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In recent years, studies on the development of new and advanced composite materials have been increasing. Among these new technological products, Fiber Metal Laminates (FML), and hybrid structures made of aluminium, carbon, glass or aramid fiber, are preferred especially in the aircraft industry due to their high performance. Therefore, free vibration analysis is necessary for the design process of such structures. In this study, the vibration characteristics of FML for clamped-free boundary conditions were investigated experimentally and numerically. Firstly, numerical results were obtained using Finite Element Method (FEM) and then these results were compared with the experimental results. It was seen that the numerical results were in good agreement with the experimental results. As the theoretical model was justified, the effects of various parameters such as number of layers, fiber orientations, and aluminium layer thickness on the in-plane vibration characteristics of the FML straight beam were analysed using FEM. Thus, most important parameters affecting the vibration characteristics of the hybrid structures were determined.

The main sources of human exposure to trace metals for non-occupationally exposed individuals are inhalation and ingestion. Because the absorption rates of the metals by inhalation are significantly higher (up to 50-60%) than those by ingestion (between 3% and 10%), determination of trace metals in ambient air samples is of special interest. The main purpose of this study was to determine Fe, Zn and Cu in ambient air by combining pre-concentration methods and flame atomic absorption spectrophotometer (FAAS). In the pre-concentration step, adsorption reagents including 4-(2-pyridyl-azo) Resorcinol (PAR)-loaded XAD-7, thioureasulphonamide polymeric resin and cupferron-activated carbon were used sequentially. Under the optimum conditions, seasonal distributions of Fe, Zn and Cu concentrations in ambient air of Elazig City, Turkey, were determined. Concentrations of Fe, Zn and Cu were found to be in the ranges of 154-416, 101-323 and 12-75 ng/m³, respectively. High Zn levels determined in March and April can be attributed to the burning of coal at the beginning of spring. [ABSTRACT FROM AUTHOR]

BACKGROUND: To improve clinical outcomes, noninvasive imaging modalities have been proposed to measure and monitor atherosclerosis. Endothelial dysfunction is considered the first stage in the development of atherosclerosis. Brachial artery flow-mediated dilatation (FMD) has been impaired in patients with coronary slow flow (CSF). Recently, color M-mode derived propagation velocity of descending thoracic aorta (aortic propagation velocity-AVP) was shown to be an ultrasonographic marker for atherosclerosis. AIM: To assess endothelial function in patients with CSF and the correlation of AVP with FMD. MATERIALS AND METHODS: FMD and AVP were measured in 90 patients with CSF and 39 patients having normal coronary arteries (NCA) detected by coronary angiography. RESULTS: Compared to patients with normal coronary arteries patients having CSF had significantly lower AVP (39.1±8.4 vs. 53.7±12.7 cm/s, p < 0.001) and FMD (5.6±3.2 vs. 17.6±4.4 %, p < 0.001) measurements. There were significant correlations between AVP and FMD (r = 0.524, p < 0.001). CONCLUSIONS: Transthoracic echocardiographic determination of color M-mode propagation velocity of descending aorta is a simple practical method and correlates well with coronary slow flow and brachial endothelial function. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study is to evaluate whether there is a difference in serum soluble free acid synthesis (sFas) / sFasL levels between patients with preeclampsia, severe preeclampsia and normal healthy pregnancy. Methods: This is a case control study comparing serum sFas and sFasL concentrations in patients with mild preeclampsia (n=26) and patients with severe preeclampsia (n=22) in the second and the third trimester pregnancy to normal healthy pregnant controls (n=21). Maternal serum sFas and sFasL was collected at the time of diagnosis of preeclampsia or severe preeclampsia and obtained using ELISA assay. The control group’s characteristics of gestational age, maternal age, BMI, parity, smoking status, and history of hypertension were matched with the study groups. While evaluating the results, mean±SD for quantitaive data, the statistical methods of Kruskal Wallis and Mann- Whitney U tests for comparements between groups were used. Results: Maternal mean serum levels of sFas and sFasL were evaluated and statistical difference was not found in both preeclamptic pregnancies (846,65±96,74pg/ml and 17,48±15.60 pg/ml) and severe preeclamptic pregnancies ( 864,29±106,30 pg/ml and 99,92±336,69 pg/ml) versus control group (830,58±127,21 pg/ml and 30,13±22,69 pg/ml). For all demographic characteristics, there was also no statistical difference between study groups and control group. Conclusions: The finding of this study showed no difference in maternal serum levels of sFas and sFasL in preeclampsia and severe preeclampcia versus control group. [ABSTRACT FROM AUTHOR]

