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1.
Nature ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048015

RESUMEN

Of the ~25 directly imaged planets to date, all are younger than 500Myr and all but 6 are younger than 100Myr1. Eps Ind A (HD209100, HIP108870) is a K5V star of roughly solar age (recently derived as 3.7-5.7Gyr2 and 3.5 - 1.3 + 0.8 Gyr3). A long-term radial velocity trend 4,5 as well as an astrometric acceleration6,7 led to claims of a giant planet2,8,9 orbiting the nearby star (3.6384±0.0013pc10). Here we report JWST coronagraphic images that reveal a giant exoplanet which is consistent with these radial and astrometric measurements, but inconsistent with the previously claimed planet properties. The new planet has temperature ~275K, and is remarkably bright at 10.65µm and 15.50µm. Non-detections between 3.5-5µm indicate an unknown opacity source in the atmosphere, possibly suggesting a high metallicity, high carbon-to-oxygen ratio planet. The best-fit temperature of the planet is consistent with theoretical thermal evolution models, which are previously untested at this temperature range. The data indicates that this is likely the only giant planet in the system and we therefore refer to it as "b", despite it having significantly different orbital properties than the previously claimed planet "b".

2.
J Therm Spray Technol ; 31(1-2): 307-314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37520905

RESUMEN

The abradable coatings had significantly enhanced turbomachinery performance by acting as a sacrificial seal between rotating blades and stationary casing. Further improvement in seal design to meet the higher energy demand and increase the service time has been the key challenge to solve in the gas turbine industry. Honeycomb seals have become the industry standard clearance seal technique due to their unique design and high structural strength with minimum weight. The present study proposes a concept to form a thermal shock resistance structure to achieve higher temperature capability and improve the reliability of high-temperature abradable seal structures for a hot gas path of turbines. A cavity layer of honeycomb seal structure made of SS 321 alloy was coated with advanced high-temperature ZrO2 + 7.5%Y2O3 + 4% polyester seal material using TriplexPro-210 plasma spray system. The integrity of a seal structure was assessed by a cross-sectional analysis and evaluation of the coating microstructure. Additionally, the micro-hardness test was performed to estimate coating fracture toughness, and finite element analysis was used to assess its thermo-mechanical performance. The concept proposed in this study should be further validated to develop the most capable innovative technology for advanced gas turbine abradable seal structures.

3.
Trop Anim Health Prod ; 50(5): 1025-1032, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29442255

RESUMEN

The present study was formulated to find out the status of important season related thermal stress biomarkers of pure-bred (Hampshire) and crossbred (50% Hampshire × 50% local) pigs under the agro-climatic condition of Assam State, India. The experiment was also aimed to study the role of different level of energy ration (110, 100, and 90% energy of NRC feeding standard for pig) in variation of physiological and biochemical parameters in two genetic groups of pigs in different seasons. The metabolizable energy value were 3260, 2936.5, and 3585.8 kcal/kg in grower ration and 3260.2, 2936.6, and 3587 kcal/kg in finisher ration for normal energy (NE), low energy (LE) and high energy (HE), respectively. Both the genetic group of animals were housed separately under intensive system of management. Each pen was measuring 10' × 12' along with an outer enclosure. Six weaned piglets (almost similar body weight of average 10.55 kg) of each group were kept in a separate pen. However, after attainment of 35 kg body weight, the animals of a group were divided in two pens of three animals each. The present experiment indicated that average ambient temperature during summer months (27.33-29.51 °C) was above the comfort zone for pigs (22 °C). The significantly (P < 0.01) higher relative humidity (RH) (%) was recorded in outdoor environment (87.26-91.10%) and in the morning time (86.60-91.10%). The temperature humidity index (THI) during the study period was found to be indicative of thermal stress to the experimental animals during summer (79.55-82.56). Physiological parameters viz., respiration rate (RR) and rectal temperature (RT) were significantly (P < 0.01) higher in summer season (43.75-72.12 breaths/min. and 102.29-103.23 °F) and non-significantly higher values were recorded in Hampshire pigs. It was also found that the significantly (P < 0.01) lower RR as well as RT was recorded in the pigs fed with high energy (HE) ration during summer season. Serum triiodothyronine (T3) and thyroxine (T4) concentrations were significantly (P < 0.01) lower during summer, while both the genetic groups showed significantly (P < 0.01) higher concentration of serum cortisol during summer season. It was also observed that thyroid hormone and cortisol concentrations were maintained in groups of pig fed vegetable oil incorporated HE diet during summer. From the present study, it is found that the increasing the energy level of the ration might be helpful to minimize the effects of thermal stress during summer.


