Search results for: yield increase

Authors: Alcino Panguana

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All Portuguese-speaking African countries are in Sub-Saharan Africa, a region that has high infant mortality rates, being responsible for 49.6% of deaths in Portuguese-speaking African countries, Angola has levels of infant mortality among children, where 2017, 156 children who died before reaching 1 year of life in 1000 live births. Although there is an increase in studies that document trends and specific causes of infant mortality in each country, historical-comparative studies of infant mortality among these countries remain rare. Understanding the trend of this indicator is important for policymakers and planners in order to improve access to successful child survival operations. Lusophone Africa continues with high infant mortality rates in the order of 64 deaths per thousand births. Assuming heterogeneities that can characterize these countries, raise an analysis investigated indicator at the country level to understand the pattern and historical trend of infant mortality within Lusophone Africa from the year 2021. The result is to understand the levels and evolution of infant mortality in Portuguese-speaking African countries.

Keywords: child mortality, levels, trends, lusophone African countries

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Authors: Xianbao Sun, Jinlong Zhao, Shudong He, Jing Li

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Volutharpa ampullacea perryi is a high-protein marine shellfish. However, few data are available on the effects of boiling temperatures and time on quality of the meat. In this study, colour, texture and sensory characteristics of Volutharpa ampullacea perryi meat during the boiling cooking processes (75-100 °C, 5-60 min) were investigated by colors analysis, texture profile analysis (TPA), scanning electron microscope (SEM) and sensory evaluation. The ratio of cooking loss gradually increased with the increase of temperature and time. The colour of meat became lighter and more yellower from 85 °C to 95 °C in a short time (5-20 min), but it became brown after a 30 min treatment. TPA results showed that the Volutharpa ampullacea perryi meat were more firm and less cohesive after a higher temperature (95-100 °C) treatment even in a short period (5-15 min). Based on the SEM analysis, it was easily found that the myofibrils structure was destroyed at a higher temperature (85-100 °C). Sensory data revealed that the meat cooked at 85-90 °C in 10-20 min showed higher scores in overall acceptance, as well as color, hardness and taste. Based on these results, it could be constructed that Volutharpa ampullacea perryi meat should be heated on a suitable condition (such as 85 °C 15 min or 90 °C 10 min) in the boiling cooking to be ensure a better acceptability.

Keywords: Volutharpa ampullacea perryi meat, boiling cooking, colour, sensory, texture

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Authors: Jeremy Moloney

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A major oil and gas operator in western Canada producing approximately 50,000 BOE per day of sour fluids was experiencing increased water production along with decreased oil production over several years. The higher water volumes being produced meant an increase in the operator’s incumbent corrosion inhibitor (CI) chemical requirements but with reduced oil production revenues. Thus, a cost-effective corrosion inhibitor solution was sought to deliver enhanced corrosion mitigation of the carbon steel pipeline infrastructure but at reduced chemical injection dose rates. This paper presents the laboratory work conducted on the development of a corrosion inhibitor under the operator’s simulated sour operating conditions and then subsequent field testing of the product. The new CI not only provided extremely good levels of general and localized corrosion inhibition and outperformed the incumbent CI under the laboratory test conditions but did so at vastly lower concentrations. In turn, the novel CI product facilitated field chemical injection rates to be optimized and reduced by 40% compared with the incumbent whilst maintaining superior corrosion protection resulting in significant cost savings and associated sustainability benefits for the operator.

Keywords: carbon steel, sour gas, hydrogen sulphide, localized corrosion, pitting, corrosion inhibitor

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Authors: M. M. Alsharif

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4-Nonylphenol Compound is widely used as an element of detergents, paints, insecticides and many others products. It is known that the existence of this compound may lead to the emission of estrogenic responses in mammals, birds and fish. It is described as pollutant since it causes disorder of endocrine glands. In previous studies, it was proven that this compound exists in water and in the materials precipitated in Red Sea coast in Jeddah near the drains of processed drainage water and near the drainage site of the residuals of paper factories. Therefore, this study aimed to evaluate the cytogenetic aberrations caused by 4-nonylphenol through exposing Talapia Fishes to aquatic solution of the compound with 0, 15, 30 microgram/liter for one month. Samples of gills and liver were collected for micronuclei, nuclear abnormalities and measuring DNA and RNA amount in the treated fish. The results pointed out that there is a significant increase in the numbers of micronuclei in the fish exposed to the former concentrations as compared to the control group. Exposing fishes to 4-nonylphenol resulted in an increased amount of both DNA and RNA, compared to the control group. There is a positive correlation between the amount of the compound (i.e. dosage dependent effect) and the inspiring for cytogenetic effect on Talapia fishes in Jeddah. Therefore, micronucleus test, DNA and RNA contents can be considered as an index of cumulative exposure, which appear to be a sensitive model to evaluate genotoxic effects of 4-Nonylphenol compound on fish.

Keywords: genotoxic, 4-nonylphenol, micronuclei, fish, DNA, RNA

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Authors: Sujeeta Karki, Jeeban Poudel, Ja Hyung Choi, Sea Cheon Oh

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A lab-scale fluidized bed was used for the study of sewage sludge, a non-lignocellulosic biomass, torrefaction. The influence of torrefaction temperature ranging from 200–350 °C and residence time of 0–50 minutes on the physical and chemical properties of the torrefied product was investigated. Properties of the torrefied product were analyzed on the basis of degree of torrefaction, ultimate and proximate analysis, gas analysis and chemical exergy. The degree of torrefaction and chemical exergy had a positive influence on increasing the torrefaction temperature. Moreover, the effect of torrefaction temperature and residence time on the elemental variation of sewage sludge exhibited an increase in the weight percentage of carbon while the content of H/C and O/C molar ratios decreased. The product gas emitted during torrefaction was analyzed to study the pathway of hydrocarbons and oxygen-containing compounds. The compounds with oxygen were emitted at higher temperatures in contrast to hydrocarbon gases. An attempt was made to obtain the chemical exergy of sewage sludge. In addition, the study of various correlations for predicting the calorific value of torrefied sewage sludge was made.

