Search results for: significant risk factors in megaprojects
Commenced in January 2007
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Edition: International
Paper Count: 26812

Search results for: significant risk factors in megaprojects

5842 Experimental Study on the Effectiveness of Functional Training for Female College Students' Physical Fitness and Sport Skills

Authors: Yangming Zhu, Mingming Guo, Xiaozan Wang

Abstract:

Introduction: The purpose of this study is to integrate functional training into physical education to test the effectiveness of functional training in improving the physical fitness (PF) and sport skills (SS) of female college students. Methods: A total of 54 female college students from East China Normal University were selected for this study (27 in the experimental group and 27 in the control group), and 13 weeks of the experimental intervention was conducted during the semester. During the experimental period, the experimental group was functionally trained for 1 hour per week. The control group performed one-hour weekly sports (such as basketball, football, etc.) as usual. Before and after the experiment, the national students' physical fitness test was used to test the PF of the experimental group and the control group, and the SS of the experimental group and the control group were tested before and after the intervention. Then using SPSS and Excel to organize and analyze the data. Results: The independent sample T-test showed that there was no significant difference in the PF and SS between the experimental group and the control group before the experiment (T PF=71.86, p PF> 0.05, Tₛₛ=82.41,pₛₛ > 0.05); After the experiment, the PF of the experimental group was significantly higher than that of the control group (T Improve=71.86, p Improve < 0.05); after the experiment, the SS of the experimental group was significantly higher than that of the control group (Tₛₛ = 1.31, pₛₛ <0.01) Conclusions: Integrating functional training into physical education can improve the PF of female college students. At the same time, the integration of functional training into physical education can also effectively improve the SS of female college students. Therefore, it is suggested that functional training be integrated into the daily physical education of female college students so as to improve their PF and SS.

Keywords: functional training, physical fitness, sport skills, female college students

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5841 Phytoplankton Diversity and Abundance in Burullus Lagoon, Southern Mediterranean Coast, Egypt

Authors: Shymaa S. Zaher, Hesham M. Abd El-Fatah, Dina M. Ali

Abstract:

Burullus Lagoon is the second largest lake, along the Mediterranean seashore. It exposed to over nutrient enrichment from fish farming and agricultural drainage wastes. This study assesses the present status phytoplankton response to different flow events, including domestic, agricultural, industrial, and fish farms discharge in the three main sectors of Burullus Lagoon, to focus on the influence of environmental variables on phytoplankton species composition inhabiting the Lagoon. Twelve sites representing the eastern, central, and western basin were selected during winter and summer 2018. Among the most abundant group, Chlorophyceae came in the first rank by 37.9% of the total phytoplankton densities, Bacillariophyceae (29.31%), Cyanophyceae (20.7%), Euglenophyceae (8.63%) and Dinophyceae (3.4%). Cyclotella menenghiana was the most abundant diatoms, while Scenedesmus quadricauda, S. acuminatus, and S. bijuga were highly recorded nearby the drains (in the middle sector). Phytoplankton in Burullus Lagoon attained the lowest values during the winter season and the highest ones during the summer season. The total count of phytoplankton in the middle and western basin of the lake was higher than that of the eastern part. Excessive use of chemical fertilizers, pesticides, and washing out of nutrients loaded to the drainage water, leading to a significant pronounced decrease in community composition and standing crop of phytoplankton in Burullus Lake from year to year, hold the danger of shifting the lagoon ecosystem.

Keywords: Burullus Lagoon, environmental variables, phytoplankton, water pollution

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5840 Mortar Positioning Effects on Uniaxial Compression Behavior in Hollow Concrete Block Masonry

Authors: José Álvarez Pérez, Ramón García Cedeño, Gerardo Fajardo-San Miguel, Jorge H. Chávez Gómez, Franco A. Carpio Santamaría, Milena Mesa Lavista

Abstract:

The uniaxial compressive strength and modulus of elasticity in hollow concrete block masonry (HCBM) represent key mechanical properties for structural design considerations. These properties are obtained through experimental tests conducted on prisms or wallettes and depend on various factors, with the HCB contributing significantly to overall strength. One influential factor in the compressive behaviour of masonry is the thickness and method of mortar placement. Mexican regulations stipulate mortar placement over the entire net area (full-shell) for strength computation based on the gross area. However, in professional practice, there's a growing trend to place mortar solely on the lateral faces. Conversely, the United States of America standard dictates mortar placement and computation over the net area of HCB. The Canadian standard specifies mortar placement solely on the lateral face (Face-Shell-Bedding), where computation necessitates the use of the effective load area, corresponding to the mortar's placement area. This research aims to evaluate the influence of different mortar placement methods on the axial compression behaviour of HCBM. To achieve this, an experimental campaign was conducted, including: (1) 10 HCB specimens with mortar on the entire net area, (2) 10 HCB specimens with mortar placed on the lateral faces, (3) 10 prisms of 2-course HCB under axial compression with mortar in full-shell, (4) 10 prisms of 2-course HCB under axial compression with mortar in face-shell-bedding, (5) 10 prisms of 3-course HCB under axial compression with mortar in full-shell, (6) 10 prisms of 3-course HCB under axial compression with mortar in face-shell-bedding, (7) 10 prisms of 4-course HCB under axial compression with mortar in full-shell, and, (8) 10 prisms of 4-course HCB under axial compression with mortar in face-shell-bedding. A combination of sulphur and fly ash in a 2:1 ratio was used for the capping material, meeting the average compressive strength requirement of over 35 MPa as per NMX-C-036 standards. Additionally, a mortar with a strength of over 17 MPa was utilized for the prisms. The results indicate that prisms with mortar placed over the full-shell exhibit higher strength compared to those with mortar over the face-shell-bedding. However, the elastic modulus was lower for prisms with mortar placement over the full-shell compared to face-shell bedding.

Keywords: masonry, hollow concrete blocks, mortar placement, prisms tests

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5839 Anti-Melanogenesis and Anti-Inflammatory Effects of Opuntia humifusa

Authors: Yonghwa Lee, Yoon Suk Kim, Yongsub Yi

Abstract:

This study was to confirm the effects of anti-melanogenesis and anti-inflammatory effects from Opuntia humifusa fruit and stem extracts. A potent anti-oxidant activity was shown from the leaf extract at IC50 value of 38.33±1.07 μg/mL and fruit extract at IC50 value of 40.23±2.21 μg/mL by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Also, phenolic contents were confirmed total phenolic assay by high performance liquid chromatography (HPLC). Fraction of taxifolin from leaf extract was identified using HPLC and gas chromatography/mass spectrometry. The extracts of Opuntia humifusa fruit and stem were confirmed about toxicity effect in B16 F1 by cell viability. Melanin contents were decreased. Opuntia humifusa fruit and stem extracts had a positive effect of melanin synthesis inhibition for skin whitening. In investigating the anti-inflammatory activities of Opuntia humifusa, the results of cell viability indicated that taxifolin did not show cytotoxicity on RAW264.7 cells at 500 μM of concentration. The results show that taxifolin inhibited lipopolysaccharide (LPS)-induced production of Nitrite oxide (NO). In addition, taxifolin indicated the inhibition of lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF) -α and interleukin (IL) -6 productions by cytokine assay and cyclooxygenase (COX)-2 expression by western blot analysis, meaning that taxifolin had a significant anti-inflammatory effect. Our results suggested that taxifolin from Opuntia humifusa has anti-melanogenesis and anti-inflammatory activities.

