Search results for: prior and posterior distribution
Commenced in January 2007
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Edition: International
Paper Count: 6893

Search results for: prior and posterior distribution

5753 Optimization of Line Loss Minimization Using Distributed Generation

Authors: S. Sambath, P. Palanivel

Abstract:

Research conducted in the last few decades has proven that an inclusion of Distributed Genaration (DG) into distribution systems considerably lowers the level of power losses and the power quality improved. Moreover, the choice of DG is even more attractive since it provides not only benefits in power loss minimisation, but also a wide range of other advantages including environment, economic, power qualities and technical issues. This paper is an intent to quantify and analyse the impact of distributed generation (DG) in Tamil Nadu, India to examine what the benefits of decentralized generation would be for meeting rural loads. We used load flow analysis to simulate and quantify the loss reduction and power quality enhancement by having decentralized generation available line conditions for actual rural feeders in Tamil Nadu, India. Reactive and voltage profile was considered. This helps utilities to better plan their system in rural areas to meet dispersed loads, while optimizing the renewable and decentralised generation sources.

Keywords: distributed generation, distribution system, load flow analysis, optimal location, power quality

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5752 Assessment, Diagnosis and Treatment, Simulation for the Nurse Practitioner Student

Authors: Helen Coronel, Will Brewer, Peggy Bergeron, Clarissa Hall, Victoria Casson

Abstract:

Simulation-based training provides the nurse practitioner (NP) student with a safe and controlled environment in which they can practice a real-life scenario. This type of learning fosters critical thinking skills essential to practice. The expectation of this study was that students would have an increase in their competency and confidence after performing the simulation. Approximately 8.4% of Americans suffer from depression. The state of Alabama is ranked 47th out of 50 for access to mental health care. As a result of this significant shortage of mental health providers, primary care providers are frequently put in the position of screening for and treating mental health conditions, such as depression. Family nurse practitioners are often utilized as primary care providers, making their ability to assess, diagnose and treat these disorders a necessary skill. The expected outcome of this simulation is an increase in confidence, competency and the empowerment of the nurse practitioner student’s ability to assess, diagnose and treat a common mood disorder they may encounter in practice. The Kirkpatrick Module was applied for this study. A non-experimental design using descriptive statistical analysis was utilized. The simulation was based on a common psychiatric mood disorder frequently observed in primary care and mental health clinics. Students were asked to watch a voiceover power point presentation prior to their on-campus simulation. The presentation included training on the assessment, diagnosis, and treatment of a patient with depression. Prior to the simulation, the students completed a pre-test, then participated in the simulation, and completed a post-test when done. Apple iPads were utilized to access a simulated health record. Major findings of the study support an increase in students’ competency and confidence when assessing, diagnosing, and treating an adult patient with depression.

Keywords: advanced practice, nurse practitioner, simulation, primary care, depression

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5751 Multi-Objective Random Drift Particle Swarm Optimization Algorithm Based on RDPSO and Crowding Distance Sorting

Authors: Yiqiong Yuan, Jun Sun, Dongmei Zhou, Jianan Sun

Abstract:

In this paper, we presented a Multi-Objective Random Drift Particle Swarm Optimization algorithm (MORDPSO-CD) based on RDPSO and crowding distance sorting to improve the convergence and distribution with less computation cost. MORDPSO-CD makes the most of RDPSO to approach the true Pareto optimal solutions fast. We adopt the crowding distance sorting technique to update and maintain the archived optimal solutions. Introducing the crowding distance technique into MORDPSO can make the leader particles find the true Pareto solution ultimately. The simulation results reveal that the proposed algorithm has better convergence and distribution

Keywords: multi-objective optimization, random drift particle swarm optimization, crowding distance sorting, pareto optimal solution

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5750 A Two Tailed Secretary Problem with Multiple Criteria

Authors: Alaka Padhye, S. P. Kane

Abstract:

The following study considers some variations made to the secretary problem (SP). In a multiple criteria secretary problem (MCSP), the selection of a unit is based on two independent characteristics. The units that appear before an observer are known say N, the best rank of a unit being N. A unit is selected, if it is better with respect to either first or second or both the characteristics. When the number of units is large and due to constraints like time and cost, the observer might want to stop earlier instead of inspecting all the available units. Let the process terminate at r2th unit where r1Keywords: joint distribution, marginal distribution, real ranks, secretary problem, selection criterion, two tailed secretary problem

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5749 Critical Conditions for the Initiation of Dynamic Recrystallization Prediction: Analytical and Finite Element Modeling

Authors: Pierre Tize Mha, Mohammad Jahazi, Amèvi Togne, Olivier Pantalé

Abstract:

Large-size forged blocks made of medium carbon high-strength steels are extensively used in the automotive industry as dies for the production of bumpers and dashboards through the plastic injection process. The manufacturing process of the large blocks starts with ingot casting, followed by open die forging and a quench and temper heat treatment process to achieve the desired mechanical properties and numerical simulation is widely used nowadays to predict these properties before the experiment. But the temperature gradient inside the specimen remains challenging in the sense that the temperature before loading inside the material is not the same, but during the simulation, constant temperature is used to simulate the experiment because it is assumed that temperature is homogenized after some holding time. Therefore to be close to the experiment, real distribution of the temperature through the specimen is needed before the mechanical loading. Thus, We present here a robust algorithm that allows the calculation of the temperature gradient within the specimen, thus representing a real temperature distribution within the specimen before deformation. Indeed, most numerical simulations consider a uniform temperature gradient which is not really the case because the surface and core temperatures of the specimen are not identical. Another feature that influences the mechanical properties of the specimen is recrystallization which strongly depends on the deformation conditions and the type of deformation like Upsetting, Cogging...etc. Indeed, Upsetting and Cogging are the stages where the greatest deformations are observed, and a lot of microstructural phenomena can be observed, like recrystallization, which requires in-depth characterization. Complete dynamic recrystallization plays an important role in the final grain size during the process and therefore helps to increase the mechanical properties of the final product. Thus, the identification of the conditions for the initiation of dynamic recrystallization is still relevant. Also, the temperature distribution within the sample and strain rate influence the recrystallization initiation. So the development of a technique allowing to predict the initiation of this recrystallization remains challenging. In this perspective, we propose here, in addition to the algorithm allowing to get the temperature distribution before the loading stage, an analytical model leading to determine the initiation of this recrystallization. These two techniques are implemented into the Abaqus finite element software via the UAMP and VUHARD subroutines for comparison with a simulation where an isothermal temperature is imposed. The Artificial Neural Network (ANN) model to describe the plastic behavior of the material is also implemented via the VUHARD subroutine. From the simulation, the temperature distribution inside the material and recrystallization initiation is properly predicted and compared to the literature models.

