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1.
J Chem Phys ; 160(12)2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38516978

ABSTRACT

Chiral molecules can exhibit strong spin-orbit coupling, which can result in a large spin polarization. This is due to the fact that the energy levels of the electrons in a chiral molecule are strongly influenced by the chiral structure of the molecule, which can result in the separation of the energy levels for electrons with different spin orientations. We report a controlled spin-selective transmission of electrons through 20 base-paired poly-cytosine molecules functionalized with MoS2 flakes on ITO glass via the quantum mechanical tunneling effect. A reversion in spin polarization was observed after the silver ions interact with poly-cytosine due to the strong coordination of Ag(I) with cytosine-cytosine (C-C) mismatches, indicating the formation of duplex structural motifs, as confirmed by the circular dichroism spectroscopy at room temperature. Manipulating the spin of an electron through such a small molecule merely controlled by special cations could pave the way for major advances in spin-independent charge transport, advanced bioanalytical system design, and related applications.

2.
Environ Res ; 250: 118519, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38382660

ABSTRACT

The present study explores visible light-assisted photodegradation of ciprofloxacin hydrochloride (CIP) antibiotic as a promising solution to water pollution. The focus is on transforming the optical and electronic properties of BiOCl through the generation of oxygen vacancies (OVs) and the exposure of (110) facets, forming a robust S-scheme heterojunction with WS2. The resultant OVs mediated composite with an optimal ratio of WS2 and BiOCl-OV (4-WS2/BiOCl-OV) demonstrated remarkable efficiency (94.3%) in the visible light-assisted photodegradation of CIP antibiotic within 1.5 h. The CIP degradation using 4-WS2/BiOCl-OV followed pseudo-first-order kinetics with the rate constant of 0.023 min-1, outperforming bare WS2, BiOCl, and BiOCl-OV by 8, 6, and 4 times, respectively. Density functional theory (DFT) analysis aligned well with experimental results, providing insights into the structural arrangement and bandgap analysis of the photocatalysts. Liquid chromatography-mass spectrometry (LC-MS) analysis utilized for identifying potentially degraded products while scavenging experiments and electron paramagnetic resonance (EPR) spin trapping analysis elucidated the S-scheme charge transfer mechanism. This research contributes to advancing the design of oxygen vacancy-mediated S-scheme systems in the realm of photocatalysis, with potential implications for addressing water pollution concerns.


Subject(s)
Ciprofloxacin , Oxygen , Photolysis , Wastewater , Water Pollutants, Chemical , Ciprofloxacin/chemistry , Water Pollutants, Chemical/chemistry , Wastewater/chemistry , Oxygen/chemistry , Bismuth/chemistry , Anti-Bacterial Agents/chemistry , Tungsten/chemistry , Catalysis , Light , Density Functional Theory
3.
J Chem Phys ; 159(11)2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37712794

ABSTRACT

Mastering the manipulation of the electron spin plays a crucial role in comprehending the behavior of organic materials in several applications, such as asymmetric catalysis, chiroptical switches, and electronic devices. A promising avenue for achieving such precise control lies in the Chiral Induced Spin Selectivity (CISS) effect, where electrons with a favored spin exhibit preferential transport through chiral assemblies of specific handedness. Chiral supramolecular polymers emerge as excellent candidates for exploring the CISS effect due to their ability to modulate their helical structure through noncovalent interactions. In this context, systems capable of responding to external stimuli are particularly intriguing, sometimes even displaying chirality inversion. This study unveils spin selectivity in chiral supramolecular polymers, derived from single enantiomers, through scanning tunneling microscopy conducted in scanning tunneling spectroscopy mode. Following two distinct sample preparation protocols for each enantiomer, we generate supramolecular polymers with opposite handedness and specific spin transport characteristics. Our primary focus centers on chiral π-conjugated building blocks, with the aim of advancing novel systems that can inspire the organic spintronics community from a supramolecular chemistry level.

4.
Pediatr Pulmonol ; 58(9): 2663-2665, 2023 09.
Article in English | MEDLINE | ID: mdl-37278554

ABSTRACT

A 6-month-old infant with recurrent respiratory infections, rapid breathing, and reduced air entry on the right side was diagnosed with congenital bronchopulmonary foregut malformation (CBPFM). Imaging revealed a collapsed and underdeveloped right lung, with the right bronchus appearing to originate from the lower part of the esophagus. An esophagogram confirmed the diagnosis by showing contrast flowing freely from the lower esophagus to the right bronchus.


