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The present work focuses on a detailed inter-comparative assessment of household energy consumption (HEC) patterns for different Indian households including their living style and pattern of using clean energy fuels. This assessment has been done for cooking, heating, cooling, and transportation patterns in different households. It has been observed that the monthly income, family size, and house location have a significant effect on the monthly HEC of a specific household. Besides the complete assessment of HEC, results of the present study also show the potential of solar energy applications through which rural poor households and lower-income households can save approximately $10.77 to $14.36 monthly while urban households can save $17.95 to $29.92 monthly. Rural side medium-income households can save about $10.77 to $14.36 in cooking and about $11.97 to $16.76 monthly in space heating, cooling, and lighting, while urban medium-income households can save about $17.95 to $29.92 monthly. Likely, rural high-income households or rich households can save about $11.97 to $16.76 in cooking, and about $17.95 to $29.92 monthly in space heating, cooling, and lighting while urban high-income households can save about $29.92 to $53.86 monthly. Rich households can save up to $23.94 in cooking, and up to $95.75 monthly in space heating, cooling, and lighting. A complete formulization of the theoretical assessment of HEC has been discussed in this study.
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The present study aimed to explore haplotype structure, runs of homozygosity (ROH), effective population size and persistence of gametic phase among three indigenous dairy cattle breeds, viz., Sahiwal (n = 19), Tharparkar (n = 17), and Gir (n = 16) by using BovineHD single nucleotide polymorphism (SNP) genotyping assay. The filtered SNPs after quality control ranged from 44% in Sahiwal to 53% in Gir. The highest number of haplotype blocks was observed in Tharparkar (15,640) and the lowest in Sahiwal (8027) spanning 17.3% and 7.8% of genome, respectively. The average block length was found close to 26 kb which suggests that multiple recombination events fragmented the ancestral haplotypes into smaller sizes. Gir cattle had the largest number of runs of homozygosity (ROH) regions (1762) followed by Tharparkar (1528) and Sahiwal (1138). Without pedigree information, inbreeding coefficients estimated from ROH (FROH) revealed that Gir had the highest FROH (0.099) proposing more inbreeding rate in this population. Effective population size (Ne) decreased slowly over the last 60 generations and at 13 generations ago; Ne was estimated as 70 for all the three dairy breeds. The highest gametic phase correlation (r = 0.78) was observed for Sahiwal and Tharparkar breed pair suggesting formulation of multi-breed reference population for successful implementation of genomic selection among dairy breeds. The decline in effective population size among native Indian cattle breeds may help in formulating strategies for conservation and genetic improvement of native germplasm for future use.
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Endogamia , Polimorfismo de Nucleótido Simple , Bovinos/genética , Animales , Haplotipos , Densidad de Población , Homocigoto , India , GenotipoRESUMEN
Previous research on solar box cookers focusing on the bulk usage of energy storage materials is a costly technique for performance enhancement. Bulk energy storage materials take much time to charge and, thus, result in a low rate of cooking at the start. Therefore, a hot box solar cooker has been developed and experimentally studied for thermal performance enhancement in a hilly region of Uttarakhand, India. A bed of phase change material (paraffin wax) filled with small capsule-shaped containers was prepared (detachable) and placed over the cooking tray of the tested cooker. These containers were vertically positioned over the bed to enhance the heat transfer rate inside the cooker to attain a fast-cooking response. Notably, the combined effect of extended geometry with PCM is an excellent method to increase the efficiency of a solar cooker. As per the author's knowledge, likely techniques have not been studied for a box cooker to achieve a fast-cooking rate in any hilly region up to date. The results of cooking tests show that the cooking plate attained a maximum temperature of about 150 °C. It is because of the combined effect of extended fins (vertical capsules) and PCM filled inside them. The results of the experimental study show that the thermal efficiency of the cooker was found to be about 45.7%, the cooking power was calculated about 54.71 W, the heat transfer coefficient was estimated about 311 W/m2 °C, and the overall heat loss coefficient was computed about 5.71 W/m2 °C. This modified cooker costs about $48.19, and the payback period is about 03 years and 11 months. Cooking trials also showed that the present SBC could cook almost all the dishes commonly cooked in Uttarakhand.