Keywords: dynamic recrystallization, finite element modeling, artificial neural network, numerical implementation

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5748 Testicular Dose and Associated Risk from Common Pelvis Radiation Therapy in Iran

Authors: Ahmad Shanei, Milad Baradaran-Ghahfarokhi

Abstract:

This study aimed to investigate testicular dose (TD) and the associated risk of heritable disease from common pelvis radiotherapy of male patients in Iran. In this work, the relation between TD and changes in beam energy, pelvis size, source to skin distance (SSD) and beam directions (anterior or posterior) were also evaluated. The values of TDs were measured on 67 randomly selected male patients during common pelvis radiotherapy using 1.17 and 1.33 MeV, Theratron Cobalt-60 unit at SSD of 80 cm and 9 MV, Neptun 10 PC and 18 MV, GE Saturne 20 at SSD of 100 cm at Seyed-Al Shohada Hospital, Isfahan, Iran. Results showed that the maximum TD was up to 12% of the tumor dose. Considering the risk factor for radiation-induced heritable disorders of 0.1% per Sv, an excess risk of hereditary disorders of 72 per 10000 births was conservatively calculated. There was a significant difference in the measured TD using different treatment machines and energies (P < 0.001). The TD at 100 cm SSD were much less than that for 80 cm SSD (P <0.001). The Pearson Correlation test showed that, as expected, there was a strong correlation between TD and patient’s pelvis size (r = 0.275, P <0.001). Using the student’s t-tests, it was found that, there was not a significant difference between TD and beam direction (P = 0.231). Iranian male patients undergoing pelvic radiotherapy have the potential of receiving a TD of more than 1 Gy which might result in temporary azoospermia. The risk for induction of hereditary disorders in future generations should be considered as low but not negligible in comparison with the correspondent nominal risk.

Keywords: pelvis radiotherapy, testicular dose, infertility, hereditary effects

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5747 A Periodogram-Based Spectral Method Approach: The Relationship between Tourism and Economic Growth in Turkey

Authors: Mesut BALIBEY, Serpil TÜRKYILMAZ

Abstract:

A popular topic in the econometrics and time series area is the cointegrating relationships among the components of a nonstationary time series. Engle and Granger’s least squares method and Johansen’s conditional maximum likelihood method are the most widely-used methods to determine the relationships among variables. Furthermore, a method proposed to test a unit root based on the periodogram ordinates has certain advantages over conventional tests. Periodograms can be calculated without any model specification and the exact distribution under the assumption of a unit root is obtained. For higher order processes the distribution remains the same asymptotically. In this study, in order to indicate advantages over conventional test of periodograms, we are going to examine a possible relationship between tourism and economic growth during the period 1999:01-2010:12 for Turkey by using periodogram method, Johansen’s conditional maximum likelihood method, Engle and Granger’s ordinary least square method.

Keywords: cointegration, economic growth, periodogram ordinate, tourism

Procedia PDF Downloads 270
5746 Sliding Mode Control and Its Application in Custom Power Device: A Comprehensive Overview

Authors: Pankaj Negi

Abstract:

Nowadays the demand for receiving the high quality electrical energy is being increasing as consumer wants not only reliable but also quality power. Custom power instruments are of the most well-known compensators of power quality in distributed network. This paper present a comprehensive review of compensating custom power devices mainly DSTATCOM (distribution static compensator),DVR (dynamic voltage restorer), and UPQC (unified power quality compensator) and also deals with sliding mode control and its applications to custom power devices. The sliding mode control strategy provides robustness to custom power device and enhances the dynamic response for compensating voltage sag, swell, voltage flicker, and voltage harmonics. The aim of this paper is to provide a broad perspective on the status of compensating devices in electric power distribution system and sliding mode control strategies to researchers and application engineers who are dealing with power quality and stability issues.

Keywords: active power filters(APF), custom power device(CPD), DSTATCOM, DVR, UPQC, sliding mode control (SMC), power quality

Procedia PDF Downloads 439
5745 Design of Impedance Box to Study Fluid Parameters

Authors: K. AlJimaz, A. Abdullah, A. Abdulsalam, K. Ebdah, A. Abdalrasheed

Abstract:

Understanding flow distribution and head losses is essential to design and calculate Thermo fluid parameters in order to reduce the pressure to a certain required pressure. This paper discusses the ways acquired in design and simulation to create and design an impedance box that reduces pressure. It's controlled by specific scientific principles such as Bernoulli’s principle and conservation of mass. In this paper, the design is made using SOLIDWORKS, and the simulation is done using ANSYS software to solve differential equations and study the parameters in the 3D model, also to understand how the design of this box reduced the pressure. The design was made so that fluid enters at a certain pressure of 3000 Pa in a single inlet; then, it exits from six outlets at a pressure of 300 Pa with respect to the conservation of mass principle. The effect of the distribution of flow and the head losses has been noticed that it has an impact on reducing the pressure since other factors, such as friction, were neglected and also the temperature, which was constant. The design showed that the increase in length and diameter of the pipe helped to reduce the pressure, and the head losses contributed significantly to reduce the pressure to 10% of the original pressure (from 3000 Pa to 300 Pa) at the outlets.

