291 research outputs found
Study of feeding habits of yellowfin tuna (Thunnus albacares) in the Oman Sea
Feeding habits of yellowfin tuna were studied in the Oman Sea in 1998-99. 546 stomach contents with fork length frequency 38-173 cm were studied and classified as full, semi full and empty. Occurence of empty Stomachs Were high (63.10 %) in males and 59.37%: in females) in the specimens which indicated daily feeding of yellowfin tuna. Purpleback flying squid (Sthenoteuthis oualaniensis) was the most dominant prey species observed in this study (60% in males and 57% in females), occurence of teleost fishes were found to be second (38% in mates and 42% in females). Furthermore, crabs were also identified as a part stomach contents with a low frequency (1-2%)
Quality of life among patients with beta-thalassemia major in Shahrekord city, Iran
Background and aims: Nowadays introduction of regular blood transfusion therapy has
obviously improved the life expectancy of patients with thalassemia. However, these
patients face with newer challenges which influence their quality of life (QoL). In this
study, the aim of this study was to measure QoL among patients with β-thalassemia
major (β-TM).
Methods: A cross-sectional study was done at the thalassemia centre of Shahrekord
University of Medical Sciences. All the forty patients with β-thalassemia which were
more than 12 years old referred to blood transfusion and participated in this study. Then,
they were asked to fill out the Short Form Health Status Survey (SF-36) questionnaire.
The questionnaire evaluates 8 health areas including physical functioning (PF), rolephysical
(RP), bodily pain (BP), general health (GH), vitality (VT), social functioning
(SF), role-emotional (RE) and mental health (MH). The scores of each participant were
calculated and data were analyzed using SPSS.
Results: There were 18 men and 22 women, and the mean age was 21.69±5.74 years
(range 12-38). No significant difference was seen in QoL between men and women
(68.72±19.79 versus 67.47±18.80, P=0.84). The mean±SD score of PF, RP, BP, GH, VT,
SF, MH was 80.5±16, 83.75±29.17, 71.94±24.22, 57.48±23.93, 54.36±22.51,
68.94±23.37, 66.33±36.04 and 58.51±23.68, respectivly. No significant differences were
detected in all mentioned scores between men and women (P>0.05).
Conclusion: Although most of the participants had suitable physical functioning,
thalassemia had a negative effect on emotional role, social functioning and mental health
of patients. It shows the importance of psychosocial supports for these patients
Sex ratio and length determination at the onset of maturity of rock oyster Saccostrea cucullata in the Oman Sea
Sex ratio and length at maturity in the rock oyster, Saccostrea cucullata was studied in the Iranian shores of Oman Sea. Monthly sampling was conducted 10 stations within one year period (March 1996 to February 1997). Results indicated that sex ratio is 1:1. Among the first matured age groups, nearly 67 percent of the samples were male and 33 percent were female. With increasing size, the percentage of females were increased, indicating a protandric nature. More than 50 percent of the samples were matured when their length exceeded 36 mm. Smallest matured specimen had a length of 22 mm
Determinants of Student Absenteeism/Presenteeism in Qatar: A Path Analysis
The current study sought to investigate the perceptions of school teachers regarding student absenteeism and presenteeism in the State of Qatar. Drawing on the existing relevant literature in the field and based on a survey research method, the study was carried out during the first term (Fall semester) in 2015. The study involved preparatory (middle) and secondary (high) school teachers at both public (Independent) and private (International) schools in Qatar. To attain this goal, a causal model was used to examine the causes that shape teachers’ perceptions of absenteeism and presenteeism. The data required for the present research was collected from a sample of 495 teachers at Independent and International schools. Based on factor analysis, the findings concluded from the study indicated that seven valid dimensions were extracted. In addition, three determinant factors that influence the perceptions of preparatory and secondary school teachers with regard to students’ absentee and presentee behaviours were identified. These factors are: (a) reviewing curriculum content, (b) the teaching load, and (c) the expected rate of student graduations. The study concludes by offering some important recommendations for education practitioners and policy makers as well as some useful suggestions for future research and practice
The effect of resveratrol on the expression of MDR1 gene in leukemic lymphoblast's of acute lymphoblastic leukemia patients
Background: Chemotherapy plays a very important role in the treatment of leukemia but the resistance properties of the lymphoblasts limit the effect of chemotherapy. One of the main mechanisms of resistance to chemotherapy is the increased expression of MDR1 gene. The aim of this study was to explore the effect of resveratrol on the expression of MDR1 gene in leukemic lymphoblast of new cases of acute lymphoblastic leukemia (ALL) patients in vitro. Methods: Separation of lymphoblasts of 5 new case ALL patients from peripheral blood was performed by ficoll density gradient centrifugation. Lymphoblasts were cultured in RPMI 1640 medium. Lymphoblasts were treated with 50μmol/L resveratrol for 48 h. Total RNA was extracted with guanidine isothiocyanate. RNA was converted to cDNA. Real time PCR was used to detect mRNA expression of MDR1. Results: The results of gene detection showed that the expression of MDR1 did not change significantly in the patients however, in one patient expression of MDR1 increased upon treatment with resveratrol. Conclusion: The results of this study did not support resveratrol as a compound to reverse multidrug resistance in leukemic lymphoblasts
