146 research outputs found
Effect of super-optimal levels of fertilizers on soil enzymatic activities during growth stages of wheat crop on an Inceptisol
A field experiment was conducted during 2010-2011 and 2011-2012 to investigate the effect of optimal (100% NPK) to super-optimal doses (200% NPK) of mineral fertilizers on soil enzymes such as dehydrogenase (DHA), acid phosphatase (Ac-PA), alkaline phosphatase (Alk-PA), fluorescien diacetate hydrolysis (FDA), urease and nitrate reductase (NRA) at three physiological stages (CRI, anthesis and maturity) of wheat crop on an Inceptisol. Dehydrogenase activity was reduced by 28-37% when fertilizer application was at super-optimal dose (200% NPK), whereas, urease and NRA responded positively in the range of 43-44% and 213-231% respectively. Alk-PAwas 7.3-7.9% higher in treatments receiving 125% NPK as compared to control (100% NPK); whereas, Ac-PA declines in the plots receiving 175 and 200% of recommended dose of fertilizer (RDF) as compared to 150% NPK levels. Addition of 175% RDF increased the FDA to the tune of 46-53% as compared to 100% NPK. A significant (P?0.05) positive interaction between fertilizer treatments and physiological stages of wheat growth was observed on soil enzyme activities (except urease and NRA) being highest at the anthesis stage of wheat. Correlation matrix analysis showed that DHA was correlated with the studied enzyme activities except Ac-PA and FDA; whereas, strong correlation was observed between urease and NRA (r=0.981, P=0.01). This study provides theoretical and practical base for avoiding super optimal application of fertilisers which hinders the enzyme activities and vis-a-vis sustainable nutrient enrichment under rhizosphere
Magnetocrystalline anisotropy in RAu_{2}Ge_{2} (R = La, Ce and Pr) single crystals
Anisotropic magnetic properties of single crystalline RAu_{2}Ge_{2} (R = La,
Ce and Pr) compounds are reported. LaAu_{2}Ge_{2} exhibit a Pauli-paramagnetic
behavior whereas CeAu_{2}Ge_{2} and PrAu_{2}Ge_{2} show an antiferromagnetic
ordering with N\grave{e}el temperatures T_{N} = 13.5 and 9 K, respectively. The
anisotropic magnetic response of Ce and Pr compounds establishes [001] as the
easy axis of magnetization and a sharp spin-flip type metamagnetic transition
is observed in the magnetic isotherms. The resistance and magnetoresistance
behavior of these compounds, in particular LaAu_{2}Ge_{2}, indicate an
anisotropic Fermi surface. The magnetoresistivity of CeAu_{2}Ge_{2} apparently
reveals the presence of a residual Kondo interaction. A crystal electric field
analysis of the anisotropic susceptibility in conjunction with the
experimentally inferred Schottky heat capacity enables us to propose a crystal
electric field level scheme for Ce and Pr compounds. For CeAu_{2}Ge_{2} our
values are in excellent agreement with the previous reports on neutron
diffraction. The heat capacity data in LaAu_{2}Ge_{2} show clearly the
existence of Einstein contribution to the heat capacity.Comment: Submitted to PRB 11 Pages 13 Figure
ANN-based energy reconstruction procedure for TACTIC gamma-ray telescope and its comparison with other conventional methods
The energy estimation procedures employed by different groups, for
determining the energy of the primary -ray using a single atmospheric
Cherenkov imaging telescope, include methods like polynomial fitting in SIZE
and DISTANCE, general least square fitting and look-up table based
interpolation. A novel energy reconstruction procedure, based on the
utilization of Artificial Neural Network (ANN), has been developed for the
TACTIC atmospheric Cherenkov imaging telescope. The procedure uses a 3:30:1 ANN
configuration with resilient backpropagation algorithm to estimate the energy
of a -ray like event on the basis of its image SIZE, DISTANCE and
zenith angle. The new ANN-based energy reconstruction method, apart from
yielding an energy resolution of 26%, which is comparable to that of
other single imaging telescopes, has the added advantage that it considers
zenith angle dependence as well. Details of the ANN-based energy estimation
procedure along with its comparative performance with other conventional energy
reconstruction methods are presented in the paper and the results indicate that
amongst all the methods considered in this work, ANN method yields the best
results. The performance of the ANN-based energy reconstruction has also been
validated by determining the energy spectrum of the Crab Nebula in the energy
range 1-16 TeV, as measured by the TACTIC telescope.Comment: 23pages, 9 figures Accepted for publication in NIM
Observations of TeV gamma-rays from Mrk 421 during Dec. 2005 to Apr. 2006 with the TACTIC telescope
The TACTIC -ray telescope has observed Mrk 421 on 66 clear nights
from Dec. 07, 2005 to Apr. 30, 2006, totalling 202 hours of on-source
observations. Here, we report the detection of flaring activity from the source
at 1 TeV energy and the time-averaged differential -ray spectrum
in the energy range 1-11 TeV for the data taken between Dec. 27, 2005 to Feb.
