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1.
Chemphyschem ; 25(10): e202300950, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38511569

RESUMO

First principles-based computational and theoretical methods are constantly evolving trying to overcome the many obstacles towards a comprehensive understanding of electrochemical processes on an atomistic level. One of the major challenges has been the determination of reaction energetics under a constant potential. Here, a theoretical framework was proposed applying standard electronic structure methods and extrapolating to the infinite-cell size limit where reactions do not alter the potential. Today, electronically grand canonical modifications to electronic structure methods, holding the potential constant by varying the number of electrons in a finite simulation cell, become increasingly popular. In this perspective, we show that these two schemes are thermodynamically equivalent. Further, we link these methods to capacitive models of the interface, in the limit that the capacitance of the charging components (whether continuum or atomistic) are equal and invariant along the reaction pathway. We benchmark the three approaches with an example of alkali cation adsorption on Pt(111) showing that all three approaches converge in the cases of Li, Na and K. For Cs, however, strong deviation from the ideal conditions leads to a spread in the respective results. We discuss the latter by highlighting the cases of broken equivalence and assumptions among the approaches.

2.
Physiol Plant ; 176(3): e14396, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887929

RESUMO

Phosphorus (P) is a crucial macronutrient required for normal plant growth. Its effective uptake from the soil is a trait of agronomic importance. Natural variation in maize (339 accessions) root traits, namely root length and number of primary, seminal, and crown roots, root and shoot phosphate (Pi) contents, and root-to-shoot Pi translocation (root: shoot Pi) under normal (control, 40 ppm) and low phosphate (LP, 1 ppm) conditions, were used for genome-wide association studies (GWAS). The Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) model of GWAS provided 23 single nucleotide polymorphisms (SNPs) and 12 relevant candidate genes putatively linked with root Pi, root: shoot Pi, and crown root number (CRN) under LP. The DNA-protein interaction analysis of Zm00001d002842, Zm00001d002837, Zm00001d002843 for root Pi, and Zm00001d044312, Zm00001d045550, Zm00001d025915, Zm00001d044313, Zm00001d051842 for root: shoot Pi, and Zm00001d031561, Zm00001d001803, and Zm00001d001804 for CRN showed the presence of potential binding sites of key transcription factors like MYB62, bZIP11, ARF4, ARF7, ARF10 and ARF16 known for induction/suppression of phosphate starvation response (PHR). The in-silico RNA-seq analysis revealed up or down-regulation of candidate genes along with key transcription factors of PHR, while Uniprot analysis provided genetic relatedness. Candidate genes that may play a role in P uptake and root-to-shoot Pi translocation under LP are proposed using common PHR signaling components like MYB62, ARF4, ARF7, ARF10, ARF16, and bZIP11 to induce changes in root growth in maize. Candidate genes may be used to improve low P tolerance in maize using the CRISPR strategy.


Assuntos
Estudo de Associação Genômica Ampla , Fosfatos , Raízes de Plantas , Polimorfismo de Nucleotídeo Único , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Fosfatos/metabolismo , Fosfatos/deficiência , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Desequilíbrio de Ligação/genética
3.
Environ Res ; 244: 117707, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008206

RESUMO

The production and utilization of plastics may prove beneficial, but the environmental impact suggests the opposite. The single-use plastics (SUP) and conventional plastics are harmful to the environment and need prompt disposal. Bioplastics are increasingly being considered as a viable alternative to conventional plastics due to their potential to alleviate environmental concerns such as greenhouse gas emissions and pollution. However, the previous reviews revealed a lack of consistency in the methodologies used in the Life Cycle Assessments (LCAs), making it difficult to compare the results across studies. The current study provides a systematic review of LCAs that assess the environmental impact of bioplastics. The different mechanical characteristics of bio plastics, like tensile strength, Young's modulus, flexural modulus, and elongation at break are reviewed which suggest that bio plastics are comparatively much better than synthetic plastics. Bioplastics have more efficient mechanical properties compared to synthetic plastics which signifies that bioplastics are more sustainable and reliable than synthetic plastics. The key challenges in bioplastic adoption and production include competition with food production for feedstock, high production costs, uncertainty in end-of-life management, limited biodegradability, lack of standardization, and technical performance limitations. Addressing these challenges requires collaboration among stakeholders to drive innovation, reduce costs, improve end-of-life management, and promote awareness and education. Overall, the study suggests that while bioplastics have the potential to reduce environmental impact, further research is needed to better understand their life cycle and optimize their end-of-life (EoL) management and production to maximize their environmental benefits.


