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Long-term aerosol optical depth analysis and prediction over the Antarctic Peninsula
No full textThe Earth's atmosphere is a system that significantly influences weather patterns and climate by regulating the radiation balance. Disturbances in the balance of incoming and reflected radiation filtered through the atmosphere constitute an interaction driving the planet's temperature, atmospheric circulation, and climate mechanism. The polar regions play a crucial role in maintaining the global climate balance due to their influence on atmospheric circulation patterns. In this context, monitoring atmospheric variables and their changes over time is critical for understanding and predicting global climate change. This study investigated the long-term variations of aerosol optical depth (AOD) in Antarctica, a region highly sensitive to atmospheric changes. The research utilized Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua and Terra AOD products across three different-sized areas. The temporal variations of AOD over a twenty-year period were examined on a spatial basis to understand the patterns and trends of AOD. Furthermore, a comparison was conducted using data from the Marambio Aerosol Robotic Network (AERONET) station and satellite-based data. The evaluations were carried out separately using data from the Terra and Aqua satellites, and similar increasing trends in AOD values were observed for both datasets from 2002 to 2022. The correlation between the four-month mean AOD of Aqua and AERONET, as well as Terra and AERONET, was calculated as 0.6488 and 0.6190, respectively. A Seasonal Autoregressive Integrated Moving Average (SARIMA) model was applied to satellite-based data to predict the dataset's behavior in the near future. The predictive analysis based on these datasets indicated that the most appropriate models were SARIMA(3,1,2)(3,1,0)12 for Aqua and SARIMA(2,1,1)(0,1,3)12 for Terra. The root mean square error values derived from predictions based on these model configurations were 0.030 for the Aqua dataset and 0.018 for the Terra dataset, indicating the accuracy of the models in forecasting the respective data. The predictions demonstrated strong agreement with the observed data, revealing a sustained increase in AOD values over time. © 2025 Elsevier B.V. and NIPRTürkiye Bilimsel ve Teknolojik Araştırma Kurumu, TUBITAK, (119N650)Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TUBITA
KADINLARDA SİGARA VE ALKOL KULLANIMI ÖLÜM KAYGISINI ETKİLER Mİ? KESİTSEL BİR ARAŞTIRMA
No full textBu çalışmada kadınların sigara ve alkol tüketiminin ölüm kaygısı üzerindeki etkisinin incelenmesi amaçlanmıştır. Tanımlayıcı ve kesitsel tipteki araştırmanın örneklemini Mayıs-Ağustos 2024 tarihleri arasında bir Devlet Hastanesinin Kadın Doğum Kliniğine başvuran 590 kadın oluşturdu. Verilerin toplanmasında Kişisel Bilgi Formu ve Türkçe Ölüm Kaygısı Ölçeği kullanıldı. Araştırmaya katılan kadınların yaş ortalaması 30.66±12.7 olarak belirlendi. Araştırmadaki kadınların %20.2’si sigara kullanmakta, %14.1’i alkol kullanmakta ve %9.2’si her ikisini de kullanmaktadır. Sigara kullanan kadınların ölüm kaygısı düzeylerinin, sigara kullanmayan kadınlara kıyasla anlamlı derecede daha yüksek olduğu bulundu. Sigara ve alkol kullanan kadınlarda \"Ölümün Belirsizliği\" ve \"Acı Çekme\" ölçek alt boyutlarının anlamlı düzeyde daha yüksek olduğu belirlendi. Bu çalışma ile sigara ve alkol kullanımının kadınlarda ölüm kaygısını artırdığı sonucuna ulaşıldı. Elde edilen bu bulgular doğrultusunda, hemşirelerin kadın hastalarda sigara ve alkol kullanım durumlarını sistematik olarak değerlendirmeleri ve bu kullanımın ölüm kaygısını artırabileceği konusunda farkındalık oluşturmaları önem arz etmektedir
Effects of fin shapes and orientations with cyclic heating and cooling on melting and solidification of PCM-filled closed space
