70 research outputs found
Cloning, expression and characterization of L-arabinose isomerise from thermophilic Anoxybacillus kestanbolensis AC26Sari strain: Bioconversation of L-arabinose to L-ribulose
343-350L-Arabinose isomerase (L-AI) is a pivotal enzyme in the microbial pentose phosphate pathway. It is considered as a
significant biological catalyst in rare sugar production. This enzyme can isomerize L-arabinose into L-ribulose and also
D-galactose into D-tagatose. Here, we cloned the araA gene encoding L-arabinose isomerase from Anoxybacillus
kestanbolensis AC26Sari strain, sequenced and over-expressed in E. coli BL21 (DE3): pLysS. This gene is involved in
L-arabinose operon in A. kestanbolensis AC26Sari. DNA sequence analysis revealed an open reading frame of 1,506 bp,
capable of encoding a polypeptide of 502 amino acid residues with calculated molecular weight of 55.6776 kDa. The
recombinant was purified by heat treatment and Ni-HisTaq chromatography. The purified enzyme showed maximal activity
at pH 8.5 and 65ºC and required divalent cations such as Co2+ and Mn2+ for its activity and thermostability. The apparent Km
value of the enzyme for L-arabinose was 6.5 mM (Vmax, 140.1002 U/mg) as determined in the precence of both 1 mM Co2+
and Mn2+
The casualty chain inventory: a new scale for measuring peritraumatic responses: a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Peritraumatic psychological- and sensory impressions in victims of civilian accidents are only partly understood. This study scrutinizes the level and duration of perceived psychological threat at <it>scene of injury </it>as well as <it>in hospital </it>(the casualty chain) measured by the Casualty Chain Inventory (CCI). The purpose of the study was to assess and validate the CCI, and to examine the correlations between the new instrument and stress responses measured by the Impact of Event Scale (IES) and the Post-traumatic Stress Scale-10 (PTSS-10)</p> <p>Methods</p> <p>Three hundred and fifteen injured, conscious, hospitalised patients were assessed with a self-report questionnaire. The CCI consists of eight items including sensory impressions and well-known psychological responses to trauma.</p> <p>Results</p> <p>The internal consistency of the CCI was solid (Cronbach's alpha: .83-.85). A factor analysis revealed two components, "perception" and "dissociation". The instrument correlates significantly with the Impact of Event Scale (r = 0.47 - 0.54) and the Posttraumatic Stress Scale-10 (r = 0.32 - 0.50). The explained variance is high both at the scene of injury (61%) and in the hospital (65%). Dissociation and perception either used as a two-factor solution or as a sum score measured in the hospital, gave the strongest prediction for later psychological distress.</p> <p>Conclusions</p> <p>The CCI appears to be a useful screening instrument for, at an early state, identifying patients hospitalized after a physical incident at risk for subsequent psychological distress.</p
The links between health-related behaviors and life satisfaction in elderly individuals who prefer institutional living
BACKGROUND: Life satisfaction among residents of institutions is becoming an important issue in a rapidly aging population. The aim of this cross-sectional study was to investigate the links between life satisfaction and health-related behaviors amongst functionally independent elderly people who prefer institutional living in İstanbul, Turkey. METHODS: The socio-demographic characteristics, health-related behaviors, leisure-time activities and fall histories of 133 residents of an institution in Istanbul were assessed by a structured questionnaire during face-to-face interviews. A validated life-satisfaction index questionnaire (LSI-A) was completed. RESULTS: The mean age of the study group was 73.9 ± 8.0 (range 60–90 years). Within the group, 22.6% had never married and 14.3% had university degrees. The majority (71.4%) were in the low income bracket. The overall mean LSI-A score was 20.3 ± 5.9. Participants who declared moderate/high income levels had a significantly higher mean LSI-A score than those in the low-income bracket (p = 0.009). Multivariate analysis of the data suggested that leisure-time activities and participation in regular physical activities are significant predictors of LSI-A scores (R(2): 0.112; p = 0.005 and p = 0.02, respectively). CONCLUSION: The findings imply that regular physical activity and leisure-time activities are significantly related to life satisfaction among residents in institutions. Participation in physical activity and leisure-time activity programs may help to improve the life satisfaction of elderly people living in institutions
Dynamic Pricing and Learning: Historical Origins, Current Research, and New Directions
The frequency of shiga-like toxin (stx1 and stx2) and EHEC-hlyA in food by multiplex PCR
