Pressure drop due to friction during internal pipe flow is one of the most important considerations in designing fluid and heat flow systems. There are many separate correlations valid for different ...situations such as laminar or turbulent rough and smooth surfaces for the estimation of friction factor. The present study introduces the derivation of a single explicit equation which is valid over the entire range of Reynolds number for both smooth and rough surfaces. This equation combines the laminar and turbulent friction factor equations through relation developed for the transition region. The results of the proposed equation were compared with the existing experimental data and the data from the Colebrook equation for smooth and rough surfaces respectively. The results show very good agreement with the experimental data as well as the Colebrook equation over the entire range of Reynold number. The percentage error lies within ±2% and ±10% for laminar and turbulent flows over the rough and smooth surfaces respectively.
Chest pain after thoracic trauma may be a symptom of cardiac injury or myocardial infarction. A 63-year-old healthy man had chest pain after blunt chest trauma in a motor vehicle accident. Chest ...computed tomography scan showed a displaced sternal fracture, lung contusion in the left upper lobe, atelectasis and consolidation in both lower lobes, and bilateral haemothorax. Electrocardiography showed ST elevation (2 mm) in leads II, III, and aVF and ST depression (2 mm) in leads I and aVL, consistent with acute inferior myocardial infarction. Urgent coronary angiography showed ostial occlusion of the right coronary artery. After the right coronary occlusion was passed with a guide wire, dissection of the right coronary artery was observed and treated with a balloon and stent to reestablish normal flow. This case emphasizes the importance of a high index of suspicion for coronary artery injury and myocardial infarction after blunt chest trauma.
•Fast production of ZnO nanorods was synthesized by bottom up approach using arc discharge in de-ionized water method.•A dye-sensitized solar cell based on ZnO nanorod displayed the most efficient ...solar to electricity conversion efficiency of the N719 dyes with a maximum η value of 6.96%.•We focused on the morphology, photocatalytical and optical properties of the ZnO nanorods.
Fast production of the ZnO nanorods by bottom up approach using arc discharge method in de-ionized water was carried out. Structural analysis showed that the obtained ZnO powder exhibits crystallize in the hexagonal wurtzite structure with (101) preferential orientation. Furthermore, transmission electron microscopy observations showed that rod-like structure is the abundant form with a bimodial grain size distribution around 10 and 30nm. Optical characterization of the as-synthesized ZnO nanorods revealed the existence of the two absorption and photoluminescence (PL) bands both located at UV spectral region attributed to the two grain size distributions. In addition, the two additional visible bands PL spectrum located at 430 and 492nm are attributed the interstitial zinc and oxygen vacancies; respectively. Dye sensitized solar cells (DSSCs) were successfully produced via different ruthenium based dyes and ferrocene liquid electrolyte by using of as synthesized ZnO nanorods modified photoanodes. It has been found that DSSCs made with N719 dye is the most efficient with photoconversion of approximately 7% compared to the other dyes. Such nanorod form of the ZnO nanostructures with ruthenium dyes resulted in significant improvements of the device performance in terms of electron transportation and UV light absorption. This work would explore feasible routes to synthesize efficient metal-oxide nanostructures for opto-electronic or other related applications.
Obsessive compulsive disorder (OCD) is a neurobiological disease characterized with obsessions and compulsions. Obsessive compulsive disorder occurs with an autoimmune mechanism after Group A β ...hemolytic streptococcus (GABHS) infection. Tumor necrosis factor (TNF) is an important cytokine, as well as having an important role in the apoptosis mechanism of autoimmune diseases. It is expressed by the TNF-α gene. The aim of this study was to examine the relationship between the TNF-α gene promoter region -308 (G>A) and -850 (C>T) polymorphisms and OCD. In this study, ages of the OCD patients and the control group ranged between 4 and 12 years. We studied two patient groups, one included childhood onset OCD patients (n = 49) and the control group was composed of healthy children (n = 58). Patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorder (DSM-IV) criteria and with Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime (KSAD-S-PL) version. For identifying the polyorphisms, polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and polyacrylamide gel electrophoresis (PAGE) methods were used. For the -308 polymorphism, 45 of 49 OCD patients’ results were completed, and for the -850 polymorphism, 47 of 49 OCD patients’ results were completed. According to our statistical results, there is a positive relationship between OCD and the -308 polymorphism (p <0.001) but no association between OCD and the -850 polymorphism (p = 0.053). There is no positive relationship between antistreptolysin O (ASO) titers and the -308 polymorphism (p = 0.953) but there is an important significance between the -850 polymorphism and ASO (p = 0.010). There is no positive relationship between gender of patients and OCD (p = 0.180) and no positive association between ASO and gender (p = 0.467). According to our results, we hypothesize that we can propose the mutant AA genotype for the -308 polymorphism, and that the mutant CT genotype for the -850 polymorphism may be used as molecular indicators for OCD.
