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We report temperature-dependent dielectric permittivity, thermal conductivity and mechanical resonances of as-grown hybrid perovskite single crystal CH 3 NH 3 PbBr 3 . Structural phase transitions are analysed using new experimental techniques, where thermal conductivity by steady-state process and elastic modulai by ultra-resonance spectroscopy is carried out through [100] and [110] directions, respectively. Performing thermal conductivity measurement on small-sized samples usually pose a significant challenge due to its dimensional limit. Following the steady-state technique, we measured the thermal conductivity of around 1 W m −1 K −1 in the temperature range 100–300 K on 2 × 2 mm 2 size crystal. This is found to be comparable with I +3 anion-based hybrid perovskites as reported by Pisoni et al 2014 J. Phys. Chem. Lett. 5 2488. Room temperature electrical resistivity and dielectric permittivity of order 10 9 and 10 2 , respectively, shows sharp transitions while approaching 150 K, which strongly supports first-order structural transition. Thermally activated resistivity behaviour above 280 K follows 1/ T dependence, yielding activation energy of 0.2 eV. Softening of elastic moduli on approaching the phase transition is analysed from resonant ultrasound spectroscopy measurement. Square of the resonance frequency is found to diverge below 236 K, which inhibits any further experimental determination of elastic moduli at low temperature.

Over the past three decades, management of blunt splenic trauma has changed radically. Use of improved diagnostic techniques and proper understanding of disease pathology has led to nonoperative management being chosen as the standard of care in patients who are haemodynamically stable. This review was undertaken to assess available literature regarding changing trends of management of blunt splenic trauma, and to identify the existing lacunae in nonoperative management. The PubMed database was searched for studies published between January 1987 and August 2017, using the keywords ‘blunt splenic trauma’ and ‘nonoperative management’. One hundred and fifty-three articles were reviewed, of which 82 free full texts and free abstracts were used in the current review. There is clear evidence in published literature of the greater success of nonoperative over operative management in patients who are haemodynamically stable and the increasing utility of adjunctive therapies like angiography with embolisation. However, the review revealed a lack of universal guidelines for patient selection criteria and diagnostic and grading procedures needed for nonoperative management. Indications for splenic artery embolisation, the current role of splenectomy and spleen-preserving surgeries, together with the place of minimal access surgery in blunt splenic trauma remain grey areas. Moreover, parameters affecting the outcomes of nonoperative management and its failure and management need to be defined. This shows a need for future studies focused on these shortcomings with the ultimate aim being the formulation and implementation of universally accepted guidelines for safe and efficient management of blunt splenic trauma.

Flow separation over a 3D wing, both local at low angles of attack and that which begins at a section and then engulfs the entire wing at the higher angles of attack is studied using experiments and CFD. The pressure measured from pressure ports located on the root section of the 3D wing is used to calculate the pressure coefficient and oil flow visualization conducted to study separation lines. The location and length of the separated zone along wing-span is calculated. Statistical analysis of the data extracted from the oil flow visualization is used to generate curve-fit separation and reattachment lines. The data shows lines to be third-order polynomial. Study indicates that the location of laminar separation bubbles is more sensitive to the angle of attack as compared to the Reynolds number. At the higher angles of attack, the effect of the Reynolds number and the angle of attack on stall progression is studied. The velocity profile in the boundary layer at five different locations along wing-span is calculated at the angles of attack near complete wing stall. Sections near wing-root and the wing tips are studied in detail and inferences drawn on stall progression in cambered wing. A comprehensive study of flow separation and laminar separation bubble on a 3D wing can be used as basis of design for active flow control.

