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1.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38193555

RESUMO

We present a comprehensive study using dissipative particle dynamics simulations to investigate phase separation kinetics (PSK) in three-dimensional (3d) polymeric fluids under random photo-illumination. We consider two scenarios: polymer blends with active radicals at one end of each immiscible chain and block copolymer (BCP) melts with photosensitive bonds linking incompatible blocks. The phase separation (PS) is induced by temperature quench of the initial homogeneously mixed system. Simultaneously, the system experiences random photo-illumination, simulated by two concurrent random events: (a) the recombination of active radicals in polymer blends and (b) the breaking of photosensitive bonds in BCP chains. Variations in the bond-breaking probability, Pb, mimic the change in light intensity. The length scale follows power law growth, R(t) ∼ tϕ, where ϕ represents the growth exponent. Increasing Pb results in a gradual transition in growth kinetics from micro-PS to macro-PS, accompanied by corresponding transition probabilities for both systems. Micro-PSK dominates the evolution process at low Pb values. The scaling functions exhibit data overlap for most scaled distances, indicating the statistical self-similarity of evolving patterns. Our study enhances the understanding of PSK in polymeric fluids, revealing the impact of photosensitive bonds and active radicals. Furthermore, it suggests the potential for designing novel polymeric materials with desired properties.

2.
Ergonomics ; : 1-17, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38192115

RESUMO

The cross-sectional study aimed to investigate the relationship between work-related factors, perceived work fatigue (PWF) and musculoskeletal disorders (MSDs) among handicraft artisans. 364 artisans participated in a questionnaire survey, and a structural equation model (SEM) was developed to explore the direct and indirect relationships between these factors using partial least squares analysis. The SEM explained 98.2% of the variance in MSDs and revealed that exposure to biomechanical factors had a direct impact on PWF and MSDs, with PWF mediating the effect of biomechanical factors on MSDs. Additionally, job demand was found to be positively associated with MSDs, while job control and social support reduced the risk of MSDs. The findings underscore the importance of strategic initiatives to mitigate the risk of developing MSDs among artisans. The study also highlights the potential of SEM as a novel framework for understanding the complex pathogenesis of MSDs in occupational health research.Practitioner summary: The study sought to comprehensively examine the intricate relationships among work-related factors, PWF, and MSDs. To achieve this, an SEM approach was employed to capture both direct and indirect relationships between these factors, employing partial least squares analysis. Findings revealed SEM as an innovative framework for understanding the intricate development of MSDs.

3.
J Nematol ; 56(1): 20240007, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38510971

RESUMO

Anguina tritici, the wheat seed gall nematode, causes the 'ear-cockle' or seed gall disease of wheat (Triticum sp.), leading to an extensive decline of yield (30-70%) in underdeveloped wheat cultivating countries of the world. The nematode is known to survive in anhydrobiotic conditions for up to 32 years. Here, we present the first transcriptome assembly of A. tritici, which will be a valuable resource for understanding the genes responsible for nematode survival and above-ground plant parasitism. The final 133.2 Mb assembly consists of 105606 open reading frames (including isoforms) with the following BUSCO scores against Nematoda database: 80.3% complete (16.4% single copy and 63.9% duplicated), 2.1% fragmented, and 17.6% missing.

4.
J Food Sci Technol ; 61(3): 503-515, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38327858

RESUMO

Goat milk has achieved significant place in human diet owing to its enormous therapeutic properties. There exists a scope of value-addition of goat milk to potentiate its health benefits by incorporating herbs and plants. Giloy (Tinospora cordifolia), a traditional medicinal plant with rich bioactive composition, can enhance the bioactive properties and shelf-life of goat milk. To this end, a study was conducted to develop shelf-stable giloy-goat milk beverage (GGB) by adding debittered giloy juice to goat milk (GM) and analyse the detailed product profile including proximate composition, bioactive properties, sensory, rheological, and structural characterisation. GGB resulted in two-fold increase (P < 0.05) in antioxidant activity and total phenolic content, thus enhancing the bioactive properties of the beverage as compared to GM. Further, increase in the particle size of GGB was observed along with components interaction, which was confirmed by FTIR, scanning electron and fluorescent microscopy. Storage stability studies indicated that bioactive properties of GGB remained unaffected (P > 0.05) by the sterilization process up to 90 days and sensory characteristics were not compromised till 105 days of storage. Therefore, the developed GGB is considered to be a shelf-stable beverage that retains its bioactive and sensory properties even after sterilization, making it a promising functional dairy product.

