Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
1.
Br J Anaesth ; 119(4): 830-835, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29121291

RESUMEN

BACKGROUND: Pectoral nerve block1 (PEC1) given between pectoralis major and minor, and modified pectoral nerve block2 (mPEC2) performed between pectoralis minor and serratus anterior, can provide continuous analgesia after modified radical mastectomy (MRM) when catheters are placed before skin closure. This study was designed to compare PEC1 and mPEC2 block for providing postoperative pain relief after MRM. METHODS: Sixty-two physically fit patients undergoing MRM were assigned into two groups (Group PEC1, n=31 and Group mPEC2, n=31). Before wound closure, epidural catheter was placed in the group designated muscle plane and 30ml of 0.25% bupivacaine was injected through the catheter after wound closure. Bupivacaine 15ml of 0.25% top up was given on patient's demand or whenever visual analogue scale (VAS) score was>4. Time for first analgesia (TFA), number of top ups and VAS was recorded at 0.5, 6, 12, 18, 24 h after surgery. Sensory blockade was assessed 30 min after extubation. RESULTS: Analgesia was significantly prolonged in group mPEC2 [mean(SD)] 313.45(43.05) vs 258.87(34.71) min in group PEC1, P<0.001. Total pain experienced over 24 h was significantly less in group mPEC2 [mean(SD)] 9.77(6.93) than in group PEC1 24.19(10.81), P<0.0001. Consequently, top up requirements were significantly reduced in group mPEC2 than in group PEC1 [median(range)] 3(2-4) vs 4(3-5) respectively, P<0.001. Lateral pectoral (77.42% and 35.48%) and thoracodorsal nerves (93.55% and 48.39%) had higher incidence of sensory block in group mPEC2 than group PEC1, P<0.001. CONCLUSIONS: mPEC2 provides better postoperative analgesia than PEC1 when catheters are placed under direct vision after MRM. CLINICAL TRIAL REGISTRATION: CTRI/2017/02/007811 (REF/2015/11/010185).


Asunto(s)
Mastectomía Radical , Bloqueo Nervioso/métodos , Dolor Postoperatorio/prevención & control , Nervios Torácicos/efectos de los fármacos , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Resultado del Tratamiento
2.
Environ Technol ; 37(20): 2627-37, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26915419

RESUMEN

Solid waste management (SWM) is one of the most challenging issues owing to lack of authentic data on different elements of SWM, namely, storage, collection, transportation, separation, processing and disposal. This study presents an assessment of existing status of SWM in conjunction with municipal solid waste (MSW) generation rates, physical and chemical characterization of MSW in high-altitude sub-tropical regions. Weighing of empty and fully loaded trucks per trip revealed total quantity of MSW collected. The average efficiency of MSW collection was 70%. From the baseline data, it is inferred that the population and MSW generation rates are not co-related. The collected MSW included biodegradables (organic wastes), paper, plastic, glass, ceramics, metals, inert materials, ash and debris. The data analysis indicated that the biodegradable components dominate the characterization at 54.83% followed by inert, ash and debris at 21.06%, paper at 8.77%, plastic at 8.18%, glass and ceramics at 4.45% and metals at 2.71%. Statistical measures were also applied and 90% confidence interval (CI) was generated for the characterization data measuring its statistical significance.


Asunto(s)
Residuos Sólidos , Administración de Residuos/métodos , Altitud , Ambiente , India
3.
Phys Rev Lett ; 110(13): 137404, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23581371

RESUMEN

We use terahertz pulses to induce resonant transitions between the eigenstates of optically generated exciton populations in a high-quality semiconductor quantum well sample. Monitoring the excitonic photoluminescence, we observe transient quenching of the 1s exciton emission, which we attribute to the terahertz-induced 1s-to-2p excitation. Simultaneously, a pronounced enhancement of the 2s exciton emission is observed, despite the 1s-to-2s transition being dipole forbidden. A microscopic many-body theory explains the experimental observations as a Coulomb-scattering mixing of the 2s and 2p states, yielding an effective terahertz transition between the 1s and 2s populations.

4.
J Environ Sci Eng ; 55(1): 114-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25464714

RESUMEN

Solid waste management is one of the major problems of today's world and needs to be addressed by proper utilization of technologies and design of effective, flexible and structured information system. Therefore, the objective of this paper was to design and develop a GIS based solid waste management information system as a decision making and planning tool for regularities and municipal authorities. The system integrates geo-spatial features of the city and database of existing solid waste management. GIS based information system facilitates modules of visualization, query interface, statistical analysis, report generation and database modification. It also provides modules like solid waste estimation, collection, transportation and disposal details. The information system is user-friendly, standalone and platform independent.


