287 research outputs found
Junior high school EFL teachers’ attitudes towards collaborative action research
This study is aimed at analyzing high school EFL teachers’ attitudes towards collaborative action research (CAR
Developing a wet quality model using fuzzy approach for the Al-Gharraf River in Southern Iraq
The present study develops a wet quality model based on fuzzy approach to assessment of the surface wet quality in Al-Gharraf Stream located in the south of Iraq. The wet quality parameters, including Total Dissolved Solids (TDS), Biological Oxygen Demand (BOD), Chloride (CL), Sulphate (SO4), Nitrate (NO3), and Phosphate (PO4), were selected as input parameters to fuzzy wet quality model (FWQ. To evaluate the performance of the proposed model (FWQ) of Al-Gharraf Stream in the period of the study, the produces of our model were compared with those of the wet quality index (WQI) and Canadian Wet Quality Index (CWQI) . They showed similar results and were sensitive to changes in the level of wet quality parameters. However, the model proposed in the present study produced a more stringent produces compared to the WQI and CWQI. Results from the simulation indicate that the sensitivity analysis of the suggested approach will be improved by almost (17%, and 24%) more than that achieved by the processs WQIand CWQI respectively. In conclusion, the proposed index seems to produce accurate and reliable results and can be used as a comprehensive tool for wet quality assessment
DLX6-AS1: A long non-coding RNA with oncogenic features
Long non-coding RNAs (lncRNAs) are a heterogeneous group of ncRNAs with characteristic size of more than 200 nucleotides. An increasing number of lncRNAs have been found to be dysregulated in many human diseases particularly cancer. However, their role in carcinogenesis is not precisely understood. DLX6-AS1 is an lncRNAs which has been unveiled to be up-regulated in various number of cancers. In different cell studies, DLX6-AS1 has shown oncogenic role via promoting oncogenic phenotype of cancer cell lines. Increase in tumor cell proliferation, migration, invasion, and EMT while suppressing apoptosis in cancer cells are the effects of DLX6-AS1 in development and progression of cancer. In the majority of cell experiment, mediator miRNAs have been identified which are sponged and negatively regulated by DLX6-AS1, and they in turn regulate expression of a number of transcription factors, eventually affecting signaling pathways involved in carcinogenesis. These pathways form axes through which DLX6-AS1 promotes carcinogenicity of cancer cells. Xenograft animal studies, also have confirmed enhancing effect of DLX6-AS1 on tumor growth and metastasis. Clinical evaluations in cancerous patients have also shown increased expression of DLX6-AS1 in tumor tissues compared to healthy tissues. High DLX6-AS1 expression has shown positive association with advanced clinicopathological features in cancerous patients. Survival analyses have demonstrated correlation between high DLX6-AS1 expression and shorter survival. In cox regression analysis, DLX6-AS1 has been found as an independent prognostic factor for patients with various types of cancer
Bonding mechanism from the impact of thermally sprayed solid particles
Power particles are mainly in solid state prior to impact on substrates from high velocity oxy-fuel (HVOF) thermal spraying. The bonding between particles and substrates is critical to ensure the quality of coating. Finite element analysis (FEA) models are developed to simulate the impingement process of solid particle impact on substrates. This numerical study examines the bonding mechanism between particles and substrates and establishes the critical particle impact parameters for bonding. Considering the morphology of particles, the shear-instability–based method is applied to all the particles, and the energy-based method is employed only for spherical particles. The particles are given the properties of widely used WC-Co powder for HVOF thermally sprayed coatings. The numerical results confirm that in the HVOF process, the kinetic energy of the particle prior to impact plays the most dominant role in particle stress localization and melting of the interfacial contact region. The critical impact parameters, such as particle velocity and temperature, are shown to be affected by the shape of particles, while higher impact velocity is required for highly nonspherical powder
MIR-206 target prediction in breast cancer subtypes by bioinformatics tools
Background: MicroRNAs (miRNAs) are small endogenous non-coding RNAs with fundamental roles in the regulation of protein expression that is involved in the pathogenesis of many cancers including breast cancer. Among them is miR-206, whose role as a tumor suppressor gene has been demonstrated in breast cancer. Consequently, the identification of its putative target in breast cancer is of practical value. Methods: In the present study, we have suggested a new approach for the identification of miR-206 target genes with possible role in breast cancer pathogenesis. We used 15 online tools for the prediction of miR-206 target genes as well as gene expression data produced by DNA microarray technology. Results: By combining these two sets of data, we suggested a list of miR-206 target genes with possible involvement in breast cancer. In addition, we depicted an interaction network including miR-206 and its putative targets. Conclusions: Considering the complexity of miR-206 interactions with several targets, such in silico analyses would considerably lessen the work load of laboratory experiments. © 2018, Author(s)
Efficacy and safety of ipratropium bromide/albuterol compared with albuterol in patients with moderate-to-severe asthma: a randomized controlled trial