5.
J Biol Chem ; 298(9): 102352, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35940306

RESUMO

Drug resistance by pathogenic microbes has emerged as a matter of great concern to mankind. Microorganisms such as bacteria and fungi employ multiple defense mechanisms against drugs and the host immune system. A major line of microbial defense is the biofilm, which comprises extracellular polymeric substances that are produced by the population of microorganisms. Around 80% of chronic bacterial infections are associated with biofilms. The presence of biofilms can increase the necessity of doses of certain antibiotics up to 1000-fold to combat infection. Thus, there is an urgent need for strategies to eradicate biofilms. Although a few physicochemical methods have been developed to prevent and treat biofilms, these methods have poor efficacy and biocompatibility. In this review, we discuss the existing strategies to combat biofilms and their challenges. Subsequently, we spotlight the potential of enzymes, in particular, polysaccharide degrading enzymes, for biofilm dispersion, which might lead to facile antimicrobial treatment of biofilm-associated infections.


Assuntos
Anti-Infecciosos , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Polissacarídeos
6.
J Dairy Res ; 90(2): 205-212, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37264806

RESUMO

Eggnog, a dairy-based beverage, comprises both milk and egg proteins. We aimed at optimizing the eggnog formulation using Box-Behnken design of response surface methodology. The combined effects of milk (60-75), cream (25-35) and eggnog base (6-8, all three as g 100/ml) were investigated on heat coagulation time, viscosity and thermal gelation temperature. ANOVA indicated that experimental data were well explained by a quadratic model with high check values (R2 > 0.94) and non-significant lack of fit tests. Based on the responses, an optimized formulation of eggnog with 60.0 milk, 25.0 cream and 6.50 eggnog base (as g 100/ml), could be considered best for manufacturing eggnog with desired attributes. This optimized formulation was characterized for physico-chemical, microbial and sensory attributes and the results indicated significantly higher fat and protein content than control formulation, but lesser lactose and total sugar content. Significantly higher viscosity, heat stability and lower thermal gelation temperature were also observed for the optimized formulation. Coliform, yeast and mold, E. coli and Salmonella counts were not detected in any sample but a significantly lower total plate count was observed for the optimized formulation.


Assuntos
Escherichia coli , Leite , Animais , Leite/química , Temperatura , Bebidas/análise , Temperatura Alta
7.
Am J Orthod Dentofacial Orthop ; 164(5): 712-727, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37409990

RESUMO

INTRODUCTION: The increased use of social networking sites, such as Instagram (Meta Platforms, Menlo Park, Calif), has been silently affecting facial satisfaction among patients. However, the potential of Instagram to motivate participants for orthodontic treatment when used with an adjunct, a photograph editing software, is yet to be assessed. METHODS: From the initial 300 participants, 256 were included and randomly divided into an experimental group (participants were asked to provide their frontal smiling photograph) and a control group. The photographs received were corrected using photograph editing software and were shown along with other ideal smile photographs in an Instagram account to the experimental group, whereas the control group participants had access to only the ideal smile photographs. After browsing, the participants were given a modified version of the Malocclusion-Related Quality of Life Questionnaire. RESULTS: Questions assessing the general perception about one's smile, comparison with peers, desire to undergo orthodontic treatment, and the role of socioeconomic status showed a statistically significant difference (P <0.05) as most of the control group participants were unsatisfied with their teeth, had less desire to undergo orthodontic treatment and did not feel family's financial income to be a hurdle, contrary to the experimental group participants. A statistically significant difference (P <0.05) was also seen in assessing external acceptance, speech difficulties, and the influence of Instagram on orthodontic treatment, whereas the influence of photograph editing software did not show the same. CONCLUSIONS: The study concluded that the experimental group participants were motivated to undergo orthodontic treatment after viewing their corrected photograph.