Subject(s)
Pneumonia , Respiratory System Abnormalities , Infant , Humans , Lung/diagnostic imaging , Lung/abnormalities , Esophagus/diagnostic imaging , Pneumonia/complications , Pneumonia/diagnostic imaging , Bronchi/abnormalities , Trachea , Respiratory System Abnormalities/complications
5.
Environ Res ; 232: 116353, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37295591

ABSTRACT

Covalent organic frameworks (COFs) based on core@shell nanohybrids have recently received significant attention and have become one of the most promising strategies for improving the stability and catalytic activity of COFs. Compared with traditional core@shell, COF-based core@shell hybrids own remarkable advantages, including size-selective reactions, bifunctional catalysis, and integration of multiple functions. These properties could enhance the stability and recyclability, resistance to sintering, and maximize the electronic interaction between the core and the shell. The activity and selectivity of COF-based core@shell could be simultaneously improved by taking benefit of the existing synergy between the functional encapsulating shell and the covered core material. Considering that, we have highlighted various topological diagrams and the role of COFs in COF-based core@shell hybrid for activity and selectivity enhancement. This concept article provides all-inclusive advances in the design and catalytic applications of COF-based core@shell hybrids. Various synthetic techniques have been developed for the facile tailoring of functional core@shell hybrids, including novel seed growth, in-situ, layer-by-layer, and one-pot method. Importantly, charge dynamics and structure-performance relationships are investigated through different characterization techniques. Different COF-based core@shell hybrids with established synergistic interactions have been detailed, and their influence on stability and catalytic efficiency for various applications is explained and discussed in this contribution. A comprehensive discussion on the remaining challenges associated with COF-based core@shell nanoparticles and research directions has also been provided to deliver insightful ideas for additional future developments.


Subject(s)
Metal-Organic Frameworks , Nanoparticles , Nanostructures , Catalysis , Reproduction
6.
Environ Res ; 218: 114982, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36495966

ABSTRACT

Dual-pore covalent organic frameworks (COFs) offer a molecular scaffold for introducing building blocks into periodically organized polygonal skeletons to produce fascinating structural features. The rapid development of this material has attracted intensive interest from researchers with diverse expertise. This review selects the leading scientific findings about dual-pore COFs and highlights their functions and perspectives on design, structure properties, and synthesis strategies. Dual-pore COFs, as newly hetero-pore COFs by integrating particular pores into one polygonal skeleton, have been compared to conventional COFs. Dual-pore COFs display hierarchical/heterogeneous porosities and homogeneous porosity, which endow them with exceptional features involving mass diffusion, charge transfer, and large surface area with abundant active sites. Additionally, the strategic dual-pore design by opting for different approaches, such as integration of [D2h + C2] symmetries, kagome-type lattices, and other symmetric arrangements of monomers, are inclusively discussed. Identification and construction of dual-pores in COFs via optimal synthetic methods, such as desymmetrization, multiple linking sites, and orthogonal reactions, are highlighted as the primary pore engineering routes to simultaneously regulate the growth and alter the characteristics of COFs for promising applications. Lastly, a focused discussion on various challenges and critical fundamentals of dual-pore engineering is successfully outlined, with potential prospects of introducing dual-pore in COFs.


Subject(s)
Metal-Organic Frameworks , Diffusion , Porosity
7.
RSC Adv ; 12(22): 13609-13627, 2022 May 05.
Article in English | MEDLINE | ID: mdl-35530385

ABSTRACT

The selection of a facile, eco-friendly, and effective methodology is the need of the hour for efficient curing of the COVID-19 virus in air, water, and many food products. Recently, semiconductor-based photocatalytic methodologies have provided promising, green, and sustainable approaches to battle against viral activation via the oxidative capabilities of various photocatalysts with excellent performance under moderate conditions and negligible by-products generation as well. Considering this, recent advances in photocatalysis for combating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are inclusively highlighted. Starting from the origin to the introduction of the coronavirus, the significant potential of photocatalysis against viral prevention and -disinfection is discussed thoroughly. Various photocatalytic material-based systems including metal-oxides, metal-free and advanced 2D materials (MXenes, MOFs and COFs) are systematically examined to understand the mechanistic insights of virus-disinfection in the human body to fight against COVID-19 disease. Also, a roadmap toward sustainable solutions for ongoing COVID-19 contagion is also presented. Finally, the challenges in this field and future perspectives are comprehensively discussed involving the bottlenecks of current photocatalytic systems along with potential recommendations to deal with upcoming pandemic situations in the future.