Keywords: anti-melanogenesis, anti-inflammatory, Opuntia humifusa, taxifolin

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5838 The Impact of Resettlement Challenges in Seeking Employment on the Mental Health and Well-Being of African Refugee Youth in South Australia

Authors: Elvis Munyoka

Abstract:

While the number of African refugees settling in Australia has significantly increased since the mid-1990s, the marginalisation and exclusion of young people from refugee backgrounds in employment remain a critical challenge. Unemployment or underemployment can negatively impact refugees in multiple areas, such as income, housing, life satisfaction, and social status. Higher rates of unemployment among refugees are linked in part to the intersection of pre-migration and daily challenges like trauma, racism, gender identity, and English language competency, all of which generate multiple employability disadvantages. However, the intersection of gender, race, social class, and age in impacting African refugee youth’s access to employment has received less attention. Using a qualitative case study approach, the presentation will explore how gender, race, social class, and age influence African refugee youth graduates’ access to employment in South Australia. The intersectionality theory and capability approach to social justice is used to explore intersecting factors impacting African refugee youth’s access to employment in South Australia. Participants were 16 African refugee graduates aged 18-30 living in South Australia who took part in the study for one year. Based on the trends in the data, the results suggest that long-term unemployment and underemployment, coupled with ongoing racism and marginalisation, have the potential to make refugees more vulnerable to several mental disorders such as depression, hopelessness, and suicidal thoughts. The analysis also reveals that resettlement challenges may limit refugees’ ability to recover from pre-migration trauma. The impact of resettlement challenges on refugee mental health highlights the need for comprehensive policy interventions to address the barriers refugees face in finding employment in resettlement communities. With African refugees constituting such an important part of Australian society, they should have equal access to meaningful employment, as decent work promotes good mental health, successful resettlement, hope, and self-sufficiency.

Keywords: African refugees, employment, mental health, Australia, underemployment

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5837 Propranalol is Not Effective in Preventing the Progression to Severe Portal Hypertensive Gastropathy in Cirrhotic Patients who Had Undergone Variceal Eradication: A Randomised Controlled Trial

Authors: Jeffey George, Varghese Thomas

Abstract:

Background and Objectives: PHG is an important source of gastrointestinal bleeding in patients with portal hypertension. Aim: To assess the progression to severe portal hypertensive gastropathy(PHG) in patients with cirrhosis who were treated with maximum tolerated dose of propranalol, after variceal eradication to grade II or below. Methods: Cirrhotic patients(child A and B) presenting with upper gastrointestinal bleeding with endoscopic findings of mild or no PHG were followed up over 6 months after variceal eradication to assess the progression to severe PHG. Included patients were randomised to either maximum tolerated doses of propranalol (group A) or to no treatment (group B). Primary end point of the study were the development of gastrointestinal bleed, evidence of hepatic decompensation and death. Progression to severe PHG were compared between the two groups. Results: 56 patients (49 males) were enrolled (group A = 28, group B = 28). 8 patients were excluded from final analysis (gi bleed=5, encephalopathy=2,HCC=1 including 4 deaths).3 patients were lost to follow-up, and 1 developed intolerance to propranalol. Mean dose of propranalol used was 60 mg per day. Progression to severe PHG in the fundus over 6 months was 23.8% in group A versus 15.8 % in group B (p = 0.52). Severe PHG was noted in body in 14.3% in group A versus 21.1% in group B (p = 0.57). 23.8 % in group A had progression to severe PHG compared with 15.8 % in group B (p =0.52). There was no statistically significant difference in the progression of PHG between the two groups(p=0.43). Conclusion: In this short term study propranalol was found not to prevent the progression to severe portal hypertensive gastropathy in cirrhotic patients who had undergone endotherapy for esophageal varices.

Keywords: propranalol, portal hypertensive gastropathy, cirrhotic patients, gastroenterology

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5836 Projections of Climate Change in the Rain Regime of the Ibicui River Basin

Authors: Claudineia Brazil, Elison Eduardo Bierhals, Francisco Pereira, José Leandro Néris, Matheus Rippel, Luciane Salvi

Abstract:

The global concern about climate change has been increasing, since the emission of gases from human activities contributes to the greenhouse effect in the atmosphere, indicating significant impacts to the planet in the coming years. The study of precipitation regime is fundamental for the development of research in several areas. Among them are hydrology, agriculture, and electric sector. Using the climatic projections of the models belonging to the CMIP5, the main objective of the paper was to present an analysis of the impacts of climate change without rainfall in the Uruguay River basin. After an analysis of the results, it can be observed that for the future climate, there is a tendency, in relation to the present climate, for larger numbers of dry events, mainly in the winter months, changing the pluviometric regime for wet summers and drier winters. Given this projected framework, it is important to note the importance of adequate management of the existing water sources in the river basin, since the value of rainfall is reduced for the next years, it may compromise the dynamics of the ecosystems in the region. Facing climate change is fundamental issue for regions and cities all around the world. Society must improve its resilience to phenomenon impacts, and spreading the knowledge among decision makers and citizens is also essential. So, these research results can be subsidies for the decision-making in planning and management of mitigation measures and/or adaptation in south Brazil.

