2,620 research outputs found
Association of diverse bacterial communities in human bile samples with biliary tract disorders: a survey using culture and polymerase chain reaction-denaturing gradient gel electrophoresis methods
Bacterial infection is considered a predisposing factor for disorders of the biliary tract. This study aimed to determine the diversity of bacterial communities in bile samples and their involvement in the occurrence of biliary tract diseases. A total of 102 bile samples were collected during endoscopic retrograde cholangiopancreatography (ERCP). Characterization of bacteria was done using culture and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) methods. Antimicrobial susceptibility of the isolates was determined based on the Clinical and Laboratory Standards Institute (CLSI) guidelines and identity of the nucleotide sequences of differentiated bands from the DGGE gels was determined based on GenBank data. In total, 41.2 (42/102) of the patients showed bacterial infection in their bile samples. This infection was detected in 21 (4/19), 45.4 (5/11), 53.5 (15/28), and 54.5 (24/44) of patients with common bile duct stone, microlithiasis, malignancy, and gallbladder stone, respectively. Escherichia coli showed a significant association with gallstones. Polymicrobial infection was detected in 48 of the patients. While results of the culture method established coexistence of biofilm-forming bacteria (Pseudomonas aeruginosa, E. coli, Klebsiella pneumoniae, Enterococcus spp., and Acinetobacter spp.) in different combinations, the presence of Capnocytophaga spp., Lactococcus spp., Bacillus spp., Staphylococcus haemolyticus, Enterobacter or Citrobacter spp., Morganella spp., Salmonella spp., and Helicobacter pylori was also characterized in these samples by the PCR-DGGE method. Multidrug resistance phenotypes (87.5 ) and resistance to third- and fourth-generation cephalosporins and quinolones were common in these strains, which could evolve through their selection by bile components. Ability for biofilm formation seems to be a need for polymicrobial infection in this organ. © 2016 Springer-Verlag Berlin Heidelber
Coupled Two-Way Clustering Analysis of Gene Microarray Data
We present a novel coupled two-way clustering approach to gene microarray
data analysis. The main idea is to identify subsets of the genes and samples,
such that when one of these is used to cluster the other, stable and
significant partitions emerge. The search for such subsets is a computationally
complex task: we present an algorithm, based on iterative clustering, which
performs such a search. This analysis is especially suitable for gene
microarray data, where the contributions of a variety of biological mechanisms
to the gene expression levels are entangled in a large body of experimental
data. The method was applied to two gene microarray data sets, on colon cancer
and leukemia. By identifying relevant subsets of the data and focusing on them
we were able to discover partitions and correlations that were masked and
hidden when the full dataset was used in the analysis. Some of these partitions
have clear biological interpretation; others can serve to identify possible
directions for future research
Multi-criteria decision making (MCDM) model for seismic vulnerability assessment (SVA) of urban residential buildings
© 2018 by the authors. Earthquakes are among the most catastrophic natural geo-hazards worldwide and endanger numerous lives annually. Therefore, it is vital to evaluate seismic vulnerability beforehand to decrease future fatalities. The aim of this research is to assess the seismic vulnerability of residential houses in an urban region on the basis of the Multi-Criteria Decision Making (MCDM) model, including the analytic hierarchy process (AHP) and geographical information system (GIS). Tabriz city located adjacent to the North Tabriz Fault (NTF) in North-West Iran was selected as a case study. The NTF is one of the major seismogenic faults in the north-western part of Iran. First, several parameters such as distance to fault, percent of slope, and geology layers were used to develop a geotechnical map. In addition, the structural construction materials, building materials, size of building blocks, quality of buildings and buildings-floors were used as key factors impacting on the building’s structural vulnerability in residential areas. Subsequently, the AHP technique was adopted to measure the priority ranking, criteria weight (layers), and alternatives (classes) of every criterion through pair-wise comparison at all levels. Lastly, the layers of geotechnical and spatial structures were superimposed to design the seismic vulnerability map of buildings in the residential area of Tabriz city. The results showed that South and Southeast areas of Tabriz city exhibit low to moderate vulnerability, while some regions of the north-eastern area are under severe vulnerability conditions. In conclusion, the suggested approach offers a practical and effective evaluation of Seismic Vulnerability Assessment (SVA) and provides valuable information that could assist urban planners during mitigation and preparatory phases of less examined areas in many other regions around the world
An Investigation of the Effect of Ventilation Inlet and Outlet Arrangement on Heat Concentration in a Ship Engine Room