8.
J Family Med Prim Care ; 11(4): 1497-1501, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35516694

ABSTRACT

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder which is a clinically heterogenous condition with a wide range of etiological factors and causing significant public health burden. If diagnosed at an earlier age, early interventions can be started this leads to functional outcome of children with ASD with respect to social, behavior and occupational sphere. Therefore, early detection and intervention are widely recommended in these children. So screening of toddlers who were identified to be "at risk" can be diagnosed using screening questionnaires by interviewing parents. Overall with this study we can conclude that, toddlers identified to be "at risk" and those diagnosed with ASD were not uncommon and M-CHAT-R is a useful screening test for the identification of "at risk" toddlers for Autism Spectrum Disorder in Jharkhand.

9.
J Environ Chem Eng ; 10(4): 107894, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35578627

ABSTRACT

The mass immunization is the prioritised post-pandemic phase offering preventive countermeasure for COVID-19 pandemic. However, it is crucial to tackle the environmental impact of COVID-19 vaccine waste for sustainable vaccination management because a prolonged immunisation campaign is expected. As the pace of vaccine production, distribution and mass vaccination has been expedited, there is a simultaneous rise in plastic derived vaccine waste including syringes, needles, used/unused vaccine vials, vaccine packaging, and protective gear (surgical facemasks, gloves, face shields, etc). Henceforth, in view of the repercussions of heaping plastic waste in the environment, this article provides a perspective on the usage of synthetic and natural materials as potential substituents for vaccination tools. The biodegradable polymeric gums such as cellulose, gellan, pectin, etc. have been successfully applied for the fabrication of surgical facemasks. The highly suggestive practice is replacement of conventional polypropylene based plastics with bioplastics or paper for vaccine packaging. The usage of biodegradable bio-plastics as packaging material along with environmentally friendly face masks can help to achieve the zero waste approach. The discussion in the article significantly highlights the necessity of opting sustainable solutions of disinfecting and substituting vaccination tools for an environment friendly ongoing vaccination campaign.

10.
J Environ Chem Eng ; 10(3): 107527, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35280853

ABSTRACT

Coronavirus disease-2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been one of the most challenging worldwide epidemics of recent times. Semiconducting materials (photocatalysts) could prove effectual solar-light-driven technology on account of variant reactive oxidative species (ROS), including superoxide (•O2 - ) and hydroxyl (•OH) radicals either by degradation of proteins, DNA, RNA, or preventing cell development by terminating cellular membrane. Graphene-based materials have been exquisitely explored for antiviral applications due to their extraordinary physicochemical features including large specific surface area, robust mechanical strength, tunable structural features, and high electrical conductivity. Considering that, the present study highlights a perspective on the potentials of graphene based materials for photocatalytic antiviral activity. The interaction of virus with the surface of graphene based nanomaterials and the consequent physical, as well as ROS induced inactivation process, has been highlighted and discussed. It is highly anticipated that the present review article emphasizing mechanistic antiviral insights could accelerate further research in this field.