Keywords: climate change, hydrological potential, precipitation, mitigation

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5835 Multi-Temporal Mapping of Built-up Areas Using Daytime and Nighttime Satellite Images Based on Google Earth Engine Platform

Authors: S. Hutasavi, D. Chen

Abstract:

The built-up area is a significant proxy to measure regional economic growth and reflects the Gross Provincial Product (GPP). However, an up-to-date and reliable database of built-up areas is not always available, especially in developing countries. The cloud-based geospatial analysis platform such as Google Earth Engine (GEE) provides an opportunity with accessibility and computational power for those countries to generate the built-up data. Therefore, this study aims to extract the built-up areas in Eastern Economic Corridor (EEC), Thailand using day and nighttime satellite imagery based on GEE facilities. The normalized indices were generated from Landsat 8 surface reflectance dataset, including Normalized Difference Built-up Index (NDBI), Built-up Index (BUI), and Modified Built-up Index (MBUI). These indices were applied to identify built-up areas in EEC. The result shows that MBUI performs better than BUI and NDBI, with the highest accuracy of 0.85 and Kappa of 0.82. Moreover, the overall accuracy of classification was improved from 79% to 90%, and error of total built-up area was decreased from 29% to 0.7%, after night-time light data from the Visible and Infrared Imaging Suite (VIIRS) Day Night Band (DNB). The results suggest that MBUI with night-time light imagery is appropriate for built-up area extraction and be utilize for further study of socioeconomic impacts of regional development policy over the EEC region.

Keywords: built-up area extraction, google earth engine, adaptive thresholding method, rapid mapping

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5834 National Culture, Personal Values, and Supervisors’ Ethical Behavior: Examining a Partial Mediation Model of Merton’s Anomie Theory

Authors: Kristine Tuliao

Abstract:

Although it is of primary concern to ensure that supervisors behave appropriately, research shows that unethical behaviors are prevalent and may cost organizations’ economic and reputational damages. Nevertheless, few studies have considered the roles of the different levels of values in shaping one’s ethicality, and the examination of the possible mediation in the process of their influence has been rarely done. To address this gap, this research employs Merton’s anomie theory in designing a mediation analysis to test the direct impacts of national cultural values on supervisors’ justification of unethical behaviors as well as their indirect impacts through personal values. According to Merton’s writings, individual behaviors are affected by the society’s culture given its role in defining the members’ goals as well as the acceptable methods of attaining those goals. Also, Merton’s framework suggests that individuals develop their personal values depending on the assimilation of their society’s culture. Using data of 9,813 supervisors across 30 countries, results of hierarchical linear modeling (HLM) indicated that national cultural values, specifically assertiveness, performance orientation, in-group collectivism, and humane orientation, positively affect supervisors’ unethical inclination. Some cultural values may encourage unethical tendencies, especially if they urge and pressure individuals to attain purely monetary success. In addition, some of the influence of national cultural values went through personal monetary and non-monetary success values, indicating partial mediation. These findings substantiated the assertions of Merton’s anomie theory that national cultural values influence supervisors’ ethics through their integration with personal values. Given that some of the results contradict Merton’s anomie theory propositions, complementary arguments, such as incomplete assimilation of culture, and the probable impact of job position in perceptions, values, and behaviors, could be the plausible rationale for these outcomes. Consequently, this paper advances the understanding of differences in national and personal values and how these factors impact supervisors’ justification of unethical behaviors. Alongside these contributions, suggestions are presented for the public and organizations to craft policies and procedures that will minimize the tendency of supervisors to commit unethical acts.

Keywords: mediation model, national culture, personal values, supervisors' ethics

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5833 Assessment of the Use of Participatory Research Methods among Researchers in Federal University of Agriculture Abeokuta, Nigeria

Authors: Samson Olusegun Apantaku, Adetayo K. Aromolaran, Giyatt Hammed

Abstract:

The study assessed the use of participatory research methods among Federal University of Agriculture Abeokuta, Nigeria (FUNAAB) researchers. Simple random sampling technique was used to select one hundred and twenty respondents from the study area. Data were collected using a questionnaire. Data collected were subjected to descriptive and inferential statistical analyses. Results showed that 75.8% of the respondents were males while only 21.3% were female. The mean age of the respondents was 38.8 years and most (77.5%) of them were married. 15% of the respondents were in professorial cadre, 21.7% and 20% of the respondents were senior lecturers/fellow and lecturer/research fellow I&II respectively. The results further revealed that 93.3% of the respondents were aware of participatory research methods and 82.5% of the respondents have utilized it before. The average period of usage was 2.7 years and participation by consultation (86.7%) and interactive participation (76.7%) were mostly used. Most (94.2%) indicated that fund was the major hindrance to the use of participatory research methods. The result of correlation analysis showed that there was significant relationship between the years of research experience, designation post (status) of the respondents and usage of participatory research methods (r = 0.034, 0.031, p < 0.05). The study concluded that most of the researchers were aware of and used participatory research methods, which could influence the quality of their research or make it acceptable to the end users. It was recommended that more funds should be made available and accessible for participatory research. All researchers should be trained and encouraged to make use of participatory research methods in their research activities so as to achieve effective research and capacity building that could enhance adoption of technologies and increase agricultural production in the country. Farmers’ capacity to participate in agricultural research should also be enhanced.

Keywords: participatory research, participatory research methods, awareness, utilization

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5832 The Effects of Stand Density, Standards and Species Composition on Biomass Production in Traditional Coppices

Authors: Marek Mejstřík, Radim Matula, Martin Šrámek

Abstract:

Traditional coppices and coppice-with-standards were widely used throughout Europe and Asia for centuries but were largely abandoned in the second half of the 19th century, especially in central and northwestern Europe. In the last decades, there has been a renewed interest in traditional coppicing for nature conservation and most often, for rapid woody biomass production. However, there is little information on biomass productivity of traditional coppices and what affects it. Here, we focused on the effects of stand density, standards and tree species composition on sprout biomass production in newly restored coppices in the Czech Republic. We measured sprouts and calculated sprout biomass 7 years after the harvest from 2013 resprouting stumps in two 4 ha experimental plots. Each plot was divided into 64 subplots with different densities of standards and sprouting stumps. Total sprout biomass declined with increasing density of standards, but the effect of standards differed significantly among studied species. Whereas increasing density of standards decreased sprout biomass in Quercus petraea and Carpinus betulus, it did not affect sprout biomass productivity in Acer campestre and Tilia cordata. Sprout biomass on stand-level increased linearly with an increasing number of sprouting stumps and we observed no leveling of this relationship even in the highest densities of stumps. We also found a significant shift in tree species composition with the steeply declining relative abundance of Quercus in favor of other studied tree species.

