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1.
ACS Appl Mater Interfaces ; 16(24): 31738-31746, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38843175

RESUMO

Assembling two-dimensional van der Waals (vdW)-layered materials into heterostructures is an exciting development that sparked the discovery of rich correlated electronic phenomena. vdW heterostructures also offer possibilities for designer device applications in areas such as optoelectronics, valley- and spintronics, and quantum technology. However, realizing the full potential of these heterostructures requires interfaces with exceptionally low disorder which is challenging to engineer. Here, we show that thermal scanning probes can be used to create pristine interfaces in vdW heterostructures. Our approach is compatible at both the material- and device levels, and monolayer WS2 transistors show up to an order of magnitude improvement in electrical performance from this technique. We also demonstrate vdW heterostructures with low interface disorder enabling the electrical formation and control of quantum dots that can be tuned from macroscopic current flow to the single-electron tunneling regime.

5.
J Family Med Prim Care ; 12(9): 1808-1813, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38024923

RESUMO

Nearly 45% of under 5 mortality is directly or indirectly linked to malnutrition. Infection adds to the increased mortality and morbidity in these groups. Vaccination is very important in these undernourished children protecting against life-threatening infections. The goal of vaccination is to produce long-term protection by generating memory cells and the generation of antibodies. Since malnutrition is a state of immunodeficiency, the immune response to vaccines in these children is a matter of concern. We did an exhaustive search to gather more recent studies and corroborated previous findings. Oral Polio Vaccine (OPV), Pneumococcal Polysaccharide Vaccine, Haemophilus influenza vaccine, rabies, and cholera vaccine showed normal response to immunization. Measles and rotavirus vaccines were found to elicit lower seroprotection and lower efficacy in undernourished children. Data regarding response to vaccination against BCG, DPwT, Hepatitis B, pneumococcal conjugate vaccine, and meningococcal vaccine was inconclusive. Although most of the studies show a normal immune response to different vaccines, excluding other confounding factors and effect modifiers had not been easy to interpret. However, with the advances in the understanding of vaccine physiology with newer immunological techniques, good-quality studies might explore the gray areas that remain untouched.

6.
Nat Commun ; 14(1): 4679, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542024

RESUMO

Excitonic states trapped in harmonic moiré wells of twisted heterobilayers is an intriguing testbed for exploring many-body physics. However, the moiré potential is primarily governed by the twist angle, and its dynamic tuning remains a challenge. Here we demonstrate anharmonic tuning of moiré potential in a WS2/WSe2 heterobilayer through gate voltage and optical power. A gate voltage can result in a local in-plane perturbing field with odd parity around the high-symmetry points. This allows us to simultaneously observe the first (linear) and second (parabolic) order Stark shift for the ground state and first excited state, respectively, of the moiré trapped exciton - an effect opposite to conventional quantum-confined Stark shift. Depending on the degree of confinement, these excitons exhibit up to twenty-fold gate-tunability in the lifetime (100 to 5 ns). Also, exciton localization dependent dipolar repulsion leads to an optical power-induced blueshift of ~ 1 meV/µW - a five-fold enhancement over previous reports.

7.
J Family Med Prim Care ; 12(5): 1006-1008, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37448929

RESUMO

Corticosteroids are potent anti-inflammatory agents used as a mainstay of therapy in most of the rheumatologic disorders. Common side effects of pulse steroid therapy include hypertension, hyperglycemia, seizure, hypokalemia, and infection. We report a case of an 11-year-old girl with polyarticular Juvenile idiopathic arthritis who developed bradycardia following pulse methylprednisolone therapy. On day 2 of methylprednisolone infusion, she developed bradycardia with a heart rate between 50 and 60/min. ECG was suggestive of sinus bradycardia. There was no evidence of dyselectrolytemia (Na-141 mmol/l, K-3.54 mmol/l, Ca-8.72 mg/l) or sepsis. The patient did not receive methylprednisolone on day 3 and vitals continued to be monitored. Her heart rate improved after 12 hours. In the mid of infusion on day 4, again the patient had bradycardia with a heart rate of 50-60/minute. Since she was hemodynamically stable, we continued the infusion, and bradycardia resolved in the next 8 hours. On follow-up after 2 weeks, she had some improvement in joint symptoms and normal heart rate. As per Naranjo adverse drug reaction probability scale, the adverse reaction in our case was probable with a score of 8. Although bradycardia associated with pulse steroid therapy is benign and is usually reversible following cessation of therapy, a baseline heart rate, ECG, and electrolyte level are suggested before infusion as a cautionary measure to minimize serious adverse events.

