Necessary and Sufficient Condition for the Solutions of First-Order Neutral Differential Equations to be Oscillatory or Tend to Zero

Santra, Shyam Sundar Department of Mathematics 2019 Kyungpook mathematical journal Vol.59 No.1

In this work, we give necessary and sufficient conditions under which every solution of a class of first-order neutral differential equations of the form $$(x(t)+p(t)x({\tau}(t)))^{\prime}+q(t)Hx({\sigma}(t)))=0$$ either oscillates or converges to zero as $t{\rightarrow}{\infty}$ for various ranges of the neutral coefficient p. Our main tools are the Knaster-Tarski fixed point theorem and the Banach's contraction mapping principle.

Nutrient Utilization and Compensatory Growth in Crossbred (Bos indicus×Bos taurus) Calves

Santra, A.,Pathak, N.N. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.8

A feeding trial was carried out over 238 days to determine the effect of compensatory growth in crossbred calves having 166 kg body weight. Fifteen crossbred calves were divided into two groups of five calves (G1 group) and ten calves (G2 group) as per randomized block design. Growth study was conducted on the feeding of wheat straw based diet containing 60 and 30 percent concentrate supplying equal amount of protein in group G1 and G2 respectively for 119 days (phase - I). At the end of phase-I, calves of G2 group were subdivided in to two groups (G3 and G4). One sub group (G4) received 60% concentrate in their diet (during 120 to 238 days of experiment) while other subgroup G3 received 30% concentrate in their diet (phase-II). The calves of G1 group continued to receive the same diet as during phase-I experiment. Mean DM intake was significantly higher in calves fed high level of concentrate (in G1 and G4 groups), which resulted in significantly higher digestibility of all nutrients except NDF. Nitrogen balance was positive in all the groups and showed significant differences in phase-II (higher nitrogen retention in G4 group than G1 group). ME intake was significantly affected by the level of dietary concentrate, being higher in high concentrate fed group (G1 and G4 than G2 and G3 group). Higher daily body weight gain in the calves of G4 group during phase-II than in G1 and G3 groups was due to compensatory growth on shifting animals from low concentrate to high concentrate based ration. Average daily body weight gain was higher in phase-I than in the phase-II. Protein and energy intake per unit body weight gain were significantly lower in calves fed high concentrate diet.

Human Non-neutralizing HIV-1 Envelope Monoclonal Antibodies Limit the Number of Founder Viruses during SHIV Mucosal Infection in Rhesus Macaques

Santra, Sampa,Tomaras, Georgia D.,Warrier, Ranjit,Nicely, Nathan I.,Liao, Hua-Xin,Pollara, Justin,Liu, Pinghuang,Alam, S. Munir,Zhang, Ruijun,Cocklin, Sarah L.,Shen, Xiaoying,Duffy, Ryan,Xia, Shi-Mao Public Library of Science 2015 PLoS pathogens Vol.11 No.8