Keywords: chemical exergy, degree of torrefaction, fluidized bed, higher heating value (HHV), O/C and H/C molar ratios, sewage sludge

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Authors: Chevonne Reynolds, Res Altwegg, Andrew Balmford, Claire N. Spottiswoode

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Modern agriculture has revolutionised the planet’s capacity to support humans, yet has simultaneously had a greater negative impact on biodiversity than any other human activity. Balancing the demand for food with the conservation of biodiversity is one of the most pressing issues of our time. Biodiversity-friendly farming (‘land sharing’), or alternatively, separation of conservation and production activities (‘land sparing’), are proposed as two strategies for mediating the trade-off between agriculture and biodiversity. However, there is much debate regarding the efficacy of each strategy, as this trade-off has typically been addressed by short term studies at fine spatial scales. These studies ignore processes that are relevant to biodiversity at larger scales, such as meta-population dynamics and landscape connectivity. Therefore, to better understand species response to agricultural land-use and provide evidence to underpin the planning of better production landscapes, we need to determine the merits of each strategy at larger scales. In South Africa, a remarkable citizen science project - the South African Bird Atlas Project 2 (SABAP2) – collates an extensive dataset describing the occurrence of birds at a 5-min by 5-min grid cell resolution. We use these data, along with fine-resolution data on agricultural land-use, to determine which strategy optimises the agriculture-biodiversity trade-off in a southern African context, and at a spatial scale never considered before. To empirically test this trade-off, we model bird species population density, derived for each 5-min grid cell by Royle-Nicols single-species occupancy modelling, against both the amount and configuration of different types of agricultural production in the same 5-min grid cell. In using both production amount and configuration, we can show not only how species population densities react to changes in yield, but also describe the production landscape patterns most conducive to conservation. Furthermore, the extent of both the SABAP2 and land-cover datasets allows us to test this trade-off across multiple regions to determine if bird populations respond in a consistent way and whether results can be extrapolated to other landscapes. We tested the land sparing/sharing trade-off for 281 bird species across three different biomes in South Africa. Overall, a higher proportion of species are classified as losers, and would benefit from land sparing. However, this proportion of loser-sparers is not consistent and varies across biomes and the different types of agricultural production. This is most likely because of differences in the intensity of agricultural land-use and the interactions between the differing types of natural vegetation and agriculture. Interestingly, we observe a higher number of species that benefit from agriculture than anticipated, suggesting that agriculture is a legitimate resource for certain bird species. Our results support those seen at smaller scales and across vastly different agricultural systems, that land sparing benefits the most species. However, our analysis suggests that land sparing needs to be implemented at spatial scales much larger than previously considered. Species persistence in agricultural landscapes will require the conservation of large tracts of land, and is an important consideration in developing countries, which are undergoing rapid agricultural development.

Keywords: agriculture, birds, land sharing, land sparing

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Authors: Leonard Maaya, Michel Meulders, Martina Vandebroek

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Discrete Choice Experiments (DCE) are used to investigate how product attributes affect decision-makers’ choices. In DCEs, choice situations consisting of several alternatives are presented from which choice-makers select the preferred alternative. Standard multinomial logit models based on random utility theory can be used to estimate the utilities for the attributes. The overarching principle in these models is that respondents understand and use all the attributes when making choices. However, studies suggest that respondents sometimes ignore some attributes (commonly referred to as Attribute Non-Attendance/ANA). The choice modeling literature presents ANA as a static process, i.e., respondents’ ANA behavior does not change throughout the experiment. However, respondents may ignore attributes due to changing factors like availability of information on attributes, learning/fatigue in experiments, etc. We develop a dynamic mixture latent Markov model to model changes in ANA when information on attributes is provided. The model is illustrated on e-consumers’ webshop choices. The results indicate that the dynamic ANA model describes the behavioral changes better than modeling the impact of information using changes in parameters. Further, we find that providing information on attributes leads to an increase in the attendance probabilities for the investigated attributes.

Keywords: choice models, discrete choice experiments, dynamic models, e-commerce, statistical modeling

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Authors: Yu-Chen Wei, Dan-Leng Wang

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This study examines whether the reputation from media press affect the financial performance and market abnormal returns around the announcement of corporate social responsibility (CSR) award in the Taiwan Stock Market. The differences between this study and prior literatures are that the media reputation of media coverage and net optimism are constructed by using content analyses. The empirical results show the corporation which won CSR awards could promote financial performance next year. The media coverage and net optimism related to CSR winner are higher than the non-CSR companies prior and after the CSR award is announced, and the differences are significant, but the difference would decrease when the day was closing to announcement. We propose that non-CSR companies may try to manipulate media press to increase the coverage and positive image received by investors compared to the CSR winners. The cumulative real returns and abnormal returns of CSR winners did not significantly higher than the non-CSR samples however the leading returns of CSR winners would higher after the award announcement two months. The comparisons of performances between CSR and non-CSR companies could be the consideration of portfolio management for mutual funds and investors.

Keywords: corporate social responsibility, financial performance, abnormal returns, media, reputation management

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Authors: Mariela Edith Arboit

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The main goal of the project is to explore the evolution possibilities of the morphological indicators of the built environment, including those resulting from progressive soil occupation, due to the relentless growth of the city’s population and subsequent increase in building density and solar access reduction per built unit. Two alternative normative proposals, Conventional Proposal (CP) and Alternative Proposal (AP), are compared. In addition, temporal scenarios of the city’s evolution process are analyzed, starting from the reference situation of existing, high-density built-up areas, and simulating their possible morphological outcomes on theoretical medium (30 yr.) and long (60 yr.) terms, as a result of the massive implementation of either regulation in the long run. The results obtained demonstrate that the Alternative Proposal (AP) presents higher mean values of predicted solar potential expressed by the Volumetric Insolation Factor total (VIFtot) for both time periods and services. Regarding environmental aspects, the different impacts of either alternative on the urban landscape quality seem to favor the AP proposal. Its deserved detailed assessment is also presently being developed through a quanti-qualitative methodology.