Assuntos
Poluição Ambiental , Plásticos , Biopolímeros
4.
Eur Respir J ; 61(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36229049

RESUMO

BACKGROUND: Identifying risk factors for poor outcomes can help with risk stratification and targeting of treatment. Risk factors for mortality and exacerbations have been identified in bronchiectasis but have been almost exclusively studied in European and North American populations. This study investigated the risk factors for poor outcome in a large population of bronchiectasis patients enrolled in India. METHODS: The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) and Respiratory Research Network of India (EMBARC-India) registry is a prospective observational study of adults with computed tomography-confirmed bronchiectasis enrolled at 31 sites across India. Baseline characteristics of patients were used to investigate associations with key clinical outcomes: mortality, severe exacerbations requiring hospital admission, overall exacerbation frequency and decline in forced expiratory volume in 1 s. RESULTS: 1018 patients with at least 12-month follow-up data were enrolled in the follow-up study. Frequent exacerbations (≥3 per year) at baseline were associated with an increased risk of mortality (hazard ratio (HR) 3.23, 95% CI 1.39-7.50), severe exacerbations (HR 2.71, 95% CI 1.92-3.83), future exacerbations (incidence rate ratio (IRR) 3.08, 95% CI 2.36-4.01) and lung function decline. Coexisting COPD, dyspnoea and current cigarette smoking were similarly associated with a worse outcome across all end-points studied. Additional predictors of mortality and severe exacerbations were increasing age and cardiovascular comorbidity. Infection with Gram-negative pathogens (predominantly Klebsiella pneumoniae) was independently associated with increased mortality (HR 3.13, 95% CI 1.62-6.06), while Pseudomonas aeruginosa infection was associated with severe exacerbations (HR 1.41, 95% CI 1.01-1.97) and overall exacerbation rate (IRR 1.47, 95% CI 1.13-1.91). CONCLUSIONS: This study identifies risk factors for morbidity and mortality among bronchiectasis patients in India. Identification of these risk factors may support treatment approaches optimised to an Asian setting.


Assuntos
Bronquiectasia , Adulto , Humanos , Seguimentos , Bronquiectasia/terapia , Bronquiectasia/tratamento farmacológico , Pulmão , Sistema de Registros , Progressão da Doença
5.
Respirology ; 28(8): 744-757, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37301540

RESUMO

For most patients, asthma can be effectively managed using inhaled medications. However, patients who have severe and/or uncontrolled asthma, or who experience exacerbations, may require systemic corticosteroids (SCSs) to maintain asthma control. Although SCS are highly effective in this regard, even modest exposure to these medications can increase the risk for long-term, adverse health outcomes, such as type 2 diabetes, renal impairment, cardiovascular disease and overall mortality. Clinical and real-world data from studies investigating asthma severity, control and treatment practices around the globe have suggested that SCS are overused in asthma management, adding to the already substantial healthcare burden experienced by patients. Throughout Asia, although data on asthma severity, control and SCS usage are limited and vary widely among countries, available data strongly suggest a pattern of overuse consistent with the broader global trend. Coordinated changes at the patient, provider, institutional and policy levels, such as increasing disease awareness, promoting better adherence to treatment guidelines and increasing availability of safe and effective alternatives to SCS, are likely necessary to reduce the SCS burden for patients with asthma in Asia.


Assuntos
Antiasmáticos , Asma , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Asma/terapia , Corticosteroides , Ásia/epidemiologia , Antiasmáticos/uso terapêutico
6.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677545

RESUMO

In the present scenario, the research is now being focused on the naturally occurring polymers that can gradually replace the existing synthetic polymers for the development of bio composites having applications in medical surgeries and human implants. With promising mechanical properties and bio compatibility with human tissues, poly lactic acid (PLA) is now being viewed as a future bio material. In order to examine the applicability of PLA in human implants, the current article sheds light on the synthesis of PLA and its various copolymers used to alter its physical and mechanical properties. In the latter half, various processes used for the fabrication of biomaterials are discussed in detail. Finally, biomaterials that are currently in use in the field of biomedical (Scaffolding, drug delivery, tissue engineering, medical implants, derma, cosmetics, medical surgeries, and human implants) are represented with respective advantages in the sphere of biomaterials.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Humanos , Poliésteres , Polímeros , Alicerces Teciduais
7.
Beilstein J Org Chem ; 19: 231-244, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36895429

RESUMO

An operationally simple and metal-free approach is described for the synthesis of pyrazole-tethered thioamide and amide conjugates. The thioamides were generated by employing a three-component reaction of diverse pyrazole C-3/4/5 carbaldehydes, secondary amines, and elemental sulfur in a single synthetic operation. The advantages of this developed protocol refer to the broad substrate scope, metal-free and easy to perform reaction conditions. Moreover, the pyrazole C-3/5-linked amide conjugates were also synthesized via an oxidative amination of pyrazole carbaldehydes and 2-aminopyridines using hydrogen peroxide as an oxidant.

8.
Cell Mol Biol (Noisy-le-grand) ; 67(4): 68-82, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35809301

RESUMO

C-phycocyanin (C-PC), the integral blue-green algae (BGA) constituent has been substantially delineated for its biological attributes. Numerous reports have illustrated differential extraction and purification techniques for C-PC, however, there exists paucity in a broadly accepted process of its isolation. In the present study, we reported a highly selective C-PC purification and characterization method from nontoxic, filamentous and non-heterocystous cyanobacterium Plectonema sp. C-PC was extracted by freeze-thawing, desalted and purified using ion-exchange chromatography. The purity of C-PC along with its concentration was found to be 4.12 and 245 µg/ml respectively.  Comparative characterization of standard and purified C-PC was performed using diverse spectroscopic techniques namely Ultra Violet-visible, fluorescence spectroscopy and Fourier transform infrared (FT-IR). Sharp peaks at 620 nm and 350 nm with UV-visible and FT-IR spectroscopy respectively, confirmed amide I bands at around 1638 cm-1 (C=O stretching) whereas circular dichroism (CD) spectra exhibited α-helix content of secondary structure of standard 80.59% and 84.59% of column purified C-PC. SDS-PAGE exhibited two bands of α and ß subunits 17 and 19 kDa respectively. HPLC evaluation of purified C-PC also indicated a close resemblance of retention peak time (1.465 min, 1.234 min, 1.097 min and 0.905 min) with standard C-PC having retention peak timing of 1.448 min, 1.233 min and 0.925 min. As a cautious approach, the purified C-PC was further lyophilized to extend its shelf life as compared to its liquid isoform. To evaluate the bioactive potential of the purified C-PC in silico approach was attempted. The molecular docking technique was carried out of C-PC as a ligand-protein with free radicals and α-amylase, α-glucosidase, glycogen synthase kinase-3 and glycogen phosphorylase enzymes as receptors to predict the free radical scavenging (antioxidant) and to target antidiabetic property of C-PC. In both receptors free radicals and enzymes, ligand C-PC plays an important role in establishing interactions within the cavity of active sites. These results established the antioxidant potential of C-PC and also give a clue towards its antidiabetic potential warranting further research.


Assuntos
Cianobactérias , Plectonema , Antioxidantes/química , Antioxidantes/farmacologia , Cianobactérias/química , Radicais Livres , Hipoglicemiantes , Ligantes , Simulação de Acoplamento Molecular , Ficocianina/química , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Environ Res ; 213: 113676, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35728639

