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In this study, mechanical testing of glass bead (GB), glass fiber (GF), and hybrid (GB/GF) composites was carried out. Following that, drilling tests were undertaken on glass bead/fiber-reinforced hybrid Polyamide 66 (PA66) polymer composites. The purpose of this study is to determine the mechanical properties of the cutting elements and the effect of cutting parameters (spindle speed and feed rate) and reinforcement ratios on thrust force and surface roughness (Ra). The contribution of the cutting parameters to the investigated outcomes was determined using statistical analysis. Optical microscopy and scanning electron microscopy (SEM) was used to inspect the hole quality and damage mechanisms. The results revealed that the feed rate was the most contributing factor to thrust force (96.94%) and surface roughness (63.59%). Furthermore, in comparison to other hybrid composites, the lowest Ra value was obtained as 0.95 µm in samples containing 30% GB, while the Ra value was 1.04 µm in samples containing 10% GF + 20% GB. Polymer PA reinforced with 30% GF had the highest strength, modulus of elasticity, impact strength, and hardness.

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This study investigates the effects of human capital, bio-capacity, energy use, and economic growth on the ecological footprint of G20 countries for the period 1970-2016, using the panel dynamic common correlated effects (DCCE) model. In the study, the G20 was considered in two groups, as developed and emerging economies. According to the DCCE estimation results, the long-term impact of human capital on the ecological footprint is negative and statistically strong in the developed economies while it is insignificant in the emerging economies. The impact of bio-capacity on the ecological footprint is positive in the short and long term in the emerging economies, and only in the short term in the developed economies. In addition, economic growth and energy use undermine the environmental quality in both groups of countries. The error correction coefficients are negative and statistically significant, which means that the deviations from the short-term equilibrium converge the long-term equilibrium level for both groups.

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Evaluation of personal protective equipment is a very demanding task in designing an effective workplace safety programme. There is variable equipment to prevent job accidents, to protect workers' health and safety and to minimize the damage of any possible accident. Comparing the alternatives for the most favourable equipment, e.g. possible high noise levels, is one of the most difficult issues to deal with. In this study, the analytic hierarchy process method allows selection of personal protective equipment analytically, which is used to decide on efficient personal protection equipment when choosing protective shoes, helmets, earmuffs and dust masks.

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OBJECTIVES: Small dense (sd) low-density lipoprotein (LDL), tumor necrosis factor (TNF) alpha (α), and nitric oxide (NO) have recently emerged as important stroke risk factors. The aim of the study was to investigate the effects of increased levels of small LDL particle size, TNF-α and NO on the developed ischemic stroke and increased carotid artery intima-media thickness (CIMT). MATERIALS AND METHODS: A total of 29 women and 25 men (a total of 54 ischemic stroke patients) and a similar age group of 50 controls (29 females and 21 males) were included in the study. CIMT, C-reactive protein (CRP), TNF-α, NO, and lipid subfraction test of the two groups were measured. RESULTS: The mean LDL particle size was smaller in patients with stroke than in the controls (26.8 ± 0.31 nm vs. 27.0 ± 0.31 nm, P = 0.003). sd-LDL, TNF-α, NO, CRP, right CIMT, and left CIMT were higher in patients with stroke than in the controls (respectively; 8.2 ± 7.8 mg/dL vs. 3.3 ± 3.5 mg/dL, P < 0.001;75.6 ± 25.0 pg/mL vs. 65.4 ± 9.1 pg/mL, P = 0.009;76.4 ± 53.3 mmol/L vs. 41.5 ± 27.0 mmol/L, P < 0.001;1.9 ± 2.6 mm vs. 0.4 ± 0.3 mm P < 0.001;0.97 ± 0.38 mm vs. 0.83 ± 0.15 mm, P = 0.007;1.04 ± 0.44 mm vs. 0.87 ± 0.19 mm, P = 0.010). CONCLUSION: These results show that sd-LDL is independently associated with the incidence of stroke and may be a risk factor in the development of stroke. In addition, TNF-α, NO, right CIMT, and left CIMT may be a risk factor in the development of ischemic stroke.

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OBJECTIVE: Metabolic syndrome plays a significant role in the development of benign prostate hyperplasia (BPH) and overactive bladder (OAB). Non-alcoholic fatty liver disease (NAFLD) is accepted as the hepatic component of metabolic syndrome. This study investigated the association of NAFLD with BPH and OAB. MATERIAL AND METHODS: In total, 702 men with BPH and 529 women with and without OAB were recruited into the study in a cross-sectional risk factor analysis. All male and female patients were separated into two groups, with or without NAFLD. An overnight fasting blood profile was obtained and whole abdominal ultrasound was performed by a blinded radiologist in each patient to measure hepatic steatosis. RESULTS: NAFLD was diagnosed in 387 (55.8%) of 702 men with BPH. Statistically significantly higher prostate volumes were found in men with NAFLD in comparison to without (p = 0.018). The female population included 207 women with NAFLD and 322 women without. OAB was found in 75.8% and 52.4% of women with and without NAFLD (p = 0.022). CONCLUSIONS: NAFLD is associated with BPH in men and with OAB in women. These findings confirm the hypothesis that BPH is an aspect of the metabolic syndrome and support the hypothesis that OAB is an aspect of the metabolic syndrome.

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