Keywords: traditional coppice, coppice with standards, sprout biomass, forest management

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5831 Patient Support Program in Pharmacovigilance: Foster Patient Confidence and Compliance

Authors: Atul Khurana, Rajul Rastogi, Hans-Joachim Gamperl

Abstract:

The pharmaceutical companies are getting more inclined towards patient support programs (PSPs) which assist patients and/or healthcare professionals (HCPs) in more desirable disease management and cost-effective treatment. The utmost objective of these programs is patient care. The PSPs may include financial assistance to patients, medicine compliance programs, access to HCPs via phone or online chat centers, etc. The PSP has a crucial role in terms of customer acquisition and retention strategies. During the conduct of these programs, Marketing Authorisation Holder (MAH) may receive information related to concerned medicinal products, which is usually reported by patients or involved HCPs. This information may include suspected adverse reaction(s) during/after administration of medicinal products. Hence, the MAH should design PSP to comply with regulatory reporting requirements and avoid non-compliance during PV inspection. The emergence of wireless health devices is lowering the burden on patients to manually incorporate safety data, and building a significant option for patients to observe major swings in reference to drug safety. Therefore, to enhance the adoption of these programs, MAH not only needs to aware patients about advantages of the program, but also recognizes the importance of time of patients and commitments made in a constructive manner. It is indispensable that strengthening the public health is considered as the topmost priority in such programs, and the MAH is compliant to Pharmacovigilance (PV) requirements along with regulatory obligations.

Keywords: drug safety, good pharmacovigilance practice, patient support program, pharmacovigilance

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5830 Representation of Islamophobia on Social Media: Facebook Comments Analysis

Authors: Nadia Syed

Abstract:

The digital age has inevitably changed the way in which hate crime is committed. The cyber world has become a highly effective means for individuals and groups to be targeted, harmed, and marginalized , largely through online medium. Facebook has become one of the fastest growing social media platforms. At the end of 2013, Facebook had 1,23bn monthly active users and 757 million daily users who log onto Facebook. Within this online space, there are also an increasing number of online virtual communities, and hate groups who are using this freedom to share a violent, Islamophobic and racist description which attempts to create a aggressive virtual environment. This paper is a research on the rise of Islamophobia and the role of media in spreading it. This paper focusing on how the media especially Facebook is portraying Islam as the religion which promotes violence and ultimately playing a significant role in the global rise of Islamophobia against Muslims. It is important to analyse these ‘new’ communities by monitoring the activities they conduct, because the material they post, potentially can have a harmful impact on community cohesion within society. Additionally, as a result of recent figures that shows an increase in online anti-Muslim abuse, there is a pertinent need to address the issue about Islamophobia on social media. On the whole, this study found Muslims being demonized and vilified online which had manifested through negative attitudes, discrimination, stereotypes, physical threats and online harassment which all had the potential to incite violence or prejudicial action because it disparages and intimidates a protected individual or group.

Keywords: Islamophobia, online, social media, facebook, internet, extremism

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5829 Using Polymerase Chain Reaction Technique to Observe the Resistant Strains of Pectinophora gossypiella against Cry1Ac Expressing Cotton

Authors: Zunnu Raen Akhtar, U. Irshad, M. Majid

Abstract:

Due to the widespread cultivation of transgenic cotton, intense selection pressure resulted in resistant allele in pink bollworm, Pectinophora gossypiella (Gelechiidae: Lepidoptera). A resistant strain of pink bollworm against transgenic cotton has become a challenge to Integrated Resistance Management (IRM) in the World. Laboratory and field studies were conducted to determine the resistant strains of pink bollworm by performing bioassay, extracting the DNA, conducting PCR of both laboratory as well as field collected pink bollworms to observe the developed resistance. In all of the studies, two Bt varieties FH-142 and FH-118 expressing Cry1Ac compared to non-Bt (Control) were tested against pink bollworm. In the laboratory, bioassay results showed that there was no significant mortality difference between Bt and non-Bt varieties. Similar mortality percentage was observed in transgenic and non-transgenic (control) variety. Insects which were survived after bioassay, as well as those collected from the Bt cotton fields, were selected for further molecular studies. DNA extraction followed by PCR was conducted to check the resistant strains in pink bollworm. In field studies, we also observed the population dynamics of pink boll worms on Bt as compared to non-Bt varieties. Laboratory and field studies confirmed that resistant strains occurs in Pakistani Bt cotton fields. Different strategies should be adopted to combat that serious prevailing resistance issues.

Keywords: transgenic cotton, resistance, pectinophora gossypiella, , integrated resistance management (IRM), polymerase chain reaction (PCR)

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5828 Automatic Reporting System for Transcriptome Indel Identification and Annotation Based on Snapshot of Next-Generation Sequencing Reads Alignment

Authors: Shuo Mu, Guangzhi Jiang, Jinsa Chen

Abstract:

The analysis of Indel for RNA sequencing of clinical samples is easily affected by sequencing experiment errors and software selection. In order to improve the efficiency and accuracy of analysis, we developed an automatic reporting system for Indel recognition and annotation based on image snapshot of transcriptome reads alignment. This system includes sequence local-assembly and realignment, target point snapshot, and image-based recognition processes. We integrated high-confidence Indel dataset from several known databases as a training set to improve the accuracy of image processing and added a bioinformatical processing module to annotate and filter Indel artifacts. Subsequently, the system will automatically generate data, including data quality levels and images results report. Sanger sequencing verification of the reference Indel mutation of cell line NA12878 showed that the process can achieve 83% sensitivity and 96% specificity. Analysis of the collected clinical samples showed that the interpretation accuracy of the process was equivalent to that of manual inspection, and the processing efficiency showed a significant improvement. This work shows the feasibility of accurate Indel analysis of clinical next-generation sequencing (NGS) transcriptome. This result may be useful for RNA study for clinical samples with microsatellite instability in immunotherapy in the future.

Keywords: automatic reporting, indel, next-generation sequencing, NGS, transcriptome

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5827 Determination of MDA by HPLC in Blood of Levofloxacin Treated Rats

Authors: D. S. Mohale, A. P. Dewani, A. S.tripathi, A. V. Chandewar

Abstract:

Present work demonstrates the applicability of high-performance liquid chromatography (HPLC) with UV-Vis detection for the quantification of malondialdehyde as malondialdehyde-thiobarbituric acid complex (MDA-TBA) in-vivo in rats. The HPLC method for MDA-TBA was achieved by isocratic mode on a reverse-phase C18 column (250mm×4.6mm) at a flow rate of 1.0mLmin−1 followed by detection at 532 nm. The chromatographic conditions were optimized by varying the concentration and pH of water followed by changes in percentage of organic phase optimal mobile phase consisted of mixture of water (0.2% triethylamine pH adjusted to 2.3 by ortho-phosphoric acid) and acetonitrile in ratio (80:20v/v). The retention time of MDA-TBA complex was 3.7 min. The developed method was sensitive as limit of detection and quantification (LOD and LOQ) for MDA-TBA complex were (standard deviation and slope of calibration curve) 110 ng/ml and 363 ng/ml respectively. Calibration studies were done by spiking MDA into rat plasma at concentrations ranging from 500 to 1000 ng/ml. The precision of developed method measured in terms of relative standard deviations for intra-day and inter-day studies was 1.6–5.0% and 1.9–3.6% respectively. The HPLC method was applied for monitoring MDA levels in rats subjected to chronic treatment of levofloxacin (LEV) (5mg/kg/day) for 21 days. Results were compared by findings in control group rats. Mean peak areas of both study groups was subjected for statistical treatment to unpaired student t-test to find p-values. The p value was <0.001 indicating significant results and suggesting increased MDA levels in rats subjected to chronic treatment of LEV of 21 days.