RESUMO

India's air quality is in a dismal state, with many studies ascribing it to PM2.5. Most of these corroborate that carbonaceous aerosol (CA) constitute significant fraction of PM2.5. However, investigations on the effect of long-term meteorological or emission changes on PM2.5 and its components, and their associated health effects are rare. In this work, WRF-Chem simulations for three seasons over four years (2016-2019) were carried out to cogitate the spatial and temporal changes in PM2.5 and its components in India. Model predicted PM2.5 concentrations were in good agreement with the ground-based observations for 25 cities. PM2.5 was highest in winter and lowest in pre-monsoon. PM2.5 reduced by ∼8% in Indo-Gangetic Plain (IGP) but increased by ∼38% and ∼130% in south and northeast India, respectively, from 2016 to 2019. IGP witnessed three times higher average PM2.5 concentrations than south India. No significant interannual change in CA contributions was observed, however, it peaked in the winter season. Other inorganics (OIN) were the major component of PM2.5, contributing more than 40%. Primary organic aerosol (POA) fractions were higher in north India, while secondary inorganic aerosol (SIA) dominated south India. Transport and residential sectors were the chief contributors to CA across India. Biomass burning contributed up to ∼23% of PM2.5 in regions of IGP during post-monsoon, with CA fractions up to 50%. Associations between PM2.5 and its components with daily inpatient admissions from a tertiary care centre in Delhi showed that PM2.5 and OIN had lower associations with daily hospital admissions than CA. Every 10 µg/m3 increase in POA, black carbon (BC), and secondary organic aerosol (SOA) were associated with ∼1.09%, ∼3.07% and ∼4.93% increase in the risk of daily hospital admissions. This invigorates the need for more policies targeting CA rather than PM2.5 to mitigate associated health risks, in India.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Índia , Material Particulado/análise , Estações do Ano
10.
Environ Res ; 212(Pt D): 113466, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35618010

RESUMO

Atmospheric polycyclic aromatic hydrocarbons (PAHs) are in high levels in developing countries like India. However, limited measurements are inadequate for better understanding of their ambient levels and health effects. This study predicted PAHs concentrations in atmosphere and estimated their sources and health risks in India in four representative months of winter, pre-monsoon, monsoon and post-monsoon in 2015 using an updated version of the Community Multiscale Air Quality model (CMAQ). Predicted PAHs were in agreement with observations from literature. Surface 16-PAHs were highest in winter, with a peak value of 2.5 µg/m3 and population-weighted average of 0.5 µg/m3 in northern and eastern India, where biomass burning and coal combustion were chief contributors. Pre-monsoon and monsoon had lower concentrations ∼0.2 µg/m3. The incremental lifetime cancer risk (ILCR) was greater than 4E-4 in many industrial and urban areas. Exposure to PAHs resulted in 7431 excess lifetime cancer cases. Coal combustion and biomass burning were major contributors to ILCR, followed by gas and oil activities. Much higher health risks were observed in urban than in rural areas. India showed much higher levels of total PAHs and cPAHs than the U.S but moderately less than China.


Assuntos
Poluentes Atmosféricos , Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Carvão Mineral/análise , Monitoramento Ambiental , Humanos , Índia , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Estações do Ano
11.
J Chem Phys ; 156(21): 214903, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35676144

RESUMO

We report the ion transport mechanisms in succinonitrile (SN) loaded solid polymer electrolytes containing polyethylene oxide (PEO) and dissolved lithium bis(trifluoromethane)sulphonamide (LiTFSI) salt using molecular dynamics simulations. We investigated the effect of temperature and loading of SN on ion transport and relaxation phenomenon in PEO-LiTFSI electrolytes. It is observed that SN increases the ionic diffusivities in PEO-based solid polymer electrolytes and makes them suitable for battery applications. Interestingly, the diffusion coefficient of TFSI ions is an order of magnitude higher than the diffusion coefficient of lithium ions across the range of temperatures and loadings investigated. By analyzing different relaxation timescales and examining the underlying transport mechanisms in SN-loaded systems, we find that the diffusivity of TFSI ions correlates excellently with the Li-TFSI ion-pair relaxation timescales. In contrast, our simulations predict distinct transport mechanisms for Li-ions in SN-loaded PEO-LiTFSI electrolytes. Explicitly, the diffusivity of lithium ions cannot be uniquely determined by the ion-pair relaxation timescales but additionally depends on the polymer segmental dynamics. On the other hand, the SN loading induced diffusion coefficient at a given temperature does not correlate with either the ion-pair relaxation timescales or the polymer segmental relaxation timescales.

