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Electrochemical Properties of Coumarin 500 Encapsulated in a Liquid Crystal Guided Electrospun Fiber Core and Their Supercapacitor Application
No full textHere, we first report a study on coumarin 500 and liquid crystal including polyacrylonitrile nanofibers in terms of synthesis, characterizations, and supercapacitor performances. SEM, POM, FTIR, and DSC measurements showed that liquid crystal was inserted into the fine polyacrylonitrile nanofibers successfully. Because a strong molecular interaction took place between coumarin 500 and liquid crystal and coumarin 500 was sensitive to the polarity of the medium, the liquid crystal behaved as a guide material for coumarin 500, and it was expected that coumarin 500 was oriented by the director of the liquid crystal along the core of the fiber. The average polyacrylonitrile nanofiber size was between 0.19 to 0.25 mu m, and liquid-crystal-doped and liquid-crystal +coumarin-500-doped fibers exhibited a similar distribution, which is approximately in the 0.30 to 0.60 mu m interval. This proved that the fibers maintained their structure after modifications. Electrochemical evaluation of the different composite nanofibers showed that there was not a significant current increase upon liquid crystal addition into polyacrylonitrile nanofibers at voltammograms. C-s values were enhanced after the coumarin 500 addition into liquid-crystal-doped nanofiber and obtained as 410.60 F/g with a specific energy value of 57.03 Wh/kg. Additionally, the long-term charge-discharge test of the liquid-crystal+coumarin-500-doped polyacrylonitrile graphite electrode showed a very steady distribution between 100th and the 2500th cycles with a 14.12% Cs deviation. This is attributed to the stable and robust network of the PAN nanofiber and the synergetic effect between liquid crystal and coumarin 500 in the nanofiber net
Physical Performance-Based Outcome Measures in Total Hip Arthroplasty Patients: COSMIN-Based Systematic Review
No full textAims: The purpose of the present review was to conduct a COnsensus‐based Standards for the selection of health Measurement Instruments (COSMIN)-based analysis of the physical performance tests in patients with total hip arthroplasty (THA). Method: Databases were searched on February 2021 in “PubMed, Scopus, and Web of Science” literature databases. The “COSMIN tool” was chosen to determine the quality and potential bias of the enclosed papers. “Narrative synthesis” was conducted due to the heterogenous data of the articles. Results: Twelve publications were enrolled in the review. Seven studies analyzed “intra-rater reliability,” seven study “validity,” six study “measurement error,” one study “inter-rater reliability,” and one study presented “responsiveness analysis.” Conclusion: This review proved the psychometric properties of performances tests in THA, regarding COSMIN guidelines. The analysis result of studies yielded a “good” or “fair” quality design. Most of the studies (7) focused on gait-based test. Further studies should focus on “inter-rater reliability, responsiveness, and floor-ceiling effect”
Cost optimization of a microgrid considering vehicle-to-grid technology and demand response
No full textDemand response (DR) programs can offer various benefits especially in microgrid environments with renewable energy systems (RESs) and energy storage technologies when effectively planned and managed. Accordingly, this study proposes an energy management approach for a neighborhood including residential end-users with photovoltaic (PV) systems, a shared energy storage system (ESS) and an electric vehicle (EV) fleet. The proposed approach presents a novel energy credit mechanism (ECM) for the EV fleet and households separately to exploit the EV batteries and store the excess PV energy in the neighborhood through the shared ESS for later use. End-users gain energy credits before a DR event and use these credits during the peak periods to minimize their total energy cost (TEC), resulted in a decrease in the peak demand. Also, the energy credits gained by the EV fleet are used through the vehicle-to-home (V2H) and vehicle-to-grid (V2G) services with the same objective. In order to conduct a more realistic analysis, a battery degradation cost estimation model is employed and the uncertain behavior of the EV users is considered. The case studies show that the proposed optimization strategy has the capability of considerably reducing the energy costs and peak demand
Synthesis, Crystal Structure, Hirshfeld Surface Analysis and Interaction Energy and Energy Framework Studies of Novel Hydrazone Derivative Containing Barbituric Acid Moiety
