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Aluminum, boron, and magnesium are one of the most common aerospace infrastructure materials. Therefore it is important to know their effectiveness in radiation shielding. In this study, Al–B–Mg powder alloy with a nominal composition of Al50B25Mg25 was synthesized by using a mechanical alloying (MA) process under an argon gas atmosphere for potential use as a aluminum based engineering material. Microstructural evolution, thermal behaviour, and mechanical properties of the mechanically alloyed powders as a function of milling time were investigated by means of X-ray diffraction (XRD), differential scanning calorimetry, transmittance electron microscopy and scanning electron microscopy (SEM). The XRD and SEM results revealed that the microstructure of the powders materials changed during MA. The crystallite size of Al–B–Mg powders decreased with increasing milling time. The average crystallite size was determined. The results also showed that after 100 h of milling time nanostructured α-Al (Mg, B) solid solution phase whose crystallite sizes are below 17 nm were obtained. Also, radiation shielding parameters have been investigated using NaI (Tl) γ-ray spectrometry at 662 and 1173 keV energies obtained via 137Cs and 60Co radioactive point sources. The obtained experimental data have been compared with XCOM theoretical data. The experimental data was utilized to calculate the half-value layer, tenth-value layer, and mean free path values. According to the obtained data, Al50Mg25B25 alloy powder prepared and annealed at 300 °C has been shown to provide better protection against radiation.

Background. This study aimed to compare the in vitro cytotoxicity of Theracal LC, BiodentineTM, iRoot BP Plus, and MTA Angelus on human pulp fibroblasts (HPF). Methods. Fifteen discs from each calcium silicate-based material were prepared in sterile Teflon molds. After setting, the fabricated discs were eluated with a culture medium for 24 h. HPF cells were plated onto 24-well plates at 5×103 cells/well, and the cells were exposed to the material eluates. The cell viability was evaluated with MTT assay at three different times (24, 48, and 72 h). Data were statistically analyzed. The apoptotic/necrotic status of HPF cells exposed to material eluates was determined by flow cytometry. Results. The differences between the effects of Theracal LC, BiodentineTM, MTA Angelus, and iRoot BP Plus on HPF cells were found to be statistically significant (PConclusion. Based on the results of the present study, BiodentineTM, MTA Angelus, and iRoot BP Plus can be classified as biocompatible materials in vital endodontic treatments. However, the Theracal LC materials should be used carefully due to their cytotoxic effects.

A series of La and Y rates of Mg65Ni20Y15−xLax (X = 1, 2, 3) alloys was synthesized by mechanical alloying in order to investigate the influence of varying amounts of Y and La on the microstructure and degradation performance of methyl blue. The nano-structured alloys were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry (EDX), UV–Vis spectroscopy (UV) and Fourier-Transform Infrared Spectroscopy (FTIR) techniques. Three different intermetallic phases such as Mg24Y5, Mg17La2 and Mg2Ni were obtained after 75 h of milling time. With an increase in the milling time, the particle and crystallite size of the Mg65Ni20Y15−xLax (X = 1, 2, 3) powders were decreased and the crystallite sizes of the alloys were calculated below 20 nm after 75 h of milling time. The composition of the nanostructured powders after mechanical alloying were determined to be very close to the initial composition by EDX analyses. The time and amount-dependent photocatalytic degradation of methyl blue samples were investigated under visible light at room temperature. The photocatalytic degradation properties of methyl blue in the water samples were evaluated by recording the decrease of absorbances at 590 nm in UV–Vis absorption spectra. The nanostructured Mg65Ni20Y15−xLax (X = 1, 2, 3) powders demonstrated highly efficient photocatalytic properties in daylight even in the absence of any oxidant, heat or light source. After a 30 min exposure, the UV–Vis and FT-IR spectra indicated that the methyl blue samples became colourless using Mg65Ni20Y15−xLax (X = 1, 2, 3) type catalysts. Among the alloys, the Mg65Ni20Y13La2 is the best catalyst for the photocatalytic degradation of methyl blue possibly because of it had the smallest crystalline size compared to the other alloys.