8.
Indian Pediatr ; 60(8): 641-643, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209051

RESUMO

OBJECTIVE: To study the prevalence of common dyslipidemia among overweight and obese children between 2-18 years in a tribal region. METHODS: This cross-sectional study was carried out in 151 overweight and obese children aged 2-18 years, who visited the pediatric outpatient department of a tertiary care hospital in Jharkhand between 1 August and 30 November, 2022. Dyslipidemia was defined as anyone of the following: a total cholesterol level of 240 mg/dL, a triglyceride level of 150 mg/dL, a low-density lipoprotein cholesterol level (LDL-C) of 140 mg/dL, a high-density lipoprotein cholesterol level (HDL-C) of 40 mg/dL, or the use of a lipid-lowering drug [8]. Overweight and obesity were defined as per World Health Organization criteria. RESULTS: The prevalence of dyslipidemia was 63.6%. The most common type of dyslipidemia was low HDL-C + high TG levels found in 32.5% (n=49) children. The most prevalent pattern of dyslipidemia in overweight children was low HDL-C (19, 32.3%); and in obese children low HDL-C and high TG levels (39, 42.3%). CONCLUSION: The prevalence rate of dyslipidemia was high among overweight and obese children in this region. There was a positive association between dyslipidemia and body mass index.


Assuntos
Dislipidemias , Obesidade Infantil , Criança , Humanos , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Estudos Transversais , Triglicerídeos , Dislipidemias/epidemiologia , Prevalência , Hospitais , Colesterol , HDL-Colesterol
9.
ACS Nano ; 17(11): 9870-9905, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37257134

RESUMO

Despite over a decade of intense research efforts, the full potential of two-dimensional transition-metal dichalcogenides continues to be limited by major challenges. The lack of compatible and scalable dielectric materials and integration techniques restrict device performances and their commercial applications. Conventional dielectric integration techniques for bulk semiconductors are difficult to adapt for atomically thin two-dimensional materials. This review provides a brief introduction into various common and emerging dielectric synthesis and integration techniques and discusses their applicability for 2D transition metal dichalcogenides. Dielectric integration for various applications is reviewed in subsequent sections including nanoelectronics, optoelectronics, flexible electronics, valleytronics, biosensing, quantum information processing, and quantum sensing. For each application, we introduce basic device working principles, discuss the specific dielectric requirements, review current progress, present key challenges, and offer insights into future prospects and opportunities.

10.
ACS Nano ; 17(8): 7929-7939, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37021759

RESUMO

Two-dimensional (2D) semiconductors are promising channel materials for continued downscaling of complementary metal-oxide-semiconductor (CMOS) logic circuits. However, their full potential continues to be limited by a lack of scalable high-k dielectrics that can achieve atomically smooth interfaces, small equivalent oxide thicknesses (EOTs), excellent gate control, and low leakage currents. Here, large-area liquid-metal-printed ultrathin Ga2O3 dielectrics for 2D electronics and optoelectronics are reported. The atomically smooth Ga2O3/WS2 interfaces enabled by the conformal nature of liquid metal printing are directly visualized. Atomic layer deposition compatibility with high-k Ga2O3/HfO2 top-gate dielectric stacks on a chemical-vapor-deposition-grown monolayer WS2 is demonstrated, achieving EOTs of ∼1 nm and subthreshold swings down to 84.9 mV/dec. Gate leakage currents are well within requirements for ultrascaled low-power logic circuits. These results show that liquid-metal-printed oxides can bridge a crucial gap in dielectric integration of 2D materials for next-generation nanoelectronics.

12.
Front Public Health ; 11: 1303095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38303961

RESUMO

Malaria poses a major public health challenge in the Asia Pacific. Malaria Elimination Demonstration Project was conducted as a public-private partnership initiative in Mandla between State government, ICMR, and FDEC India. The project employed controls for efficient operational and management decisions. IEC campaigns found crucial in schools and communities. Capacity building of local workers emphasized for better diagnosis and treatment. SOCH mobile app launched for complete digitalization. Better supervision for Indoor Residual Sprays and optimized Long Lasting Insecticidal Nets distribution. Significant malaria cases reduction in Mandla. Insights from MEDP crucial for malaria elimination strategies in other endemic regions of the Asia Pacific.


Assuntos
Inseticidas , Malária , Humanos , Ásia/epidemiologia , Índia , Malária/prevenção & controle , Malária/epidemiologia , Saúde Pública
13.
15.
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.

16.
Lancet Reg Health West Pac ; 22: 100429, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35466325

RESUMO

In Asia Pacific, several nations that were part of the World Health Organization's initiative to eliminate malaria by 2020 or the E2020 Initiative reported being off-track. The COVID-19 pandemic further strained health systems and has the potential to stall the efforts and reverse earlier progress made towards the fight against malaria. These nations have since recommitted to eliminating malaria by 2025, in a renewed E2025 Initiative. This viewpoint presents efforts of the national malaria programs in Bhutan and Timor-Leste as they prepare for this new commitment. It includes insights on the approaches adapted by both countries that have helped them keep the spotlight on malaria whilst preventing large COVID-19 outbreaks. This viewpoint proposes key strategies that near-elimination countries can consider to sustain malaria interventions and realize their elimination goal. Of note, it calls for national strategic plans to consider a whole-of-government approach to ensure progress - which includes sustaining political commitment, systematically collaborating across borders, empowering communities and strengthening health systems particularly through surveillance and data management - that will benefit all existing and future infectious threats and pave the way for integrated response mechanisms across diseases.