Asunto(s)
Ingestión de Energía , Humedad , Hidrocortisona/sangre , Estaciones del Año , Destete , Animales , Biomarcadores/sangre , Temperatura Corporal/fisiología , Peso Corporal , Dieta/veterinaria , Femenino , India , Masculino , Porcinos , Temperatura , Hormonas Tiroideas/sangre , Clima Tropical
4.
J Phys Chem A ; 118(22): 3996-4004, 2014 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-24815040

RESUMEN

Straight chain amide N,N-dihexyloctanamide (DHOA) has been found to be a promising alternative extractant to tri-n-butyl phosphate (TBP) for the reprocessing of irradiated uranium- and thorium-based fuels. Unlike TBP, DHOA displays preferential extraction of Pu(IV) over U(VI) at higher acidities (≥3 M HNO3) and poor extraction at lower acidities. Density functional theory (DFT) based calculations have been carried out on the structures and relative binding energies of U(VI) and Pu(IV) with the extractant molecules. These calculations suggest that the differential hardness of the two extractants is responsible for the preferential binding/complexation of TBP to uranyl, whereas the softer DHOA and the bulky nature of the extractant lead to stronger binding/complexation of DHOA to Pu(IV). In conjunction with quantum chemical calculations, small angle neutron scattering (SANS) measurements have also been performed for understanding the stoichiometry of the complex formed that leads to relatively lower extraction of Th(IV) (a model for Pu(IV)) as compared to U(VI) using DHOA and TBP as the extractants. The combined experimental and theoretical studies helped us to understand the superior complexation/extraction behavior of Pu(IV) over U(VI) with DHOA.

5.
Eur J Mass Spectrom (Chichester) ; 19(4): 275-83, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24575626

RESUMEN

Laser desorption/ionization-time-of-flight mass spectrometry (LDI-ToF-MS) has been applied to identify and characterize the organic phase species formed during the extraction of thorium nitrate by 1.1 M tri-n-butyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) solutions in n-dodecane. The aqueous phase thorium concentrations (at 4M HNO3) have been suitably chosen to get Loaded organic phases with/without third-phase. The extracted species have been characterized for the first time using LDI-ToF-MS. The results show feasibility of the use of this technique for understanding the extraction mechanisms and third-phase formation behavior of different extractants. The different chemical species observed using this technique are consistent with those observed by small-angle neutron scattering (SANS).

6.
Trop Anim Health Prod ; 45(7): 1513-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23636408

RESUMEN

The present study was conducted to know the smallholder pig production system in tribal areas of Sikkim State, India. Two hundred tribal farmers were selected randomly from the North and East District of the state. Information on socio-economic characteristics of farmers (gender, occupation, educational status, and farming experience), management practices, disease prevalence, and economics in pig production was collected. The study recorded the mean land holding as 1.2 ± 0.8 ha, and the number of pigs per farm was 5.0 ± 0.28. Pigs were mainly kept as a source of income, and 70 % of farmers reared crossbreed pigs. Ninety percent (90 %) of respondents practiced the intensive system of management whereby kitchen wastes along with cooked mixture comprising maize bhusa, mustard oil cake, pseudostem of banana, tuber, stem, and plant leaves were used to feed their animals. About 40.5 % of farmers procured their breeding stock from government farms that had good records and utilized veterinary services like timely vaccination and deworming. The diseases prevalent in the study area were swine fever, diarrhea, helminthoses, sarcoptic mange, pneumonia, etc. The litter sizes at birth (local, 4.3 ± 0.45; crossbreed, 7.2 ± 0.33), at weaning (local, 2.79 ± 0.24; crossbreed, 6.1 ± 0.21), and age at first farrowing (local, 365.39 ± 7.96 days; crossbreed, 337.24 ± 8.79 days) were recorded. Production costs of meat extracted from local and crossbred pigs were 1.08 $/kg and 0.86 $/kg, respectively.