Aim: Ankylosing spondylitis (AS) is a chronic disease featuring axial changes, peripheral arthritis and systemic involvement. AS is not only characterized by the strongest genetic contribution for any complex rheumatological disease but is also influenced by environmental and immunological factors. Various proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin- (IL-) 1, IL-6, IL17/28 are probably involved in AS pathogenesis. Recent years IL -23 / IL-17 pathway in the disease pathogenesis has been shown. Bilirubin (Bb) was known to be the end product of hem catabolic pathway, but it was the subject of various studies with antioxidant, anti-inflammatory and immunomodulatory properties in the last decade. Here, the clinic importance of serum Bb parameters in AS patients has been analyzed.Methods: The study designed as case-control. One hundred (N=100) patients with axial AS diagnosed by 2010 Assesment in Ankylosing Spondylitis International Society (ASAS) Classification Criteria were included to the study. Control group was consisted of 75 patients of similar age, gender and BMI. Participants' age, gender, body mass index (BMI), disease acitivity scores and laboratory data were recorded from the hospital data. Disease activity evaluated by Bath Ankylosing spondylitis disease activity index (BASDAI), Bath Ankylosing spondylitis functional index (BASFI) and Ankylosing spondylitis disease activity score-C-reactive protein (ASDAS_CRP). For these three scores, automatic calculation formulas were used on Internet. ASDAS_CRP>3.5 were accepted as cut-off value for high disease activity. Serum direct Bb, indirect Bb, total Bb, aspartat aminotransferase (AST), alanin aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma glutamyl transferase (GGT), amylase, lipase, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values were recorded from the hospital records.Results: The study included 100 AS patients at mean age of 37.9 ± 12 years, 75 controls at mean age of 39.2 ± 5.2 years. There was no significant difference between the two groups in terms of age (p = 0.12), gender (p = 0.32), and BMI (p = 0.067). In the AS group, ESR (p< 0.001), CRP (p < 0.001), uric acid (p 3.5, direct Bb (p = 0.020), total Bb (p = 0.029) and AST (p = 0.004) were significantly lower in high activity group (N = 25) and ESR (p = 0.000) was significantly higher.Conclusion: The direct Bb in patients with AS were found significantly low and negatively correlated with disease activity, this supports the role of oxidative stress in AS disease pathogenesis. Bb can be used as a biomarker in diagnosis and follow up in AS disease., Amaç: Ankilozan spondilit (AS) aksiyal değişiklikler, periferik artrit ve sistemik tutulum içeren kronik bir hastalıktır. AS herhangi bir komplike romatizmal hastalık gibi sadece en güçlü genetik katkı ile karakterize edilmez, aynı zamanda çevresel ve immünolojik faktörlerden de etkilenir. Tümör nekroz faktörü (TNF), interlökin- (IL-) 1, IL-6, IL17 / 28 gibi çeşitli proinflamatuar sitokinler muhtemelen AS patogenezinde rol oynar. Son yıllarda hastalık patogenezinde IL-23 / IL-17 yolu gösterilmiştir. Bilirubin (Bb) hem katabolik yolun son ürünüdür hem de son on yılda antioksidan, antienflamatuar ve immünmodülatör özellikleri olan çeşitli çalışmaların konusu olmuştur. Burada AS hastalarında serum Bb parametrelerinin klinik önemi analiz edilmiştir.Yöntemler: Çalışma vaka-kontrol olarak planlandı. Uluslar arası Ankilozan Spondilit Topluluğu 2010 Sınıflandırma Kriterleri'ne göre (ASAS) aksiyal AS tanısı almış 100 hasta (N = 100) çalışmaya dahil edildi. Kontrol grubu benzer yaş, cinsiyet ve VKİ olan 75 kişiden oluşmaktaydı. Katılımcıların yaş, cinsiyet, vücut kitle indeksi (BMI), hastalık skoru puanları ve laboratuvar verileri hastane verilerinden kaydedildi. Hastalık aktivitesi Bath Ankilozan Spondilit Hastalığı Aktivite İndeksi (BASDAI), Bath Ankilozan Spondilit Fonksiyonel İndeks (BASFI) ve Ankilozan Spondilit Hastalığı Aktivite skoru-C-reaktif protein (ASDAS_CRP) ile değerlendirildi. Bu üç puan için, internette otomatik hesaplama formülleri kullanıldı. ASDAS_CRP> 3,5 yüksek hastalık aktivitesi için eşik değer olarak kabul edildi. Serum direkt Bb, indirekt Bb, total Bb, aspartat aminotransferaz (AST), alanin aminotransferaz (ALT), alkalen fosfataz (ALP), laktat dehidrojenaz (LDH), gama glutamil transferaz (GGT), amilaz, lipaz, eritrosit sedimentasyon hızı (ESR) ve C-reaktif protein (CRP) değerleri hastane kayıtlarından kaydedildi.Bulgular: Çalışmaya yaş ortalaması 37,9 ± 12 yıl olan 100 AS hastası, yaş ortalaması 39,2 ± 5,2 yıl olan 75 kontrol alındı. İki grup arasında yaş (p = 0.12), cinsiyet (p = 0.32) ve VKİ (p = 0.067) açısından anlamlı fark yoktu. AS grubunda ESR (p < 0.001), CRP (p< 0.001), Bb (p = 0.016) anlamlı düşük; ürik asit (p< 0.001) kontrollerden anlamlı olarak yüksek bulundu.Korelasyon analizinde, Bb parametreleri ve hastalık aktivite parametreleri birbirleriyle negatif korelasyon göstermiştir. ASDAS_CRP> 3,5'e göre gruplandırıldığında, direkt Bb (p = 0,020), total Bb (p = 0,029) ve AST (p = 0,004) yüksek aktivite grubunda (N = 25) anlamlı düşük; ESR (p

PubMedID: 27828634 Background: Psoriasis is a multigenic and multifactorial dermatological disease linked to cardiovascular diseases. Increased levels of homocysteine in patients with psoriasis have been demonstrated in many studies. The most frequently investigated genetic defect that plays a role in homocysteine metabolism is single point substitution (C to T) located on the 677th nucleotide of the methylenetetrahydrofolate reductase gene (MTHFR). Objective: In this study, we aimed to investigate methylenetetrahydrofolate C677T polymorphism in psoriasis patients in Turkey. Methods: The study included 96 patients with psoriasis and 77 controls from southern Turkey. Methylenetetrahydrofolate C677T polymorphism was analysed using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism methods. Results: In the psoriasis group, 34 CC (35.4%), 46 CT (47.9%) and 16 TT (16.7%) genotypes were found, respectively; while in the control group, the figures were 39 (50.6%), 35 (45.5%), 3 (3.9%). Homozygote and heterozygote T alleles of methylenetetrahydrofolate C677T polymorphism were significantly higher in the psoriasis than in the control group (p=0.013). Conclusion: We firstly found a correlation between methylenetetrahydrofolate C677T polymorphism and psoriasis among the southern Turkish population. © 2016 by Anais Brasileiros de Dermatologia.

Background/Aims: Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which catalyzes the formation of reactive oxygen species (ROS) in phagocytic cells, has five subunits: p67phox ("phox"refers to "phagocyte oxidase"), p47phox, p40phox, p22phox, and gp91phox (catalytic subunit). Oxidative stress resulting from the accumulation of ROS and/or defective removal of ROS by antioxidants has detrimental effects on cellular functions and may contribute to chronic inflammation. Disruption of the colonic mucosa due to the dysregulation of antioxidants or transformation enzymes may play a role in the pathogenesis of ulcerative colitis (UC) and influence the clinical features of this disease. In this study, we examined the expression of the gene encoding NADPH oxidase subunit p22phox cytochrome b-245, alphapolypeptidein the colonic mucosa to test its possible contribution in the pathogenesis of UC.Materials and Methods: Expression levels of mRNA in the inflamed and non-inflamed colonic mucosa (determined using colonoscopy)of 22 patients with UC and in the normal mucosa of 22 healthy controls were analyzed using real-time polymerase chain reaction.Results: Expression levels of mRNA were not significantly different between patients with inflamed and non-inflamed colonic mucosa (p>0.05) and betweenpatients with inflamed colonicmucosa and healthy controls (p>0.05). Conclusion: Although our data suggest that expression of the gene encoding p22phox is not associated with chronic inflammation in patients with UC, other mechanisms can affect oxidative stress in these patients.

The effect of biomass share on gaseous pollutant emissions from fluidized bed co-firing of various biomass fuels with high calorific value coals have extensively been investigated to date. However, effect of co-firing of olive residues with low calorific value lignites having high ash and sulfur contents has not been studied in bubbling fluidized bed combustors. In this study, experimental results of various runs pertaining to gaseous emissions (O2, CO2, CO, SO2, NO, N2O) from METU 0.3 MWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig co-firing olive residue with indigenous lignite at different biomass shares are presented. The results reveal that co-firing increases combustion efficiency irrespective of the biomass share and that increase in biomass share reduces N2O and SO2 emissions considerably while increasing CO emission. O-2, CO2 and NO emissions are not found sensitive to increase in biomass share. Olive residues are co-fired with high ash and sulfur containing lignite without any operational problems.

OBJECTIVE: Nitric oxide is produced by endothelial nitric oxide synthase, and its production can be influenced by polymorphisms of the endothelial nitric oxide synthase gene. Because candidate genes responsible for susceptibility to ankylosing spondylitis are mostly unknown and available data suggest that there may be problems related to the nitric oxide pathway, such as endothelial dysfunction and increased asymmetric dimethylarginine, this study aimed to assess the association of common endothelial nitric oxide synthase gene polymorphisms with ankylosing spondylitis. METHODS: One hundred ninety-four unrelated Turkish ankylosing spondylitis patients and 113 healthy without apparent cardiovascular disease, hypertension or diabetes mellitus were included. All individuals were genotyped by PCR-RFLP for two single-nucleotide polymorphisms, namely 786T>;C (rs2070744, promoter region) and 786 Glu298Asp (rs1799983, exon 7). Variable numbers of tandem repeat polymorphisms in intron 4 were also studied and investigated by direct electrophoresis on agarose gel following polymerase chain reaction analysis. The Bath ankylosing spondylitis metrology index of the patients was calculated, and human leukocyte antigen B27 was studied. RESULTS: All studied polymorphisms satisfied Hardy-Weinberg equilibrium. Sex distributions were similar between the patient and control groups. No significant differences were found in the distributions of allele and genotype frequencies of the studied endothelial nitric oxide synthase polymorphisms between patients and controls. There were no correlations between endothelial nitric oxide synthase polymorphisms, disease duration, Bath ankylosing spondylitis metrology index or human leukocyte antigen B27. CONCLUSION: The results presented in this study do not support a major role of common endothelial nitric oxide synthase polymorphisms in Turkish ankylosing spondylitis patients.

Meningitis is an inflammation of the protective membranes covering the brain and spinal cord caused by bacteria, fungi, or viruses with various clinical symptoms. Although meningitis is not so prevalent, it remains the most serious contagious disease. The aim of our study was to investigate the effect of gene expressions of nitric oxide synthases (NOS) on meningitis patients. Using samples taken from 61 meningitis patients, inducible NOS, endothelial NOS (eNOS), and neuronal NOS mRNA levels were assessed in both blood and cerebrospinal fluid (CSF). A control group was constructed of 64 healthy persons. The gene expression analysis was made using real-time polymerase chain reaction method. There was no neuronal NOS expression in either group, whereas inducible NOS expression was detected in 40 blood samples and 12 CSF samples from meningitis patients. However, there were no marked differences between groups (p=0.5104). eNOS expression was detected in all blood and CSF samples, which was markedly higher in patients (p=0.0367). Because the increase in eNOS expression increases NO production, eNOS expression in meningitis patients is of great importance. This increase of eNOS in meningitis patients compared with healthy subjects may lead to novel treatments for reducing the severity of the disease.

We have studied the multiple-point interactions of the pyranine (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt; 3sPyOH) fluoroprobe with polymer chains during the free-radical polymerization of acrylamide (AAm) by using the steady state fluorescence measurements. We observed a considerable blue shift from 515 nm to 406 nm in the emission spectra due to a C–O ether bond formation between the hydroxylic oxygen of 3sPyOH and a terminal C-atom of the growing AAm chain. Furthermore ionic (electrostatic) interactions occur between the three ionized sulfonic acid groups (SO3−) of 3sPyOH and protonated amide groups on the AAm chains. These electrostatic interactions also cause a gradual red shift in the maximum of the short-wavelength-peak, from 406 nm to 430 nm. The results showed that the pyranine can be used as a probe for real time monitoring of the polymerization process of AAm system since it monitors both the progression of the polymerization via chemical binding over OH group and the change in the local density of the polymerizing sample by means of the gradual red shift in the short-wavelength-peak via ionic interactions over SO3− groups.

A comprehensive model, previously developed and tested for prediction of behavior of continuous fluidized bed combustors is extended to incorporate NOx formation and reduction reactions and applied to the simulation of Middle East Technical University (METU) 0.3 MWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) burning lignites with high Volatile Matter/Fixed Carbon (VM/FC) ratios in their own ashes. Favorable comparisons are obtained between the predicted and measured temperatures and concentrations of gaseous species along the combustor. Results show that determination of partitioning of coal nitrogen into char-N and volatile-N, char combustion rate, and amount of volatile nitrogen released along the combustor are found to be the most important parameters that affect NO formation and reduction in bubbling fluidized bed combustors.

