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1.
Dalton Trans ; 53(12): 5435-5452, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38412059

RESUMO

Grid-scale energy storage solutions are necessary for using renewable energy sources efficiently. A supercapattery (supercapacitor + battery) has recently been introduced as a new variety of hybrid devices that engage both capacitive and faradaic charge storage processes. Nano-chain architectures of Ni0.5Co0.5S electrode materials consisting of interconnected nano-spheres are rationally constructed by tailoring the surface structure. Nano-chains of the bimetallic sulfide Ni0.5Co0.5S are presented to have a superior charge storage capacity. The Ni0.5Co0.5S nano-chain electrode presents a capacitance of 2001.6 F g-1 at 1 mV s-1, with a specific capacity of 267 mA h g-1 (1920 F g-1) at 1 A g-1 in 4 M KOH aqueous electrolyte through the galvanostatic charge-discharge (GCD) method. The reason behind the high charge storage capacity of the materials is the predominant redox-mediated diffusion-controlled pseudocapacitive mechanism coupled with surface capacitance (electrosorption), as the surface (outer) and intercalative (inner) charges stored by the Ni0.5Co0.5S electrodes are close to 46.0% and 54.0%, respectively. Additionally, a Ni0.5Co0.5S//AC two electrode full cell operating in asymmetric supercapacitor cell (ASCs) mode in 4 M KOH electrolyte exhibits an impressive energy density equivalent to 257 W h kg-1 and a power density of 0.73 kW kg-1 at a current rate of 1 A g-1.

2.
Phys Chem Chem Phys ; 25(1): 555-569, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36484154

RESUMO

Currently, enhancing the performance of electrochemical supercapacitors is the subject of intense research to fulfill the ever-increasing demand for grid-scale energy storage and delivery solution, thereby utilizing the full potential of renewable energy resources and decreasing our dependence on fossil fuels. Metal sulfides, such as cobalt sulfide (CoS), nickel sulfide (NiS), molybdenum sulfide (MoS), copper sulfide (CuS), and others, have recently emerged as a promising class of active electrode materials, alongside other supercapacitor electrode materials, due to their relatively high specific capacitance values and exceptional reversible redox reaction activities. The synthesis, characterizations, and electrochemical performances of single-phase nanocrystalline ß-NiS are presented here and the electrode based on this material shows a specific capacitance of 1578 F g-1 at 1 A g-1 from the galvanostatic discharge profile, whereas a capacitance of 1611 F g-1 at 1 mV s-1 was obtained through the CV curve in 2 M KOH aqueous electrolyte. Additionally, the electrode also performs well in neutral 0.5 M Na2SO4 electrolytes resulting in specific capacitance equivalent to 403 F g-1 at 1 mV s-1 scan rate. The high charge storage capacity of the material is due to the superior intercalative (inner) charge storage coupled with the surface (outer) charges stored by the ß-NiS electrode and was found to be 72% and 28%, respectively, in aqueous 2 M KOH electrolyte. This intercalative charge storage mechanism is also responsible for its excellent cycling stability. Additionally, we assembled aqueous asymmetric supercapacitors (ASCs) with activated carbon (AC) as the negative electrode and the ß-NiS electrode as the positive electrode. The combination of the ß-NiS electrode and AC with excellent cycling stability resulted in the highest specific energy equivalent to ∼163 W h kg-1 and a specific power of ∼507 W kg-1 at 1 A g-1 current rate.

3.
RSC Adv ; 12(29): 18685-18696, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35873343

RESUMO

Nanoporous zinc borate (ZB) and 10% lanthanum-doped porous zinc borate (LZB) were synthesized to explore the role of porosity and doping in zinc borate during lubrication. HR-SEM, TEM, and HR-TEM authenticated nanoporous structures. The tribological properties of their blends with paraffin oil (PO) were compared by employing ASTM D4172 and ASTM D5183 norms on a four-ball tester. Vanadium selenide nanosheets (VSe2) were used to reinforce the structure of LZB for further advancement of the tribological properties. The superiority of the LZB/VSe2 over LZB and VSe2 nanosheets could be adjudged by tribological data. The porosity and lanthanum doping have yielded commendable tribological activity. The VSe2 nanosheets have strengthened the LZB matrix. The other constituent oxides of tribofilm from the LZB matrix, based on EDX analysis and XPS studies of the worn surface, ZnO, B2O3, La2O3, and V2O5, have abetted lubrication. The AFM and SEM investigations of wear track corroborated the tribological results.

