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1.
J Environ Manage ; 358: 120915, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38640753

RESUMO

The demand for paper and paper-based packaging has seen a massive increase in past years, resulting in accelerated deforestation to meet the rising demand, negatively impacting the environment, and there is a need to look towards different non-woody raw materials. Kraft pulping (KP) is widely used in paper making, for which the chemical dose, temperature, time, and energy required must be optimized, for which many insignificant experimental trials are performed. An effort is made to solve this problem by developing the regression equations with the help of Excel using One Factor at a Time Analysis (OFAT), followed by carrying out design of experiments (DoE) using orthogonal approach and regression analysis in Minitab software. Life cycle Assessment (LCA) using the Open-LCA software estimates the effect of chemicals and energy required during pulping on human health, ecosystem quality, and resource depletion. Using regression analysis, the equations for predicting kappa number, yield (%), total energy consumed, and mechanical properties of the paper sheet showed a good fit with an R2 value in the range of 0.90-0.99. Apart from that, the mechanical properties, namely tensile index (41.43 Nm/g), tear index (6.96 mN m2/g), bending stiffness (0.5 mN m), and burst index (3.92 kPa m2/g) of the unbeaten sheet, were determined experimentally at optimized conditions. Based on the Open-LCA result, the optimized pulping conditions had less impact on human health, ecosystem quality, and resource depletion. Industries can use the model to predict the values of kappa number, yield, mechanical properties, and energy consumption without performing optimization experiments that may impact the industry's economy to a greater extent.


Assuntos
Papel , Triticum , Análise de Regressão , Conservação dos Recursos Naturais
2.
Sci Rep ; 13(1): 6426, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081061

RESUMO

Paper and packaging materials a lignocellulose-based natural biodegradable polymer that spontaneously releases acetic acid, aldehydes, alcohol, and ester-based volatile organic compounds (VOCs) upon ageing and these VOCs start degrading the paper products and decline their mechanical strength properties. The reactivity of the paper of unbleached wheat straw pulp towards acetic acid and hexanal, which has been proven to have more degrading effects on paper than other VOCs, was considered in this work. The papers were exposed to these volatile compounds for 90 days in an air-tight vessel under ambient environmental conditions. The results showed that hexanal was more destructive than acetic acid with regards to cellulose degradation and depletion in the mechanical strength properties. The paper properties like, tensile, tear and burst index, viscosity, pH and carbonyl group content was measured. The growth of the carbonyl group, evidence of the ageing effects in the paper, detected more in the paper exposed to acetic acid. However, the strength of paper properties declined more with hexanal. FE-SEM analysis of the sample showed the development of pores and damage of cellulose fibre upon ageing. Similarly, the damaging effects of VOCs on cellulose, hemicelluloses and lignin were confirmed by significantly reduced peak detection through FT-IR \analysis. The high crystallinity index of the paper products due to exposure to VOCs was detected by XRD analysis, which confirmed the degradation of the low molecular weight cellulose molecule. Thus, the results are strongly recommended that VOCs that generates due to natural or artificial ageing could be the leading cause of paper degradation.

3.
SN Compr Clin Med ; 2(10): 1761-1766, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32864572

RESUMO

Corona virus disease (COVID-19), caused by SARS-CoV-2, is rapidly spreading all around the world and is posing a threat to mankind. Since SARS-CoV-2 is a novel virus, little is known about it and no effective drug is available for its treatment. While many drugs are being evaluated, an effective therapeutic measure is still lacking. SARS-CoV-2 like SARS-CoV binds with angiotensin-converting enzyme 2 (ACE2) present on human cells. SARS-CoV has been found to downregulate ACE2 and SARS- CoV-2 infection has been found to be associated with increased level of Angiotensin II. Based on these facts, we presume that SARS-CoV-2 like SARS-CoV downregulates ACE2, and in absence/reduced activity of ACE2, level of angiotensin (1-7) and angiotensin (1-9) is decreased while that of angiotensin II is increased and increased level of angiotensin II has been found to correlate with lung injury and viral load. We presume that restoration of normal functioning of renin-angiotensin system with recombinant human angiotensin-converting enzyme 2 (rhACE2), angiotensin (1-7) and angiotensin (1-9) may be an effective therapeutic measure but studies will be required to test this hypothesis and explore its possible role in treatment of COVID-19.

4.
Indian J Surg Oncol ; 9(3): 398-401, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30288006

RESUMO

Carcinosarcoma, a tumor having both carcinomatous and sarcomatous elements, occurring in the breast, is a rare condition. The tumor consists of both epithelial and mesenchymal cell lines and tends to behave aggressively. It has clinical features like that of invasive breast carcinoma but sometimes there can be diagnostic confusion as it can mimic or present as breast abscess. Treatment is multimodal. Surgery plays the vital role. Post-op radiation and chemo are indicated. Hormone therapy is usually inapplicable as most of the time, it is hormone receptor negative.

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