No full textPhase-change materials (PCMs) offer an effective way to store and release thermal energy to balance the supply and demand for energy. Both the melting and solidification processes have a major impact on how effectively energy storage works and also it is affected by the thermal conditions of the heating or cooling source. Thermal energy storage systems using (PCMs are often limited by slow melting and solidification rates. The current work explores a novel strategy of cyclic heating and cooling for improving the PCM melting and solidification process combined with variations in fin shapes and orientations, to address these inefficiencies. The fins are heated and cooled following cyclic heating and cooling pattern for three different cycle periods (CP) with same amplitude. As a result, PCM is subjected to cyclic heating and cooling. The finite volume method is employed to analyze the impact of cyclic heating-cooling cycles on PCM performance. An analysis is also conducted on the impact of the relative shape of fins-that is, flat, concave, and convex, positions-vertical and horizontal-on the melting and solidification process under three different cycle periods. By applying a finite volume-based computational approach, the numerical model is solved. It is observed that the overall thermal performance of PCM-based energy storage is modulated by the cyclic heating-cooling arrangements. With this, melting time is reduced by 47.1 % compared to horizontal fin arrangement. When the fin pair is arranged vertically (theta = 0 degrees), with the increase in the cycle period to CP3, the amount of stored energy (during the heating cycle) is about 24.7 %. Similarly, the amount of stored energy recovery (during the cooling cycle) is about 43.6 %. When the fin pair is arranged horizontally (theta = 90 degrees), the amount of energy stored is up to 10 % due to the increase in the cycle periods. Similarly, the amount of stored energy recovery (during the cooling cycle) is about 38.5 %. An improved fin designs, combined with cyclic heating-cooling strategies, present an effective solution to enhance PCM-based thermal energy storage systems
Removal of carcinogenic benzidine from water using highly efficient carbon black prepared from sugarcane bagasse
No full textThe use of inexpensive, easily accessible, highly effective, and environmentally friendly adsorbents has been looked into as a perfect substitute for the currently expensive ways of extracting pollutants from wastewater. This study examines the potential use of carbon black (CB) obtained from sugarcane bagasse for the elimination of aromatic amines such as benzidine from simulated wastewater as it is listed as a carcinogenic agent. The contact time, adsorbent dosage, and initial benzidine concentration effects on the system were investigated. According to the findings, the proportion of benzidine removed rose as the adsorbent amount increased. The adsorption of benzidine followed a pseudo-second-order (PSOM) rate equation and fit well Langmuir (LIM) better than the other isotherm models. Maximum adsorption of benzidine on carbon black from sugar cane bagasse (CBB) (99.84%) was observed at pH 2.65 (normal pH), adsorption dose 2 g L-1, and initial concentration of 50 mg L-1 benzidine after contact time 50 min.Science, Technology & Innovation Funding Authority (STDF); Egyptian Knowledge Bank (EKB); Science, Technology & Innovation Funding Authority (STDF) of Egypt [SCSE-31235]Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB). This study was in part supported by The Science, Technology & Innovation Funding Authority (STDF) of Egypt, project number SCSE-31235
New GPS-derived velocity field for Marmara region: Implications for the kinematics along the North Anatolian Fault Zone
