10,622 research outputs found
Derivation of a dynamic model of the kinetics of nitrogen uptake throughout the growth of lettuce : calibration and validation
A kinetic model of nitrogen (N) uptake throughout growth was developed for lettuce
cultivated in nutrient solution under varying natural light conditions. The model couples
nitrogen uptake with dry matter accumulation using a two-compartment mechanistic
approach, incorporating structural and non-structural pools. Maximum nitrogen uptake
rates are assumed to decline with shoot dry weight, to allow for the effects of plant
age. The model was parameterized using data from the literature, and calibrated for
differences in light intensity using an optimization algorithm utilizing data from three
experiments in different growing seasons. The calibrated model was validated against
the data from two independent experiments conducted under different light conditions.
Results showed that the model made good predictions of nitrogen uptake by plants from
seedlings to maturity under fluctuating light levels in a glasshouse. Plants grown at a
higher light intensity showed larger maximum nitrogen uptake rates, but the effect of
light intensity declined towards plant maturity
A novel Artificial Neural Network-based streamline tracing strategy applied to hypersonic waverider design
Streamline tracing in conical hypersonic flows is essential for designing
high-performance waverider and intake. Conventionally, the streamline equations
are solved after obtaining the velocity field from the solution of the
axisymmetric conical flow field. The hypersonic waverider shape is generated
from the base conical flow field by repeatedly applying the streamline tracing
approach along several planes. When exploring the design space for optimization
of the waverider, streamline tracing can be computationally expensive. We
provide a novel strategy where first the Taylor-Maccoll equations for the
inviscid axisymmetric conical flowfield and the streamlines from the shock are
solved for a wide range of cone angle and Mach number conditions resulting in
an extensive database. The streamlines are parametrized by a third-order
polynomial, and an Artificial Neural Network (ANN) is trained to predict the
coefficients of the polynomial for arbitrary inputs of Mach number, cone angle,
and streamline originating location on the shock . We apply this strategy to
design a cone derived waverider and compare the geometry obtained with the
standard conical waverider design method and the simplified waverider design
method. The ANN technique is highly accurate, with a difference of 0.68% with
the standard in the coordinates of the waverider. RANS computations show that
the ANN derived waverider does not indicate severe flow spillage at the leading
edge, which is observed in the waverider generated from the simplified method.
The new ANN-based approach is 20 times faster than the conventional method
Surveillance of Pseudomonas in COPD patients in a tertiary care hospital
Background: Chronic pulmonary disease is increasing day by day due to lifestyle of general population. Smoking and air pollution are important factors. The present study was carried out to know the bacteriological profile of such cases.Methods: A total of 64 patients suffering with COPD were included in this study. Purulent sputum was collected from all the patients and subjected to routine bacteriological study. Culture positive were identified by routine bacteriological methods and antimicrobial susceptibility tests were performed using Kirby-Bauer disk diffusion method, MIC were determined following CLSI guidelines.Results: Out of 64 samples, 51 showed culture positive. Among aerobic bacteria, Pseudomonas was found to be predominant (54.05%) which was immediately followed by Klebsiella (45.94%). Amikacin was found to be effective (90%), followed by imipenim (85%) and trimethoprim (85%). The ureidopenicillin, piperacillin showed 70% sensitivity. All the strains were resistant to ampicillin and co-trimoxazole (100%). Conclusion: Antipseudomonal agents, imipenim and piperacillin were effective though slight resistance was noted. Therefore continuous monitoring of antipseudomonal agents is necessary to combat the development of resistance. Health education regarding smoking and air pollution needs to be strongly implemented.
Antibacterial and analgesic activity of leaves of Lantana camara
The leaves of the plant Lantana camara were extracted with different solvents and screened for their antibacterial and analgesic activities. The chloroform and methanolic extract of the plant Lantana camara has showed the presence of four alkaloid compounds each. Antibacterial activity was evaluated using MIC method against bacteria. The analgesic activity of different extracts of Lantana camara leaves is evaluated by Eddy’s hot plate method where the responses are jumping withdrawal of paws and licking of paws. This study demonstrates that leaf powder of Lantana camara has significant antibacterial and analgesic activities
Processing of Sorghum From Different Varieties and Hybrids for Semolina and Their Products
The present study was undertaken with the objective to standardise procedures for preparation of semolina (rava) from sorghum, to identify the best genotype for preparation of semolina and to study the nutritional quality parameters of semolina. For processing of sorghum, ten varieties and five hybrids were used for preparation of semolina and their products. A process has been standardized for semolina preparation using ultra grinding mill from sorghum grain. The semolina yield ranged from 46.51% to 54.29%. Hybrid CSH-15R gave the highest yield of semolina (54.29%). Starch content in semolina ranged from 59.93% to 66.43%. The new genotypes Phule Vasudha, Phule Yashoda and M 35-1 showed higher levels of starch content as compared to the other genotypes. The Phule Vasudha and Selection-3 showed higher levels of total soluble sugars in grains, as well as in semolina than the other genotypes. Phule Maulee gave higher level of crude fibre content (3.12%). The amino acid profile of sorghum grain and semolina showed very minor differences in the content due to the processing of sorghum grains into various products like semolina. The new genotypes of rabi sorghum showed comparable results for the mineral with that of hybrids. The organoleptic properties of the sweet (shira), upama and idali prepared from semolina were judged on the basis of colour, texture and appearance, flavour, taste and overall acceptability of the products using semi-trained judges and 1 to 9 hedonic scales. All products prepared from semolina were like very much and gave highest rating of more than 8 hedonic scales. While considering the yield of semolina from sorghum grains as well as their nutritional composition and organoleptic properties of the niche products (shira, upama, idali) prepared from them, the varieties Phule Vasudha and Phule Yashoda were the best one as compared to the other varieties and hybrids and overall varieties were better than the hybrids
EVALUATION OF ANTIOXIDANT AND CHEMOPREVENTIVE POTENTIAL OF METHANOLIC EXTRACTS OF LEAF OF AEGLEMARMELOS ATTRIBUTES TOWARDS DUCTAL CARCINOMA STUDIED IN MCF7 CELLS
Objective: The objective of the present research work had been made to evaluate the antioxidant potential along with anti-cancer activity of methanolic extracts from the leaf of A. marmelos.
Methods: Standard methods for antioxidant potential in terms of DPPH and nitric oxide scavenging assay, and anticancer activity in vitro method (Cytotoxicity/MTT assay and % of cell viability) by using MCF7 cell line.
Results: Results of antioxidant efficacy revealed that the IC50 value for DPPH and nitric oxide scavenging assay was considered to be 62.032%, and 20.69% respectively. The methanolic extract of A. marmelos was found to possess enhanced anticancer potential against MCF7 cells. Cytotoxicity activity of MCF7 cells, when treated with methanolic extract of A. marmelos, was found to be 43.42% at 25µg, 52.31% at 50µg, 56.31% at 75µg, 58.38% at 100µg, 62.25% at 125µg. The IC50 value was found as 49.36µg. Toxicity was significantly increased with increased concentration and viability significantly decreased with the increased concentration of methanolic extract of leaf from A. marmelos for MCF7 cell when compared to cyclophosphamide.
Conclusion: From the studies, it was postulated that methanolic extract of leaf from A. marmeloshas significant chemopreventive activity. These specific identities will be useful for the identification and authentication of raw drug
Dynamics of Magnetized Bulk Viscous Strings in Brans-Dicke Gravity
We explore locally rotationally symmetric Bianchi I universe in Brans-Dicke
gravity with self-interacting potential by using charged viscous cosmological
string fluid. We use a relationship between the shear and expansion scalars and
also take the power law for scalar field as well as self-interacting potential.
It is found that the resulting universe model maintains its anisotropic nature
at all times due to the proportionality relationship between expansion and
shear scalars. The physical implications of this model are discussed by using
different parameters and their graphs. We conclude that this model corresponds
to an accelerated expanding universe for particular values of the parameters.Comment: 17 pages, 6 figure
Mutation of Glycine 185 to Valine Alters the ATPase Function of the Human P-glycoprotein Expressed in Sf9 Cells
A single amino acid substitution, Gly185-->Val, in the human P-glycoprotein (Pgp) was previously shown to cause an altered pattern of drug resistance in cell lines transfected with the MDR1 cDNA carrying this mutation. To further define the function of amino acid 185 in the Pgp, the wild-type and the mutant Val185 Pgps were expressed in Sf9 insect cells, and their biochemical properties were compared. Verapamil- and colchicine-stimulated ATPase activities were markedly increased with concomitant increase in affinity for these compounds with Gly185-->Val substitution in the Pgp. However, the vinblastine-stimulated ATPase activities of the wild-type and Val185 Pgps were nearly identical. Because transport substrate-induced ATP hydrolysis is generally thought to reflect transport function, these data suggest that colchicine and verapamil are transported at an increased rate with Gly185-->Val substitution in the Pgp. These results also indicate that amino acid 185 is involved in verapamil and colchicine, but not in vinblastine, binding/transport. Kinetic analyses indicate that cyclosporin A, an inhibitor of Pgp, binds to the verapamil and vinblastine binding/transport site(s) in the Pgp. Taken together, the results presented herein reveal that the verapamil and vinblastine binding/transport site(s) are in close proximity and that the cyclosporin A binding site spans the common region of these two drug binding/transport site(s) in the Pgp molecule
PREVALENCE AND FACTORS ASSOCIATED WITH OBESITY AMONG ADULT AT THE KAMPUNG KOLAM, EAST COAST MALAYSIAN PENINSULA-A CROSS SECTIONAL STUDY
Objective: This study assesses the prevalence of obesity and its associated factors among adults aged 18 y and above at the Kampaung kolam, Kuala Terengganu, Malaysia.Methods: This cross-sectional survey comprised of a semi-structured face to face interview questionnaire and collected anthropometric measurements and sex specific waist circumference in cm. The study population was 70 in total with 21 (30%) males and 49 (70%) females aged 18 y and above were selected by universal sampling. Body mass index (BMI) was used for weight status and sex specific waist circumference (WC) in cm was used for assessment of abdominal or central obesity at risk of metabolic complications associated with obesity.Results: Among men, the prevalence of underweight was 9.5%, normal weight 57.1%, overweight 14.3% and obesity 19.1%, while among women, the prevalence of underweight was 12.2%, normal weight 53.1%, overweight 14.3% and obesity 20.4%. Overall, 18 (25.7%) was obese and 52 (74.3%) was non-obese while sex specific WC in cm 19 (27.1%) was abdominal obese who were at risk of metabolic complication associated with obesity and 51 (72.9%) was not at risk. In chi-square association tests revealed that among respondents, currently married, unemployed and having family history with obesity were associated with generalized obesity while respondents who were currently married and having fast food frequently were associated with abdominal obesity and respondents who being currently married, unemployed and having fast food frequently were more likely to obese in generalized as well as abdominally.Conclusion: There was no association between generalized, abdominal and generalized and abdominal obesity with age, gender, education, flat floor structure, dietary patterns and habits, physical activities, sleep pattern and knowledge and attitude level towards obesity but those factors can be utilized in effective health promotion programmers of weight management strategies by targeting those factors in design for prevention of hypertension, diabetes and related cardio vascular diseases CVD
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