Keywords: building morphology, environmental quality, solar energy, urban sustainability

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Authors: Loreta Serniene, Dalia Sekmokiene, Justina Tomkeviciute, Lina Lauciene, Vaida Andruleviciute, Ingrida Sinkeviciene, Kristina Kondrotiene, Neringa Kasetiene, Mindaugas Malakauskas

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One of the most important areas of product development and research in the dairy industry is the product enrichment with active ingredients as well as leading to increased product safety and sustainability. The most expanding field of the active ingredients is the various plants' CO₂ extracts with aromatic, antioxidant and antimicrobial properties. In this study, 15 plant extracts were evaluated based on their antioxidant, antimicrobial properties as well as sensory acceptance indicators for the development of new dairy products. In order to increase the total antioxidant capacity of the milk products, it was important to determine the content of phenolic compounds and antioxidant activity of CO₂ extract. The total phenolic content of fifteen different commercial CO₂ extracts was determined by the Folin-Ciocalteu reagent and expressed as milligrams of the Gallic acid equivalents (GAE) in gram of extract. The antioxidant activities were determined by 2.2′-azinobis-(3-ethylbenzthiazoline)-6-sulfonate (ABTS) methods. The study revealed that the antioxidant activities of investigated CO₂ extract vary from 4.478-62.035 µmole Trolox/g, while the total phenolic content was in the range of 2.021-38.906 mg GAE/g of extract. For the example, the estimated antioxidant activity of Chinese cinnamon (Cinammonum aromaticum) CO₂ extract was 62.023 ± 0.15 µmole Trolox/g and the total flavonoid content reached 17.962 ± 0.35 mg GAE/g. These two parameters suggest that cinnamon could be a promising supplement for the development of new cheese. The inhibitory effects of these essential oils were tested by using agar disc diffusion method against pathogenic bacteria, most commonly found in dairy products. The obtained results showed that essential oil of lemon myrtle (Backhousia citriodora) and cinnamon (Cinnamomum cassia) has antimicrobial activity against E. coli, S. aureus, B. cereus, P. florescens, L. monocytogenes, Br. thermosphacta, P. aeruginosa and S. typhimurium with the diameter of inhibition zones variation from 10 to 52 mm. The sensory taste acceptability of plant extracts in combination with a dairy product was evaluated by a group of sensory evaluation experts (31 individuals) by the criteria of overall taste acceptability in the scale of 0 (not acceptable) to 10 (very acceptable). Each of the tested samples included 200g grams of natural unsweetened greek yogurt without additives and 1 drop of single plant extract (essential oil). The highest average of overall taste acceptability was defined for the samples with essential oils of orange (Citrus sinensis) - average score 6.67, lemon myrtle (Backhousia citriodora) – 6.62, elderberry flower (Sambucus nigra flos.) – 6.61, lemon (Citrus limon) – 5.75 and cinnamon (Cinnamomum cassia) – 5.41, respectively. The results of this study indicate plant extracts of Cinnamomum cassia and Backhousia citriodora as a promising additive not only to increase the total antioxidant capacity of the milk products and as alternative antibacterial agent to combat pathogenic bacteria commonly found in dairy products but also as a desirable flavour for the taste pallet of the consumers with expressed need for safe, sustainable and innovative dairy products. Acknowledgment: This research was funded by the European Regional Development Fund according to the supported activity 'Research Projects Implemented by World-class Researcher Groups' under Measure No. 01.2.2-LMT-K-718.

Keywords: antioxidant properties, antimicrobial properties, cinnamon, CO₂ plant extracts, dairy products, essential oils, lemon myrtle

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Authors: Simisola I. Akintoye, Sunday K. Iyaniwura

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Recent global corporate failures have called for increase in the need to regulate corporate governance across the world. In Nigeria, the impact of corporate governance regulation in the banking sector has reached epidemic levels contributing to the country’s economic depression. This study critically evaluates Nigeria’s corporate governance regime and explores how weak regulation has impacted on the banking sector. By adopting a socio legal methodology, the study analyses both theoretical and empirical works from a socio-scientific point of view to examine the role of Nigeria’s legal, cultural and social arrangements in corporate governance regulation. The study reveals that Nigeria’s institutional arrangement has contributed to its weak system of corporate governance regulation with adverse effects on the banking sector. The research mainly impacts on current global corporate governance literature in sub-Saharan Africa by contributing to knowledge of the peculiarities of corporate governance regulation in different institutional jurisdictions. The particular focus on emerging economies such as Nigeria expands on the need for countries to develop a bespoke system of corporate governance regulation that takes into consideration the peculiarities of individual countries devoid of external influence.

Keywords: banks, corporate governance, emerging economies, Nigeria

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Authors: Tismazammi Mustafa, Jaharudin Padli

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The frequency of terrorism is increasing throughout years that is resulting in loss of life, damaging people’s property, and destructing the environment. The incident of terrorism is not stationed in one particular country but has spread and scattered in other countries hence causing an increase in the number of terrorism cases. Thus, this paper aims to investigate the factors of human development upon the terrorism in East Asia and Pacific countries. This study used a panel ARDL model, in which it enables to capture the long run and the short run relationship among the variables of interest. Logit Model for Binary data is also used, in which to representing an attributes of dependent variables. This study focuses on several human development variables namely GDP per capita, population, human capital, land area, and technologies. The empirical finding revealed that the GDP per capita, population, human capital, land area, and technologies are positively and statistically significant in influencing the terrorism. Thus, the finding in this study will present as grounds to preserve human rights and develop public awareness and will offer guidelines to policy makers, emergency managers, first responders, public health workers, physicians, and other researchers.