No full textThe North Anatolian Fault Zone (NAFZ) is a major strike-slip fault system accommodating the relative motion between the Anatolian and Eurasian plates, extending approximately 1200 km from eastern Turkey to the Aegean Sea in the west. Despite several large earthquakes along the NAFZ during the last century, the northern strand beneath the Sea of Marmara has been seismically silent since the 1766 events, raising concerns about future seismic hazards. The similar to 160-km-long seismic gap, bounded by the 1912 and 1999 ruptures, is considered to have a potential nucleation for a future M > 7 earthquake due to significant strain accumulation over the past two centuries. While previous studies have provided valuable insights into the geometry and deformation patterns of the NAFZ in the Marmara region, discrepancies remain regarding the fault coupling and slip behavior of its submarine segments. The sparse onshore geodetic data, particularly on the northern side of the fault, and limited offshore geodetic observations hinder the ability to entirely resolve fault kinematics and slip characteristics along the northern strand in the Sea of Marmara. To address these limitations, we established a high-spatial-resolution GPS network with both permanent stations and benchmarks, enabling a better understanding of the submarine segment's behavior and seismic potential by investigating the interseismic deformations along the NAFZ segments beneath the Sea of Marmara. Using the recent interseismic GPS velocities, we applied a block model inversion to estimate fault slip rates and coupling ratios along the northern strand of the NAFZ. The checkerboard tests indicate the robustness of our results. This study provides new geodetic constraints that improve our understanding of the seismic potential of the NAFZ beneath the Sea of Marmara, offering critical insights for seismic hazard mitigation in the I(center dot)stanbul metropolitan area.TelluS program of the Institut National des Sciences de l'Univers (INSU); CNRS; Coordinatorship of Scientific Research Projects (BAP) of Hitit University [ODMYO19001.15.002]The authors would like to thank all participants (Emilie Klein, Mehmet Nurullah Alkan, Volkan Ozbey, Turan Erden, Zafer Kose, Kayhan Aladogan, Nurullah S,en, Melih Yamac, Mehmet Atasoy), who helped during the field studies. We also appreciate Tekirdag Metropolitan, Corlu and Marmara Ereglisi municipalities, TUSAGA-Aktif, ISKI-UKBS and Fuat Agalday for their support. We are very grateful to the two anonymous reviewers for their constructive comments and suggestions, which significantly improved the quality of this manuscript. We also thank the Editor for his efforts in handling this manuscript. This study was financially supported by the TelluS program of the Institut National des Sciences de l'Univers (INSU), CNRS and Coordinatorship of Scientific Research Projects (BAP) of Hitit University (project no. ODMYO19001.15.002). The Generic Mapping Tools (GMT) software was used to plot the figures in this manuscript (Wessel et al., 2019)
Pseudospektral Chebyshev yöntemi ile fonksiyonel dereceli çubukların zorlanmış titreşim analizi
No full textOKÜ BAP-2023-PT2-021Eksenel yönde değişken kesit alanına sahip fonksiyonel olarak dereceli çubuğun zorlanmış titreşim analizi ele alınmıştır. Elastik modül ve yoğunluk gibi malzeme özelliklerinin eksenel yönde derecelendirildiği varsayılmıştır. Bu koşullar, geleneksel analitik yöntemlerle çözülmesi zor olan değişken katsayılı kısmi diferansiyel denklemle sonuçlanır. Laplace dönüşümü altında, kısmi diferansiyel denklem eksenel yönde zamandan bağımsız bir sınır değer problemine dönüştürülmüş ve pseudospektral Chebyshev yöntemi ile çözülmüştür. Modifiye edilmiş ters Durbin yöntemi kullanılarak fiziksel uzaydaki yer değiştirmeler elde edilmiştir. Birleştirilmiş sayısal yöntemle elde edilen sonuçlar literatürle doğrulanmıştır. Rastgele seçilen malzeme karışımının yer değiştirme dağılımları üzerindeki etkileri tartışılmıştır
Examination of Nurses' Attitudes Towards Medical Errors
No full textAmaç: Tıbbi hatalar neden oldukları olumsuzluklar sebebiyle sağlık sisteminin içerisinde önemli yer tutmaktadır. Meydana gelen tıbbi hatalar sonucunda hastanede kalış süresi uzamakta, sağlık harcamaları artmakta, sağlık sistemi ve bakıma olan güven azalmakta dolayısıyla sağlık çalışanlarının moral ve motivasyonu da azalmaktadır. Bu nedenle bu araştırma, hemşirelerin tıbbi hatalara yönelik tutumlarını belirlemek amacı ile tanımlayıcı türde planlanmıştır. Metod: Araştırma evrenini, İstanbul’da bir üniversite hastanesinde Mayıs-Ağustos 2018 tarihleri arasında çalışan tüm hemşireler (800), örneklemini ise araştırmaya katılmayı kabul eden 232 hemşire oluşturmuştur. Verilerin