4.
Phys Chem Chem Phys ; 24(18): 11066-11078, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471404

RESUMO

Pseudocapacitors offer both high energy and high power, making them suitable for grid-scale electrochemical energy storage to harness renewable energy produced from sun, wind, and tides. To overcome performance degradation in terms of cycling fading and lower specific capacitance values at high charge/discharge rates of electrochemical pseudocapacitors based on transition-metal oxides, perovskite-structured SrFeO3-δ was envisaged as a negative electrode that harnesses the Fe4+/3+ and Fe3+/2+ redox couple to deliver superior performance. SrFeO3-δ offers high specific capacitances of ca. 733 F g-1 at a scan rate of 1 mV s-1 and ca. 743 F g-1 at a current density of 1 A g-1 and demonstrates excellent cyclic stability over 2500 repeated cycles with capacitance retention of >92%, achieving 94% coulombic efficiency. The good cycling stability is attributed to the inherent metallic electrical conductivity of SrFeO3-δ and the fortuitous tendency of the robust cation framework structure to accommodate flexible oxygen content. The surface capacitive and diffusion-controlled contributions for capacitance are about ∼30% and ∼70%, respectively, at peak current and a scan rate equivalent to 1 mV s-1. The higher capacitance and stable performance make SrFeO3-δ an economical and abundant pseudocapacitive electrode.

5.
J Phys Condens Matter ; 30(40): 405803, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30160652

RESUMO

We report detailed investigations on the structural, magnetic, magneto-transport and calorimetric aspects of a partially ordered Heusler compound Pd2MnIn. The sample shows antiferomagnetic (AFM) state below around 120 K, though positive paramagnetic Curie temperature signifies a complex magnetic ground state with the presence of both ferromagnetic (FM) and AFM correlations. A clear spin-flop type metamagnetic transition is observed as evident from the magnetization and resistivity data. However, non-saturation of magnetization even at 145 kOe of applied field implies that the high field state may be a spin canted state, originating from the enhanced FM correlations by field induced conduction electron spin polarization. The sample shows a profound quadratic temperature dependence of resistivity below about 20-25 K indicating a spin-fluctuation dominated low temperature region. Previous electronic structure calculations show the existence of a subtle balance between superexchange mediated AFM state and an RKKY (Ruderman-Kittel-Kasuya-Yoshida) interaction mediated FM state in Pd2MnIn. Such competing AFM-FM correlations can be accounted for the observed spin fluctuations.

6.
South Asian J Cancer ; 7(1): 21-23, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29600228

RESUMO

BACKGROUND: Incidental gallbladder carcinoma (IGBC) is rare cancer diagnosed during or after cholecystectomy done for benign gallbladder disease. The concern whether routine histopathological examination is needed for all cholecystectomy specimens still remains debatable. MATERIALS AND METHODS: Twenty patients diagnosed with IGBC over a period of 2 years were retrospectively reviewed. Clinical details including clinical presentation, preoperative ultrasound (USG) findings, and macroscopic features were retrieved. Diagnosis of IGBC was confirmed on microscopic examination, and staging was done using the tumor node metastasis staging system. RESULTS: Of the 4800 cholecystectomy specimens retrieved, diagnosis of IGBC was rendered in twenty cases (0.41%). Mean patient age was 50.65 years with a female preponderance. Preoperative USG detected an increase in wall thickness in six cases (30%) in contrast to gross examination which revealed the same in 55% (11/20) cases. Mucosal ulceration was observed in two cases (10%) of IGBC and seven cases (35%) did not reveal any preoperative or macroscopic findings suggestive of malignancy. Associated cholelithiasis was observed in 14 cases. Final diagnosis of IGBC was made on histomorphological assessment with tumor cells infiltrating the lamina propria in three cases (pT1b), muscularis propria in 15 cases (pT1b), and serosa in the remaining 2 cases (pT2). CONCLUSION: IGBC is a clinical masquerader which often evades the eye of a radiologist and comes as pathological surprise. Histopathological examination of cholecystectomy specimens remains the gold standard for the detection of this occult, yet notorious malignancy and assessment of the depth of invasion in IGBC guide further management.

