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1.
Environ Geochem Health ; 45(10): 6955-6965, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36725791

RESUMO

Additives provide substantial improvement in the properties of composites. Although bio-based composites are preferred over synthetic polymer and metal-based composites, they do not have the requisite properties to meet specific needs. Hence, organic, inorganic and metallic additives are included to improve the properties of bio-based composites. Coal is a readily available resource with high thermal insulation, flame resistance and other properties. This work demonstrates the addition of 20-30% natural sub-bituminous coal as filler for coir-reinforced polypropylene (PP) composites and exhibits an increased tensile strength by 66% and flexural strength by 55% compared to the composites without any filler. Such composites are intended for insulation applications and as a replacement for gypsum-based false ceiling tiles. Various ratios of coal samples were included in the composites and their effect on mechanical, acoustic, thermal insulation, flame and water resistance have been determined. A substantial improvement in both flexural and tensile properties has been observed due to the addition of coal. However, a marginal improvement has been observed in both thermal conductivity (0.65 W/mK) and flame resistance values due to the presence of coal. Adding coal increases the intensity of noise absorption, particularly at a higher frequency, whereas water sorption of the composites tends to decrease with an increase in the coal content. The addition of coal improves and adds unique properties to composites, allowing coir-coal-PP composites to outperform commercially available gypsum-based insulation panels.


Assuntos
Retardadores de Chama , Polipropilenos , Sulfato de Cálcio , Carvão Mineral , Água
2.
Environ Geochem Health ; 45(8): 6471-6493, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326777

RESUMO

The geochemistry of fly ash produced from the combustion of coal at thermal power plants presents a significant challenge for disposal and environmental impact due to its complex mineralogical and elemental composition. The objective of this study was to investigate the mineralogical and elemental distribution of thirty lignite samples from the Barmer Basin using advanced techniques such as X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). XRD analysis revealed the presence of minerals such as haematite (Fe2O3), nepheline, anhydrite, magnesite, andalusite, spinel and anatase. Other minor minerals included albite, siderite, periclase, calcite, mayenite, hauyne, pyrite, cristobalite, quartz, nosean and kaolinite. XRF analysis demonstrated that the most abundant elements in the Barmer Basin lignite ash were iron oxide (Fe2O3), sulphur oxide (SO3), calcium oxide (CaO), and quartz (SiO2) followed by minor traces of toxic oxides (SrO, V2O5, NiO, Cr2O3, Co2O3, CuO) that are known to have adverse effects on human health and the environment. The rare earth element (REE) composition showed higher concentrations of Tb, Dy, Ho, Er, Tm, Yb, Lu, Y and Sc at the Giral and lower concentrations at Sonari mine. The Barmer lignites recorded higher concentration of trace elements such as V, Cr, Co, Ni, Cu and Sr while lower concentration of Rb, Cs, Ba, Pb, As, Th and U were observed within optimal range. The study findings revealed the predominant mineral concentration, elemental makeup, trace elements and rare earth elements associated with lignite reserves in the Barmer Basin.


Assuntos
Metais Terras Raras , Oligoelementos , Humanos , Oligoelementos/análise , Carvão Mineral/análise , Dióxido de Silício/análise , Quartzo/análise , Índia , Minerais/análise , Metais Terras Raras/análise
3.
Environ Res ; 204(Pt D): 112382, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34793761

