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Inorganic perovskite lasers are of particular interest, with much recent work focusing on Fabry-Pérot cavity-forming nanowires. We demonstrate the direct observation of lasing from transverse electromagnetic (TEM) modes with a long coherence time ∼ 9.5 ps in coupled CsPbBr3 quantum dots, which dispense with an external cavity resonator and show how the wavelength of the modes can be controlled via two independent tuning-mechanisms. Controlling the pump power allowed us to fine-tune the TEM mode structure to the emission wavelength, thus providing a degree of control over the properties of the lasing signal. The temperature-tuning provided an additional degree of control over the wavelength of the lasing peak, importantly, maintained a constant full width at half maximum (FWHM) over the entire tuning range without mode-hopping. [ABSTRACT FROM AUTHOR]

Diminishing surface defect states in perovskite nanocrystals is a highly challenging subject for enhancing optoelectronic device performance. We synthesized organic/inorganic lead-halide perovskite MAPbBr3 (MA = methylammonium) clusters comprising nanocrystals with diameters ranging between 20–30 nm and characterized an enhanced photoluminescence (PL) quantum yield (as much as ~ 7 times) by encapsulating the MAPbBr3 with graphene (Gr). The optical properties of MAPbBr3 and Gr/MAPbBr3 were investigated by temperature-dependent micro-PL and time-resolved PL measurements. Density functional theory calculations show that the surface defect states in MAPbBr3 are removed and the optical band gap is reduced by a 0.15 eV by encapsulation with graphene due to partial restoration of lattice distortions. [ABSTRACT FROM AUTHOR]

Polycrystalline n-type CdSe thin films were deposited from aqueous bath at room temperature by periodic voltammetry for use in photo-electrochemical (PEC) solar cells. The influence of periodic scans on the functional properties of the chalcogenide films was thoroughly investigated through electron microscopy (SEM), X-ray diffraction (XRD), UV-visible spectrometry, and electrochemical techniques. The film thickness increases with the number of periodic scans, and the spectral measurements identify the optical band gap in the range 1.55-1.72 eV. The CdSe films show typical X-ray diffraction patterns of hexagonal crystal structure with particle size 20-30 nm, uniformly distributed throughout the matrix. PEC characteristics including photo-current density, conversion efficiency ( η), fill factor ( FF), and durability of the films were evaluated by the help of respective electrochemical techniques. The voltammetric cycle number was optimized which enable to identify the best CdSe film exhibiting photo-conversion efficiency of ~1% with minimum photocurrent decay. [ABSTRACT FROM AUTHOR]

The effect of incorporating whey protein concentrate (WPC) on the quality characteristics of Mozzarella cheese analogue (MCA) based on rennet casein (RC) was studied. The proportion of RC:WPC tried out were 95:5, 90:10, and 85:15 w/w. The formulation of MCA comprised of 23.5% of blend of RC and WPC, 15% specialty vegetable fat, 2.75% trisodium citrate + disodium hydrogen orthophosphate (2.5:1, w/w), 0.07% calcium chloride, 0.6% citric acid, 1.1% NaCl, 1.5% cheese bud flavoring, and rest water. Varying the proportion of RC and WPC had a significant influence on the composition, textural properties, baking qualities and sensory quality of MCA judged as a topping on pizza pie. MCA made using protein blends (RC:WPC-90:10 or 85:15) behaved satisfactorily during pizza baking trials. However, looking at the superiority of MCA made using RC:WPC (90:10) with regard to shred quality and marginal superiority in terms of the total sensory score of cheese, judged as pizza topping, the former blend (i.e. RC:WPC, 90:10) was selected. The MCA obtained employing such protein blend had composition similar to that of Pizza cheese prepared from cheese milk and had requisite baking characteristics needed as a pizza topping. It is recommended to use a blend of RC and WPC (90:10) as the protein source in the formulation of MCA to obtain nutritionally superior cheese product having desired functional properties for its end use in baking applications. [ABSTRACT FROM AUTHOR]

The conventional dye sensitized solar cell (DSSC) comprise of mostly the titania matrix sensitized with absorber dye molecules acting as light energy scavengers. The present investigation deals with formulating CdS-TiO conjugate matrix for the DSSC system using N3 dye sensitizer. TiO nanoparticles (NPs) were pasted on FTO glass substrate and thin film of CdS was coated on titania matrix by chemical bath deposition technique using precursors cadmium acetate and thiourea. The differential absorbance spectra of the CdS-TiO conjugate system shows sharp absorption edges around 345-500 nm, corresponding to band gap energies in the region 3.59 and 2.47 eV respectively, indicative of formation of two distinguishable energy region for the existence of the nano crystallites of both TiO and CdS. The shift in Raman bands was also observed with the incorporation of CdS in TiO matrix. XRD data confirms the formation of crystalline CdS nanoparticles. The FE-SEM images revealed that the TiO particles are spherical and monodispersed having diameter in the range 20-30 nm and embedded with CdSNPs of average particle size 10-15 nm. The performance characteristics of the synthesized films towards photovoltaic behavior were studied with the record of short circuit currents through J- V measurement using N3 absorber dye and the I/I electrolyte under 30 mW cm light intensity. An effective increase of efficiency is observed with the CdS modified TiO matrix compared to the bare TiO in the DSSC system and a maximum photo-conversion efficiency of 7.5 % was obtained with the optimized dye loading. Impedance spectroscopic measurements give important information about the interfacial electron injection and recombination dynamics of the device. The incident photon-to-current conversion efficiency measurements show that both the absorbers CdS and N3 dye, contribute to the cell performance. [ABSTRACT FROM AUTHOR]