This experiment was designed to investigate the effect of sildenafil citrate on testicular injury after unilateral testicular torsion/detorsion (T/D). Thirty-seven adult male Wistar albino rats were divided into four groups: sham operated group (group 1), T/D+ saline (group 2), T/D+ 0.7 mg sildenafil citrate (group 3) and T/D+ 1.4 mg sildenafil citrate (group 4). Testicular torsion was created by rotating the right testis 720° in a clockwise direction for 2 h in other groups, except for group 1, which was served as sham group. The level of GSH ( P < 0.05) in the testis in the group 2 were significantly lower ( P < 0.05) and the levels of MDA and NO ( P < 0.01 for both) in the testis were significantly higher when compared with those of the group 1. Administration of low dose sildenafil citrate prevented the increases in MDA and NO levels and decreases in GSH values induced by testicular torsion. However, administration of high dose sildenafil citrate did not have any effect on these testicular tissue parameters ( P > 0.05). Also, mean values of seminiferous tubules diameters, germinal cell layer thicknesses and mean testicular biopsy score were significantly better in group 3 than groups 2 and 4. These results suggest that T/D injury occurred in testis after unilateral testicular T/D and that administration of low dose sildenafil citrate before detorsion prevents ischemia/reperfusion cellular damage in testicular torsion. Sildenafil citrate probably acts through reduction of reactive oxygen species and support antioxidant enzyme systems. [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluated the degree of adhesion formation and determined the uterine tissue malondialdehyde (MDA), nitric oxide (NO) and reduced glutathione (GSH) contents. The activities of catalase (CAT) and glutathione peroxidase (GPx) in an intraperitoneal adhesion model in adult rats receiving or not intraperitoneal installation of heparin or pentoxifylline were monitored. The results of the study showed that heparin and pentoxifylline can limit surgery-induced oxidative stress and regulate the inflammatory reaction, and heparin is more efficient than pentoxifylline in terms of preventing the intra-abdominal adhesion formation.

We report the case of a demyelinating lesion located in the left cerebellar region that developed 3 months after the onset of oral isotretionin treatment. In April 2001, 1 year before admission, the patient underwent cranial magnetic resonance imaging (MRI) because of endocrinological problems. This was found to be completely normal. In January 2002, oral isotretinoin treatment was started to treat severe acne. Three months after the onset of therapy, the patient reported lack of appetite, faintness and tinnitus. Her second cranial MRI scan showed a cerebellar lesion, and oral isotretinoin treatment was stopped (April 2002). One month after the cessation of oral isotretinoin treatment, the lesion became less prominent on the MRI scan, and after 3 months, it had disappeared. Although it is difficult to determine the causal association between the demyelinating cerebellar lesion and isotretinoin treatment, we would like to alert physicians to this possibility, because of the common usage of this drug in daily practice. [ABSTRACT FROM AUTHOR]

Abstract: The stress states encountered in ion implanted materials are often complicated, and, so analysis, and hence presentation thereof, is incomplete due to unavailability of computational and visual tools. Stress states determined by X-ray and neutron diffraction are usually calculated from the gradient of sin2Ψ curves. This process, inter alia, contracts the stress to a scalar, losing the directionality and multivariate nature of the real stress state. In this paper we present a novel approach to the stress profile analysis and presentation obtained by X-ray diffraction. Stress is considered as a tensorial quantity, from the initial measurement phase to the final presentation. This discussion inherently brings in the depth resolution of stresses, which in turn are explained by means of clear visual explanations. Visual tools, which are not common use in the field, are introduced and the benefits as applied to ion implantation are discussed. [Copyright &y& Elsevier]