No full textNew hydrazone derivate, (1Z,2E)-2-(2-(1-(1,3-dimethyl-2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)ethyl) hydrazineylidene)-2-(p-tolyl)acetaldehyde oxime (H2L) was synthesized by 5-acetyl-1,3-dimethyl-barbituric acid and p-methyl isonitrosophenylhydrazine. Its molecular and crystal structures were determined by single crystal X-ray analysis. It belongs to triclinic system P-1 space group with alpha = 7.1722 (3) angstrom, b= 10.5362 (4) angstrom, c =11.7675 (5) angstrom, alpha = 98.844 (4)degrees, beta = 98.882 (4)degrees, gamma =104.330 (4)degrees, Z=2 and V=833.95 (6) angstrom(3). In the molecular structure, the intramolecular N-H center dot center dot center dot O and N-H center dot center dot center dot N hydrogen bonds enclose S(6) ring motifs. In the crystal structure, the intermolecular C-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonds link the molecules into centrosymmetric dimers, enclosing R-2(2)(10) and R-4(4)(10) ring motifs, in which they may be effective in stabilization of the structure. The Hirshfeld surface analysis of crystal structure indicates that the most important contributions for crystal packing are from H center dot center dot center dot H (48.5%), H center dot center dot center dot O/center dot center dot center dot center dot H (23.7%) and H center dot center dot center dot C/C center dot center dot center dot H (9.7%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in crystal packing. Computational chemistry indicates that in the crystal, O-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bond energies are 95.9 and 87.5 kJ mol(-1). The evaluation of the electrostatic, dispersion and total energy frameworks indicates that stabilization is dominated via the nearly equal strengths of the electrostatic and dispersion energy contributions
Anxiety in High School Adolescents by Gender: Friend Attachment, Ineffective Coping with Stress, and Gender in Predicting Anxiety
No full textBackground/purpose - Anxiety is one of the most common mental health problems seen in children and adolescents. Based on this general framework, the first aim of the study is to reveal the prevalence of trait anxiety among adolescents and to determine whether this prevalence differs according to their gender. The second aim is to reveal whether adolescents' ineffective coping styles with stress, friend loyalty, and gender predict trait anxiety. Materials/methods - Data were collected from a total of 531 adolescents (318 females; 213 males). State-Trait Anxiety Inventory, Coping Strategies Scale in Stress Experiences, and the Friend Attachment Scale were used as data collection tools. Results - According to the findings, 18.3% of adolescents had a low level of anxiety, 65.2% were moderate, and 16.0% had a high level of anxiety. In terms of gender, 17.6% of females had a low level of anxiety, 62.3% were moderate, and 20.1% had a high level of anxiety. For the males, 18.3% had a low level of anxiety, 69.5% were moderate, and 11.3% had a high level of anxiety. This gender-based difference was shown to be significant. Another finding showed the adolescents' trait anxiety scores to be negatively correlated with friend attachment, and positive significant relationships revealed between ineffective coping styles. These variables and gender together explain 31.0% of the trait anxiety variance. Conclusion - The findings showed the trait anxiety of female adolescents to be higher than male adolescents. In addition, attention should be paid as to whether attachment to friends and ineffective coping methods with stress are used in research and treatment processes related to trait anxiety
New findings on compositionally distinct maar volcanoes: A case study from Acıgöl (Nevşehir) caldera (Central Anatolia, Turkey)
No full textRecent experiments have largely reshaped our knowledge of maar volcanism. A new evolutionary model promoting the role of explosion depth and vent migration during the formation of maars has provided an alternative approach to previous models. Despite a few attempts to test this model with real cases, there is still a need for field-based studies exploring the depositional characteristics of maars to better understand the factors affecting the model constraints. More investigations on less known felsic maars are required to elucidate the possible differences from their more common mafic counterparts. Here, we explore compositionally distinct monogenetic clusters within the Acıgöl caldera (NW of Central Anatolian Volcanic Province, CAVP), with four felsic maars (İnallı, Kalecitepe, Acıgöl, and Korudağ) and one mafic maar (İcik). Our field observations reveal a successive formation between rhyolitic maars and adjacent lava domes. The mugearitic İcik coalescent maar and the adjacent scoria cone are synchronously formed, which is disclosed by the intercalation of the maar and scoria cone deposits. The geochemistry of the maar juveniles suggests a parental basaltic magma source that has been possibly differentiated by varying degrees of fractional crystallization. Our findings identify the main factors in maar formation (i.e., optimum scaled depth-OSD, water-magma interaction, and basement lithology). We also determine some differences between the felsic and mafic maars in the region, such as higher juvenile content, less amount of sedimentary structure, and a clear transition from phreatomagmatic to magmatic explosions through the end of stratigraphy. All these reflect the complexity of maars, mainly formed by different depths of explosions that occurred in the shallowest few hundred meters rather than a systematic incremental decrease of the eruption locus. Further geophysical and geochronological studies will complete our proposed evolutionary model for the youngest monogenetic activity in the Acıgöl caldera that would also warrant volcanic hazard assessment due to the presence of low-velocity anomalies, shallow Curie depths, and prevalent geothermal activity
