5173 research outputs found
Sort by
AN EFFICIENT METHOD FOR SOLVING FRACTIONAL INTEGRAL AND DIFFERENTIAL EQUATIONS OF BRATU TYPE
No full textIn this paper, the fractional integral and differential equations of Bratu type, which arise in many important physical phenomena, are investigated by an effective technique, Chebyshev Finite Difference Method with the help of fractional derivative in the concept of Caputo. The effect of the fractional derivative in the outcomes has great agreement with the nonlocality of the problem. The truncation and round off errors and convergence analyzes of the present method are also given. Numerical solutions of illustrative examples of the fractional integral and differential equations of Bratu type are given to highlight the validity and performance of the method. The results of the comparisons are very satisfied and show that the proposed technique is more effective and accurate than the other methods
Reduced graphene oxide supported meso-pyridyl BODIPY-Cobaloxime complexes for electrocatalytic hydrogen evolution reaction
No full textCreating innovative catalysts utilizing nonprecious metals for the electrocatalytic hydrogen evolution reaction (HER) poses a significant difficulty. We present a cobaloxime (Cox) complex having pyridine (2-Cox) and tetrafluorophenyl-thio-pyridine (4-Cox) functional groups, which contains a 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) moiety. This combination serves as a catalyst for proton reduction and is immobilized onto reduced graphene oxide (rGO) by pi-pi stacking between the cobaloxime complex and rGO. Moreover, the unique complex's structures were determined through the application of ultraviolet-visible spectroscopy (UV-Vis), Fourier Transform Infrared spectroscopy (FT-IR), X-ray diffraction spectroscopy (XRD), and scanning electron microscopy (SEM). The electrocatalytic activity of the two rGO/2-Cox and rGO/4-Cox electrodes towards hydrogen (H-2) were examined under both alkaline and acidic conditions. The cobaloxime-modified rGO electrodes demonstrate superior electrocatalytic performance for the HER under acidic conditions compared to alkaline conditions. The overpotential at a current density of 10 mA cm(-2) for rGO/2-Cox in 0.5 M H2SO4 is -0.342 V, which is notably lower than the overpotential of rGO/4-Cox (-0.496 V). The Tafel slope for the rGO/2-Cox electrode in a 0.5 M H2SO4 solution is 111 mV.dec(-1), but for the rGO/4-Cox electrode it is 156 mVdec(-1). This discrepancy suggests that the rGO/2-Cox electrode demonstrates better performance in the HER compared to the rGO/4-Cox electrode.Research Fund of the Istanbul Technical University [43721]This work was supported by the Research Fund of the Istanbul Technical University (Project Number: 43721) . The authors thank Prof. Dr. Emin Ciftci for their contribution about XRD measurements
The Impact of the COVID-19 Pandemic on Online Grocery Supply Chain Management: A Case Study in Istanbul
No full textThe COVID-19 pandemic has already crippled normal life all over the world. Its negative impact not only changed the human health system tragically but also disrupted the global economic system. One negative result was ended up in the global food supply chain. As the lockdown times have suspended the manufacturing and logistic activities, therefore, the customers have experienced unimaginable chaos in the shopping markets. Moreover, the purchasing habit of the consumers has remarkably changed compared to pre-pandemic. To meet this new demand pattern, many grocery retailers have tried to adapt to the new normal. While before COVID-19 offline grocery purchasing was popular, after the pandemic, online service got tremendous attention in market. In this study, online grocery supply chain management during the COVID-19 in Istanbul is considered. The aim is to find out how online grocery companies will serve more efficiently during the pandemics and which factors have more effect on the customer’s satisfaction. To do so, first, three popular grocery retailers in Istanbul were selected. Then, a related survey was designed to understand the consumer experience as doing online grocery shopping in COVID-19. Unsurprisingly, a result shows that 60% of the respondents did online shopping every 3-4 days in one week, and the delivery time is the most important factor for the customers. Then, the SWOT analyses were performed accordingly, and the related strategies were summarized. Finally, several managerial implications were given to may improve the company’s online services in COVID-19 and post COVID-19 in Turkey. © 2024, Gazi Universitesi. All rights reserved