Asunto(s)
Alimentación Animal/análisis , Crianza de Animales Domésticos/métodos , Carne/economía , Reproducción , Enfermedades de los Porcinos/epidemiología , Porcinos , Crianza de Animales Domésticos/economía , Animales , Dieta/veterinaria , Tamaño de la Camada , Prevalencia , Sikkim/epidemiología , Encuestas y Cuestionarios , Porcinos/crecimiento & desarrollo , Porcinos/fisiología , Enfermedades de los Porcinos/etiología
7.
J Healthc Qual Res ; 38(2): 76-83, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36163149

RESUMEN

INTRODUCTION AND OBJECTIVES: Using the assessment of satisfaction of patients of labour room services, the caregiver or policymakers can identify the gaps in the implemented programmes and health policies. This study was aimed to design a valid and reliable satisfaction questionnaire that will help in identifying the aspects of gaps that need improvement. METHODS: A facility and community-based observational cross-sectional study was conducted in the district of western Uttar Pradesh (India) between January 2019 and August 2020. Validation of the structured questionnaire with 34 dichotomous questions categorized under five subscales was performed by evaluating its validity and reliability. A total of 380 beneficiaries were selected from 48 government health facilities. RESULTS: The calculated Content validity index was calculated to be 9.5 which was adequate as per the guidelines. The reliability analysis of the questionnaire showed that the internal consistency was high with an overall Cronbach's alpha of 0.710. The variation in Cronbach's alpha on the elimination of any question from the questionnaire ranged from 0.676 to 0.767. The mean patient satisfaction score in the total surveyed population was 24.39±4.684 (total score=34) and there was a greater variation in the satisfaction score of infrastructure when compared with other subscales. CONCLUSION: The findings from this study support the reliability and validity of the patient satisfaction questionnaire as it is capable of evaluating the satisfaction in terms of delivery services provided in labour rooms as a whole.


Asunto(s)
Instituciones de Salud , Satisfacción Personal , Humanos , Estudios Transversales , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
8.
Indian J Biochem Biophys ; 49(1): 63-70, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22435146

RESUMEN

The effect of magnetic field (MF) treatments of maize (Zea mays L.) var. Ganga Safed 2 seeds on the growth, leaf water status, photosynthesis and antioxidant enzyme system under soil water stress was investigated under greenhouse conditions. The seeds were exposed to static MFs of 100 and 200 mT for 2 and 1 h, respectively. The treated seeds were sown in sand beds for seven days and transplanted in pots that were maintained at -0.03, -0.2 and -0.4 MPa soil water potentials under greenhouse conditions. MF exposure of seeds significantly enhanced all growth parameters, compared to the control seedlings. The significant increase in root parameters in seedlings from magnetically-exposed seeds resulted in maintenance of better leaf water status in terms of increase in leaf water potential, turgor potential and relative water content. Photosynthesis, stomatal conductance and chlorophyll content increased in plants from treated seeds, compared to control under irrigated and mild stress condition. Leaves from plants of magnetically-treated seeds showed decreased levels of hydrogen peroxide and antioxidant defense system enzymes (peroxidases, catalase and superoxide dismutase) under moisture stress conditions, when compared with untreated controls. Mild stress of -0.2 MPa induced a stimulating effect on functional root parameters, especially in 200 mT treated seedlings which can be exploited profitably for rain fed conditions. Our results suggested that MF treatment (100 mT for 2 h and 200 for 1 h) of maize seeds enhanced the seedling growth, leaf water status, photosynthesis rate and lowered the antioxidant defense system of seedlings under soil water stress. Thus, pre sowing static magnetic field treatment of seeds can be effectively used for improving growth under water stress.


