277 research outputs found
Strong coupling constants of charmed and bottom mesons with light vector mesons in QCD sum rules
We estimate the strong coupling constants of charmed and bottom mesons D(s)∗, D(s)1, B(s)∗, and B(s)1 with light vector mesons ρ, ω, K∗, and φ within the framework of light-cone QCD sum rules. We take into account the contributions of two- and three-particle distribution amplitudes of light vector mesons of twist-2, -3, and -4, and determine the values of the couplings between heavy vector (axial vector) mesons and light vector mesons. These couplings can play an essential role in understanding the charmonium absorption cross section in quark-gluon plasma. Moreover, we compare our estimations to the ones predicted by other approaches
Strong vertices of doubly heavy spin- 3/2 -spin- 1/2 baryons with light mesons in light-cone QCD sum rules
© 2021 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.In this paper, we analyze the vertices of doubly heavy spin-3/2-spin-1/2 baryons with light mesons within the method of light-cone QCD sum rules. These vertices are parametrized in terms of one (three) coupling constant(s) for the pseudoscalar (vector) mesons. The said coupling constants are calculated for all possible transitions. The results presented here can serve as useful information in experimental as well as theoretical studies of the properties of doubly heavy baryons
Determination of the strong vertices of doubly heavy baryons with pseudoscalar mesons in QCD
The strong coupling constant of doubly heavy baryons with light pseudoscalar
mesons and are computed within the light cone sum rules. We take
into account two-particle and three-particle distribution amplitudes of the
said pseudoscalar mesons. We compare our result with the one existing in the
literature
Maternal and fetal outcomes of COVID-19, SARS, and MERS: a narrative review on the current knowledge
OBJECTIVE: Coronavirus infections, including SARS. MERS and COVID-19 have significant impact on global health as well as on pregnancies. The aim of this review was to enlighten and summarize the cumulative knowledge regarding the relationship between Coronavirus outbreaks and pregnancy.
MATERIALS AND METHODS: Literature search was commenced in order to analyze the maternofetal effects of Coronavirus outbreaks.
RESULTS: Fever and cough are the most common presenting symptoms of COVID-19 which mostly affects pregnant women in their 3rd trimester with a maternal mortality rate of 0-77% and fetal and neonatal mortality rates of 1.2%. Fetal demise is common in critically ill pregnant. Pregnancy seems as a worsening factor for SARS and MERS epidemics and both infections affect prominently 3rd trimester pregnancies, although abortion (57%) is a significant risk for cases of early pregnancy. Clinical course of COVID-19, SARS and MERS may be rapid and worse in pregnant women than non-pregnant individuals. Cesarean section is the choice of delivery in most reported women due to mostly obstetrical reasons, although vaginal delivery seems not a worsening factor for the disease.CONCLUSIONS: COVID-19, SARS and MERS have significant detrimental effect on pregnancy. Rapid intervention, treatment, and intensive care support are essential for infected pregnant. Timely delivery is important in order to avoid intrauterine fetal death
Current clinician perspective on non-vitamin K antagonist oral anticoagulant use in challenging clinical cases.
OBJECTIVE: The evolution of non-vitamin K antagonist anticoagulants (NOACs) has changed the horizon of stroke prevention in atrial fibrillation (SPAF). All 4 NOACs have been tested against dose-adjusted warfarin in well-designed, pivotal, phase III, randomized, controlled trials (RCTs) and were approved by regulatory authorities for an SPAF indication. However, as traditional RCTs, these trials have important weaknesses, largely related to their complex structure and patient participation, which was limited by strict inclusion and extensive exclusion criteria. In the real world, however, clinicians are often faced with complex, multimorbid patients who are underrepresented in these RCTs. This article is based on a meeting report authored by 12 scientists studying atrial fibrillation (AF) in diverse ways who discussed the management of challenging AF cases that are underrepresented in pivotal NOAC trials. METHODS: An advisory board panel was convened to confer on management strategies for challenging AF cases. The article is derived from a summary of case presentations and the collaborative discussions at the meeting. CONCLUSION: This expert consensus of cardiologists aimed to define management strategies for challenging cases with patients who underrepresented in pivotal trials using case examples from their routine practice. Although strong evidence is lacking, exploratory subgroup analysis of phase III pivotal trials partially informs the management of these patients. Clinical trials with higher external validity are needed to clarify areas of uncertainty. The lack of clear evidence about complex AF cases has pushed clinicians to manage patients based on clinical experience, including rare situations of off-label prescriptions
A search on the Nikiforov-Uvarov formalism
An alternative treatment is proposed for the calculations carried out within
the frame of Nikiforov-Uvarov method, which removes a drawback in the original
theory and by pass some difficulties in solving the Schrodinger equation. The
present procedure is illustrated with the example of orthogonal polynomials.
The relativistic extension of the formalism is discussed.Comment: 10 page
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Institutional suicide as anomie: decedents speak out for work-related suicides through a Durkheimian exploration of suicide notes in a context without institutional responsibilization for suicide prevention
Data availability statement:
Publicly available information has been analyzed in this study. Links to the online sources have not been included with the article in order to protect the privacy of the individuals affected. Queries regarding the source material should be directed to the corresponding author.Introduction: Drawing on Durkheim’s historical theorization of suicide, we extend his concept of anomic suicide, which is suicide due to a lack of social regulation, to introduce the concept of institutional suicide. We define institutional suicide as suicide due to the absence or decline of institutional policies, practices, and discourses for prevention. In this study, we explore the mechanisms for institutional suicides based on suicide notes Turkey, in a context without institutional responsibilization for prevention. Turkey provides a significant context for studying institutional suicides as policies, practices, and discourses for suicide prevention have been declining for some decades.
Methods: Drawing on publically available suicide notes and narratives in Turkish media outlets, we analyze 17 suicide notes and responses from their institutions of work and friends, family, and colleagues.
Findings and Discussion: We identify two mechanisms that lead to institutional suicides: (1) dehumanization due to lack of recognition and (2) misrecognition through a devaluation of potential. We extend the theory of anomie to institutional settings and offer social policy suggestions to improve institutional responses based on co-design based on suicide notes to prevent institutional suicides and call for institutional responsibilization for preventing work-related suicides.The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article
Exponential Type Complex and non-Hermitian Potentials in PT-Symmetric Quantum Mechanics
Using the NU method [A.F.Nikiforov, V.B.Uvarov, Special Functions of
Mathematical Physics, Birkhauser,Basel,1988], we investigated the real
eigenvalues of the complex and/or - symmetric, non-Hermitian and the
exponential type systems, such as Poschl-Teller and Morse potentials.Comment: 14 pages, Late
Turner syndrome and associated problems in turkish children: A multicenter study
Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosi) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan. © Journal of Clinical Research in Pediatric Endocrinology
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