Housing in Turkey: Policy, Planning, Practice
No full textThis book presents the major features of the path that the Turkish housing system has followed since 2000. Its primary focus is to build an understanding of housing in Turkey from the policy, planning, and implementation perspectives in the 21st century, interwoven with the effects of neoliberalism. It investigates the social, spatial, and economic outcomes of the shift in philosophy and behaviour by the government regarding housing. The book discusses failures in housing outcomes as government failures, incorrect or inefficient regulations, lack of regulations, and lack of monitoring of the policy outcomes. Chapters on the housing-economy relationship, financialization and indebtedness, housing market experiences based on case studies, and the housing policy provide the reader with an opportunity to observe different outcomes in a world where housing challenges and issues are similar. This book will be of interest to urban planners, political scientists, and sociologists, as well as undergraduate/graduate students and housing sector experts all over the world who are interested in the various dimensions of the housing problem
Coarse Graining on Financial Correlation Networks
No full textCommunity structure detection is an important and valuable task in financial network studies as it forms the basis of many statistical applications such as prediction, risk analysis, and recommendation. Financial networks have a natural multi-grained structure that leads to different community structures at different levels. However, few studies pay attention to these multi-part features of financial networks. In this study, we present a geometric coarse graining method based on Voronoi regions of a financial network. Rather than studying the dense structure of the network, we perform our analysis on the triangular maximally filtering of a financial network. Such filtered topology emerges as an efficient approach because it keeps local clustering coefficients steady and it underlies the network geometry. Moreover, in order to capture changes in coarse grains geometry throughout a financial stress, we study Haantjes curvatures of paths that are the farthest from the center in each of the Voronoi regions. We performed our analysis on a network representation comprising the stock market indices BIST (Borsa Istanbul), FTSE100 (London Stock Exchange), and Nasdaq-100 Index (NASDAQ), across three financial crisis periods. Our results indicate that there are remarkable changes in the geometry of coarse grains
Asthma during pregnancy and lactation
No full textAsthma is one of the most common medical conditions encountered during pregnancy, occurring in 3-8% of pregnant women [1-3]. Pregnancy may also be associated with changes in the course of asthma that were previously present, and asthma may affect pregnancy outcomes
Risikofaktoren für klinische Anfälle bei Neugeborenen mit hypoxisch-ischämischer Enzephalopathie, die mit therapeutischer Hypothermie behandelt wurden
No full textBackground This study aimed to assess the risk factors for clinical seizures in newborns treated with whole body cooling (WBC) for hypoxic ischemic encephalopathy (HIE). Methods Infants with gestational age >= 36 weeks and birth weight >= 2.000 g who were treated with WBC due to HIE were retrospectively enrolled in this study. Patients were assigned to two groups: infants without clinical seizures (Group 1) and infants with clinical seizures (Group 2). The two groups were compared to determine the risk factors for the occurrence of clinical seizures. Results A total of 25 patients (Group 1=10 and Group 2=15) were included in the study. Prothrombin time (PT) was determined as independent risk factor for clinical seizures (p=0.046) and the odds ratio for the effect of PT was found as 1.475 (%95 CI:1.006-2.299). PT (area under the curve [AUC]=0.764; p=0.041), and increased cardiac troponin-I (cTnI) (AUC=0.935; p=0.002) were found to be significant risk factors for predicting the occurrence of clinical seizures. The optimal PT cut-off value was 22.7 sec, with a sensitivity and specificity of 45.4% and 90%, respectively; as well as positive and negative predictive value of 83.3% and 60.0%, respectively. The chest compression in the delivery room, severely abnormal amplitude integrated electroencephalography and high encephalopathy score were also found risk factors for occurrence of clinical seizures. Conclusion Chest compression in the delivery room, high encephalopathy score, prolonged PT, and increased cTnI are significant factors for clinical seizures in newborns treated with WBC for HIE