Keywords: box, pressure, thermodynamics, 3D

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5744 CT Images Based Dense Facial Soft Tissue Thickness Measurement by Open-source Tools in Chinese Population

Authors: Ye Xue, Zhenhua Deng

Abstract:

Objectives: Facial soft tissue thickness (FSTT) data could be obtained from CT scans by measuring the face-to-skull distances at sparsely distributed anatomical landmarks by manually located on face and skull. However, automated measurement using 3D facial and skull models by dense points using open-source software has become a viable option due to the development of computed assisted imaging technologies. By utilizing dense FSTT information, it becomes feasible to generate plausible automated facial approximations. Therefore, establishing a comprehensive and detailed, densely calculated FSTT database is crucial in enhancing the accuracy of facial approximation. Materials and methods: This study utilized head CT scans from 250 Chinese adults of Han ethnicity, with 170 participants originally born and residing in northern China and 80 participants in southern China. The age of the participants ranged from 14 to 82 years, and all samples were divided into five non-overlapping age groups. Additionally, samples were also divided into three categories based on BMI information. The 3D Slicer software was utilized to segment bone and soft tissue based on different Hounsfield Unit (HU) thresholds, and surface models of the face and skull were reconstructed for all samples from CT data. Following procedures were performed unsing MeshLab, including converting the face models into hollowed cropped surface models amd automatically measuring the Hausdorff Distance (referred to as FSTT) between the skull and face models. Hausdorff point clouds were colorized based on depth value and exported as PLY files. A histogram of the depth distributions could be view and subdivided into smaller increments. All PLY files were visualized of Hausdorff distance value of each vertex. Basic descriptive statistics (i.e., mean, maximum, minimum and standard deviation etc.) and distribution of FSTT were analysis considering the sex, age, BMI and birthplace. Statistical methods employed included Multiple Regression Analysis, ANOVA, principal component analysis (PCA). Results: The distribution of FSTT is mainly influenced by BMI and sex, as further supported by the results of the PCA analysis. Additionally, FSTT values exceeding 30mm were found to be more sensitive to sex. Birthplace-related differences were observed in regions such as the forehead, orbital, mandibular, and zygoma. Specifically, there are distribution variances in the depth range of 20-30mm, particularly in the mandibular region. Northern males exhibit thinner FSTT in the frontal region of the forehead compared to southern males, while females shows fewer distribution differences between the northern and southern, except for the zygoma region. The observed distribution variance in the orbital region could be attributed to differences in orbital size and shape. Discussion: This study provides a database of Chinese individuals distribution of FSTT and suggested opening source tool shows fine function for FSTT measurement. By incorporating birthplace as an influential factor in the distribution of FSTT, a greater level of detail can be achieved in facial approximation.

Keywords: forensic anthropology, forensic imaging, cranial facial reconstruction, facial soft tissue thickness, CT, open-source tool

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5743 Characterization of Nanoemulsion Incorporating Crude Cocoa Polyphenol

Authors: Suzannah Sharif, Aznie Aida Ahmad, Maznah Ismail

Abstract:

Cocoa bean is the raw material for products such as cocoa powder and chocolate. Cocoa bean contains polyphenol which has been shown in several clinical studies to confer beneficial health effects. However studies showed that cocoa polyphenol absorption in the human intestinal tracts are very low. Therefore nanoemulsion may be one way to increase the bioavailability of cocoa polyphenol. This study aim to characterize nanoemulsion incorporating crude cocoa polyphenol produced using high energy technique. Cocoa polyphenol was extracted from fresh freeze-dried cocoa beans from Malaysia. The particle distribution, particle size, and zeta potential were determined. The emulsion was also analysed using transmission electron microscope to visualize the particles. Solubilization study was conducted by titrating the nanoemulsion into distilled water or 1% surfactant solution. Result showed that the nanoemulsion contains particle which have narrow size distribution. The particles size average at 112nm with zeta potential of -45mV. The nanoemulsions behave differently in distilled water and surfactant solution.

Keywords: cocoa, nanoemulsion, cocoa polyphenol, solubilisation study

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5742 Regional Disparities in Microfinance Distribution: Evidence from Indian States

Authors: Sunil Sangwan, Narayan Chandra Nayak

Abstract:

Over the last few decades, Indian banking system has achieved remarkable growth in its credit volume. However, one of the most disturbing facts about this growth is the uneven distribution of financial services across regions. Having witnessed limited success from all the earlier efforts towards financial inclusion targeting the rural poor and the underprivileged, provision of microfinance, of late, has emerged as a supplementary mechanism. There are two prominent modes of microfinance distribution in India namely Bank-SHG linkage (SBLP) and private Microfinance Institutions (MFIs). Ironically, such efforts also seem to have failed to achieve the desired targets as the microfinance services have witnessed skewed distribution across the states of the country. This study attempts to make a comparative analysis of the geographical skew of the SBLP and MFI in India and examine the factors influencing their regional distribution. The results indicate that microfinance services are largely concentrated in the southern region, accounting for about 50% of all microfinance clients and 49% of all microfinance loan portfolios. This is distantly followed by an eastern region where client outreach is close to 25% only. The north-eastern, northern, central, and western regions lag far behind in microfinance sectors, accounting for only 4%, 4%, 10%, and 7 % client outreach respectively. The penetration of SHGs is equally skewed, with the southern region accounting for 46% of client outreach and 70% of loan portfolios followed by an eastern region with 21% of client outreach and 13% of the loan portfolio. Contrarily, north-eastern, northern, central, western and eastern regions account for 5%, 5%, 10%, and 13% of client outreach and 3%, 3%, 7%, and 4% of loan portfolios respectively. The study examines the impact of literacy rate, rural poverty, population density, primary sector share, non-farm activities, loan default behavior and bank penetration on the microfinance penetration. The study is limited to 17 major states of the country over the period 2008-2014. The results of the GMM estimation indicate the significant positive impact of literacy rate, non-farm activities and population density on microfinance penetration across the states, while the rise in loan default seems to deter it. Rural poverty shows the significant negative impact on the spread of SBLP, while it has a positive impact on MFI penetration, hence indicating the policy of exclusion being adhered to by the formal financial system especially towards the poor. However, MFIs seem to be working as substitute mechanisms to banks to fill the gap. The findings of the study are a pointer towards enhancing financial literacy, non-farm activities, rural bank penetration and containing loan default for achieving greater microfinance prevalence.

Keywords: bank penetration, literacy rate, microfinance, primary sector share, rural non-farm activities, rural poverty

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5741 Effect of Core Puncture Diameter on Bio-Char Kiln Efficiency

Authors: W. Intagun, T. Khamdaeng, P. Prom-ngarm, N. Panyoyai

Abstract:

Biochar has been used as a soil amendment since it has high porous structure and has proper nutrients and chemical properties for plants. Product yields produced from biochar kiln are dependent on process parameters and kiln types used. The objective of this research is to investigate the effect of core puncture diameter on biochar kiln efficiency, i.e., yields of biochar and produced gas. Corncobs were used as raw material to produce biochar. Briquettes from agricultural wastes were used as fuel. Each treatment was performed by changing the core puncture diameter. From the experiment, it is revealed that the yield of biochar at the core puncture diameter of 3.18 mm, 4.76 mm, and 6.35 mm was 10.62 wt. %, 24.12 wt. %, and 12.24 wt. %, of total solid yields, respectively. The yield of produced gas increased with increasing the core puncture diameter. The maximum percentage by weight of the yield of produced gas was 81.53 wt. % which was found at the core puncture diameter of 6.35 mm. The core puncture diameter was furthermore found to affect the temperature distribution inside the kiln and its thermal efficiency. In conclusion, the high efficient biochar kiln can be designed and constructed by using the proper core puncture diameter.