Abstract Background Many patients with asthma require frequent rescue medication for acute symptoms despite appropriate controller therapies. Thus, determining the most effective relief regimen is important in the management of more severe asthma. This study’s objective was to evaluate whether ipratropium bromide/albuterol metered-dose inhaler (CVT-MDI) provides more effective acute relief of bronchospasm in moderate-to-severe asthma than albuterol hydrofluoroalkaline (ALB-HFA) alone after 4 weeks. Methods In this double-blind, crossover study, patients who had been diagnosed with asthma for ≥1 year were randomized to two sequences of study medication “as needed” for symptom relief (1–7 day washout before second 4-week treatment period): CVT-MDI/ALB-HFA or ALB-HFA/CVT-MDI. On days 1 and 29 of each sequence, 6-hour serial spirometry was performed after administration of the study drug. Co-primary endpoints were FEV 1 area under the curve (AUC 0–6 ) and peak (post-dose) forced expiratory volume in 1 s (FEV 1 ) response (change from test day baseline) after 4 weeks. The effects of “as needed” treatment with ALB-HFA/CVT-MDI were analyzed using mixed effect model repeated measures (MMRM). Results A total of 226 patients, ≥18 years old, with inadequately controlled, moderate-to-severe asthma were randomized. The study met both co-primary endpoints demonstrating a statistically significant treatment benefit of CVT-MDI versus ALB-HFA. FEV 1 AUC 0-6h response was 167 ml for ALB-HFA, 252 ml for CVT-MDI (p <0.0001); peak FEV 1 response was 357 ml for ALB-HFA, 434 ml for CVT-MDI (p <0.0001). Adverse events were comparable across groups. Conclusions CVT-MDI significantly improved acute bronchodilation over ALB-HFA alone after 4 weeks of “as-needed” use for symptom relief, with a similar safety profile. This suggests additive bronchodilator effects of β 2 -agonist and anticholinergic treatment in moderate-to-severe, symptomatic asthma. Trial registration ClinicalTrials.gov No.: NCT00818454; Registered November 16, 2009
MicroRNA-135b promotes cancer progression by acting as a downstream effector of oncogenic pathways in colon cancer
MicroRNA deregulation is frequent in human colorectal cancers (CRCs), but little is known as to whether it represents a bystander event or actually drives tumor progression in vivo. We show that miR-135b overexpression is triggered in mice and humans by APC loss, PTEN/PI3K pathway deregulation, and SRC overexpression and promotes tumor transformation and progression. We show that miR-135b upregulation is common in sporadic and inflammatory bowel disease-associated human CRCs and correlates with tumor stage and poor clinical outcome. Inhibition of miR-135b in CRC mouse models reduces tumor growth by controlling genes involved in proliferation, invasion, and apoptosis. We identify miR-135b as a key downsteam effector of oncogenic pathways and a potential target for CRC treatment
The Multifunctional Host Defense Peptide SPLUNC1 Is Critical for Homeostasis of the Mammalian Upper Airway
Otitis media (OM) is a highly prevalent pediatric disease caused by normal flora of the nasopharynx that ascend the Eustachian tube and enter the middle ear. As OM is a disease of opportunity, it is critical to gain an increased understanding of immune system components that are operational in the upper airway and aid in prevention of this disease. SPLUNC1 is an antimicrobial host defense peptide that is hypothesized to contribute to the health of the airway both through bactericidal and non-bactericidal mechanisms. We used small interfering RNA (siRNA) technology to knock down expression of the chinchilla ortholog of human SPLUNC1 (cSPLUNC1) to begin to determine the role that this protein played in prevention of OM. We showed that knock down of cSPLUNC1 expression did not impact survival of nontypeable Haemophilus influenzae, a predominant causative agent of OM, in the chinchilla middle ear under the conditions tested. In contrast, expression of cSPLUNC1 was essential for maintenance of middle ear pressure and efficient mucociliary clearance, key defense mechanisms of the tubotympanum. Collectively, our data have provided the first in vivo evidence that cSPLUNC1 functions to maintain homeostasis of the upper airway and, thereby, is critical for protection of the middle ear
Change in genetic size of small-closed populations: Lessons from a domestic mammal population
The aim of this study was to monitor changes in genetic size of a small-closed population of Iranian Zandi sheep, by using pedigree information from animals born between 1991 and 2005. The genetic size was assessed by using measures based on the probability of identity-by-descend of genes (coancestry, f, and effective population size, Ne ), as well as measures based on probability of gene origin (effective number of founders, fe , effective number of founder genomes, fg , and effective number of non-founder genomes, fne ). Average coancestry, or the degree of genetic similarity of individuals, increased from 0.81% to 1.44% during the period 1993 to 2005, at the same time that Ne decreased from 263 to 93. The observed trend for fe was irregular throughout the experiment in a way that fe was 68, 87, 77, 92, and 80 in 1993, 1996, 1999, 2002, and 2005, respectively. Simultaneously, fg , the most informative effective number, decreased from 61 to 35. The index of genetic diversity (GD) which was obtained from estimates of fg , decreased about 2% throughout the period studied. In addition, a noticeable reduction was observed in the estimates of fne from 595 in 1993 to 61 in 2005. The higher than 1 ratio of fe to fg indicated the presence of bottlenecks and genetic drift in the development of this population of Zandi sheep. From 1993 to 1999, fne was much higher than fe , thereby indicating that with respect to loss of genetic diversity, the unequal contribution of founders was more important than the random genetic drift in non-founder generations. Subsequently, random genetic drift in non-founder generations was the major reason for fe > fne . The minimization of average coancestry in new reproductive individuals was recommended as a means of preserving the population against a further loss in genetic diversity
Ribbon Crystals
A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons using a ruled procedure where ribbons are uniquely described by two generating functions. This construction defines a differentiable frame, the ribbon frame, which does not have singular points, whereby we avoid the shortcomings of the Frenet-Serret frame. The observed spontaneous pattern is modeled using planar triangles and cylindrical arcs, and the ribbon structure is shown to arise from a maximization of the end-to-end length of the ribbon, i.e. from an optimal use of ribbon length. The phenomenon is discussed in the perspectives of incompatible intrinsic geometries and of the emergence of long-range order
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