Assuntos
Má Oclusão , Mídias Sociais , Humanos , Sorriso , Qualidade de Vida , Má Oclusão/terapia , Face , Estética Dentária
8.
Am J Orthod Dentofacial Orthop ; 163(6): 851-857, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36740484

RESUMO

INTRODUCTION: This in vivo study evaluated the temperature changes in the pulp chamber at different exposure times using a monophasic light-emitting diode curing unit. METHODS: Forty-five patients (aged 13-25 years) requiring extraction of maxillary first premolars for orthodontic reasons were included in the study. After access opening, the temperature rise was recorded when exposed to monophasic light-emitting diode curing light (Elipar 3M ESPE; Pymble, New South Wales, Australia) at 5, 10, 15, and 20 seconds with K-type thermocouple probe. Teeth were atraumatically extracted on the same day. The results were analyzed with an analysis of variance and the Bonferroni test. RESULTS: There was a significant increase of 2.1°C ± 0.5°C of pulpal temperature in the maxillary first premolar tooth during exposure to a light curing unit from baseline to 20 seconds. The mean baseline temperature was 35.7°C ± 0.52°C. The highest mean temperature was recorded at 20 seconds (37.8°C ± 0.57°C), and the lowest mean temperature was recorded at 5 seconds (36.1°C ± 0.61°C). There were significant differences among each group (P <0.001) with a mean increase in pulpal temperature from baseline to exposure mode of 5, 10, 15, and 20 seconds. CONCLUSIONS: The study results reveal a statistically significant increase in pulpal temperature with a monophasic curing light, which can be used for up to 20 seconds without causing any detrimental effects on the pulp.


Assuntos
Cavidade Pulpar , Polpa Dentária , Humanos , Temperatura , Dente Pré-Molar , Austrália , Lâmpadas de Polimerização Dentária , Resinas Compostas
9.
J Nematol ; 55(1): 20230031, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38026554

RESUMO

Anguina tritici is the first plant-parasitic nematode described in literature, dating back to the year 1743. It is responsible for causing earcockle (seed gall) and tundu diseases in wheat and rye. Notably, this nematode has been observed to survive in an anhydrobiotic state for up to 32 years within wheat seed galls. These exceptional characteristics have inspired the sequencing of the A. tritici genome. In this study, we present the initial draft genome of A. tritici, obtained using the Illumina MiSeq platform with coverage of 60-fold. The genome is estimated to have a size of 164 Mb and comprises 39,965 protein-coding genes, exhibiting a GC content of 39.1%. The availability of this genome data will serve as a foundation for future functional biological investigations, particularly for genes whose functions remain unknown to this day.

10.
J Food Sci Technol ; 60(11): 2705-2724, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37711574

RESUMO

Thermal processing remains the key processing technology for food products. However, there are some limitations for thermal processing such as loss of sensory and nutritional quality. Furthermore, nowadays consumers are looking forward for fresh like products which are free from chemical preservatives, yet having longer shelf life. Thus, alternative processing techniques are gaining popularity among food processors to replace conventional thermal processing keeping nutritional quality, sensory attributes and food safety in mind. The alternative processing techniques such as ultrasound, gamma irradiation, high pressure processing and microwave treatment causes several modifications (structural changes, effects on swelling and solubility index, gelatinization behaviour, pasting or rheological properties, retrogradation and cooking time) in physicochemical and functional properties of pulse starches which offers several advantages from commercial point of view. This review aims to summarize the effect of different alternative processing techniques on the structure, solubility, gelatinization, retrogradation and pasting properties of various pulse starches. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05557-3.

