274 research outputs found
Vertex diffracted edge waves on a perfectly conducting plane angular sector
The problem of electromagnetic scattering from a perfectly-conducting plane angular sector has been of interest for many years. An exact solution for this problem has been developed based on the separation of variables in sphero-conal coordinate system. In this solution, fields and currents are expressed in terms of scalar wave functions that are the solutions of a two parameter eigenvalue problem of two coupled spherical Lame differential equations and spherical Bessel functions. The resulting expressions are in the form of eigenfunction expansions. These expansions are slowly convergent and not suitable for high frequency scattering calculations. Despite their computational advantages, high-frequency modeling techniques fail to provide accurate results for many classes of problems. Lack of a vertex diffraction coefficient is a major factor that limits the accuracy of the high frequency diffraction techniques. Furthermore, the vertex-excited surface currents are strongly guided by the edges of the angular sector creating strong singularities on the current and charge densities. The singular behavior of the current density near the sharp edges of a scattering target is also known as the edge condition and should be modeled properly in numerical solutions to improve the accuracy. In this thesis, numerical diffraction coefficients are derived for vertex-diffracted edge waves induced on an infinitely-thin, perfectly conducting semi-infinite plane angular sector. The diffraction coefficients are formulated to be used in a purely high-frequency modeling of a scattering problem. The current density on the surface of the plane angular sector is modeled using the physical theory of diffraction (PTD). The vertex-diffracted currents are defined as the difference between the exact and PTD currents. The difference current is then modeled as a wave traveling away from the corner with unknown amplitude and phase factors. The unknown coefficients for the vertex-diffracted currents are calculated by using a least squares fit approximation. The vertex-diffracted currents are successfully modeled even for very narrow angular sectors for arbitrary directions of incidence. Illustrative examples are presented to demonstrate the substantial improvement provided by the vertex-diffracted currents to the accuracy of RCS patterns. Another aspect of the research in this thesis is the development of higher-order basis functions for the Method of Moments (MoM) solution. A set of divergence-conforming basis functions was developed to model the singular behavior of the surface currents near the edges and corners of an infinitely-thin, perfectly-conducting polygonal flat plate. The basis functions are derived by imposing the edge and corner conditions on the first order basis functions. It is demonstrated that, even though the new basis functions are not highest order complete, they provide accurate results without incurring complexity in the analysis or additional computational requirements
THE RELATION OF RELIGIOUS ATTITUDES AND BEHAVIOURS WITH DEPRESSION IN BOARDING QURAN COURSE STUDENTS
Background: Boarding Quran courses are religious institutions where course attendees spend large part of the year. Depression
is an ever-increasing health problem. So, it is worth to study on the effects of religion concept and religious belief and behaviours’
that religion concept brings, on depression. The main purpose of this study, is to analyse the effect of religious attitudes and
behaviours on depression in Quran course / hafiz students.
Subjects and methods: The study is a cross sectional, case-control survey research. Boarding Quran courses and high schools
were visited in Samsun city. A total of 956 participants enrolled between June 2015 and December 2015 were included into study
from Samsun city of Turkey. Volunteers, 13 years and over ones without any psychiatric disorders were included in the study.
Religious attitude-behaviour inventory and Beck’s depression inventory were used in the study.
Results: Median point of case group attitude scale was 49, control group’s was 57 and difference among both has a statistical
meaning (p<0.001). Beck’s depression score average of case group is 12.93±9.33, its control group’s average is 13.74±11.14 and
difference between them is not important. Median score of both groups are 11. When scores of attitude and depression scales
compared with each other in terms of demographic parameters, there is a difference among group, gender, age and education
parameters (p<0.001).
Conclusions: It was seen that religious attitudes and behaviours can be protective for boarding Quran course students but it
cannot be enough by itself
DolphinNext: a distributed data processing platform for high throughput genomics
BACKGROUND: The emergence of high throughput technologies that produce vast amounts of genomic data, such as next-generation sequencing (NGS) is transforming biological research. The dramatic increase in the volume of data, the variety and continuous change of data processing tools, algorithms and databases make analysis the main bottleneck for scientific discovery. The processing of high throughput datasets typically involves many different computational programs, each of which performs a specific step in a pipeline. Given the wide range of applications and organizational infrastructures, there is a great need for highly parallel, flexible, portable, and reproducible data processing frameworks. Several platforms currently exist for the design and execution of complex pipelines. Unfortunately, current platforms lack the necessary combination of parallelism, portability, flexibility and/or reproducibility that are required by the current research environment. To address these shortcomings, workflow frameworks that provide a platform to develop and share portable pipelines have recently arisen. We complement these new platforms by providing a graphical user interface to create, maintain, and execute complex pipelines. Such a platform will simplify robust and reproducible workflow creation for non-technical users as well as provide a robust platform to maintain pipelines for large organizations.
