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Thermal acclimation capacity and standard metabolism of the Pacific white shrimp Litopenaeus vannamei (Boone, 1931) at different temperature and salinity combinations
No full textIn aquatic environments, rising temperatures reduce the oxygen content of the water while increasing the oxygen demand of organisms. In intensive shrimp culture, it is of great importance to know the thermal tolerance of cultured species and their oxygen consumption since this affects the physiological condition. In this study, the thermal tolerance of Litopenaeus vannamei was determined by dynamic and static thermal methodologies at different acclimation temperatures (15, 20, 25, and 30 °C) and salinities (10, 20, and 30 ppt). The oxygen consumption rate (OCR) was also measured to determine the standard metabolic rate (SMR) of shrimp. Acclimation temperature significantly affected the thermal tolerance and SMR of Litopenaeus vannamei (P 0.01). Litopenaeus vannamei is a species that has high thermal tolerance and can survive at extreme temperatures (CTmin-CTmax: 7.2-41.9 °C) with its large dynamic (988, 992, and 1004 °C2) and static thermal polygon areas (748, 778 and 777 °C2) developed at the above temperature and salinity combinations and resistance zone (1001, 81 and 82 °C2). The optimal temperature range of Litopenaeus vannamei is the 25-30 °C range, where a decrease in standard metabolism is determined with increasing temperature. Given the SMR and optimal temperature range, the results of this study indicate that Litopenaeus vannamei should be cultured at 25-30 °C for effective production
Optimal insulation of underground spherical tanks for seasonal thermal energy storage applications
No full textThe literature deals specifically with compressed gas characteristics, solar radiation, storage volume and heat load fluctuation in aboveground storage and thermal energy storage (TES) applications. To prevent their negative effects, the use of underground insulated spherical tanks in the storage process has been overlooked. This study details the physical and economic aspects of using insulation in underground spherical tanks for seasonal TES systems. In determining the storage heat load, the degree-time method is recommended for the heat transfer mechanism between soil and storage temperature degrees. Using life cycle cost analysis, the insulation thickness, energy saving and payback period in the underground spherical tank are discussed in detail for hot and cold storage capacities. The results of the study indicated that the degree-hour method can be used in the design of hot and cold TES systems despite the temperature fluctuation. Insulation can be taken care of in hot fluid storage instead of cold alternative. With insulation in the underground spherical tank, it is observed than about 200 % energy savings is possible with approximately 50 % shorter payback period. For the hot fluid storage with insulation, as the storage fluid temperature, soil thermal conductivity and tank diameter rise and the depth falls, but the optimum insulation thickness value increases. As a result, this study is expected to be a guide for further seasonal TES applications using insulation in underground spherical tanks
Kapaciteti posmične sile spojeva namještaja H-tipa izrađenoga od različitih toplinski tretiranih vrsta drva
No full textThe aim of this study was to investigate the effect of wood species, heat treatment, adhesive type and joint technique on shear force capacity of H-type furniture joints. For this purpose, an experimental design that consisted of 3 wood species, 2 treatment processes (untreated, heat-treated), 2 adhesive types (polyurethane (PUR), polyvinyl acetate (PVAc)) and 2 joint techniques (dowel, mortise-tenon (MT)) and 5 replications for each group were prepared, and accordingly, a total of 120 specimens were tested under static shear loads. Siberian pine (Pinus sibirica), Iroko (Chlorophora excelsa), and common ash (Fraxinus excelsior), which are commonly used in furniture constructions, were used as wood species. In general, iroko showed the highest shear force capacity between the wood species. The specimens constructed of heat-treated wood species showed lower shear force capacity by approximately 15 % in comparison to the same untreated specimens. MT joints showed better perfor-mance than dowel joints higher by approximately 21 %. PVAc adhesive gave higher values than PU adhesive by around 5 %. According to the results of four-way interactions, highest shear force capacities of H-type joints were obtained from "Common ash-PVAc-MT" combination in groups of untreated specimens and from "Iroko-PU-MT" combination in groups of heat-treated specimens
Bir Tıp Fakültesi Son Sınıf Öğrencilerinde Anksiyete ve Depresyon Düzeyi ve İlişkili Faktörler