11.
J Food Sci Technol ; 60(4): 1209-1221, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36936112

RESUMO

Khoa and khoa based products (burfi, peda, kalakand, milk cake, etc.) are a category of traditional dairy products of Indian subcontinent. They are prepared by open pan desiccation along with stirring and scraping of milk to the desired consistency, followed by addition of sugar and / or colour and flavoring ingredients. The peculiar sensory attributes developed during their course of preparation makes them unique, but their short shelf-life is a major challenge faced by the dairy industries. They are spoiled mainly because of yeast and mold growth along with detrimental changes in the sensory attributes. This review describes various preservation techniques explored in the last two decades such as packaging interventions, modified atmospheric and active packaging, chemical preservation, water activity modification, natural preservation, thermal treatments, bio-preservation, etc. which can be used either singly or in combination (hurdle technology), to enhance the shelf life of these milk products.

12.
J Antimicrob Chemother ; 77(12): 3376-3389, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36177811

RESUMO

OBJECTIVES: Salmonella enterica serovar Typhimurium is one of the significant non-typhoidal Salmonella serovars that causes gastroenteritis. The rapid development of antimicrobial resistance necessitates studying new antimicrobials and their therapeutic targets in this pathogen. Our study aimed to investigate the role of four prominent outer membrane porins of S. Typhimurium, namely OmpA, OmpC, OmpD and OmpF, in developing resistance against ceftazidime and meropenem. METHODS: The antibiotic-mediated inhibition of bacterial growth was determined by measuring the absorbance and the resazurin assay. DiBAC4 (Bis-(1,3-Dibutylbarbituric Acid)Trimethine Oxonol), 2,7-dichlorodihydrofluoroscein diacetate (DCFDA) and propidium iodide were used to determine the outer membrane depolarization, reactive oxygen species (ROS) generation and subsequent killing of Salmonella. The expression of oxidative stress-response and efflux pump genes was quantified by quantitative RT-qPCR. HPLC was done to determine the amount of antibiotics that entered the bacteria. The damage to the bacterial outer membrane was studied by confocal and atomic force microscopy. The in vivo efficacy of ceftazidime and meropenem were tested in the C57BL/6 mouse model. RESULTS: Deleting ompA reduced the survival of Salmonella in the presence of ceftazidime and meropenem. Massive outer membrane depolarization and reduced expression of oxidative stress-response genes in S. Typhimurium ΔompA hampered its growth in the presence of antibiotics. The enhanced uptake of antibiotics and decreased expression of efflux pump genes in S. Typhimurium ΔompA resulted in damage to the bacterial outer membrane. The clearance of the S. Typhimurium ΔompA from C57BL/6 mice with ceftazidime treatment proved the role of OmpA in rendering protection against ß-lactam antibiotics. CONCLUSIONS: OmpA protects S. Typhimurium from two broad-spectrum ß-lactam antibiotics, ceftazidime and meropenem, by maintaining the stability of the outer membrane.


Assuntos
Antibacterianos , Proteínas da Membrana Bacteriana Externa , Salmonella typhimurium , Animais , Camundongos , Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Ceftazidima/farmacologia , Meropeném/farmacologia , Camundongos Endogâmicos C57BL , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
13.
Environ Res ; 215(Pt 1): 114199, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36058281