Asunto(s)
Campos Magnéticos , Hojas de la Planta/química , Hojas de la Planta/enzimología , Plantones/efectos de la radiación , Semillas/efectos de la radiación , Agua/metabolismo , Zea mays/crecimiento & desarrollo , Catalasa/metabolismo , Catalasa/efectos de la radiación , Clorofila/metabolismo , Clorofila/efectos de la radiación , Deshidratación , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/efectos de la radiación , Peroxidasas/metabolismo , Peroxidasas/efectos de la radiación , Fotosíntesis/efectos de la radiación , Hojas de la Planta/efectos de la radiación , Lluvia , Plantones/crecimiento & desarrollo , Suelo , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/efectos de la radiación
9.
Nat Commun ; 12(1): 922, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33568657

RESUMEN

Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared observing approach that enables imaging low-mass temperate exoplanets around nearby stars, and in particular within the closest stellar system, α Centauri. Based on 75-80% of the best quality images from 100 h of cumulative observations, we demonstrate sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A. This is an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits. We also discuss a possible exoplanet or exozodiacal disk detection around α Centauri A. However, an instrumental artifact of unknown origin cannot be ruled out. These results demonstrate the feasibility of imaging rocky habitable-zone exoplanets with current and upcoming telescopes.

10.
Opt Express ; 18(3): 2719-28, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20174101

RESUMEN

The photoluminescence spectra from a quantum-dot exciton weakly-coupled to a planar photonic-crystal cavity is experimentally investigated by temperature tuning. Significant resonance shifts of the cavity mode are observed as the cavity mode spectrally approaches that of the exciton mode, showing the appearance of cavity-to-exciton attraction or mode pulling. Cavity-mode spectral shifts are also found theoretically using a master equation model that includes incoherent pump processes for the coupled exciton and cavity, pure dephasing, and allows for photon emission via radiation modes and the leaky cavity mode. Both experiments and theory show clear cavity mode spectral shifts in the photoluminescence spectra, when certain coupling parameters are met. However, discrepancies between the experimental data and theory, including more pronounced spectral shifts in the measurements, indicate that other unknown mode-pulling effects may also be occurring.

12.
J Biosoc Sci ; 41(3): 381-98, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-18845026

RESUMEN

This paper examines the trends in utilization of five indicators of reproductive and child health services, namely, childhood immunization, medical assistance at delivery, antenatal care, contraceptive use and unmet need for contraception, by wealth index of the household in India and two disparate states, Uttar Pradesh and Maharashtra. The data from three rounds of the National Family and Health Survey conducted during 1992-2005 are analysed. The wealth index is computed using principal component derived weights from a set of consumer durables, land size, housing quality and water and sanitation facilities of the household, and classified into quintiles for all three rounds. Bivariate analyses, rich-poor ratio and concentration index are used to understand the trends in utilization of, and inequality in, reproductive and child health services. The results indicate huge disparities in utilization of these services, largely to the disadvantage of the poor. Utilization of basic childhood immunization among the poorest and the poor stagnated in India, as well as in both states, during 1998-2005 compared with 1992-1998. The use of maternal care services such as medical assistance at delivery and antenatal care remained at a low level among the poor over this period. However, contraceptive use increased relatively faster among the poor, even with higher unmet need. Of all these services, the inequality in medical assistance at delivery is consistently large, while that of contraceptive use is small. The state-level differences in service coverage by wealth quintiles over time are large.