<▼1><P>HIV-1 mucosal transmission begins with virus or virus-infected cells moving through mucus across mucosal epithelium to infect CD4<SUP>+</SUP> T cells. Although broadly neutralizing antibodies (bnAbs) are the type of HIV-1 antibodies that are most likely protective, they are not induced with current vaccine candidates. In contrast, antibodies that do not neutralize primary HIV-1 strains in the TZM-bl infection assay are readily induced by current vaccine candidates and have also been implicated as secondary correlates of decreased HIV-1 risk in the RV144 vaccine efficacy trial. Here, we have studied the capacity of anti-Env monoclonal antibodies (mAbs) against either the immunodominant region of gp41 (7B2 IgG1), the first constant region of gp120 (A32 IgG1), or the third variable loop (V3) of gp120 (CH22 IgG1) to modulate <I>in vivo</I> rectal mucosal transmission of a high-dose simian-human immunodeficiency virus (SHIV-BaL) in rhesus macaques. 7B2 IgG1 or A32 IgG1, each containing mutations to enhance Fc function, was administered passively to rhesus macaques but afforded no protection against productive clinical infection while the positive control antibody CH22 IgG1 prevented infection in 4 of 6 animals. Enumeration of transmitted/founder (T/F) viruses revealed that passive infusion of each of the three antibodies significantly reduced the number of T/F genomes. Thus, some antibodies that bind HIV-1 Env but fail to neutralize virus in traditional neutralization assays may limit the number of T/F viruses involved in transmission without leading to enhancement of viral infection. For one of these mAbs, gp41 mAb 7B2, we provide the first co-crystal structure in complex with a common cyclical loop motif demonstrated to be critical for infection by other retroviruses.</P></▼1><▼2><P><B>Author Summary</B></P><P>Antibodies specifically recognize antigenic sites on pathogens and can mediate multiple antiviral functions through engagement of effector cells via their Fc region. Current HIV-1 vaccine candidates induce polyclonal antibody responses with multiple antiviral functions, but do not induce broadly neutralizing antibodies. An improved understanding of whether certain types of non-neutralizing HIV-1 specific antibodies can individually protect against HIV-1 infection may facilitate vaccine development. Here, we test whether non-neutralizing antibodies with multiple antiviral functions mediated through FcR engagement and recognition of virus particles or virus-infected cells can limit infection, despite lacking classical virus neutralization activity. In a passive antibody infusion-rhesus macaque challenge model, we tested the ability of non-neutralizing monoclonal antibodies to limit virus acquisition. We demonstrate that two different types of non-neutralizing antibodies, one that recognizes both virus particles and infected cells (7B2) and another that recognizes only infected cells (A32) were capable of decreasing the number of transmitted founder viruses. Further, we provide the structure of 7B2 in complex with the gp41 cyclical loop motif, a motif critical for entry. These findings provide insights into the role that antibodies with antiviral properties, including virion capture and FcR mediated effector function, may play in protecting against HIV-1 acquisition.</P></▼2>

Effect of Level of Concentrate Supplement on Blood Biochemical Changes and Testosterone Level in Crossbred (Bos indicusi×Bos taurus) Calves

Santra, A.,Agarwal, N.,Kamra, D.N.,Pathak, N.N. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.6

A growth study was conducted for 238 days in twenty crossbred cattle calves to observe the effect of dietary concentrate supplement on blood biochemical changes and serum testosterone levels. The calves were divided into four groups (A, B, C and D) of five animals each. Calves of groups A and B were fed 60% and 30% concentrate, respectively, supplying equal amount of protein along with wheat straw. The calves in group C received 30% concentrate in their diet for 1 to 119 days of experiment and 60% concentrate during 120~238 days of experiment and vice versa in group D. Mean DM and TDN intake were significantly higher in group A than group B, C or D, resulted in higher daily growth rate in the former group. Blood glucose level was significantly higher in group A where as blood urea, hemoglobin, total protein, albumin, and globulin levels remained unchanged among the groups. Serum testosterone level increased with the increasing age of the animals but the level remained same in the animals of group A, B, C and D. A 30% concentrate diet does not have any severe adverse effect on the performance of crossbred cattle.

Fluorescent detection of palladium species with an <i>O</i>-propargylated fluorescein

Santra, Mithun,Ko, Sung-Kyun,Shin, Injae,Ahn, Kyo Han Royal Society of Chemistry 2010 Chemical communications Vol.46 No.22

<P>A fluorescein-based fluorescent probe displays fluorescence enhancement for palladium species in the typical oxidation states of 0, +2 and +4 and is applied to monitor accumulated palladium in living organisms.</P> <P>Graphic Abstract</P><P>The <I>O</I>-propargylated fluorescein undergoes a depropargylation reaction catalyzed by typical palladium species in the oxidation states of 0, +2 and +4 without additional additives, accompanied by a turn-on type fluorescence change; the probe is used for the fluorescent imaging of palladium chloride in zebrafish. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c001922d'> </P>