Keywords: malondialdehyde-thiobarbituric acid complex, levofloxacin, HPLC, oxidative stress

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5826 Caught in the Crossfire : Natural Resources, Energy Transition, and Conflict in the Democratic Republic of Congo

Authors: Koami West Togbetse

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The global shift towards clean and sustainable energy sources, known as the energy transition, is compelling numerous countries to transition from polluting energy systems to cleaner alternatives, commonly referred to as green energies. In this context, cobalt holds significant importance as a crucial mineral in facilitating this energy transition due to its pivotal role in electric batteries. Considering the Democratic Republic of Congo’s reputation for political instability and its position as the largest producer of cobalt, possessing over 50% of the world’s reserves, we have assessed the potential conflicts that may arise as a result of the rapid increase in cobalt demand. The results show that cobalt does not appear to be a determinant contributing to all past conflicts over the study period in the Democratic Republic of Congo (DRC). Gold, on the other hand, stands out as one of the coveted metals for rebel groups engaged in rampant exploitation, increasing the likelihood of conflicts occurring. However, a more in-depth analysis reveals a shift in the relationship between cobalt production and conflict events around 2006. Prior to 2006, increased cobalt production was significantly associated with a reduction in conflict events. However, after 2006, this relationship became positive, indicating that higher cobalt production is now linked to a slight increase in conflict events. This suggests a change in the dynamics affecting conflicts related to cobalt production before and after 2006. According to our predictive model, cobalt has the potential to emerge increasingly as a contributing factor, just like gold.

Keywords: conflicts, natural resources, energy transition, geopolitics

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5825 Investigation of Bending Behavior of Ultra High Performance Concrete with Steel and Glass Fiber Polymer Reinforcement

Authors: Can Otuzbir

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It is one of the most difficult areas of civil engineering to provide long-lasting structures with the rapid development of concrete and reinforced concrete structures. Concrete is a living material, and the structure where the concrete is located is constantly exposed to external influences. One of these effects is reinforcement corrosion. Reinforcement corrosion of reinforced concrete structures leads to a significant decrease in the carrying capacity of the structural elements, as well as reduced service life. It is undesirable that the service life should be completed sooner than expected. In recent years, advances in glass fiber technology and its use with concrete have developed rapidly. As a result of inability to protect steel reinforcements against corrosion, fiberglass reinforcements have started to be investigated as an alternative material to steel reinforcements, and researches and experimental studies are still continuing. Glass fiber reinforcements have become an alternative material to steel reinforcement because they are resistant to corrosion, lightweight and simple to install compared to steel reinforcement. Glass fiber reinforcements are not corroded and have higher tensile strength, longer life, lighter and insulating properties compared to steel reinforcement. In experimental studies, glass fiber reinforcements have been shown to show superior mechanical properties similar to beams produced with steel reinforcement. The performance of long-term use of glass fiber fibers continues with accelerated experimental studies.

Keywords: glass fiber polymer reinforcement, steel fiber concrete, ultra high performance concrete, bending, GFRP

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5824 Neighborhood Linking Social Capital as a Predictor of Drug Abuse: A Swedish National Cohort Study

Authors: X. Li, J. Sundquist, C. Sjöstedt, M. Winkleby, K. S. Kendler, K. Sundquist

Abstract:

Aims: This study examines the association between the incidence of drug abuse (DA) and linking (communal) social capital, a theoretical concept describing the amount of trust between individuals and societal institutions. Methods: We present results from an 8-year population-based cohort study that followed all residents in Sweden, aged 15-44, from 2003 through 2010, for a total of 1,700,896 men and 1,642,798 women. Social capital was conceptualized as the proportion of people in a geographically defined neighborhood who voted in local government elections. Multilevel logistic regression was used to estimate odds ratios (ORs) and between-neighborhood variance. Results: We found robust associations between linking social capital (scored as a three level variable) and DA in men and women. For men, the OR for DA in the crude model was 2.11 [95% confidence interval (CI) 2.02-2.21] for those living in areas with the lowest vs. highest level of social capital. After accounting for neighborhood-level deprivation, the OR fell to 1.59 (1.51-1-68), indicating that neighborhood deprivation lies in the pathway between linking social capital and DA. The ORs remained significant after accounting for age, sex, family income, marital status, country of birth, education level, and region of residence, and after further accounting for comorbidities and family history of comorbidities and family history of DA. For women, the OR decreased from 2.15 (2.03-2.27) in the crude model to 1.31 (1.22-1.40) in the final model, adjusted for multiple neighborhood-level and individual-level variables. Conclusions: Our study suggests that low linking social capital may have important independent effects on DA.

Keywords: drug abuse, social linking capital, environment, family

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5823 Metaphorical Devices in Political Cartoons with Reference to Political Confrontation in Pakistan after Panama Leaks

Authors: Ayesha Ashfaq, Muhammad Ajmal Ashfaq

Abstract:

It has been assumed that metaphorical and symbolic contests are waged with metaphors, captions, and signs in political cartoons that play a significant role in image construction of political actors, situations or events in the political arena. This paper is an effort to explore the metaphorical devices in political cartoons related to the political confrontation in Pakistan between the ruling party Pakistan Muslim League Nawaz (PMLN) and opposition parties especially after Panama leaks. For this purpose, political cartoons sketched by five renowned political cartoonists on the basis of their belongings to the most highly circulated mainstream English newspapers of Pakistan and their professional experiences in their genre, were selected. The cartoons were analyzed through the Barthes’s model of Semiotics under the umbrella of the first level of agenda setting theory ‘framing’. It was observed that metaphorical devices in political cartoons are one of the key weapons of cartoonists’ armory. These devices are used to attack the candidates and contribute to the image and character building. It was found that all the selected political cartoonists used different forms of metaphors including situational metaphors and embodying metaphors. Not only the physical stature but also the debates and their activities were depicted metaphorically in the cartoons that create the scenario of comparison between the cartoons and their real political confrontation. It was examined that both forms of metaphors shed light on cartoonist’s perception and newspaper’s policy about political candidates, political parties and particular events. In addition, it was found that zoomorphic metaphors and metaphors of diminishments were also predominantly used to depict the conflict between two said political actors.