Asunto(s)
Servicios de Salud del Niño/estadística & datos numéricos , Servicios de Salud Reproductiva/estadística & datos numéricos , Factores Socioeconómicos , Niño , Preescolar , Femenino , Disparidades en Atención de Salud , Humanos , Inmunización/estadística & datos numéricos , India/epidemiología , Lactante , Masculino
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 73(2): 348-52, 2009 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-19329353

RESUMEN

N,N,N',N'-tetraoctyl diglycolamide (TODGA) has been identified as one of the promising extractants for the partitioning of minor actinides from high-level nuclear waste solutions. Solvent extraction studies have shown that stoichiometry of the extracted species of Eu(3+) with TODGA depend on the nature of diluent. Time resolved luminescence spectroscopy (TRLS) has been employed to investigate the complexation of Eu(3+) with TODGA under different experimental conditions. The effects of different experimental parameters such as aqueous phase acidity, nature of diluent, and TODGA concentration on the luminescence lifetime of Eu(3+) ions have been investigated. The lifetime measurements of the complexed fraction of Eu(3+) with TODGA suggested the absence of water molecules in the inner coordination sphere of the metal ion in different solvents. In ethanol-water (60/40%) mixture, the complexation of Eu(3+) with TODGA under varying ligand-to-metal ratios suggested the formation of 1:1, 1:2, and 1:3 species, viz., Eu(TODGA)(3+), Eu(TODGA)(2)(3+), and Eu(TODGA)(3)(3+), respectively. The conditional stability constants logbeta(1), logbeta(2), and logbeta(3) were calculated as 6.1+/-0.5, 10.8+/-0.7, and 14.3+/-0.6, respectively. The nature of diluent did not influence the luminescence spectra of Eu(3+) in the presence of TODGA.


Asunto(s)
Europio/química , Glicolatos/química , Concentración de Iones de Hidrógeno , Luminiscencia , Ácido Nítrico/química , Solventes/química , Espectrometría de Fluorescencia
14.
Eur J Med Res ; 13(8): 388-98, 2008 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-18952522

RESUMEN

OBJECTIVE: Advanced Glycation Endproducts (AGEs), implicated as one of the major causes of diabetic complications, either directly or via receptor mediated actions, trigger downstream events in the conduit vessels, microvascular bed as well as myocardium leading to microvascular and cardiac dysfunction. The aim of this study was to characterise the activity profile of TRC4149, a novel AGE breaker compound, to determine its ability to reduce the burden of AGEs in vitro and in vivo and to evaluate whether the reduced AGE burden could translate into improvement in hemodynamic function in a model of Streptozotocin induced diabetic Spontaneously Hypertensive Rats (SHR). METHOD: AGEs were prepared in vitro by incubating BSA and lysozyme with glucose or ribose while AGE-LDL was generated by copper catalyzed LDL oxidation. TRC4149 was evaluated using in vitro assays to determine its capacity to reduce the burden of AGEs and to test its antioxidant activity. To study the effect of TRC4149 on hemodynamic function, diabetic SHR implanted with telemetry transmitter were treated with TRC4149 (20 mg/kg i.p., b.i.d.) or vehicle for 14 weeks. Losartan was administered once per week and blood pressure was monitored telemetrically throughout the treatment period. Cardiac indices of systolic and diastolic function were assessed terminally using MacLab system. AGE load in aorta was determined immunohistochemically and VCAM expression was quantitated by real time PCR analysis. RESULTS: TRC4149 was able to break preformed AGEs as well as reduce further AGE accumulation in vitro in a dose dependent manner. It also demonstrated a potent free radical scavenging activity. In diabetic SHR, treatment with TRC4149 retarded the decline in response to losartan over the study period, and also improved cardiac function as evidenced by an improved dP/dtmax/min, left ventricular systolic pressure and decreased left ventricular diastolic pressure as compared to untreated group. AGE load as well as VCAM expression in aorta was also reduced upon treatment. CONCLUSIONS: TRC4149, a novel AGE-breaker compound, by virtue of reducing AGE load preserved endothelial and cardiac function in diabetic SHR, a model that recapitulates the microvascular and cardiac dysfunction associated with hypertension along with long-term diabetes.