Asunto(s)
Sistemas de Información Geográfica , Administración de Residuos , Ciudades , India
7.
Rev Sci Instrum ; 82(10): 103107, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22047280

RESUMEN

Time and wavelength resolved spectroscopy requires optical sources emitting very short pulses and a fast detection mechanism capable of measuring the evolution of the output spectrum as a function of time. We use table-top Ti:sapphire lasers and a free-electron laser (FEL) emitting ps pulses as excitation sources and a streak camera coupled to a spectrometer for detection. One of the major aspects of this setup is the synchronization of pulses from the two lasers which we describe in detail. Optical properties of the FEL pulses are studied by autocorrelation and electro-optic sampling measurements. We discuss the advantages of using this setup to perform photoluminescence quenching in semiconductor quantum wells and quantum dots. Carrier redistribution due to pulsed excitation in these heterostructures can be investigated directly. Sideband generation in quantum wells is also studied where the intense FEL pulses facilitate the detection of the otherwise weak nonlinear effect.

8.
Waste Manag ; 29(2): 883-95, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18595684

RESUMEN

Solid waste management is one of the most challenging issues in urban cities, which are facing a serious pollution problem due to the generation of huge quantities of solid waste. This paper presents an assessment of the existing situation of municipal solid waste management (MSWM) in major cities in India. The quantity and composition of MSW vary from place to place, and bear a rather consistent correlation with the average standard of living. Extensive field investigations were carried out for quantification, analysis of physical composition, and characterization of MSW in each of the identified cities. The MSW management status (per the MSW Rules, 2000) has also been assessed, and an action plan for better management has been formulated; both are presented in this paper. Studies carried out in 59 selected cities in India have revealed that there are many shortcomings in the existing practices used in managing the MSW. These shortcomings pertain mainly to inadequate manpower, financial resources, implements, and machinery required for effectively carrying out various activities for MSWM. To overcome the deficiencies in the existing MSWM systems, an indicative action plan has been presented incorporating strategies and guidelines. Based on this plan, municipal agencies can prepare specific action plans for their respective cities.


Asunto(s)
Ciudades , Administración de Residuos/métodos , Administración de Residuos/normas , Conservación de los Recursos Naturales , India , Política Pública , Transportes , Administración de Residuos/legislación & jurisprudencia
9.
Water Environ Res ; 80(2): 154-61, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18330226

RESUMEN

The effect of heavy metals on the activities of earthworm species Eudrillus eugineae was studied during vermicomposting of municipal solid waste (MSW) spiked with heavy metals. The activities of earthworms, in terms of growth and biomass production and number of cocoons produced, were monitored periodically, and the concentration of heavy metals in earthworms and substrates was determined at definite intervals. Laboratory-scale experiments were performed by mixing individual heavy metals in MSW. Copper, cadmium, chromium, lead, and zinc were selected for the study. The study concludes that heavy metals tend to accumulate in the body of earthworms; hence, the inherent concentration of heavy metals in the substrate before vermicomposting must be considered in view of composting of MSW and its application to soil. It was observed that copper and cadmium were toxic for the worms at 1.5 and 0.1 g/kg of the waste, respectively. The studies also suggest that earthworms are susceptible to the free form of heavy metals. Cadmium is the most toxic metal, followed by copper. Based on the investigation and observation, it was also found that earthworms should be separated from castings before the use of castings in soil amendments.


Asunto(s)
Metales Pesados/farmacología , Oligoquetos/efectos de los fármacos , Eliminación de Residuos/métodos , Contaminantes del Suelo/metabolismo , Suelo/parasitología , Agricultura , Animales , Biomasa , Cadmio/farmacología , Cadmio/toxicidad , Cobre/farmacología , Cobre/toxicidad , Relación Dosis-Respuesta a Droga , Plomo/farmacología , Plomo/toxicidad , Metales Pesados/toxicidad , Oligoquetos/crecimiento & desarrollo , Oligoquetos/metabolismo
10.
Waste Manag ; 28(1): 164-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17276666

RESUMEN

Biomethanation of municipal solid waste (MSW) is a slow process and the yield of biogas is usually low. Enhancement of acidification is necessary to increase the biogas yield in biomethanation of MSW. MSW contains a significant fraction of ligno-cellulosic material. The acidification of these materials influences the biogas yield. In the present study, hydrolysis and acidification have been considered as a combined phase. Experiments have been conducted to study the effect of recirculation of leachate on the acidification stage of the two-phase biomethanation process. Chemical oxygen demand (COD) and volatile fatty acid (VFA) were considered as indicator parameters. The study was also conducted to investigate the effect of using acid and alkali solution of 0.1% concentration in the acidification study. It was observed that daily recirculation of leachate does not have any major impact on the acidification process. It was also observed that treatment of MSW with sodium hydroxide yields leachate of significantly higher COD and VFA values compared to others.


