3,895 research outputs found
Introduction of Multipurpose Tree Species for Improving the Productivity of Grasslands in the Tropics
To improve the productivity of the Sahelian pastures, 10 different tree species were introduced and cattle, sheep and goats were allowed to graze. After a year of establishment, survival rate of different species ranged from 6% to 68%. Acacia senegal, Acacia seyal, Acacia nilotica, Combretum aculeata and Prosopis cineraria performed well and the impact of browsing by goats was severe
Seed abortion in Pongamia pinnata (Fabaceae)
In Pongamia pinnata only one of the two ovules develops into a seed in most of the pods. Since pollen was not found to be limiting and reduced fertilization could not completely explain the observed frequency of seed abortion, it implied an effect of postfertilization factors. Aqueous extracts of developing seeds and maternal tissue (placenta) did not influence abortion in vitro, suggesting that abortion may not be mediated by a chemical. Experimental uptake of 14C sucrose in vitro indicated that both the stigmatic and the peduncular seed have similar inherent capacities of drawing resources, but the peduncular seed is deprived of resources in the presence of the stigmatic seed. This deprivation of the peduncular seed could be offset by supplying an excess of hormones leading to the subsequent formation of two seeds in a pod. The prevalence of single-seeded pods in P. pinnata seems therefore to be a result of competition between the two seeds for maternal resources. The evolutionary significance of single-seeded pods in P. pinnata is discussed with respect to possible dispersal advantage enjoyed by such pods
Cocoa Care - An Android Application for Cocoa Disease Identification
India is an agricultural country. The correct and timely identification of diseases in crops is very much essential in agriculture. To obtain more valuable products, a product quality control is basically mandatory. Cocoa is an economically important crop that nowadays enlarges its production in southern India. To assist the farmers growing cocoa, we developed an android application Cocoa-Care. This application automatically identifies the diseases of cocoa crops, thereby helps the farmers who have little or no information about the disease. This application is developed by applying digital image processing techniques on the diseased cocoa images. Our approach replaces the manual disease inspection by the android application that identifies the cocoa disease from the captured image and suggests the possible remedies for the farmer. We used moment based texture features for the image representation and description. The matching is performed by nearest neighbor classifier. The results obtained are promising and this application can be used in the real time
Negative diffraction pattern dynamics in nonlinear cavities with left-handed materials
We study a ring cavity filled with a slab of a right-handed material and a
slab of a left-handed material. Both layers are assumed to be nonlinear Kerr
media. First, we derive a model for the propagation of light in a left-handed
material. By constructing a mean-field model, we show that the sign of
diffraction can be made either positive or negative in this resonator,
depending on the thicknesses of the layers. Subsequently, we demonstrate that
the dynamical behavior of the modulation instability is strongly affected by
the sign of the diffraction coefficient. Finally, we study the dissipative
structures in this resonator and reveal the predominance of a two-dimensional
up-switching process over the formation of spatially periodic structures,
leading to the truncation of the homogeneous hysteresis cycle.Comment: 8 pages, 5 figure
Metabolic pathway genes for editing to enhance multiple disease resistance in plants
Diseases are one of the major constraints in commercial crop production. Genetic diversity in varieties is the best option to manage diseases. Molecular marker-assisted breeding has produced hundreds of varieties with good yields, but the resistance level is not satisfactory. With the advent of whole genome sequencing, genome editing is emerging as an excellent option to improve the inadequate traits in these varieties. Plants produce thousands of antimicrobial secondary metabolites, which as polymers and conjugates are deposited to reinforce the secondary cell walls to contain the pathogen to an initial infection area. The resistance metabolites or the structures produced from them by plants are either constitutive (CR) or induced (IR), following pathogen invasion. The production of each resistance metabolite is controlled by a network of biosynthetic R genes, which are regulated by a hierarchy of R genes. A commercial variety also has most of these R genes, as in resistant, but a few may be mutated (SNPs/InDels). A few mutated genes, in one or more metabolic pathways, depending on the hostâpathogen interaction, can be edited, and stacked to increase resistance metabolites or structures produced by them, to achieve required levels of multiple pathogen resistance under field conditions
Acid-base properties of Cu<SUB>1-x</SUB>Co<SUB>x</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB> ferrospinels: FTIR investigations
Systematic IR spectroscopic studies were undertaken to investigate the acid-base properties of Cu-Co ferrospinels Cu1-xCoxFe2O4 (x=0 to 1) employed in phenol methylation to produce 2,6-xylenol. The IR spectra of the ferrospinels reveal that Fe3+ and Co2+ ions are mainly responsible for the various hydroxy groups on the surface. Temperature dependent IR studies of pyridine adsorbed on spinels and on the spinel phase with deliberately added metal oxide exemplify the contribution of the metal ions and their coordination state towards Lewis acidity. IR studies of the spinel surface with adsorbed CO2 and adsorption studies of electron acceptors such as 7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetrachloro-1-4-benzoquinone and p-dinitrobenzene were carried out to evaluate the nature of the basic sites and the strength and distribution of the electron donor sites present on the spinel surface. It was found that the acidity (basicity) of the Cu1-xCoxFe2O4 spinel system increases (decreases) from x=0 to 1. A correlation between acidity, basicity and catalytic performance reveals that an intermediate acid-base character enhances the phenol methylation activity