Keywords: metaphor, Panama leaks, political cartoons, political communication

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5822 Stock Market Development and the Growth of Nigerian Economy

Authors: Godwin Chigozie Okpara, Eugene Iheanacho

Abstract:

This paper examined the dynamic behavior of stock market development and the growth of Nigerian economy. The variables; market capitalization ratio, turnover ratio and liquidity proxies by the ratio of market capitalization to gross domestic product were sourced and computed from the Nigerian stock exchange fact books and the CBN statistical bulletin of the Central Bank of Nigeria. The variables were tested and found stationary and cointregrated using the augumented Dickey Fuller unit root test and the Johnson cointegration test respectively. The dynamic behavior of the stock market development model was verified using the error correction model. The result shows that about 0.4l percent of the short run deviation is corrected every year and also reveals that market capitalization ratio and market liquidity are positive and significant function of economic growth. In other words market capitalization ratio and liquidity positively and significantly impact economic growth. Market development variables such as turnover ratio and market restriction can exert positive but insignificant impact on the growth of the economy suggesting that securities transaction relative to the size of the securities market are not high enough to significantly engender economic growth in Nigeria. In the light of this, the researchers recommend that the regulatory body as well as the government, should provide a conducive environment capable of encouraging the growth and development of the stock market. This if well articulated will enhance the market turnover and the growth of the economy.

Keywords: market capitalization ratio, turnover ratio, liquidity, unit root test, cointegration

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5821 Study of Pseudomonas as Biofertiliser in Salt-Affected Soils of the Northwestern Algeria: Solubilisation of Calcium Phosphate and Growth Promoting of Broad Bean (Vcia faba)

Authors: A. Djoudi, R. Djibaou, H. A. Reguieg Yssaad

Abstract:

Our study focuses on the study of a bacteria belonging to Pseudomonas solubilizing tricalcium phosphate. They were isolated from rhizosphere of a variety of broad bean grown in salt-affected soils (electrical conductivity between 4 and 8 mmhos/cm) of the irrigated perimeter of Mina in northwestern Algeria. Isolates which have advantageous results in the calcium phosphate solubilization index test were subjected to identification using API20 then used to re-inoculate the same soil in pots experimentation to assess the effects of inoculation on the growth of the broad bean (Vicia faba). Based on the results obtained from the in-vitro tests, two isolates P5 and P8 showed a significant effect on the solubilization of tricalcium phosphate with an index I estimated at 314% and 283% sequentially. According to the results of in-vivo tests, the inoculation of the soil with P5 and P8 were significantly and positively influencing the growth in biometric parameters of the broad bean. Inoculation with strain P5 has promoted the growth of the broad bean in stem height, stem fresh weight and stem dry weight of 108.59%, 115.28%, 104.33%, respectively. Inoculation with strain P8 has fostered the growth of the broad bean stem fresh weight of 112.47%. The effect of Pseudomonas on the development of Vicia faba is considered as an interesting process by which PGPR can increase biological production and crop protection.

Keywords: Pseudomonas, Vicia faba, promoting of plant growth, solubilization tricalcium phosphate

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5820 Developing a GIS-Based Tool for the Management of Fats, Oils, and Grease (FOG): A Case Study of Thames Water Wastewater Catchment

Authors: Thomas D. Collin, Rachel Cunningham, Bruce Jefferson, Raffaella Villa

Abstract:

Fats, oils and grease (FOG) are by-products of food preparation and cooking processes. FOG enters wastewater systems through a variety of sources such as households, food service establishments, and industrial food facilities. Over time, if no source control is in place, FOG builds up on pipe walls, leading to blockages, and potentially to sewer overflows which are a major risk to the Environment and Human Health. UK water utilities spend millions of pounds annually trying to control FOG. Despite UK legislation specifying that discharge of such material is against the law, it is often complicated for water companies to identify and prosecute offenders. Hence, it leads to uncertainties regarding the attitude to take in terms of FOG management. Research is needed to seize the full potential of implementing current practices. The aim of this research was to undertake a comprehensive study to document the extent of FOG problems in sewer lines and reinforce existing knowledge. Data were collected to develop a model estimating quantities of FOG available for recovery within Thames Water wastewater catchments. Geographical Information System (GIS) software was used in conjunction to integrate data with a geographical component. FOG was responsible for at least 1/3 of sewer blockages in Thames Water waste area. A waste-based approach was developed through an extensive review to estimate the potential for FOG collection and recovery. Three main sources were identified: residential, commercial and industrial. Commercial properties were identified as one of the major FOG producers. The total potential FOG generated was estimated for the 354 wastewater catchments. Additionally, raw and settled sewage were sampled and analysed for FOG (as hexane extractable material) monthly at 20 sewage treatment works (STW) for three years. A good correlation was found with the sampled FOG and population equivalent (PE). On average, a difference of 43.03% was found between the estimated FOG (waste-based approach) and sampled FOG (raw sewage sampling). It was suggested that the approach undertaken could overestimate the FOG available, the sampling could only capture a fraction of FOG arriving at STW, and/or the difference could account for FOG accumulating in sewer lines. Furthermore, it was estimated that on average FOG could contribute up to 12.99% of the primary sludge removed. The model was further used to investigate the relationship between estimated FOG and number of blockages. The higher the FOG potential, the higher the number of FOG-related blockages is. The GIS-based tool was used to identify critical areas (i.e. high FOG potential and high number of FOG blockages). As reported in the literature, FOG was one of the main causes of sewer blockages. By identifying critical areas (i.e. high FOG potential and high number of FOG blockages) the model further explored the potential for source-control in terms of ‘sewer relief’ and waste recovery. Hence, it helped targeting where benefits from implementation of management strategies could be the highest. However, FOG is still likely to persist throughout the networks, and further research is needed to assess downstream impacts (i.e. at STW).

Keywords: fat, FOG, GIS, grease, oil, sewer blockages, sewer networks

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5819 Surface Modified Thermoplastic Polyurethane and Poly(Vinylidene Fluoride) Nanofiber Based Flexible Triboelectric Nanogenerator and Wearable Bio-Sensor

Authors: Sk Shamim Hasan Abir, Karen Lozano, Mohammed Jasim Uddin

Abstract:

Over the last few years, nanofiber-based triboelectric nanogenerator (TENG) has caught great attention among researchers all over the world due to its inherent capability of converting mechanical energy to usable electrical energy. In this study, poly(vinylidene fluoride) (PVDF) and thermoplastic polyurethane (TPU) nanofiber prepared by Forcespinning® (FS) technique were used to fabricate TENG for self-charging energy storage device and biomechanical body motion sensor. The surface of the TPU nanofiber was modified by uniform deposition of thin gold film to enhance the frictional properties; yielded 254 V open-circuit voltage (Voc) and 86 µA short circuit current (Isc), which were 2.12 and 1.87 times greater in contrast to bare PVDF-TPU TENG. Moreover, the as-fabricated PVDF-TPU/Au TENG was tested against variable capacitors and resistive load, and the results showed that with a 3.2 x 2.5 cm2 active contact area, it can quick charge up to 7.64 V within 30 seconds using a 1.0 µF capacitor and generate significant 2.54 mW power, enough to light 75 commercial LEDs (1.5 V each) by the hand tapping motion at 4 Hz (240 beats per minutes (bpm)) load frequency. Furthermore, the TENG was attached to different body parts to capture distinctive electrical signals for various body movements, elucidated the prospective usability of our prepared nanofiber-based TENG in wearable body motion sensor application.