Asunto(s)
Metano/química , Eliminación de Residuos/métodos , Ácidos , Reactores Biológicos , Ciudades , Concentración de Iones de Hidrógeno , Factores de Tiempo
11.
Bioresour Technol ; 99(14): 6512-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18155903

RESUMEN

An investigation was carried out in the laboratory to find out the microbial dynamics and enzyme activities during rapid composting of municipal solid waste (MSW). Various treatments such as aeration (A), addition of chemical agents (glucose (G) and acetic acid (AA) and application of cellulolytic microbial (M) inoculum (Phanerochaete chrysosporium and Trichoderma reesei) were used to facilitate the decomposition of MSW. The result of the present investigation revealed that the degradation of organic substrates were quick (within 9-12 days) in case of rapid composting as indicated by the reduction (below 20) in C/N ratio. Whereas, normal composting took more than 20 days to attain C/N ratio of below 20. Estimation of selected enzymes (amylase, protease, phosphatase and cellulase) provided information on the substrate specific degradation profiles of various labile substrates contained in organic waste.


Asunto(s)
Eliminación de Residuos/métodos , Suelo , Amilasas/metabolismo , Biomasa , Péptido Hidrolasas/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo
15.
Waste Manag Res ; 21(3): 249-61, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12870645

RESUMEN

Crude oil is a major source of energy and feedstock for petrochemicals. Oily sludge, bio-sludge and chemical sludge are the major sludges generated from the processes and effluent treatment plants of the refineries engaged in crude oil refining operations. Refineries in India generate about 28,220 tons of sludge per annum. Various types of pollutants like phenols, heavy metals, etc. are present in the sludges and they are treated as hazardous waste. Oily sludge, which is generated in much higher amount compared to other sludges, contains phenol (90-100 mg/kg), nickel (17-25 mg/kg), chromium (27-80 mg/kg), zinc (7-80 mg/kg), manganese (19-24 mg/kg), cadmium (0.8-2 mg/kg), copper (32-120 mg/kg) and lead (0.001-0.12 mg/ kg). Uncontrolled disposal practices of sludges in India cause degradation of environmental and depreciation of aesthetic quality. Environmental impact due to improper sludge management has also been identified. Salient features of various treatment and disposal practices have been discussed. Findings of a case study undertaken by the authors for Numaligarh Refinery in India have been presented. Various system alternatives have been identified for waste management in Numaligarh Refinery. A ranking exercise has been carried out to evaluate the alternatives and select the appropriate one. A detailed design of the selected waste management system has been presented.


Asunto(s)
Residuos Peligrosos , Petróleo , Eliminación de Residuos/métodos , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , India , Industrias , Metales Pesados/análisis , Estudios de Casos Organizacionales
16.
Biochem Pharmacol ; 62(9): 1293-7, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11705463

RESUMEN

Chlorpromazine (CPZ) is known to induce hyperglycaemia and can inhibit insulin secretion in both normal subjects and patients with latent diabetes mellitus. In this study, we have tried to determine a probable mechanism by which CPZ causes hyperglycaemia. It is possible that CPZ causes insulin aggregation by the reduction of disulphide bonds, thereby inactivating insulin and hence causing hyperglycaemia.


Asunto(s)
Clorpromazina/efectos adversos , Hiperglucemia/inducido químicamente , Insulina/metabolismo , Animales , Antipsicóticos/efectos adversos , Antipsicóticos/farmacología , Bovinos , Clorpromazina/farmacología , Humanos , Cinética
17.
Mol Cell Biochem ; 221(1-2): 11-5, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11506173

RESUMEN

The mode and nature of the binding of chlorpromazine (CPZ), a psychotropic drug, with milk proteins--alpha-lactalbumin (with substantial amounts of alpha-helix, beta-sheet and random coil), alpha-lactoglobulin (a major beta-sheeted protein) and alphas-casein (a random coiled protein) have been studied spectrofluorometrically and spectropolarimetrically. The binding affinity of CPZ for unfolded proteins is comparatively less than that of folded proteins although the number of binding sites is smaller in the latter case, due to the greater extent of binding of CPZ for folded proteins. Thermodynamic analysis reveals that CPZ binds to alpha-lactalbumin and alphas-casein in an endothermic (deltaH degrees is positive) and hydrophobic manner but with beta-lactoglobulin in an exothermic (deltaH degrees is negative) manner. Far UV Circular dichroic studies reveal that CPZ increases the secondary structure of the major beta-sheeted protein, beta-lactoglobulin possibly by increasing the relative contact orders (non-local contacts) within the residues. On the other hand, for proteins possessing random coil, it increases the unfolded state of the protein. CPZ does not affect local contacts in alpha-helix when its interaction is compared with a major alpha-helical protein, myoglobin.