Apoptoticâlike PCD inducing HRC gene when silenced enhances multiple disease resistance in plants
Programmed cell death (PCD) plays an important role in plant environmental stress and has the potential to be manipulated to enhance disease resistance. Plants have innate immunity and, following pathogen perception, the host induces a Hypersensitive Response PCD (HR-PCD), leading to pattern (PTI) or effector triggered immunity (ETI). Here we report a non-HR type or Apoptotic-Like PCD (AL-PCD) in pathogen infected wheat and potato based on apoptotic-like DNA fragmentation. A deletion mutation in the gene encoding histidine rich calcium binding protein (TaHRC) in FHB-resistant wheat (R-NIL) failed to induce AL-PCD. Similarly, the CRISPR-Cas9 based silencing of StHRC gene in Russet Burbank potato failed to induce apoptotic-like DNA fragmentation, proved based on DNA laddering and TUNEL assays. The absence of AL-PCD in wheat R-NIL reduced pathogen biomass and mycotoxins, increasing the accumulation of resistance metabolites and FHB-resistance, and in potato
it enhanced resistance to multiple pathogens. In addition, the reduced expressions of metacaspase (StMC7) and Ca2+
dependent endonuclease 2 (StCaN2) genes in potato with Sthrc indicated an involvement of a hierarchy of genes in the induction of AL-PCD. The HRC in commercial varieties of
different crops, if functional, can be silenced by genome editing possibly to enhance resistance to multiple pathogens
Effect of charge distribution on the translocation of an inhomogeneously charged polymer through a nanopore
We investigate the voltage-driven translocation of an inhomogeneously charged
polymer through a nanopore by utilizing discrete and continuous stochastic
models. As a simplified illustration of the effect of charge distribution on
translocation, we consider the translocation of a polymer with a single charged
site in the presence and absence of interactions between the charge and the
pore. We find that the position of the charge that minimizes the translocation
time in the absence of pore--polymer interactions is determined by the entropic
cost of translocation, with the optimum charge position being at the midpoint
of the chain for a rodlike polymer and close to the leading chain end for an
ideal chain. The presence of attractive or repulsive pore--charge interactions
yields a shift in the optimum charge position towards the trailing end and the
leading end of the chain, respectively. Moreover, our results show that strong
attractive or repulsive interactions between the charge and the pore lengthen
the translocation time relative to translocation through an inert pore. We
generalize our results to accommodate the presence of multiple charged sites on
the polymer. Our results provide insight into the effect of charge
inhomogeneity on protein translocation through biological membranes.Comment: Submitted to Journal of Chemical Physic
Recent Innovations in Footwear and the Role of Smart Footwear in HealthcareâA Survey
© 2024 The Author(s). Licensee MDPI, Basel, Switzerland. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Smart shoes have ushered in a new era of personalised health monitoring and assistive technologies. Smart shoes leverage technologies such as Bluetooth for data collection and wireless transmission, and incorporate features such as GPS tracking, obstacle detection, and fitness tracking. As the 2010s unfolded, the smart shoe landscape diversified and advanced rapidly, driven by sensor technology enhancements and smartphonesâ ubiquity. Shoes have begun incorporating accelerometers, gyroscopes, and pressure sensors, significantly improving the accuracy of data collection and enabling functionalities such as gait analysis. The healthcare sector has recognised the potential of smart shoes, leading to innovations such as shoes designed to monitor diabetic foot ulcers, track rehabilitation progress, and detect falls among older people, thus expanding their application beyond fitness into medical monitoring. This article provides an overview of the current state of smart shoe technology, highlighting the integration of advanced sensors for health monitoring, energy harvesting, assistive features for the visually impaired, and deep learning for data analysis. This study discusses the potential of smart footwear in medical applications, particularly for patients with diabetes, and the ongoing research in this field. Current footwear challenges are also discussed, including complex construction, poor fit, comfort, and high cost.Peer reviewe
Mechanisms for Generating the Autonomous cAMP-Dependent Protein Kinase Required for Long-Term Facilitation in Aplysia
AbstractThe formation of a persistently active cAMP-dependent protein kinase (PKA) is critical for establishing long-term synaptic facilitation (LTF) in Aplysia. The injection of bovine catalytic (C) subunits into sensory neurons is sufficient to produce protein synthesisâdependent LTF. Early in the LTF induced by serotonin (5-HT), an autonomous PKA is generated through the ubiquitinâproteasome-mediated proteolysis of regulatory (R) subunits. The degradation of R occurs during an early time window and appears to be a key function of proteasomes in LTF. Lactacystin, a specific proteasome inhibitor, blocks the facilitation induced by 5-HT, and this block is rescued by injecting C subunits. R is degraded through an allosteric mechanism requiring an elevation of cAMP coincident with the induction of a ubiquitin carboxy-terminal hydrolase
- âŠ