Asunto(s)
Antioxidantes/farmacología , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Productos Finales de Glicación Avanzada/metabolismo , Hidrazinas/farmacología , Sulfonamidas/farmacología , Animales , Presión Sanguínea , Colágeno/química , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/patología , Ensayo de Inmunoadsorción Enzimática , Hemodinámica/efectos de los fármacos , Masculino , Modelos Biológicos , Modelos Químicos , Ratas , Ratas Endogámicas SHR , Ratas Wistar , Espectrometría de Fluorescencia/métodos
15.
Indian J Biochem Biophys ; 45(4): 269-74, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18788478

RESUMEN

Many types of invisible electromagnetic waves are produced in our atmosphere. When these radiations penetrate our body, electric fields are induced inside the body, resulting in the absorption of power, which is different for different body parts and also depends on the frequency of radiations. Higher power absorption may result into health problems. In this communication, effects of electromagnetic waves (EMW) of 41 and 202 MHz frequencies transmitted by the TV tower have been studied on skin, muscles, bone and fat of human. Using international standards for safe exposure limits of specific absorption rate (SAR), we have found the safe distance from TV transmission towers for two frequencies. It is suggested that transmission towers should be located away from the thickly populated areas and people should keep away from the transmission towers, as they radiate electromagnetic radiations that are harmful to some parts/tissues of body.


Asunto(s)
Tejido Adiposo/efectos de la radiación , Huesos/efectos de la radiación , Campos Electromagnéticos/efectos adversos , Músculos/efectos de la radiación , Ondas de Radio/efectos adversos , Piel/efectos de la radiación , Televisión , Salud Ambiental , Humanos , Modelos Biológicos , Radiación , Medición de Riesgo , Irradiación Corporal Total
16.
Chem Commun (Camb) ; 54(83): 11668-11680, 2018 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-30255866

RESUMEN

With this Feature Article we review, for the first time, the development of DNA-host conjugates-a nascent yet rapidly growing research focus within the ambit of DNA supramolecular chemistry. Synthetic hosts (such as cyclodextrins, cucurbiturils, and calixarenes) are well-suited to be partnered with DNA, since DNA assembly and host-guest binding both thrive in aqueous media, are largely orthogonal, and exhibit controllable and input-responsive properties. The covalent braiding of these two supramolecular synthons thus leads to advanced self-assemblies and nanostructures with exciting function that range from drug delivery agents to input-triggered switches. The latter class of DNA-host conjugates have been demonstrated to precisely control protein activity, and have also been used as modulable catalysts and versatile biosensors.


Asunto(s)
ADN/química , Compuestos Macrocíclicos/química , Nanoestructuras/química , Animales , Técnicas Biosensibles/métodos , Calixarenos/síntesis química , Calixarenos/química , Ciclodextrinas/síntesis química , Ciclodextrinas/química , ADN/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Técnicas de Transferencia de Gen , Humanos , Compuestos Macrocíclicos/síntesis química , Modelos Moleculares , Nanotecnología/métodos
17.
J Environ Biol ; 28(1): 83-6, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17717991

RESUMEN

Distinct morphophysiological variations observed for over 2 years with-in short distances among four perennial plants indicated genetic diversity among the lines growing at three places. The isozyme and SDS polyacrylamide gel banding patterns as genetic markers were used to investigate four perennial species, namely Dalbergia sissoo Roxb., Delonix regia (Boj.) Refin., Cassia fistula L. and Calotropis procera R. Br. Plant materials collected from three locations (Agra, Gwalior and Lucknow) differing in climo-edaphic variables were examined for 4 enzyme systems, viz., esterase, polyphenol oxidase, peroxidase and superoxide dismutase (EST, PPO, PRX and SOD). Among the four isozymes SOD and PRX revealed best discriminating power. Protein banding patterns as well as zymogram revealed that Dalbergia sissoo growing at Gwalior was closer to that of Agra; Delonix regia depicted highest similarity between Lucknow and Agra and Calotropis procera of Lucknow location was more closer to Gwalior than Agra. The results confirm genetic diversity in the species as a means of adaptation to differing climo-edaphic variables.