WOS: 000308422300007, PubMed ID: 22471835, Reduction in the synthesis or bioavailability of nitric oxide plays a significant role in the development of hypertension. Propolis is a resinous product collected by honeybees from various plant sources. Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the biosynthesis of catecholamines. The aim of this study was to examine the effect of propolis on blood pressure (BP), TH, and total RNA levels in the adrenal medulla, heart, and hypothalamus tissues in chronic nitric oxide synthase (NOS)-inhibited rats by N-w-nitro-L-arginine methyl ester (L-NAME). Rats received NOS inhibitor (L-NAME) for 15 days to produce hypertension and propolis for the last 5 days. TH activity and total RNA levels significantly increased in adrenal medulla, heart, and hypothalamus tissues in L-NAME-treated groups (P < .05). TH activity and total RNA levels of L-NAME+propolis-treated rats reduced (P < .05) compared with L-NAME-treated groups. TH activity in propolis-treated rats was reduced to the control values. L-NAME led to a significant increase in BP compared with the control group. Propolis administration to L-NAME-treated rats reduced BP but this was not statistically significant compared to L-NAME-treated groups. These results suggest that propolis decreases TH activity in NOS-inhibited hypertensive rats and thereby may modulate the synthesis of catecholamine and BP., Nigde University [BAP 2008/25], The Nigde University Research Fund (BAP 2008/25) is gratefully acknowledged for supporting this work. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Sulfur release and capture behavior of lignites with highly combustible sulfur-contents were investigated by extending a previously-developed comprehensive model to incorporate sulfur retention. The predictive performance of the model was tested by comparing the model predictions with on-line concentration measurements of O2, CO2, CO and SO2. Favorable comparisons are obtained between the predicted and measured concentrations of gaseous species along the combustor. Results show that freeboard sulfur-capture is enhanced significantly with recycling of elutriated sorbent particles as the sulfur release to the freeboard is significant for fuels rich in combustible sulfur.

Al-Si alloys with nominal composition of Al-8 wt. %Si, Al-12wt.%Si, and Al-16wt.%Si were rapidly solidified by using melt-spinning technique to examine the influence of the cooling rate/conditions on microstructure and mechanical properties. The microstructures of the rapidly solidified ribbons and ingot samples were investigated by the optical microscopy, electron microscopy and X-ray diffraction (XRD) techniques. The results showed that the structures of all melt-spun ribbons were completely composed of finely dispersed alpha-Al and eutectic Si phase, and primary silicon was not observed. The XRD analysis indicated that the solubility of Si in the alpha-Al matrix was greatly increased with rapid solidification. Additionally, mechanical properties of both conventionally cast (ingot) and melt-spun ribbons were examined by using Vickers indenter for one applied load (0.098 N). The hardness values of the melt-spun ribbons were about three times higher than those of ingot counterparts. The high hardness of the rapidly solidified state can be attributed to the supersaturated solid solutions. Besides, hardness values with different applied loads were measured for melt-spun ribbons. The results indicated that Vickers hardness values (H(v)) of the ribbons depended on the applied load. Applying the concept of Hays-Kendall, the load independent hardness values were calculated as 694.0, 982.8 and 1186.8 MN/m(2) for Al-8 wt.%Si, Al-12wt.%Si and Al-16 wt.%Si, respectively. (C) 2004 Elsevier B.V. All rights reserved.

A comprehensive model, previously developed and tested for prediction of behavior of continuous fluidized-bed combustors, is extended to incorporate char attrition and is applied to the simulation of a 0.3 MegaWatt (MW) atmospheric bubbling fluidized-bed combustor burning lignites with high Volatile Matter/Fixed Carbon (VM/FC) ratios in their own ashes. The effect of this incorporation is assessed by comparing the predictions of the model with and without attrition with measurements. Favorable comparisons obtained between predicted and measured temperature and concentration profiles and carryover char particle size distributions imply that these parameters are not sensitive to char attrition for lignites and the operating conditions under consideration. However, comparisons between combustion efficiencies predicted with and without char attrition and those obtained from measurements show that consideration of char attrition is essential for accurate prediction of combustion efficiencies.