Keywords: anila stove, bio-char, soil conditioning materials, temperature distribution

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5740 Model of Transhipment and Routing Applied to the Cargo Sector in Small and Medium Enterprises of Bogotá, Colombia

Authors: Oscar Javier Herrera Ochoa, Ivan Dario Romero Fonseca

Abstract:

This paper presents a design of a model for planning the distribution logistics operation. The significance of this work relies on the applicability of this fact to the analysis of small and medium enterprises (SMEs) of dry freight in Bogotá. Two stages constitute this implementation: the first one is the place where optimal planning is achieved through a hybrid model developed with mixed integer programming, which considers the transhipment operation based on a combined load allocation model as a classic transshipment model; the second one is the specific routing of that operation through the heuristics of Clark and Wright. As a result, an integral model is obtained to carry out the step by step planning of the distribution of dry freight for SMEs in Bogotá. In this manner, optimum assignments are established by utilizing transshipment centers with that purpose of determining the specific routing based on the shortest distance traveled.

Keywords: transshipment model, mixed integer programming, saving algorithm, dry freight transportation

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5739 Human Leukocyte Antigen Class 1 Phenotype Distribution and Analysis in Persons from Central Uganda with Active Tuberculosis and Latent Mycobacterium tuberculosis Infection

Authors: Helen K. Buteme, Rebecca Axelsson-Robertson, Moses L. Joloba, Henry W. Boom, Gunilla Kallenius, Markus Maeurer

Abstract:

Background: The Ugandan population is heavily affected by infectious diseases and Human leukocyte antigen (HLA) diversity plays a crucial role in the host-pathogen interaction and affects the rates of disease acquisition and outcome. The identification of HLA class 1 alleles and determining which alleles are associated with tuberculosis (TB) outcomes would help in screening individuals in TB endemic areas for susceptibility to TB and to predict resistance or progression to TB which would inevitably lead to better clinical management of TB. Aims: To be able to determine the HLA class 1 phenotype distribution in a Ugandan TB cohort and to establish the relationship between these phenotypes and active and latent TB. Methods: Blood samples were drawn from 32 HIV negative individuals with active TB and 45 HIV negative individuals with latent MTB infection. DNA was extracted from the blood samples and the DNA samples HLA typed by the polymerase chain reaction-sequence specific primer method. The allelic frequencies were determined by direct count. Results: HLA-A*02, A*01, A*74, A*30, B*15, B*58, C*07, C*03 and C*04 were the dominant phenotypes in this Ugandan cohort. There were differences in the distribution of HLA types between the individuals with active TB and the individuals with LTBI with only HLA-A*03 allele showing a statistically significant difference (p=0.0136). However, after FDR computation the corresponding q-value is above the expected proportion of false discoveries (q-value 0.2176). Key findings: We identified a number of HLA class I alleles in a population from Central Uganda which will enable us to carry out a functional characterization of CD8+ T-cell mediated immune responses to MTB. Our results also suggest that there may be a positive association between the HLA-A*03 allele and TB implying that individuals with the HLA-A*03 allele are at a higher risk of developing active TB.

Keywords: HLA, phenotype, tuberculosis, Uganda

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5738 Associations of Vitamin D Receptor Polymorphisms with Coronary Artery Diseases

Authors: Elham Sharif, Nasser Rizk, Sirin Abu Aqel, Ofelia Masoud

Abstract:

Background: Previous studies have investigated the association of rs1544410, rs7975232 and rs731236 polymorphisms in vitamin D receptor gene and its impact on diseases such as cancer, diabetes and hypertension in different ethnic backgrounds. Aim: The aim of this study is to investigate the association between VDR polymorphisms using three SNP’s (rs1544410, rs7975232 and rs731236) and the severity of the significant lesion in coronary arteries among angiographically diagnosed CAD. Methods: A prospective-retrospective study was conducted on 192 CAD patients enrolled from the cardiology department-Heart Hospital HMC, grouped in 96 subjects with significant stenosis and 96 with non-significant stenosis with a mean age between 30 and 75 years old. Genotyping was performed for the following SNPs rs1544410, rs7975232 and rs731236 using TaqMan assay by the Real Time PCR, ABI 7500 in Health Sciences Labs at Qatar University Biomedical Research Center. Results: The results showed that both groups have matched age and gender distribution but patients with the significant stenosis have significantly higher; BMI (p=0.047); smoking status (p=0.039); FBS (p= 0.031); CK-MB (p=0.025) and Troponin (p=0.002) than the patients with non–significant lesion. Among the traditional risk factors, smoking increases the odds of the severe stenotic lesion in CAD patients by 1.984, with 95% CI between 1.024 – 7.063, with p= 0.042.HWE showed deviations of the rs1544410 and rs731236 among the study subjects. The most frequent genotype in distribution of rs7975232 is the AA among the significant stenosis patients, while the heterozygous AC was the frequent genotype in distribution among the non-significant stenosis group. The carriers of CC genotype in rs7975232 increased the risk of having significant coronary arteries stenotic lesion by 1.83 with 95% CI (1.020 – 3.280), p=0.043. No association was found between the rs7975232 with vitamin D and VDBP. Conclusion: There is a significant association between rs7975232 and the severity of CAD lesion. The carrier of CC genotype in rs7975232 increased the risk of having significant coronary arteries atherosclerotic lesion especially in patients with smoking history independent of vitamin D.

Keywords: vitamin D, vitamin D receptor, polymorphism, coronary harat disease

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5737 EEG Analysis of Brain Dynamics in Children with Language Disorders

Authors: Hamed Alizadeh Dashagholi, Hossein Yousefi-Banaem, Mina Naeimi

Abstract:

Current study established for EEG signal analysis in patients with language disorder. Language disorder can be defined as meaningful delay in the use or understanding of spoken or written language. The disorder can include the content or meaning of language, its form, or its use. Here we applied Z-score, power spectrum, and coherence methods to discriminate the language disorder data from healthy ones. Power spectrum of each channel in alpha, beta, gamma, delta, and theta frequency bands was measured. In addition, intra hemispheric Z-score obtained by scoring algorithm. Obtained results showed high Z-score and power spectrum in posterior regions. Therefore, we can conclude that peoples with language disorder have high brain activity in frontal region of brain in comparison with healthy peoples. Results showed that high coherence correlates with irregularities in the ERP and is often found during complex task, whereas low coherence is often found in pathological conditions. The results of the Z-score analysis of the brain dynamics showed higher Z-score peak frequency in delta, theta and beta sub bands of Language Disorder patients. In this analysis there were activity signs in both hemispheres and the left-dominant hemisphere was more active than the right.

