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1.
Int J Pharm ; 658: 124212, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38723730

RESUMO

Liposomes are nanosized, spherical vesicles consisting of an aqueous core encircled by one or more phospholipid bilayer shells. Liposomes have found extensive use in numerous biomedicine and nanomedicine applications due to their excellent biocompatibility, adaptable chemical composition, ease of preparation, and diverse structural characteristics. These applications include nanocarriers for drug delivery, immunoassays, nutraceuticals, tissue engineering, clinical diagnostics, and theranostics formulations. These applications stimulated significant efforts toward scaling up formation processes in anticipation of appropriate industrial advancement. Despite the advancements in conventional methods and the emergence of new approaches for liposome production, their inherent susceptibility to chemical and mechanical influences contributes to critical challenges, including limited colloidal stability and decreased efficiency in encapsulating cargo molecules. With this context, the current review provides brief insights into liposomes conventional and novel industrial production techniques. With a special focus on the structural parameters, and pivotal elements influencing the synthesis of an appropriate and stable formulation, followed by the various regulatory aspects of industrial production.

2.
Arch Microbiol ; 206(5): 205, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573383

RESUMO

Honeybees are vital for global crop pollination, making indispensable contributions to agricultural productivity. However, these vital insects are currently facing escalating colony losses on a global scale, primarily attributed to parasitic and pathogenic attacks. The prevalent response to combat these infections may involve the use of antibiotics. Nevertheless, the application of antibiotics raises concerns regarding potential adverse effects such as antibiotic resistance and imbalances in the gut microbiota of bees. In response to these challenges, this study reviews the utilization of a probiotic-supplemented pollen substitute diet to promote honeybee gut health, enhance immunity, and overall well-being. We systematically explore various probiotic strains and their impacts on critical parameters, including survival rate, colony strength, honey and royal jelly production, and the immune response of bees. By doing so, we emphasize the significance of maintaining a balanced gut microbial community in honeybees. The review also scrutinizes the factors influencing the gut microbial communities of bees, elucidates the consequences of dysbiosis, and evaluates the potential of probiotics to mitigate these challenges. Additionally, it delineates different delivery mechanisms for probiotic supplementation and elucidates their positive effects on diverse health parameters of honeybees. Given the alarming decline in honeybee populations and the consequential threat to global food security, this study provides valuable insights into sustainable practices aimed at supporting honeybee populations and enhancing agricultural productivity.


Assuntos
Criação de Abelhas , Probióticos , Abelhas , Animais , Agricultura , Antibacterianos , Disbiose
3.
Waste Manag ; 182: 164-174, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38653044

RESUMO

The current study introduces an innovative methodology by utilizing treated wastewater (TWW) from an effluent treatment plant as a washing agent to enhance the characteristics of incineration bottom ash (IBA). This approach addresses sustainability concerns and promotes the circular economy by reusing wastewater generated in municipal solid waste incineration facilities. Previous research has underscored the challenges of open IBA reuse due to elevated leaching of chlorides, sulfates, and trace metal(loid)s. Thus, the experimental setup explores various combinations of washing, with or without screening, to optimize the properties of soil-like material (SLM < 4.75 mm) and overall material (OM < 31.5 mm) fractions of IBA for unrestricted applications. Batch leaching tests were conducted on treated samples, and leaching characteristics were evaluated in accordance with regulatory standards, primarily the Dutch standard for unrestricted IBA reuse. The findings reveal that washing in isolation proves insufficient to enhance IBA properties; however, washing followed by screening, specifically for removing fines (<0.15 mm), proves effective in reducing contamination. The study identifies that multiple steps of washing and screening (with recirculation) process render OM and SLM fractions suitable for unrestricted reuse with a cumulative liquid-to-solid ratio of 6 L/kg and a total washing time of 15 min. The multi-step treatment was found effective in reducing sulfate contamination by 65-74 % and chloride contamination by 83-89 % in IBA fractions. This approach offers a promising solution for overcoming the limitations associated with IBA leaching, thereby promoting sustainable waste reuse practices.