7.
Indian J Cancer ; 54(1): 362-367, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199724

RESUMO

INTRODUCTION: Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults. The standard management has been maximum surgical resection followed by adjuvant radiotherapy with concurrent chemotherapy followed by adjuvant chemotherapy. Although the survival rate of patients with GBM has improved with recent advancements in treatment, the prognosis remains generally poor. The median survival rates are in the range of 9-12 months and 2-year survival rates are in the range of 8%-12%. MATERIALS AND METHODS: A single-institution retrospective review of 61 patients of GBM from 2012 to 2014. Data regarding patient factors, disease factors, and treatment factors were collected and survival has been calculated. RESULTS: A total of 61 patients with GBM were analyzed. GBM is commonly seen in sixth decade of life. Male to female ratio is 2.6:1. The right side of the brain is commonly involved with right frontal lobe being the most common site. The median follow-up was 4.6 months. The median survival of our patients was 8 months. The 1-year and 2-year survival rates were 20% and 3.27%, respectively. CONCLUSIONS: The overall survival and prognosis in patients with GBM remains poor despite of constant research and studies. Concurrent chemoradiotherapy followed by adjuvant chemotherapy with temozolomide should be used after maximal resection to improve the survival.


Assuntos
Glioblastoma/epidemiologia , Glioblastoma/radioterapia , Prognóstico , Adulto , Idoso , Quimiorradioterapia , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/cirurgia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Estudos Retrospectivos , Temozolomida , Adulto Jovem
8.
Eye (Lond) ; 30(11): 1462-1468, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27419839

RESUMO

PurposeInternational variations in visual acuity (VA) outcomes of eyes treated for neovascular age-related macular degeneration (nAMD) are well-documented, but intra-country inter-centre regional variations are not known. These data are important for national quality outcome indicators. We aimed to determine intra-country and inter-centre regional variations in outcomes for treatment of nAMD.Patients and methodsProspective multicentre national database study of 13 UK centres that treated patients according to a set protocol (three loading doses, followed by Pro-Re-Nata retreatment). A total of 5811 treatment naive eyes of 5205 patients received a total of 36 206 ranibizumab injections over 12 months.ResultsMean starting VA between centres varied from 48.9 to 59.9 ETDRS letters. Mean inter-centre VA change from baseline to 12 months varied from +6.9 letters to -0.6 letters (mean of +2.5 letters). The proportion of eyes achieving VA of 70 letters or more varied between 21.9 and 48.7% at 12 months. Median number of injections (visits) at each centre varied from 5 to 8 (9 to 12), with an overall median of 6 (11). Age, starting VA, number of injections, and visits, but not gender were significantly associated with variation in these VA outcomes (P<0.01). Significant variation between centres persisted even after adjusting for these factors.ConclusionThere are modest differences in VA outcomes between centres in the UK. These differences are influenced, but not completely explained, by factors such as patient age, starting VA, number of injections, and visits. These data provide an indication of the VA outcomes that are achievable in real-world settings.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Ranibizumab/uso terapêutico , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Masculino , Estudos Prospectivos , Retratamento , Resultado do Tratamento , Reino Unido , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/efeitos dos fármacos , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/fisiopatologia
9.
Clin Genet ; 90(6): 496-508, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27146977

