Discovery of aza-aromatic anolytes for aqueous redox flow batteries via high-throughput screening

Aza-aromatics have recently emerged as a propitious class of electroactive compounds for energy storage in aqueous redox flow batteries (ARFBs). Here, using high-throughput virtual screening (HTVS), we explored a focused chemical subspace of aza-aromatics to determine the top performing candidates as anolytes in ARFBs. First, we designed a virtual chemical library that contains 13,406 aza-aromatic redox pairs, which was populated through the chemical functionalization of alloxazine, phenazine, and indigo backbones with five different R-groups that are known to affect the key battery properties. Then, we predicted the redox potential, aqueous solubility, and the likelihood of decomposition due to the undesirable hydration and tautomerization reactions of the compounds. An analysis of the decomposition thermodynamics of the aza-aromatic subclasses revealed differing correlations between the redox properties and the chemical stability of the compounds, where the latter is found to strongly depend on the type and quantity of the functional groups. Consequently, a total of 516 anolyte candidates that have lower redox potential and higher solubility than a typical anolyte compound, alloxazine 7-carboxylic acid (ACA), have been identified. Additionally, an automated vendor search for the HTVS-predicted top-performing compounds yielded two molecules that are readily purchasable for experimental validation. Finally, an analysis of the quantitative structure-property relationships showed that the mid-sized aza-aromatics, which are not well-explored in experiments, achieved the largest property tunability windows. Based on the new findings, we also propose a molecular engineering strategy in a way to balance the inherent trade-offs among the redox, solubility and chemical stability features of the aza-aromatic anolytes for ARFBs. &nbsp;</p

Genetics and genetic counseling: Practices and opinions of primary care physicians in Turkey

PURPOSE: The purpose of this study was to assess the educational needs of physicians relating to genetics and genetic counseling in the Denizli region of Turkey. METHODS: Data were collected by questionnaire about physicians' approaches to genetics and genetic counseling. RESULTS: A total of 60 (60.0%) of 100 physicians working in Denizli province returned a questionnaire. Physicians described "their most knowledgeable subjects" in basic genetic information as chromosome abnormalities (41.8%), in genetic disorders as xeroderma pigmentosum (80.0%), and in genetic counseling as directing the parents of and couples with a risk for having a child affected by a genetic disease to an expert or a genetic counseling center (94.8%). Only 20.7% knew the ethical regulations and techniques related to genetic counseling. Physicians thought that they did not have sufficient knowledge about genetics or genetic counseling, and 83.9% would like to attend an educational course. CONCLUSIONS: As a result of this study, a genetics course is planned for physicians so they can actively participate in the prevention and early diagnosis of genetic diseases. ©2007The American College of Medical Genetics

Assessment of femoral neck fractures in the elderly with respect to morphology and mineral density

Background: Femoral neck fractures are among the major orthopaedic problems seen in the elderly and the annual mortality rate is high. The calcium (Ca) and phosphorus (P) ratio can be used as an indicator of osteoporosis. The purpose of this study is to investigate the microarchitectural structure of the fractured regions of femoral head as well as bone mineral density in female and male patients. Materials and methods: The bone tissues taken from the fractured regions of 10 male and 9 female patients were examined with a scanning electron microscope. Electron probe microanalyses were carried out to measure mineral ratios. Results: The bone trabeculae in the fractured area were thin and the cavities between trabeculae were seen to have transformed to irregular and broad structures. There were small valleculae reflecting osteoclastic activity. The analysis showed that the Ca/P ratio at the fracture site averaged 2.20/1 in women and 2.16/1 in men. As age increased, the percentage values of Ca and P decreased and the Ca/P ratio increased. Conclusions: Although there is no significant difference between the parameters of male and female patients, it seems that men can be affected by osteoporosis as much as women

Variational Iteration Method for Volterra Functional Integrodifferential Equations with Vanishing Linear Delays

Application process of variational iteration method is presented in order to solve the Volterra functional integrodifferential equations which have multi terms and vanishing delays where the delay function θ(t) vanishes inside the integral limits such that θ(t)=qt for 0<q<1, t≥0. Either the approximate solutions that are converging to the exact solutions or the exact solutions of three test problems are obtained by using this presented process. The numerical solutions and the absolute errors are shown in figures and tables

Service modularity in e-learning programs: an analysis from the perceived usefulness perspective