Assuntos
Incineração , Águas Residuárias , Incineração/métodos , Águas Residuárias/química , Resíduos Sólidos/análise , Reciclagem/métodos , Cinza de Carvão/análise , Cinza de Carvão/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise
4.
Nano Lett ; 24(18): 5413-5419, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38669591

RESUMO

Motional narrowing implies narrowing induced by motion; for example, in nuclear magnetic resonance, the thermally induced random motion of the nuclei in an inhomogeneous environment leads to a counterintuitive narrowing of the resonance line. Similarly, the excitons in monolayer semiconductors experience magnetic inhomogeneity: the electron-hole spin-exchange interaction manifests as an in-plane pseudomagnetic field with a periodically varying orientation inside the exciton band. The excitons undergo random momentum scattering and pseudospin precession repeatedly in this inhomogeneous magnetic environment, typically resulting in fast exciton depolarization. On the contrary, we show that such magnetic inhomogeneity averages out at high scattering rates due to motional narrowing. Physically, a faster exciton scattering leads to a narrower pseudospin distribution on the Bloch sphere, implying a nontrivial improvement in exciton polarization. The in-plane nature of the pseudomagnetic field enforces a contrasting scattering dependence between the circularly and linearly polarized excitons, providing a spectroscopic way to gauge the sample quality.

5.
Prog Mol Biol Transl Sci ; 204: 219-248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38458739

RESUMO

RNA therapeutics have emerged as potential treatments for genetic disorders, infectious diseases, and cancer. RNA delivery to target cells for efficient therapeutic applications remains challenging due to instability and poor uptake. Polymeric nanoparticulate delivery systems offer stability, protection, and controlled release. These systems shield RNA from degradation, enabling efficient uptake and extended circulation. Various polymeric nanoparticle platforms have been explored, including lipid-based nanoparticles, polymeric micelles, dendrimers, and polymer-drug conjugates. This review outlines recent breakthroughs of recent advances, design principles, characterization techniques, and performance evaluation of these delivery systems. It highlights their potential in translating preclinical studies into clinical applications. Additionally, the review discusses the application of polymeric nanoparticles in ophthalmic drug delivery, particularly for medications that dissolve poorly in water, and the progress made in siRNA-based therapies for viral infections, autoimmune diseases, and cancers. SiRNA holds great promise for precision medicine and therapeutic intervention, with the ability to target specific genes and modulate disease-associated pathways. The versatility and potency of siRNA-based drugs offer a broader scope for therapeutic intervention compared to traditional biological drugs. As research in RNA therapeutics continues to advance, these technologies hold tremendous potential to revolutionize the treatment of various diseases and improve patient outcomes.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/terapia , Sistemas de Liberação de Medicamentos , RNA Interferente Pequeno/uso terapêutico , RNA Interferente Pequeno/genética , Polímeros
6.
Front Microbiol ; 15: 1355750, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468848

RESUMO

Numerous bacterial species associate with plants through commensal, mutualistic, or parasitic association, affecting host physiology and health. The mechanism for such association is intricate and involves the secretion of multiple biochemical substances through dedicated protein systems called secretion systems SS. Eleven SS pathways deliver protein factors and enzymes in their immediate environment or host cells, as well as in competing microbial cells in a contact-dependent or independent fashion. These SS are instrumental in competition, initiation of infection, colonization, and establishment of association (positive or negative) with host organisms. The role of SS in infection and pathogenesis has been demonstrated for several phytopathogens, including Agrobacterium, Xanthomonas, Ralstonia, and Pseudomonas. Since there is overlap in mechanisms of establishing association with host plants, several studies have investigated the role of SSs in the interaction of plant and beneficial bacteria, including symbiotic rhizobia and plant growth bacteria (PGPB). Therefore, the present review updates the role of different SSs required for the colonization of beneficial bacteria such as rhizobia, Burkholderia, Pseudomonas, Herbaspirillum, etc., on or inside plants, which can lead to a long-term association. Most SS like T3SS, T4SS, T5SS, and T6SS are required for the antagonistic activity needed to prevent competing microbes, including phytopathogens, ameliorate biotic stress in plants, and produce substances for successful colonization. Others are required for chemotaxis, adherence, niche formation, and suppression of immune response to establish mutualistic association with host plants.