The effect of recycle on gaseous pollutant emissions from fluidized-bed combustion of high-quality coals has extensively been investigated and is well documented. However, the effect of recycle on gaseous emissions from combustion of Turkish lignites with high ash, volatile matter, and sulfur contents has not been investigated to date. Recent trends in the utilization of indigenous lignites in fluidized-bed boilers necessitated investigation of pollutant emissions and adaptation of fluidized-bed combustion technology to these lignites. In this study, experimental results of various runs pertaining to gaseous emissions from the Middle East Technical University 0.3 MWt atmospheric bubbling fluidized-bed combustor test rig burning a typical indigenous lignite, Beypazari, at various recycle ratios, with and without limestone addition, are presented. Measurements show that the effect of recycle on already high combustion efficiency in once-through operation is not pronounced. As for the gaseous emissions, introduction of recycle reduces NOx and SO2 emissions but enhances CO emission.

Thymoquinone, one of the essential oil in the structure of cumin, is used for alternative therapy for many diseases from past to present. It was shown to have anti-carcinogenic and anti-inflammatory effects, as well as positive effects on fibrosis. However, there is no study on the effect of thymoquinone on cancer and fibrosis mechanism in bronchial epithelium cell line BEAS-2B. In our study, the effect of thymoquinone on cell viability and transforming growth factor-beta 1 (TGF-β1) level, which has an important role in the regulation of many biological processes including cancer and fibrosis-associated signal transduction, was evaluated. BEAS-2B cells were exposed to thymoquinone at 0–80 μmol/L concentrations for 24-, 48- and 72-hour durations. Cell viability was evaluated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. TGF-β1 level was determined with enzyme-linked immunosorbent assay (ELISA) method from the collected supernatant. Cell viability was found to be increased at all concentrations and durations (10–80 μmol/L; 24, 48 and 72 h) according to the control group (0 μmol/L; thymoquinone in ethanol) (p < 0.0001). Moreover, thymoquinone was found to increase the level of TGF-β1 only at 80 μmol/L concentration and 24-hour exposure period (0 μmol/L, 53.41 ± 18.44 pgr/ml TGF-β1; 80 μmol/L, 174.5 ± 80.03 pgr/ml TGF-β1). As a result, thymoquinone was found to increase cell proliferation and encourage TGF-β1 release.

This study presents the results from investigation of ash deposition characteristics of a high ash and sulfur content lignite co-fired with three types of biomass (olive residue, 49 wt%; hazelnut shell, 42 wt%; and cotton residue, 41 wt%) in 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustion (ABFBC) Test Rig. Deposit samples were collected on all air-cooled probe at a temperature of 500 degrees C. Samples were analyzed by SEM/EDX and XRD methods. The results reveal that co-firing lignite with olive residue, hazelnut shell and cotton residue show low deposition rates. High concentrations of silicon, calcium, sulfur, iron, and aluminum were found in deposit samples. No chlorine was detected in deposits. Calcium sulfate and potassium sulfate were detected as major and minor components of the deposits, respectively. High sulfur and alumina-silicate content of lignite resulted in formation of alkali sulfates instead of alkali chlorides. Therefore, fuel blends under consideration can be denoted to have low-fouling propensity. (c) 2008 Elsevier Ltd. All rights reserved.

There is very little work on the expression of TRPM6/7 in ischemia reperfusion models. In previous studies, after ischemia, reperfusion had been kept limited to 24 h, yet in our study, expressions of these channels were elucidated after its modification to 48 h to establish what kind of changes renal tissues undergo. For the current study, 20 Wistar albino rats were divided into two groups equally. Group I: control group, Group II = I/R group (60 min ischemia + 48 h reperfusion). For the mRNA analysis, right kidneys of I/R group was used as a reference in order to eliminate genetic differences. The left renal artery (I/R generated part) of I/R area was removed from all rats in the second group. Likewise, normal tissues of right renal artery were removed from all rats. Histopathologic scoring of the tissue samples were achieved semi-quantitatively according to normal tissue composition. Consequently, both TRPM6 and TRPM7 expression levels were decreased in all groups according to control groups, yet results were not counted as significant (p > 0.05). Additionally, correlation analysis confirmed these results. Also, I/R performed kidneys had more tissue damage compared to control group. To conclude, our study results suggest that TRPM6/7 expressions may be increased and after 48 h of reperfusion expression levels of these two stored to normal levels. At the same time, damages have occurred in renal tissues after ischemia. These damages were considered to be resulted from the oxidative effects as previously reported.

An improved version of a combustion-desulfurization model for fluidized bed combustors burning high ash and sulfur content low quality lignite in its own ash with the addition of limestone is presented. The desulfurization model considers sulfur retention by both limestone and ash and is based on first order catalyst deactivation where the kinetics of desulfurization is described by two rate constants; one for the initial surface reaction, the other for the rate of pore plugging or deactivation. The accuracy of the complete model with experimentally determined deactivation rate constants was tested by applying it to a 0.3 MWt AFBC test rig and comparing its predictions with measurements. Comparisons show that (he model produces reasonably accurate predictions of sulfur retention provided that the rate constants are determined experimentally under the fluidized bed combustor operating conditions.