17.
Biointerphases ; 18(6)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38078794

RESUMO

Cold atmospheric pressure plasma jet (CAPJ) has piqued the interest of researchers for various antimicrobial applications such as disinfection, wound decontamination, etc. In the current context, a deeper understanding of the correlation between CAPJ's intrinsic parameters, discharge characteristics, species composition, and antimicrobial activity is required for any successful application. This research evaluated the effect of intrinsic operational parameters such as voltage, frequency, gas flow rate, and operating gas on the reactive species composition of an in-house-developed CAPJ discharge along with the antimicrobial activity. It was observed that the identified excited atoms (Ar I, He I, N2, and O I), ions (Ar+, N2+, N+, H2O+, H3O+, etc.), radical reactive oxygen and nitrogen species (RONS) (OH•), and nonradical RONS (O I, O+, OH+, NO+, O2+, O2-, NO2-, N2O2-, NO3-, N2O3-, etc.) might play a synergistic role in bacterial inactivation via oxidative and electrostatic stress. The variation in voltage, frequency, gas flow rate, and operating gas influenced the discharge chemistry, leading to variation in bacterial inactivation. The reactive species in the discharge responsible for such variation was evaluated extensively. This investigation into various operational parameters would aid in determining the most effective settings for a developed CAPJ to achieve high productivity.

18.
Sci Rep ; 11(1): 15017, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294863

RESUMO

We report strong second-harmonic generation (SHG) from 2H polytype of multilayer Tin diselenide (SnSe2) for fundamental excitation close to the indirect band-edge in the absence of excitonic resonances. Comparison of SHG and Raman spectra from exfoliated SnSe2 flakes of different polytypes shows strong (negligible) SHG and Raman Eg mode at 109 cm-1 (119 cm-1), consistent with 2H (1T) polytypes. The difference between the A1g-Eg Raman peak positions is found to exhibit significant thickness dependent for the 1T form, which is found to be absent for the 2H form. The observed thickness dependence of SHG with rapid oscillations in signal strength for small changes in flake thickness are in good agreement with a nonlinear wave propagation model considering nonlinear polarization with alternating sign from each monolayer. The nonlinear optical susceptibility extracted from SHG signal comparison with standard quartz samples for 1040 nm excitation is found to be more than 4-times higher than that at 1550 nm. This enhanced nonlinear response at 1040 nm is attributed to the enhanced nonlinear optical response for fundamental excitation close to the indirect band-edge. We also study SHG from heterostructures of monolayer MoS2/multilayer SnSe2 which allows us to unambiguously compare the nonlinear optical response of SnSe2 with MoS2. We find the SHG signal and any interference effect in the overlap region to be dominated by the SnSe2 layer for the excitation wavelengths considered. The comparison of SHG from SnSe2 and MoS2 underscores that the choice of the 2D material for a particular nonlinear optical application is contextual on the wavelength range of interest and its optical properties at those wavelengths. The present works further highlights the usefulness of near band-edge enhancement of nonlinear processes in emerging 2D materials towards realizing useful nanophotonic devices.

20.
Health Syst Reform ; 6(2): e1840825, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33252995

RESUMO

On the global health agenda, Universal Health Coverage has been displaced by the COVID-19 pandemic while disparities in COVID-19 outcomes have exposed stark gaps in quality, access, equity, and financial risk protection. These disparities highlight the importance of the core goals of Universal Health Coverage and the need for innovative approaches to working toward them. The newly codified concept of "Networks of Care" offers a promising option for implementation. The articles in this special issue present the Networks of Care lexicon and framework and demonstrate the development of leadership, responsibility, intra- and inter-facility cooperation, and dynamic cycles of quality improvement. These elements are associated with better access to services and better health outcomes, the ultimate goals of Universal Health Coverage. Increases in poverty, food insecurity, and deleterious impact on the status of women secondary to the COVID-19 pandemic add urgency to Universal Health Coverage, while the economic impact of pandemic mitigation may reduce availability of resources for years to come. The need for Universal Health Coverage and efficiency and flexibility in health spending, including the ability to contract directly, has become even more important. Countries where Universal Health Coverage efforts have yet to carry through to provision of good quality, accessible and equitable service delivery could potentially benefit from concurrent Networks of Care implementation. Documentation of Networks of Care in the context of Universal Health Coverage should be prioritized to understand how Networks of Care can be used to help realize the goals of Universal Health Coverage around the world.


Assuntos
COVID-19 , Assistência Integral à Saúde/organização & administração , Saúde Global , Reforma dos Serviços de Saúde , Equidade em Saúde , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde , COVID-19/economia , COVID-19/epidemiologia , Equidade de Gênero , Gastos em Saúde , Financiamento da Assistência à Saúde , Humanos , Pandemias , SARS-CoV-2 , Cobertura Universal do Seguro de Saúde
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