Keywords: biomotion sensor, forcespinning, nanofibers, triboelectric nanogenerator

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5818 Nanoparticles Made of Amino Acid Derived Biodegradable Polymers as Promising Drug Delivery Containers

Authors: Sophio Kobauri, Tengiz Kantaria, Temur Kantaria, David Tugushi, Nina Kulikova, Ramaz Katsarava

Abstract:

Polymeric disperse systems such as nanoparticles (NPs) are of high interest for numerous applications in contemporary medicine and nanobiotechnology to a considerable potential for treatment of many human diseases. The important technological advantages of NPs usage as drug carriers (nanocontainers) are their high stability, high carrier capacity, feasibility of encapsulation of both hydrophilic or hydrophobic substances, as well as a high variety of possible administration routes, including oral application and inhalation. NPs can also be designed to allow controlled (sustained) drug release from the matrix. These properties of NPs enable improvement of drug bioavailability and might allow drug dosage decrease. The targeted and controlled administration of drugs using NPs might also help to overcome drug resistance, which is one of the major obstacles in the control of epidemics. Various degradable and non-degradable polymers of both natural and synthetic origin have been used for NPs construction. One of the most promising for the design of NPs are amino acid-based biodegradable polymers (AABBPs) which can clear from the body after the fulfillment of their function. The AABBPs are composed of naturally occurring and non-toxic building blocks such as α-amino acids, fatty diols and dicarboxylic acids. The particles designed from these polymers are expected to have an improved bioavailability along with a high biocompatibility. The present work deals with a systematic study of the preparation of NPs by cost-effective polymer deposition/solvent displacement method using AABBPs. The influence of the nature and concentration of surfactants, concentration of organic phase (polymer solution), and the ratio organic phase/inorganic(water) phase, as well as of some other factors on the size of the fabricated NPs have been studied. It was established that depending on the used conditions the NPs size could be tuned within 40-330 nm. At the next step of this research was carried out an evaluation of biocompability and bioavailability of the synthesized NPs using a stable human cell culture line – A549. It was established that the obtained NPs are not only biocompatible but they stimulate the cell growth.

Keywords: amino acids, biodegradable polymers, bioavailability, nanoparticles

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5817 Tertiary Education Trust Fund Intervention Projects and Resource Utilization in Universities in South Western States, Nigeria

Authors: Oluwlola Felicia Kikelomo

Abstract:

This study examined the influence of Tertiary Education Trust Fund (TETF) intervention projects and resource utilization in universities in South Western State of Nigeria. The study was a descriptive design of the correlation type. Purposive sampling technique was used to select six out of 14 beneficiary universities in the States. Instruments used to collect data were TETF Intervention Projects Checklist (TETFIPC), Educational Facilities Checklists (EFC) and Resources Utilization Checklists (RUC). The research questions raised were answered using percentage and utilization rates, while Pearson product-moment correlation statistic was used to test the hypotheses formulated to guide the study 0.05 level of significance. Findings of the study indicated that building construction had the highest TETF allocation (64.5%), while staff development opportunities had the least (1.1%) in the sampled universities. Significant and positive relationship existed between time and space utilization rates and student academic performance in the universities (r (1,800) = 0.63 and r (1,800) = 0.59, p ≤ 0.05 respectively). Based, on these findings, it was recommended that there should be periodic evaluation of completed TETF projects and utilization to ensure that TETF funds are properly used for the approved projects; and that TETF should improve on the provision of educational facilities to universities for staff and students’ use through increase in education tax from 2% to 4% with collaboration with the world bank and other funding agencies as being practiced in other countries of the world such as Norway, Spain, and United Kingdom.

Keywords: tertiary education trust fund, intervention, education, human development

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5816 The Role of Ecotourism Development in the Financing of Conservation Initiatives in Cameroon’s Protected Areas: Lessons from the Campo Ma’an National Park

Authors: Nyong Princely Awazi, Gadinga Walter Forje, Barnabas Neba Nfornkah, Ndzifon Jude Kimengsi

Abstract:

Ecotourism is documented as a sustainable measure of bridging conservation goals and livelihood sustenance around protected areas, due to its ability of not just providing alternative livelihood, but also in providing the necessary resources that can help finance conservation initiatives. In Cameroon, all ecotourism activities around national parks are aimed at generating revenue through the conservation service while providing sustainable livelihood options to the local population. There exists an information lacuna regarding the contribution of ecotourism finances to conservation efforts in the country. This study was aimed at establishing the contribution of ecotourism finances to conservation initiatives in and around the Campo Ma’an National Park (CMNP). Data were collected through the administering of 120 structured questionnaires to ecotourism actors and 15 key/expert interviews with tourism and conservation actors in the Campo Ma’an landscape. Chi-square test, Spearman’s rank correlation and regressions were used for data analysis. The study revealed that the main sources of ecotourism financing to the park service are through entrance fees, cameras and vehicle fees paid by tourists as well as ecotourism project financing through NGOs. Calculations from the tourism register of the park showed that the park was able to raise as much as 1,576,000 FCFA (US$ 3,152) annually. It was further established that ecotourism revenue has not greatly supported conservation, with 54% of respondents perceiving ecotourism not contributing to biodiversity conservation. Chi Square test results highlighted poor ecotourism governance, low level of ecotourism development, corruption from park management staff, obsolete nature of the current finance law on the management of protected area revenue as key factors hindering ecotourism financing in conservation. For ecotourism financing to contribute to biodiversity conservation in the CMNP and in Cameroon’s protected areas, the government needs to revise the finance law on the management of revenue generated from protected areas, improve park governance to fight corruption and enhance transparency, invest in the development and marketing of the Campo Ma’an national park as a tourism destination in the country.

Keywords: Cameroon, Campo Ma’an National Park, conservation, ecotourism, ecotourism financing

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5815 Combined Application of Rice-Straw Biochar and Poultry Manure Promotes Nutrient Uptake and Yield of Capsicum Frutescens

Authors: Fawibe O. O., Mustafa A. A., Oyelakin A. S., Dada O. A., Ojo E. S.