Rumen Manipulation to Improve Animal Productivity

Santra, A.,Karim, S.A. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.5

Anaerobic rumen microorganisms mainly bacteria, protozoa and fungi degrade ligno-cellulosic feeds consumed by the ruminants. The ruminants in developing countries are predominantly maintained on low grade roughage and grazing on degraded range land resulting in their poor nutrient utilization and productivity. Hence, manipulation of rumen fermentation was tried during last two decades to optimize ruminal fermentation for improving nutrient utilization and productivity of the animals. Modification of rumen microbial composition and their activity was attempted by using chemical additives those selectively effect rumen microbes, introduction of naturally occurring or genetically modified foreign microbes into the rumen and genetically manipulation of existing microbes in the rumen ecosystem. Accordingly, rumen protozoa were eliminated by defaunation for reducing ruminal methane production and increasing protein outflow in the intestine, resulting in improve growth and feed conversion efficiency of the animals. Further, Interspecies trans-inoculation of rumen microbes was also successfully used for annulment of dietary toxic factor. Additionally, probiotics of bacterial and yeast origin have been used in animal feeding to stabilize rumen fermentation, reduced incidence of diarrhoea and thus improving growth and feed conversion efficiency of young stalk. It is envisaged that genetic manipulation of rumen microorganisms has enormous research potential in developing countries. In view of feed resource availability more emphasis has to be given for manipulating rumen fermentation to increase cellulolytic activity for efficient utilization of low grade roughage.

Exponential Passivity Results for Singular Networked Cascade Control Systems Via Sampled-Data Control

Santra, Srimanta,Sakthivel, R.,Mathiyalagan, K.,Marshal Anthoni, S. ASME International 2017 Journal of Dynamic Systems, Measurement and Contro Vol. No.

A chemodosimeter approach to fluorescent sensing and imaging of inorganic and methylmercury species

Santra, Mithun,Ryu, Dowook,Chatterjee, Amrita,Ko, Sung-Kyun,Shin, Injae,Ahn, Kyo Han Royal Society of Chemistry 2009 Chemical communications Vol.2009 No.16

<P>A highly sensitive fluorescent turn-on probe specific for methylmercury species as well as inorganic mercury ions has been developed on the basis of mercury ion-promoted hydrolysis of a fluorescein-derived aryl vinyl ether.</P> <P>Graphic Abstract</P><P>A fluorescent turn-on probe specific for methylmercury as well as inorganic mercury ions has been developed on the basis of mercury ion-promoted hydrolysis of a fluorescein-derived aryl vinyl ether; the probe was used for fluorescent imaging of both CH<SUB>3</SUB>HgCl-contaminated cells and a living vertebrate organism, zebrafish. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b900380k'> </P>

Dissipative sampled-data controller design for singular networked cascade control systems

Santra, S.,Sakthivel, R.,Shi, Y.,Mathiyalagan, K. Pergamon Press [etc.] 2016 Journal of the Franklin Institute Vol.353 No.14

<P>This paper is concerned with the problem of dissipative fault-tolerant cascade control synthesis for a-class of singular networked cascade control systems (NCCS) with both differentiable and non-differentiable time varying delays. By constructing the appropriate Lyapunov-Krasovskii functional using the available information about the actual sampling pattern, a new set of sufficient condition is obtained to guarantee that the singular networked cascade control systems to be admissible and strictly (Q, S, R)-dissipative. Based on the criterion, a design algorithm for the desired sampled-data-cascade controller is formulated in terms of linear matrix inequalities. More precisely, Jensen's integral inequality together with Wirtinger-based inequality is used in derivation of the main result. From the obtained dissipative result, we deduce three cases namely H-infinity performance, passivity performance, mixed H-infinity and passivity performance for the considered singular NCCS. Finally, a power plant boiler-turbine system is given to demonstrate the effectiveness and applicability of the proposed design techniques. (C) 2016 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.</P>

A “Reactive” Ratiometric Fluorescent Probe for Mercury Species

Santra, Mithun,Roy, Basab,Ahn, Kyo Han American Chemical Society 2011 Organic letters Vol.13 No.13

<P>A ratiometric fluorescent probe for mercury species is developed based on the metal-promoted hydrolysis of a vinyl ether derivative of 2-(benzothiazol-2-yl)phenol in a buffer solution. The probe responds selectively to mercury species over various other metal ions with a marked fluorescence change from blue to cyan through the excited state intramolecular proton transfer (ESIPT) process. The fluorescence titration is complete with 0.5 equiv of HgCl<SUB>2</SUB>, which indicates that the probe also responds to organomercury species, RHgCl.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orlef7/2011/orlef7.2011.13.issue-13/ol2011693/production/images/medium/ol-2011-011693_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ol2011693'>ACS Electronic Supporting Info</A></P>