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Slow and flash pyrolysis of spent citronella biomass has been studied at varying temperatures. It is aimed to understand the pyrolytic behavior of spent citronella aromatic biomass with temperatures. Maximum bio-oil yield of 37.7 wt% was obtained with conversion of 71 wt% at 450 °C through slow pyrolysis. GC/MS, 1H NMR, and FTIR analysis of pyrolytic liquid (bio-oil) was done which indicated various functionalities with maximum area% for phenolics. However, flash pyrolysis at high heating rate of 20 °C/ms resulted into maximum area% for carbonyls at all temperatures. In addition, an increasing trend for phenolics with temperature was also observed. The properties of obtained biochar are analysed by CHNS, FTIR, TOC, XRD, and SEM, which confirmed the significant decomposition of biomass constituents. The characterisation results revealed the potential usage of pyrolytic liquid i.e., bio-oil and pyrolytic residue i.e., biochar for different applications.
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Cymbopogon , Magnoliopsida , Pirólisis , Calor , Biomasa , BiocombustiblesRESUMEN
The rapid transmission of COVID-19 infection around the world in a brief timeframe has caused an exponential decline in street traffic and other industrial activities in various parts of the world. The confined human collaboration with the nature at the time of this emergency has shown up as an advantage for Mother Nature after COVID-19 flare because the air present in the atmosphere and water flowing in river streams is upgrading and untamed life is blossoming. India, being consistently seen as the center of contamination due to a tremendous population, overwhelming road traffic and industries which contribute to heavy pollution prompting rise in air quality index for almost all the big cities of the country. However, after the announcement of lockdown because of COVID-19, the air quality begun to upgrade and other environmental variables, for example, water quality in streams and waterways have begun offering a positive hint towards restoration. This review gives a brief knowledge on the structure and genomic organization of novel coronavirus as well as it focuses on alterations in air and water quality along with its environmental consequences at specific locations of the country during lockdown due to this pandemic circumstance.
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Contaminantes Atmosféricos , COVID-19 , Contaminantes Atmosféricos/análisis , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , India/epidemiología , Pandemias , Material Particulado/análisis , SARS-CoV-2RESUMEN
Oxidative depolymerization of an industrial lignin was performed to study the effect of various metal oxides in oxygen and air atmosphere. CeO2 exhibited excellent catalytic property, and promoted the production of bio-oil yield up to a maximum of 49 wt% in 10 bar O2, whereas 31 wt% bio-oil was noticed in atmospheric air. GC-MS analysis of bio-oil showed that high selectivity towards acetosyringone was observed in the presence of air (70.5 area%) as compared to oxygen (48.1 area%). Herein, we have also applied transitional metals (Co, Mn and Cu) doped CeO2 catalysts. Compared to Cu and Mn, Co metal showed efficient activity that promoted the breaking of labile ß-O-4 linkages via the conversion of Cα-OH in to carbonyl group in atmospheric air resulting in the formation of acetosyringone up to 78 area%. Moreover, it exhibited excellent catalytic activity up to four successive cycles. Catalyst has been characterized by XRD, BET, TEM, FT-IR and Raman spectroscopy.
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Lignina , Óxidos , Catálisis , Lignina/química , Estrés Oxidativo , Óxidos/química , Oxígeno , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this study, lignin-derived zeolite templated carbon materials were fabricated to remove the organic contaminant, methyl orange. Response surface methodology with Box-Behnken design was used to optimize the adsorption parameters. Based on Box-Behnken design, a quadratic model was developed to correlate the adsorption variables with the response, removal efficiency. Analysis of variance revealed the adsorbent dosage as the most influential adsorption variable. Lignin derived ZSM-5 (PZ) and mordenite (PM) templated carbon materials exhibited high surface area; 476.0 and 716.0 m2/g respectively. The maximum theoretical adsorption capacity of PZ and PM for methyl orange was 514.0 and 225.0 mg/g, respectively. The experimental kinetic data best fitted to pseudo-second-order model for both the adsorbents. PZ adsorbent was also utilized to treat real wastewater containing dyes and achieved 40 % methyl orange removal efficiency. Adsorption thermodynamic study revealed the process as spontaneous, exothermic and also indicated the increment in entropy after adsorption.