RESUMO

In the present study, the microbial community residing at different depths of the landfill was characterized to assess their roles in serving as a methane sink. Physico-chemical characterization revealed the characteristic signatures of anaerobic degradation of organic matter in the bottom soil (50-60 cm) and, active process of aerobic denitrification in the top soil (0-10 cm). This was also reflected from the higher abundance of bacterial domain in the top soil metagenome represented by dominant phyla Proteobacteria and Actinobacteria which are prime decomposers of organic matter in landfill soils. The multiple fold higher relative abundances of the two most abundant genera; Streptomyces and Intrasporangium in the top soil depicted greater denitrifying taxa in top soil than the bottom soil. Amongst the aerobic methanotrophs, the genera Methylomonas, Methylococcus, Methylocella, and Methylacidiphilum were abundantly found in the top soil metagenome that were essential for oxidizing methane generated in the landfill. On the other hand, the dominance of archaeal domain represented by Methanosarcina and Methanoculleus in the bottom soil highlighted the complete anaerobic digestion of organic components via acetoclasty, carboxydotrophy, hydrogenotrophy, methylotrophy. Functional characterization revealed a higher abundance of methane monooxygenase gene in the top soil and methyl coenzyme M reductase gene in the bottom soil that correlated with the higher relative abundance of aerobic methanotrophs in the top soil while methane generation being the active process in the highly anaerobic bottom soil in the landfill. The activity dependent abundance of endogenous microbial communities in the different zones of the landfill was further validated by microcosm studies in serum bottles which established the ability of the methanotrophic community for methane metabolism in the top soil and their potential to serve as sink for methane. The study provides a better understanding about the methanotrophs in correlation with their endogenous environment, so that these bacteria can be used in resolving the environmental issues related to methane and nitrogen management at landfill site.


Assuntos
Metano , Solo , Bactérias/genética , Bactérias/metabolismo , Metagenoma , Nitrogênio , Oxirredução , Solo/química , Microbiologia do Solo , Instalações de Eliminação de Resíduos
14.
Int Arch Occup Environ Health ; 95(5): 1129-1145, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34817669

RESUMO

PURPOSE: Precision handicraft workers are often exposed to stressful postures and poor working conditions while performing different jobs, that are directly associated with the development of musculoskeletal disorders (MSDs). This cross-sectional study aimed at evaluating the prevalence of MSDs and contributing risk factors among male precision handicraft workers. METHODS: 334 handicraft workers involved in different precision activities: 125 gemstone cutters, 98 miniature painters, and 111 metal craft workers, were surveyed. Information about the prevalence of musculoskeletal symptoms and work-related factors was collected using the self-reported questionnaire and direct observation methods, viz. rapid upper limb assessment (RULA) and rapid entire body assessment (REBA). Chi-square test was performed to analyze the association of MSD symptoms between the handicraft occupations. Further, binary logistic regression was used to identify the potential risk factors for MSD symptoms among workers. RESULTS: In all occupational groups, most participants reported high prevalence of MSDs primarily in the neck (61.6%), lower back (74.8%), and knee (54.7%) regions. Results revealed that age, work experience, prolonged work hours, sustained awkward posture, continuous work without break, extensive work pressure, and poor job control increased the risk of MSD symptoms in different body regions, while with a higher level of education, MSDs in the neck and lower back regions reduced. CONCLUSION: The findings indicated incompatibility between precision handicraft workers and the occupational environment. Logistic regression models showed significant contribution of physical and psychosocial work-related factors in developing MSD symptoms. Ergonomic interventions are imperative to evade adverse consequences on the occupational health of precision craft workers.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Estudos Transversais , Ergonomia , Humanos , Masculino , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Prevalência , Fatores de Risco , Postura Sentada , Inquéritos e Questionários
15.
World J Microbiol Biotechnol ; 38(8): 140, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35705700

RESUMO

Municipal landfills are known for methane production and a source of nitrate pollution leading to various environmental issues. Therefore, this niche was selected for the isolation of one-carbon (C1) utilizing bacteria with denitrifying capacities using anaerobic enrichment on nitrate mineral salt medium supplemented with methanol as carbon source. Eight axenic cultures were isolated of which, isolate AAK/M5 demonstrated the highest methanol removal (73.28%) in terms of soluble chemical oxygen demand and methane removal (41.27%) at the expense of total nitrate removal of 100% and 33% respectively. The whole genome characterization with phylogenomic approach suggested that the strain AAK/M5 could be assigned to Pseudomonas aeruginosa with close neighbours as type strains DVT779, AES1M, W60856, and LES400. The circular genome annotation showed the presence of complete set of genes essential for methanol utilization and complete denitrification process. The study demonstrates the potential of P. aeruginosa strain AAK/M5 in catalysing methane oxidation thus serving as a methane sink vis-à-vis utilization of nitrate. Considering the existence of such bacteria at landfill site, the study highlights the need to develop strategies for their enrichment and designing of efficient catabolic activity for such environments.


