2,425 research outputs found
A comparison of soil moisture characteristics predicted by the Arya-Paris model with laboratory-measured data
Soil moisture characteristics predicted by the Arya-Paris model were compared with the laboratory measured data for 181 New Jersey soil horizons. For a number of soil horizons, the predicted and the measured moisture characteristic curves are almost coincident; for a large number of other horizons, despite some disparity, their shapes are strikingly similar. Uncertainties in the model input and laboratory measurement of the moisture characteristic are indicated, and recommendations for additional experimentation and testing are made
Evaluation of fungal and bacterial antagonists' seed treatment for controlling damping-off disease in forest nurseries
Biological control potential of six well reported biocontrol agents, Trichomerma viride, T. harzianum,
Gliocladium virens, Bacillus sp., B. subtilis and Pseudomonas fluorescens against Rhizoctonia solani,
R. bataticola, Fusarium oxysporum, F. moniliformae, F. solani and Phythium aphanidermatum causing damping-off in forest nurseries was studied in vitro and under screen house conditions. In vitro evaluation of biocontrol agents by dual inoculation method revealed that P. fluorescens, Bacillus sp. and T. viride significantly inhibited mycelial growth of the damping-offfungi. In pot experiments, seed treatment of T. viride and P. fluorescens proved superior to other fungal and bacterial biocontrol agents in reducing damping off (pre and post emergence) incidence compared to untreated controls
Accomplishments of the NASA Johnson Space Center portion of the soil moisture project in fiscal year 1981
The NASA/JSC ground scatterometer system was used in a row structure and row direction effects experiment to understand these effects on radar remote sensing of soil moisture. Also, a modification of the scatterometer system was begun and is continuing, to allow cross-polarization experiments to be conducted in fiscal years 1982 and 1983. Preprocessing of the 1978 agricultural soil moisture experiment (ASME) data was completed. Preparations for analysis of the ASME data is fiscal year 1982 were completed. A radar image simulation procedure developed by the University of Kansas is being improved. Profile soil moisture model outputs were compared quantitatively for the same soil and climate conditions. A new model was developed and tested to predict the soil moisture characteristic (water tension versus volumetric soil moisture content) from particle-size distribution and bulk density data. Relationships between surface-zone soil moisture, surface flux, and subsurface moisture conditions are being studied as well as the ways in which measured soil moisture (as obtained from remote sensing) can be used for agricultural applications
Entropy, Triangulation, and Point Location in Planar Subdivisions
A data structure is presented for point location in connected planar
subdivisions when the distribution of queries is known in advance. The data
structure has an expected query time that is within a constant factor of
optimal. More specifically, an algorithm is presented that preprocesses a
connected planar subdivision G of size n and a query distribution D to produce
a point location data structure for G. The expected number of point-line
comparisons performed by this data structure, when the queries are distributed
according to D, is H + O(H^{2/3}+1) where H=H(G,D) is a lower bound on the
expected number of point-line comparisons performed by any linear decision tree
for point location in G under the query distribution D. The preprocessing
algorithm runs in O(n log n) time and produces a data structure of size O(n).
These results are obtained by creating a Steiner triangulation of G that has
near-minimum entropy.Comment: 19 pages, 4 figures, lots of formula
NANODISCS: A NEW EPOCH IN THE STUDY OF MEMBRANE PROTEINS AND AS AN EMERGING DRUG DELIVERY SYSTEM
Nano discs recently evolved as a novel tool for studying the membrane associated proteins and serve as an effective drug delivery system. Nano discs constitute disc shaped nano particles and can be defined as a membrane system which is synthetic in nature and aids in the study of membrane proteins. It is mainly made of phospholipid bilayer and the water repelling edge is isolated by amphipathic proteins called membrane scaffolding proteins [MSP]. Micelles present in the nano disc mimics the property of the biological membrane proteins. It is a powerful technology that competently delivers the drug components in to the right cells in the right tissues. Membrane scaffold proteins are primarily expressed, purified and characterized and self-assembled to form Nano discs by the process of dialysis using biobeads. Nano discs are proven to be effective in the study of membrane proteins because they can fluidize and counterbalance and also help in reclusion, refinement, biophysical and biochemical studies of them. It also presents a more genuine environment than liposomes, bicelles, amphipols and detergent micelles. Major technological advantages of nano discs include the higher stability and carrier capacity and also the increased feasibility of incorporating both hydrophilic and hydrophobic substances of drug carrier. Thus nano discs serves as an excellent system in its ability to precisely control its composition and provide a nano scale membrane surface for investigating molecular recognition events. This article reviews the emphasis of nanodiscs in studying membrane proteins as well as its effectivity in transforming into a major drug delivery system. An overview of published literatures between 1996 and 2017 was conducted to write the review
3D-printed millimeter wave lens antenna
© 2017 IEEE. In this work, we present a flat lens design using the Dial-a-Dielectric (DaD) and 3D-printing technique to realize the materials that are not available off-the-shelf. We design the proposed flat lens and compare its performance with that of the ray-optics (RO)-based lens. We find from the results that both designs show comparable performance
Incremental Medians via Online Bidding
In the k-median problem we are given sets of facilities and customers, and
distances between them. For a given set F of facilities, the cost of serving a
customer u is the minimum distance between u and a facility in F. The goal is
to find a set F of k facilities that minimizes the sum, over all customers, of
their service costs.
Following Mettu and Plaxton, we study the incremental medians problem, where
k is not known in advance, and the algorithm produces a nested sequence of
facility sets where the kth set has size k. The algorithm is c-cost-competitive
if the cost of each set is at most c times the cost of the optimum set of size
k. We give improved incremental algorithms for the metric version: an
8-cost-competitive deterministic algorithm, a 2e ~ 5.44-cost-competitive
randomized algorithm, a (24+epsilon)-cost-competitive, poly-time deterministic
algorithm, and a (6e+epsilon ~ .31)-cost-competitive, poly-time randomized
algorithm.
The algorithm is s-size-competitive if the cost of the kth set is at most the
minimum cost of any set of size k, and has size at most s k. The optimal
size-competitive ratios for this problem are 4 (deterministic) and e
(randomized). We present the first poly-time O(log m)-size-approximation
algorithm for the offline problem and first poly-time O(log m)-size-competitive
algorithm for the incremental problem.
Our proofs reduce incremental medians to the following online bidding
problem: faced with an unknown threshold T, an algorithm submits "bids" until
it submits a bid that is at least the threshold. It pays the sum of all its
bids. We prove that folklore algorithms for online bidding are optimally
competitive.Comment: conference version appeared in LATIN 2006 as "Oblivious Medians via
Online Bidding
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