A method for the separation and preconcentration of Cr(III) and Cr(VI) on activated carbon in presence of diethyldithiocarbamate as a complexing reagent was optimized. The method makes it possible to achieve 200- to 500-fold Cr(VI) concentrating depending on the initial volume of the solution to be analysed and the final volume eluted. The Cr(VI) concentration in the background solution determined with RSD 30% was equal to 1.5 μg L. The limit of Cr(VI) determination was equal to 0.9 μg L. [ABSTRACT FROM AUTHOR]

Summary. This study aimed to compare the diagnostic value of testicular fine-needle aspiration (FNA) with open biopsy in infertile males with azoospermia or severe oligozoospermia and to evaluate the reliability of testicular sperm extraction by FNA. A total of 76 testes of 40 patients, 34 with azoospermia, four oligozoospermia and two patients who underwent orchidectomy as a result of cancer of prostate were included. Detailed clinical and laboratory examinations were performed and two semen analyses were obtained from each patient. A 20-ml 26 gauge 13-mm needle was used for FNA and smears were stained with May–Grunwald–Giemsa and Papanicolaou stain. An open biopsy was performed in each patient after FNA and the samples were stained with haematoxylen–eosin. Smears and histological stains were examined and compared under light microscopy by the same pathologist. In 69 of the 76 testes (90%) FNA cytology results agreed with the histology. In four testes, the aspirate was unsatisfactory and in three testes, spermatocytic arrest was found cytologically while subsequent biopsies revealed diffuse fibrosis. In 15 of 16 patients (93.7%) with normal and hypospermatogenesis, spermatozoa had been extracted by FNA. Spermatozoa could not be obtained after neither FNA nor open biopsy in the remaining 24 patients. Testicular FNA in infertile males is a simple, reliable and minimally invasive diagnostic tool. It is as effective as open biopsy for testicular sperm extraction and good results can be achieved in experienced hands. [ABSTRACT FROM AUTHOR]

The article reports on contamination of aluminum (AI) from cooking utensils and yogurt containers. The neurotoxicity of aluminum has been known for more than a century. It has been implicated as an etiological factor in some pathologies such as encephalopathy, bone disease and anemia related to dialysis treatment. In this study, aluminum concentrations in Turkish meals cooked in new and old aluminum and the various other cooking utensils were determined by flame atomic absorption spectrometry. In addition, Al amounts leached from yogurt fermented in various containers made from new and old aluminum, steel and boron glass were determined at the soured and fresh conditions.

Summary Objective This study aimed to investigate the rate of occupational sensitization to horse hair in grooms and whether occupational exposure to horse hair increases respiratory and allergic symptoms and affects lung function in grooms or not. Methods This is a cross-sectional study. Two hundred grooms were randomly selected among 1000 grooms working in Veliefendi Hippodrome of Istanbul. One hundred and twenty-five subjects agreed to enter the study. Ninety-two workers who worked in the different parts of this hippodrome enrolled as the control group. A detailed questionnaire including respiratory and allergic symptoms was filled in, physical examination, skin prick tests and pulmonary function tests were performed. Results Sensitization to horse hair was 12.8% in grooms and 4.3% in controls. The difference was statistically significant (P = 0.0035). Asthma was found in 14.4% of the grooms and 5.4% of the controls, allergic rhinitis in 42.4% of the grooms and 18.4% of the controls, allergic conjunctivitis in 35.2% of the grooms and 15.2% of the controls, and allergic skin diseases in 32.8% of the grooms and 13% of the controls. The differences were statistically significant ( P = 0.043, P = 0.0002, P = 0.001 and P = 0.0008, respectively). The means of FEV 1 , FEV 1 /FVC and FVC parameters were significantly lower in the groom group ( P = 0.006, P = 0.001 and P = 0.003, respectively). In the multivariate analysis, being in the groom group and working years were found to be predictive factors for impairments of lung function ( P < 0.001 and P = 0.002, respectively). Conclusion Occupational exposure to horse increases the sensitization to horse hair, induces asthma and allergic symptoms and also impairs lung functions. [ABSTRACT FROM AUTHOR]