Objective: To implement a neonatal hearing screening program using automated auditory brainstem response audiometry in a tertiary care set-up and assess the prevalence of neonatal hearing loss. Design: Descriptive study. Setting: Tertiary care hospital in Southern India. Participants: 9448 babies born in the hospital over a period of 11 months. Intervention: The neonates were subjected to a two stage sequential screening using the BERAphone. Neonates suspected of hearing loss underwent confirmatory testing using auditory steady state response audiometry. In addition, serological testing for TORCH infections, and connexin 26 gene was done. Main outcome measures: Feasibility of the screening program, prevalence of neonatal hearing loss and risk factors found in association with neonatal hearing loss. Results: 164 babies were identified as suspected for hearing loss, but of which, only 58 visited the audiovestibular clinic. Among 45 babies who had confirmatory testing, 39 were confirmed to have hearing loss and were rehabilitated appropriately. 30 babies had one or more risk factors; 6 had evidence of TORCH infection and 1 had connexin 26 gene mutation. Conclusion: Neonatal hearing screening using BERA phone is a feasible service. The estimated prevalence of confirmed hearing loss was comparable to that in literature. Overcoming the large numbers of loss to follow-up proves to be a challenge in the implementation of such a program. [ABSTRACT FROM AUTHOR]

Objective: To study the perinatal outcomes of infants born to mothers with gestational diabetes treated with insulin or oral hypoglycemic agents in a developing country. Design: Prospective observational cohort study. Setting: Tertiary-care perinatal center in southern India. Participants: Babies born to mothers with gestational diabetes. Methods: Maternal details were obtained and physical examination was performed on the neonates. Babies were given hourly feeds soon after birth and blood glucoses checked at 1, 3, 5,9 and 12 hours of life; hematocrit and calcium levels were also measured. Perinatal outcomes were compared between mothers who required insulin or an oral hypoglycemic agent fortreatment of diabetes. Results: Of the 10,394 mothers who delivered during the study period, 574 (5,5%) were diagnosed to have gestational diabetes. 137 were treated with insulin and 141 witrforal hypoglycemic agents. 44 (15.8%) babies were born preterm, 97 (35%) were large for gestational age, 13 (4.7%) were small for gestational age and 9 (3.2%) were macrosomic. Hypoglycemia was seen in 26 (9.3%) babies, congenital anomalies in 15 (5.4%) and birth injuries in 7 (2.5%). There was no difference between the two groups in any of the outcomes except for hyperbilirubinemia, which was more in the insulin group (13.7% vs6.5%, P=0.04). Conclusions: There was no difference in the perinatal outcome whether the mother received insulin or an oral hypoglycemic agent for treatment of gestational diabetes other than the increased incidence of hyperbilirubinemia in the insulin group [ABSTRACT FROM AUTHOR]

Objective: To determine the feasibility and safety of whole body cooling in newborn infants with perinatal asphyxial encephalopathy in a low resource setting. Design: Feasibility trial. Setting: Tertiary care perinatal centre. Subjects: Infants born at ≥ 35 weeks gestation with perinatal asphyxia were included in the study. Interventions: Infants were cooled to a rectal temperature of 33±0.5°C for 72 hours using cloth-covered ice-gel packs. Vital parameters were monitored continuously. Outcome measures: The primary outcome was the achievement of target temperature within 1 hour of initiation of treatment and maintaining the target temperature for 72 hours. Adverse events and possible complications of hypothermia were the secondary outcomes measured. Results: Twenty infants were included in the study. The mean time taken to achieve target rectal temperature was 52±25 minutes. The mean rectal temperature during cooling was 32.9±0.11°C. The target temperature could be maintained for 72 hours without difficulty in all babies. Adverse events observed during cooling were thrombocytopenia (25%), sinus bradycardia (25%), deranged bleeding parameters (20%), aposteatonecrosis (15%), hyperglycemia (15%), hypoglycemia (10%), hypoxemia (5%), life-threatening coagulopathy (5%) and death (5%). Shivering was noted in many of the babies, especially in the initial phase of cooling. Conclusion: Whole body cooling in term infants with perinatal asphyxia is achievable, safe and inexpensive in a low-resource setting. [ABSTRACT FROM AUTHOR]

