acetone extracts of N. tabacum and E. globulus are naturally occurring pesticide and facts of the enzyme inhibition relations specify that their effect changes with the insect species.

Keywords: natural extract, medicinal plant, toxic effects, enzyme inhibition, acetone extract

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Authors: Joshua Chew, Vesa Cheng, David Thomson

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Background: Hereditary angioedema (HAE) or C1 esterase deficiency is a relatively rare entity that has a potential for significant anesthetic complications. Methods: A literature review was performed of published cases of surgery in patients with HAE. Results were limited to English language only and cases were examined for management strategies and successful prevention of acute attacks. Results: The literature revealed the successful use of C1 esterase inhibitors as the most common agent in surgical prophylaxis therapy. Other therapeutic targets described included kallikrein inhibitors and bradykinin B2 receptor antagonists. Conclusions: Therapeutic targets that exist for the management of acute attacks in HAE have been successfully employed in the setting of surgery. The data is currently limited and could not be used as a firm evidence base, but the limited outcomes seen are positive and reassuring for the prospective anesthetic management of this potentially fatal condition.

Keywords: anesthesia, C1 esterase deficiency, hereditary angioedema, surgical prophylaxis

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Authors: D. Leibman, D. Wolf, A. Gal-On

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Viral diseases of tomato crops result in heavy yield losses and may even jeopardize the production of these crops. Classical tomato breeding for disease resistance against Tomato yellow leaf curl virus (TYLCV), leads to partial resistance associated with a number of recessive genes. To author’s best knowledge Pepino mosaic virus (PepMV) genetic resistance is not yet available. The generation of viral resistance by means of genetic engineering was reported and implemented for many crops, including tomato. Transgenic resistance against viruses is based, in most cases, on Post Transcriptional Gene Silencing (PTGS), an endogenous mechanism which destroys the virus genome. In this work, we developed immunity against PepMV and TYLCV in a tomato based on a PTGS mechanism. Tomato plants were transformed with a hairpin-construct-expressed transgene-derived double-strand-RNA (tr-dsRNA). In the case of PepMV, the binary construct harbored three consecutive fragments of the replicase gene from three different PepMV strains (Italian, Spanish and American), to provide resistance against a range of virus strains. In the case of TYLCV, the binary vector included three consecutive fragments of the IR, V2 and C2 viral genes constructed in a hairpin configuration. Selected transgenic lines (T0) showed a high accumulation of transgene siRNA of 21-24 bases, and T1 transgenic lines showed complete immunity to PepMV and TYLCV. Graft inoculation displayed immunity of the transgenic scion against PepMV and TYLCV. The study presents the engineering of resistance in tomato against two serious diseases, which will help in the production of high-quality tomato. However, unfortunately, these resistant plants have not been implemented due to public ignorance and opposition against breeding by genetic engineering.

Keywords: PepMV, PTGS, TYLCV, tr-dsRNA

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Authors: Abayomi O. Adetuyi, Jamiu M. Jabar, Samuel O. Afolabi

