6,068 research outputs found

    Nitrogen release kinetics of organic nutrient sources in two benchmark soils of Indo-Gangetic plains

    Get PDF
    An understanding of the mineralization process of organic amendments in soil is required to synchronize N release with crop demand and protect the environment from excess N accumulation. Therefore, we conducted a laboratory incubation experiment to assess nitrogen mineralization potential of crop residues (rice and wheat straw) and organic manures (poultry manure, farmyard manure, cowpea and sesbania) in two benchmark soils (Typic Haplustept and Typic Ustifluvents) of semi-arid region of Punjab, India, varying in textureat field capacity moisture level at a constant temperature of 331°C. Mineralization was faster during first 7 days of incubation in Typic Haplustept and upto 14 days in Typic Ustifluvents which subsequently declined over time. In both soils, net N mineralization continued to increase with increasing period of incubation (expect with crop residues) and was significantly higher in Typic Ustifluvents (54-231”g g-1) than Typic Haplustept (33-203 ”g g-1). Compared to unamended soils, percent N mineralized was highest is sesbania (35-40 %) followed by cowpea (32-37 %) and least in wheat (10-11 %) after 42 days of incubation. Thus, sesbania and cowpea may preferably be used to meetthe large N demand during early period of plant growth. Further, mineralization rate constants (k) also indicated that availability of mineral N was significantly higher with application of organic amendments than unamended control treatments in both soils. Therefore, it may be concluded that considerable economy in the use of inorganic N fertilizer can be employed if N mineralization potential of organic inputs is taken into consideration

    The complex conformational dynamics of neuronal calcium sensor-1: A single molecule perspective

    Get PDF
    The human neuronal calcium sensor-1 (NCS-1) is a multispecific two-domain EF-hand protein expressed predominantly in neurons and is a member of the NCS protein family. Structure-function relationships of NCS-1 have been extensively studied showing that conformational dynamics linked to diverse ion-binding is important to its function. NCS-1 transduces Ca 2+ changes in neurons and is linked to a wide range of neuronal functions such as regulation of neurotransmitter release, voltage-gated Ca 2+ channels and neuronal outgrowth. Defective NCS-1 can be deleterious to cells and has been linked to serious neuronal disorders like autism. Here, we review recent studies describing at the single molecule level the structural and mechanistic details of the folding and misfolding processes of the non-myristoylated NCS-1. By manipulating one molecule at a time with optical tweezers, the conformational equilibria of the Ca 2+ -bound, Mg 2+ -bound and apo states of NCS-1 were investigated revealing a complex folding mechanism underlain by a rugged and multidimensional energy landscape. The molecular rearrangements that NCS-1 undergoes to transit from one conformation to another and the energetics of these reactions are tightly regulated by the binding of divalent ions (Ca 2+ and Mg 2+ ) to its EF-hands. At pathologically high Ca 2+ concentrations the protein sometimes follows non-productive misfolding pathways leading to kinetically trapped and potentially harmful misfolded conformations. We discuss the significance of these misfolding events as well as the role of inter-domain interactions in shaping the energy landscape and ultimately the biological function of NCS-1. The conformational equilibria of NCS-1 are also compared to those of calmodulin (CaM) and differences and similarities in the behavior of these proteins are rationalized in terms of structural properties

    Evaluation of rough lemon (Citrus jambhiri Lush.)as rootstock for salinity tolerance at seedling stage under in vitro conditions