The relationship between nutritional status and insulin-like growth factor binding protein-2 (IGFBP-2) gene expression in chickens was studied. Chickens (6 wk old) were food deprived for 2 d and then refed. IGFBP-2 mRNA in the brain was significantly decreased by food deprivation and levels did not increase when birds were refed for 24 h. Gizzard and hepatic IGFBP-2 mRNA levels were significantly increased by food deprivation and decreased by refeeding. Any nutrients tested decreased hepatic IGFBP-2 gene expression. In kidney, IGFBP-2 mRNA was detected but not influenced by food deprivation and refeeding. In another study, the influence of dietary protein source [isolated soybean protein vs. casein; crude protein (CP) 20%] and the supplementation of essential amino acids on IGFBP-2 gene expression of young chickens (5 wk old) was examined. The influence of feeding a low soybean protein diet (CP 5%) on tissue IGFBP-2 gene expression was also investigated. Hepatic IGFBP-2 mRNA was not detected in any group. Feeding the low protein diet for 7 d decreased brain IGFBP-2 mRNA level and increased gizzard IGFBP-2 level compared with chickens fed 20% protein diets. A significant interaction between protein source and amino acid supplementation was observed in gizzard IGFBP-2 mRNA level. In both casein-fed groups and in chickens fed 20% soybean protein diet without supplemental amino acids, the levels did not differ from one another or from the low protein diet-fed birds. The level was lower in chickens fed the amino acid-supplemented, 20% soybean protein diet. In conclusion, the response of IGFBP-2 gene expression to variations in nutritional status was rapid and different in several tissues of young chickens, which would help modulate the growth-promoting effect of circulating IGF-I by making the IGF-IGFBP complex. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate whether exposure to sunflower pollen (Helianthus annuus ) increases both sensitization and respiratory symptoms, and whether or not it affects lung functions in sunflower processing workers. Methods: The largest sunflower processing factories in the Thrace region of Turkey participated in this study. Workers from the units directly exposed to sunflower seed enrolled as the study group (n = 102) and workers who were not directly exposed to Helianthus annuus pollen (n = 102) were the control group. Detailed questionnaires covering respiratory and allergic symptoms were completed, and skin prick tests and lung function tests were performed. Results: We found a very high rate (23.5%) of sensitization to Helianthus annuus in the study group compared to the controls (P < 0.001). Logistic regression analysis showed that the risk of sensitization to H. annuus was increased 4.7-fold (odds ratio = 4.17, 95% confidence interval = 1.3–16.7) if subjects were exposed to sunflower pollen in the workplace. While asthmatic symptoms and allergic skin diseases were not different between the two groups, workers in the study group had a higher rate of allergic rhinitis and conjunctivitis (P < 0.05). We found that pulmonary function was significantly impaired in the study group (P < 0.01). Using a multivariate analysis model, inclusion in the study group was found to be a predictive factor for impairment of lung function (P = 0.002). Conclusions: We conclude that sunflower pollen has high allergenic potential, especially when there is close contact, and exposure to sunflower pollen in the workplace can result in impairment in lung function. [ABSTRACT FROM AUTHOR]

This article presents information related to trace metal composition in Keban dam lake. In the present time, the domestic wastewater and its sludge, sewage sludge, is a critical problem in regard to peoples life, and has different concentration of toxic metals. The determinations of lead, chromium, nickel and cadmium were carried out by means of FAAS after the treatment with activated carbon enrichment procedure for water samples. Calibration curves for sludge samples were obtained by using lead (0.25-1.5), chromium (0.2-1.0), nickel (0.25-2.0), and cadmium (0.03-0.3) solutions at mg/L levels.

An attempt was made to identify the iron species that is most responsible for plant-available Fe. Iron concentrations in fruit samples were determined by using flame atomic absorption spectrometry (FAAS). The soil samples related to these fruits were also analyzed for Fe by using various digestion and extraction reagents. The relation between the fruit-Fe and soil-extractable-Fe concentrations was examined to explain the Fe uptake of fruit from soil. The probable chemical forms of Fe in the soil were evaluated for the speciation of Fe. [ABSTRACT FROM AUTHOR]

Evaluates the nickel specification in soil and the relationship with its concentration in fruits. Percentage of nickel recovered from the fruit samples; Effect of magnesium on nickel absorbance; Relation between the changes at the nickel contents of the cherry and strawberry samples and soil nickle concentrations for all studied extractants.