Abstract:

Field experiment was carried out during the cropping season of 2021 to examine the influence of the sole or combined application of rice-straw biochar and poultry manure on yield, nutrient uptake, and physiological attributes of Capsicum frutescens. The experiment was a randomized complete block design with five replicates. Treatments were 10 t/ha biochar (BC), 5 t/ha biochar + 5 t/ha poultry manure (BC+PM), 10 t/ha poultry manure (PM), and no amendment as the control (NA ). Parameters determined were fruit yield, aboveground biomass, macro and micro nutrients in leaves, antinutrients content, and pigments (chlorophyll a, chlorophyll b, and carotenoids) concentration. Data were analysed with one-way analysis of variance, while means were separated using Duncan’s Multiple Range Test at p<0.05. Soil amended with PM increased the nitrogen content of C. frutescens leaves by 40.9%, while polyphenol and phytic acid were reduced by 20.5% and 29.2%, respectively, compared with NA. Moreover, PM increased chlorophyll a and chlorophyll b by 91.9% and 16.4%, whereas proline was reduced by 31.3% compared with NA. However, PM and BC+PM had comparable influence on pigments, nutrients and antinutrients contents of C. frutescens. BC+PM significantly increased yield and aboveground biomass of C. frutescens by 52.9% and 99.2%, respectively, compared with NA. BC had no significant influence on the yield and nutrient uptake of C. frutescens compared with NA. In conclusion, sole application of poultry manure or combined with rice-straw biochar increased yield and nutrients availability in the leaves of C. frutescens.

Keywords: capsicum frutescens, biochar, nutrient uptake, poultry manure, organic amendment

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5814 Space Time Adaptive Algorithm in Bi-Static Passive Radar Systems for Clutter Mitigation

Authors: D. Venu, N. V. Koteswara Rao

Abstract:

Space – time adaptive processing (STAP) is an effective tool for detecting a moving target in spaceborne or airborne radar systems. Since airborne passive radar systems utilize broadcast, navigation and excellent communication signals to perform various surveillance tasks and also has attracted significant interest from the distinct past, therefore the need of the hour is to have cost effective systems as compared to conventional active radar systems. Moreover, requirements of small number of secondary samples for effective clutter suppression in bi-static passive radar offer abundant illuminator resources for passive surveillance radar systems. This paper presents a framework for incorporating knowledge sources directly in the space-time beam former of airborne adaptive radars. STAP algorithm for clutter mitigation for passive bi-static radar has better quantitation of the reduction in sample size thereby amalgamating the earlier data bank with existing radar data sets. Also, we proposed a novel method to estimate the clutter matrix and perform STAP for efficient clutter suppression based on small sample size. Furthermore, the effectiveness of the proposed algorithm is verified using MATLAB simulations in order to validate STAP algorithm for passive bi-static radar. In conclusion, this study highlights the importance for various applications which augments traditional active radars using cost-effective measures.

Keywords: bistatic radar, clutter, covariance matrix passive radar, STAP

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5813 Detection and Quantification of Viable but Not Culturable Vibrio Parahaemolyticus in Frozen Bivalve Molluscs

Authors: Eleonora Di Salvo, Antonio Panebianco, Graziella Ziino

Abstract:

Background: Vibrio parahaemolyticus is a human pathogen that is widely distributed in marine environments. It is frequently isolated from raw seafood, particularly shellfish. Consumption of raw or undercooked seafood contaminated with V. parahaemolyticus may lead to acute gastroenteritis. Vibrio spp. has excellent resistance to low temperatures so it can be found in frozen products for a long time. Recently, the viable but non-culturable state (VBNC) of bacteria has attracted great attention, and more than 85 species of bacteria have been demonstrated to be capable of entering this state. VBNC cells cannot grow in conventional culture medium but are viable and maintain metabolic activity, which may constitute an unrecognized source of food contamination and infection. Also V. parahaemolyticus could exist in VBNC state under nutrient starvation or low-temperature conditions. Aim: The aim of the present study was to optimize methods and investigate V. parahaemolyticus VBNC cells and their presence in frozen bivalve molluscs, regularly marketed. Materials and Methods: propidium monoazide (PMA) was integrated with real-time polymerase chain reaction (qPCR) targeting the tl gene to detect and quantify V. parahaemolyticus in the VBNC state. PMA-qPCR resulted highly specific to V. parahaemolyticus with a limit of detection (LOD) of 10-1 log CFU/mL in pure bacterial culture. A standard curve for V. parahaemolyticus cell concentrations was established with the correlation coefficient of 0.9999 at the linear range of 1.0 to 8.0 log CFU/mL. A total of 77 samples of frozen bivalve molluscs (35 mussels; 42 clams) were subsequently subjected to the qualitative (on alkaline phosphate buffer solution) and quantitative research of V. parahaemolyticus on thiosulfate-citrate-bile salts-sucrose (TCBS) agar (DIFCO) NaCl 2.5%, and incubation at 30°C for 24-48 hours. Real-time PCR was conducted on homogenate samples, in duplicate, with and without propidium monoazide (PMA) dye, and exposed for 45 min under halogen lights (650 W). Total DNA was extracted from cell suspension in homogenate samples according to bolliture protocol. The Real-time PCR was conducted with species-specific primers for V. parahaemolitycus. The RT-PCR was performed in a final volume of 20 µL, containing 10 µL of SYBR Green Mixture (Applied Biosystems), 2 µL of template DNA, 2 µL of each primer (final concentration 0.6 mM), and H2O 4 µL. The qPCR was carried out on CFX96 TouchTM (Bio-Rad, USA). Results: All samples were negative both to the quantitative and qualitative detection of V. parahaemolyticus by the classical culturing technique. The PMA-qPCR let us individuating VBNC V. parahaemolyticus in the 20,78% of the samples evaluated with a value between the Log 10-1 and Log 10-3 CFU/g. Only clams samples were positive for PMA-qPCR detection. Conclusion: The present research is the first evaluating PMA-qPCR assay for detection of VBNC V. parahaemolyticus in bivalve molluscs samples, and the used method was applicable to the rapid control of marketed bivalve molluscs. We strongly recommend to use of PMA-qPCR in order to identify VBNC forms, undetectable by the classic microbiological methods. A precise knowledge of the V.parahaemolyticus in a VBNC form is fundamental for the correct risk assessment not only in bivalve molluscs but also in other seafood.

Keywords: food safety, frozen bivalve molluscs, PMA dye, Real-time PCR, VBNC state, Vibrio parahaemolyticus

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