RESUMO

Mucopolysaccharidoses (MPS), a subgroup of lysosomal storage disorders, are caused due to deficiency of specific lysosomal enzyme involved in catabolism of glycosaminoglycans. To date more than 200 pathogenic variants in the alpha-l-iduronidase (IDUA) for MPS I and ∼500 pathogenic variants in the iduronate-2-sulphatase (IDS) for MPS II have been reported worldwide. The mutation spectrum of MPS type I and MPS type II disorders in Indian population is not characterized yet. In this study, we carried out clinical, biochemical, molecular and in silico analyses to establish the mutation spectrum of MPS I and MPS II in the Indian population. We conducted molecular analysis for 60 MPS-affected patients [MPS I (n = 30) (Hurler syndrome = 17, Hurler-Scheie syndrome = 13), and MPS II (n = 30) (severe = 18, attenuated = 12)] and identified a total of 44 [MPS I (n = 22) and MPS II (n = 22)] different pathogenic variants comprising missense, nonsense, frameshift, gross deletions and splice site variants. A total of 20 [MPS I (n = 14), and MPS II (n = 6)] novel pathogenic sequence variants were identified in our patient cohort. We found that 32% of pathogenic variants detected in IDUA were recurrent and 25% in MPS II. This is the first study revealing the mutation spectrum of MPS I and MPS II patients in the Indian population.


Assuntos
Glicoproteínas/genética , Iduronidase/genética , Mucopolissacaridose II/genética , Mucopolissacaridose I/genética , Mutação/genética , Adolescente , Criança , Pré-Escolar , Feminino , Glicoproteínas/química , Humanos , Iduronidase/química , Índia , Lactente , Masculino , Mucopolissacaridose I/fisiopatologia , Mucopolissacaridose II/fisiopatologia , Fenótipo , Conformação Proteica , Deleção de Sequência/genética , Relação Estrutura-Atividade
10.
Paediatr Int Child Health ; 35(2): 160-3, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25311880

RESUMO

Idiopathic systemic capillary leak syndrome is a rare and life-threatening disorder of unknown pathology. It results from leakage of plasma from the intravascular into the interstitial space and is characterised by recurrent episodes of shock, weight gain and generalised oedema. Recurrent episodes of this syndrome are reported in a 6-year-old girl who presented with the characteristic symptoms of shock, oedema and hypoalbuminaemia. She was treated effectively with fluid resuscitation, ionotropes and intravenous immunoglobin. Since systemic capillary leak syndrome is rare and the diagnosis is often missed, further research regarding its pathogenesis and treatment in children is warranted.


Assuntos
Síndrome de Vazamento Capilar/diagnóstico , Síndrome de Vazamento Capilar/patologia , Síndrome de Vazamento Capilar/terapia , Criança , Feminino , Hidratação/métodos , Humanos , Imunoglobulinas Intravenosas/administração & dosagem
11.
Am J Respir Crit Care Med ; 190(11): 1263-72, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25333685

RESUMO

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is an untreatable and often fatal lung disease that is increasing in prevalence and is caused by complex interactions between genetic and environmental factors. Epigenetic mechanisms control gene expression and are likely to regulate the IPF transcriptome. OBJECTIVES: To identify methylation marks that modify gene expression in IPF lung. METHODS: We assessed DNA methylation (comprehensive high-throughput arrays for relative methylation arrays [CHARM]) and gene expression (Agilent gene expression arrays) in 94 patients with IPF and 67 control subjects, and performed integrative genomic analyses to define methylation-gene expression relationships in IPF lung. We validated methylation changes by a targeted analysis (Epityper), and performed functional validation of one of the genes identified by our analysis. MEASUREMENTS AND MAIN RESULTS: We identified 2,130 differentially methylated regions (DMRs; <5% false discovery rate), of which 738 are associated with significant changes in gene expression and enriched for expected inverse relationship between methylation and expression (P < 2.2 × 10(-16)). We validated 13/15 DMRs by targeted analysis of methylation. Methylation-expression quantitative trait loci (methyl-eQTL) identified methylation marks that control cis and trans gene expression, with an enrichment for cis relationships (P < 2.2 × 10(-16)). We found five trans methyl-eQTLs where a methylation change at a single DMR is associated with transcriptional changes in a substantial number of genes; four of these DMRs are near transcription factors (castor zinc finger 1 [CASZ1], FOXC1, MXD4, and ZDHHC4). We studied the in vitro effects of change in CASZ1 expression and validated its role in regulation of target genes in the methyl-eQTL. CONCLUSIONS: These results suggest that DNA methylation may be involved in the pathogenesis of IPF.


Assuntos
Metilação de DNA/genética , Epigênese Genética/fisiologia , Fibrose Pulmonar Idiopática/genética , Locos de Características Quantitativas/genética , Transcriptoma/genética , Corticosteroides/uso terapêutico , Estudos de Casos e Controles , Feminino , Expressão Gênica , Marcadores Genéticos , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fumar/epidemiologia
12.
Indian J Otolaryngol Head Neck Surg ; 66(3): 232-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25032106

RESUMO

Serum Antistreptolysin O (ASO) titre is raised when there is infection of any organ of the body, by Group A beta haemolytic streptococci (GABHS), Group C or Group G streptococci [1]. Increased serum ASO titre should not be the only deciding criterion for tonsillectomy if GABHS is not present in the palatine tonsils. In this study, we evaluate the rationality of performing tonsillectomy in raised serum ASO titre only, in absence of GABHS in palatine tonsil. The study was designed as a prospective cohort study in which the main out come measure is to find out: The main outcome measure is to find out whether only the raised serum ASO titre is to be considered to perform tonsillectomy or not. Fifty consecutive patients (both children and adults) clinically diagnosed to have chronic tonsillitis were included in this prospective cohort study. Throat swab culture, tonsilar core tissue culture and Serum ASO titre tests were performed in all the patients. The results showed that out of the 50 patients 45 had raised ASO titre and 5 patients had normal ASO titre. GABHS was found in 5 cases (10 %) in throat swab culture and 8 cases (16 %) in FNA of tonsil core culture. The sensitivity of throat swab culture as compared to FNA Tonsil core culture was 62.5 % and positive predictive value was 100 %. The sensitivity of ASO titre as compared to core culture was 100 % and positive predictive value was 17.8 %. Specificity was only 12 %. From the results of this study, it is evident that FNA culture of the tonsil core is a valid and a reliable test for the diagnosis of bacterial micro flora in recurrent tonsillitis. One should perform throat swab culture and FNA culture from tonsil core along with ASO titre before doing tonsillectomy in absence of any other indications. Identifying GABHS in the tonsil by FNA test and/or in the throat swab culture along with high serum ASO titre may be one of the ideal indications for tonsillectomy.