Keywords: terrorism, East Asia and Pacific, human development, econometric analysis

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Authors: Asma'u Mahe, Abdullahi A. Imam, Adamu J. Alhassan, Nasiru Abdullahi, Sadiya A. Bichi, Nura Lawal, Kamaluddeen Babagana

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Malaria is a disease with global health significance. It is caused by parasites and transmitted by Anopheles mosquitoes. Increase in insecticide resistance threatens the disease vector control. The strength of selection pressure acting on a mosquito population in relation to insecticide resistance can be assess by determining the genetic diversity of a fragment spanning exon- 20 of IIS6 of the voltage gated sodium channel (VGSC). Larval samples reared to adulthood were identified and kdr (knock down resistance) profile was determined. The DNA sequences were used to assess the patterns of genetic differentiation by determining the levels of genetic variability between the Anopheles mosquitoes. Genetic differentiation of the Anopheles mosquitoes based on a portion of the voltage gated sodium channel gene was obtained. Polymorphisms were detected; sequence variation and analysis were presented as a phylogenetic tree. Phylogenetic tree of VGSC haplotypes was constructed for samples of the Anopheles mosquitoes using the maximum likelihood method in MEGA 6.0 software. DNA sequences were edited using BioEdit sequence editor. The edited sequences were aligned with reference sequence (Kisumu strain). Analyses were performed as contained in dnaSP 5.10. Results of genetic parameters of polymorphism and haplotype reconstruction were presented in count. Twenty sequences were used for the analysis. Regions selected were 1- 576, invariable (monomorphic) sites were 460 while variable (polymorphic) sites were 5 giving the number of total mutations observed in this study. Mutations obtained from the study were at codon 105: TTC- Phenylalanine replaces TCC- Serine, codon 513: TAG- Termination replaces TTG- Leucine, codon 153, 300 and 553 mutations were non-synonymous. From the constructed phylogenetic tree, some groups were shown to be closer with Exon20Gambiae Kisumu (Reference strain) having some genetic distance, while 5-Exon20Gambiae-F I13.ab1, 18-Exon20Gambiae-F C17.ab1, and 2-Exon20Gambiae-F C13.ab1 clustered together genetically differentiated away from others. Mutations observed in this study can be attributed to the high insecticide resistance profile recorded in the study areas. Haplotype networks of pattern of genetic variability and polymorphism for the fragment of the VGSC sequences of sampled Anopheles mosquitoes revealed low haplotypes for the present study. Haplotypes are set of closely linked DNA variation on X-chromosome. Haplotypes were scaled accordingly to reflect their respective frequencies. Low haplotype number, four VGSC-1014F haplotypes were observed in this study. A positive association was previously established between low haplotype number of VGSC diversity and pyrethroid resistance through kdr mechanism. Significant values at (P < 0.05) of Tajima D and Fu and Li D’ were observed for some of the results indicating possible signature of positive selection on the fragment of VGSC in the study. This is the first report of VGSC-1014F in the study site. Based on the results, the mutation was present in low frequencies. However, the roles played by the observed mutations need further investigation. Mutations, environmental factors among others can affect genetic diversity. The study area has recorded increase in insecticide resistance that can affect vector control in the area. This finding might affect the efforts made against malaria. Sequences were deposited in GenBank for Accession Number.

Keywords: anopheles mosquitoes, insecticide resistance, kdr, malaria, voltage gated sodium channel

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Authors: Nisha Sharma, Mili Kaur, Ashutosh Halder, Seema Kaushal, Manoj Kumar, Manish Jain

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Purpose: To investigate microRNAs (miRNA) as an epigenomic etiological factor in idiopathic non-obstructive azoospermia (NOA). In order to achieve the same, an association was seen between occupational exposure to radiation, thermal, and chemical factors and idiopathic cases of non-obstructive azoospermia, and later, testicular differential miRNA expression profiling was done in exposure group NOA cases. Method: It is a prospective study in which 200 apparent idiopathic male factor infertility cases, who have been advised to undergo testicular fine needle aspiration (FNA) evaluation, are recruited. A detailed occupational history was taken to understand the possible type of exposure due to the nature and duration of work. A total of 26 patients were excluded upon XY-FISH and Yq microdeletion tests due to the presence of genetic causes of infertility, 6 hypospermatogeneis (HS), six Sertoli cell-only syndrome (SCOS), and six normospermatogeneis patients testicular FNA samples were used for RNA isolation followed by small RNA sequencing and nCounter miRNA expression analysis. Differential miRNA expression profile of HS and SCOS patients was done. A web-based tool, miRNet, was used to predict the interacting compounds or chemicals using the shortlisted miRNAs with high fold change. The major limitation encountered in this study was the insufficient quantity of testicular FNA sample used for total RNA isolation, which resulted in a low yield and RNA integrity number (RIN) value. Therefore, the number of RNA samples admissible for differential miRNA expression analysis was very small in comparison to the total number of patients recruited. Results: Differential expression analysis revealed 69 down-regulated and 40 up-regulated miRNAs in HS and 66 down-regulated and 33 up-regulated miRNAs in SCOS in comparison to normospermatogenesis controls. The miRNA interaction analysis using the miRNet tool showed that the differential expression profiles of HS and SCOS patients were associated with arsenic trioxide, bisphenol-A, calcium sulphate, lithium, and cadmium. These compounds are reproductive toxins and might be responsible for miRNA-mediated epigenetic deregulation leading to NOA. The association between occupational risk factor exposure and the non-exposure group of NOA patients was not statistically significant, with ꭓ2 (3, N= 178) = 6.70, p= 0.082. The association between individual exposure groups (radiation, thermal, and chemical) and various sub-types of NOA is also not significant, with ꭓ2 (9, N= 178) = 15.06, p= 0.089. Functional analysis of HS and SCOS patients' miRNA profiles revealed some important miR-family members in terms of male fertility. The miR-181 family plays a role in the differentiation of spermatogonia and spermatocytes, as well as the transcriptional regulation of haploid germ cells. The miR-34 family is expressed in spermatocytes and round spermatids and is involved in the regulation of SSCs differentiation. Conclusion: The reproductive toxins might adopt the miRNA-mediated mechanism of disease development in idiopathic cases of NOA. Chemical compound induced; miRNA-mediated epigenetic deregulation can give a future perspective on the etiopathogenesis of the disease.