1. The change in the rate of protein synthesis of different muscles, concentrations of plasma insulin, plasma insulin-like growth factor-I (IGF-I) and other plasma components were investigated after refeeding in fasted chicks. 5·2 g of the complete diet was refed. This was the maximum that could be force-fed with water. 2. The fractional synthesis rates (FSR) of breast (M. pectoralis major) and leg (M. gastrocnemius) muscles were measured after injection of L-\[2, 6-3H]phenylalanine. Plasma insulin and IGF-I concentration were determined by radioimmunoassay. 3. In the breast muscle, FSR was significantly reduced by 2-d fasting. The FSR had recovered completely after 1 h of refeeding and was maintained until 6 h. The change in FSR after refeeding was associated with the change in ribosomal efficiency (K[sub RNA]; absolute synthesis rate per unit RNA), while no change in ribosomal capacity (C[sub S]; RNA: protein ratio) was observed. 4. In the leg muscle, FSR was decreased by 2-d fasting and increased gradually toward 6 h after refeeding but did not reach the level of the fed control. In contrast to the breast muscle, no significant changes in C[sub S] and K[sub RNA] in the leg muscle were observed. 5. Plasma glucose concentration increased significantly at 1 h after refeeding but returned to the fasted level after 24 h. Plasma insulin concentration in chicks refed for 1 h was higher than in the fasted group. There was no significant change in plasma IGF-I concentration. 6. These results suggest that the FSR of breast muscle was more sensitive to refeeding than that of leg muscle which may be explained, in part, by differences in sensitivity to the change in circulating plasma insulin concentration after refeeding. [ABSTRACT FROM AUTHOR]

Effective marine park management and protection of coral reefs can only happen if managers have adequate knowledge of reef health and area. However, obtaining such information is labor intensive and difficult with limited funding and time. Reef Check Malaysia was engaged by Department of Marine Parks Malaysia to map the coral reefs surrounding Tioman Island Marine Park and document health status and site specific threats. To achieve this, we utilized the Reef Check survey method, a simple, rapid and holistic standardized reef monitoring protocol based on scientific principles. This method is suitable where funds and time are limited. A total of 95 sites surrounding Tioman Island were surveyed with the assistance of certified Reef Check EcoDiver volunteers and representatives from local stakeholders. This citizen science approach proved successful and generated a baseline map revealing a difference in the health of coral reefs between the west and east sides of Tioman Island, where the West had 50% on the East. Combined with data on indicator fish and invertebrates, as well as human and natural impacts, the results suggest that Tioman Island should be separated into three distinctive conservation priority zones to enhance management strategies of this marine park. This is an example of an innovative way to engage and involve local stakeholders in planning conservation and management strategies.