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Carbono , Contaminantes Químicos del Agua , Adsorción , Compuestos Azo , Concentración de Iones de Hidrógeno , Cinética , Lignina , Termodinámica , Contaminantes Químicos del Agua/análisisRESUMEN
Lignin is a waste by-product of bio-refineries and paper-pulp industries. It has an attractive potential to produce numerous valuable chemicals due to its highly aromatic character. At present, large amount of lignin is burnt as a source of energy due to lack of suitable efficient lignin valorisation processes. The challenge exists in handling its complex heterogeneous structure and bond breaking at selective locations. The production of high value chemicals/petrochemical feedstocks will improve the economic viability of a bio-refinery. Oxidative depolymerization is a promising way to produce functional compounds from lignin. The aim of the current review is to present the novel methodologies currently used in the area of lignin oxidative depolymerization including effect of temperature, residence time, solvent, oxidizing agents, homogeneous and heterogeneous catalysis etc. It aims to present an insight into the structure of lignin and its breakdown mechanism.
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Lignina , Estrés Oxidativo , Catálisis , Oxidación-Reducción , SolventesRESUMEN
The aromatic nature of lignin makes it a good source for the production of numerous platform chemicals. The valorization of lignin into valuable compounds depends upon the type of bonds and functionality present in lignin. Here, we have studied the depolymerization of rice straw alkali lignin in N2 and O2 with acidic (ZSM-5), basic (MgO) catalyst and with their mixtures (1:1, 3:7 and 7:3). The effect of hydrogen peroxide on lignin depolymerization was also examined. Maximum yield of bio-oil (50 wt%) was obtained with pure ZSM-5 and 1 ml hydrogen peroxide in nitrogen atmosphere, while maximum conversion (60%) was observed in oxygen environment during the non-catalytic depolymerization of lignin. Bio-oil characterization through GC-MS showed maximum selectivity towards 2-methoxy-4-vinylphenol with 38.5 area% in the bio-oil of ZSM-5-N2. The bio-oils have also been characterized using 1H NMR, FT-IR and GC-MS.
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Álcalis , Lignina , Catálisis , Estrés Oxidativo , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Carbon-based support catalysts are beneficial on account of low material cost, prominent surface area, and stability at high temperature. In this study, biochar derived activated carbon (AC) supported metal catalysts were tested for hydrothermal liquefaction (HTL) of alkali lignin. Catalytic HTL of alkali lignin was carried out at various temperatures (260 to 300 °C) with varying catalysts quantity (5 to 20 wt%), and solvents (water, ethanol, methanol) for 15 min reaction time. As the reaction temperature increased from 260 to 300 °C, conversion increased from 76.2 to 85.5 wt%. Bimetallic catalyst Ni-Co/AC with ethanol solvent system at 280 °C gave highest bio-oil yield (72.0 wt%). Lignin catalytic depolymerization produces monomer phenolic compounds due to efficient breaking of the lignin macromolecule. Thus, the presence of catalyst and solvent increased the cleavage of ß-O-4 bonds resulting in increased selectivity towards vanillin (32.3-36.2%).
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Álcalis , Lignina , Catálisis , Carbón Orgánico , Temperatura , AguaRESUMEN
BACKGROUND: Depression is a disorder of the brain, a state of low mood and aversion to activity that can affect a person's thoughts, behavior, feelings, and sense of well-being and can cause alteration in sympathetic activity of the body, thus affecting heart rate variability (HRV). AIM: The study was conducted to determine the effects of depression on HRV parameters in clinically known cases of depression. MATERIALS AND METHODS: A cross-sectional (observational) study was conducted on fifty known patients of depression, aged 18-65 years, and fifty healthy, age-matched, normal controls. HRV test was conducted, and the results were analyzed statistically using Student's "t"-test for equal variance, for various parameters. RESULTS: The study showed that the differences in mean R-R interval(s), mean HR (beats/min), very low frequency (VLF) power (milliseconds squared [ms2]), and low frequency/high frequency (LF/HF) power (%) (LF/HF ratio) among controls and cases were statistically highly significant, while the differences in LF power (ms2) in controls and cases were statistically significant. However, the differences in basic anthropometric parameters, STD (standard deviation of the normal to normal)(s), root mean square successive difference (ms), NN50 (count), pNN50 (%), VLF peak (Hz), LF peak (Hz), HF peak (Hz), HF power (ms2), VLF power (%), LF power (%), HF power (%), LF power (nu), and HF power (nu) were found to be statistically insignificant. CONCLUSION: Depression leads to changes in autonomic control of the body and changes the autonomic balance in favor of an increased sympathetic tone, which can be detected with fair accuracy with HRV analysis.