Keywords: EEG, electroencephalography, coherence methods, language disorder, power spectrum, z-score

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5736 Reducing Uncertainty of Monte Carlo Estimated Fatigue Damage in Offshore Wind Turbines Using FORM

Authors: Jan-Tore H. Horn, Jørgen Juncher Jensen

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Uncertainties related to fatigue damage estimation of non-linear systems are highly dependent on the tail behaviour and extreme values of the stress range distribution. By using a combination of the First Order Reliability Method (FORM) and Monte Carlo simulations (MCS), the accuracy of the fatigue estimations may be improved for the same computational efforts. The method is applied to a bottom-fixed, monopile-supported large offshore wind turbine, which is a non-linear and dynamically sensitive system. Different curve fitting techniques to the fatigue damage distribution have been used depending on the sea-state dependent response characteristics, and the effect of a bi-linear S-N curve is discussed. Finally, analyses are performed on several environmental conditions to investigate the long-term applicability of this multistep method. Wave loads are calculated using state-of-the-art theory, while wind loads are applied with a simplified model based on rotor thrust coefficients.

Keywords: fatigue damage, FORM, monopile, Monte Carlo, simulation, wind turbine

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5735 Waters Colloidal Phase Extraction and Preconcentration: Method Comparison

Authors: Emmanuelle Maria, Pierre Crançon, Gaëtane Lespes

Abstract:

Colloids are ubiquitous in the environment and are known to play a major role in enhancing the transport of trace elements, thus being an important vector for contaminants dispersion. Colloids study and characterization are necessary to improve our understanding of the fate of pollutants in the environment. However, in stream water and groundwater, colloids are often very poorly concentrated. It is therefore necessary to pre-concentrate colloids in order to get enough material for analysis, while preserving their initial structure. Many techniques are used to extract and/or pre-concentrate the colloidal phase from bulk aqueous phase, but yet there is neither reference method nor estimation of the impact of these different techniques on the colloids structure, as well as the bias introduced by the separation method. In the present work, we have tested and compared several methods of colloidal phase extraction/pre-concentration, and their impact on colloids properties, particularly their size distribution and their elementary composition. Ultrafiltration methods (frontal, tangential and centrifugal) have been considered since they are widely used for the extraction of colloids in natural waters. To compare these methods, a ‘synthetic groundwater’ was used as a reference. The size distribution (obtained by Field-Flow Fractionation (FFF)) and the chemical composition of the colloidal phase (obtained by Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Total Organic Carbon analysis (TOC)) were chosen as comparison factors. In this way, it is possible to estimate the pre-concentration impact on the colloidal phase preservation. It appears that some of these methods preserve in a more efficient manner the colloidal phase composition while others are easier/faster to use. The choice of the extraction/pre-concentration method is therefore a compromise between efficiency (including speed and ease of use) and impact on the structural and chemical composition of the colloidal phase. In perspective, the use of these methods should enhance the consideration of colloidal phase in the transport of pollutants in environmental assessment studies and forensics.

Keywords: chemical composition, colloids, extraction, preconcentration methods, size distribution

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5734 The Distribution of HLA-B*15:01 and HLA-B*51:01 Alleles in Thai Population: Clinical Implementation and Diagnostic Process of COVID-19 Severity

Authors: Aleena Rena Onozuka, Patompong Satapornpong

Abstract:

Introduction: In a Human Leukocyte Antigen (HLA)’s immune response, HLA alleles (HLA class I and class II) play a crucial role in fighting against pathogens. HLA-B*15:01 allele had a significant association with asymptomatic COVID-19 infection (p-value = 5.67 x 10-5 ; OR = 2.40 and 95% CI = 1.54 - 3.64). There was also a notable linkage between HLA-B*51:01 allele and critically ill patients with COVID-19 (p-value = 0.007 and OR = 3.38). This study has described the distribution of HLA marker alleles in Thais and sub-groups. Objective: We want to investigate the prevalence of HLA-B*15:01 and HLA-B*51:01 alleles in the Thai population. Materials and Methods: 200 healthy Thai population were included in this study from the College of Pharmacy, Rangsit University. HLA-B alleles were genotyped using the sequence-specific oligonucleotides process (PCR-SSOs). Results: We found out that HLA-B*46:01 (12.00%), HLA-B*15:02 (9.25%), HLA-B*40:01 (6.50%), HLA-B*13:01 (6.25%), and HLA-B* 38:02 (5.50%) alleles were more common than other alleles in Thai population. HLA-B*46:01 and HLA-B*15:02 were the most common allele found across four regions. Moreover, the frequency of HLA-B*15:01 and HLA-B*51:01 alleles were similarly distributed in Thai population (0.50, 5.25 %) and (p-value > 0.05), respectively. The frequencies of HLA-B*15:01 and HLA-B*51:01 alleles were not significantly different from other populations compared to the Thai population. Conclusions: We can screen for HLA-B*15:01 and HLA-B*51:01 alleles to determine the symptoms of COVID-19 since they are universal HLA-B markers. Importantly, the database of HLA markers indicates the association between HLA frequency and populations. However, we need further research on larger numbers of COVID-19 patients and in different populations.