12.
Sensors (Basel) ; 22(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35591144

RESUMO

The hydrogel materials are getting attention from the research due to their multidimensional usage in various fields. Chitosan is one of the most important hydrogels used in this regard. In this paper multifunctional binary graft copolymeric matrices of chitosan with monomer AA and various comonomers AAm and AN were prepared by performing free radical graft copolymerization in the presence of an initiator KPS. The binary grafting can be done at five different molar concentrations of binary comonomers at already optimized concentration of AA, KPS and other reaction conditions such as time, temperature, solvent amount, etc. Various optimum reaction conditions were investigated and presented in this work; the backbone as well as binary grafts Ch-graft-poly (AA-cop-AAm) and Ch-graft-poly (AA-cop-AN) were characterized via various physio-chemical techniques of analysis such as SEM analysis, Xray diffraction (XRD), TGA/DTA and FTIR. In the batch experiments, the binary grafts were investigated for the percent swelling with respect to pH (pH of 2.2, 7.0, 7.4 and 9.4) and time (contact time 1 to 24 h). Uploading and controllable in vitro release of the drug DS (anti-inflammatory) was examined with reverence to gastrointestinal pH and time. The binary grafts showed significantly better-controlled drug diffusion than the unmodified backbone. The kinetic study revealed that the diffusion of the drug occurred by the non-Fickian way. In the case of separation technologies, experiments (batch tests) were executed for the toxic bivalent metal ions Fe (II) and Pb (II) sorption from the aqueous media with respect to the parameters such as interaction period, concentration of fed metal ions in solution, pH and temperature. The binary grafted matrices showed superior results compared to chitosan. The kinetics study revealed that the matrices show pseudo-second order adsorption. The graft copolymer Ch-graft-poly (AA-cop-AAm) provided superior results in sustainable drug release as well as metal ion uptake. The study explored the potential of chitosan-based materials in the industry as well in the biomedical field. The results proved these to be excellent materials with a lot of potential as adsorbents.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Quitosana/química , Liberação Controlada de Fármacos , Hidrogéis/química , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Metais , Polímeros/química , Poluentes Químicos da Água/química
13.
Molecules ; 27(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36235113

RESUMO

Synthesis and characterization of a novel and zwitterionic double squaraine dye (DSQ) with a unique D-A-A-D structure is being reported. Contrary to the conventional mono and bis-squaraine dyes with D-A-D and D-A-D-A molecular frameworks reported so far, DSQ dye demonstrated strong solvatochromism allowing for the multiple ion sensing using a single probe by judicious selection of the suitable solvent system. The DSQ dye exhibited a large solvatochromic shift of about 200 nm with color changes from the visible to NIR region with metal ion sensitivity. Utilization of a binary solvent consisted of dimethylformamide and acetonitrile (1:99, v/v), highly selective detection of Cu2+ ions with the linearity range from 50 µM to 1 nM and a detection limit of 6.5 × 10-10 M has been successfully demonstrated. Results of the Benesi-Hildebrand and Jobs plot analysis revealed that DSQ and Cu2+ ions interact in the 2:1 molecular stoichiometry with appreciably good association constant of 2.32 × 104 M-1. Considering the allowed limit of Cu2+ ions intake by human body as recommended by WHO to be 30 µM, the proposed dye can be conveniently used for the simple and naked eye colorimetric monitoring of the drinking water quality.


Assuntos
Água Potável , Corantes Fluorescentes , Acetonitrilas/análise , Cobre/análise , Ciclobutanos , Dimetilformamida , Água Potável/análise , Corantes Fluorescentes/química , Humanos , Íons/análise , Fenóis , Solventes/análise
14.
Physiol Mol Biol Plants ; 28(2): 363-381, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35400882

RESUMO

In the present study, green synthesis of zinc oxide nanoparticles (ZnO NP) using Eucalyptus lanceolatus (leaf litter) extract was explored after characterization with UV spectrophotometery, Fourier Transform Infrared analysis, X-ray diffraction and TEM studies. ZnO NPs stability was ensured with - 32.1 mV zeta potential, while TEM showed ZnO NP as hexagonal structure (100 nm). In vitro antimicrobial activity showed potential of ZnO NP against pathogens causing diseases in maize plants. Both in vitro and in vivo studies of ZnO NP and ZnSO4 (200 ppm and 400 ppm) over a two year period (2019, 2020) were conducted on Zea mays L. var. PG2458. ZnO NP seed priming improved seed vigor index, germination percentage, shoot and root length and fresh biomass. Foliar application improved stem diameter and leaf surface area. Physiological status was relatively better, while reproductive attributes got altered to guide resource allocation for better cob growth and biomass with ZnO NP. Leaf, cob, grain and total Zn was maximum for 200 ppm ZnO NP. Translocation of Zn from leaf to cob and cob to grain was faster for ZnO NP compared to ZnSO4. Higher concentration (400 ppm) of ZnO NPs and ZnSO4 proved phytotoxic for plant growth attributes. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01136-0.