Despite known health disparities in cognitive aging, a comprehensive rationale for the increased burden in older minoritized populations including non-Latino Black and Latino adults has yet to be elucidated. While most work has focused on person-specific risk, studies are increasingly assessing neighborhood-level risk. We evaluated multiple aspects of the environmental milieu that may be critical when considering vulnerability to adverse health outcomes. We investigated associations between a Census-tract derived Social Vulnerability Index (SVI) and level of and change in cognitive and motor functioning in 780 older adults (590 non-Latino Black adults, ∼73 years old at baseline; 190 Latinos, ∼70 years old baseline). Total SVI scores (higher = greater neighborhood-level vulnerability) were combined with annual evaluations of cognitive and motor functioning (follow-up ranged from 2 to 18 years). Demographically-adjusted mixed linear regression models tested for associations between SVI and cognitive and motor outcomes in analyses stratified by ethno-racial group. For non-Latino Black participants, higher SVI scores were associated with lower levels of global cognitive and motor functioning-specifically, episodic memory, motor dexterity and gait-as well as longitudinal change in visuospatial abilities and hand strength. For Latinos, higher SVI scores were associated with lower levels of global motor functioning only-specifically, motor dexterity; there were no significant associations between SVI and change in motor functioning. Neighborhood-level social vulnerability is associated with cognitive and motor functioning in non-Latino Black and Latino older adults, although associations appear to contribute to level more so than longitudinal change.

This is the first study aimed at objectively quantifying the benefit of virtual education using WhatsApp-based discussion groups. A prospective, non-randomised interventional study was undertaken in the Department of General Surgery, at a tertiary care centre in Kolkata, India, with 200 undergraduate students over a period of 5 days each for 2 weeks, with the first week acting as a control arm. A WhatsApp group was created consisting of 197 eligible undergraduates, faculty members and the authors of this study. Each day, three questions were posted on this group. The second week involved an hour-long WhatsApp-based discussion between the participants and the faculty. Responses were recorded and compared for improvements between the two weeks. Participant feedback was collected and analysed. Statistically significant improvements were observed in the study group compared with the control group in rates of one in three, two in three and three in three correct responses ( =0.01649, 0.01146 and 0.00946, respectively). A total of 68 (51.92%) feedback respondents were satisfied with the programme. Convenience of use was the principal reason behind satisfaction in 79 respondents (60.31%), whereas 62 participants (47.33%) reported lack of hands-on training as a major drawback. WhatsApp was found to be a satisfactory supplement to traditional medical teaching. It can be implemented to fill lapses in medical education, especially in light of the COVID-19 pandemic, which has caused great disruption to traditional teaching methods. Research is needed to assess the feasibility of incorporating it into the curriculum.

High angular resolution observations at optical wavelengths provide valuable insights into stellar astrophysics 1 , 2 , and enable direct measurements of fundamental stellar parameters 3 , 4 and the probing of stellar atmospheres, circumstellar disks 5 , the elongation of rapidly rotating stars 6 and the pulsations of Cepheid variable stars 7 . The angular size of most stars is of the order of one milliarcsecond or less, and to spatially resolve stellar disks and features at this scale requires an optical interferometer using an array of telescopes with baselines on the order of hundreds of metres. We report on the implementation of a stellar intensity interferometry system developed for the four VERITAS imaging atmospheric Cherenkov telescopes. The system was used to measure the angular diameter of the two sub-milliarcsecond stars β Canis Majoris and ϵ Orionis with a precision of greater than 5%. The system uses an offline approach in which starlight intensity fluctuations that are recorded at each telescope are correlated post observation. The technique can be readily scaled onto tens to hundreds of telescopes, providing a capability that has proven technically challenging to the current generation of optical amplitude interferometry observatories. This work demonstrates the feasibility of performing astrophysical measurements using imaging atmospheric Cherenkov telescope arrays as intensity interferometers and shows the promise for integrating an intensity interferometry system within future observatories such as the Cherenkov Telescope Array. Stellar intensity interferometry (SII) is undergoing a revival. Here, data from the four 12 m optical reflectors of the VERITAS array are correlated post facto to determine the angular diameter of two stars to a high precision, laying the groundwork for SII at future large Cherenkov arrays.