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Vegetable fibres are classes of fibres of low density, biodegradable and non-abrasive that are largely abundant fibre materials with specific properties and mostly found/ obtained in plants on earth surface. They are classified into three categories, depending on the part of the plant from which they are gotten from namely: fruit, Blast and Leaf fibre. Ever since four/five millennium B.C, attention has been focussing on the commonest and highly utilized cotton fibre obtained from the fruit of cotton plants (Gossypium spp), for the production of cotton fabric used in every home today. The present study, therefore, focused on the ability of three underutilized vegetable (fruit) fibres namely: coir fiber (Eleas coniferus), palm kernel fiber and empty fruit bunch fiber (Elias guinensis) through chemical modifications for better composite value addition performance to polyurethane form and dye adsorption. These fibres were sourced from their parents’ plants, identified and cleansed with 2% hot detergent solution 1:100, rinsed in distilled water and oven-dried to constant weight, before been chemically modified through alkali bleaching, mercerization and acetylation. The alkali bleaching involves treating 0.5g of each fiber material with 100 mL of 2% H2O2 in 25 % NaOH solution with refluxing for 2 h. While that of mercerization and acetylation involves the use of 5% sodium hydroxide NaOH solution for 2 h and 10% acetic acid- acetic anhydride 1:1 (v/v) (CH3COOH) / (CH3CO)2O solution with conc. H2SO4 as catalyst for 1 h, respectively on the fibres. All were subsequently washed thoroughly with distilled water and oven dried at 105 0C for 1 h. These modified fibres were incorporated as composite into polyurethane form and used in dye adsorption study of indigo. The first two treatments led to fiber weight reduction, while the acidified acetic anhydride treatment gave the fibers weight increment. All the treated fibers were found to be of less hydrophilic nature, better mechanical properties, higher thermal stabilities as well as better adsorption surfaces/capacities than the untreated ones. These were confirmed by gravimetric analysis, Instron Universal Testing Machine, Thermogravimetric Analyser and the Scanning Electron Microscope (SEM) respectively. The fiber morphology of the modified fibers showed smoother surfaces than unmodified fibres.The empty fruit bunch fibre and the coconut coir fibre are better than the palm kernel fibres as reinforcers for composites or as adsorbents for waste-water treatment. Acetylation and alkaline bleaching treatment improve the potentials of the fibres more than mercerization treatment. Conclusively, vegetable fibres, especially empty fruit bunch fibre and the coconut coir fibre, which are cheap, abundant and underutilized, can replace the very costly powdered activated carbon in wastewater treatment and as reinforcer in foam.

Keywords: chemical modification, industrial application, value addition, vegetable fibre

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Authors: Sodamade Abiodun, Adeboye Olubunmi Omolara

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Problems associated with protein malnutrition are still prevalent in third-world countries, leading to the constant search for plants that can serve as nutrients and medicinal purposes. Huckleberry is one of the plants that has been proven useful locally in the treatment of numerous ailments and diseases. A fresh sample of Huckleberry was collected from a vegetable garden situated near the Erelu dam of the Emmanuel Alayande College of Education campus, Oyo. The sample was authenticated at the forestry research institute of Nigeria (FRIN) Ibadan. The leaves of the plant were plucked and processed for leaf protein concentrates before proximate composition; mineral analysis phytochemical and antimicrobial properties of the leaf protein concentrates were determined using a standard method of analysis. The results of proximate constituents showed; moisture content; 9.89±0.051g/100g, Ash; 3.23±0.12g/100g, crude fat; 3.96±0.11g/100g and 61.27±0.56g/100g of Nitrogen free extractive results of the mineral analysis showed that the sample contains Mg; 0.081±0.00mg/100g, Ca; 42.30±0.05mg/100g, Na; 27.57±0.09mg/100g, K; 6.81±0.01mg/100g, P; 8.90±0.03mg/100g Fe; 0.51±0.00mg/100g, Zn; 0.021±0.00mg/100g, Cd; 0.04±0.04mg/100g, Pb; 0.002±0.00mg/100g, Cr; 0.041±0.00mg/100g while cadmium was not detected in the sample. The result of phytochemical analysis of leaf protein concentrates of the Huckleberry showed the presence of Alkaloid, Saponin, Flavonoid, Tanin, Coumarin, steroid, Terpenoid, cordial glycosides, Glycosides, Quinones, Anthocyanin, phytosterols, and phenols. Ethanolic extracts of the Huckleberry leaf protein concentrates showed that it contains bioactive compounds that are capable of eradicating some tested microorganisms; Staphylococcus aureus, Streptococcus pyogenes, Streptococcus faecalis, Pseudomonas aeruginosa, Klebisidlae pneumonia and Proteus merabilis. The results of the analysis of leaf protein concentrates of Huckleberry showed that the sample contains high nutrient and mineral constituents and phytochemical compounds that could make the sample useful for medicinal activities.