RESUMO

In coal, total sulphur content is not the only important factor for the industry, but also the forms of sulphur and their distributions should be considered before utilizing any coal for a particular use. In Jharia and Raniganj coalfields, sulphur is present in the forms of organic sulphur (OS), pyritic sulphur (PS), and sulphate sulphur (SS). In this perspective, the present study aims to know the different forms of sulphur in coking and non-coking coals of Jharia and Raniganj coalfields. Twenty samples were collected from both the mining areas. The total sulphur content in coking coals varied from 0.28% to 0.55% and in non-coking coals it varied from 0.33% to 0.54%. The distribution pattern of sulphur showed that PS and OS are dominating in both the coalfields. The OS in Jharia field varied from 0.13% to 0.47%, and in Raniganj coalfield it varied from 0.19% to 0.41%. This depicts that both the coalfields were formed under freshwater condition. Similarly, PS varied from 0.01% to 0.21% and from 0.06% to 0.29%, and SS varied from 0.0052% to 0.01% and 0.005%-0.02% in the above fields, respectively. It is noticed that the content of sulphate sulphur is less than 0.1 wt%, which is lower than other forms of sulphur. In the past two decades, sulphur emission has increased with the increase of thermal power plants due to more demand for power, which is one of the causes of global warming. During coal combustion, H2S and SOx, are produced and that can react with O2 and H2O to form H2SO3, H2SO4 or H2S. Thus, sulphur release can respond within the ecosystem in the form of acidic precipitation that may acidify and affect lakes and streams, sub-surface water and historical monuments. In India, coal consumption and ecological contaminations are increasing day by day due to the rapid energy consumption. Therefore, special attention should be given to adopt clean coal technologies though the coal contains less sulphur.


Assuntos
Carvão Mineral , Ecossistema , Fracionamento Químico , Carvão Mineral/análise , Monitoramento Ambiental , Centrais Elétricas , Enxofre
5.
J Orthop ; 47: 148-150, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38425494

RESUMO

The Journal of Orthopaedics is one of the leading and fast-growing Orthopaedic journals from Asia (and India). It has demonstrated an increase in all the important journal metrics like submissions, citations, h-index, and Cite Score and has achieved its first journal impact factor in 2022.

6.
J Orthop ; 42: 45-46, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37483645

RESUMO

The Journal of Orthopaedics (JOO) has proudly received its first Journal Impact Factor of 1.5, recently. It is the highest ranked journal in the field of Orthopaedics and Sports Medicine from India and is ranked at 9th amongst all Asiatic countries. It has a wide international authorship, and readership, with a diverse editorial board. All the important journal metrics of the JOO have shown an upward trend.

7.
J Orthop ; 35: 155-159, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36818164

RESUMO

The Journal of Orthopaedics has progressed quite well in 2022, with all the major journal metrics (like h-index, cite score, citations, rankings etc) having gone up. It has truly become an international journal, with maximum authorship from the USA and UK. It is now ranked at number one amongst all the Indian orthopaedic journals and is ranked 6th amongst Asiatic orthopaedic journals.

8.
Chemosphere ; 338: 139471, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37442395

RESUMO

The Sampar Coalfield in Northeastern India is a source of plentiful coal reserves, which are burnt for energy production and industrial applications, resulting in the release of pollutants such as sulphur , arsenic, and lead, which are hazardous to the environment and public health. In this work, samples from the Sampar coalfield have been analyzed to understand the origin, distribution, and various forms of sulphur and their ability to detect toxic heavy metals. The total sulphur concentration ranged from 4.31% to 6%, with organic sulphur being the predominant form at 69.21%, followed by pyritic sulphur at 16.49% and sulphate sulphur at 14.28%. With high sulphur content, this coal indicates a marine influence in the peat-forming swamps. The samples have also been examined for petrographic and elemental analysis, which have revealed the presence of vitrinite, liptinite, inertinite, carbon, hydrogen, nitrogen, oxygen, and mineral matter. In addition, the same coal sample has also been used for electrochemical sensing-based detection of toxic heavy metals like arsenic and lead, and the findings indicate an improved efficacy. These results are expected to have significant implications in the development of effective bio-based remediation strategies in the region to mitigate the harmful effects of coal-related pollution.