The Effect of Oral Water and Ice Popsicle Exposure on the Management of Thirst in the Immediate Postoperative Period
No full textPurpose: Thirst is a high-incidence condition that causes patients to experience problems in the early postoperative period in the postanesthesia care unit (PACU). The study was conducted to determine the effect of oral water and ice application in managing early postoperative thirst. Design: Randomized controlled trial. Methods: The study was conducted between January and April 2017 with 150 patients who were transferred from the operating room of a university hospital to the PACU and met the research criteria. The patients were divided into treatment (water group = 50, ice group = 50) and control (n = 50) groups. Patients in the intervention group received oral water/ice application after admission to the PACU after surgery. Patients in the control group received routine treatment and care. Findings: In intragroup comparisons before and after the application, there was a statistically significant decrease in thirst, dry mouth, dry throat, and difficulty in swallowing in the water and ice groups (P .05). Conclusions: Postoperative oral water/ice application was an effective and safe nursing intervention to reduce thirst, dry mouth, dry throat, and difficulty in swallowing. Ice application was more effective. © 2024 The American Society of PeriAnesthesia Nurse
Review of the relationship between children experiencing parental loss and having a parting anxiety during adulthood
No full textLisansüstü Eğitim Enstitüsü, Psikoloji Ana Bilim Dalı"daha sonra doldurulacaktır""daha sonra doldurulacaktır
Effect of limited-term schema therapy intervention program on panic disorder symptoms
No full textLisansüstü Eğitim Enstitüsü, Psikoloji Ana Bilim DalıPanik Bozukluk (PB) toplumda oldukça yaygın olarak görülen, kişilerin sosyal ve iş yaşamlarını bozan, genellikle diğer psikiyatrik bozukluklarla birlikte seyreden bir ruhsal sağlık sorunudur. Şema Terapi (ŞT) tedavisi zor olarak görülen ruhsal bozuklukları tedavi etmek için bütüncül bir terapi modeli olarak geliştirilmiştir. Bu çalışmanın amacı sınırlı süreli Şema Terapi müdahale (SŞTM) programının PB belirtileri üzerine etkisinin araştırılmasıdır. Yarı deneysel araştırmada 18-45 yaş aralığında 13 PB tanısı konmuş katılımcılara 12 seans SŞTM uygulandı. Veri araçları olarak Young S?ema O?lc?eg?i Kısa Formu 3 (YS?O?-KF3 (YSQ)) ve Mental Bozuklukların Tanısal ve İstatistiksel El Kitabı 5 (DSM-5) Panik Bozukluğu Ölçeği (DPBÖ) kullanıldı. Katılımcılara SŞTM öncesinde ön test (ÖT), SŞTM sonrasında son test (ST) ve altı ay sonra izlem testi (İT) uygulandı. Analizlerde ölçümler arasındaki fark için Friedman Testi, Wilcoxon Signed-Rank testi ve DPBÖ ile YSQ alt ölçeklerinin ilişkisini saptamak için Spearman korelasyon testi kullanıldı. SŞTM sonrası hastaların PB şiddeti puanlarında SŞTM öncesine göre azalma oldu (p=0.001). PB tanısı almış hastalarda SŞTM sonrasında Başarısızlık (p=0.033), Karamsarlık (p<0.001), Sosyal İzolasyon-Güvensizlik (p=0.014), Onay Arayıcılık (p=0.037), Kendini Feda (p=0.043) ve Terk Edilme (p=0.015) şema puanlarında azalma oldu. Bu sonuçlar, altı ay sonraki izlem değerlendirmesinde de devam etti. Bu sonuçlar SŞTM'nin, PB hastaları için alternatif bir müdahale seçeneği olabileceğini düşündürmektedirPanic Disorder (PD) is a mental health problem that is very common in society, disrupts people's social and work lives, and often comorbid with other psychiatric disorders. Schema Therapy (ST) was developed as an integrated therapy model to treat mental disorders that are considered difficult to treat. The aim of this study is to investigate the effect of a limited-term Schema Therapy intervention (SŞTM) program on PD symptoms. In the quasi-experimental research, 12 sessions of SŞTM were applied to 13 participants diagnosed with PD between the ages of 18-45. Young Schema Scale Short Form 3 (YŞS-KF3 (YSQ)) and Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) Panic Disorder Scale (DPDS) were used as data instruments. The participants were administered a pre-test (PT) before SŞTM, a post-test (ST) after SŞTM, and a follow-up test (IT) six months later. In the analyses, Friedman Test, Wilcoxon Signed-Rank test were used for the difference between measurements, and Spearman correlation test was used to determine the relationship between DPDS and YSQ subscales. There was a decrease in PD severity scores of the patients after SŞTM compared to before SŞTM (p=0.001). After SŞTM in patients diagnosed with PD, there was a decrease in schema scores in Failure (p=0.033), Pessimism (p<0.001), Social Isolation-Distrust (p=0.014), Approval Seeking (p=0.037), Self-Sacrifice (p=0.043) and Abandonment (p=0.015). These results continued at the six-month follow-up evaluation. These results suggest that SŞTM may be an alternative intervention option for PD patient