15.
Physiol Mol Biol Plants ; 28(6): 1311-1321, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35910442

RESUMO

The phenotyping of plant roots is a challenging task and poses a major lacuna in plant root research. Roots rhizospheric zone is affected by several environmental cues among which salinity, drought, heavy metal and soil pH are key players. Among biological factors, fungal, nematode and bacterial interactions with roots are vital for improving nutrient uptake efficiency in plants. The subterranean nature of a plant root and the limited number of approaches for root phenotyping offers a great challenge to the plant breeders to select a desirable root trait under different stress conditions. Identification of key root traits can provide a basic understanding for generating crop plants with enhanced ability to withstand various biotic or abiotic stresses. For instance, crops with improved soil exploration potential, phosphate uptake efficiency, water use efficiency and others. Laboratory methods such as hydroponics, rhizotron, rhizoslide and luminescence observatory for roots do not provide precise and desired root quantification attributes. Though 3D imaging by X-ray computed tomography (X-ray-CT) and magnetic resonance imaging techniques are complex, however, it provides the most applicable and practically relevant data for quantifying root system architecture traits. This review outlines the current developments in root studies including recent approaches viz. X-ray-CT, MRI, thermal infrared imaging and minirhizotron. Although root phenotyping is a laborious procedure, it offers multiple advantages by removing discrepancies and providing the actual practical significance of plant roots for breeding programs.

16.
Angew Chem Int Ed Engl ; 61(7): e202110990, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34841648

RESUMO

The mechanism of separation methods, for example, liquid chromatography, is realized through rapid multiple adsorption-desorption steps leading to the dynamic equilibrium state in a mixture of molecules with different partition coefficients. Sorting of colloidal particles, including protein complexes, cells, and viruses, is limited due to a high energy barrier, up to millions kT, required to detach particles from the interface, which is in dramatic contrast to a few kT for small molecules. Such a strong interaction renders particle adsorption quasi-irreversible. The dynamic adsorption-desorption equilibrium is approached very slowly, if ever attainable. This limitation is alleviated with a local oscillating repulsive mechanical force generated at the microstructured stimuli-responsive polymer interface to switch between adsorption and mechanical-force-facilitated desorption of the particles. Such a dynamic regime enables the separation of colloidal mixtures based on the particle-polymer interface affinity, and it could find use in research, diagnostics, and industrial-scale label-free sorting of highly asymmetric mixtures of colloids and cells.


Assuntos
Polímeros/química , Adsorção , Coloides/química , Tamanho da Partícula
17.
J Natl Compr Canc Netw ; 19(11): 1258-1263, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325401

RESUMO

BACKGROUND: Editorials accompanying the publication of trials in major oncology journals can have a substantial influence on clinical practice. We describe the prevalence of financial conflicts of interest (FCOIs) of authors writing such editorials and the extent to which FCOIs may shape the interpretation of clinical trials. METHODS: We examined editorials published in 2018 alongside trial reports in the top 5 journals that publish cancer drug trials (New England Journal of Medicine, Lancet, Lancet Oncology, JAMA Oncology, and Journal of Clinical Oncology). An editorial was considered to have an FCOI if at least one of the editorialists had any disclosed FCOI. An FCOI with the same company whose drug was being discussed in the editorial was classified as a direct FCOI. Editorials were reviewed for their content and classified as being unduly favorable (defined as the presence of a positive spin without discussion of limitations) or not. Association of an FCOI and a direct FCOI with writing an unduly favorable editorial was assessed. RESULTS: Of the 90 editorials assessed, 74% (n=67) were classified as having an FCOI with the pharmaceutical industry, and 39% (n=35) had an FCOI with the same company whose product was being discussed in the editorial (direct FCOI). Editorials were classified as being unduly favorable toward the study drug in 12% (8 of 67) and 13% (3 of 23) (P=1.0) of those with and without FCOIs, respectively; corresponding rates with and without direct FCOI were 23% (8 of 35) and 5% (3 of 55), respectively (P=.009). CONCLUSIONS: Editorials in top oncology journals were frequently authored by experts with FCOIs, including direct FCOIs. Authoring an unduly favorable editorial for a new cancer drug was significantly associated with the author having a direct FCOI with the same company. These findings support the call for journals to ensure that authors of editorials have no direct FCOIs.