Purpose - This study investigates the effects of service modularity on the perceived usefulness (PU) of e-learning programs through the perceived ease of use (PEoU) and service customization. Design/methodology/approach - Structural equation modeling was used to test four hypotheses with survey data from 517 undergraduates in Turkey. Findings - Results show that service modularity affects the PU of e-learning programs through the PEoU. Service customization negatively moderates the effect of service modularity on the PEoU, but positively moderates the effect of the PEoU on the PU of e-learning programs. Practical implications - This study offers insights that support the decisions of policymakers and higher education institutions on how to design appealing e-learning programs cost-effectively. Social implications - This study reveals the determinants of the PU of e-learning, which could support the democratization of access to higher education in emerging countries where barriers to higher education are relatively greater than in developed countries. Originality/value - The concept of service modularity is explored in the e-learning context from the students' perspective. This study shows that the standardized interfaces across course modules increase the PU of e-learning programs by improving the ease of use. It also shows, interestingly, that service customization, enabled by modularity, is not always appreciated by service consumers, because of the potential extra effort demanded in communicating their unique needs to service providers

Modularization of the Front-End Logistics Services in e-Fulfillment

This study exploits service modularity in front-end logistics services in e-fulfillment, from a customer-centric approach, particularly in order management, delivery, and return. Through an online survey of UK customers, the service priorities of 494 respondents via AHP (Analytic Hierarchical Process) were analyzed. Extracting customers' service priorities, ordering behavior, and demographic information as input data, the clustering algorithm KAMILA (KAy-means for MIxed LArge data sets) was further applied. The three identified customer clusters (multichannel shoppers, infrequent shoppers, and online fans) provide preliminary evidence on how commonality and variability aspects of service modularity in front-end logistics services can optimize the number of service options and their performance levels. Therefore, our study, building on value co-creation and modularity, proposes a systematic way of exploiting service modularity for the customer segmentation process that addresses heterogeneous customer preferences cost-efficiently and uncomplicatedly. Furthermore, we provide a framework for the governance of front-end logistics services, guiding outsourcing decisions. Accordingly, it reveals the implications of customer priorities and service decomposition logic choices on value creation. Finally, the propositions formulated aim to develop theoretical foundations for explaining how the heterogeneity in customer priorities for logistics services can be managed with modularity, creating value both for customers and retailers

Dioxin analysis in pine honey from Turkey

The aim of the study is to determine concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and indicator PCBs (ind-PCBs) in pine (honeydew) honey, which is endemic and popular in Turkey. Marchalina hellenica, which lives on Pinus brutia, is the main source of honeydew, and Apis mellifera L. collects the honeydew for making the pine honey. Pine honey is a very important bee product due to the export all over the world. In this study, honey samples were collected from Muğla and were researched via microscope. The quality of honey samples was determined by correlating NHE (Number of Honeydew Elements) to NTP (Number of Total Pollen) ratio and the honey, which has NHE to NTP ratio higher than 4.5 was accepted as a high density-superior quality pine honey. According to identifications, which have been made via microscope, pooled high quality pine honey sample was selected and analysed for dioxin. All the dioxin results were found lower than the European Union regulatory limits

Assessing the performance of analytical methods for propolis – A collaborative trial by the international honey commission

Propolis is a resinous beehive product with extraordinary bioactivity and chemical richness, linked with the botanical sources of the resin. The potential of this product keeps captivating the scientific community, conducting to continuous and growing research on plant sources, composition, or applications in agriculture, cosmetics, pharmacy, odontology, etc. In all cases, the quality assessment is a requirement and relies on methods to extract the bioactive substances from the raw propolis and quantify different components. Unfortunately, besides the absence of international quality requirements, there is also a lack of standardized analytical procedures, despite the presence of several methodologies with unknown reliability, often not comparable. To overcome the current status, the International Honey Commission established an inter-laboratory study, with propolis samples from around the globe, to harmonize analytical methods and evaluate their accuracy. A common set of protocols was matched between twelve laboratories from nine countries, for quantification of ash, wax, and balsamic content in raw propolis, and spectrophotometric evaluation of total phenolics, flavone/flavonol, and flavanone/ dihydroflavonol in the extract. A total of 3428 results (97% valid data), were used to assess the methods’ accuracy following ISO-5725 guidelines. The within-laboratory precision, revealed good agreement levels for the majority of the methods, with relative variance below 5%. As expected, the between-laboratory variance increased, but, with exception of the flavanone method that revealed a clear lack of consistency, all the others maintained acceptable variability levels, below 30%. Because the performance of ultrasounds procedures was low, they cannot be recommended until further improvements are made.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). Thanks to the Programa Apíıcola Nacional 2020-2022 (National Beekeeping Program) for funding the project "Standardization of production procedures and quality parameters of bee products" and to Project PDR2020-1.0.1- FEADER-031734: “DivInA-Diversification and Innovation on Beekeeping Production”. National funding by FCT – Foundation for Science and Technology, through the institutional scientific employment program-contract with Soraia I. Falcão. A special thanks is given to Hartmut Scheiter and Allwex Food Trading GmbH, Bremen, Germany, for providing, handling and delivering the propolis blind samples.info:eu-repo/semantics/publishedVersio