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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 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.)

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]

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]

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.

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]

We aim to investigate the association between smoking and systemic inflammation index (SII), the platelet-to-lymphocyte ratio (PLR), and the neutrophil-tolymphocyte 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<0.05 was assumed as statistically significant. Seventy-five of 188 individuals (39.9%) were smokers. Smokers were older compared to nonsmokers and the mean smoking longevity was 21.14±12.92 years. SII, NLR, PLR, and CRP levels were higher in the smokers (p=0.020, p=<0.001, p=<0.001, and p=0.038, respectively). Smoking longevity had an impact on SII, PLR, NLR, and CRP (all p<0.001). Serum creatinine (and estimated glomerular filtration rate) had correlated with smoking and regression analysis indicated smoking was associated with high levels of serum creatinine (r=0.323, p<0.001, and r2=104). Smoking was a predictor for high levels of uric acid (p<0.001, r2=0.093). Smoking is associated with an increased inflammation status driven by changes in the immune response. The basic inflammation indices SII, NLR, and PLR, which can be derivated from whole blood count, and additionally CRP may be useful in the assessment of the inflammation status of smokers. [ABSTRACT FROM AUTHOR]

In this study, adhesive wear of woven E-Glass fabric reinforced composites filled with aramid, B4C and mica particles at 0.5% wt. and 1.5% wt. ratios were carried out under dry sliding conditions. The effects of filler type, applied loads (5, 10 and 15 N) and sliding distances (250, 500 and 750 m) on the tribological behavior of the composites were investigated on the pin-on-disc device. As a result of the studies, it was determined that the friction coefficient in aramid reinforced composites was lower than the other reinforced composites. In wear volume due to wear, it was observed that the aramid wear volume was less. In addition, Wear volume increased with increasing load for all particle reinforcements. But, the highest wear volume occurred in the neat wear sample at 15 N load conditions. For the wear rate and wear volume, the fillers have shown improvement up to 1.5% wt. in the composite. 1.5% wt. aramid-filled glass fiber woven composites showed the lowest wear rate: 2.82 × 10−4 mm3/N-m (at 15 N normal load). In addition, in the scanning electron microscope images taken, it was observed that there were breaks in the size of 15.07 µm in the epoxy and 61.11 µm in the fibers. The use of aramid with particle reinforcement rather than fiber is important for wear. In addition, the lowest wear volume was 65% more resistant at 1.5% wt aramid reinforcement and at 15 N load compared to the unreinforced composite in the abrasion tests. [ABSTRACT FROM AUTHOR]

Strengthening, heat treating, or rolling these alloys with different reinforcement particles positively affects the physical, mechanical and tribological properties. In this study, materials were produced by squeeze casting method by adding B4C particle to Al7075 alloy matrix in 4 different reinforcement ratios (4%, 8%, 10%, 12%). The physical, mechanical, and tribological properties of B4C/Al7075 composites were compared to the Al7075 alloy. In addition, aging and rolling processes were applied to B4C reinforced composite and Al7075 alloy, where the best mechanical properties were obtained, and the effects of these processes on hardness, tensile and flexural strengths, and tribological properties were investigated. The fracture and wear surfaces of the samples were investigated by SEM. When the effect of reinforcement ratio was examined, the highest hardness value was seen at 12% reinforcement ratio. The highest tensile and flexural strength was obtained from 10% reinforcement. Tensile strength of 10% B4C/Al7075 composite material was determined as 249 MPa and flexural strength as 494 MPa. As in the hardness value, the best value in wear resistance was obtained from 12%. B4C reinforcement increased the wear resistance of the Al7075 alloy. When the effect of aging was examined, it was observed that the determined properties of the materials were considerably improved depending on the aging period, but they partially decreased after a certain aging period. The rolling process also improved the determined properties of the materials, but this effect was not as high as in the aging process. [ABSTRACT FROM AUTHOR]