    Get PDF
    In vitro approach was adopted to study the effect of salinity on survival and growth of rough lemon (Citrus jambhiri Lush.) seeds. North-West (Punjab) part of India has been facing a major problem of soil salinity for citrus orchards. Therefore, it is logical to study the salinity tolerance of common citrus rootstock, rough lemon (Citrus jambhiri Lush.), grown in the region. The seeds were treated with nine different doses of sodium salt. In all the treatments, leaves of rough lemon seedlings showed severe injury symptoms of chlorosis and necrosis while the seeds cultured in control did not show any injury. There was a significant decrease in seed germination, seedling height, internodal length, and subsequently plant weight with increasing concentration of salt. In contrast to the above characteristics, the length of primary roots increased proportionally with the increase in salt concentration in the culture media. As under stress conditions, the in vitro grown seedlings tend to increase the root length for its survival. In comparison to the control, salt treatments showed increased level of Na+ and Cl- ions in the seedlings and also resulted in a decrease of K+/Na+ ratio. Tolerance index was found minimum (100) in control and maximum in 154mM NaCl treatments after 4 and 8 weeks.Key words: Citrus, salt, sensitivity, chlorosis, sodium chloride

    Response of fennel (Foeniculum vulgare) to irrigation and mulching

    Get PDF
    A field experiment was conducted to find out the effect of irrigation levels and mulching on performance of fennel. Results indicated that application of six irrigations significantly increased the plant height, number of branches plant-1, total chlorophyll content, dry matter accumulation per metre row length, number of umbels plant-1, umbellets umbel-1, seeds umbellet-1 as well as seed, stover and biological yield of fennel compared to four and five irrigations. However, it remained at par with seven irrigations. Results further revealed that application of straw mulch significantly increased number of branches plant-1, dry matter accumulation per metre row length, number of umbellets umbel-1 and yields (seed, stover and biological) over control, dust and plastic mulches. Plant height and number of umbels plant-1 increased significantly with straw mulch as compared to control and dust mulch, but remained at par with plastic mulch. However, in respect of number of seeds umbellet-1, straw, plastic and dust mulch gave similar results. &nbsp

    Nanoscale Mechanical Drumming Visualized by 4D Electron Microscopy

    Get PDF
    With four-dimensional (4D) electron microscopy, we report in situ imaging of the mechanical drumming of a nanoscale material. The single crystal graphite film is found to exhibit global resonance motion that is fully reversible and follows the same evolution after each initiating stress pulse. At early times, the motion appears “chaotic” showing the different mechanical modes present over the micron scale. At longer time, the motion of the thin film collapses into a well-defined fundamental frequency of 1.08 MHz, a behavior reminiscent of mode locking; the mechanical motion damps out after ∌200 ÎŒs and the oscillation has a “cavity” quality factor of 150. The resonance time is determined by the stiffness of the material, and for the 75 nm thick and 40 ÎŒm square specimen used here we determined Young’s modulus to be 1.0 TPa for the in-plane stress−strain profile. Because of its real-time dimension, this 4D microscopy should have applications in the study of these and other types of materials structures

    Small intestinal mucosal cells in piglets fed with probiotic and zinc: a qualitative and quantitative microanatomical study

    Get PDF
    Background: Probiotics and zinc are commonly used and beneficial in pig production. This work aimed to assess the effects of probiotic and zinc on the mucosal cells of the small intestine in respect to digestive capacity and immunity in pre- and post-weaned piglets.Materials and methods: Eighteen Large White Yorkshire piglets were divided equally into control and treatment groups. The piglets were maintained in standard management conditions and were weaned at 28 days of age. The treatment group of piglets fed a mixture of probiotics orally at 1.25 × 109 CFU/day and zinc at 2000 ppm/day from birth to 10 days of age. At three different age-groups viz. day 20 (pre-weaning) and, day 30 and day 60 (post-weaning), the animals were sacrificed. For histomorphology, the tissue samples were processed and stained with Mayer’s haematoxylin and eosin for routine study, combined periodic acid-Schiff-Alcian blue for mucopolysaccharides and Masson-Hamperl argentaffin technique for argentaffin cells. The stained slides were observed under the microscope. The samples were processed as per the standard procedure for scanning and transmission electron microscopy. The statistical analysis of the data using the appropriate statistical tests was also conducted.Results: The mucosal epithelium of villi and crypts were lined by enterocytes, goblet cells, argentaffin cells, microfold (M-cell) cells, tuft cells and intraepithelial lymphocytes. The multipotent stem cells were located at the crypt base. The length of the enterocyte microvilli was significantly longer (p < 0.05) in the treatment group of piglets. The number of different types of goblet cells and argentaffin cells was more in treated piglets irrespective of segments of intestine and age. The intraepithelial lymphocytes were located in apical, nuclear and basal positions in the lining epithelium of both villus tip and base with their significant increase in the treatment group of piglets. The transmission electron microscopy revealed the frequent occurrence of tuft cells in the lining mucosa of the small intestine in treated piglets.Conclusions: Dietary supplementation of probiotic and zinc induced the number of different mucosal cells of villi and crypts in the small intestine that might suggest the greater absorptive capacity of nutrients and effective immunity in critical pre and post-weaned piglets

