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The use of fillers in fiber-reinforced epoxy matrix composites to enhance the wear performance of the composite is a widely employed method nowadays. In this study, the effect of incorporating graphite filler into a glass fiber-reinforced composite structure on the tribological properties of the composite was investigated. Composite materials produced using the hand lay-up method with three different levels of graphite filler were compared to unfilled composites in terms of wear behavior under different loads (7 N, 10 N, 15 N) and sliding distances (200 m, 400 m). The influence of load, filler content, and sliding distance on the friction coefficient and wear rate was discussed. When the results are examined, the significant effects of graphite filler on wear volume and friction coefficient are clearly observed. In the composite containing 12% graphite, the wear volume has decreased by almost 96%; this ratio has been around 93% for the composite with 4% graphite filler. As the reinforcement of graphite and force increase, the friction coefficient decreases, whereas with the increase in sliding distance, the friction coefficient declines. Microstructural analysis revealed that the filled composites exhibited less abrasion compared to the unfilled composites, and the surface porosity and craters were shallower.

We aim to investigate the association between smoking and systemic inflammation index (SII), the platelet-to-lymphocyte ratio (PLR), and the neutrophil-to-lymphocyte ratio (NLR) which are derivated from whole blood count. A total of 188 individuals who admitted to organ transplant outpatient polyclinics as donor candidates were included in this retrospective cross-sectional study. Donor candidates were divided into two groups; smokers and non-smokers. SII, PLR, and NLR were formulated from their hemogram during the preparation for donation. Serum C-reactive protein, uric acid, and creatinine levels were also compared between the two groups. P [Med-Science 2023; 12(2.000): 347-51]

In this study characterization of a novel Al66Co20Cu13Mg1 alloy produced by the mechanical alloying method was investigated. The effect of milling time on the produced alloy's microstructural evaluations, microhardness, and thermal behaviors was investigated. Scanning electron microscope and X-ray diffractometer results demonstrated that as the milling time was increased, the homogeneity was increased, the particle size was decreased, crystalline cubic Al(Co, Cu) solid solution, α-Co(Cu, Mg) solid solution phase and Al2Cu phase were formed with the mechanical alloying effect after milling of 50 h. When the powder alloy was milled for 100 h, most of the elemental peaks such as Al and Cu disappeared, and Al3.892Cu6.108 phase was formed. The crystallite size of the alloy powders after 100 h of milling was found as 17.42 ± 2 nm. Moreover, as the milling time was increased, both the lattice strain and dislocation density were increased because of fractures, the formation of new intermetallic phases, and excessive deformations. The microhardness of the pressed powder alloys was increased due to the cold welding and intermetallic phases formed in the powder alloy with increasing milling times. The lowest and highest microhardness values are found to be 275 ± 10 and 376 ± 10 HV for the unmilled alloy and the 100 h of milled alloy, respectively. [ABSTRACT FROM AUTHOR]

Purpose: In patients with end-stage renal disease (ESRD), infections, particularly pneumonias, are the most common cause of hospital admissions and death after cardiovascular diseases. It is recommended that dialysis patients receive the pneumococcal vaccine every five years and the influenza vaccine annually. Our study aims to determine the awareness and factors affecting influenza and pneumococcal vaccination rates in hemodialysis patients. Patients and Methods: This cross-sectional study was conducted on patients undergoing regular hemodialysis treatment in 10 different hemodialysis centers across 4 cities. After excluding patients with less than one year of hemodialysis duration and those under 18 years of age, 548 patients were included in the study. Patients were administered a 20-item survey via face-to-face interview and electronic medical records. Results: Out of the 548 patients, only 19 (3.5%) had knowledge about the pneumococcal vaccine, while 238 (43.4%) had knowledge about the influenza vaccine. There were 220 patients (20.1%) who had knowledge about both vaccines. Among the patients, 95 (17.3%) had received the pneumococcal vaccine, with 41.1% of them having received it five years ago or more. A significant proportion (33.7%) of the patients could not recall the timing of their vaccination. While 183 (33.4%) patients had not received the influenza vaccine, only 140 (25.5%) had been vaccinated regularly every year. The reasons for not receiving the influenza and pneumococcal vaccines were stated as "I do not feel the need because I do not get the flu" (25%) and "I do not know about the pneumonia vaccine" (36.7%), respectively. The ROC curve analysis for the influenza questionnaire score showed an AUC of 0.822 (95% CI 0.787– 0.856), with a p-value of < 0.001. The statistically significant cutoff value for predicting influenza vaccination was determined to be 2.5. In the univariate analysis, dialysis duration (HD duration), diabetes mellitus (DM), and vascular access type were found to be statistically significant. In the multivariate logistic regression analysis, dialysis duration and DM were identified as independent factors predicting a higher level of knowledge about the influenza vaccine (p=0.009, 0.003, and p=0.041). The ROC curve analysis for the pneumococcal questionnaire score showed an AUC of 0.920 (95% CI 0.886– 0.955), with a p-value of < 0.001. The statistically significant cutoff value for predicting pneumococcal vaccination was determined to be 3.5. In the univariate analysis, residence, dialysis duration, and education level were found to be statistically significant. In the multivariate logistic regression analysis, dialysis duration and education level were identified as independent factors predicting a higher level of knowledge about the pneumococcal vaccine (p=0.038, 0.040, and p=0.010). Conclusion: It was observed that awareness and vaccination rates regarding influenza and pneumococcal vaccines were lower in our patients than recommended. We believe that educating patients about vaccines and increasing the sensitivity of hemodialysis physicians, nurses and nephrologists on this issue will increase vaccination rates. [ABSTRACT FROM AUTHOR]