Keywords: microRNA, non-obstructive azoospermia (NOA), occupational exposure, hypospermatogenesis (HS), Sertoli cell only syndrome (SCOS)

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Authors: Rajan Vohra, Ravinder Singh Sawhney, Kunwar Partap Singh

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Electrical charge transport through two basic strands thymine and adenine of DNA have been investigated and analyzed using the jellium model approach. The FFT-2D computations have been performed for semi-empirical Extended Huckel Theory using atomistic tool kit to contemplate the charge transport metrics like current and conductance. The envisaged data is further evaluated in terms of transmission spectrum, HOMO-LUMO Gap and number of electrons. We have scrutinized the behavior of the devices in the range of -2V to 2V for a step size of 0.2V. We observe that both thymine and adenine can act as molecular devices when sandwiched between two gold probes. A prominent observation is a drop in HLGs of adenine and thymine when working as a device as compared to their intrinsic values and this is comparative more visible in case of adenine. The current in the thymine based device exhibit linear increase with voltage in spite of having low conductance. Further, the broader transmission peaks represent the strong coupling of electrodes to the scattering molecule (thymine). Moreover, the observed current in case of thymine is almost 3-4 times than that of observed for adenine. The NDR effect has been perceived in case of adenine based device for higher bias voltages and can be utilized in various future electronics applications.

Keywords: adenine, DNA, extended Huckel, thymine, transmission spectra

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Authors: Natalia C. E. S. Nascimento, Mercia L. Oliveira, Fernando R. A. Lima, Leonardo T. C. do Nascimento, Marina B. Silveira, Brigida G. A. Schirmer, Andrea V. Ferreira, Carlos Malamut, Juliana B. da Silva

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Tissue hypoxia is a common characteristic of solid tumors leading to decreased sensitivity to radiotherapy and chemotherapy. In the clinical context, tumor hypoxia assessment employing the positron emission tomography (PET) tracer ¹⁸F-fluoromisonidazole ([¹⁸F]FMISO) is helpful for physicians for planning and therapy adjusting. The aim of this work was to implement the synthesis of 18F-FMISO in a TRACERlab® MXFDG module and also to establish the quality control procedure. [¹⁸F]FMISO was synthesized at Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN/Brazil) using an automated synthesizer (TRACERlab® MXFDG, GE) adapted for the production of [¹⁸F]FMISO. The FMISO chemical standard was purchased from ABX. 18O- enriched water was acquired from Center of Molecular Research. Reagent kits containing eluent solution, acetonitrile, ethanol, 2.0 M HCl solution, buffer solution, water for injections and [¹⁸F]FMISO precursor (dissolved in 2 ml acetonitrile) were purchased from ABX. The [¹⁸F]FMISO samples were purified by Solid Phase Extraction method. The quality requirements of [¹⁸F]FMISO are established in the European Pharmacopeia. According to that reference, quality control of [¹⁸F]FMISO should include appearance, pH, radionuclidic identity and purity, radiochemical identity and purity, chemical purity, residual solvents, bacterial endotoxins, and sterility. The duration of the synthesis process was 53 min, with radiochemical yield of (37.00 ± 0.01) % and the specific activity was more than 70 GBq/µmol. The syntheses were reproducible and showed satisfactory results. In relation to the quality control analysis, the samples were clear and colorless at pH 6.0. The spectrum emission, measured by using a High-Purity Germanium Detector (HPGe), presented a single peak at 511 keV and the half-life, determined by the decay method in an activimeter, was (111.0 ± 0.5) min, indicating no presence of radioactive contaminants, besides the desirable radionuclide (¹⁸F). The samples showed concentration of tetrabutylammonium (TBA) < 50μg/mL, assessed by visual comparison to TBA standard applied in the same thin layer chromatographic plate. Radiochemical purity was determined by high performance liquid chromatography (HPLC) and the results were 100%. Regarding the residual solvents tested, ethanol and acetonitrile presented concentration lower than 10% and 0.04%, respectively. Healthy female mice were injected via lateral tail vein with [¹⁸F]FMISO, microPET imaging studies (15 min) were performed after 2 h post injection (p.i), and the biodistribution was analyzed in five-time points (30, 60, 90, 120 and 180 min) after injection. Subsequently, organs/tissues were assayed for radioactivity with a gamma counter. All parameters of quality control test were in agreement to quality criteria confirming that [¹⁸F]FMISO was suitable for use in non-clinical and clinical trials, following the legal requirements for the production of new radiopharmaceuticals in Brazil.

Keywords: automatic radiosynthesis, hypoxic tumors, pharmacopeia, positron emitters, quality requirements

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Authors: Suprabha Islam, Sifat Ullah Tanzil

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During past few decades, being amazed by the excellent silent flight of owl, scientists have been trying to demystify the unique features of its wing feathers. Our present study is dedicated to taking our understanding further on this phenomenon. In this present study, a numerical investigation was performed to analyze how the shape of the leading-edge serration at owl wing feathers effects the flow-induced noise generation. For the analysis, an owl inspired single feather wing model was prepared for both with and without serrations at the leading edge. The serration profiles were taken at different positions of the vane length for a single feather. The broadband noise was studied to quantify the local contribution to the total acoustic power generated by the flow, where the results clearly showed the effect of serrations in reducing the noise generation. It was also clearly visible that the shape of the serration has a very strong influence on noise generation. The frequency spectrum of noise was also analyzed and a strong relation was found between the shape of the serration and the noise generation. It showed that the noise suppression is strongly influenced by the height to length ratio of the serration. With the increase in height to length ratio, the noise suppression is enhanced further.