Acetaminophen (N-acetyl-para-aminophenol (APAP)) toxicity causes acute liver failure by inducing centrilobular hepatic damage as a consequence of mitochondrial oxidative stress. Sterile inflammation, triggered by hepatic damage, facilitates gut bacterial translocation leading to systemic inflammation; TLR4-mediated activation by LPS has been shown to have a critical role in APAP-mediated hepatotoxicity. In this study, we demonstrate significant protection mediated by chitohexaose (Chtx) in mice challenged with a lethal dose of APAP (400 mg/kg b.w.). Decreased mortality by Chtx was associated with reduced hepatic damage, increased peritoneal migration of neutrophils, decreased mRNA expression of IL-1 β as well as inhibition of inflammasome activation in liver. Further, an alternate mouse model of co-administration of a sublethal doses of APAP (200 mg/kg b.w.) and LPS (5 mg/kg b.w.) operating synergistically and mediating complete mortality was developed. Overwhelming inflammation, characterized by increased inflammatory cytokines (TNF- α , IL-1 β and so on) in liver as well as in circulation and mortality was demonstrable in this model. Also, Chtx administration mediated significant reversal of mortality in APAP+LPS co-administered mice, which was associated with reduced IL-1 β in liver and plasma cytokines in this model. In conclusion, Chtx being a small molecular weight linear carbohydrate offers promise for clinical management of liver failure associated with APAP overdose.

The main cause of prostate cancer-related mortality is the development of hormone-refractory disease. Circulating serum levels of IL-6 are raised in hormone-refractory prostate cancer patients and evidence from cell line studies suggests that the IL-6R/JAK/STAT3 pathway may be involved in development of this disease. In the current study we investigate if expression levels of these family members are implicated in the development of hormone-refractory prostate cancer. Immunohistochemistry using IL-6R, JAK1, STAT3, pSTAT3 Tyr705 and pSTAT3 Ser727 antibodies was performed on 50 matched hormone-sensitive and hormone-refractory tumours pairs. An increase in expression of cytoplasmic IL-6 receptor, with the development of hormone-refractory prostate cancer was associated with reduced time to relapse ( P =0.0074) while an increase in expression of cytoplasmic pSTAT3 Tyr705 was associated with reduced patient survival ( P =0.0003). In addition, those patients with high expression of cytoplasmic pSTAT3 Tyr705 in their hormone-refractory tumours had significantly shorter time to death from biochemical relapse and overall survival in comparison to those patients with low expression of cytoplasmic pSTAT3 Tyr705 ( P =0.002 and P =0.0027, respectively). Activation of STAT3, via phosphorylation is associated with reduced patient survival, suggesting that activation of the IL-6R/JAK/STAT3 pathway is involved with development of hormone-refractory prostate cancer.

Orbit of a single particle moving under the Yukawa potential is studied and there exists precessing ellipse type orbits. The amount of precession can be tuned through the coupling parameter α. With a suitable choice of the coupling parameter; we get a closed bound orbit. In some cases few petals are observed which is possessed of a closed bound nature for suitably chosen coupling parameter. Threshold energy has also been calculated for bound orbits.

Background: Recent evidence has implicated the MAP kinase (MAPK) pathway with the development of castrate-resistant prostate cancer (CRPC). We have previously reported gene amplification of critical members of this pathway with the development of castrate-resistant disease. In addition, we have shown that rising Raf-1 expression, with the development of CRPC, influences time to biochemical relapse. We therefore sought to further analyse the role of both Raf-1 and its downstream target MAPK in the molecular pathogenesis of CRPC. Methods: Protein expression of Raf-1 and MAPK, including their activation status, was analysed using immunohistochemistry in a database of 65 paired tumour specimens obtained before and after the development of CRPC and correlated with other members of the pathway. Results: Patients whose nuclear expression of MAPK rose with the development of CRPC had a significantly shorter median time to death following biochemical relapse (1.40 vs 3.00 years, P =0.0255) as well as reduced disease-specific survival when compared with those whose expression fell or remained unchanged (1.16 vs 2.62 years, P =0.0005). Significant correlations were observed between protein expression of Raf-1 and MAPK with the type 1 receptor tyrosine kinases, Her2 and epidermal growth factor receptor, as well as the transcription factor AP-1 in CRPC tumours. Conclusion: We conclude that the Her2/Raf-1/MAPK/AP-1 axis may promote the development of CRPC, leading to early relapse, and reduced disease-specific survival. In addition, members of the pathway may act as novel therapeutic and/or diagnostic targets for prostate cancer.