Assuntos
Arsênio , Recuperação e Remediação Ambiental , Metais Pesados , Carvão Mineral/análise , Arsênio/análise , Metais Pesados/análise , Enxofre
9.
Chemosphere ; 307(Pt 1): 135710, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35842041

RESUMO

Coal and coal-based products (by-products), along with other fossil fuels should be used with caution because of their impact on human health and the global climate. In the light of the environmental impact these fossil fuels cause, it's essential to understand the elemental configuration of coal-derived samples and their impact on the ecosystem. Some reports in past have described, geochemical and mineralogical physiognomies of fly-ash and their impact on the environment. However, a comprehensive investigation of various aspects of fly ash like geochemistry, mineralogy, morphology, and toxicological effects has been very sparse and the present study reports the above aspects. The ICP-OES studies confirm the presence of various elements (Al, Ca, Fe, Mg, Na, P, S, Si, and Ti) in the samples. The XRD analysis exposed the presence of minerals like Quartz, H-Hematite, Anatase, Muscovite, and Rutile, in addition to the various phases such as amorphous and crystalline in the fly-ash. Specific samples also possessed Ilmenite which is uncommon in many other samples. Chromium and lead, the well-known heavy metals to cause soil and water pollution in the neighbourhood were found to be existing in higher concentrations in the fly-ash samples, whereas cadmium was found to be the least among the toxic elements found in the samples. The samples were subjected to FE-SEM analysis, which reveals the presence of irregularly shaped minerals and unburnt carbon known to reduce the burning efficiency of coal, especially in power plants. Toxicology studies reported in the work suggested that fly-ash is toxic to the environment at higher concentrations than at lower concentrations.


Assuntos
Cinza de Carvão , Metais Pesados , Cádmio/análise , Carbono , Cromo/análise , Carvão Mineral/análise , Cinza de Carvão/química , Ecossistema , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Minerais , Centrais Elétricas , Quartzo , Solo/química
10.
Indian J Orthop ; 55(2): 342-351, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33927812

RESUMO

AIM: Infection after anterior cruciate ligament (ACL) reconstruction, though rare, is a potentially devastating complication and the evidence-based recommendation on the various topics in its management is limited. The purpose of this study was to develop recommendations for the prevention and management of infections in ACL reconstruction surgery by performing a structured expert consensus survey using Delphi methodology. MATERIALS AND METHODS: 22 topics of relevance in the prevention and management of infection following ACL reconstruction were chosen from an extensive literature review. 30 panelists were requested to respond to a three-round survey, with feedback, to develop a consensus statement on the topics. RESULTS: Consensus statements could be prepared in eleven out of twenty-two topics including: the graft is retained at the first arthroscopic debridement, the graft is removed when repeated debridement are needed, and revision ACL reconstruction is needed only if the patient develops instability. Concurrence could be obtained in the topics including: longer duration of antibiotics is needed in immunocompromised patients, soaking graft in antibiotic solution reduces infection risk, and knee swelling without warmth does not suggest infection. CONCLUSIONS: A proper skin preparation, a longer course of antibiotics in immunocompromised patients, and soaking the graft in antibiotics reduces the risk of infection. In case of infection, a healthy-looking graft must be retained at the first debridement and if the graft must be removed, revision ACL reconstruction is advised only if the patient develops instability. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43465-021-00363-z.

11.
J Bone Joint Surg Br ; 88(12): 1660-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17159184

RESUMO

We stably transfected early passage chondrocytes with an anti-apoptotic Bcl-2 gene in vitro using a retrovirus vector. Samples of articular cartilage were obtained from 11 patients with a mean age of 69 years (61 to 75) who were undergoing total knee replacement for osteoarthritis. The Bcl-2-gene-transfected chondrocytes were compared with non-transfected and lac-Z-gene-transfected chondrocytes, both of which were used as controls. All three groups of cultured chondrocytes were incubated with nitric oxide (NO) for ten days. Using the Trypan Blue exclusion assay, an enzyme-linked immunosorbent assay and flow cytometric analysis, we found that the number of apoptotic chondrocytes was significantly higher in the non-transfected and lac-Z-transfected groups than in the Bcl-2-transfected group (p < 0.05). The Bcl-2-transfected chondrocytes were protected from NO-induced impairment of proteoglycan synthesis. We conclude that NO-induced chondrocyte death involves a mechanism which appears to be subject to regulation by an anti-apoptotic Bcl-2 gene. Therefore, Bcl-2 gene therapy may prove to be of therapeutic value in protecting human articular chondrocytes.