Asunto(s)
Apocynaceae/genética , Catecol Oxidasa/genética , Fabaceae/genética , Oxidorreductasas/genética , Alelos , Apocynaceae/enzimología , Ecosistema , Fabaceae/enzimología , Variación Genética , Genotipo , India , Isoenzimas/genética , Proteínas de Plantas/genética
19.
Indian J Biochem Biophys ; 42(2): 122-6, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23923573

RESUMEN

Electrolyte leakage from leaves and NMR transverse relaxation time (T2) of leaf water were used to differentiate between heat-tolerant (NIAW 845) and susceptible (HD 2428) wheat (Triticum aestivum L.) cultivars. The leaves were exposed to high temperature shock in the range 30 to 55 degrees C and the damage caused, when evaluated by the two approaches was in close agreement. The critical temperature of injury leading to loss of membrane integrity was lower (39.1 degrees C) for susceptible cultivar, compared to tolerant cultivar (44.2 degrees C). Component analyses of NMR data revealed the existence of two fractions of cellular water in leaf tissues, namely, bound and free bulk water with distinct relaxation times. A dramatic reduction in the proportion of free water and a corresponding increase in bound water was observed in response to increase in temperature. This change in proportion occurred around 38 degrees C and 43 degrees C in HD 2428 and NIAW 845 respectively. The high temperature induced irreversible damage to cellular membrane integrity led to loss of compartmentation of cellular water fractions. The tolerant cultivar maintained its membrane integrity and cell water compartmentation until a temperature of 43 degrees C and susceptible could maintain it only until 38 degrees C.


Asunto(s)
Membrana Celular/química , Calor , Espectroscopía de Resonancia Magnética , Hojas de la Planta/metabolismo , Protones , Estrés Fisiológico , Triticum/metabolismo , Membrana Celular/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Triticum/crecimiento & desarrollo
20.
Stroke ; 32(10): 2426-32, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11588337

RESUMEN

BACKGROUND AND PURPOSE: "Stress" hyperglycemia may be associated with increased mortality and poor recovery in diabetic and nondiabetic patients after stroke. A systematic review and meta-analysis of the literature relating acute poststroke glucose levels to the subsequent course were done to summarize and quantify this relationship. METHODS: A comprehensive literature search was done for cohort studies reporting mortality and/or functional recovery after stroke in relation to admission glucose level. Relative risks in hyperglycemic compared with normoglycemic patients with and without diabetes were calculated and meta-analyzed when possible. RESULTS: Thirty-two studies were identified; relative risks for prespecified outcomes were reported or could be calculated in 26 studies. After stroke of either subtype (ischemic or hemorrhagic), the unadjusted relative risk of in-hospital or 30-day mortality associated with admission glucose level >6 to 8 mmol/L (108 to 144 mg/dL) was 3.07 (95% CI, 2.50 to 3.79) in nondiabetic patients and 1.30 (95% CI, 0.49 to 3.43) in diabetic patients. After ischemic stroke, admission glucose level >6.1 to 7.0 mmol/L (110 to 126 mg/dL) was associated with increased risk of in-hospital or 30-day mortality in nondiabetic patients only (relative risk=3.28; 95% CI, 2.32 to 4.64). After hemorrhagic stroke, admission hyperglycemia was not associated with higher mortality in either diabetic or nondiabetic patients. Nondiabetic stroke survivors whose admission glucose level was >6.7 to 8 mmol/L (121 to 144 mg/dL) also had a greater risk of poor functional recovery (relative risk=1.41; 95% CI, 1.16 to 1.73). CONCLUSIONS: Acute hyperglycemia predicts increased risk of in-hospital mortality after ischemic stroke in nondiabetic patients and increased risk of poor functional recovery in nondiabetic stroke survivors.


Asunto(s)
Diabetes Mellitus , Hiperglucemia/diagnóstico , Estrés Fisiológico , Accidente Cerebrovascular/diagnóstico , Glucemia , Complicaciones de la Diabetes , Diabetes Mellitus/sangre , Mortalidad Hospitalaria , Humanos , Hiperglucemia/sangre , Hiperglucemia/etiología , Valor Predictivo de las Pruebas , Pronóstico , Riesgo , Medición de Riesgo , Estrés Fisiológico/sangre , Estrés Fisiológico/complicaciones , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/complicaciones , Tasa de Supervivencia
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