Two photon absorption in Mn<SUP>2+</SUP>-doped ZnSe quantum dots

The nonresonant third order nonlinear optical properties of three different sized Mn2+-doped ZnSe quantum dots (QDs) are investigated. The nonlinear absorption is measured at 532 nm using 35 picosecond laser pulses in an open-aperture Z-scan setup. Two photon absorption (2PA) cross-section in ZnSe QDs is found to be three orders of magnitude higher than its bulk value. These nanostructures show size dependent nonlinear absorption coefficients. It is found that the 2PA further enhances with decrease in size of the QD and is twice that of its undoped counterpart due to change in the local electric field

Two-photon absorption in ZnSe and ZnSe/ZnS core/shell quantum structures

The third order nonlinear optical properties of two different sized ZnSe and ZnSe/ZnS quantum dots (QDs) are investigated. The nonlinear absorption is measured at 806 nm using Ti:sapphire 100 fs laser pulses in an open aperture Z-scan setup. Two-photon absorption (2PA) is found to be dominant in core and core shell QDs. 2PA cross section is enhanced by three orders of magnitude compared bulk ZnSe. 2PA cross section is observed to increase with reduction in QD diameter, due to strong confinement effect. ZnSe/ZnS QDs exhibit higher 2PA cross section compared with corresponding ZnSe QDs, indicating better passivation of the QD surface

Antioxidant and antimicrobial potential of Canavalia gladiata (Jacq.) DC. leaves and seeds: GC-MS based metabolic profiling

Canavalia gladiata (Sword Bean; family Fabaceae) is a fast-growing climber crop that has been widely cultivated in tropical and subtropical areas for its edible seeds and legumes. It has also been used as grain legume and medicinal plant in China for thousands of years. The metabolites from leaves and seeds of C. gladiata were extracted in petroleum ether and chloroform. Further, extracts were subjected to GC-MS analysis for metabolite profiling. Total of 31 phytoconstituents were identified; 14 compounds were reported to have biological activities. The Tridecane reported from leaves and seeds petroleum ether extract showed 10.67 and 2.72% of relative quantity of compound respectively and has antioxidant and antimicrobial activity. Octasiloxane,1,1,3,3,5,5,7,7,9,9,11,11,11,15,15-hexadecamethyl (3.42%) found in petroleum ether leaves extracts showed antimicrobial activity. Moreover, 1- Hexadecane constituted 10.23% in seeds and 3.71% relative quantity in leaves extracted with chloroform showed antibacterial activity. The seeds and leaves extracted with chloroform reported 1-Tetradecene in 6.59 and 6.03% relative quantity respectively has antifungal potential. While Phenol 2, 4-bis [1, 1-dimethylethyl] reported in leaves (6.12%) and seeds (6.47%) chloroform extract act as antioxidant and antimicrobial agents. The 1-Nonadecene in seeds (3.47%) and leaves (2.14%) chloroform extracts showed antifungal activity while 1-Docosene in seeds (2.98%) and leaves (1.71%) of chloroform extract showed antimicrobial potential. Nonadecane constituted 3.06% in seeds and 2.78% in leaves chloroform extracts and has antioxidant potential. The present study revealed that the leaves and seeds of C. gladiata are a good source of antioxidants and other biologically active ingredients. However, petroleum ether and chloroform extracted different metabolites from seeds and leaves. Therefore, these findings highlighted the importance of solvent in phytochemical extractions and further bioactivity of C. gladiata metabolites creates an attention of researchers for their use in the field of paramedical industries and herbal medicine

Safety and Efficacy of Paracetamol + Lignocaine Injection in Patients with High-grade Fever:A Prospective Analysis

Paracetamol is frequently used as an analgesic and antipyretic across the world. However, there is no data on Indian patients regarding the safety and efficacy of paracetamol + lignocaine injection in patients with high-grade fever. Hence, a prospective analysis was conducted to assess the safety and efficacy of paracetamol and lignocaine injection in patients with high-grade fever and mild-to-moderate body pain. The study is a real-world prospective study. The results showed that following intervention with paracetamol and lignocaine injection, 98% patients showed resolution of fever and 58% patients showed improvement in pain symptoms. The authors suggest that clinicians should consider paracetamol and lignocaine injection in patients with high-grade fever and associated pain and discomfort