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OBJECTIVE: Evaluate change in functional performance from 1- to 5-years after anterior cruciate ligament reconstruction (ACLR). METHODS: 59 participants (38 men) aged 29 ± 16 years completed three hops and one-leg rise 1- and 5-years following ACLR. Linear mixed-effects models evaluated differences in change between the ACLR and contralateral limbs. Participants were classified with stable, improving or worsening function relative to previously published minimal detectable change thresholds. Healthy controls completed the three hops (n = 41) and one-leg rise (n = 31) as reference data. RESULTS: The contralateral limb had a significantly greater decrease in functional performance between 1- and 5-years for the three hops, compared to the ACLR limb. Worsening was more common in the contralateral limb than the ACLR limb; resulting in significant improvements in the LSI for the single hop (mean 87% at 1-year to 95% at 5-years), side hop (77%to 86%) and one-leg rise (76% to85%). Performance of both ACLR and contralateral limbs and the LSI remained below the healthy controls. CONCLUSION: Functional performance changes differ between limbs between 1- and 5-years post-ACLR. The LSI should not be used in isolation to evaluate functional performance changes after ACLR, as it may overestimate functional improvement, due to worsening contralateral limb function.
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Lesiones del Ligamento Cruzado Anterior/fisiopatología , Reconstrucción del Ligamento Cruzado Anterior/métodos , Extremidad Inferior/fisiopatología , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/diagnóstico , Lesiones del Ligamento Cruzado Anterior/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Factores de Tiempo , Adulto JovenRESUMEN
The hydrothermal liquefaction (HTL) of Sargassum tenerrimum (ST) macroalgae was carried out for 15 min, over various solid base catalysts (CaO supported on CeO2, Al2O3, and ZrO2) at different reaction temperatures (260-300 °C), different catalyst quantities (5-25 wt%) and using different solvent systems. Maximum bio-oil (BO) yields for the non-catalytic HTL with single solvent water, ethanol, and water-ethanol co-solvent were 3.3 wt%, 23.3 wt%, and 32.0 wt%, respectively, at 280 °C. Ethanol as single solvent elicited highest BO yield of 25.2 wt% with CaO/ZrO2 (10.0 wt%) catalyst. However, the highest BO yield (33.0 wt%) accompanied by higher conversion (70.5%) was obtained with CaO/ZrO2 (10.0 wt%) under water-ethanol co-solvent. The selectively higher percentage of ester functional compounds (87.8%) was found with CaO/ZrO2 catalyst under water-ethanol co-solvent. Also, the bio-oil obtained from catalytic liquefaction showed a higher high heating value (HHV) compared to that from the non-catalytic HTL reaction.
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Algas Marinas , Biocombustibles , Catálisis , Solventes , Temperatura , AguaRESUMEN
Effective management and the valorization of agro-industrial lignocellulosic feedstocks can only be realized if a versatile cellulase cocktail is developed that can release glucose at affordable cost irrespective of biomass type. In the present study the flexibility of using cellulase cocktail obtained from mutant UV-8 of Talaromyces verruculosus IIPC 324 in depolymerizing multiple agro-industrial lignocellulosic feedstocks was explored. Five different dilute acid pretreated biomasses were evaluated and cellulase loading was done at 25 mg protein/g cellulose content. After 72 h of hydrolysis at 55 °C and pH 4.5, corn cob and rice straw emerged as the easiest and toughest substrates with saccharification yield of 83.9 ± 1.17 and 35.5 ± 1.16% respectively from their cellulose fraction. Addition of PEG 6000 could retain >65% of all mono-component enzymes present in cellulase cocktail. Structural elucidation of biomasses gave an insight about key features responsible for variable recalcitrance in the different agro-industrial feedstock. Cellulose hydrolysis showed a significant negative correlation in the order of Cr I > S/G ratio > ash content. The chemical composition of lignin had a major impact on enzyme-lignin interactions. Higher H lignin content and lower S/G ratio promoted enzyme desorption, thereby increasing the likelihood of their recycling and reuse.