toplanmasında “Bilgi Formu’’ ve “Tıbbi Hata Tutum Ölçeği’ kullanılmıştır. Verilerin analizi bilgisayar ortamında Number Cruncher Statistical System 2007 (Kaysville, Utah, USA) programı ile tanımlayıcı istatistiksel metotların yanı sıra Student t Test, Oneway Anova Test ve Bonferroni testi kullanılarak gerçekleştirilmiştir. Bulgular: Hemşirelerin yaş ortalaması 31,54±5,69 (min-mak: 21-50) yıl, çoğunun kadın, evli ve lisans mezunu olduğu belirlenmiştir. Hemşirelerin Tıbbi Hatalarda Tutum Ölçeği toplam puan ortalamaları 3,80±0,33, tıbbi hata algısı alt boyut puan ortalamaları 2,68±0,77, tıbbi hataya yaklaşım puan ortalamaları 3,97±0,50, tıbbi hata nedenleri puan ortalamaları 3,95±0,45 olarak tespit edilmiştir. Yaş, cinsiyet, medeni durum, eğitim durumu, çalışılan klinik, çalışma süresi ve tıbbi hatalara yönelik eğitim alma durumuna göre ölçek toplam ve alt boyut puan ortalamaları açısından istatistiksel olarak anlamlı farklılıklar olduğu saptanmıştır. Sonuç: Sonuç olarak, tıbbi hatalara yönelik kültürün geliştirilmesinde tıbbi hatalara yönelik tutumun önemsenmesi ve bu konuda hemşirelere yönelik eğitim programlarının düzenlenmesi önerilebilir.Aim: Medical errors occupy an important place in the healthcare system due to the negativities they cause. Medical errors cause prolonged hospital stay, increased, healthcare expenses increase, and decreased trust in the healthcare system and care, thus resulting in decreased morale and motivation in healthcare professionals. Therefore, this descriptive study was conducted to identify nurses' attitudes towards medical errors. Method: While the population included all the nurses (n=800) rendering service at a university hospital between May and August 2018, the sample included 232 nurses who were voluntary to participate in the study. Data were collected through an “Information Form” and the “Medical Errors Attitude Scale” and analysed in the computer environment via the NCSS (Number Cruncher Statistical System) 2007 (Kaysville, Utah, USA) software through descriptive statistical methods as well as Student t Test, One-way Anova Test, and Bonferroni test. Findings: The nurses had a mean age of 31.54±5.69 (min-max: 21-50) years, and most of the participants were female, were married and had a bachelor's degree. Their MEAS total mean score was 3.80±0.33. Their mean scores were 2.68±0.77 in the subscale of perception of medical errors, 3.97±0.50 in the subscale of approach to medical errors, and 3.95±0.45 in the subscale of causes of medical errors. Statistically significant differences were determined between the scale total and subscale mean scores in terms of age, gender, marital status, educational background, clinic they worked, tenure, and status of receiving training on medical errors. Conclusion: Consequently, it can be recommended to regard attitudes towards medical errors in improving the culture towards medical errors and organise relative training programmes for nurse
Effects of panax ginseng root powder supplementations into layer quail diets on egg yield, external and internal quality traits, hatchability and blood parameters
No full textThis study uniquely explores the effects of ginseng root powder supplementation in laying quail diets on egg production, egg quality characteristics, hatching performance, and some blood parameters.A total of 144 quails, consisting of 108 females and 36 males, were used. The experiment comprised the control group (YK) and the group with 1% ginseng addition (YG). Each group was divided into threesubgroups, each withsixreplications. At the end of the experiment, it was determined that adding YG did not statistically affect egg production and feed consumption for all weeks and the average of all weeks (P<0.05). The addition of YG was found not to statistically affect the feed conversion ratio except for the seventh week (P<0.05). The effect of adding 1% YG to breeding quail diets on eggshell thickness (mm) did not statistically affect the eggshell thickness for all weeks of the experiment and the average of all weeks (P<0.05). The effect of adding 1% YG to the diets of the experimental groups on shell ratio (%) was