This study describes the partitioning of 20 trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and eight major and minor elements (Al, Ca, Fe, K, Mg, Na, Si, Ti) during the combustion of high ash content lignite. The experiments were carried out in the 0.3 MW t Middle East Technical University (METU) atmospheric bubbling fluidized bed combustor (ABFBC) test rig with and without limestone addition. Inert bed material utilized in the experiments was bed ash obtained previously from the combustion of the same lignite without limestone addition in the same test rig. Concentrations of trace elements in coal, limestone, bottom ash, cyclone ash and filter ash were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). Partitioning of major and minor elements are influenced by the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Cr, Hg, Li, Mo, Ni, Sn, V, Zn) are recovered in fly ash. Limestone addition shifts the partitioning of Ba, Cr, Mo, Ni, Sn, V, Zn from bottom ash to fly ash.

The behavior of 20 trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 8 major and minor elements (Al, Ca, Fe, K, Mg, Na, Si, Ti) during the combustion of high ash content lignite with and without limestone addition have been investigated in the 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig. Experiments were performed without fines recycle. Inert bed material utilized in the experiments was bed ash obtained previously from the combustion of the same lignite without limestone addition in the same test rig. Concentrations of trace elements in coal, limestone, bottom ash, cyclone ash and filter ash were determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Measurements show that the distribution of major and minor elements follows the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Cr, Hg, Li, Mo, Ni, Sn, V, Zn) are recovered in fly ash. Comparisons between the trace element partitioning of the runs with and without limestone addition reveal that addition of limestone shifts the partitioning of Ba, Cr, Hg, Mo, Ni, Sn, V, Zn from bottom ash to fly ash.Copyright © 2005 by ASME

Synovial fibrosis is one of the main outcomes of osteoarthritis. Some authors have reported that urotensin-II (U-II) may cause pathologic fibrosis in cardiovascular system, lung and liver. However there are no previous reports available in the literature about its relationship with the synovial fibrosis in osteoarthritis. The aim of this study was to compare the U-II levels in knee synovial fluids obtained from osteoarthritic and non-osteoarthritic patients. Two groups were created, the osteoarthritis group and non-osteoarthritic control group. The control group was consisted of patients who underwent arthroscopic surgery for other reasons than cartilage disorders. In the osteoarthritis group all patients had grade 4 primer degenerative osteoarthritis and were treated with total knee arthroplasty. Minimum 1 mL knee synovial fluids were obtained during operation. Levels of U-II were measured by using ELISA kit U-II levels were significantly higher in the osteoarthritic group than that in the control group. No correlation was found between U-II levels and age. In conclusion, the significantly high U-II levels in the knee synovial fluid of osteoarthritic patients supported our hypothesis that “U-II may be associated with the synovial fibrosis in osteoarthritis”.

Behcet's disease (BD) is multisytemic vasculitis or chronic inflammation that may lead to various autoimmune and autoinflammatory syndromes. Exact etiopathogenesis of BD has not been clarified yet. Urotensin II (UTS-II) is predominantly a vasoactive peptide and Thr21Met polymorphism in UTS-II gene was proved to increasing in some autoimmune diseases. Considering these, our objective was to evaluate whether two UTS-II gene polymorphisms (Thr21Met and Ser89Asn) were responsible in genetic susceptibility to BD in a Turkish population. A total of 198 patients with BD and 275 healthy controls were enrolled. We analyzed the genotype and allele frequencies of two UTS-II gene polymorphisms, Thr21Met and Ser89Asn, in BD patients and in controls. We found that Thr21Met but not Ser89Asn polymorphisms of the UTS-II gene were markedly associated with the risk of developing BD (p0.0001), The Met21Met genotype was less common among BD patients (6.1% in patients vs. 17.1% in controls; p0.0001). There was also an increase in the 21Thr allele (54.8% in BD patients vs. 43.8% in controls) and a decrease in 21Met allele frequencies (45.2% in controls vs. 56.2% in patients) in the BD groups (p0.0044). To the best of our knowledge, for the first time in the literature, our study claims that there is an association between Thr21Met, and not between Ser89Asn polymorphisms in the UTS-II gene and BD. These results put a new player to the field of undiscovered pathogenesis of BD and hopefully provide new insights to the treatment options.