Keywords: HLA-B*15:01, HLA-B*51:01, COVID-19, HLA-B alleles

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5733 A Methodology for Seismic Performance Enhancement of RC Structures Equipped with Friction Energy Dissipation Devices

Authors: Neda Nabid

Abstract:

Friction-based supplemental devices have been extensively used for seismic protection and strengthening of structures, however, the conventional use of these dampers may not necessarily lead to an efficient structural performance. Conventionally designed friction dampers follow a uniform height-wise distribution pattern of slip load values for more practical simplicity. This can lead to localizing structural damage in certain story levels, while the other stories accommodate a negligible amount of relative displacement demand. A practical performance-based optimization methodology is developed to tackle with structural damage localization of RC frame buildings with friction energy dissipation devices under severe earthquakes. The proposed methodology is based on the concept of uniform damage distribution theory. According to this theory, the slip load values of the friction dampers redistribute and shift from stories with lower relative displacement demand to the stories with higher inter-story drifts to narrow down the discrepancy between the structural damage levels in different stories. In this study, the efficacy of the proposed design methodology is evaluated through the seismic performance of five different low to high-rise RC frames equipped with friction wall dampers under six real spectrum-compatible design earthquakes. The results indicate that compared to the conventional design, using the suggested methodology to design friction wall systems can lead to, by average, up to 40% reduction of maximum inter-story drift; and incredibly more uniform height-wise distribution of relative displacement demands under the design earthquakes.

Keywords: friction damper, nonlinear dynamic analysis, RC structures, seismic performance, structural damage

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5732 The Effectiveness of Men Who Have Sex with Men (MSM) Sensitivity Training for Nigerian Health Care Providers (HCPs)

Authors: Chiedu C. Ifekandu, Olusegun Sangowawa, Jean E. Njab

Abstract:

Background: Health care providers (HCPs) in Nigeria receive little or no training of the healthcare needs of men who have sex with men (MSM) limiting the quality and effectiveness of comprehensive HIV prevention and treatment services. Consequently, most MSM disguise themselves to access services which limit the quality of care provided partly due to challenges related to stigma and discrimination, and breach of confidentiality. Objective: To assess the knowledge of healthcare providers on effective intervention for MSM. Methods: We trained 122 HIV focal persons drawn from 60 health facilities from twelve Nigerian states. , the participants were requested to complete a pre-training questionnaire to assess their level of working experience with key populations as a baseline. Participants included male and female doctors, nurses and counselors/testers. A test was administered to measure their knowledge on MSM sexual risk practices, HIV prevention and healthcare needs and also to assess their attitudes (including homophobia) and beliefs and how it affects service uptake by key populations particularly MSM prior and immediately after the training to ascertain the impact of the training. Results: The mean age of the HCP was 38 years +/- SD Of the 122 HCPs (45 % female, 55 % male; 85 % counsellor/testers; 15 % doctors and nurses; 92 % working in government facilities) from 42 health facilities were trained, of which 105 attempted the test questions. At the baseline, few HCPs reported any prior sensitivity training on MSM. Most of the HCPs had limited knowledge of MSM sexual health needs. Over 90% of the HCPs believed that homosexuality is a mental illness. 8 % do not consider MSM, FSW and PWID as key populations for HIV infection. 45 % lacked knowledge on MSM anal sexual practices. The post-test showed that homophobic attitudes had decreased significantly by the end of the training; the health care providers have acquired basic knowledge compared to the pre-test. Conclusions: Scaling up MSM sensitivity training for Nigerian HCPs is likely to be a timely and effective means to improve their understanding of MSM-related health issues, reduce homophobic sentiments and enhance their capacity to provide responsive HIV prevention, treatment and care services in a supportive and non-stigmatizing environment.

Keywords: healthcare providers, key population, men who have sex with men, HCT

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5731 Investigating a Deterrence Function for Work Trips for Perth Metropolitan Area

Authors: Ali Raouli, Amin Chegenizadeh, Hamid Nikraz

Abstract:

The Perth metropolitan area and its surrounding regions have been expanding rapidly in recent decades and it is expected that this growth will continue in the years to come. With this rapid growth and the resulting increase in population, consideration should be given to strategic planning and modelling for the future expansion of Perth. The accurate estimation of projected traffic volumes has always been a major concern for the transport modelers and planners. Development of a reliable strategic transport model depends significantly on the inputs data into the model and the calibrated parameters of the model to reflect the existing situation. Trip distribution is the second step in four-step modelling (FSM) which is complex due to its behavioral nature. Gravity model is the most common method for trip distribution. The spatial separation between the Origin and Destination (OD) zones will be reflected in gravity model by applying deterrence functions which provide an opportunity to include people’s behavior in choosing their destinations based on distance, time and cost of their journeys. Deterrence functions play an important role for distribution of the trips within a study area and would simulate the trip distances and therefore should be calibrated for any particular strategic transport model to correctly reflect the trip behavior within the modelling area. This paper aims to review the most common deterrence functions and propose a calibrated deterrence function for work trips within the Perth Metropolitan Area based on the information obtained from the latest available Household data and Perth and Region Travel Survey (PARTS) data. As part of this study, a four-step transport model using EMME software has been developed for Perth Metropolitan Area to assist with the analysis and findings.

Keywords: deterrence function, four-step modelling, origin destination, transport model

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5730 Understanding the Factors Influencing Urban Ethiopian Consumers’ Consumption Intention of Spirulina-Supplemented Bread

Authors: Adino Andaregie, Isao Takagi, Hirohisa Shimura, Mitsuko Chikasada, Shinjiro Sato, Solomon Addisu

Abstract:

Context: The prevalence of undernutrition in developing countries like Ethiopia has become a significant issue. In this regard, finding alternative nutritional supplements seems to be a practical solution. Spirulina, a highly nutritious microalgae, offers a valuable option as it is a rich source of various essential nutrients. The study aimed to establish the factors affecting urban Ethiopian consumers' consumption intention of Spirulina-fortified bread. Research Aim: The primary purpose of this research is to identify the behavioral and socioeconomic factors impacting the intention of urban Ethiopian consumers to eat Spirulina-fortified bread. Methodology: The research utilized a quantitative approach wherein a structured questionnaire was created and distributed among 361 urban consumers via an online platform. The theory of planned behavior (TPB) was used as a conceptual framework, and confirmatory factor analysis (CFA) and structural equation modelling (SEM) were employed for data analysis. Findings: The study results revealed that attitude towards the supplement, subjective norms, and perceived behavioral control were the critical factors influencing the consumption intention of Spirulina-fortified bread. Moreover, age, physical exercise, and prior knowledge of Spirulina as a food ingredient were also found to have a significant influence. Theoretical Importance: The study contributes towards the understanding of consumer behavior and factors affecting the purchase intentions of Spirulina-fortified bread in urban Ethiopia. The use of TPB as a theoretical framework adds a vital aspect to the study as it provides helpful insights into the factors affecting intentions towards this functional food. Data Collection and Analysis Procedures: The data collection process involved the creation of a structured questionnaire, which was distributed online to urban Ethiopian consumers. Once data was collected, CFA and SEM were utilized to analyze the data and identify the factors impacting consumer behavior. Questions Addressed: The study aimed to address the following questions: (1) What are the behavioral and socioeconomic factors impacting urban Ethiopian consumers' consumption intention of Spirulina-fortified bread? (2) To what extent do attitude towards the supplement, subjective norms, and perceived behavioral control affect the purchase intention of Spirulina-fortified bread? (3) What role does age, education, income, physical exercise, and prior knowledge of Spirulina as a food ingredient play in the purchase intention of Spirulina-fortified bread among urban Ethiopian consumers? Conclusion: The study concludes that attitude towards the supplement, subjective norms, and perceived behavioral control are significant factors influencing urban Ethiopian consumers’ consumption intention of Spirulina-fortified bread. Moreover, age, education, income, physical exercise, and prior knowledge of Spirulina as a food ingredient also play a significant role in determining purchase intentions. The findings provide valuable insights for developing effective marketing strategies for Spirulina-fortified functional foods targeted at different consumer segments.