07, 2006 when the source was in a relatively higher state as compared to the
rest of the observation period. Analysis of this data spell, comprising about
97h reveals the presence of a -ray signal with
daily flux of 1 Crab unit on several days. A pure power law spectrum with
exponent as well as a power law spectrum with an exponential
cutoff and are found to provide
reasonable fits to the inferred differential spectrum within statistical
uncertainties. We believe that the TeV light curve presented here, for nearly 5
months of extensive coverage, as well as the spectral information at
-ray energies of 5 TeV provide a useful input for other groups
working in the field of -ray astronomy.Comment: 13pages,4figures; Accepted for publication in Astroparticle Physic
The three-dimensional random field Ising magnet: interfaces, scaling, and the nature of states
The nature of the zero temperature ordering transition in the 3D Gaussian
random field Ising magnet is studied numerically, aided by scaling analyses. In
the ferromagnetic phase the scaling of the roughness of the domain walls,
, is consistent with the theoretical prediction .
As the randomness is increased through the transition, the probability
distribution of the interfacial tension of domain walls scales as for a single
second order transition. At the critical point, the fractal dimensions of
domain walls and the fractal dimension of the outer surface of spin clusters
are investigated: there are at least two distinct physically important fractal
dimensions. These dimensions are argued to be related to combinations of the
energy scaling exponent, , which determines the violation of
hyperscaling, the correlation length exponent , and the magnetization
exponent . The value is derived from the
magnetization: this estimate is supported by the study of the spin cluster size
distribution at criticality. The variation of configurations in the interior of
a sample with boundary conditions is consistent with the hypothesis that there
is a single transition separating the disordered phase with one ground state
from the ordered phase with two ground states. The array of results are shown
to be consistent with a scaling picture and a geometric description of the
influence of boundary conditions on the spins. The details of the algorithm
used and its implementation are also described.Comment: 32 pp., 2 columns, 32 figure
Chip-Firing and Rotor-Routing on Directed Graphs
We give a rigorous and self-contained survey of the abelian sandpile model
and rotor-router model on finite directed graphs, highlighting the connections
between them. We present several intriguing open problems.Comment: 34 pages, 11 figures. v2 has additional references, v3 corrects
figure 9, v4 corrects several typo
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Effect of Capillarity on Fourth Order Nonlinear Evolution Equation for Two Stokes Wave Trains in Deep Water in the Presence of Air Flowing Over Water
Fourth order nonlinear evolution equations, which are a good starting point for the study of nonlinear water waves, are derived for deep water surface capillary gravity waves in the presence of second waves in which air is blowing over water. Here it is assumed that the space variation of the amplitude takes place only in a direction along which the group velocity projection of the two waves overlap. A stability analysis is made for a uniform wave train in the presence of a second wave train. Graphs are plotted for the maximum growth rate of instability wave number at marginal stability and wave number separation of fastest growing sideband component against wave steepness. Significant improvements are noticed from the results obtained from the two coupled third order nonlinear Schrödinger equations
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Engineering a replication-incompetent viral vector for the delivery of therapeutic RNA in crustaceans
Viral disease pandemics are a major cause of economic losses in crustacean farming worldwide. While RNA interference (RNAi)-based therapeutics have shown promise at a laboratory scale, without an effective oral delivery platform, RNA-based therapy will not reach its potential against controlling viral diseases in crustaceans. Using a reverse-engineered shrimp RNA virus, Macrobrachium rosenbergii nodavirus (MrNV), we have developed a shrimp viral vector for delivering an engineered RNA cargo. By replacing the RNA-dependent RNA polymerase (RdRp) protein-coding region of MrNV with a cargo RNA encoding green fluorescent protein (GFP) as a proof-of-concept, we generated a replication-incompetent mutant MrNV(ΔRdRp) carrying the GFP RNA cargo resulting in MrNV(ΔRdRp)-GFP. Upon incorporating MrNV(ΔRdRp)-GFP in the diet of the marine Pacific white shrimp (Penaeus vannamei), MrNV(ΔRdRp) particles were visualized in hemocytes demonstrating successful vector internalization. Fluorescence imaging of hemocytes showed the expression of GFP protein and the MrNV capsid RNA (RNA2) as well as the incorporated GFP RNA cargo. Detection of cargo RNA in hepatopancreas and pleopods indicated the systemic spread of the viral vector. The quantitative load of both the MrNV RNA2 and GFP RNA progressively diminished within 8 days postadministration of the viral vector, which indicated a lack of MrNV(ΔRdRp)-GFP replication in shrimp. In addition, no pathological hallmarks of the wild-type MrNV infection were detected using histopathology in the target tissue of treated shrimp. The data unequivocally demonstrated the successful engineering of a replication-incompetent viral vector for RNA delivery, paving the way for the oral delivery of antiviral therapeutics in farmed crustaceans. © The Author(s) 2023.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Predicting Powder Factor in Mixed-face Condition: Development of a Correlation based on Investigations in a Tunnel Through Basaltic Flows
Several approaches are available for estimating the powder factor in tunnel and bench blasting. These approaches consider those rock mass properties which are the most significant parameters in a rock--explosive interaction. However, they provide no information on the effects of mixed or multiple geological formations (mixed face) on the powder factor. Values for rock mass properties and the powder factor are collected along a length of 1075 m in the link tunnel of the Koyna Hydro-electric Project (Stage IV) in Maharashtra, India, which passes entirely through a mixed face and intersects more than one formation at a single location. A critical analysis of these data led to the development of a correlation for predicting the powder factor in the tunnel, considering uniaxial compressive strength, Barton's rock mass quality (Q), the thickness of each formation, and the effects of interformational contact surfaces
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