Keywords: huckleberry, mentha piperita, phytochemical, leaf protein concentrates, nutritional characteristics

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Authors: Raouf Ahmed Mohamed Hassan

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In Egypt, the excess sewage sludge from wastewater Treatment Plants (WWTPs) is rapidly increasing due to the continuous increase of population, urban planning and industrial developments. Also, cane bagasses constitute an important component of Urban Solid Waste (USW), especially at the south of Egypt, which are difficult to degrade under normal composting conditions. These wastes need to be environmentally managed to reduce the negative impacts of its application or disposal. In term of biogas recovery, the anaerobic digestion of sewage sludge or bagasse separately is inefficient, due to the presence of nutrients and minerals. Also, the Carbone-Nitrogen Ratio (C/N) play an important role, sewage sludge has a ratio varies from 6-16, where cane bagasse has a ratio around 150, whereas the suggested optimum C/N ratio for anaerobic digestion is in the range of 20 to 30. The anaerobic co-digestion is presented as a successful methodology that combines several biodegradable organic substrates able to decrease the amount of output wastes by biodegradation, sharing processing facilities, reducing operating costs, while enabling recovery of biogas. This paper presents the study of co-digestion of sewage sludge from wastewater treatment plants as a type of organic wastes and bagasse as agriculture wastes. Laboratory-scale mesophilic and thermophilic digesters were operated with varied hydraulic retention times. Different percentage of sludge and bagasse are investigated based on the total solids (TS). Before digestion, the bagasse was subjected to grinding pretreatment and soaked in distilled water (water pretreatment). The effect of operating parameters (mixing, temperature) is investigated in order to optimize the process in the biogas production. The yield and the composition of biogas from the different experiments were evaluated and the cumulative curves were estimated. The conducted tests did show that there is a good potential to using the co-digestion of wastewater sludge and bagasse for biogas production.

Keywords: co-digestion, sewage sludge, bagasse, mixing, mesophilic, thermophilic

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Authors: Mohammad Taghi Karbalaei Aghamolki, Mohd Khanif Yusop, Fateh Chand Oad, Hamed Zakikhani, Hawa Zee Jaafar, Sharifh Kharidah, Mohamed Hanafi Musa, Shahram Soltani

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The high temperatures during sensitive growth phases are changing rice morphology as well as influencing yield. In the glass house study, the treatments were: growing conditions [normal growing (32oC+2) and heat stress (38oC+2) day time and 22oC+2 night time], growth stages (booting, flowering and ripening) and four cultivars (Hovaze, Hashemi, Fajr, as exotic and MR219 as indigenous). The heat chamber was prepared covered with plastic, and automatic heater was adjusted at 38oC+2 (day) and 22oC+2 (night) for two weeks in every growth stages. Rice morphological and yield under the influence of heat stress during various growth stages showed taller plants in Hashsemi due to its tall character. The total tillers per hill were significantly higher in Fajr receiving heat stress during booting stage. In all growing conditions and growth stages, Hashemi recorded higher panicle exertion and flag leaf length. The flag leaf width in all situations was found higher in Hovaze. The total tillers per hill were more in Fajr, although heat stress was imposed during booting and flowering stages. The indigenous MR219 in all situations of growing conditions, growth stages recorded higher grain yield. However, its grain yield slightly decreased when heat stress was imposed during booting and flowering. Similar results were found in all other exotic cultivars recording to lower grain yield in the heat stress condition during booting and flowering. However, plants had no effect on heat stress during ripening stage.

Keywords: rice, growth, heat, temperature, stress, morphology, yield

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Authors: Yi-Yu Huang, Chien-Kuo Wang, Sreerag Chota Veettil, Hang Zhang, Hu Yike

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Regarding the pressing issue of reducing energy consumption and carbon footprint of buildings, past research has focused more on analyzing the thermal performance of the extensive terrestrial green roofs with sedum plants in summer. However, the disadvantages of this type of green roof are relatively limited thermal performance, low extreme weather adaptability, relatively higher demands in maintenance, and lower added value in healing landscape. In view of this, this research aims to develop the extensive wetland green roofs with higher thermal performance, high extreme weather adaptability, low demands in maintenance, and high added value in healing landscape, and to measure its thermal performance for buildings in winter. The following factors are considered including the type and mixing formula of growth medium (light weight soil, akadama, creek gravel, pure water) and the type of aquatic plants. The research adopts a four-stage field experiment conducting on the rooftop of a building in a humid subtropical climate. The results found that emergent (Roundleaf rotala), submerged (Ribbon weed), floating-leaved (Water lily) wetland green roofs had similar thermal performance, and superior over wetland green roof without plant, traditional terrestrial green roof (without plant), and pure water green roof (without plant, nighttime only) in terms of overall passive cooling (8.00C) and thermal insulation (4.50C) effects as well as a reduction in heat amplitude (77-85%) in winter in a humid subtropical climate. The thermal performance of the free-floating (Water hyacinth) wetland green roof is inferior to that of the other three types of wetland green roofs, whether in daytime or nighttime.