7.
Clin Case Rep ; 12(2): e8361, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38314184

RESUMO

Monoclonal gammopathy of uncertain significance associated acquired von Willebrand syndrome is a serious bleeding condition driven by immunological clearance of von Willebrand factor and has limited treatment options. We present a patient who achieved durable remission through eradication of the monoclonal paraprotein with clonal directed therapy with bortezomib.

8.
Int J Pharm ; 652: 123808, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38224758

RESUMO

The malignancy of the prostate is a complicated ailment which impacts millions of male populations around the globe. Despite the multitude of endeavour accomplished within this domain, modalities that are involved in the ameliorative management of predisposed infirmity are still relent upon non-specific and invasive procedures, thus imposing a detrimental mark on the living standard of the individual. Also, the orchestrated therapeutic interventions are still incompetent in substantiating a robust and unabridged therapeutic end point owing to their inadequate solubility, low bioavailability, limited cell assimilation, and swift deterioration, thereby muffling the clinical application of these existing treatment modalities. Nanotechnology has been employed in an array of modalities for the medical management of malignancies. Among the assortment of available nano-scaffolds, nanocarriers composed of a bio-decomposable and hybrid polymeric material like PLGA hold an opportunity to advance as standard chemotherapeutic modalities. PLGA-based nanocarriers have the prospect to address the drawbacks associated with conventional cancer interventions, owing to their versatility, durability, nontoxic nature, and their ability to facilitate prolonged drug release. This review intends to describe the plethora of evidence-based studies performed to validate the applicability of PLGA nanosystem in the amelioration of prostate malignancies, in conjunction with PLGA focused nano-scaffold in the clinical management of prostate carcinoma. This review seeks to explore numerous evidence-based studies confirming the applicability of PLGA nanosystems in ameliorating prostate malignancies. It also delves into the role of PLGA-focused nano-scaffolds in the clinical management of prostate carcinoma, aiming to provide a comprehensive perspective on these advancements.


Assuntos
Carcinoma , Neoplasias da Próstata , Masculino , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Neoplasias da Próstata/tratamento farmacológico , Polímeros , Nanotecnologia
9.
Curr Aging Sci ; 16(3): 240-247, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638589

RESUMO

BACKGROUND: Increasing age and the added disadvantage of diabetic peripheral neuropathy (DPN) put the individual at a higher risk of falls and reduced functional fitness. However, there is a dearth of literature on multifactorial balance intervention, especially targeting the needs of older adults with DPN. OBJECTIVE: The current study aimed to determine the effect of a multifactorial balance rehabilitation program on fall risk and functional fitness in older adults with DPN. METHODS: In this pre-post experimental study, 30 independently ambulating older adults (71.2 ± 4.70 years) with DPN, who were at risk of falling (timed up and go score ≥ 9.4 seconds), were recruited. Along with the standard care, all the participants received 12 weeks of the multifactorial balance rehabilitation program. RESULTS: Fall risk using the Fullerton Advanced Balance scale and functional fitness using the Senior Fitness Test were measured at baseline and after 12 weeks of the intervention. The intervention reduced the risk of falling score significantly (MD = 6.17, p < .001). All six parameters of functional fitness improved after 12 weeks of intervention. The improvement in lower limb strength (MD = 1.53 times), upper limb strength (MD = 2.48 times), endurance (MD = 16.07 seconds), lower limb flexibility (MD = 2.02 inches), upper limb flexibility (MD = 1.47 inches), and dynamic balance (MD = 1.53 seconds) was statistically significant at p < 0.05. CONCLUSION: This study provided encouraging evidence about the potential of multifactorial balance rehabilitation to reduce the risk of falling and improve functional fitness in older adults with DPN.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Humanos , Idoso , Acidentes por Quedas/prevenção & controle , Neuropatias Diabéticas/diagnóstico , Exercício Físico , Estado Nutricional
10.
Light Sci Appl ; 12(1): 173, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443142