Copyright of Archives of the Turkish Society of Cardiology / Türk Kardiyoloji Derneği Arşivi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nigde Omer Halisdemir University Journal of Engineering Sciences / Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi is the property of Nigde Omer Halisdemir Universitesi (NOHU), Muhendislik Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abdullah b. Cübeyr, Evs kabilesine mensup, ensarın önemli isimlerinden birisidir. İslâm’ın Yesrib’de yayılmaya başladığı ilk zamanlarda Müslüman olarak İslâm’ın yayılması için mücadele veren ve bu uğurda büyük riskleri göze almasıyla bilinen bir kimsedir. Her ne kadar İkinci Akabe Biatı öncesinde iman etmiş olsa da öncesinde Hz. Peygamber’le görüşmek nasip olmamıştı. Hz. Peygamber’e erişmeye burada muvaffak olup ashâb arasındaki yerini aldı. İkinci Akabe Biati’nde yollarının kesişmesiyle iman ettiği peygamberinin yanından hiç ayrılmayıp onun mücadelesinde önemli vazifeler üstlendi. Bedir Savaşı’na iştirak ederek savaş sonunda Hz. Peygamber’in damadı Ebü’l-Âs’ı esir aldı ve savaş sonrasında Hz. Peygamber’in ricası üzerine fidye almadan onu serbest bıraktı. Uhud Savaşı’nda da kritik bir mevki olan Ayneyn Tepesi’ne yerleştirilen okçuların komutanlığı görevini üstlendi. Hz. Peygamber onlara ne olursa olsun buradan ayrılmamaları gerektiğini söylediğinde bunu ciddiyetle uyguladı. Savaşın ilk başlarında Müslümanların lehine gelişen hadiseleri iyi takip edip heyecana kapılmadı. Yenilmek üzere olan müşrik ordusunun kaçtığını gören maiyetindeki okçuların bazıları savaşın bittiğini zannederek tepeden inmeye başladıklarında o kendi yerini korudu. Fakat arkadaşlarının bir kısmı aynı istikrarı sağlayamadıklarından savaşın başından beri fırsat kollayan Hâlid b. Velîd tepedeki okçuların indiğini görünce birliği ile buraya hücum edip Abdullah b. Cübeyr başta olmak üzere birçok okçuyu şehit etti. İşte bu makalede cesur, cömert, yardımsever ve ileri görüşlü olmak gibi birçok güzel vasıfları kendinde barındıran Uhud’un meşhur okçusu Abdullah b. Cübeyr’in hayatı ve faaliyetleri ele alınacaktır.

The shift from traditional, single‐component metals and alloys continues, and researchers are currently investigating alternative materials. This evolution has led to the creation of innovative materials, including hybrid metal‐matrix composites. The present study aims to investigate the microstructural, surface morphological, and thermal properties of a novel Al7075/TiO2/Kaoline hybrid metal‐matrix composite prepared using high‐energy ball milling and sintering methods. In this study, phases related to the composite components are formed depending on the milling time, no undesirable phase is formed, but the peak intensities decreas as the milling time increases. Particle size increases from 63 to 215 μm with increasing milling time. Increasing the kaoline reinforcement ratio and sintering temperature increases the microhardness from 62.27 ± 2 to 75.83 ± 2 HV, and reduces the friction coefficient from 0.82 ± 0.01 to 0.62 ± 0.01. The wear rate of the composite without kaoline addition is 2.1 (mm3 m−1) × 10−3, while with 6 wt% kaoline addition, it decreases to 1.5 (mm3 m−1) × 10−3. There are no cracks in the composite other than plastic deformation due to sintering and wear. Peaks indicating endothermic and exothermic reactions during continuous heating occurr in the 635–750 °C temperature range. [ABSTRACT FROM AUTHOR]