Objective.Systemic sclerosis (SSc) is an autoimmune chronic fibrotic disorder. Urotensin II (U-II) is predominantly a vasoactive peptide with fibrotic and prothrombotic features. Like endothelin-1 (ET-1), U-II could play an important role in SSc pathogenesis. We evaluated the possible role of the U-II gene polymorphisms (Thr21Met and Ser89Asn) in the genetic susceptibility to SSc in a Turkish population.Methods.A total of 189 patients with SSc and 205 healthy controls were enrolled in our study. We analyzed the genotype and allele frequencies of the U-II (UTS2) gene polymorphisms Thr21Met and Ser89Asn in patients with SSc and in controls.Results.We found that the Thr21Met polymorphism of the UTS2 gene was markedly associated with the risk of developing SSc (p < 0.0001), but there was no relationship between the Ser89Asn polymorphism and SSc (p > 0.05). Two haplotypes (MS and TS) were markedly associated with SSc (p < 0.05). There were significant associations between the genotype and allele frequencies of UTS2 gene Thr21Met polymorphism and cases with diffuse or limited SSc, systemic or lung involvement, finger flexion deformity, pitting scars at the fingertips, positive anticentromere, or positive antitopoisomerase 1 antibody groups.Conclusion.Our study shows the association between Thr21Met, but not Ser89Asn, in the UTS2 gene and SSc. The results strongly suggest that this single-nucleotide polymorphism may be an important risk factor in the development of SSc, and a powerful indicator of severe skin and lung involvement in patients with SSc.

This study describes the partitioning of 18 trace elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 9 major and minor elements (Al, Ca, Fe, K, Mg, Na, S, Si, Ti) during co-firing of olive residue, hazelnut shell and cotton residue with high sulfur and ash content lignite in 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig with limestone addition. Concentrations of trace elements in coal, biomass, limestone, bottom ash, cyclone ash and filter ash were determined by inductively coupled plasma optical emission and mass spectroscopy (ICP-OES and ICP-MS). Partitioning of major and minor elements are influenced by the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Tl, V and Zn) are recovered in fly ash when firing lignite only. Co-firing lignite with biomass enhances partitioning of these elements to fly ash. Co-firing also shifts the partitioning of Cd, P, Sb and Sn from bottom to fly ash. (C) 2008 Elsevier B.V. All rights reserved.

Combustion and emission behavior of 100 % steam coal (SET 1) and a mixture of 80 % by weight steam coal and 20 % by weight local lignite, characterized by high sulfur and ash contents, (SET 2) were investigated in the 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig. Experiments were performed with limestone addition at various Ca/S molar ratios with fines recycle. In both sets of experiments, parameters other than Ca/S molar ratio were held as nearly constant as possible. On-line measurements of O2 , CO2 , CO, SO2 , NOx emissions were carried out. Comparisons between the emissions show that lower NOx and SO2 emissions are obtained from combustion of steam coal/lignite mixture compared to those from steam coal only despite higher sulfur and almost equal nitrogen contents of the mixture. Calculated combustion efficiencies were found to be around 98 and 96 % for SET 1 and SET 2, respectively. As for the sulfur retention efficiencies, up to three times higher efficiencies were achieved when steam coal is co-fired with high sulfur lignite.Copyright © 2005 by ASME

Effect of recycle on radiative heat transfer in the freeboard of a fluidized bed combustor is investigated by applying a previously developed 3-D radiation model to the prediction of incident radiative heat fluxes along the freeboard walls of lignite-fired 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig and comparing its predictions with measurements. Freeboard is treated as a rectangular enclosure containing gray, absorbing, emitting and isotropically scattering medium bounded by gray and diffuse walls. Radiative properties of the medium are calculated by using Leckner’s correlations for gas and Mie theory for polydisperse particle cloud. Radiative transfer equation for this system is solved by using Method of Lines (MOL) solution of Discrete Ordinates Method (DOM). Experimental data required for application and validation are generated from two runs in which parameters other than recycle ratio was held as nearly constant as possible. Comparisons between predicted incident radiative heat fluxes and measurements with and without recycle reveal that the agreement is excellent and that the effect of recycle on incident radiative heat fluxes is significant. A parametric study is also carried out to investigate the effect of particle load on fluxes. Predictions are found to be relatively insensitive to the particle load but strongly affected by the temperature profile.Copyright © 2005 by ASME