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•We applied multi-locus species delimitation methods in the Eurasian blindsnake.•Four mtDNA species delimitation analyses identified 9 to 14 clusters.•Bayesian coalescence-based ...species delimitation identified two species.•We formally recognize two species and resurrect X. syriacus to include Levantine blindsnakes.•X. vermicularis and X. syriacus include cryptic diversity and may represent species-complexes.
Scolecophidia (worm snakes) are a vertebrate group with high ecomorphological conservatism due to their burrowing lifestyle. The Eurasian or Greek blindsnake Xerotyphlops vermicularis is their only European representative, a species-complex with an old diversification history. However, its systematics and taxonomy has remained untouched. Here, we extend previous work that relied heavily on mitochondrial markers, following a multi-locus approach and applying several species-delimitation methods, including a Bayesian coalescence-based approach (STACEY). Four “species” delimitation analyses based on the mtDNA (ABGD, bGMYC, mPTP, parsimony networks) returned 14, 11, 9 and 10 clusters, respectively. By mitotyping twice as many specimens as before, we have a complete picture of each cluster’s distribution. With the exception of the highly-divergent Levantine lineage, the three independent nuclear markers did not help with phylogenetic resolution, as demonstrated in haplotype networks, concatenated and species-trees, a result of incomplete lineage sorting. The prevailing model from the coalescence-based species-delimitation identified two species: the lineage from the Levant and all others. We formally recognize them as distinct species and resurrect Xerotyphlops syriacus (Jan, 1864) to include the Levantine blindsnakes. Finally, X. vermicularis and X. syriacus may represent species-complexes themselves, since they include high levels of cryptic diversity.
Neurological involvement is a well-documented issue in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). However, little is known about the involvement of the autonomic ...nervous system. This study was conducted to investigate autonomic nervous system dysfunction in patients with RA and SLE. Twenty-six RA patients, 38 SLE patients and 40 healthy controls were recruited from our in- and out-patient departments. Heart rate variability (HRV) parameters (the power of the high- HF and low-frequency LF band of haemodynamic time series, the ratio between low- and high-frequency components LF/HF ratio, the power spectral density), baroreflex sensitivity (BRS) and beat-to-beat blood pressures were assessed by a novel non-invasive haemodynamic monitoring tool (Task Force Monitor® TFM, CNSystems Medizintechnik GmbH, Graz, Austria). Autonomic nervous system dysfunction was determined according to classical Ewing autonomic test battery. Furthermore, we implemented a secondary autonomic test score by modifying the Ewing test battery with additional criteria. Both the classical and modified Ewing test batteries have revealed that the frequencies of autonomic neuropathy were significantly higher in patient groups compared with controls (p < 0.001). Evaluation by TFM revealed that deterioration of sophisticated autonomic parameters (such as HRV and BRS) were more pronounced in the patient groups compared with controls. There was a significant association between BRS and Ewing test scores and abnormal BRS results were more frequent in patients with autonomic dysfunction according to Ewing test batteries. No relation was found between autonomic neuropathy and disease duration, disease activity and autoantibody positivity. Consequently, we believe that further large-scale studies investigating cardiovascular autonomic neuropathy in rheumatic diseases should be carried out to verify our findings and manifest clinical consequences beyond these results. Lupus (2010) 19, 255—261.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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