Short rib polydactyly syndrome (SRPS) consists of a group of lethal skeletal dysplasias presenting with short limbs and ribs, hypoplastic thorax and polydactyly with or without visceral abnormalities. The authors report a case of SRPS in a fresh stillborn baby who had these features along with dysplastic kidneys. Clinical and radiological findings in this baby were consistent with SRPS - Type I (Saldino-Noonan Type). The diagnosis of SRPS, as in this case, can be made by antenatal ultrasonography. [ABSTRACT FROM AUTHOR]

process for manufacture of Mozzarella cheese analogue (MCA) using rennet casein and plastic cream as protein and fat sources respectively was standardized. The formulation comprised of 25% plastic cream (72% fat), 27% rennet casein along with 3% tri-sodium citrate as emulsifying salt, 2% maltodextrin as binder, 0.55% lactic acid as pH regulator, 1% common salt for seasoning, 1% Mozzarella cheese bud as flavouring and 40.4% water. The process involved (a) dissolving the dry mixture of casein, maltodextrin, flavouring and common salt in hot emulsifying salt solution, (b) incorporation of half the quantity of acid solution in casein-maltodextrin dough, followed by addition and emulsification of plastic cream, and (c) addition of remaining half of the acid solution and heating the mass to 80 °C until a plastic cheese mass was obtained. The analogue was shaped in ball form, cooled and packaged in polyethylene bag. The MCA conformed to the PFA requirements for pizza cheese and had all the requisite baking characteristics expected of pizza cheese topping. [ABSTRACT FROM AUTHOR]

low fat mango ice cream (2.4% milk fat) was prepared in a mechanized 'ice and salt' type freezer using powdered sago at 2.5% as a natural bulking agent along with sodium alginate at 0.025% as adjunct. The low fat mango ice cream was compared with control mango ice cream having 10% milk fat and 0.15% sodium alginate as stabilizer. Both control as well as experimental ice creams contained 20% mango pulp solids. To impart richness to low fat mango ice cream, flavour enhancers like Cream Plus and Butter Buds were used at levels of 0.2% and 0.05%, respectively. The dietetic low fat ice creams compared well in sensory colour and appearance, flavour, body and texture, and melting quality to that of control ice cream. Incorporation of 2.5% powdered sago and 0.2% Cream Plus as flavour adjunct is recommended in the manufacture of 'low-fat' mango ice cream. The energy values for control and dietetic mango ice cream was 202.8 and 142.9 kcal/100 g, respectively, which represents about 30% reduction in calorie. The cost of ice cream per liter was Rs 39.9, Rs 37.6 and Rs 49.7 for experimental ice creams containing Cream Plus and Butter Bud, and control, respectively. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide (TMD) nanosheets (NSs) with defect-rich and vertically aligned edges are highly advantageous for various catalytic applications. However, colloidal synthesis of defect-rich NSs with thickness variation has been a challenging task. Here, we report a colloidal synthesis of 2H-MoSe 2 NSs having a large number of defects and vertically aligned edges, where the thickness is varied by changing the amount of coordinating solvent. The Se-vacancies in these NSs have introduced defect sites which are corroborated by the presence of additional vibration modes in Raman spectra. These NSs exhibit electrocatalytic hydrogen evolution reaction performances with a low overpotential (210–225 mV) at 10 mA cm - 2 current density and a small Tafel slope (54–68 mV per decade). Moreover, these MoSe 2 NSs are also employed as counter electrodes (CEs) for the fabrication of dye sensitized solar cells via a cost-effective and simplified procedure. The power conversion efficiencies of 7.02 ± 0.18 % , comparable with Pt CE ( 7.84 ± 0.10 % ) could be routinely achieved. These results demonstrate a novel synthetic strategy to prepare layered TMDs with superior catalytic applications. [ABSTRACT FROM AUTHOR]

Neonatal spinal cord injury (SCI) is well described in the literature, though its diagnosis is often delayed or missed in the neonatal period. We present a neonate who was referred with upper gastrointestinal bleed and a diagnosis of spinal cord injury was subsequently made clinically and confirmed radiologically. [ABSTRACT FROM AUTHOR]

This study reports the prevalence of extended-spectrum β-lactamase producing Escherichia coli and Klebsiella spp among septicemic neonates. Over a five year period, there were 94 isolates of Klebsiella spp and E. coli. Of these, 68 (72.3%) were ESBL producers. Forty (80%) of the Klebsiella spp isolates produced ESBL as compared to 28 (63.6%) of E. coli. [ABSTRACT FROM AUTHOR]

The use of a central venous catheter may occasionally be associated with complications like sepsis, effusions and thrombosis. Migration of the central catheter is an unusual complication that often goes unrecognized. This case report is of a neonate who developed hydrothorax resulting from a migrating central line and highlights the need for a high level of clinical suspicion in diagnosing catheter related problems. [ABSTRACT FROM AUTHOR]

A modified technique for umbilical artery catheterization was assessed in babies in whom conventional method failed or if the cord was dry. Success rate attained with the modified technique was 90% (19/21). This modified technique could provide an easier and faster method for successful umbilical arterial catheterization. [ABSTRACT FROM AUTHOR]

The article discusses a case of an unusual patter of calcification in congenital toxoplasmosis in a preterm boy. A photograph of tomography of the brain is presented. A lateral skull radiograph photograph is also presented. The case could be attributed to intrauterine necrotizing meningoencephalitis.