Keywords: thermal performance, extensive wetland green roof, Aquatic plant, Winter , Humid subtropical climate

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Authors: M. F. El-Barghathi, R. El-Tajouri

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The effect of different concentrations of cadmium sulfate "CdSO4" (0.0, 10, 50, 100, 500 ppm) was tested on seed germination, seedling elongation and growth of Lepidium sativum (garden cress) plants. Results indicated that seed germination and seedling elongation were not inhibited by different concentrations of CdSO4. This could suggest that, Lepidium sativum may be used as a phyto remediation tool of soils contaminated with cadmium.

Keywords: Lepidium sativum, heavy metals, ionic toxicity, phytoremediation

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Authors: H. M. Zakir Hossain

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Cenozoic mudstone samples, obtained from drilled cored and outcrop in northeastern Bengal Basin of Bangladesh were organic geochemically analyzed to identify vertical variations of organic facies, thermal maturity, hydrocarbon potential and depositional environments. Total organic carbon (TOC) content ranges from 0.11 to 1.56 wt% with an average of 0.43 wt%, indicating a good source rock potential. Total sulphur content is variable with values ranging from ~0.001 to 1.75 wt% with an average of 0.065 wt%. Rock-Eval S1 and S2 yields range from 0.03 to 0.14 mg HC/g rock and 0.01 to 0.66 mg HC/g rock, respectively. The hydrogen index values range from 2.71 to 56.09 mg HC/g TOC. These results revealed that the samples are dominated by type III kerogene. Tmax values of 426 to 453 °C and vitrinite reflectance of 0.51 to 0.66% indicate the organic matter is immature to mature. Saturated hydrocarbon ratios such as pristane, phytane, steranes, and hopanes, indicate mostly terrigenous organic matter with small influence of marine organic matter. Organic matter in the succession was accumulated in three different environmental conditions based on the integration of biomarker proxies. First phase (late Eocene to early Miocene): Deposition occurred entirely in seawater-dominated oxic conditions, with high inputs of land plants organic matter including angiosperms. Second phase (middle to late Miocene): Deposition occurred in freshwater-dominated anoxic conditions, with phytoplanktonic organic matter and a small influence of land plants. Third phase (late Miocene to Pleistocene): Deposition occurred in oxygen-poor freshwater conditions, with abundant input of planktonic organic matter and high influx of angiosperms. The lower part (middle Eocene to early Miocene) of the succession with moderate TOC contents and primarily terrestrial organic matter could have generated some condensates and oils in and around the study area.

Keywords: Bangladesh, geochemistry, hydrocarbon potential, mudstone

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Authors: Seyed Mahdi Rafiaei

Abstract:

In this investigation, red emitting Eu³⁺ doped YVO₄ nano-phosphors have been synthesized via the facile combustion method using isobutyl nitrite and urea fuels, individually. Field-emission scanning electron microscope (FE-SEM) images, high resolution transmission electron microscope (TEM) images and X-ray diffraction (XRD) spectra reveal that the mentioned fuels can be used successfully to synthesis YVO₄: Eu³⁺ nano-particles. Interestingly, the fuels have a large effect on the size and morphology of nano-phosphors as well as luminescence properties. Noteworthy the use of isobutyl nitrite provides an average particle size of 65 nm, while the employment of urea, results in the formation of larger particles and also provides higher photoluminescence emission intensity. The improved luminescence performance is attributed to the condition of chemical reaction via the combustion synthesis and the size of synthesized phosphors.

Keywords: phosphors, combustion, fuels, luminescence, nanostructure

Procedia PDF Downloads 138