Assuntos
Solo , Resíduos Sólidos , Bactérias/metabolismo , Carbono/metabolismo , Desnitrificação , Genômica , Metano/metabolismo , Metanol/metabolismo , Nitratos/metabolismo , Oxirredução , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Solo/química , Instalações de Eliminação de Resíduos
16.
J Food Sci Technol ; 59(8): 3073-3085, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35872713

RESUMO

Abstract: A dairy-cereal based composite substrate was prepared from whey-skim milk (60:40 v/v), germinated pearl millet flour (4.73% w/v) and liquid barley malt extract (3.27% w/v) and fermented using probiotic strain Lactobacillus acidophilus NCDC-13. Probiotic fermentation increased whiteness index, viscosity and water holding capacity of unfermented substrate. Fermentation caused a reduction in total solids, fat, ash and total dietary fibre content and increment in protein content. Fermentation brought a highly significant reduction in phytic acid (78%) and polyphenol (46%) content. The protein and starch digestibility increased significantly. The HCl- extractability of Ca, Fe, Mg and Zn of unfermented substrate was 32%, 25%, 64% and 17% respectively, which increased to 73%, 50%, 83% and 65% respectively after fermentation. Fermentation resulted in 77% decrease in phytate P as % of total P and significant increase in free P. The current investigation revealed that probiotic fermentation improved nutritional attributes of the composite substrate substantially. The low cost nutritionally enriched probiotic substrate can be utilized for preparation of a wide range of low- cost probiotic foods to address malnutrition and enhance immunity of common population.

17.
J Food Sci Technol ; 59(3): 956-967, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35185202

RESUMO

Ultrafiltration (UF) of buffalo skim milk (BSM) induces changes in its delicate protein-mineral equilibrium. Appling UF causes alteration in chemical composition of UF retentates as a function of protein concentration that adversely affect their physical and rheological properties. Hence, present investigation was targeted to evaluate the changes taking place in heat stability, ζ-potential, particle size, apparent viscosity, pH, turbidity and crossover temperature of storage (G') and loss (G″) modulus of high-protein BSM based UF retentates as a function of homogenization and sodium hydrogen phosphate (SHP) addition. The UF of BSM (heat treated at 85 ± 1 °C for 5 min), significantly increased (P < 0.05) the concentration of protein, fat and minerals, however, it decreased the concentration of lactose and water soluble minerals in UF retentates over BSM. The SHP addition significantly increased (P < 0.05) pH, crossover temperature of G' and G″, ζ-potential, while significantly decreased (P < 0.05) turbidity and particle size in most non-homogenized retentates. Heat coagulation time (HCT) of control and treated UF retentates were at par (P > 0.05) with each other, however, variations were observed in their viscosity values. Rheological behaviour of most of these UF retentates was efficiently described by Bingham model. The correlation among ζ-potential, particle size, apparent viscosity, pH, turbidity, HCT and crossover temperatures G' and G″ of evaluated samples was also established. Overall, this study concluded that 0.5-6% SHP addition in non-homogenized UF retentates, markedly improved their milk protein stability as advocated by higher ζ-potential, G' and G″ crossover temperature values. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05097-2.