13.
Plant Dis ; 98(9): 1267, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30699648

RESUMO

Flax or linseed is grown as a fiber or oilseed crop in tropical and temperate regions. It is commercially cultivated in many countries of the world including Canada, China, India, the United States, Ethiopia, Pakistan, Russia, Poland, and Argentina (1). In December 2013, symptoms suggestive of phytoplasma infection were noticed on flax in different experimental fields of Central Research Institute for Jute and Allied Fibres (CRIJAF) research farm, Barrackpore, India, and the incidence was less than 2%. Because incidence of phytoplasma diseases are increasing worldwide, occurrence of a phytoplasma in a new geographical area poses an imminent threat. The infected plants showed floral virescence, phyllody, and stem fasciation (flattened stem). Floral malformation was very conspicuous with abnormal structures replacing normal flowers. All the floral parts, including petals, turned into green leaves. Total DNA was extracted from leaf mid veins of three symptomatic and three asymptomatic plants using a DNeasy Plant Mini Kit (Qiagen). PCR was carried out with the phytoplasma-specific universal P1/P7 primer set followed by nested primer pair R16F2n/R16R2 (2), resulting in DNA amplicons that were 1.8 kb and 1.2 kb, respectively, in all symptomatic samples tested. No amplification was observed with DNA from symptomless samples. This suggested association of a phytoplasma with the disease. The five purified nested PCR products were cloned in a pGEM-T Easy vector (Promega) and sequenced. One of the sequences that proved to be identical to the others was deposited in GenBank (Accession No. KJ417660). The consensus sequence was analyzed by NCBI BLAST and found to share 99% similarity with the 16Sr DNA sequence of the 'Candidatus Phytoplasma asteris' reference strain (GenBank HQ828108), which belongs to 16SrI group. The phylogenetic tree based on 16SrDNA sequence of phytoplasmas belonging to group 16SrI and other distinct phytoplasma groups also showed that the phytoplasma clustered with members of group 16SrI (3). The nested PCR product of R16F2n/R16R2 was digested using restriction enzymes AluI, BfaI, BstU, HhaI, HpaI, KpnI, MseI, and RsaI. The RFLP patterns were compared with those of known phytoplasma strains (2) and they matched the patterns for aster yellows subgroup B (16Sr I-B). Subsequently, the iPhyClassifier 16Sr group/subgroup classification based on similarity (4) analyses showed that the studied strain had 16SrDNA sequences in the 16SrI-B group with a similarity coefficient of 1.00. To the best of our knowledge, this is the first report of 16SrI-B phytoplasma associated with flax in India. References: (1) K. P. Akhtar et al. Phytoparasitica 41:383, 2013. (2) I. M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (3) N. Saitou and M. Nei. Mol. Biol. Evol. 4:406, 1987. (4) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

15.
ACS Appl Mater Interfaces ; 5(7): 2455-61, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23461478

RESUMO

In this article, we have investigated the effect of oxygen partial pressure (PO2) and film thickness on defect-induced room-temperature (RT) ferromagnetism (FM) of highly c-axis orientated p-type Na-doped ZnO thin films fabricated by pulse laser deposition (PLD) technique. We have found that the substitution of Na at Zn site (NaZn) can be effective to stabilize intrinsic ferromagnetic (FM) ordering in ZnO thin films with Curie temperature (TC) as high as 509 K. The saturation magnetization (MS) is found to decrease gradually with the increase in thickness of the films, whereas an increase in "MS" is observed with the increase in PO2 of the PLD chamber. The enhancement of ferromagnetic signature with increasing PO2 excludes the possibility of oxygen vacancy (VO) defects for the magnetic origin in Na-doped ZnO films. On the other hand, remarkable enhancement in the green emission (IG) are observed in the photoluminescence (PL) spectroscopic measurements due to Na-doping and that indicates the stabilization of considerable amount of Zn vacancy (VZn)-type defects in Na-doped ZnO films. Correlating the results of PL and X-ray photoelectron spectroscopy (XPS) studies with magnetic measurements we have found that VZn and Na substitutional (NaZn) defects are responsible for the hole-mediated FM in Na-doped ZnO films, which might be an effective candidate for modern spintronic technology.

16.
ACS Appl Mater Interfaces ; 4(4): 2048-56, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22423973

RESUMO

The effects of rare-earth-element Gd doping on the intrinsic magnetic ordering, photoluminescence, and electrical-conducting properties of the pristine SnO(2) nanocrystalline thin films fabricated by radio-frequency (RF) sputtering are investigated. The pristine SnO(2) thin film exhibits significant ferromagnetism while Gd doping results in an absence of intrinsic ferromagnetism. The presence of large amounts of singly ionized oxygen vacancies (V(O)(+)) is traced by photoluminescence spectroscopic analysis and they are found to be responsible for the observed ferromagnetism in pristine SnO(2) thin films. A significant reduction of oxygen vacancies is observed after Gd doping, and that might be insufficient to mediate long-range ferromagnetic ordering between V(O)(+) defects in a Gd-doped SnO(2) system. Although the associated magnetic moment is increased by 1 order of magnitude, because of the insertion of Gd(3+) ions, which have localized f-shell paramagnetic moment, there is no intrinsic FM ordering. Hall measurement reveals that the pure SnO(2) exhibits n-type behavior whereas Gd-doped SnO(2) films show the p-type conductivity with higher resistivity. The studies demonstrate that only structural defects such as V(O)(+) defects, not magnetic ions such as Gd(3+), are responsible for inducing ferromagnetism in SnO(2) thin films.

