4,539 research outputs found
Spillover impacts of sorghum research
A technological breakthrough in agriculture often leads to increased yields, or improves the quality
of output, or enhances the efficiency of input use. If the new technology has applicability beyond
the confines of the location for which it was generated, or beyond the commodity for which it was
developed, such an effect is commonly referred to as spillover effects. A review (Deb and Bantilan
2001) of the spillover impacts of agricultural research has covered the evolution of the concept
over time, different types of spillovers dealt in literature and techniques to quantify spillover
impacts by different studies on the subject..
Daily and monthly atmospheric variables and water salinity measurements at the Pichavaram mangrove and Kaziranga National Park in India
This dataset contains the daily averaged values of air temperature (Tair in deg C), air pressure (Pair in hPa), net radiation (Rn in W m-2), wind speed (WS in m s-1), vapour pressure deficit (VPD in hPa), transpiration (T in W m-2) and evaporation (E in W m-2), daily total rainfall (Pn in mm) at these two sites measured using micrometeorological tower-based sensors. It also contains the monthly averaged soil salinity (ST in ppt) measurement at the Pichavaram mangrove
Modeling restoration of gefitinib efficacy by co‐administration of MET inhibitors in an EGFR inhibitor‐resistant NSCLC xenograft model: A tumor‐in‐host DEB‐based approach
Abstract MET receptor tyrosine kinase inhibitors (TKIs) can restore sensitivity to gefitinib, a TKI targeting epidermal growth factor receptor (EGFR), and promote apoptosis in non‐small cell lung cancer (NSCLC) models resistant to gefitinib treatment in vitro and in vivo. Several novel MET inhibitors are currently under study in different phases of development. In this work, a novel tumor‐in‐host modeling approach, based on the Dynamic Energy Budget (DEB) theory, was proposed and successfully applied to the context of poly‐targeted combination therapies. The population DEB‐based tumor growth inhibition (TGI) model well‐described the effect of gefitinib and of two MET inhibitors, capmatinib and S49076, on both tumor growth and host body weight when administered alone or in combination in an NSCLC mice model involving the gefitinib‐resistant tumor line HCC827ER1. The introduction of a synergistic effect in the combination DEB‐TGI model allowed to capture gefitinib anticancer activity enhanced by the co‐administered MET inhibitor, providing also a quantitative evaluation of the synergistic drug interaction. The model‐based comparison of the two MET inhibitors highlighted that S49076 exhibited a greater anticancer effect as well as a greater ability in restoring sensitivity to gefitinib than the competitor capmatinib. In summary, the DEB‐based tumor‐in‐host framework proposed here can be applied to routine combination xenograft experiments, providing an assessment of drug interactions and contributing to rank investigated compounds and to select the optimal combinations, based on both tumor and host body weight dynamics. Thus, the combination tumor‐in‐host DEB‐TGI model can be considered a useful tool in the preclinical development and a significant advance toward better characterization of combination therapies
Presence of the Apolipoprotein E e4 allele is associated with the manifestation of Alzheimer dementia in adults with Down syndrome
Deb S, Braganza J, Norton N, Williams H, Kehoe PG, Williams J, Owen M
Comparative Study Between Ethylbenzene Disproportionation Reaction and its Ethylation Reaction with Ethanol over ZSM-5
Ethylation of ethylbenzene with ethanol has been studied over ZSM-5 catalyst in a riser simulator that mimics the operation of a fluidized-bed reactor. The feed molar ratio of ethylbenzene:ethanol is 1:1. The study was carried out at 350, 400, 450, and 500°C for reaction times of 3, 5, 7, 10, 13, and 15 s. Comparisons are made between the results of the ethylbenzene ethylation reaction with that of ethylbenzene disproportionation reaction earlier reported. The effect of reaction conditions on ethylbenzene reactivity, p-diethylbenzene selectivity, total diethylbenzene (DEB) isomers selectivity, p-DEB-to-m-DEB ratio, benzene-to-DEB molar ratio, and benzene selectivity, are reported. Benzene selectivity is about 10 times more in the EB disproportion reaction as compared to its ethylation reaction with ethanol at 350°C. In addition, the results showed a p-DEB/m-DEB ratio for the EB ethylation reaction varying between 1.2-1.7, which is greater than the equilibrium values. Increase in temperature shifts the alkylation/dealkylation equilibrium towards dealkylation, thereby decreasing conversion and selectivity to DEB. © Springer Science+Business Media, LLC 2009.The author would like to express his appreciation to King Abdullah University of Science and Technology (KAUST) for their financial support. Also, the support of the King Fahd University of Petroleum and Minerals is highly appreciated. Acknowledgement also goes to Mr. Mariano Gica for his help during the experimental work
Modelling growth and reproduction of the pacific oyster Crassostrea gigas: application of the oyster-DEB model in a coastal pond.
A bio-energetic model, based on the DEB theory exists for the Pacific oyster Crassostrea gigas. Pouvreau et al. [Pouvreau, S., Bourles, Y., Lefebvre, S., Gangnery, A., Alunno-Bruscia, M., 2006. Application of a dynamic energy budget model to the Pacific oyster, C. gigas, reared under various environmental conditions. J. Sea Res. 56, 156-167.] successfully applied this model to oysters reared in three environments with no tide and low turbidity, using chlorophyll a concentration as food quantifier. However, the robustness of the oyster-DEB model needs to be validated in varying environments where different food quantifiers reflect the food available for oysters, as is the case in estuaries and most coastal ecosystems. We therefore tested the oyster-DEB model on C. gigas reared in an Atlantic coastal pond from January 2006 to January 2007. The model relies on two forcing variables: seawater temperature and food density monitored through various food quantifiers. Based on the high temperature range measured in this oyster pond (3-30 °C), new boundary values of the temperature tolerance range were estimated both for ingestion and respiration rates. Several food quantifiers were then tested to select the most suitable for explaining the observed growth and reproduction of C. gigas reared in an oyster pond. These were: particulate organic matter and carbon, chlorophyll a concentration and phytoplankton enumeration (expressed in cell number per litre or in cumulative cell biovolume). We conclude that when phytoplankton enumeration was used as food quantifier, the new version of oyster-DEB model presented here reproduced the growth and reproduction of C. gigas very accurately. The next step will be to validate the model under contrasting coastal environmental conditions so as to confirm the accuracy of phytoplankton enumeration as a way of representing the available food that sustains oyster growth. © 2009 Elsevier B.V. All rights reserved
BACTERAEMIA WITH PLEURAL EFFUSIONS COMPLICATING TYPHOID FEVER CAUSED BY HIGH-LEVEL CIPROFLOXACIN-RESISTANT SALMONELLA ENTERICA SEROTYPE TYPHI
An unusual case of bacteraemia with bilateral pleural effusion caused by Salmonella enterica serotype Typhi in a 10-year-old previously healthy girl is reported. The organism was isolated from pleural fluid aspirate and from blood, and exhibited high-level ciprofloxacin resistance (MIC 16 μg/ml) associated with triple mutations in the QRDRs of the gyrA and parC genes leading to the amino-acid changes Ser83→Phe and Asp87→Asn in gyrA and Ser80→Ile in parC. The patient was successfully treated with parenteral ceftriaxone and intercostal chest tube drainage. The case is notable because of the important issue of antimicrobial resistance in S. Typhi and the therapeutic dilemma faced by clinicians regarding the empirical use of ciprofloxacin and newer fluoroquinolones
A novel method of forming micro- and macroporous monetite cements
Second to autologous bone grafts are the calcium phosphate cements (CPCs) used as synthetic bone substitutes due to their chemical similarity to the mineral component of bone. Their ability to conform to complex bone defects and excellent osteoconductivity also render them excellent scaffolds for bone tissue engineering, although they do have their own limitations. Calcium phosphates can be divided into two main categories, namely apatite and brushite. Apatites exhibit low solubility, whereas, calcium phosphates that set to form brushite, are metastable, which degrade rapidly, but do subsequently form hydroxyapatite that retards the rate. In contrast dicalcium phosphate anhydrous (monetite) has a higher solubility than octacalcium phosphate and does not transform to an apatite; thus, it is able to continue to degrade with time. Herein, a new method was used via the addition of sodium chloride to beta-tricalcium phosphate and monocalcium phosphate monohydrate to form micro- and macroporous monetite (DCPA). The X-ray diffraction and FTIR spectra confirmed the formation of monetite in the presence of both, 6.2 M NaCl solution or 60% of solid sodium chloride. The maximum compressive strength (sigma(c) = 12.3 +/- 1.8 MPa) and the Young's modulus (E = 1.0 +/- 0.1 GPa) of the monetite cements obtained were comparable to the upper limits of the values reported for cancellous bone and also higher than that reported by other routes used to form monetite. The porous cements analysed by microCT revealed an interconnected porosity with the preliminary in vitro biological evaluation indicating favourable osteoblast cell attachment and growth.</p
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