No full textAim: The purpose of this study is to examine, the relationship between of sociodemographic features, positive, negative emotions and risky behaviors of first year students in a medical faculty. Material and methods: A cross sectional analysis has been conducted in which 45 final year students were selected. Of the 45, 45 students participated, yielding a response rate of 100%. Data were collected by Beck Anxiety Scale, Beck Depression Scale and a questionnaire consisting of sociodemographic features. SPSS 22.0 package program was used to analyze the data. The data was examined by using t-test, One way analysis of variance (ANOVA), Mann-Whitney U test and, Ki-kare, p <0.05 was considered as statistically significant. Results: Among the participants 42.2% were women and 60% are studying for the Medical Specialty Exam (MSE). Anxiety was found in 55.6% of the students and depression in 40%. The anxiety scale score averages of those using anxiolytic drugs were found to be significantly higher than those who did not (p = 0.011). The Beck Depression Scale mean scores of those who were prepared for TUS (p = 0.038), those who has more than 2 months for graduation (p = 0.044), those who used anxiolytic medication (p = 0.030) and those who used antidepressant medication (p = 0.046) was significantly higher than the rest of the sample. Conclusion: Students should be monitored continuously and regularly in terms of health outcomes.Amaç:Bu çalışmanın amacı bir tıp fakültesi son sınıf öğrencilerinin anksiyete ve depresyon düzeyi ve ilişkili faktörleri incelemektir. Gereç ve Yöntemler:Kesitsel nitelikteki çalışmanın evrenini 45 son sınıf öğrenci oluşturmaktadır. 45 öğrencinin, 45’i çalışmaya katılmış, ulaşılabilirlik oranı %100’dür. Araştırmanın verileri Beck Anksiyete Ölçeği, Beck Depresyon Ölçeği ve sosyodemografiközelliklerden oluşan bir anket formu ile toplanmıştır. Verilerin analizinde SPSS 22.0 paket programı kullanılmıştır. Verinin değerlendirilmesinde t testi, tek yönlü varyans analizi (ANOVA), Mann-Whitney U testi ve Ki-kare kullanılmış, p0.05 anlamlılık sınırı kabul edilmiştir. Bulgular:Katılımcıların %42.2’si kadın olup, %60’ı Tıpta Uzmanlık Sınavına (TUS) hazırlanmaktadır. Öğrencilerin %55,6 sında anksiyete, %40’nda ise depresyon bulunmuştur. Anksiyolitik özellikte ilaç kullananların anksiyete ölçeği puan ortalamaları, kullanmayanlara göre anlamlı ölçüde yüksek bulunmuştur (p=0.011). TUS’a hazırlananların (p=0.038), mezuniyetine 2 aydan fazla süre kalanların (p=0.044), anksiyolitik özellikte ilaç kullananların(p=0.030) ve antidepresan özellikte ilaç kullananların (p=0.046) Beck Depresyon Ölçeği puan ortalamaları diğer gruplara göre anlamlı ölçüde yüksek bulunmuştur. Sonuç:Öğrenciler sağlık sonuçları açısından sürekli ve düzenli olarak izlenmelidir
Burnout in the maritime industry
No full textToday's intense business relationships put a great deal of stress on employees both physically and mentally. Various occupational groups and organizational structures are faced with important levels of stress due to the difficulties created by working conditions. Because of the physical and environmental working conditions, the maritime industry is regarded as one of the most difficult in the world. In addition to being able to cope with these difficulties, seafarers are expected to be physically and mentally healthy, constantly ready, and able to adapt to the work environment. Consequently, employees suffer from a condition known as "burnout." Some of the causes of burnout are being away from home and loved ones, fatigue, long working hours, limited space, insufficient sleep, and international factors. Therefore, eliminating or minimizing the stress factors that may affect seafarers carries vital importance in terms of ensuring motivation in the organizational work environment. Stress includes the physiological and psychological responses of the individual to excessive and often undesirable stimuli and threatening incidents. Stress manifests itself with a burnout at the organizational level as well as at the individual level. In the maritime sector, it is essential that all maritime enterprises in the world, the education sector, the administrations, and shareholders think about burnout, develop, and implement applications to make the profession sustainable. In this part of the book, the definition and dimensions of burnout will be explained. After defining the concept of burnout, the details of burnout models will be examined, and the results of burnout syndrome will be explained. A conceptual framework will be presented to describe the effect of working conditions in the maritime sector on burnout and the causal relationship between burnout syndrome and accidents and incidents
Haydar Efendi’s Sefaretname in Iran
No full textIn the history of diplomacy, which lasted for centuries from the foundation of the Ottoman Empire to its collapse, the tradition of writing sefaretname (the book of embassy) about the activities of the ambassadors was maintained by many ambassadors. Among the ones written during the Ottoman period, most of the sefāretnāmes that have survived to the present day were written by temporary ambassadors or their entourage. There were also sefāretnāmes scribed by permanent ambassadors. The work named "Haydar Efendi's Sefāretnāme in Iran", which is the subject of the study, was the first sefāretnāme written after the permanent embassy was opened in Iran. This sefāretnāme written by Haydar Efendi who took part in the delegation of Ahmet Vefik Efendi, when appointed as ambassador to Tahran on June 15, 1851, as the embassy undersecretary. In this sefaretname, the journey of the delegation of Ottoman embassy and how the Iranian side welcomed the Ottoman embassy are explained in detail. In addition, the sefaretname contains detailed information about the attitudes and behaviours of both the Ottoman delegation and the ambassador in connection with the welcoming ceremonies by the Iranian side