17.
Environ Monit Assess ; 184(6): 3427-41, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21701887

RESUMO

Dust from haul and transport roads are the major source of air pollution in opencast coal mining areas. Dust generated during mining operations pollutes air which causes different health problems. Various available techniques are implemented in the field to minimize and control dust in mining areas. However, they are not very effective because dust deposited on road surfaces are not removed by these techniques. For effective control of dust in opencast mining areas, it has to be regularly collected from road surfaces and may be converted into solid form, and subsequently can be used as a domestic fuel considering its physicochemical properties. The present paper describes a comparative study of qualitative and quantitative aspects of road dust samples of four coalfields of India. The pH of the dust was found to be in the range of 5.1-7.7. Moisture, ash, volatile matter, fixed carbon, water-holding capacity, bulk density, and specific gravity of dust samples were found to be in the range of 0.5-3.0%, 45-76%, 12.6-20.0%, 10.2-45.3%, 21.17-31.71%, 1.15-1.70, and 1.73-2.30 g cm(-3), respectively. Observing the overall generation and characteristics of coal dust, it is suggested that coal dust from haul and transport roads of mining areas can be effectively collected and used as domestic fuel.


Assuntos
Poluentes Atmosféricos/análise , Poeira/análise , Poluição do Ar/estatística & dados numéricos , Minas de Carvão/métodos , Minas de Carvão/estatística & dados numéricos , Monitoramento Ambiental , Índia , Veículos Automotores/estatística & dados numéricos
18.
Nepal J Ophthalmol ; 3(2): 206-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21876601

RESUMO

BACKGROUND: A case report of a successful recovery from paraplegia and cortical blindness following anti-venom injection for a snake bite by a common krait is reported here. CASE: A 14-year old male patient was bitten by a common krait. On admission to a tertiary level hospital, he was started with antivenom serum. But the patient developed sudden respiratory distress following anaphylactic shock and he was kept on ventilation. The patient was discharged with paraplegia with loss of vision. He was diagnosed as a case of cortical blindness due to hypoxic ischemic encephalopathy. Subsequently, the patient recovered from paraplegia and regained visual acuity of 6/60 in both eyes (best corrected). The boy was reexamined after four years. CONCLUSION: Evaluation of victims of neurotoxic snake bite for early signs of respiratory depression and prompt respiratory assistance, even if anti-venom is not available, is most essential as a life saving measure.


Assuntos
Cegueira Cortical/etiologia , Bungarus , Encefalite/etiologia , Hipóxia-Isquemia Encefálica/etiologia , Paraplegia/etiologia , Mordeduras de Serpentes/complicações , Adolescente , Animais , Antivenenos/uso terapêutico , Humanos , Masculino , Mordeduras de Serpentes/tratamento farmacológico
19.
J Indian Assoc Pediatr Surg ; 15(3): 108-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21124669

RESUMO

This study reports four children who developed complete stricture of pylorus and antrum of the stomach following accidental ingestion of corrosive agent (toilet cleaner).

20.
Afr J Paediatr Surg ; 7(3): 197-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20859031

RESUMO

Female conjoined twins (thoraco-omphalopagus) were delivered by emergency caesarean section in a private nursing home. On examination, one of the twins was dead and was threatening the survival of the surviving twin (twin A). An emergency separation was performed to salvage the surviving twin.


Assuntos
Gêmeos Unidos/cirurgia , Anormalidades Múltiplas/cirurgia , Emergências , Feminino , Humanos , Recém-Nascido , Resultado do Tratamento
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