Effect of Community-Initiated Kangaroo Mother Care on Fecal Biomarkers of Gut Function in Low Birth Weight Infants in North India : A Randomized Clinical Trial

This individually randomized trial was conducted to estimate the effect of promoting community-initiated Kangaroo Mother Care (ciKMC) in low birth weight (LBW) infants on gut inflammation and permeability. Participants included 200 stable LBW infants (weighing 1,500–2,250 g) in North India enrolled between May and October 2017. The ciKMC intervention included promotion and support of continuous skin-to-skin contact and exclusive breastfeeding through home visits. The mothers in the intervention arm were supported to practice ciKMC until 28 days after birth, i.e., the neonatal period, or till the baby wriggled out of KMC position, if earlier. Infant stool specimens were collected during the first week of birth, and within 1 week after end of the neonatal period. Concentrations of fecal neopterin (nmol/L), myeloperoxidase (ng/mL), and alpha-1-antitrypsin (μg/mL) were determined using ELISA, and composite enteric enteropathy (EE) score at the end of the neonatal period was calculated by principal component analysis. We did not find any substantial difference in means between the ciKMC and control arm infants in the log-transformed values of neopterin (0.03; 95% CI −0.15 to 0.21), myeloperoxidase (0.28; 95% CI −0.05 to 0.61) and alpha-1-antitrypsin (0.02; 95% CI −0.30 to 0.34). The mean (SD) composite EE score was 13.6 (7.5) in the ciKMC and 12.4 (8.3) in the control arm infants, and the adjusted difference in means was, 0.4 (95% CI −1.8 to 2.7). Our findings suggest that the promotion of ciKMC did not affect gut inflammation and permeability in our target population of LBW infants in North India.acceptedVersionPeer reviewe

Science with the Daksha High Energy Transients Mission

We present the science case for the proposed Daksha high energy transients mission. Daksha will comprise of two satellites covering the entire sky from 1~keV to $>1$~MeV. The primary objectives of the mission are to discover and characterize electromagnetic counterparts to gravitational wave source; and to study Gamma Ray Bursts (GRBs). Daksha is a versatile all-sky monitor that can address a wide variety of science cases. With its broadband spectral response, high sensitivity, and continuous all-sky coverage, it will discover fainter and rarer sources than any other existing or proposed mission. Daksha can make key strides in GRB research with polarization studies, prompt soft spectroscopy, and fine time-resolved spectral studies. Daksha will provide continuous monitoring of X-ray pulsars. It will detect magnetar outbursts and high energy counterparts to Fast Radio Bursts. Using Earth occultation to measure source fluxes, the two satellites together will obtain daily flux measurements of bright hard X-ray sources including active galactic nuclei, X-ray binaries, and slow transients like Novae. Correlation studies between the two satellites can be used to probe primordial black holes through lensing. Daksha will have a set of detectors continuously pointing towards the Sun, providing excellent hard X-ray monitoring data. Closer to home, the high sensitivity and time resolution of Daksha can be leveraged for the characterization of Terrestrial Gamma-ray Flashes.Comment: 19 pages, 7 figures. Submitted to ApJ. More details about the mission at https://www.dakshasat.in

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Synthesis and characterization of photosensitive TiO2 nanorods by controlled precipitation route

Nanocrystalline TiO2 thin films have been successfully synthesized by controlled precipitation route. These films are further annealed at 623 K for 2 h. The change in structural, morphological, optical, and wettability properties are studied by means of X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), scanning electron microscopy (SEM), optical absorption, and contact angle measurement. From the XRD pattern it is clear that the as-grown TiO2 films are amorphous in nature which becomes polycrystalline after annealing. The FTIR study reveals the formation of TiO2 compound. Scanning electron micrographs shows that the as-grown TiO2 film consists of agglomerated nanograins well covered to the substrate surface which gets converted into vertical nanorods after annealing. As-deposited and annealed TiO2 films showed hydrophilic behavior as water contact angles were 24° and 32°, respectively. The optical absorption study reveals the small red shift due to annealing and attributed to grain size. The annealed TiO2 film showed conversion efficiency of 0.037% in photoelectrochemical cell with 1 M NaOH electrolyte. © 2010 Springer Science+Business Media, LLC