Abstract Background We aimed to present the demographic characteristics, clinical presentation, and outcomes of our multicenter cohort of adult KTx recipients with COVID-19. Methods We conducted a multicenter, retrospective study using data of patients hospitalized for COVID-19 collected from 34 centers in Turkey. Demographic characteristics, clinical findings, laboratory parameters (hemogram, CRP, AST, ALT, LDH, and ferritin) at admission and follow-up, and treatment strategies were reviewed. Predictors of poor clinical outcomes were analyzed. The primary outcomes were in-hospital mortality and the need for ICU admission. The secondary outcome was composite in-hospital mortality and/or ICU admission. Results One hundred nine patients (male/female: 63/46, mean age: 48.4 ± 12.4 years) were included in the study. Acute kidney injury (AKI) developed in 46 (42.2%) patients, and 4 (3.7%) of the patients required renal replacement therapy (RRT). A total of 22 (20.2%) patients were admitted in the ICU, and 19 (17.4%) patients required invasive mechanical ventilation. 14 (12.8%) of the patients died. Patients who were admitted in the ICU were significantly older (age over 60 years) (38.1% vs 14.9%, p = 0.016). 23 (21.1%) patients reached to composite outcome and these patients were significantly older (age over 60 years) (39.1% vs. 13.9%; p = 0.004), and had lower serum albumin (3.4 g/dl [2.9–3.8] vs. 3.8 g/dl [3.5–4.1], p = 0.002), higher serum ferritin (679 μg/L [184–2260] vs. 331 μg/L [128–839], p = 0.048), and lower lymphocyte counts (700/μl [460–950] vs. 860 /μl [545–1385], p = 0.018). Multivariable analysis identified presence of ischemic heart disease and initial serum creatinine levels as independent risk factors for mortality, whereas age over 60 years and initial serum creatinine levels were independently associated with ICU admission. On analysis for predicting secondary outcome, age above 60 and initial lymphocyte count were found to be independent variables in multivariable analysis. Conclusion Over the age of 60, ischemic heart disease, lymphopenia, poor graft function were independent risk factors for severe COVID-19 in this patient group. Whereas presence of ischemic heart disease and poor graft function were independently associated with mortality.

Cytomegalovirus (CMV) is a common virus that causes opportunistic infections in many organ systems in immunocompromised patients. CMV infections are also an important problem in renal transplant patients. CMV infection often causes complications in gastrointestinal system (GIS). CMV duodenitis is a very rare involvement in the GIS. CMV infection can lead to complications, such as erosion, ulcer, adhesion, perforation and bleeding in the bulbus and duodenum. Our case was admitted with the signs of upper GIS bleeding 10 months after renal transplantation. Ulcers in the antrum and bulbus were observed in the endoscopic examination, typical incision bodies for CMV and intranuclear CMV immunoreactivity were detected in duodenal biopsies, and complaints regressed with antiviral treatment.

Background: Two unique biomarkers, soluble form of the urokinase-type plasminogen activator receptor (suPAR) and neopterin, play a crucial role in inflammatory processes. This study aimed to reveal whether it is possible to utilize these biomarkers in predicting tumor prognosis in patients with lung cancers.

Islamic cities exhibit distinctive features aimed at preventing violence, promoting human well-being, and safeguarding the rights of individuals. These characteristics encompass deliberate choices in urban planning and governance. Key attributes include a mosque-centric layout, expansive public squares, green spaces, organized urban fabric, and efficient administrative management. The maintenance of public order was entrusted to the head of state in the capital and governors in other regions, with additional officials such as commanders, ʿāʿīs (judges), Muʿtasib (market overseer), ʿāʿib al-S_h_urʿa (chief of police), and ʿasas (security officers) appointed to ensure security and peace. Akhism provide additional assistance at this stage. This research will delve into Islamic cities' physical infrastructure and institutional framework, focusing on violence prevention. Given Islamic urbanism's diverse geographical spread and historical evolution, the study will analyze select early-period cities, considering urban plans and administrative systems to facilitate comparative analysis. [ABSTRACT FROM AUTHOR]