Asunto(s)
Antipsicóticos/metabolismo , Clorpromazina/metabolismo , Proteínas de la Leche/química , Proteínas de la Leche/metabolismo , Sitios de Unión , Caseínas/química , Caseínas/metabolismo , Dicroismo Circular , Humanos , Lactalbúmina/química , Lactalbúmina/metabolismo , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Mioglobina/química , Mioglobina/metabolismo , Unión Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Espectrofotometría , Termodinámica
18.
J Pept Res ; 57(5): 428-34, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11350603

RESUMEN

The chaperone activity and biophysical properties of the 19 amino acid peptide DFVIFLDVKHFSPEDLTVK, identified as the functional element in alphaA-crystallin and here referred to as mini-alphaA-crystallin, were studied using light scattering and spectroscopic methods after altering its sequence and enantiomerism. The all-D and all-L conformers of the peptide do not show marked differences in their chaperone-like activity against heat-induced aggregation of alcohol dehydrogenase at 48 degrees C and dithiothreitol-induced aggregation of insulin. The retro peptide does not show any secondary structure and is also unable to act like a chaperone. Both all-L and all-D peptides lose their beta-sheet conformations, hydrophobicity and chaperone-like activity at temperatures > 50 degrees C. However, upon cooling, a significant portion of those properties was regained, suggesting temperature-dependent, reversible structural alterations in the peptides under investigation. We propose that both the hydrophobicity and beta-sheet conformation of the functional element of alphaA-crystallin are essential for chaperone-like activity.


Asunto(s)
Cristalinas/química , Chaperonas Moleculares/química , Secuencia de Aminoácidos , Dicroismo Circular , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Espectrofotometría Ultravioleta
19.
J Physiol Pharmacol ; 52(1): 145-52, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11321508

RESUMEN

Gram-negative sepsis often produces endotoxin (LPS) which causes infection. Reduction in tissue perfusion due to microcirculatory failure may lead to septic shock. We studied the effect of LPS on lipid peroxidation of erythrocyte. In vitro studies using 50 microg to 250 microg LPS/ml blood showed increased lipid peroxidation of erythrocyte in a dose-dependent manner. The increased effect of lipid peroxidation does not occur with LPS when erythrocytes were washed to remove plasma and leukocytes. Mannitol and glycerol, known scavengers of hydroxyl radical, arrest the elevation in lipid peroxidation of erythrocytes after LPS treatment. Hemolysis of erythrocytes was reduced with low doses of LPS. Plasma lipid peroxidation was elevated after treatment of blood with LPS. From the results we suggest that the peroxidation of erythrocyte lipid caused by LPS may probably play a role in the production of septic shock.


Asunto(s)
Eritrocitos/efectos de los fármacos , Glicerol/farmacología , Peroxidación de Lípido/efectos de los fármacos , Lipopolisacáridos/farmacología , Manitol/farmacología , Animales , Relación Dosis-Respuesta a Droga , Eritrocitos/metabolismo , Lipopolisacáridos/sangre , Ratas
20.
Indian J Exp Biol ; 38(2): 160-6, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11218833

RESUMEN

We have attempted a new evaluation of the process of conjugation in bacteria, because of some basic dissimilarities observed between this and that of eukaryotes, or plants and animals. Reference donor and recipient strains, widely used to prove conjugation in bacteria, were chosen; addition of DNase during the conjugation process, led to an unexpected but highly reproducible increase in the transconjugant colony counts (TCC; ca. > or = 1 log), when compared with that of the controls without DNase. Transconjugants were also obtained when the same live donors were substituted with the UV-killed ones although the TCC was very low initially. Contrarily, donors treated with DNA-intercalating agents, e.g. acridine orange or ethidium bromide, resulted in a complete failure to produce transconjugants. There was a quantitative relationship between the DNase used on donors and levels of DNA sugars/nucleotides/DNA, which possibly resulted from interaction between the DNase and DNA being present/produced on the donor surface. This may be indicative of what may actually happen in the donor-recipient mixtures in the conjugation test proper, where the recipient DNase may activate a donor DNA production cycle. The evidences presented did not suggest that the donor DNA in the conjugation process is actually vestibuled through any intercellular conjugation passages, and is susceptible to the action of DNase or the intercalating dyes.


Asunto(s)
Conjugación Genética , Animales , Conjugación Genética/efectos de los fármacos , ADN Bacteriano/metabolismo , Desoxirribonucleasas/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Fimbrias Bacterianas/genética , Técnicas de Transferencia de Gen
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA