Central Compact Objects: some of them could be spinning up?

Among confirmed central compact objects (CCOs), only three sources have measured period and period derivatives. We have investigated possible evolutionary paths of these three CCOs in the fallback disc model. The model can account for the individual X-ray luminosities and rotational properties of the sources consistently with their estimated supernova ages. For these sources, reasonable model curves can be obtained with dipole field strengths $\sim$ a few $\times 10^9$ G on the surface of the star. The model curves indicate that these CCOs were in the spin-up state in the early phase of evolution. The spin-down starts, while accretion is going on, at a time $t \sim 10^3 - 10^4$ yr depending on the current accretion rate, period and the magnetic dipole moment of the star. This implies that some of the CCOs with relatively long periods, weak dipole fields and high X-ray luminosities could be strong candidates to show spin-up behavior if they indeed evolve with fallback discs.Comment: 5 pages, 3 figures, accepted for publication in MNRA

Bulgar Turistlerin Destinasyon Alışveriş Tercihlerinin Ve Memnuniyet Düzeylerinin Belirlenmesine Yönelik Bir Araştırma: Kırklareli Örneği

Çalışmada, Türkiye’nin Avrupa kıtasında bulunan beş ilinden ve Balkanlara açılan sınır kapılarından biri konumundaki Kırklareli ilini ziyaret eden Bulgar turistlerin destinasyon alışveriş tercihlerinin belirlenmesi ve memnuniyet düzeylerinin ölçülmesi amaçlanmaktadır. Araştırma örneklemi olarak Bulgar turistlerin seçilmesinde destinasyona gelen yabancı turistlerin nerdeyse tamamının bu millete ait olması etkili olmuştur. Bu amaçla ilgili destinasyonu ziyaret eden turistlere kendilerinin cevapladıkları toplam 200 anket formu ulaştırılmıştır. Sosyal bilimler çalışmalarında yaygın bir şekilde kullanılan SPSS veri istatistiki programında yapılan analizler neticesinde (185 anket); turistlerin %80’inin destinasyondan genel olarak memnun ayrıldığı, destinasyona tekrar ziyaret niyetinin bulunduğu ve destinasyonu başkalarına da tavsiye edeceği belirlenmiştir. Turistlerin alışveriş yerlerinin otantikliği/yerelliği, personellerinin tutumu, fiyat açısından uygunlukları, konumları, sorunlara çözüm üretme/şikâyetleri giderme düzeyleri ve personellerin yabancı dil yeterliği konularında düşük memnuniyete sahip oldukları belirlenmiştir. Turistlerin alışveriş yapılan yerin ulaşılabilirliği, alışveriş yerinin ürünlerine ve hizmetlerine garanti vermesi ve alışveriş yerinin ürün ve hizmet açısından güvenilirliği konularında memnuniyetleri ise yüksek düzeyde gerçekleşmiştir.In this study, it is intended to determine the destination shopping preferences and to measure the satisfaction levels of Bulgarian tourists who visited Kırklareli, which is one of the five provinces in the European side of Turkey and one of the border gates to Balkans. The selection of Bulgarian tourists as the research sample was influenced by the fact that almost all foreign tourists coming to the destination belong to this nation. For this purpose, a total of 200 questionnaires were delivered to the tourists visiting the destination. As a result of the analyzes made in the SPSS data statistics program (185 questionnaires), which is widely used in social science studies; it has been determined that 80% of the tourists are generally satisfied with the destination, they intend to visit the destination again and will recommend the destination to others. It has been determined that the tourists had low satisfaction with some of the features of shopping places, which are; authenticity/locality, attitude of staff, price suitability, location, level of solution to problems/resolution to complaints and staff’s foreign language proficiency. On the other hand, the satisfaction of the tourists regarding the accessibility of the shopping place, the guarantee of the products and services of the shopping place and the reliability of the shopping place in terms of products and services were realized at a high level

The Adventure of Geography in Social Studies: A Study on Change

Geography is one of the important building blocks of the social studies course. For this reason, it is necessary to follow the geography discipline, to renew it with up-to-date information, and to ensure its sustainability in the content of the social studies course. This research aims to be understood how geography, one of the important disciplines of social studies, has changed in secondary school social studies textbooks in the historical process. In the research was carried out document analysis, one of the qualitative research methods. Six textbooks prepared according to the social studies curriculum adopted in 2005 and 2018 were examined. Content analysis was utilized in the data analysis process of the research. As a result of the research, it was observed that the geography topics were reduced in terms of quantity in the period between 2005 and 2022, and the current concepts given in the 2018 curriculum were not reflected in the textbooks

Modelling and simulation studies on adaptive controller for alt-azimuth telescopes despite unknown wind disturbance and mass

