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Aim: Obstetric patients presenting to the intensive care units (ICU) with or without underlying medical or surgical comorbidities can be a challenge to both the treating obstetrician and the intensivist. They occasionally present with near-miss events which if left untreated, can result in death. Objectives: To study the prevalence, indications of ICU admissions, near-miss events, and their effect on mortality in obstetric and puerperal patients. Material & methods: We conducted a retrospective analysis of the health records of all the obstetric and puerperal patients (pregnant and until 6 weeks postpartum) admitted to our tertiary care hospital from January 2019 to December 2020. Patient demographic characteristics, obstetric, surgical, and medical conditions, acute physiology, and chronic health evaluation (APACHE) II scores, organ failures, treatment, ICU and hospital length of stay, and mortality outcomes were studied. Results: A total of 22 obstetric patients were admitted to the ICU during the above study period. Mean age was 28.7 ± 6.24 years, mean gestation was 34.4 ± 6.61 weeks, mean APACHE II score was 12.68 ± 5.67, median ICU length of stay was 5 days, and median duration of hospital length of stay was 10 days. The antepartum risk factors such as severe preeclampsia (27%), antepartum bleeding (14%), and postpartum complications like postpartum haemorrhage (33%), sepsis with multiorgan failure (25%) are the commonest indications that resulted in ICU admission. Conclusion: Higher APACHE II scores at the time of ICU admission, prolonged ICU, and hospital length of stay may be associated with high maternal mortality.

•PPA was grown by solution growth method and it belongs to monoclinic system (P21/c).•PPA crystal has lower cut-off wavelength at 330 nm and band gap energy value is 3.8 eV.•The PPA crystal has thermal stability up to 88 °C and it belongs to be a soft material (n = 4.6) category.•PL spectrum has two emission peaks observed at 364 nm (violet) and 533 nm (green).•PPA has high SHG efficiency than KDP crystal.

Scheelite structured metal tungstate MWO4(M = Ni, Cu and Co) nanocubes were synthesized through the chemical reflux for supercapacitors application and ceyltrimethylammonium bromide (C-TAB) as surfactant. In X-ray diffraction (XRD) result are fit with relevant JCPDS cards, synthesized materials are closely matched with monoclinic and triclinic crystal phase corresponding to NiWO4, CoWO4and CuWO4with Scheelite type structure. To resist the growth of the particles and succeeding nanocubes morphology were achieving by using PEG-400 and C-TAB act as a surfactant. The prepared modified electrodes were examined electrochemical analysis after successive coating of working material in empty Ni foil. From the galvanostatic charge-discharge (GCD) comparative analysis, fast ions movements are interacts through the aqueous electrolyte medium with nanocubes NiWO4electrode are achieving specific capacitance of 1185 Fg−1at 0.5 Ag−1and cyclic stability 93.084 % (retentivity) formerly compare to CuWO4and CoWO4electrodes.

Metathesis ionic exchange reaction process was used to synthesize a novel nonlinear optical material: 4-N,N-dimethylamino-4′- N′-methylstilbazolium 2,4-dimethylbenzenesulfonate (DSDMS). The growth of DSDMS single crystals was carried out by adopting the solution growth technique. The crystal perfection and lattice parameters were elucidated from single XRD and powder XRD, respectively and its morphology was interpreted by WinXMorph program. FT-IR and Raman spectral analyses confirmed the existence of functional groups and their corresponding vibrational modes. UV-Vis spectral studies revealed the optical transmission region. Mechanical stability of the crystal was determined from Vickers microhardness number Hv, Meyer’s index n and elastic stiffness constant C11. Dielectric and thermal behavior of the grown crystal were elucidated by using impedance analyser and thermogravimetric analysis.

The investigations of ternary nanocomposite electrode based materials have been extensively studied for high-performance energy conversion/storage applications due to its large surface area, multivalent cations, and high stability with good electrical conductivity. Here, the ternary Co-Mn-Zn Oxide nanocomposite has been prepared by a facile and cost-effective hydrothermal approach. The synthesized materials were analyzed with various analytical tools to confirm structural, morphological, and elemental studies. The cyclic voltammetry (CV) analysis of Co-Mn-Zn Oxide nanocomposite manifests a high specific capacitance (Cs1) of 675.3 F/g at the scan rate of 10 mV/s. Electrochemical impedance spectroscopy (EIS) analysis exhibits the solution resistance (Rs) and charge-transfer resistance (Rct) of 0.44 Ω and 0.58 Ω. The galvanostatic charge-discharge (GCD) study shows a long charge/discharge time and better redox activities of the prepared ternary nanocomposite. The ternary Co-Mn-Zn Oxide nanocomposite reveals the coulombic efficiency of 100.6 % and capacitive retention of 94.5 % for 3000 charge-discharge cycles. Moreover, the Co-Mn-Zn Oxide//AC hybrid supercapacitor (HSC) device demonstrates a high energy density of 12.06 Wh/kg, a high power density of 3249.5 W/kg, Coulombic efficiency of 101.2 %, and good capacitive retention of 68.9 % for 2000 cycles.