18.
Soft Matter ; 17(7): 1802-1813, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33399613

RESUMO

Using a dissipative particle dynamics (DPD) simulation method, we study the phase separation dynamics in block copolymer (BCP) melts in d = 3, subjected to external stimuli such as light. An initial homogeneous BCP melt is rapidly quenched to a temperature T < Tc, where Tc is the critical temperature. We then allow the system to undergo alternate light "on" and "off" cycles. An on-cycle breaks the stimuli-sensitive bonds connecting both the blocks A and B in the BCP melt, and during the off-cycle, the broken bonds recombine. By simulating the effect of light, we isolate scenarios where phase separation begins with the light off (set 1); the cooperative interactions within the system allow it to undergo microphase separation. When the phase separation starts with the light on (set 2), the system undergoes macrophase separation due to bond breaking. Here, we report the role of alternate cycles on domain morphology by varying the bond-breaking probability for both set 1 and set 2, respectively. We observe that the scaling functions depend upon the conditions mentioned above that change the time scale of the evolving morphologies in various cycles. However, in all the cases, the average domain size respects the power-law growth: R(t) ∼tφ at late times, where φ is the dynamic growth exponent. After a short-lived diffusive growth (φ∼ 1/3) at early times, φ illustrates a crossover from the viscous hydrodynamic (φ∼ 1) to the inertial hydrodynamic (φ∼ 2/3) regimes at late times.

19.
Appl Microbiol Biotechnol ; 105(3): 1107-1121, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33417040

RESUMO

Mixed viral infections are common in fields and frequently exacerbate disease severity via synergistic interactions among individual viral genomic components leading to major crop loss. Two predominant species of tomato-infecting begomoviruses, Tomato leaf curl New Delhi virus (ToLCNDV) and Tomato leaf curl Gujarat virus (ToLCGuV), are known to cause severe leaf curl disease of tomato in India. Previously, we have demonstrated asymmetric synergism between these two distinct begomovirus species during mixed infection in solanaceous hosts. In the present study, we have identified the underlying proteins that positively regulate asymmetric synergism and their effect on plant defense machinery. During co-infection, the AC2 and AV2 of ToLCGuV enhanced ToLCNDV DNA accumulation in Nicotiana benthamiana as well as in their natural host, tomato. Furthermore, we found that AC2 and AV2 of ToLCNDV and AV2 of ToLCGuV play a critical role in suppression of post transcriptional gene silencing (PTGS) machinery. Taken together, AC2 and AV2 encoded proteins of ToLCGuV are the crucial viral factors promoting asymmetric synergism with ToLCNDV. KEY POINTS: • Begomoviral suppressors play vital roles in viral synergism. • AC2 and AV2 of ToLCGuV asymmetrically enhance ToLCNDV accumulation. • AC2 and AV2 of ToLCNDV and ToLCGuV AV2 are major PTGS suppressors.


Assuntos
Begomovirus , Solanum lycopersicum , Begomovirus/genética , DNA Viral , Índia , Doenças das Plantas , Nicotiana
20.
J Assoc Physicians India ; 69(7): 11-12, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34431265

RESUMO

INTRODUCTION: As India recovers from the two waves of the Covid-19 pandemic, its sequelae are posing a new challenge to the physician. These may vary from fatigue and myalgia to persistent, and even worsening breathlessness, due to pulmonary fibrosis. Management of post-COVID-19 pulmonary fibrosis is currently limited to symptomatic management and largely an unexplored aspect. OBJECTIVES: To draw attention to the imminent threat of post-COVID-19 interstitial lung disease (PC-ILD) in COVID survivors through a case series. METHODS: A retrospective analysis of data was done in patients admitted with severe COVID in December 2020 at our tertiary care hospital, and who had a prolonged stay with symptoms and signs suggestive of pulmonary fibrosis. HRCT was done to make a diagnosis of pulmonary fibrosis or ILD. Three such patients were identified. RESULTS: All the three cases were laboratory proven SARS CoV-2 positive cases and had developed pulmonary fibrosis, with traction bronchiectasis, termed here as PC-ILD (Post Covid-Interstitial Lung Disease). Two of them survived and had improved oxygen saturation on room air at three-month follow-up, while one patient had developed arrhythmia and died. CONCLUSION: PC- ILD is one of the emerging complications of COVID-19 pneumonia. A proactive follow-up programme should be undertaken to identify and manage this looming epidemic.


Assuntos
COVID-19 , Doenças Pulmonares Intersticiais , Humanos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/etiologia , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X
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