RESULTS: To simplify development, maintenance, and execution of complex pipelines we created DolphinNext. DolphinNext facilitates building and deployment of complex pipelines using a modular approach implemented in a graphical interface that relies on the powerful Nextflow workflow framework by providing 1. A drag and drop user interface that visualizes pipelines and allows users to create pipelines without familiarity in underlying programming languages. 2. Modules to execute and monitor pipelines in distributed computing environments such as high-performance clusters and/or cloud 3. Reproducible pipelines with version tracking and stand-alone versions that can be run independently. 4. Modular process design with process revisioning support to increase reusability and pipeline development efficiency. 5. Pipeline sharing with GitHub and automated testing 6. Extensive reports with R-markdown and shiny support for interactive data visualization and analysis.
CONCLUSION: DolphinNext is a flexible, intuitive, web-based data processing and analysis platform that enables creating, deploying, sharing, and executing complex Nextflow pipelines with extensive revisioning and interactive reporting to enhance reproducible results
Coal Consumption and Economic Growth in Turkey
This aim of this paper is to use asymmetric causality tests to examine the coal consumption and Gross Domestic Product (GDP) relationship in Turkey based on data from 1980 to 2006. To investigate this relationship, a multivariate system is employed by including fixed capital formation and labor force variables into the model. The empirical results obtained from asymmetric causality tests show no causality for coal consumption and GDP relationship in Turkey. The results indicate that coal consumption does not affect growth; hence, energy conservation policies may be pursued without adversely affecting growth in Turkey. Thus, neutrality hypothesis is confirmed for Turkey. This means that a decrease in coal consumption does not affect economic growth and vice versa. In this case, policymakers should explore the feasibility of either decreasing the coal consumption or increasing the efficiency of coal consumption.
Keywords: Economic growth; coal consumption; asymmetric causality; Turkey
JEL Classifications: O; Q4
Thieno[3,2-b]thiophene and triphenylamine-based hole transport materials for perovskite solar cells
Heterocyclic compounds have played significant roles in achieving high performance as hole transport materials (HTMs) for perovskite solar cell (PSC) applications. Various studies have focused on the development of fused heterocyclic conjugated structures for hole transport materials. In this report, three novel π-extended conjugated materials (M1-M3), based on thieno[3,2-b]thiophene (TT) and 4,4′-dimethoxytriphenylamine [TPA(OMe)2], were designed and successfully synthesized via Palladium (0) catalyzed Suzuki coupling reaction. Their optical, electrochemical, and thermal properties were investigated by UV-Vis, fluorescence, cyclic voltammetry, and thermal analysis. The materials were utilized as hole transport materials in p-i-n architecture perovskite solar cells, which displayed performances of open-circuit voltage (Voc) as high as 1,050 mV, a maximum short-circuit current (Jsc) of 16,9 mA/cm2, a maximum fill factor (FF) of 29.3%, and a power conversion efficiency (PCE) of 5.20%. This work demonstrated that thieno[3,2-b]thiophene and TPA(OMe)2-based structures are promising cores for high-performance hole transport materials in perovskite solar cell architecture
Effects of knee joint angle on global and local strains within human triceps surae muscle: MRI analysis indicating in vivo myofascial force transmission between synergistic muscles
Purpose Mechanical interactions between muscles have been shown for in situ conditions. In vivo data for humans is unavailable. Global and local length changes of calf muscles were studied to test the hypothesis that local strains may occur also within muscle for which global strain equals zero. Methods For determination of globally induced strain in m. gastrocnemius in dissected human cadavers several knee joint angles were imposed, while keeping ankle joint angle constant and measuring its muscle-tendon complex length changes. In vivo local strains in both gastrocnemius and soleus muscles were calculated using MRI techniques in healthy human volunteers comparing images taken at static knee angles of 173° and 150°. Results Imposed global strains on gastrocnemius were much smaller than local strains. High distributions of strains were encountered, e.g. overall lengthened muscle contains locally lengthened, as well as shortened areas within it. Substantial strains were not limited to gastrocnemius, but were found also in synergistic soleus muscle, despite the latter muscle-tendon complex length remaining isometric (constant ankle angle: i.e. global strain = 0), as it does not cross the knee. Based on results of animal experiments this effect is ascribed to myofascial