RESUMO

In monolayer transition metal dichalcogenide semiconductors, valley coherence degrades rapidly due to a combination of fast scattering and inter-valley exchange interaction. This leads to a sub-picosecond valley coherence time, making coherent manipulation of exciton a highly challenging task. Using monolayer MoS2 sandwiched between top and bottom graphene, here we demonstrate fully valley-coherent excitons by observing ~100% degree of linear polarization in steady state photoluminescence. This is achieved in this unique design through a combined effect of (a) suppression in exchange interaction due to enhanced dielectric screening, (b) reduction in exciton lifetime due to a fast inter-layer transfer to graphene, and (c) operating in the motional narrowing regime. We disentangle the role of the key parameters affecting valley coherence by using a combination of calculation (solutions of Bethe-Salpeter and Maialle-Silva-Sham equations) and a careful choice of design of experiments using four different stacks with systematic variation of screening and exciton lifetime. To the best of our knowledge, this is the first report in which the excitons are found to be valley coherent in the entire lifetime in monolayer semiconductors, allowing optical readout of valley coherence possible.

11.
Afr J Paediatr Surg ; 20(3): 218-223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37470559

RESUMO

Background: Pyogenic liver abscess (LA) is a significant contributor to morbidity and mortality in developing countries like India. The risk factors predisposing to the LA specifically in children are not known. Studies done in the past largely remain inconclusive and have identified only probable causes. The cause of LA in children with no coexisting illness remains unknown. Methodology: This prospective observational study was conducted at a tertiary teaching hospital located in New Delhi, India. All children between 2 months and 12 years of age with sonographically confirmed LA presenting to the hospital were included and managed with appropriate intravenous antibiotics and relevant investigations. Results: A total of 52 children were included. The mean age was 6 years and 4 months, and the male: female ratio was 1.4:1. Around 50% of the patients were malnourished. Fever, abdominal pain and loss of appetite were the most common symptoms. Nine patients (17%) were managed conservatively, 13 (25%) needed percutaneous needle aspiration and 30 (57.69%) required drainage using a pigtail catheter. Poor socioeconomic status and anaemia were found to be the most commonly associated risk factors. Selective immunoglobulin A (IgA) deficiency was the most common primary immunodeficiency disorder followed by T-cell defect. On multivariate analysis, it was seen that in those with clinical icterus, gamma-glutamyl transferases >350 IU/m, and those with impending rupture, the time to defervescence was significantly different (P = 0.05). Conclusion: Poor socioeconomic status causing malnutrition emerged as a significant risk factor for LA in children. Selective IgA deficiency was the most common immunodeficiency seen in a few children. Adopting a conservative approach like aspiration and percutaneous drainage led to lower mortality and good recovery rates.


Assuntos
Abscesso Hepático Piogênico , Humanos , Masculino , Criança , Feminino , Abscesso Hepático Piogênico/terapia , Abscesso Hepático Piogênico/tratamento farmacológico , Drenagem , Antibacterianos/uso terapêutico , Fatores de Risco , Estudos Prospectivos
12.
Assay Drug Dev Technol ; 21(5): 190-201, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37285190

RESUMO

Ligand-receptor interactions (LRIs) are the basis for all the biological processes taking place in living cells and have been exploited to develop and implement in medical field a number of highly sensitive biosensors for the detection of various biomarkers in complex biological fluids. Drug-target interactions, one of the LRIs, are important to understand the biological processes that further help in developing new and better therapeutic molecules. Biosensors based on these interactions give us an idea for the need of modification of existing drugs or to develop new drugs. Common approach to develop biosensors requires the labeling; however, label-free systems provide advantages in avoiding the chances of conformational changes, off-site labeling, and labeling-based hindrances, thus saving time and effort toward assay development. Preliminary drug screening assays are carried out in two-dimensional (2D) models, followed by animal models, which require huge capital investment to reach from bench-top to clinical trials, where only 21% of new compounds make way to phase-1 clinical trials. Three-dimensional culture or organoid culture or organ-on-chip technology has made way for predictive and complex in vitro approach that recapitulates human physiology and represents more similar in vivo behavior than 2D. Multiplexing and nanotechnology have remarkably enhanced the efficacy of biosensors and might lead to a generation of miniaturized biosensors and more than just point-of-care kits. This review provides in-depth analysis of different types of biosensor assays based on drug-target interactions, their advantages, and limitations based on cost, sensitivity, and selectivity and industrial applications.