11.
Environ Res ; 209: 112814, 2022 06.
Article in English | MEDLINE | ID: mdl-35090874

ABSTRACT

The prevalence of global health implications from the COVID-19 pandemic necessitates the innovation and large-scale application of disinfection technologies for contaminated surfaces, air, and wastewater as the significant transmission media of disease. To date, primarily recommended disinfection practices are energy exhausting, chemical driven, and cause severe impact on the environment. The research on advanced oxidation processes has been recognized as promising strategies for disinfection purposes. In particular, semiconductor-based photocatalysis is an effective renewable solar-driven technology that relies on the reactive oxidative species, mainly hydroxyl (•OH) and superoxide (•O2-) radicals, for rupturing the capsid shell of the virus and loss of pathogenicity. However, the limited understanding of critical aspects such as viral photo-inactivation mechanism, rapid virus mutagenicity, and virus viability for a prolonged time restricts the large-scale application of photocatalytic disinfection technology. In this work, fundamentals of photocatalysis disinfection phenomena are addressed with a reviewed remark on the reported literature of semiconductor photocatalysts efficacies against SARS-CoV-2. Furthermore, to validate the photocatalysis process on an industrial scale, we provide updated data on available commercial modalities for an effective virus photo-inactivation process. An elaborative discussion on the long-term challenges and sustainable solutions is suggested to fill in the existing knowledge gaps. We anticipate this review will ignite interest among researchers to pave the way to the photocatalysis process for disinfecting virus-contaminated environments and surfaces for current and future pandemics.


Subject(s)
COVID-19 , Disinfection , COVID-19/prevention & control , Humans , Pandemics/prevention & control , SARS-CoV-2 , Wastewater
12.
Sci Total Environ ; 806(Pt 1): 150349, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-34555610

ABSTRACT

The global outburst of coronavirus 2019 (COVID-19) has posed severe challenges to human health, environment, energy and economy all over the world. The stringent measures to control the spread of COVID-19 results a significant slowdown in economic activities which in turn affected the environment by reducing the greenhouse gas (GHG) emissions, specifically lower atmospheric CO2 levels. Considering that, the present study intends to highlight the substantial impact of COVID-19 pandemic on GHG emissions, by systematically reviewing the available scientific literatures. The study further outlined the variation in GHG emissions by comparing the data focused on pre-pandemic, during pandemic, and post-pandemic (predictions) scenarios. Further, the assessment on elevating CO2 levels, global economic, and energy impacts of COVID-19 has also been reviewed. Also, the possible recovery plan for the framework of sustainable environmental and energy development is presented. Finally, the review concludes with an insightful summary involving the challenges and future outlook towards sustainable development goals in a hope that the present study can help the researchers to assess the global environmental and energy related consequences.


Subject(s)
COVID-19 , Greenhouse Gases , Carbon Dioxide/analysis , Greenhouse Effect , Greenhouse Gases/analysis , Humans , Pandemics , SARS-CoV-2
13.
Sci Total Environ ; 800: 149410, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34391150

ABSTRACT

Oxygen vacancy as a typical point defect has incited substantial interest in photocatalysis due to its profound impact on optical absorption response and facile isolation of photocarriers. The presence of oxygen vacancy can introduce the midgap defect states, which promote extended absorption in the visible region. The redistribution of electron density at the surface can stimulate the adsorption and activation kinetics of adsorbates, manifesting optimal photocatalytic performance. Despite such alluring outcomes, the ambiguity in understanding the precise location, appropriate concentration, and oxygen vacancy role is still a long-standing task. The present review article comprehensively outlines the identification of oxygen vacancy defects at bulk or on the surface and its ultimate effect on the photocatalytic degradation of phenolic compounds. Particular emphasis has been drawn to summarize the critical influence of oxygen vacancy on different factors such as crystal structure, bandgap energy, electronic structure, and charge carrier mobility by integrating experimental results and theoretical calculations. We have also explored the reaction pathways and the intermediate chemistry of phenol photodegradation by analyzing the molecular activation (O2, H2O, and sulphate activation) through oxygen vacancy defects. Finally, the review concludes with the various challenges and future perspectives, aiming to provide a firm base for further progressions towards photocatalysis.


Subject(s)
Nanostructures , Oxygen , Phenols , Photolysis
14.
Abdom Radiol (NY) ; 46(8): 3917-3926, 2021 08.
Article in English | MEDLINE | ID: mdl-33782739