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Celulasa/genética , Celulasa/metabolismo , Lignina/química , Lignina/metabolismo , Mutación , Polimerizacion , Talaromyces/enzimología , Agricultura , Hidrólisis , IndustriasRESUMEN
The production of phenolics by oxidative depolymerization of prot lignin and alkali lignin were studied in the presence of cobalt impregnated TiO2, CeO2 and ZrO2 catalysts at 140 °C for 1 h. Maximum bio-oil yield of 78.0 and 60.2 wt% were observed with Co/CeO2 catalyst for prot lignin and alkali lignin, respectively. The characterizations of the bio-oils were carried out using GC-MS, FTIR, and 1H NMR. The GC-MS compounds have been classified into four categories (G, H, S-type and others). The depolymerization of prot lignin showed a mixture of G, H and S type phenolic monomers. Interestingly, higher selectivity of acetosyringone (47.1%) was obtained in the presence of Co/TiO2 catalyst with prot lignin. The depolymerization of alkali lignin exhibited only G-type phenolic monomers production, and was effectively produced 67.4% (G-type monomer) in the presence of Co/ZrO2 catalyst.
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Cobalto , Lignina , Álcalis , Catálisis , Estrés Oxidativo , Óxidos , Titanio , CirconioRESUMEN
Catalytic fast pyrolysis of soda lignin was examined at different temperatures (500,600,700,800 and 900⯰C) in the presence of three zeolites with different Si/Al ratio using the Py-GC/MS in order to investigate best catalytic system. The three zeolites are y-zeolite (8-9), mordenite (15-17), ZSM-5 (30-40), which have static pore sizes 0.74, 0.65, and 0.59â¯nm respectively. The shape and acidity of zeolites, as well as pyrolysis temperature, have a significant effect on product distribution in catalytic fast pyrolysis. Y-zeolite was the most effective catalytic system among all catalysts for deomethoxylation and dehydroxylation of small oxygenates as well as bulky oxygenates to produce aromatics. However, mordenite and ZSM-5 could not convert the large oxygenates due to size exclusion and pore blockage. Highest yield of aromatics with significant amount of aromatic dimers was obtained over y-zeolite and then yield of aromatics followed in order by mordenite and ZSM-5 at 800⯰C.
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Lignina/química , Zeolitas/química , Catálisis , Cromatografía de Gases y Espectrometría de Masas , Calor , PirólisisRESUMEN
BACKGROUND: Non-small-cell lung cancer (NSCLC) patients often demonstrate varying clinical courses and outcomes, even within the same tumor stage. This study explores deep learning applications in medical imaging allowing for the automated quantification of radiographic characteristics and potentially improving patient stratification. METHODS AND FINDINGS: We performed an integrative analysis on 7 independent datasets across 5 institutions totaling 1,194 NSCLC patients (age median = 68.3 years [range 32.5-93.3], survival median = 1.7 years [range 0.0-11.7]). Using external validation in computed tomography (CT) data, we identified prognostic signatures using a 3D convolutional neural network (CNN) for patients treated with radiotherapy (n = 771, age median = 68.0 years [range 32.5-93.3], survival median = 1.3 years [range 0.0-11.7]). We then employed a transfer learning approach to achieve the same for surgery patients (n = 391, age median = 69.1 years [range 37.2-88.0], survival median = 3.1 years [range 0.0-8.8]). We found that the CNN predictions were significantly associated with 2-year overall survival from the start of respective treatment for radiotherapy (area under the receiver operating characteristic curve [AUC] = 0.70 [95% CI 0.63-0.78], p < 0.001) and surgery (AUC = 0.71 [95% CI 0.60-0.82], p < 0.001) patients. The CNN was also able to significantly stratify patients into low and high mortality risk groups in both the radiotherapy (p < 0.001) and surgery (p = 0.03) datasets. Additionally, the CNN was found to significantly outperform random forest models built on clinical parameters-including age, sex, and tumor node metastasis stage-as well as demonstrate high robustness against test-retest (intraclass correlation coefficient = 0.91) and inter-reader (Spearman's rank-order correlation = 0.88) variations. To gain a better understanding of the characteristics captured by the CNN, we identified regions with the most contribution towards predictions and highlighted the importance of tumor-surrounding tissue in patient stratification. We also present preliminary findings on the biological basis of the captured phenotypes as being linked to cell cycle and transcriptional processes. Limitations include the retrospective nature of this study as well as the opaque black box nature of deep learning networks. CONCLUSIONS: Our results provide evidence that deep learning networks may be used for mortality risk stratification based on standard-of-care CT images from NSCLC patients. This evidence motivates future research into better deciphering the clinical and biological basis of deep learning networks as well as validation in prospective data.