The mediational role of cognitive emotion regulation and mindfulness in the relationship between adult separation anxiety and partner-related obsessive compulsive symptoms
No full textAims: This study aims to investigate the mediating role of cognitive emotion regulation and mindfulness in the relationship between adult separation anxiety and partner-focused obsessive-compulsive symptoms. Methods: The study includes a total of 502 adult participants aged over 18, consisting of 293 women and 209 men, who participated on a voluntary basis. The personal information form, partner-related obsessive-compulsive symptoms scale, cognitive emotion regulation questionnaire, adult separation anxiety questionnaire, and mindful attention awareness scale were used in this research. Statistical analyses were conducted using SPSS 27 software. Results: The results indicate that the self-blame and focusing on thought subscales of the cognitive emotion regulation questionnaire have a mediating role between adult separation anxiety and partner-related obsessive-compulsive symptoms. Conclusion: Mindfulness serves as a mediator in the relationship between adult separation anxiety and partner-related obsessive-compulsive symptoms
On Mahler's Um—numbers in fields of formal power series over finite fields
No full textLet K be a finite field, K(x) be the quotient field of the ring of polynomials in x with coefficients in K and K be the field of formal power series over K. In this paper, we treat polynomials whose coefficients belong to a field extension of degree m over K(x). We show that the values of these polynomials at certain U1-numbers in the field K are Um— numbers in K. © 2024 Societatea de Stiinte Matematice din Romania. All rights reserved.Istanbul Üniversites
Semileptonic ? b ? ?cl?l transition in full QCD
No full textWe investigate the semileptonic decay of Omega b -> Omega cl nul in three lepton channels. To this end, we use the QCD sum rule method in three point framework to calculate the form factors defining the matrix elements of these transitions. Having calculated the form factors as building blocks, we calculate the decay widths and branching fractions of the exclusive decays in all lepton channels and compare the results with other theoretical predictions. The obtained results for branching ratios and ratio of branching fractions at different leptonic channels may help experimental groups in their search for these weak decays. Comparison of the obtained results with possible future experimental data can be useful to check the order of consistency between the standard model theory predictions and data on the heavy baryon decays.Iran National Science Foundation [4025036]K. A. is thankful to Iran National Science Foundation for the partial financial support provided under the elites Grant No. 4025036
Decays of fully beauty scalar tetraquarks to Bq B ¯ q and Bq? B ¯ q? mesons
No full textDecays of the fully beauty four-quark structures X4b and T4b to B meson pairs are investigated in the framework of the QCD three-point sum rule method. We model the scalar exotic mesons X4b and T4b as diquark-antidiquark systems composed of the axial-vector and pseudoscalar diquarks, respectively. The masses m=(18540±50) MeV and m=(18858±50) MeV of these compounds calculated in our previous articles fix possible decay channels of these particles. In the present work, we consider their decays to BqB¯q and Bq?B¯q? (q=u, d, s, c) mesons. In the case of X4b, the mass of which is below the 2?b threshold, these channels determine essential part of its full width ?4b. The tetraquark T4b can decay to the pair ?b?b; therefore, partial widths of processes with B(B?) mesons in the final state permit us to refine our estimate for the full width of this particle. The predictions ?4b=(9.6±1.1) MeV and ?4bFull=(144±29) MeV obtained in this article can be used in future experimental investigations of four b-quark mesons. © 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.Iran National Science Foundation, INSF: 4025036K.?A. is thankful to Iran National Science Foundation (INSF) for the financial support provided under the elites Grant No. 4025036