Keywords: aeroacoustics, aerodynamic, biomimetics, serrations

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Authors: Marianna I. Triantou, Petroula A. Tarantili

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In this research work, poly (acrylonitrile-butadiene-styrene)/polypropylene (ABS/PP) blends were processed by melt compounding in a twin-screw extruder. Upgrading of the thermal characteristics of the obtained materials was attempted by the incorporation of organically modified montmorillonite (OMMT), as well as, by the addition of two types of compatibilizers; polypropylene grafted with maleic anhydride (PP-g-MAH) and ABS grafted with maleic anhydride (ABS-g-MAH). The effect of the above treatments was investigated separately and in combination. Increasing the PP content in ABS matrix seems to increase the thermal stability of their blend and the glass transition temperature (Tg) of SAN phase of ABS. From the other part, the addition of ABS to PP promotes the formation of its β-phase, which is maximum at 30 wt% ABS concentration, and increases the crystallization temperature (Tc) of PP. In addition, it increases the crystallization rate of PP.The β-phase of PP in ABS/PP blends is reduced by the addition of compatibilizers or/and organoclay reinforcement. The incorporation of compatibilizers increases the thermal stability of PP and reduces its melting (ΔΗm) and crystallization (ΔΗc) enthalpies. Furthermore it decreases slightly the Tgs of PP and SAN phases of ABS/PP blends. Regarding the storage modulus of the ABS/PP blends, it presents a change in their behavior at about 10°C and return to their initial behavior at ~110°C. The incorporation of OMMT to no compatibilized and compatibilized ABS/PP blends enhances their storage modulus.

Keywords: acrylonitrile, butadiene, styrene terpolymer, compatibilizer, organoclay, polypropylene

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Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana

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Key concepts like waste heat recycling or waste heat recovery are the basic ideas in thermoelectricity so as to the design the newest solid state sources of energy for a stable supply of electricity and environmental protection. According to several theoretical predictions; at device level, the geometry and configuration of the thermoelectric legs are crucial in the thermoelectric performance of the thermoelectric modules. Thus, in this work, it has studied the geometry effect of legs on the thermoelectric figure of merit ZT of the device. First, asymmetrical legs are proposed in order to reduce the overall thermal conductance of the device so as to increase the temperature gradient in the legs, as well as by harnessing the Thomson effect, which is generally neglected in conventional symmetrical thermoelectric legs. It has been developed a novel design of a thermoelectric module having asymmetrical legs, and by first time it has been validated experimentally its thermoelectric performance by realizing a proof-of-concept device which shows to have almost twofold the thermoelectric figure of merit as compared to conventional one. Moreover, it has been also varied the length of thermoelectric legs in order to analyze its effect on the thermoelectric performance of the device. Along with this, it has studied the impact of contact resistance in these systems. Experimental results show that device architecture can improve up to twofold the thermoelectric performance of the device.

Keywords: asymmetrical legs, heat recovery, heat recycling, thermoelectric module, Thompson effect

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Authors: Virgil-Florin Duma, Dorin Demian

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Optical choppers are among the most common optomechatronic devices, utilized in numerous applications, from radiometry to telescopes and biomedical imaging. The classical configuration has a rotational disk with windows with linear margins. This research points out the laser signals that can be obtained with these classical choppers, as well as with another, novel, patented configuration, of eclipse choppers (i.e., with rotational disks with windows with non-linear margins, oriented outwards or inwards). Approximately triangular laser signals can be obtained with eclipse choppers, in contrast to the approximately sinusoidal – with classical devices. The main topic of this work refers to another, novel device, of choppers with shafts of different shapes and with slits of various profiles (patent pending). A significant improvement which can be obtained (with regard to disk choppers) refers to the chop frequencies of the laser signals. Thus, while 1 kHz is their typical limit for disk choppers, with choppers with shafts, a more than 20 times increase in the chop frequency can be obtained with choppers with shafts. Their transmission functions are also discussed, for different types of laser beams. Acknowledgments: This research is supported by the Romanian National Authority for Scientific Research, through the project PN-III-P2-2.1-BG-2016-0297.

Keywords: laser signals, laser systems, optical choppers, optomechatronics, transfer functions, eclipse choppers, choppers with shafts

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Authors: Xian-Peng Jiang, Catherine C. Baucom, Toby Jiang, Robert L. Elliott

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HLA-G binds to the inhibitory receptors of uterine NK cells and plays an important role in protection of fetal cells from maternal NK lysis. HLA-G also mediates tumor escape, but the immunosuppressive role is often neglected. These studies have focused on the examination of HLA-G expression in human breast carcinoma and HLA-G immunosuppressive role in NK cytolysis. We examined HLA-G expression in breast cell lines by real time PCR, ELISA and immunofluorescent staining. We treated the breast cancer cell lines with anti-human HLA-G antibody or progesterone. Then, NK cytolysis was measured by using MTT assay. We find that breast carcinoma cell lines increase the expression of HLA-G mRNA and protein, compared to normal cells. Blocking HLA-G of the breast cancer cells by the antibody increases NK cytolysis. Progesterone upregulates HLA-G mRNA and protein of human breast cancer cell lines. The increased HLA-G expression suppresses NK cytolysis. In summary, human breast carcinoma overexpress HLA-G immunosuppressive molecules. Blocking HLA-G protein by antibody improves NK cytolysis. In contrast, upregulation of HLA-G expression by progesterone impairs NK cytolytic function. Thus, HLA-G is a new immunosuppressive checkpoint and potential cancer immunotherapeutic target.