18.
Inflammopharmacology ; 29(4): 1001-1016, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34110533

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) known as coronavirus disease (COVID-19), emerged in Wuhan, China, in December 2019. On March 11, 2020, it was declared a global pandemic. As the world grapples with COVID-19 and the paucity of clinically meaningful therapies, attention has been shifted to modalities that may aid in immune system strengthening. Taking into consideration that the COVID-19 infection strongly affects the immune system via multiple inflammatory responses, pharmaceutical companies are working to develop targeted drugs and vaccines against SARS-CoV-2 COVID-19. A balanced nutritional diet may play an essential role in maintaining general wellbeing by controlling chronic infectious diseases. A balanced diet including vitamin A, B, C, D, E, and K, and some micronutrients such as zinc, sodium, potassium, calcium, chloride, and phosphorus may be beneficial in various infectious diseases. This study aimed to discuss and present recent data regarding the role of vitamins and minerals in the treatment of COVID-19. A deficiency of these vitamins and minerals in the plasma concentration may lead to a reduction in the good performance of the immune system, which is one of the constituents that lead to a poor immune state. This is a narrative review concerning the features of the COVID-19 and data related to the usage of vitamins and minerals as preventive measures to decrease the morbidity and mortality rate in patients with COVID-19.


Assuntos
COVID-19/imunologia , COVID-19/prevenção & controle , Suplementos Nutricionais , Sistema Imunitário/imunologia , Micronutrientes/administração & dosagem , Minerais/administração & dosagem , Vitaminas/administração & dosagem , Humanos , Sistema Imunitário/efeitos dos fármacos
19.
J Am Chem Soc ; 142(45): 19209-19216, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33124818

RESUMO

Tuning the performance of nanoparticle (NP) catalysts by controlling the NP surface strain has evolved as an important strategy to optimize NP catalysis in many energy conversion reactions. Here, we present our new study on using an eigenforce model to predict and experiments to verify the strain-induced catalysis enhancement of the oxygen reduction reaction (ORR) in the presence of L10-CoMPt NPs (M = Mn, Fe, Ni, Cu, Ni). The eigenforce model allowed us to predict anisotropic (that is, two-dimensional) strain levels on distorted Pt(111) surfaces. Experimentally, by preparing a series of 5 nm L10-CoMPt NPs, we could push the ORR catalytic activity of these NPs toward the optimum region of the theoretical two-dimensional volcano plot predicted for L10-CoMPt. The best ORR catalyst in the alloy NP series we studied is L10-CoNiPt, which has a mass activity of 3.1 A/mgPt and a specific activity of 9.3 mA/cm2 at room temperature with only 15.9% loss of mass activity after 30 000 cycles at 60 °C in 0.1 M HClO4.


Assuntos
Nanopartículas Metálicas/química , Oxigênio/química , Ligas/química , Catálise , Teoria da Densidade Funcional , Oxirredução
20.
Sensors (Basel) ; 21(1)2020 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-33375340

RESUMO

The complex structure of turning aggravates obtaining the desired results in terms of tool wear and surface roughness. The existence of high temperature and pressure make difficult to reach and observe the cutting area. In-direct tool condition, monitoring systems provide tracking the condition of cutting tool via several released or converted energy types, namely, heat, acoustic emission, vibration, cutting forces and motor current. Tool wear inevitably progresses during metal cutting and has a relationship with these energy types. Indirect tool condition monitoring systems use sensors situated around the cutting area to state the wear condition of the cutting tool without intervention to cutting zone. In this study, sensors mostly used in indirect tool condition monitoring systems and their correlations between tool wear are reviewed to summarize the literature survey in this field for the last two decades. The reviews about tool condition monitoring systems in turning are very limited, and relationship between measured variables such as tool wear and vibration require a detailed analysis. In this work, the main aim is to discuss the effect of sensorial data on tool wear by considering previous published papers. As a computer aided electronic and mechanical support system, tool condition monitoring paves the way for machining industry and the future and development of Industry 4.0.

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