connections between these synergistic muscles. The most likely pathway is the neurovascular tract within the anterior crural compartment (i.e. the collagen reinforcements of blood vessels, lymphatics and nerves). However, direct intermuscular transmission of force may also occur via the perimysium shared between the two muscles. Conclusions Global strains imposed on muscle (joint movement) are not good estimators of in vivo local strains within it: differing in magnitude, as well as direction of length change. Substantial mechanical interaction occurs between calf muscles, which is mediated by myofascial force transmission between these synergistic muscles. This confirms conclusions of previous in situ studies in experimental animals and human patients, for in vivo conditions in healthy human subjects. © 2011 Springer-Verlag
Evaluation of nutritional status in pediatric intensive care unit patients: the results of a multicenter, prospective study in Turkey
IntroductionMalnutrition is defined as a pathological condition arising from deficient or imbalanced intake of nutritional elements. Factors such as increasing metabolic demands during the disease course in the hospitalized patients and inadequate calorie intake increase the risk of malnutrition. The aim of the present study is to evaluate nutritional status of patients admitted to pediatric intensive care units (PICU) in Turkey, examine the effect of nutrition on the treatment process and draw attention to the need for regulating nutritional support of patients while continuing existing therapies.Material and MethodIn this prospective multicenter study, the data was collected over a period of one month from PICUs participating in the PICU Nutrition Study Group in Turkey. Anthropometric data of the patients, calorie intake, 90-day mortality, need for mechanical ventilation, length of hospital stay and length of stay in intensive care unit were recorded and the relationship between these parameters was examined.ResultsOf the 614 patients included in the study, malnutrition was detected in 45.4% of the patients. Enteral feeding was initiated in 40.6% (n = 249) of the patients at day one upon admission to the intensive care unit. In the first 48 h, 86.82% (n = 533) of the patients achieved the target calorie intake, and 81.65% (n = 307) of the 376 patients remaining in the intensive care unit achieved the target calorie intake at the end of one week. The risk of mortality decreased with increasing upper mid-arm circumference and triceps skin fold thickness Z-score (OR = 0.871/0.894; p = 0.027/0.024). The risk of mortality was 2.723 times higher in patients who did not achieve the target calorie intake at first 48 h (p = 0.006) and the risk was 3.829 times higher in patients who did not achieve the target calorie intake at the end of one week (p = 0.001). The risk of mortality decreased with increasing triceps skin fold thickness Z-score (OR = 0.894; p = 0.024).ConclusionTimely and appropriate nutritional support in critically ill patients favorably affects the clinical course. The results of the present study suggest that mortality rate is higher in patients who fail to achieve the target calorie intake at first 48 h and day seven of admission to the intensive care unit. The risk of mortality decreases with increasing triceps skin fold thickness Z-score
Whole-exome resequencing distinguishes cystic kidney diseases from phenocopies in renal ciliopathies
Rare single-gene disorders cause chronic disease. However, half of the 6,000 recessive single gene causes of disease are still unknown. Because recessive disease genes can illuminate, at least in part, disease pathomechanism, their identification offers direct opportunities for improved clinical management and potentially treatment. Rare diseases comprise the majority of chronic kidney disease (CKD) in children but are notoriously difficult to diagnose. Whole exome resequencing facilitates identification of recessive disease genes. However, its utility is impeded by the large number of genetic variants detected. We here overcome this limitation by combining homozygosity mapping with whole exome resequencing in 10 sib pairs with a nephronophthisis-related ciliopathy, which represents the most frequent genetic cause of CKD in the first three decades of life. In 7 of 10 sib-ships with a histologic or ultrasonographic diagnosis of nephronophthisis-related ciliopathy we detect the causative gene. In six sib-ships we identify mutations of known nephronophthisis-related ciliopathy genes, while in two additional sib-ships we found mutations in the known CKD-causing genes SLC4A1 and AGXT as phenocopies of nephronophthisis-related ciliopathy. Thus whole exome resequencing establishes an efficient, non-invasive approach towards early detection and causation-based diagnosis of rare kidney diseases. This approach can be extended to other rare recessive disorders, thereby providing accurate diagnosis and facilitating the study of disease mechanisms