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Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Aprendizaje Profundo , Diagnóstico por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Toma de Decisiones Clínicas , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Datos Preliminares , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Factores de RiesgoRESUMEN
An unprecedented copper mediated one-pot sequential synthesis of 1,2,3-triazolo cinnolinone derivatives from 2-halo-phenyl triazoles and terminal alkynes has been reported. Under the optimized reaction conditions, a broad range of substituted triazoles and alkynes were found to participate in this transformation, thus affording unknown 1,2,3-triazolo cinnolinone derivatives in moderate to excellent yields. This method proceeds through sequential C-C coupling followed by an annulation cascade sequence in the same vessel under atmospheric air as the sole oxidant, thus representing a simple, efficient and atom economical approach for the synthesis of aza-cinnolinones.
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BACKGROUND: Nerve conduction studies (NCSs) are essential for diagnosing various kinds of focal and diffuse neuropathies. Due to the paucity of local NCS data, electrodiagnostic laboratories in Punjab rely on values from Western and other Indian studies. AIM: This study was conducted to provide normative data for median nerve conduction parameters (motor and sensory) in Punjabi populace. MATERIALS AND METHODS: A cross-sectional study was done on 290 participants (150 males and 140 females), aged 17-21 years, as per standardized protocol. The data were analyzed separately for both genders using SPSS version 20. It consisted of distal latencies and conduction velocities of motor and sensory divisions of median nerve. Student's unpaired t-test was used for statistical analysis. RESULTS: There was no effect of gender on any of the median nerve conduction parameters. Height and weight had nonsignificant negative and positive correlation, respectively (P > 0.05), with conduction velocity in both motor and sensory median nerves. For median motor nerve, the values of distal latency and conduction velocity in males were 2.9 ± 0.16 ms and 60.25 ± 2.99 m/s, respectively, whereas, in females, they were 2.6 ± 0.43 ms and 59.83 ± 2.82 m/s. Similarly, for median sensory nerve, the latency and velocity values in males were 2.8 ± 0.56 ms and 54.81 ± 3.70 m/s, whereas, in females, they were 2.4 ± 0.33 ms and 54.56 ± 3.65 m/s, respectively. CONCLUSION: The data in this study compared favorably with already existing data. It would help the local electrodiagnostic laboratories in assessing the median nerve abnormalities with greater accuracy in this population subset.
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BACKGROUND: Brick manufacturing industry is one of the oldest and fast-growing industries in India that employs a large section of people. Brick kiln workers are occupationally exposed to air pollutants. Nonetheless, only a few studies have so far been conducted on their respiratory health. OBJECTIVE: To investigate the extent of respiratory impairment in brick kiln workers and to correlate it with the duration of exposure. METHODS: A cross-sectional study was conducted. Spirometric parameters of 110 non-smoking male brick kiln workers aged 18-35 years in Patiala district, Punjab, India, were compared with an age-matched comparison group of 90 unexposed individuals. RESULTS: Brick kiln workers showed a significant (p<0.05) decline in forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), forced mid-expiratory flow rate (FEF25-75%) and peak expiratory flow rate (PEFR) compared with those of the comparison group. The extent of deterioration in lung function of brick kiln workers was associated with the duration of exposure. In workers with >8 years of exposure, the mean values of FEV1 (1.92 L), FVC (2.01 L), FEF25-75% (2.19 L/s) and PEFR (4.81 L/s) were significantly (p<0.05) lower than those recorded in workers with <8 years of exposure in whom the values were 2.01 L, 2.68 L, 2.71 L/s, and 5.76 L/s, respectively. CONCLUSION: There is a significant association between exposure to workplace pollutants and lung function deterioration among brick kiln workers.