Aim: The aim of the present study was to determine the frequency of shiga-like toxin (stx1 and stx2) and drug resistance profiles food-borne Escherichia coli O157:H7 in Hatay province, Turkey. Methods: The presence of the virulence genes (stx1, stx2, hlyA) in a total of 150 E.coli isolates were studied with multiplex PCR. Results: A total of 327 salad samples were analyzed. E. coli O157:H7 was detected in 150 (45.8 %) out of 327 analyzed samples. Of these 150 isolates, the presence of hly-A gene was detected in 32 (21.3%) E.coli isolates. A total of five (15.6%) isolates in this 32 hlyA positive isolates had stx2 gene, two (6.3%) of them had stx1 gene and one (3.1%) of the isolates was found to be positive for both stx1 and stx2 genes. It was found that all E.coli O157:H7 isolates were resistant to erythromycin. While the highest rate of antibiotic resistance was observed for ampicillin (68.8%), no antibiotic resistance against cefuroxime, ciprofloxacin and cephaperasone was identified. Conclusions: The results obtained in our province showed that E.coli strains isolated from salad samples were found to have some important virulence genes such as stx1, stx2, and hlyA. The stx2 frequency was found to be higher than stx1 frequency. Also, it was observed that there was not any significant correlation between drug resistance profiles and presence of toxin genes in E.coli O157:H7 strains. As a result, increasing frequency of STEC O157 serotype among foodborne pathogens is a growing public health problem
Biodistribution and computed tomography studies on iopromide liposomes
Liposomes containing iopromide were prepared by film method followed by extrusion. Biodistribution and computed tomography imaging efficiency were evaluated in rats. Liposomes were taken up by the reticulo-endothelial system localized in the macrophages or Kupffer cells. The best biodistribution and computed tomography enhancement of the liver images were obtained with formulation E2 (PL100/SA/Chol 7/2/4 molar ratio, liquid crystalline state)
Cloning, expression and characterization of L-arabinose isomerisefrom thermophilic Anoxybacillus kestanbolensis AC26Sari strain:Bioconversation of L-arabinose to L-ribulose
L-Arabinose isomerase (L-AI) is a pivotal enzyme in the microbial pentose phosphate pathway. It is considered as asignificant biological catalyst in rare sugar production. This enzyme can isomerize L-arabinose into L-ribulose and alsoD-galactose into D-tagatose. Here, we cloned the araA gene encoding L-arabinose isomerase from Anoxybacilluskestanbolensis AC26Sari strain, sequenced and over-expressed in E. coli BL21 (DE3): pLysS. This gene is involved inL-arabinose operon in A. kestanbolensis AC26Sari. DNA sequence analysis revealed an open reading frame of 1,506 bp,capable of encoding a polypeptide of 502 amino acid residues with calculated molecular weight of 55.6776 kDa. Therecombinant was purified by heat treatment and Ni-HisTaq chromatography. The purified enzyme showed maximal activityat pH 8.5 and 65ºC and required divalent cations such as Co2+ and Mn2+ for its activity and thermostability. The apparent Kmvalue of the enzyme for L-arabinose was 6.5 mM (Vmax, 140.1002 U/mg) as determined in the precence of both 1 mM Co2+and Mn2+
CNN-LSTM and clustering-based spatial-temporal demand forecasting for on-demand ride services
Passenger demand forecasting is of great importance to the on-demand ride systems. With the accurate forecasting of demand, it can be determined from which regions and when the passengers demand a vehicle. In this way, passenger and vehicle waiting times, fuel costs of vehicles can be reduced. In the literature, various models such as time series, long short-term memory (LSTM), convolutional neural network (CNN), and hybrid of CNN-LSTM are used for demand forecasting in on-demand ride service systems. These models forecast demands by considering temporal and spatial data separately or together. In models that use spatial and spatial-temporal data, generally, the city is divided into zones in the form of a grid. This partitioning method has some disadvantages, such as misleading the forecasting accuracy by considering regions without demand and ignoring the geographical conditions. In this study, two new models, ConvLSTM2D-clustering and CNN-LSTM-clustering are proposed to overcome these disadvantages and make more accurate and robust forecasts. The proposed models use clustering instead of grid partitioning in dividing the city into zones and take time-of-day, time-of-week variables into account in forecasting as well as passenger demand. The presented models have been used in the passenger demand forecasting of Turkcell Technology Company, which provides on-demand ride services for its employees in Istanbul, Turkey. Experimental results, validated on real-world data provided by Turkcell, show that the proposed models partition the city more effectively and achieve 14-55% better short- and long-term forecasting performances than the compared models in terms of mean squared error.Algorithms and the Foundations of Software technolog
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