Assuntos
Técnicas Biossensoriais , Animais , Humanos , Ligantes , Técnicas Biossensoriais/métodos , Descoberta de Drogas , Nanotecnologia
13.
Waste Manag ; 168: 344-353, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37343441

RESUMO

The study presents the geoenvironmental and geotechnical characterization of MSW incineration bottom ash (IBA) and examines its reuse as structural fill in reinforced soil structures (RSS).The suitability of reuse has been assessed with regard to international regulatory standards. The prime focus of the work remains on evaluating the pullout response of geosynthetic reinforcements through IBA fill to determine the interaction coefficient, which has never been addressed in the literature. The economic viability of using IBA instead of locally available river sand for a 12 m high MSE wall is also established. The column leaching test results confirm that IBA can be utilized in RSS with suitable design measures. The geotechnical investigation shows that IBA is a well-graded, non-plastic lightweight material with adequate drainage and high shear strength. The pullout test results demonstrate that the interaction coefficient of polymeric strips and geogrid in IBA (0.73-1.53 and 0.79-1.91, respectively) is comparable or higher to materials conventionally used as structural fill in RSS, indicating adequate bondage between IBA and geosynthetic reinforcement. Further, it is estimated that using IBA as a substitute for available river sand in the vicinity can potentially reduce the overall RSS project cost by 15-20%, even if IBA has to be transported 50 km away from the project site.


Assuntos
Cinza de Carvão , Incineração , Cinza de Carvão/química , Solo , Areia , Resistência ao Cisalhamento , Resíduos Sólidos/análise
14.
J Bodyw Mov Ther ; 33: 39-45, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36775524

RESUMO

OBJECTIVE: To estimate self-reported musculoskeletal disorders among Indian population in work from home COVID-19 lockdown and its association on various socio-demographic and occupational factors among them. METHODS: The present cross-sectional study was conducted on working Indian professionals, through an online self-reported survey during the COVID-19 work from the home situation. Details about the perceived musculoskeletal discomforts, weight gain or loss, physical activity profile, number of working hours, total sedentary time, and satisfaction perceived with working from home were recorded from the participant responses and thereafter analyzed. RESULTS: A total of 281 responses were analyzed. 47.6% of respondents reported musculoskeletal disorders before lockdown, whereas 53.6% reported them during the lockdown period. 10% of respondents reported declination in physical activity. Finding of the chi-square for association and Spearman's rho correlation analysis suggested that gender, pre-existing musculoskeletal discomforts, current sedentary time, and long working hours are significantly associated with musculoskeletal discomforts during work from home COVID-19 lockdown. CONCLUSION: This study concluded the increment in the self-reported musculoskeletal disorders among working Indian professionals during work from home COVID-19 lockdown. The study also found the significant association between MSD and gender, working hours, sedentary time and pre-existing musculoskeletal discomforts.


Assuntos
COVID-19 , Doenças Musculoesqueléticas , Humanos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Estudos Transversais , Teletrabalho , Índia/epidemiologia , Doenças Musculoesqueléticas/epidemiologia
15.
Arch Pharm (Weinheim) ; 355(11): e2200081, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35924298