    Bell's inequalities in the tomographic representation

    Get PDF
    The tomographic approach to quantum mechanics is revisited as a direct tool to investigate violation of Bell-like inequalities. Since quantum tomograms are well defined probability distributions, the tomographic approach is emphasized to be the most natural one to compare the predictions of classical and quantum theory. Examples of inequalities for two qubits an two qutrits are considered in the tomographic probability representation of spin states.Comment: 11 pages, comments and references adde

    Weed management in coriander (Coriandrum sativum L.) at varying levels of nitrogen

    Get PDF
    A field experiment was conducted to study the effect of weed control treatments and nitrogen (N) levels on weed dynamics, weed control efficiency, nutrient depletion by weeds, yield of coriander and weed competition index. All the weed control treatments significantly reduced the density and dry weight of weeds and nutrient depletion as compared to weedy check. Oxadiargyl at 0.06 kg ha-1 + hand weeding (HW) at 40 days after sowing (DAS) represented the lowest weed density and controlled the weeds to the extent of 94.9%. Two hand weedings done at 20 and 40 DAS and pendimethalin at 1.0 kg ha-1 + HW at 40 DAS were found to be the most superior treatments in reducing density, intensity and dry weight of weeds and increasing weed control efficiency. These treatments controlled the weeds to the extent of 95.1% and 95.4%, respectively at harvest stage than weedy check and showed lower weed infestation of 17.4 and 18.1%, respectively. The lowest nutrient depletion due to weeds was obtained with pendimethalin at 1.0 kg ha-1 + HW at 40 DAS treatment which saved 54.80 kg N, 8.31 kg P and 49.22 kg K ha-1, respectively than weedy check. Two HWs at 20 and 40 DAS and oxadiargyl at 0.06 kg ha-1 + HW at 40 DAS also reduced the nutrient depletion to the extent of 94.8 and 94.5% of N; 95.0 and 94.7% of P and 94.9 and 94.6% of K, respectively in comparison to weedy check. Two hand weeding treatment gave the highest seed yield (1.37 t ha-1) among all the treatments and was closely followed by pendimethalin at 1.0 kg ha-1 + HW at 40 DAS which also increased the seed yield by a margin of 0.84 t ha-1 over weedy check, and registered the lowest weed competition index of 0.7%. &nbsp

    Neurotransmitters Drive Combinatorial Multistate Postsynaptic Density Networks

    Get PDF
    The mammalian postsynaptic density (PSD) comprises a complex collection of ~1100 proteins. Despite extensive knowledge of individual proteins, the overall organization of the PSD is poorly understood. Here, we define maps of molecular circuitry within the PSD based on phosphorylation of postsynaptic proteins. Activation of a single neurotransmitter receptor, the N-methyl-D-aspartate receptor (NMDAR), changed the phosphorylation status of 127 proteins. Stimulation of ionotropic and metabotropic glutamate receptors and dopamine receptors activated overlapping networks with distinct combinatorial phosphorylation signatures. Using peptide array technology, we identified specific phosphorylation motifs and switching mechanisms responsible for the integration of neurotransmitter receptor pathways and their coordination of multiple substrates in these networks. These combinatorial networks confer high information-processing capacity and functional diversity on synapses, and their elucidation may provide new insights into disease mechanisms and new opportunities for drug discover
    • 

    corecore