A research on the effects of social responsibility activities on employees' performance in companies
Sosyal sorumluluk kavramı, özünde tüm bireylerin ve kurumların çevreye ve topluma karşı yapması gerekenler olduğunu ifade ederken genelde daha çok işletmelerin sosyal sorumlulukları anlamında kullanılmaktadır. Fakat zamanla işletmelerin sorumluluk alanları genişlemiştir. İşletmelerden beklenen artık çevre sorunları, çalışan hakları, insan hakları vb. konularda asgari standartların ötesinde çalışmalar yapmasıdır. Çalışmanın verileri, Manisa Organize Sanayi Bölgesinde faaliyet gösteren dört firmada yapılmıştır ve 119 çalışandan geri dönüş alınmıştır. Anketin uygulandığı firmalar farklı sektörlerde yer almaktadır. Sektör bazında bakıldığında firmalardan bir tanesi panjur ve alüminyum, iki tanesi otomotiv ve bir tanesi de ağır iş makinesi yedek parça üretimindedir. Çalışmanın hipotezleri frekans, faktör analizleri yoluyla test edilmiştir. Araştırma sonucunda, işletmelerin çalışanlara karsı sosyal sorumluluklarının çalışan performansı üzerinde etkili olduğu bulunmuştur. Çalışanlara karsı sosyal sorumluluğu oluşturan değişkenlerden, işyerinde sağlıklı ve güvenli çalışma koşulları sağlama, disiplini sağlama, ücret, işin yapısı en güçlü etkiye sahip değişkenler olduğu sonucuna ulaşılmıştır. Bu faaliyetler sadece SA 8000'i değil çalışan performansını da olumlu yönde etkilediği gözlemlenmiştir. Anahtar Kelimeler: 1) Sosyal Sorumluluk, 2) Performans Kriterleri, 3) Çalışan Performansı, 4) SA 8000 Sosyal Sorumluluk Standardı The concept of social responsibility is being used as the social responsibility of corporations generally while representing the responsibilities of both all individuals and organizations regarding the environment and the society basically. However, the scope of organizational responsibility have expanded in time. The expectation from the organizations is to exceed the minimum standards on environmental problems, employee rights, human rights and the like. In this study, the organizations' social responsibility attitudes towards their employees and the effect of this situation on employee performance have been measured. The data of the study has been gathered from 119 employees who work in 4 different factories located in Manisa Industrial Zone. The sample firms in this study operate in different sectors. Two of the sampling firms operate in automotive industry, one of them operates in aluminium and window blind and one of them operates in spare parts for heavy industrial engines. As a result of this study, it has been found out that organizations' social responsibility towards their employees do effect the performance of their employees. Of the variables that form the social responsibility towards the employees, maintaining healthy and secure working conditions, setting the discipline, salary, the job structure have the most powerful effect on performance. These activities do not only effect SA 8000 applications in a favorable direction, they also effect employee performance positively. Keywords: 1) Social Responsibility 2)Performance Criteria 3) Employee Performance 4) SA 8000 Social Responsibility Standar
Diagnostics and modeling of yttria-stabilized zirconia formation in solution-precursor plasma-spray process
Thermal barrier coatings produced by solution-precursor plasma-spray (SPPS) process have been shown to offer superior thermal properties and durability. The microstructure of these coatings combines favorable properties of conventional air plasma spray (APS) and electron beam physical vapor deposition (EB-PVD) coatings by providing evenly spaced, through-thickness vertical cracks and uniformly distributed porosity resulting in good strain tolerance and low thermal conductivity. This experimental and computational study aims at clarifying some of the key aspects of this process through diagnostics of the actual process, modeling of vaporization and precipitation within droplets and through model experiments which utilize a combustion flame instead of a plasma jet. The work also includes characterization of the combustion flame and study of the possibility of coating formation utilizing combustion processes instead of plasmas. Plasma-extracted sample indicate presence of spherical sintered polycrystalline particles of 100 nm to 1 micron. Characterization of the precursor spray show that the mean droplet size is about 40 micron suggesting droplet disintegration in the process. Modeling of the heat and mass transfer around the droplets and solute precipitation predict formation of shell type structures and ceno-spheres supported by the experimental evidence of shell type structures in the single pass plasma experiments. Combustion flame experiments were found to produce sintered polycrystalline tetragonal yttria-stabilized zirconia particles similar to the plasma-extracted samples. The microstructural and compositional evolution of the ceramic particles was characterized as a function of downstream distance in the flame jet.
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