Keywords: spirulina, consumption, factors, intention, consumers, behavior

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5729 Saline Aspiration Negative Intravascular Test: Mitigating Risk with Injectable Fillers

Authors: Marcelo Lopes Dias Kolling, Felipe Ferreira Laranjeira, Guilherme Augusto Hettwer, Pedro Salomão Piccinini, Marwan Masri, Carlos Oscar Uebel

Abstract:

Introduction: Injectable fillers are among the most common nonsurgical cosmetic procedures, with significant growth yearly. Knowledge of rheological and mechanical characteristics of fillers, facial anatomy, and injection technique is essential for safety. Concepts such as the use of cannula versus needle, aspiration before injection, and facial danger zones have been well discussed. In case of an accidental intravascular puncture, the pressure inside the vessel may not be sufficient to push blood into the syringe due to the characteristics of the filler product; this is especially true for calcium hydroxyapatite (CaHA) or hyaluronic acid (HA) fillers with high G’. Since viscoelastic properties of normal saline are much lower than those of fillers, aspiration with saline prior to filler injection may decrease the risk of a false negative aspiration and subsequent catastrophic effects. We discuss a technique to add an additional safety step to the procedure with saline aspiration prior to injection, a ‘’reverse Seldinger’’ technique for intravascular access, which we term SANIT: Saline Aspiration Negative Intravascular Test. Objectives: To demonstrate the author’s (PSP) technique which adds an additional safety step to the process of filler injection, with both CaHA and HA, in order to decrease the risk of intravascular injection. Materials and Methods: Normal skin cleansing and topical anesthesia with prilocaine/lidocaine cream are performed; the facial subunits to be treated are marked. A 3mL Luer lock syringe is filled with 2mL of 0.9% normal saline and a 27G needle, which is turned one half rotation. When a cannula is to be used, the Luer lock syringe is attached to a 27G 4cm single hole disposable cannula. After skin puncture, the 3mL syringe is advanced with the plunger pulled back (negative pressure). Progress is made to the desired depth, all the while aspirating. Once the desired location of filler injection is reached, the syringe is exchanged for the syringe containing a filler, securely grabbing the hub of the needle and taking care to not dislodge the needle tip. Prior to this, we remove 0.1mL of filler to allow for space inside the syringe for aspiration. We again aspirate and inject retrograde. SANIT is especially useful for CaHA, since the G’ is much higher than HA, and thus reflux of blood into the syringe is less likely to occur. Results: The technique has been used safely for the past two years with no adverse events; the increase in cost is negligible (only the cost of 2mL of normal saline). Over 100 patients (over 300 syringes) have been treated with this technique. The risk of accidental intravascular puncture has been calculated to be between 1:6410 to 1:40882 syringes among expert injectors; however, the consequences of intravascular injection can be catastrophic even with board-certified physicians. Conclusions: While the risk of intravascular filler injection is low, the consequences can be disastrous. We believe that adding the SANIT technique can help further mitigate risk with no significant untoward effects and could be considered by all performing injectable fillers. Further follow-up is ongoing.

Keywords: injectable fillers, safety, saline aspiration, injectable filler complications, hyaluronic acid, calcium hydroxyapatite

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5728 Macrobenthic Fauna in the Intertidal Zone of Carmen, Agusan Del Norte

Authors: Maricris I. Abuan

Abstract:

This assessment of macrobenthic fauna found in the intertidal zone of Brgy. Poblacion, Carmen Agusan del Norte was conducted during the lowest tides of the month of June 2008. Transect-quadrat method was employed during the sampling. Twenty-transect lines were established in the area with lengths depending on the topography of the intertidal zone and were laid perpendicular to the shore, at intervals of fifty meters. Twenty-six (26) macrobenthic species with a total of seventy (70) individuals were identified in the study area. These species belong to the four Phyla -Arthropoda, Mollusca, Echinodermata and Annelida. The three most abundant macrobenthos were hermit crabs (Phylum Arthropoda) , Archaster typicus (Phylum Echinodermata), and Nassarius pullus (Phylum Mollusca). The diversity index value was 2.36. Most species exhibited random distribution And only few species had regular and clumped distribution. The pH, salinity, and sea water temperature readings were within the normal range. Results showed a very scarce macrobenthic species present in the study area.

Keywords: diversity index, macrobenthic fauna, macrobenthos, phyla

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5727 Self-Disclosure and Privacy Management Behavior in Social Media: Privacy Calculus Perspective

Authors: Chien-Wen Chen, Nguyen Duong Thuy Trang, Yu-Hsuan Chang

Abstract:

With the development of information technology, social networking sites are inseparable from life and have become an important way for people to communicate. Nonetheless, privacy issues are raised by the presence of personal information on social networking sites. However, users can benefit from using the functions of social networking sites, which also leads to users worrying about the leakage of personal information without corresponding privacy protection behaviors, which is called the privacy paradox. However, previous studies have questioned the viewpoint of the privacy paradox, believing that users are not so naive and that people with privacy concerns will conduct privacy management. Consequently, this study is based on the view of privacy calculation perspective to investigate the privacy behavior of users on social networking sites. Among them, social benefits and privacy concerns are taken as the expected benefits and costs in the viewpoint of privacy calculation. At the same time, this study also explores the antecedents, including positive feedback, self-presentation, privacy policy, and information sensitivity, and the consequence of privacy behavior of weighing benefits and costs, including self-disclosure and three privacy management strategies by interpersonal boundaries (Preventive, Censorship, and Corrective). The survey respondents' characteristics and prior use experience of social networking sites were analyzed. As a consequence, a survey of 596 social network users was conducted online to validate the research framework. The results show that social benefit has the greatest influence on privacy behavior. The most important external factors affecting privacy behavior are positive feedback, followed by the privacy policy and information sensitivity. In addition, the important findings of this study are that social benefits will positively affect privacy management. It shows that users can get satisfaction from interacting with others through social networking sites. They will not only disclose themselves but also manage their privacy on social networking sites after considering social benefits and privacy management on social networking sites, and it expands the adoption of the Privacy Calculus Perspective framework from prior research. Therefore, it is suggested that as the functions of social networking sites increase and the development of social networking sites, users' needs should be understood and updated in order to ensure the sustainable operation of social networking.