Assuntos
Apoptose/genética , Cartilagem Articular/citologia , Condrócitos/efeitos dos fármacos , Genes bcl-2 , Óxido Nítrico/farmacologia , Idoso , Apoptose/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/citologia , Condrócitos/fisiologia , Fragmentação do DNA , Feminino , Vetores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Proteoglicanas/biossíntese , Retroviridae/genética , Transfecção/métodos
13.
Mil Med ; 164(11): 814-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10578595

RESUMO

The efficacy of a composite Indian herbal preparation (CIHP) in sustaining the mental performance of soldiers engaged in prolonged low-intensity-conflict operations has been evaluated. For this purpose, a cohort of 56 soldiers acted as volunteers in combat situations. After recording their initial responses to psychological tests such as the d2 test, the trail-making test, the serial addition test, the short-term memory test, and the Institute for Personality and Ability Testing Anxiety Scale, they were randomly given either CIHP or placebo in a double-blind fashion for 8 days while they performed their usual combat duties. The final 3 days of assignments included physically exhausting and life-threatening events. On day 8, they were withdrawn from combat duties and the psychological tests were readministered immediately. After 7 days of rest, the tests were repeated once again. The results indicate comparatively better performance immediately after the mission by the CIHP group. CIHP was effective at sustaining the mental abilities of soldiers in a low-intensity-conflict environment.


Assuntos
Militares , Fitoterapia , Adulto , Método Duplo-Cego , Humanos , Índia , Masculino , Processos Mentais/efeitos dos fármacos , Testes Psicológicos , Guerra
14.
Arch Environ Health ; 43(1): 15-7, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3355239

RESUMO

Variation in mental performance under different levels of heat stress-induced dehydration was recorded in 11 subjects heat acclimatized to the tropicals. Dehydration was induced by a combination of water restriction and exercise in heat. The psychological functions--arithmetic ability, short-term memory, and visuomotor tracking--were assessed in a thermoneutral room after the subjects recovered fully from the effects of exercise in heat, as reflected by their oral temperature and heart rate. The results indicated significant deterioration in mental functions at 2% or more body dehydration levels.


Assuntos
Desidratação/fisiopatologia , Temperatura Alta/efeitos adversos , Processos Mentais , Estresse Fisiológico/complicações , Adulto , Desidratação/etiologia , Humanos , Inteligência , Masculino , Memória de Curto Prazo , Teste de Sequência Alfanumérica
16.
J Orthop ; 15(1): A1-A2, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29657483
17.
J Orthop ; 12(3): 123-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26236113
18.
J Orthop ; 12(2): 63-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25972705
19.
Saudi J Gastroenterol ; 16(3): 218-20, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20616420

RESUMO

In recent years, the synchronous occurrence of tumors of different histotypes arising in the same organ has been reported more frequently in the literature. In the stomach, adenocarcinoma has been described with coexisting primary rhabdomyosarcoma, carcinoid, and low-grade B-cell lymphoma of mucosa-associated lymphoid tissue. The simultaneous development of adenocarcinoma and gastric mesenchymal tumor has been documented rarely. We report one such case. A 65-year-old male was diagnosed with a proximal gastric adenocarcinoma and underwent subtotal gastrectomy. Subsequent histopathological examination revealed the presence of another tumor at the gastric antrum. This was a gastrointestinal stromal tumor of low risk category (GIST). The literature has only a few previous reports of this very rare association. It is not known whether this synchronicity is incidental or there is a causative factor inducing the development of tumors of different histotypes in the same organ. Pathologists, oncologists and surgeons should be aware of this interesting condition.


Assuntos
Adenocarcinoma/patologia , Tumores do Estroma Gastrointestinal/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/cirurgia , Idoso , Gastrectomia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Masculino , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Gástricas/cirurgia
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