Rare earth Sm+ ion doped potassium hydrogen phthalate (KHP) single crystal was grown by slow evaporation technique. Single crystal and powder X-ray diffraction analyses confirm the crystalline perfection of Sm+ ion doped KHP crystal. The functional groups of pure and Sm+ ion doped KHP crystals were identified by Fourier transform infrared spectroscopy (FTIR) spectral studies. Thermogravimetric and differential thermal analyses were carried out to study the thermal behavior of the grown crystals. UV–Vis studies explored the optical transmittance of the grown crystals in the entire visible region. The mechanical strength and etching studies were performed to assess the perfection of the pure and Sm+ ion doped KHP crystals. The refractive index and birefringence properties of the grown crystal were analyzed. The second harmonic generation efficiency of Sm+ ion doped KHP crystals was observed by Kurtz–Perry powder test. [ABSTRACT FROM AUTHOR]

Multiwalled Carbon Nanotubes (MWNT) have been activated by the application of electric field during the decoration of nanocrystalline Pt or Pd. This procedure results in enhanced ease in the decoration of Pt/Pd onto these MWNT. MWNT have been synthesised by Catalytic Chemical Vapour Deposition (CCVD) of acetylene using a novel fixed-bed catalytic reactor over hydrogen decrepitated Rare Earth (RE) based AB2 alloy hydride catalyst. Purified and chemically treated MWNT have been decorated with Pt/Pd using electric field resulting in dispersion of nanocrystalline Pt/Pd on the surface of MWNT. Structural, morphological and elemental analysis of Pt/Pd-MWNT have been carried out using X-ray Diffraction (XRD), Transmission Electron Microscopes (TEM) and Energy Dispersive X-ray (EDX). The presence of hydroxyl and carboxylic acid functional groups on the surface of MWNT and the increased hydrophilic nature of chemically treated MWNT on the dispersion of Pt/Pd has been discussed. The electric field assisted deposition allows the dispersion of nanocrystalline Pt/Pd with improved selectivity on Carbon Nanotubes (CNTs) and reduced metal deposition in the reaction solution.

Electrical resistivity studies on mischmetal-substituted, C15 type AB2alloy (Mm0.2Tb0.8Co2) hydrides with varied hydrogen interstitial concentrations have been carried out in the temperature range 80−300 K. Hydrogen concentration-dependent metal-semiconductor-like transition has been observed and explained based on the charge transfer between hydrogen and the 3d band and the reduction in 6S component of the electron density. Polycrystalline thin film of the alloy capped with palladium has been obtained by electron beam evaporation technique on clean glass substrates. Switching properties from reflecting to a transparent state by electrochemical polarization in an alkaline electrolyte of pH 13 at room temperature have been investigated. In addition, the cyclic durability of the films has been studied and compared with that of rare-earth-based switchable mirror films. Preferential interstitial site occupancy for the hydrogen atoms has been analyzed based on the curent voltage characteristics of alloy thin film.

An organic compound Bis DL-Valine picrate (BDLVP) was synthesized successfully and single crystal was grown by slow evaporation solution growth method. The presence of functional groups in the compound was identified by FTIR spectral analysis. Single crystal X-ray diffraction study revealed that the grown crystal belongs to P21/n space group of monoclinic crystal system. Powder X-ray diffraction pattern was recorded to know the crystalline perfection of the grown crystal. The reaction mechanism, thermal decomposition stages and thermal stability of the grown crystal were studied by using TG/DTA analysis. From the UV-visible spectral study, the electronic band gap energy (Eg) of the grown crystal was found to be 2.43 eV. The second harmonic generation (SHG) efficiency of grown crystal was found to be 1.3 times higher than KDP crystal by using Kurtz powder SHG technique. The microhardness property of the grown crystal was examined by Vicker's microhardness test.

2-Amino-4,6-dimethylpyrimidinium p-hydroxybenzoate (ADPHB), a novel organic material, was synthesized, and crystals were grown by slow evaporation solution growth method. The cell parameters and crystalline perfection of the grown crystal were studied by single crystal and powder X-ray diffraction analyses. The presence of various functional groups of the grown crystal was confirmed using Fourier Transform infrared spectral analysis. UV-Visible spectrum shows that ADPHB crystals have high transmittance in the range 305–900 nm. The refractive index and transient photoluminescence properties of the grown crystal were analyzed. The laser induced surface damage threshold, optical birefringence, and second harmonic generation efficiency of the grown crystal were studied.

In this letter, the effect of Ge diffusion at the gate area of AlxGa1-xN/GaN high electron mobility transistors (HEMTs) on a thin silicon-on-insulator (SOI) substrate has been investigated. The pinch-off voltage shifted toward enhancement mode type operation behavior due to the Ge diffusion through the surface of the thin GaN cap layer. An anomalous hump observed in high frequency C-V plot is due to the electron confinement at the Ge-GaN/AlGaN interface. The threshold voltage reduces by 0.8 to 1.0 V after Ge diffusion. The drive current and the transconductance further reduced as compared to the control sample due to the parallel channel formation at the top Ge-GaN/AlxGa1-xN interfaces.

Nine new substituted aryloxy-4-thiazolidones have been prepared from corresponding schiff bases and thioglycolic acid in benzene using Stark and Dien apparatus. The synthesized compounds were identified by spectral studies and screened for antimicrobial activity.