Keywords: privacy calculus perspective, self-disclosure, privacy management, social benefit, privacy concern

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5726 3D Geological Modeling and Engineering Geological Characterization of Shallow Subsurface Soil and Rock of Addis Ababa, Ethiopia

Authors: Biruk Wolde, Atalay Ayele, Yonatan Garkabo, Trufat Hailmariam, Zemenu Germewu

Abstract:

A comprehensive three-dimensional (3D) geological modeling and engineering geological characterization of shallow subsurface soils and rocks are essential for a wide range of geotechnical and seismological engineering applications, particularly in urban environments. The spatial distribution and geological variation of the shallow subsurface of Addis Ababa city have not been studied so far in terms of geological and geotechnical modeling. This study aims at the construction of a 3D geological model, as well as provides awareness into the engineering geological characteristics of shallow subsurface soil and rock of Addis Ababa city. The 3D geological model was constructed by using more than 1500 geotechnical boreholes, well-drilling data, and geological maps. A well-known geostatistical kriging 3D interpolation algorithm was applied to visualize the spatial distribution and geological variation of the shallow subsurface. Due to the complex nature of geological formations, vertical and lateral variation of the geological profiles horizons-solid command has been selected via the Groundwater Modelling System (GMS) graphical user interface software. For the engineering geological characterization of typical soils and rocks, both index and engineering laboratory tests have been used. The geotechnical properties of soil and rocks vary from place to place due to the uneven nature of subsurface formations observed in the study areas. The constructed model ascertains the thickness, extent, and 3D distribution of the important geological units of the city. This study is the first comprehensive research work on 3D geological modeling and subsurface characterization of soils and rocks in Addis Ababa city, and the outcomes will be important for further future research on subsurface conditions in the city. Furthermore, these findings provide a reference for developing a geo-database for the city.

Keywords: 3d geological modeling, addis ababa, engineering geology, geostatistics, horizons-solid

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5725 Investigation of Dry-Blanching and Freezing Methods of Fruits

Authors: Epameinondas Xanthakis, Erik Kaunisto, Alain Le-Bail, Lilia Ahrné

Abstract:

Fruits and vegetables are characterized as perishable food matrices due to their short shelf life as several deterioration mechanisms are being involved. Prior to the common preservation methods like freezing or canning, fruits and vegetables are being blanched in order to inactivate deteriorative enzymes. Both conventional blanching pretreatments and conventional freezing methods hide drawbacks behind their beneficial impacts on the preservation of those matrices. Conventional blanching methods may require longer processing times, leaching of minerals and nutrients due to the contact with the warm water which in turn leads to effluent production with large BOD. An important issue of freezing technologies is the size of the formed ice crystals which is also critical for the final quality of the frozen food as it can cause irreversible damage to the cellular structure and subsequently to degrade the texture and the colour of the product. Herein, the developed microwave blanching methodology and the results regarding quality aspects and enzyme inactivation will be presented. Moreover, heat transfer phenomena, mass balance, temperature distribution, and enzyme inactivation (such as Pectin Methyl Esterase and Ascorbic Acid Oxidase) of our microwave blanching approach will be evaluated based on measurements and computer modelling. The present work is part of the COLDμWAVE project which aims to the development of an innovative environmentally sustainable process for blanching and freezing of fruits and vegetables with improved textural and nutritional quality. In this context, COLDµWAVE will develop tailored equipment for MW blanching of vegetables that has very high energy efficiency and no water consumption. Furthermore, the next steps of this project regarding the development of innovative pathways in MW assisted freezing to improve the quality of frozen vegetables, by exploring in depth previous results acquired by the authors, will be presented. The application of MW assisted freezing process on fruits and vegetables it is expected to lead to improved quality characteristics compared to the conventional freezing. Acknowledgments: COLDμWAVE has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grand agreement No 660067.

Keywords: blanching, freezing, fruits, microwave blanching, microwave

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5724 Unfolding Global Biodiversity Patterns of Marine Planktonic Diatom Communities across the World's Oceans

Authors: Shruti Malviya, Chris Bowler

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Analysis of microbial eukaryotic diversity is fundamental to understanding ecosystems’ structure, biology, and ecology. Diatoms (Stramenopiles, Bacillariophyceae) are one of the most diverse and ecologically prominent groups of phytoplankton. This study was performed to enhance the understanding of global biodiversity patterns and structure of planktonic diatom communities across the world's oceans. We used the metabarcoding data set generated from the biological samples and associated environmental data collected during the Tara Oceans (2009-2013) global circumnavigation covering all major oceanic provinces. A total of ~18 million diatom V9-18S rDNA tags from 126 sampling stations, constituting 631 size-fractionated plankton communities were generated. Using ~250,000 unique diatom metabarcodes, the global diatom distribution and diversity across size classes, genus and ecological niches was assessed. Notably, our analysis revealed: (i) a new estimate of the total number of planktonic diatom species, (ii) a considerable unknown diversity and exceptionally high diversity in the open ocean, and (iii) complex diversity patterns across oceanic provinces. Also, co-occurrence of several ribotypes in locations separated by great geographic distances (equatorial stations) demonstrated a widespread but not ubiquitous distribution. This work provides a comprehensive perspective on diatom distribution and diversity in the world’s oceans and elaborates interconnections between associated theories and underlying drivers. It shows how meta-barcoding approaches can provide a framework to investigate environmental diversity at a global scale, which is deemed as an essential step in answering various ecological research questions. Consequently, this work also provides a reference point to explore how microbial communities will respond to environmental conditions.

Keywords: diatoms, Tara Oceans, biodiversity, metabarcoding

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