ABSTRACT

PURPOSE: To evaluate role of 3-T magnetic resonance portovenography (MRPV) in children with extra hepatic portal venous obstruction (EHPVO) and compare unenhanced and contrast-enhanced sequences. METHODS: 20 Children with EHPVO underwent MRPV using unenhanced [T2, T1 pre-contrast, Balanced turbo field echo (BTFE)] and contrast-enhanced (CE) modified DIXON (mDIXON) sequences. The images were evaluated for the patency of abdominal veins, hepatic and splenic parenchyma by two radiologists for interobserver agreement. RESULTS: BTFE and post-contrast mDIXON sequences performed best for evaluation of abdominal veins. Concordance between the BTFE and CE sequences was good to very good for both the radiologists for splenic vein (SV) evaluation. The concordance between the two sequences for evaluation of superior mesenteric vein and its confluence with the SV was less remarkable and varied from fair to good, while the interobserver agreement was very good to perfect. The interobserver agreement between the BTFE and CE sequence for the evaluation of left renal vein was very good, while that for IVC was perfect. The agreement between BTFE and CE sequence was perfect for the evaluation of right and middle hepatic veins, while the interobserver agreement was good to perfect. The interobserver agreement was poor for evaluation of hepatic parenchyma on BTFE sequence as compared to CE sequence, and moderate for splenic parenchyma. CONCLUSION: BTFE sequence is the single best unenhanced MR pulse sequence to detect all the vascular structures in children with EHPVO. CE-MRI is not superior to BTFE sequence and should be used at the discretion of the radiologist.


Subject(s)
Magnetic Resonance Imaging , Portal Vein , Abdomen , Child , Contrast Media , Humans , Magnetic Resonance Spectroscopy , Portal Vein/diagnostic imaging
15.
Plant Signal Behav ; 15(8): 1709707, 2020 08 02.
Article in English | MEDLINE | ID: mdl-31906799

ABSTRACT

Alpha-galactosides or Raffinose Family Oligosaccharides (RFOs) are enriched in legumes and are considered as anti-nutritional factors responsible for inducing flatulence. Due to a lack of alpha-galactosidases in the stomachs of humans and other monogastric animals, these RFOs are not metabolized and are passed to the intestines to be processed by gut bacteria leading to distressing flatulence. In plants, alpha(α)-galactosides are involved in desiccation tolerance during seed maturation and act as a source of stored energy utilized by germinating seeds. The hydrolytic enzyme alpha-galactosidase (α-GAL) can break down RFOs into sucrose and galactose releasing the monosaccharide α-galactose back into the system. Through characterization of RFOs, sucrose, reducing sugars, and α-GAL activity in maturing and germinating chickpeas, we show that stored RFOs are likely required to maintain a steady-state level of reducing sugars. These reducing sugars can then be readily converted to generate energy required for the high energy-demanding germination process. Our observations indicate that RFO levels are lowest in imbibed seeds and rapidly increase post-imbibition. Both RFOs and the α-GAL activity are possibly required to maintain a steady-state level of the reducing monosaccharide sugars, starting from dry seeds all the way through post-germination, to provide the energy for increased germination vigor.


Subject(s)
Cicer/enzymology , Cicer/metabolism , Oligosaccharides/metabolism , Raffinose/metabolism , Seeds/metabolism , alpha-Galactosidase/metabolism , Germination/physiology , Sucrose/metabolism
16.
Int J Mol Sci ; 18(4)2017 Apr 24.
Article in English | MEDLINE | ID: mdl-28441779

ABSTRACT

The ubiquitous glyoxalase enzymatic pathway is involved in the detoxification of methylglyoxal (MG), a cytotoxic byproduct of glycolysis. The glyoxalase system has been more extensively studied in animals versus plants. Plant glyoxalases have been primarily associated with stress responses and their overexpression is known to impart tolerance to various abiotic stresses. In plants, glyoxalases exist as multigene families, and new roles for glyoxalases in various developmental and signaling pathways have started to emerge. Glyoxalase-based MG detoxification has now been shown to be important for pollination responses. During self-incompatibility response in Brassicaceae, MG is required to target compatibility factors for proteasomal degradation, while accumulation of glyoxalase leads to MG detoxification and efficient pollination. In this review, we discuss the importance of glyoxalase systems and their emerging biological roles in plants.


Subject(s)
Aldehyde Oxidoreductases/metabolism , Lactoylglutathione Lyase/metabolism , Plant Proteins/metabolism , Plants/enzymology , Thiolester Hydrolases/metabolism , Pollination/physiology , Pyruvaldehyde/metabolism , Signal Transduction , Stress, Physiological
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