Numerous ground-based observatories are using small sized ground telescopes for scientific research purposes. The telescopes that are available on the market have three main problems. These issues can be listed as: positioning repeatability, tuning requirement according to different wind speeds for different seasons, and the mass changing via different scientific equipments added to the telescope. This study is aimed at resolving these issues for ground based small alt-azimuth telescopes. Establishing of a set and forget system is performed by designing an adaptive controller. Motor dynamics are taken into consideration for a realistic mathematical model. The Wind-Gust model that consists of a sum of sinusoidal disturbances with unknown phase, amplitude and frequency is used for the wind model. The purposed controller cancels the disturbance effects on the plant while operational positioning and also the makes the plant insensitive to mass changes. The Lyapunov approach is utilised when proving the asymptotic stability. The proposed controller’s success is illustrated with thorough numerical evaluation.The authors would like to thank the technical guidance and funding support of Isik University, Center for Optomechatronics Research and Application (OPAM),and Ataturk University Center for Astrophysical Application and Research (ATASAM). The author(s) received no financial support for the research, authorship, and/or publication of this article.Publisher's Versio

Long-term evolution of dim isolated neutron stars

The X-ray dim isolated neutron stars (XDINs) have periods in the same range as the anomalous X-ray pulsars (AXPs) and the soft gamma-ray repeaters (SGRs). We apply the fallback disc model, which explains the period clustering and other properties of AXP/SGRs, to the six XDINs with measured periods and period derivatives. Present properties of XDINs are obtained in evolutionary scenarios with surface dipole magnetic fields B-0 similar to 10(12) G. The XDINs have gone through an accretion epoch with rapid spin-down earlier, and have emerged in their current state, with the X-ray luminosity provided by neutron star cooling and no longer by accretion. Our results indicate that the known XDINs are not likely to be active radio pulsars, as the low B-0, together with their long periods place these sources clearly below the 'death valley'

Endoscopic Sphenopalatine Artery Ligation in Posterior Epistaxis: Retrospective Analysis of 30 Patients

Objective: Although posterior epistaxis is rarely seen, it is an important medical problem that both decreases the quality of life of the patient and causes difficulties in the management for otorhinolaryngologists. In this study, we aimed to present the results of 30 patients who underwent transnasal endoscopic sphenopalatine artery ligation (TESPAL) for posterior epistaxis in our department.Methods: The records of 30 patients who underwent TESPAL from January 2014 to April 2016 were analyzed retrospectively, and the relationship between perioperative factors and need for revision surgery was assessed.Results: The success rate of TESPAL in posterior epistaxis was 90%. There was no relationship between surgical failure and antiaggregant use (p=0.224), anticoagulant use (p=0.534), hypertension (p=0.564), previous nasal surgery (p=0.279), and bilateral TESPAL application (p=0.279). TESPAL was seen to be effective in cases with Osler–Weber–Rendu disease, pregnancy, and uncontrollable epistaxis after rhinoplasty surgery. Mortality was seen in one of our patients not related to endoscopic ligation in the follow-up period.Conclusion: TESPAL is an effective method in the treatment of posterior epistaxis. Hypertension, antiaggregant or anticoagulant use, bilateral sphenopalatine artery ligation, and previous nasal surgery do not seem to be factors leading to surgical failure

The effect of renin-angiotensin blockers on COVID-19 related mortality: A tertiary center's experience