The high mechanical properties, corrosion resistance and low production costs of aluminum alloys make their use in the aerospace and automobile industries attractive. Addition of reinforcement, and heat treatment are important factors in increasing the physical and mechanical properties of these alloys. In this study, squeeze casting method was used to produce aramid reinforced Al7075 matrix materials and their mechanical, physical and microstructural properties were investigated. The physical (hardness) and mechanical (tensile, flexural) properties of Aramid/Al7075 material were compared with base alloy. Then, the effects of the aging process on the hardness, tensile and flexural strengths of 8%Aramid/Al7075 material (the best mechanical properties) and base alloy were investigated. The polished surfaces of the materials and the fracture surfaces after the tensile test were examined using Scanning Electron Microscopy (SEM), while the phase characterization after aging was performed using X-ray diffraction (XRD). The highest hardness values of non-aged materials were obtained in 12% aramid reinforced material. The highest flexural and tensile stress were obtained from 8% aramid reinforced material among non-aged materials, and their strengths were determined as 454 and 278 MPa, respectively. With an increase in aging time, the mechanical and physical properties of the materials exhibited a significant improvement. However, it was observed that these properties started to decrease after a certain aging time. In heat-treated Aramid/Al7075 materials, the lowest and highest hardness values were obtained as 184 and 205 HB, respectively, after aging for 8 and 20 h. The highest tensile strength (523 MPa) of the Al7075 alloy was obtained at the end of 20 h. The highest tensile strength of aramid reinforced material was obtained as 512 MPa at 16 h aging time. [ABSTRACT FROM AUTHOR]

This study investigates the effects of filler content and type on the mechanical (tensile strength and impact resistance) and tribological properties of woven glass fiber‐reinforced composites (WGFC) produced using three different nanofillers (MgO, CuO, and Al2O3) at various loading levels (0.7, 1.4, and 2.8 wt%). Additionally, analyses of the artificial neural network algorithm were reported for the predictions of wear rate, mass loss, and coefficient of friction (COF) by given applied load, sliding distance, filler ratio, and filler type. The composites were fabricated using the hand lay‐up method. The filled composites were characterized using Fourier Transform Infrared (FTIR) spectroscopy, and the worn surfaces of the samples after the wear test were analyzed using Scanning Electron Microscopy (SEM). The wear resistance of the composite samples improved at 0.7 wt% CuO and 1.4 wt% MgO filler contents. At 200 m sliding distance and 1.4 wt% filler ratio, the highest wear ratio was determined as 55 mm3/m × 10−3 in the Al2O3‐filled composite, and the lowest was determined as 31 mm3/m × 10−3 in the MgO‐filled composite. At 1.4% filler ratio and 15 N load, the lowest friction coefficient was determined as 0.45 μ in MgO‐filled composite, and the highest was 0.56 μ in Al2O3‐filled composite. Al2O3 filler increased the mass loss and wear rate of the composite material. In Charpy impact tests, the maximum impact energy of 13.9 J/m2 was obtained with a 2.8 wt% Al2O3 filler content. Tensile tests showed an increase in tensile strength for all filler contents compared to unfilled composites. The highest tensile strength of 242.1 MPa was achieved with 0.7 wt% CuO reinforcement. Highlights: In all applied wear parameters and filler ratios, the Al2O3 filler adversely affected the wear resistance of the composite, while the MgO filler showed the best performance in terms of wear resistance.All types and ratios of fillers increased the tensile strength compared to the unfilled composite.Contrary to its negative effect on wear, the Al2O3‐filled composites exhibited the highest impact resistance.The prediction analysis of the tribological behavior of composite material using ANN reveals that the Levenberg–Marquardt algorithm fits very well. [ABSTRACT FROM AUTHOR]

Aluminum and its alloys have become the most popular materials in applications aiming to provide lightness due to their low density. However, the low mechanical properties compared to other competitors are among the disadvantages of aluminum and its alloys. This is an important motivation factor in researching strength increasing mechanisms in aluminum and its alloys. In this study, the effects of reinforcement ratio and type on the microstructure, mechanical properties, and wear behavior of the AA7075/B4C composite produced by squeeze casting method were investigated. Two types of materials were produced and compared—non-reinforced AA7075 alloy and AA7075 allo matrix composite reinforced by 4, 8, 10, and 12 wt% B4C. Microstructures of two materials were analyzed by optical microscope, scanning electron microscope and energy distribution spectrometer. In addition, the mechanical and tribological properties of these materials were investigated. Microstructure and scanning electron microscope analysis reveals that the increasing B4C reinforcement ratio increased the tendency of agglomeration in the matrix. Although B4C reinforcement tends to agglomerate, B4C reinforcement positively affected the AA7075 alloy's hardness, tensile and bending strengths, elasticity modules, and wear resistance. [ABSTRACT FROM AUTHOR]