Τhe ventilation in the ship engine rooms is an essential issue concerning finest performance of engines and diesel generators as well as electric motors. The present study has aimed at the analysis of temperature distribution inside the ship main engine room. In the same way, attempts have been made to identify those points with considerable thermal concentration in main engine room space, so that proper ventilation systems could be engineered and utilized and favorable thermal conditions could be realized. The CFD approach has been utilized in order to analyze impact of the designed ventilation system on the temperature distribution pattern. The Inlet layout and area have been analyzed under a variety of scenarios in order to decrease the average temperature and eliminate the heat concentrations in various points of the engine room. The temperature distribution and location and area of ventilation air inlet have been studied in different modes resulted in temperature distribution pattern, heat concentration outline and average volumetric temperature level in each mode. The results indicated that considerable circulating air volume is required compared to those levels suggested by common practices, calculations and standards in order to eliminate the heat concentration
A CFD Study of Industrial Double-Cyclone in HDPE Drying Process
Double-cyclone in fluidized bed drying is an important equipment which reflects the conditions of drying in HDPE slurry process. Cyclone is an important unite of fluidized bed drying in order to move the solid particles outward to its wall. Therefore, flow pattern created in fluidized bed will affect industrial cyclones installed in dryer for dust removing. Pressure drop of the cyclones is an effective parameter represents the drying behavior. Substantially, geometry of cyclone, inlet flow rate of gas, density and particle size distribution (PSD) can affect the pressure drop value. Fluidized bed hydrodynamic regime is very complex and must be understood to improve fluidized bed operations through theoretical, industrial and CFD study of double-cyclone. Pressure drop is introduced as parameter related to the cyclone efficiency can be calculated with ANSYS Fluent software in the Eulerian-Lagrangian framework with RNG k-ɛ turbulence model used as a mathematical method. Proper pressure drop concluded from industrial experiments and CFD calculation shows good fluidization of HDPE particles in the bed of nitrogen and powder to reach the best fluidized bed situation and suitable quality of HDPE powdery product
Intralobular pulmonary sequestration
Background: A 59-year-old non-smoking woman, with a history of gall stones, type 2 diabetes mellitus and hypertension, was referred to our hospital because of persistent coughing, night sweats, headaches and weight loss. Clinical examination revealed no abnormalities. The laboratory findings on admission were as follows: erythrocyte sedimentation rate was 39 mm/h, C-reactive protein level was 62 mg/mL and leukocyte count was 8.0 x 109/L. Bronchoscopic examination showed a normal bronchial tree
Use of poultry pre-cooked slaughterhouse waste as ruminant feed to prevent environmental pollution
The generation of poultry slaughterhouse waste from poultry production is not only unavoidable but the amount and kinds of waste can cause environmental problems. In the present study, the potential rumen digestion of poultry slaughterhouse waste which consists of protein-rich organic residues was evaluated. The chemical composition, amino acid profile and Cornell Net Carbohydrate and Protein System fractions of these wastes was determined. Rumen digestion of poultry slaughterhouse waste was compared with two common protein sources (fish meal and roasted soybean). Three poultry slaughterhouse waste samples were collected from industrial poultry slaughter-houses and the in situ degradation was done using rumen cannulated sheep. The protein (50e63%), ether extracts (18e27%) and ash (9e15.5%) contents of different poultry slaughterhouse waste samples were different (P < 0.05). Methionine and lysine contents were similar among different poultry slaughterhouse waste sources. Difference were observed for cystine (1.2e1.7%), threonine (1.9e2.2%), arginine (3e3.5%), leucine (3.5e4.1%) and valine (2.8e3.3%) (P < 0.05). Ruminal degradation rate for dry matter, organic matter and protein were different among poultry slaughterhouse waste, fish meal and roasted soybean. The degradation parameter for protein degradation was 76% for poultry slaughterhouse waste, 79% for fish meal and 98% for roasted soybean (P < 0.05). Results revealed that there was great variation in chemical composition, protein fractioning, and amino acid profiles of different poultry slaughterhouse waste sources. Poultry slaughterhouse waste is slowly-degraded protein in the rumen and thus can be an economical and rich source of rumen undegradable protein in ruminant nutrition. This implies that the use of poultry slaughterhouse waste in ruminant nutrition has a huge potential as a cleaner product of animal feeding and prevention environmental pollution. However, further studies are warranted to evaluate the digestibility of poultry slaughterhouse waste amino acids escaping the rumen into the intestine in ruminants and to compare the biological values for the amino acids in these waste material with common ruminant feedstuffs
- …