RESUMO

Fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) are the primary catabolic enzymes for endocannabinoids, anandamide (AEA), and 2-arachidonoyl glycerol. Numerous studies have shown that FAAH and MAGL play an important role in modulating various central nervous system activities; hence, the development of small molecule FAAH/MAGL inhibitors is an active area of research. Several small molecules possessing the carbamate scaffold are documented as potential FAAH/MAGL inhibitors. Here, we designed and synthesized a series of open chain and cyclic carbamates and evaluated their dual FAAH-MAGL inhibition properties. Phenyl [4-(piperidin-1-ylmethyl)phenyl]carbamate (2e) emerged as the most potent MAGL inhibitor (IC50 = 19 nM), benzyl (1H-benzo[d]imidazol-2-yl)carbamate (3h) was the most potent FAAH inhibitor (IC50 = 55 nM), and phenyl (6-fluorobenzo[d]thiazol-2-yl)carbamate (2i) egressed as a nonselective dual FAAH-MAGL inhibitor (FAAH: 82 nM, MAGL: 72 nM). The enzyme kinetics experiments revealed that the compounds inhibit FAAH/MAGL in a covalent-reversible manner, with a mixed binding mode of action. Moreover, the lead compounds were found suitable for blood-brain permeation in the parallel artificial membrane permeation assay. Furthermore, docking simulation experiments suggested that the potency of the lead compounds was governed by hydrogen bonds and hydrophobic interactions with the enzyme active sites. In silico drug-likeness and ADMETox prediction studies provided useful information on the compounds' oral absorption, metabolism, and toxicity profiles. In summary, this study afforded potent multifunctional carbamates with appreciable pharmacokinetic profiles meriting further investigation.


Assuntos
Carbamatos , Monoacilglicerol Lipases , Monoacilglicerol Lipases/metabolismo , Monoglicerídeos , Relação Estrutura-Atividade , Inibidores Enzimáticos , Amidoidrolases
16.
J Pathol Transl Med ; 56(4): 212-216, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35698740

RESUMO

BACKGROUND: Founder mutation is a heritable genetic alteration observed with high frequency in a geographically and culturally isolated population where one or more ancestors becomes the forebearer of the altered gene. The current study reports two founder mutations in the BRCA1 gene in the Nepalese people. METHODS: Germline BRCA testing in all surface epithelial ovarian cancers and the selected case of breast, prostate, and pancreatic cancers has been the standard practice from 2016 to 2021. One thousand one hundred thirtythree probands were screened for germline BRCA variants by next generation sequencing. The variants were classified as per the American Society of Medical Genetics and Genomics recommendations. Pathogenic (class V) and likely pathogenic (class IV) were considered clinically relevant and utilized for cascade screening. RESULTS: Nepalese population made up a subcohort of 5.12% (58/1,133) of probands tested for germline BRCA1/2 variants. Twenty-seven of these 58 tested harbored pathogenic genetic alterations in BRCA1/2 genes, with 23 being BRCA1 mutant. Sixteen of 23 BRCA1 mutant cases shared one common pathogenic mutation c.2214_2215insT (p.Lys739Ter) (NM_007294.4). Additionally, a second highly recurrent mutation in BRCA1 gene c.5068A>T (p.Lys1690Ter) (NM_007294.4) was noted in six patients from this population. CONCLUSIONS: The overwhelming abundance of the above two variants in a geographically confined population confers these two genetic alterations a status of founder mutations amongst the people of Nepal. A more extensive population-based study to reaffirm these findings will help establish a dual site-specific germline testing similar to the "Multisite-3-assay" in Ashkenazi Jews as the primary screening tool, especially in a resource-constrained environment.

17.
ACS Nano ; 16(6): 8983-8992, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35679485

RESUMO

Moiré superlattice (mSL)-induced sub-bands in twisted van der Waals homo- and heterostructures govern their optical and electrical properties, rendering additional degrees of freedom such as twist angle. Here, we demonstrate the moiré superlattice effects on the intralayer excitons and trions in a twisted bilayer of MoS2 of H-type stacking at marginal twist angles. We identify the emissions from localized and delocalized sub-bands of intralayer moiré excitons and show their electrical modulation by the corresponding trion formation. The electrical control of the oscillator strength of the moiré excitons also results in the strong tunability of resonant Raman scattering. We find that the gate-induced doping significantly modulates the electronic moiré potential; however, leaves the excitonic moiré confinement unaltered. This effect, coupled with variable moiré trap filling by tuning the optical excitation density, allows us to delineate the different phases of localized and delocalized moiré trions. We demonstrate that the moiré excitons exhibit strong valley coherence that changes in a striking nonmonotonic W-shape with gating due to motional narrowing. These observations from the simultaneous electrostatic control of quasiparticle-dependent moiré potential will lead to exciting effects of tunable many-body phenomena in moiré superlattices.