Keywords: HLA-G, Breast carcinoma, NK cells, Immunosuppressive checkpoint

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Authors: Dima Basma

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The unprecedented expansion in the use of Non-Fungible Tokens (NFTS) has prompted luxury brand owners to file their trademark applications for the use of their marks in the metaverse world. While NFTs provide a favorable tool for product traceability and anti-counterfeiting endeavors, the legal ramifications of such abrupt shift are complex, diverse, and yet to be understood. Practically, a sizable number of NFT creators are minting digital tokens associated with existing trademarks, selling them at strikingly high rates, thus disadvantaging trademark owners who joined and are yet to join the meta-verse world. As a result, multiple luxury brands are filing confusion and dilution lawsuits against alleged artists offering for sale NFTs depicting reputable marks labeling their use as “parody” and “social commentary.” Given the already muddled state of trademark law in relation to both traditional and modern infringement criteria, this paper aims to explore the feasibility of the current system in dealing with the emerging NFT trends. The paper firstly delves into the intersection between trademarks and NFTs. Furthermore, in light of the striking increase in NFT use, the paper sheds critical light on the shortcoming of the current system. Finally, the paper provides recommendations for overcoming current and prospective challenges in this area.

Keywords: trademarks, NFTs, dilution, social commentary

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Authors: Faduma Ahmed-Ali

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The up and coming new generation of travelers will change how the world will achieve its global connectivity. The goal is that through people and technological advancement world-wide, people will be able to better explore the culture and beauty, as well as gain a better understanding of the core values of each host countries treasures. Through Rika's unique world connection model approach, the tourist can explore their destination with the help of local connections. Achieving a complete understanding of the host country while ensuring equal economic prosperity and cultural exchange is key to changing the face of tourism. A recent survey conducted by the author at Portland International Airport shows that over 50% of tourists entering Portland, Oregon are more eager to explore the city through local residents rather than an already planned itinerary created by travel companies. This new model, Rika, aims to shed light to the importance of connecting tourists with the technological tools that increase connectivity to the locals for a better travel experience and that fosters shared economic prosperity throughout a community achieving the goal of creating a sustainable, people driven economy.

Keywords: RIKA, tourism, connection, technology, economic impact, sustainability, hospitality, strategies, tourism development, environment

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Authors: Thang Minh Le, Hadi Khabbaz

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The coefficient of consolidation is a parameter governing the rate at which saturated soil particularly clay undergoes consolidation when subjected to an increase in pressure. The rate and amount of compression in soil varies with the rate that pore water is lost; and hence depends on soil permeability. Over many years, various methods have been proposed to determine the coefficient of consolidation, cv, which is an indication of the rate of foundation settlement on soft ground. However, defining this parameter is often problematic and heavily relies on graphical techniques, which are subject to some uncertainties. This paper initially presents an overview of many well-established methods to determine the vertical coefficient of consolidation from the incremental loading consolidation tests. An array of consolidation tests was conducted on the undisturbed clay samples, collected at various depths from a site in Nakdong river delta, Busan, South Korea. The consolidation test results on these soft sensitive clay samples were employed to evaluate the targeted methods to predict the settlement rate of Busan clay. In relationship of time-displacement-velocity, a total of 3 method groups from 10 common procedures were classified and compared together. Discussions on study results will be also provided.

Keywords: Busan clay, coefficient of consolidation, constant rate of strain, incremental loading

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Authors: Afrah S. M. Al-Mahfadi

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Climate change is a global issue that has significant impacts on water resources, resulting in environmental, economic, and political consequences. Groundwater reserves, particularly in coastal areas, are facing depletion, leading to serious problems in regions such as Yemen. This study focuses on the western coastal region of Yemen, which already faces risks such as water crises, food insecurity, and widespread poverty. Climate change exacerbates these risks by causing high temperatures, sea level rise, inadequate sea level rise, and inadequate environmental policies. Research Aim: The aim of this research is to provide a comprehensive overview of the impact of climate change on the western coastal region of Yemen. Specifically, the study aims to analyze the relationship between climate change and the loss of fresh groundwater resources in this area. Methodology: The research utilizes a combination of a literature review and three case studies conducted through site visits. Arch-GIS mapping is employed to analyze and visualize the relationship between climate change and the depletion of fresh groundwater resources. Additionally, data on precipitation from 1981 to 2020 and scenarios of projected sea level rise (SLR) are considered. Findings: The study reveals several future issues resulting from climate change. It is projected that the annual temperature will increase while the rainfall rate will decrease. Furthermore, the sea level is expected to rise by approximately 0.30 to 0.72 meters by 2100. These factors contribute to the loss of wetlands, the retreat of shorelines and estuaries, and the intrusion of seawater into the coastal aquifer, rendering drinking water from wells increasingly saline. Data Collection and Analysis Procedures: Data for this research are collected through a literature review, including studies on climate change impacts in coastal areas and the hydrogeology of the study region. Furthermore, three case studies are conducted through site visits. Arch-GIS mapping techniques are utilized to analyze the relationship between climate change and the loss of fresh groundwater resources. Historical precipitation data from 1981 to 2020 and scenarios of projected sea level rise are also analyzed. Questions Addressed: (1) What is the impact of climate change on the western coastal region of Yemen? (2) How does climate change affect the availability of fresh groundwater resources in this area? Conclusion: The study concludes that the western coastal region of Yemen is facing significant challenges due to climate change. The projected increase in temperature, decrease in rainfall, and rise in sea levels have severe implications, such as the loss of wetlands, shorelines, and estuaries. Additionally, the intrusion of seawater into the coastal aquifer further exacerbates the issue of saline drinking water. Urgent measures are needed to address climate change, including improving water management, implementing integrated coastal zone planning, raising awareness among stakeholders, and implementing emergency projects to mitigate the impacts. Recommendations: To mitigate the adverse effects of climate change, several recommendations are provided. These include improving water management practices, developing integrated coastal zone planning strategies, raising awareness among all stakeholders, improving health and education, and implementing emergency projects to combat climate change. These measures aim to enhance adaptive capacity and resilience in the face of future climate change impacts.