Background: The first reports on coronaviruse disease 2019 (COVID-19) revealed an exaggerated mortality rate in hypertensive patients. In this regard, concerns about angiotensin-converting enzyme (ACE) inhibitors’ and angiotensin-receptor blockers’ (ARBs) have been aroused. Our aim in this study was to evaluate the potential bad outcome effect of hypertension and anti-hypertensive therapy on COVID-19. Methods: 183 patients with polymerase-chain-reaction (PCR)-proven COVID-19, who were admitted to our hospital and consulted to cardiology department between 15th of March and 15th of April 2020 were included. Data were recruited from hospital records. Results: Thirty-two out of 183 patients with COVID-19 died in hospital. Hypertension incidence was not statistically different between patients who survived and died (76 [50.3%] vs 19 [59.4%, p = 0.352]). Although the usage rate of ACEI were similar among groups, ARB usage rate was significantly higher in patients who died than survived (11 [34.4%] vs 23 [15.2%], p = 0.011). Binary regression analysis showed an association between ARBs and mortality (OR: 0.032, 95% CI 1.045–2.623, p = 0.032). Conclusion: Our study confirmed previous concerns regarding a potential harmful effects of ARBs on COVID-19 related mortality.Kontext: První zprávy o onemocnění koronavirem v roce 2019 (coronavirus disease 2019, COVID-19) ukazovaly na zvýšenou mortalitu jedinců s hypertenzí, což vyvolalo obavy ohledně užívání inhibitorů angiotenzin konvertujícího enzymu (ACEI) a blokátorů receptoru AT1 pro angiotenzin II (ARB). Cílem naší studie bylo posoudit možnost nepříznivého vlivu onemocnění covid-19 na závažnost hypertenze a účinnost antihypertenzní léčby. Metody: Do studie bylo zařazeno 183 pacientů s onemocněním covid-19 prokázaným PCR testem, kteří byli v období od 15. března do 15. dubna 2020 přijati do naší nemocnice a následně odesláni na kardiologickou kliniku. Údaje byly získány z nemocničních záznamů. Výsledky: Celkem 32 ze 183 pacientů s onemocněním covid-19 zemřelo v nemocnici. Incidence hypertenze se mezi pacienty, kteří přežili a zemřeli, statisticky významně nelišila (76 [50,3 %] vs. 19 [59,4 %]; p = 0,352). I když podíly pacientů užívajících inhibitory ACE byly v obou skupinách podobné, léčiva ze skupiny ARB užívalo statisticky významně více pacientů, kteří zemřeli, než těch, kteří přežili (11 [34,4 %] vs. 23 [15,2 %]; p = 0,011). Binární regresní analýza prokázala souvislost mezi užíváním ARB a mortalitou (OR: 0,032; 95% CI 1,045–2,623; p = 0,032). Závěr: Naše studie potvrdila původní obavy týkající se možných škodlivých účinků lékové skupiny ARB na mortalitu v souvislosti v onemocněním covid-19

Discovery of a small molecule that selectively destabilizes Cryptochrome 1 and enhances life span in p53 knockout mice

Cryptochromes are negative transcriptional regulators of the circadian clock in mammals. It is not clear how reducing the level of endogenous CRY1 in mammals will affect circadian rhythm and the relation of such a decrease with apoptosis. Here, we discovered a molecule (M47) that destabilizes Cryptochrome 1 (CRY1) both in vitro and in vivo. The M47 selectively enhanced the degradation rate of CRY1 by increasing its ubiquitination and resulted in increasing the circadian period length of U2OS Bmal1-dLuc cells. In addition, subcellular fractionation studies from mice liver indicated that M47 increased degradation of the CRY1 in the nucleus. Furthermore, M47-mediated CRY1 reduction enhanced oxaliplatin-induced apoptosis in Ras-transformed p53 null fibroblast cells. Systemic repetitive administration of M47 increased the median lifespan of p53−/− mice by ~25%. Collectively our data suggest that M47 is a promising molecule to treat forms of cancer depending on the p53 mutation

Bazı sebze türlerinin organik ve konvansiyonel tohum üretiminde verim ve kalite özelliklerinin karşılaştırılması

Bu çalışma, bazı sebze türleri tohumlarının organik ve konvansiyonel tohum yetiştiriciliği sonrası, verim ve kalite özelliklerinin karşılaştırılması ve piyasadaki organik tohum eksikliğine bir ışık tutmak amacıyla yapılmıştır. Çalışmanın bitkisel materyalini “Riogrande” domates çeşidi, “Pala Yağlık” biber çeşidi, “Yedikule” marul çeşidi ile “Kar çiçeği” karnabahar çeşidi tohumları oluşturmuştur. Denemeler E.Ü. Ziraat Fakültesi Menemen Araştırma Uygulama ve Üretim Çiftliği’nde ve E.Ü. Tohum Teknolojisi Uygulama ve Araştırma Merkezi’nde gerçekleştirilmiştir. Çalışmada kullanılan türler, tohum üretimi sırasında türlere göre bitki gelişim özellikleri (bitki boyu, bitki çapı, v.b.), meyve verim ve kalite özellikleri (meyve boyu, kuru madde miktarı, meyve ağırlıkları v.b.) ve elde edilen tohumlarda tohum kalite özellikleri (1000 dane ağırlığı, optimum çimlenme ve çıkış ve stres koşullarında çıkış özellikleri) testleri gerçekleştirilmiştir. Elde edilen veriler değerlendirildiğinde bitkisel gelişim özellikleri bakımından konvansiyonel ve organik bitkiler arasında bir farklılık belirlenmemesine rağmen konvansiyonel uygulamada meyve ve tohum veriminin daha yüksek olduğu belirlenmiştir. Ancak bu verimdeki yükseklik tohum kalitesine yansımamıştır. Organik ve konvansiyonel koşullarda üretilen tohumlar benzer çimlenme ve çıkış hızı ile gücü değerlerine sahip olmuştur. Sonuç olarak organik sebze tohumu üretiminin iyi bakım koşulları ile gerçekleştirilebileceği ve tohumların kalitesinde de önemli bir kaybın oluşmayacağı ortaya konmuştur