Objectively checking the alleviation of inflammation following BS. [ABSTRACT FROM AUTHOR]

Örgütlerin en önemli amacı varlığını sürdürebilmektir. Bu amacı gerçekleştirecek olan ise insan faktörüdür. insan faktörü ancak etkin ve verimli olduğunda nihai amaca ulaşılacaktır. Etkinlik ve verimliliğe ise tatmin edilmiş ve mutlu olmuş işgörenlerle ulaşılabilir. Bu durum örgütler açısından bilgiyi kullanacak olan nitelikli insan kaynağının önemini artırmaktadır. Dolayısıyla örgütsel bağlılığın sağlanması, örgütlerin amaçlarına ulaşmasında kritik bir rol oynamaktadır. Bu çalışmada Konya bankacılık sektöründe çalışanların iş tatmin faktörlerinden eğitim ve kariyer fırsatlarının örgütsel bağlılığına olan etkisi incelenecektir. Çalışma üç kısımdan oluşmaktadır. Birinci kısımda iş tatmini ve örgütsel bağlılık arasındaki ilişki eğitim ve kariyer fırsatları açısından incelenecek, ikinci kısımda çalışmanın metodolojisi anlatılacak ve üçüncü kısımda çalışmaya ilişkin bulgular verilecek ve sonuçlar yorumlanacaktır.

The aim of this study was to evaluate the oxidative stress and metabolic activities of nurses working day and night shifts. Intensive care unit (ICU) (n=70) and ordinary service (OS) nurses (n=70) were enrolled in the study. Just before and the end of the shifts, blood samples were obtained to measure the participants' oxidative stress parameters. Metabolic activities were analyzed using the SenseWear Armband. Oxidative stress parameters were increased at the end of the shifts for all OS and ICU nurses compared to the beginning of the shifts. Compared to the OS nurses, the ICU nurses' TAS, TOS, and OSI levels were not significantly different at the end of the day and night shifts. The metabolic activities of the OS and ICU nurses were found to be similar. As a result, the OS and ICU nurses' oxidative stress parameters and metabolic activities were not different, and all of the nurses experienced similar effects from both the day and night shifts.Se objetivó evaluar estrés oxidativo y actividades metabólicas de enfermeras en turnos diurnos y nocturnos. Participaron enfermeras de Unidad de Terapia Intensiva (UTI, n=70) y del servicio común (SC, n=70). Se obtuvieron muestras sanguíneas al inicio y al final de los turnos para medir parámetros de estrés oxidativo. Las actividades metabólicas también fueron analizadas utilizando brazaletes SenseWear. Los parámetros de estrés oxidativo aumentaron hacia el final de los turnos de todas las enfermeras SC y UTI, comparados con la medida de inicio. Los niveles de TAS, TOS y OSI no eran significativamente diferentes entre enfermeras SC y UTI al cierre de los turnos diurnos y nocturnos. Las actividades metabólicas de enfermeras SC y UTI se mostraron similares. Consecuentemente, los parámetros de estrés oxidativo y las actividades metabólicas de enfermeras SC y UTI no resultaron diferentes, y todas las enfermeras sufren efectos semejantes en sus turnos, tanto diurnos como nocturnos.O objetivo deste estudo foi avaliar o estresse oxidativo e as atividades metabólicas das enfermeiras em turnos diurnos e noturnos. Enfermeiras da Unidade de Tratamento Intensivo (UTI) (n=70) e do serviço comum (SC) (n=70) participaram do estudo. Logo no início e ao final dos turnos, amostras de sangue foram obtidas para medir parâmetros de estresse oxidativo. Atividades metabólicas também foram analisadas com o uso da braçadeira SenseWear. Parâmetros de estresse oxidativo aumentaram no fim dos turnos de todas as enfermeiras SC e UTI quando comparados ao início dos turnos. Comparados às enfermeiras SC, os níveis de TAS, TOS e OSI das enfermeiras de UTI não eram significativamente diferentes no final dos turnos diurnos e noturnos. Além disso, as atividades metabólicas das enfermeiras de SC e UTI se revelaram como sendo similares. Assim, os parâmetros de estresse oxidativo e as atividades metabólicas das enfermeiras SC e UTI não eram diferentes, e todas as enfermeiras sofrem efeitos semelhantes dos turnos, tanto no dia quanto na noite.