Game-Based Cryptanalysis of a Lightweight CRC-Based Authentication Protocol for EPC Tags
The term Internet of Things (IoT) expresses a huge network of smart and connected objects which can interact with other devices without our interposition. Radio frequency identification (RFID) is a great technology and an interesting candidate to provide communications for IoT networks, but numerous security and privacy issues need to be considered. In this paper, we analyze the security and the privacy of a new RFID authentication protocol proposed by Shi et al. in 2014. We prove that although Shi et al. have tried to present a secure and untraceable authentication protocol, their protocol still suffers from several security and privacy weaknesses which make it vulnerable to various security and privacy attacks. We present our privacy analysis based on a well-known formal privacy model which is presented by Ouafi and Phan in 2008. Moreover, to stop such attacks on the protocol and increase the performance of Shi et al.’s scheme, we present some modifications and propound an improved version of the protocol. Finally, the security and the privacy of the proposed protocol were analyzed against various attacks
Predicting Stress-Strain Behavior of Normal Weight and Lightweight Aggregate Concrete Exposed to High Temperature Using LSTM Recurrent Neural Network
Foliar nutrient resorption patterns of four functional plants along a precipitation gradient on the Tibetan Changtang Plateau
Nutrient resorption from senesced leaves as a nutrient conservation strategy
is important for plants to adapt to nutrient deficiency, particularly in
alpine and arid environment. However, the leaf nutrient resorption patterns of
different functional plants across environmental gradient remain unclear. In
this study, we conducted a transect survey of 12 communities to address foliar
nitrogen (N) and phosphorus (P) resorption strategies of four functional
groups along an eastward increasing precipitation gradient in northern Tibetan
Changtang Plateau. Soil nutrient availability, leaf nutrient concentration,
and N:P ratio in green leaves ([N:P]g) were linearly correlated with
precipitation. Nitrogen resorption efficiency decreased, whereas phosphorus
resorption efficiency except for sedge increased with increasing
precipitation, indicating a greater nutrient conservation in nutrient-poor
environment. The surveyed alpine plants except for legume had obviously higher
N and P resorption efficiencies than the world mean levels. Legumes had higher
N concentrations in green and senesced leaves, but lowest resorption
efficiency than nonlegumes. Sedge species had much lower P concentration in
senesced leaves but highest P resorption efficiency, suggesting highly
competitive P conservation. Leaf nutrient resorption efficiencies of N and P
were largely controlled by soil and plant nutrient, and indirectly regulated
by precipitation. Nutrient resorption efficiencies were more determined by
soil nutrient availability, while resorption proficiencies were more
controlled by leaf nutrient and N:P of green leaves. Overall, our results
suggest strong internal nutrient cycling through foliar nutrient resorption in
the alpine nutrient-poor ecosystems on the Plateau. The patterns of soil
nutrient availability and resorption also imply a transit from more N
limitation in the west to a more P limitation in the east Changtang. Our
findings offer insights into understanding nutrient conservation strategy in
the precipitation and its derived soil nutrient availability gradient
Prevalence, and virulence determination of listeria monocytogenes strains isolated from clinical and non-clinical samples by multiplex polymerase chain reaction
Introduction: This study aimed to determine the prevalence, and virulence factors of Listeria monocytogenes isolated from various samples by multiplex polymerase chain reaction (MPCR). Methods: A total of 617 isolates were obtained and MPCR was employed for detection of the inlA, inlC, and inlJ genes. Results: L. monocytogenes was detected in 46 (7.45) of the 617 specimens. inlA, inlC, and inlJ were detected in 100, 76.26, and 71 isolates, respectively. Conclusions: This study validated MPCR in the analysis and rapid detection of L. monocytogenes. The role of the genes in pathogenesis of the strains can also be affirmed. © 2016, Sociedade Brasileira de Medicina Tropical. All rights reserved
Relationship between casting modulus and grain size in cast A356 aluminium alloys
Microstructure of Al-Si alloy castings depends most generally on melt preparation and on the cooling rate imposed by the thermal modulus of the component. In the case of Al-Si alloys, emphasis is put during melt preparation on refinement of pro-eutectic (Al) grains and on modification of the Al-Si eutectic. Thermal analysis has been used since long to check melt preparation before casting, i.e. by analysis of the cooling curve during solidification of a sample cast in an instrumented cup. The conclusions drawn from such analysis are however valid for the particular cooling conditions of the cups. It thus appeared of interest to investigate how these conclusions could extrapolate to predict microstructure in complicated cast parts showing local changes in the solidification conditions. For that purpose, thermal analysis cups and instrumented sand and die castings with different thermal moduli and thus cooling rates have been made, and the whole set of cooling curves thus recorded has been analysed. A statistical analysis of the characteristic features of the cooling curves related to grain refinement in sand and die castings allowed determining the most significant parameters and expressing the cube of grain size as a polynomial of these parameters. After introduction of a further parameter quantifying melt refining an excellent correlation, with a R2 factor of 0.99 was obtained
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