Determining confidence interval and asymptotic distribution for parameters of multiresponse semiparametric regression model using smoothing spline estimator
No full textThe multiresponse semiparametric regression (MSR) model is a regression model with more than two response variables that are mutually correlated, and its regression function is composed of parametric and nonparametric components. The study objectives are propose a new method for estimating the MSR model using smoothing spline. Also, find the confidence interval (CI) of parameters and the distribution asymptotically of the model parameters estimator. Methods used in this study are reproducing kernel Hilbert space (RKHS) method and a developed penalized weighted least squares (PWLS), and apply pivotal quantity, central limit theorem, and theorems of Cramer-Wold and Slutsky. The results are an 100(1–α)% CI estimate and an asymptotic normal distribution for the parameters of the MSR model. In conclusion, the estimated MSR model is a combined components estimate of parametric and nonparametric which is linear to observation, and CIs of parameters depend on t distribution and estimator of parameters is asymptotically normally distributed. Future time, this study results can be used as theoretical bases to design standard growth charts of the toddlers which can then be used to assess the nutritional status of the toddler
Is ChatGPT Leading Generative AI What is Beyond Expectations?
No full textGenerative AI has the potential to change the way we do things. The chatbot is one of the most popular implementation areas. Even though companies like Google and Meta had chatbots, ChatGPT became popular as it was made publicly available. Although ChatGPT is still in the early stages of its development, it attracted the attention of people and capital groups. It has taken the public interest; people from different fields, ages, and education levels started using ChatGPT. There have been many trials with ChatGPT. It is possible to see a lot of news and shares on the Internet. The study aims to shed light on what is happening in the literature and get an insight into the user expectations of ChatGPT and Generative AI. We also give information about the competitors of ChatGPT, such as Google’s Bard AI, Claude, Meta’s Wit.ai and Tencent’s HunyuanAide. We describe technical and structural fundamentals and try to shed light on who will win the race. We also shared information about the GPT4 version of OpenAI's ChatGPT. We share the early stage due diligence and current situation analysis for all these points. We examine preprint papers and published articles. We also included striking posts on the LinkedIn platform and a compilation of various blogs and news. We also made use of ChatGPT in editing the content of these resources of this study. We can get an insight into the people's interests through their questions submitted to ChatGPT. We can also understand the capabilities of GPT3, GPT4 and also predict further enhancements
Can D-dimer be a diagnostic saviour in patients with acute aortic dissection?
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Critical temperatures and aerobic metabolism in post-larvae of Pacific white shrimp Litopenaeus vannamei (Boone, 1931)
No full textIncreasing water temperature because of climate change decreases the oxygen concentration while increasing the oxygen requirement of species in aquatic environments. Temperature is one of the most important environmental factors affecting the physiological functions of organisms, especially poikilothermic animals, such as shrimp at all levels. In intensive shrimp culture, it is of great importance to know the tolerable temperature range of cultured species and their metabolism since this affects the physiological condition. In this study, critical temperatures (CTM: CTmin and CTmax) of Pacific white shrimp, Litopenaeus vannamei, post-larvae (PL), were determined at different acclimation temperatures of 15, 20, 25, and 30 °C. Lower and upper incipient lethal temperatures (ILT: LILT and UILT) were also calculated for the PL. The thermal windows of the PL were developed using the CTM and ILT values. The standard metabolic rate (SMR) of the PL was determined based on the oxygen consumption rate (OCR) at the different acclimation temperatures mentioned above. The acclimation temperature had a subsequent effect on the thermal tolerance and SMR of the PL (P < 0.01). The PLs of Pacific white shrimp have high thermal tolerance and can survive at extreme temperatures (CTmin and CTmax: 8.2–43.8 °C) with their large dynamic and static thermal window areas of 1128 and 931 °C2, respectively. The optimal temperature range for Pacific white shrimp PLs is the 25–30 °C range, where a decrease in SMR is determined with increasing temperature. The result of this study reveals that a range of 25–30 °C is optimal for effective PL culture of Pacific white shrim