found to be statistically insignificant except for the sixth week and the average of all weeks (P<0.05). No differences were detected between the treatment groups regarding hatchability, hatching power, fertility rate, hatching live weight, and first-week live weight in the initial eggs of the quails used in the experiment.Our findings suggest that Panax ginseng root powder added to laying quail diets may improve some performance and egg quality parameters. However, further advanced studies are needed to understand the full potential of ginseng as a feed additive.Coordinator of Scientific Projects (BAP) of Erciyes UniversityThis article is based on research findings that are financially supported by the Coordinator of Scientific Projects (BAP) of Erciyes University, projec
Investigation of the effect of inulin on the physical and sensory properties of tahini
No full textBu çalışmada, susam tahinlerine %1.25–%10 oranlarında inülin eklenmesinin reolojik ve duyusal özelliklere etkisi incelenmiştir. Newtonyen olmayan akış davranışı gösteren tahinler, Herschel-Bulkley modeliyle değerlendirilmiş; eşik kayma gerilimi değerleri -800,9 – 1172 Pa olarak belirlenmiş ve inülin oranı arttıkça azalmış, akışkanlık ise artmıştır. Akma katsayısı (k) değerleri 0,5356 – 800.9 Pa·s n arasında değişmiş ve inülin oranına bağlı olarak akma katsayısı yükselmiştir. R² değerleri 0,9765–0,9871 aralığında bulunmuştur. Duyusal değerlendirmede, en fazla puanı %5 inülinli örnek alırken bunu %10 inülinli örnek takip etmiştir. Bu nedenle %5 inülin içeren tahinin üretimi önerilmektedir.In this study, the effects of 1.25%–10% inulin addition to sesame tahini were investigated on the rheological and sensory properties. Tahinis exhibiting non- Newtonian flow behavior were evaluated using the Herschel-Bulkley model; threshold shear stress values were determined as -800.9–1172 Pa, decreasing with increasing inulin content, while fluidity increased. Flow coefficient (k) values ranged from 0.5356–800.9 Pa·s n , increasing the flow coefficient. R² values were found in the range of 0.9765–0.9871. In the sensory evaluation, panelists appreciated the tahini with 5% inulin the most, followed by the sample with 10% inulin. Therefore, the production of tahini containing 5% inulin is recommended
Powder Metallurgical Processing of Al-5 wt% Cu Matrix Composites Reinforced with MoSi2 and WSi2 Particulates
No full textHerein, investigations on the microstructural, physical, and mechanical properties of molybdenum disilicide (MoSi2)- and tungsten disilicide (WSi2)-reinforced aluminum (Al)-copper (Cu) matrix composites are reported. Powder metallurgy methods such as mechanochemical synthesis (MCS), mechanical alloying (MA), cold pressing, and pressureless sintering are combined to produce composites. First of all, MoSi2 and WSi2 nanoparticles are synthesized by MCS and selective acid leaching, yielding reinforcement materials for Al-Cu matrix. Powder blends consisting of 95 wt% Al and 5 wt% Cu are mixed with metal disilicides at different weight percentages (1, 2, and 5 wt%). MA for 4 h is conducted on these overall blends using a high-energy ball mill. Microstructural and thermal properties of the as-blended and mechanically alloyed powders are determined, and then they are compacted under 450 MPa and sintered at 550 degrees C for 2 h. Mechanical characterization of the composites reveals an increase in hardness and wear resistance with an increasing amount of reinforcement content. Among bulk samples, 5 wt% WSi2-reinforced composites have the highest microhardness (165 +/- 15 HV) and lowest wear rate (1.69 x 10(6) mu m(3) Nm(-1)) values. However, under the compression forces, the highest toughness and strength are obtained from 2 wt%-reinforced composites.Istanbul Technical University Scientific Research Projects (ITU-BAP/YAP Project) [MGA-2023-44054]Infrastructure of this study was provided by Istanbul Technical University Scientific Research Projects (ITU-BAP/YAP Project) with the project number MGA-2023-44054. The authors thank M.Sc. Mertcan Kaba and Professor Dr. Hueseyin Cimeno & gbreve;lu for their help during wear compression tests