[Display omitted] • Full physics-based IT equipment CFD model is built. • Machine learning is integrated with detailed IT equipment CFD model to improve the CFD model accuracy at off-design conditions. • Novel approach for developing compact IT equipment models which can predict its power consumption, airflow demand, and exhaust air temperature is proposed. • The derived IT equipment compact model is validated with the experimental results. In most data centers, performance reliability is often ensured by setting the amount of airflow provided by the cooling units to substantially exceed that which is needed by the IT equipment. This overly conservative strategy requires additional energy expenditure, which inevitably results in a huge amount of energy being wasted by the cooling system. To eliminate adopting such wasteful policies, conducting proper management of airflow, temperature, and energy is critical. To that end, this work proposes a novel approach to developing a compact IT equipment model at off-design conditions. This model is designed to support thermal and energy management functions in data centers. The benefit of this model is that it can accurately predict not only the IT equipment power consumption, but also the amount of flowrate required for the equipment and the air temperature leaving the equipment. While the compact model's power consumption was derived as a function of CPU utilization, its flowrate demand and exhaust temperature were obtained from a dynamic detailed CFD model. Results from the compact model were validated with experiments where the maximum mismatch was found to be 5.7% in the outlet temperature field and 11.4% in flowrate. Compared to a state-of-the-art IT equipment compact model, the developed model was found to reduce the prediction error of the equipment's flowrate and outlet air temperature by up to 5.2% and 9.3 % that of the state-of-the-art IT equipment compact model, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel solution to facilitate adopting liquid cooling technologies is introduced. • Cooling capacity and data center power usage effectiveness are used to evaluate the heat exchanger performance. • The operating conditions effect on the heat exchanger performance is investigated. • Energy efficient hybrid cooled data center operation is investigated. With the remarkable surge in IT power densities and energy consumption, the data center industry is starting to adopt energy and thermally-efficient single-phase cooling technologies. For many legacy data centers worldwide, the lack of a primary chilled water source is a substantial barrier to adopting single-phase technologies. In this study, the necessity of having a facility chilled water source for deploying liquid cooling solutions is eliminated by introducing a solution that does not require bringing in any modification of the data center layout. This simple solution proposes integrating liquid to air heat exchangers with the floor tiles to eject heat from the liquid-cooled IT equipment into the room air. An experimentally validated CFD modeling approach is used to investigate the performance of these heat exchangers. Results show that by installing two heat exchangers in different cold aisles, a significant amount of cooling load is handled at the design point conditions. When they are tested under different operational conditions, the cooling capacity of these heat exchangers is shown to be sensitive to the supply air temperature. To overcome the operational constraints stemming from the supply air temperature, an alternative configuration with just one heat exchanger installed in the hot aisle is considered and discussed. Results indicate that the second configuration shows superior performance to the first one in terms of sensitivity to supply air temperature and cooling capacity. Lastly, with this configuration, the data center utilizes energy extremely efficiently and achieves a power usage effectiveness of 1.06. [ABSTRACT FROM AUTHOR]

The polyphenol content of propolis has received a lot of attention due to the benign biological properties noted in the chemical composition studies. However, there are very limited studies about other chemical components found in trace amounts in nature which contribute to the therapeutic properties of propolis. The present study, therefore, investigated the amino acid and vitamin composition of propolis. Propolis harvested by 60 colonies of Apis mellifera caucasica belonged to local non-migratory beekeepers. The A. m. caucasica is known for its distinctive propolis collecting capability which native to the secluded Ardahan Province of Turkey. Vitamin (Thiamine, Riboflavin) combinations of propolis were determined using the HPLC (High-Performance Liquid Chromatography) fluorescent detector. An amino acid analysis was also performed with the UFLC (Ultra-Fast Liquid Chromatography) system consisting of binary pump and UV/VIS. Our findings record that the vitamin and amino acid content of propolis samples collected from three areas of different altitudes in the same region differed from each other. Vitamin B1 content and Vitamin B2 content ranged between 0.025-0.16 mg/100g, and 0.304-0.777mg/100g, respectively. A maximum amount of amino acid was reported as leucine, while a minimum amount of amino acid was seen as tryptophan in Ardahan propolis. Consequently, the vitamin and amino acid content of propolis, which derived from secondary plant metabolites of resin, varied depending on their geographical altitudes. Those vitamin and amino acids found in the propolis composition are believed to have beneficial therapeutic properties.

Equine glutathione transferase A3-3 (EcaGST A3-3) belongs to the superfamily of detoxication enzymes found in all higher organisms. However, it is also the most efficient steroid double-bond isomerase known in mammals. Equus ferus caballus shares the steroidogenic pathway with Homo sapiens, which makes the horse a suitable animal model for investigations of human steroidogenesis. Inhibition of the enzyme has potential for treatment of steroid-hormone-dependent disorders. Screening of a library of FDA-approved drugs identified 16 out of 1040 compounds, which at 10 μM concentration afforded at least 50% inhibition of EcaGST A3-3. The most potent inhibitors, anthralin, sennoside A, tannic acid, and ethacrynic acid, were characterized by IC50 values in the submicromolar range when assayed with the natural substrate Δ5-androstene-3,17-dione.