18.
ACS Nano ; 16(6): 9728-9735, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35604012

RESUMO

Strong Coulomb interactions in monolayer semiconductors allow them to host optically active large many-body states, such as the five-particle state, charged biexciton. Strong nonlinear light absorption by the charged biexciton under spectral resonance, coupled with its charged nature, makes it intriguing for nonlinear photodetection─an area that is hitherto unexplored. Using the high built-in vertical electric field in an asymmetrically designed few-layer graphene encapsulated 1L-WS2 heterostructure, here we report a large, highly nonlinear photocurrent arising from the strong absorption by two charged biexciton species under zero external bias (self-powered mode). Time-resolved measurement reveals that the generated charged biexcitons transfer to the few-layer graphene in a time scale of sub-5 ps, indicating an ultrafast intrinsic limit of the photoresponse. By using single- and two-color photoluminescence excitation spectroscopy, we show that the two biexcitonic peaks originate from bright-dark and bright-bright exciton-trion combinations. Such innate nonlinearity in the photocurrent due to its biexcitonic origin, coupled with the ultrafast response due to swift interlayer charge transfer, exemplifies the promise of manipulating many-body effects in monolayers toward viable optoelectronic applications.

19.
J Family Med Prim Care ; 11(3): 908-911, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35495820

RESUMO

Introduction: Current study was carried out as per the government of India and Himachal Pradesh guidelines to carry out a serosurvey to assess the extent of COVID-19 infection among health care professionals (HCPs) after 6 months of managing COVID-19 cases. Methods: A hospital-based survey was carried out among 1279 conveniently selected HCPs from September 2020 to January 2021. Results: The participants had a mean age of 38.3 (±10.4) years, and almost half (47.4%) were ≤35 years of age. A total of 29 (2.3%) were already tested positive for COVID-19 (RT-PCR: 22; Rapid Antigen Test: 7) before the survey, and the overall prevalence of IgG antibody was 12.7% among the participants (Male: 12.8%; Females: 12.5%). The odds were observed significantly high among administrative staff (aOR: 5.09; 95%CI: 1.27-20.33) and participants tested positive of COVID-19 previously (aOR: 28.41; 95%CI: 11.71-69.00). Conclusion: HCPs were tested about 6 months after the initiation of the COVID-19 pandemic in the state and demonstrated a high and expected level of seroprevalence.

20.
BMJ Open ; 12(4): e057530, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393321

RESUMO

INTRODUCTION: The launch of the Movement for Global Mental Health brought long-standing calls for improved mental health interventions in low-and middle-income countries (LMICs) to centre stage. Within the movement, the participation of communities and people with lived experience of mental health problems is argued as essential to successful interventions. However, there remains a lack of conceptual clarity around 'participation' in mental health interventions with the specific elements of participation rarely articulated. Our review responds to this gap by exploring how 'participation' is applied, what it means and what key mechanisms contribute to change in participatory interventions for mental health in LMICs. METHODS AND ANALYSIS: A realist review methodology will be used to identify the different contexts that trigger mechanisms of change, and the resulting outcomes related to the development and implementation of participatory mental health interventions, that is: what makes participation work in mental health interventions in LMICs and why? We augment our search with primary data collection in communities who are the targets of global mental health initiatives to inform the production of a programme theory on participation for mental health in LMICs. ETHICS AND DISSEMINATION: Ethical approval for focus group discussions (FGDs) was obtained in each country involved. FGDs will be conducted in line with WHO safety guidance during the COVID-19 crisis. The full review will be published in an academic journal, with further papers providing an in-depth analysis on community perspectives on participation in mental health. The project findings will also be shared on a website, in webinars and an online workshop.


Assuntos
Países em Desenvolvimento , Saúde Mental , COVID-19 , Humanos , Renda , Pobreza
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