Keywords: climate change, groundwater, coastal wetlands, Yemen

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Authors: Eman Al-khateeba, Ebaa Al-Zayadneha, Osama Al-Dalahmahb, Zeinab Alawadib, Faisal Khatiba, Randa Naffaa, Yanal Shafagoj

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The purpose of the current study was to examine the association of plasma copper and lipid concentrations with changes in cognitive function in elderly Jordanian individuals. The study population consisted of two groups; 52 subjects with dementia, and 50 controls. All individuals were screened with Mini-Mental State Examination (MMSE) and Clock drawing test (CDT).Serum copper and lipid profile were assessed in all subjects, and the results were statistically evaluated at P < 0.05 level of significance. Dementia group had 10.1 % higher copper levels than controls however the difference was not statistically significant. No significant differences could be found between the two groups in lipid profile levels. There was no significant correlation between serum copper, lipid profile and cognitive decline in elderly Jordanians. Demographic variables indicate that educational level less than 12 years and illiterate demonstrated a 3.29 fold (p=0.026) and 6.29 fold (p=0.002) increase in risk of developing dementia, respectively. While coffee intake showed a protective effect against cognitive decline with 6.25 fold lower risk with increased coffee intake.

Keywords: copper, cholesterol, dementia, Alzheimer's disease, lipid profile, coffee

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Authors: Hannah Gutmann, Rick Richardson, Richard Bryant

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Intrusive memories following a traumatic event are not uncommon. However, in some individuals, these memories become maladaptive and lead to prolonged stress reactions. A seminal model of PTSD explains that aberrant processing during trauma may lead to prolonged stress reactions and intrusive memories. This model explains that elevated arousal at the time of the trauma promotes data driven processing, leading to fragmented and intrusive memories. This study investigated the role of elevated arousal on the development of intrusive memories. We measured salivary markers of arousal and investigated what impact this had on data driven processing, memory fragmentation, and subsequently, the development of intrusive memories. We assessed 100 healthy participants to understand their processing style, arousal, and experience of intrusive memories. Participants were randomised to a control or experimental condition, the latter of which was designed to increase their arousal. Based on current theory, participants in the experimental condition were expected to engage in more data driven processing and experience more intrusive memories than participants in the control condition. This research aims to shed light on the mechanisms underlying the development of intrusive memories to illustrate ways in which therapeutic approaches for PTSD may be augmented for greater efficacy.

Keywords: stress, cortisol, SAA, PTSD, intrusive memories

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Authors: Guebli Abdelkader, Reguieg Madani, Belkadi Adel, Sbaa Bouabdellah

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The identification of mechanical variables in the motor performance trajectory has a prominent role in improving skill performance, error-exceeding, it contributes seriously to solving some problems of learning and training. The study aims to highlight the indicators of motor performance for Paralympic athletes during the practicing sports between modelling and between excellence in motor performance, this by taking into account the distinction of athlete practicing with special behavioral skills for the Paralympic athletes. In the study, we relied on the analysis of some previous research of biomechanical performance indicators during some of the events sports (shooting activities in the Paralympic athletics, shooting skill in the wheelchair basketball). The results of the study highlight the distinction of disabled practitioners of sporting events identified in motor performance during practice, by overcoming some physics indicators in human movement, as a lower center of body weight, increase in offset distance, such resistance which requires them to redouble their efforts. However, the results of the study highlighted the strength of the correlation between biomechanical variables of motor performance and the digital level achievement similar to the other practitioners normal.

Keywords: sports, the disabled, motor performance, Paralympic

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Authors: Y. Yulnafatmawita, H. Hermansah

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Topography is a factor affecting soil characteristics. Chemical characteristics of a soil is a factor determining the productivity of the land. A research was conducted in Bukit Sarasah Padang, an area receiving > 5000 mm rainfall annually. The purpose of this research was to determine the chemical characteristics of soils at sequence topography in hill-slope of Bukit Sarasah. Soils were sampled at 3 different altitudes in the research area from 315 m – 515 m asl with 100 m interval. At each location, soil samples were taken from two depths (0-20 cm and 30-50 cm) for soil chemical characteristics (pH, CEC, organic-C, N-total, C/N, Ca-, Mg-, K-, Na-, Al-, and H-exchangeable). Based on the data resulted, it was found that there was a tendency of decreasing soil organic matter (SOC) content by increasing location from 315 to 515 m asl as well as from the top 0-20 cm to 30-50 cm soil depth. The same tendency was also found for the CEC, pH, N-total, and C/N ratio of the soil. On the other hand, exchangeable-Al and -H tended to increase by increasing elevation in Bukit Sarasah. There was no significant difference found for the concentration of exchangeable cations among the elevations and between the depths. The soil chemical characteristics on the top 20 cm were generally better than those on 30-50 cm soil depth, however, different elevation did not gave significant difference of the concentration.

Keywords: soil chemical characteristics, soil depths, topo-sequence, wet tropical area

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Authors: J. Janicki, M. Rom, C. Slusarczyk, J. Fabia, M. Siika-aho, K. Marjamaa, K. Kruus, K. Langfelder, C. Steel, M. Paloheimo, T. Puranen, S. Mäkinen, D. Wawro

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The cellulose is one of the most abundant polymers in the world, however, its application in the high-end value products such as films or fibres, it triggered by the cellulose properties. The noticeable presence of hydrogen bonding reflected with partially crystalline structure makes the cellulose insoluble in common solvents and not meltable. The existing technologies, such as viscose process, suffer from environmental and economical problems, because of the risk of harmful chemicals liberation during the spinning process. The enzymatic modification of cellulose with endoglucanase makes it directly alkali soluble in NaOH solution, giving the opportunities for film and fibers formation. As the effect of enzymatic treatment, there are observed changes in crystalline structure and accompanying changes of the affinity of cellulose to water, demonstrated by water retention value. The objective of the project ELMO - Novel carbohydrate modifying enzymes for fibre modification is is to develop new enzyme products for modification of dissolving grade pulps. The aim is to increase the reactivity of dissolving grade pulps and remove residual hemicellulose. The scientific aim of this paper is to present the effect of enzymatic treatment on the crystallinity and affinity to water of cellulose pulps modified with enzymes.

Keywords: cellulose, crystallinity, WAXS, enzyme

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