Search

A search of dust structures nearby the pulsar J0302+2252 in IRIS, AKARI, and WISE surveys were performed using Skyview Observatory (http://skyview.gsfc.nasa.gov). The physical properties have been studied at 60µm & 100µm in the IRIS survey, 90µm & 140µm in the AKARI survey, and 12µm & 22µm in the WISE survey at right ascension (R.A.) (J2000)=03h 02m 31.99s and Declination (Decl.) (J2000)=+ 220 52m 12.10s . In this work, we have studied the physical properties such as Dust color temperature, Planck’s function, Visual extinction, and Mass profile of the dust using the data reduction software ALADIN v11. The dust color temperature is found to be 22.271 ± 0.261K in IRIS, 22.343 ± 0.939 K in AKARI, and 278.74 ± 0.067 K in WISE. Also, the dust mass is found to be 2.286 × 1027 kg (1.149 × 10-3 M⊙ ) in IRIS, 8.800 ×1026 kg (0.416× 10-3 M⊙ ) in AKARI and 5.220 ×1025 kg (0.026 ×10-3 M⊙ ) in WISE. The average visual extinction is found to be 1.372 ×10-13 mag. In IRIS, 4.970 ×10-14 mag. In AKARI and 1.673 ×10-15 mag. In WISE. The dust color temperature and dust mass distribution show a very good agreement with Gaussian. The Contour plots of dust color temperature and dust mass show inverse relation between them in all three bands IRIS, AKARI, and WISE.

The dust properties in the interstellar medium play an important role in structure formation and extinction of highenergy radiation. This study performed an investigation of the physical properties like distribution of dust color temperature, Planck’s function, and dust mass of the cavity around the pulsar PSR J1240-4124 in the IRIS and the AKARI surveys. In our study, the dust color temperature in the IRIS survey is found to be in the range of 23.607 ± 0.012 K to 24.342 ± 0.012 K with an offset of 0.735 K. Such low offset temperature indicates that the isolated cavities are in thermal equilibrium. In the case of the AKARI survey, the dust temperature was found to be in the range of 16.123 ± 0.017 K to 18.802 ± 0.017 K with an offset of 2.679 K. The average dust mass in IRIS survey is found to be 2.1 × 10−4 M⊙ and that of the AKARI is 8.1× 10−4 M⊙. The size of the structure in the IRIS map is 14.62 pc × 6.24 pc and that of the AKARI map is 5.80 pc × 0.17 pc. The angle of inclination for the selected cavity region is found to be 73.330° in IRIS and that of AKARI is 110.260° . We have tried to present the relationship among the different physical parameters and compare the results in the IRIS and the AKARI surveys. Our findings are similar to those obtained in previous studies of other cavity structures around pulsars. This confirms the validity of the existing results for a new cavity around PSR J1240-4124.

The objective of this research is to identify which Emerald Library Science journals and articles in the field of library and information science have received high altmetric attention scores and citation scores. The study examines all LIS journals indexed by the Dimensions database as of 2022.The findings of this study reveal that the Journal of Documentation is the top-ranked journal, with 24 articles that have the highest dimensions score of 3485, AAS score of 1159, Mendeley score of 3227, and an impact factor of 1.96 over the past five years. Notably, this study found that Mendeley (12150) and Twitter (2313) were the most frequently used altmetric sources. It is also worth mentioning that the highest altmetric attention scores were observed in document journals, with an altmetric score of 1159 indicating the level of attention these articles received. Researcher Subject Categories majority was the members of the public at 1727(17.26%). And highest geographical data access from the United States had the highest number of accesses with 315 (3.15%).

Potential live liver donors with non-alcoholic steatohepatitis (NASH) are rejected upfront for donation in live donor liver transplantation (LDLT). Herein, we share our experience of the feasibility of live liver donation in donors with NASH after successful donor optimization.Prospectively collected data of 410 consecutive donor hepatectomies from June 2011 to January 2018 were analyzed.During the study period, NASH was diagnosed histopathologically in 17 donors. Four donors were rejected in view of grade 2 fibrosis on histology. Out of remaining 13 donors, six became eligible for donation following lifestyle changes, dietary modifications, and target weight reduction of ≥5%. Reversal of NASH was confirmed on repeat liver biopsy in all the 6 donors. Five out of 6 underwent right lobe (without MHV) donor hepatectomies, while one had left lobe donation. These donors had significantly higher peak bilirubin levels in the immediate post-operative period as compared to other non-NASH donors (4.00 ± 0.32 vs. 2.57 ± 1.77 mg/dL, p = 0.043). In addition, post-hepatectomy normalization of hyperbilirubinemia, if any, was slower in donors with NASH (7 ± 1.3 vs. 5 ± 1.7 days, p = 0.016). However, none of these donors had post-hepatectomy liver failure. All these donors were discharged after an average hospital stay of 8 ± 1.7 days. Their respective recipients had uneventful post-operative courses without complications. Both the recipients and donors are having satisfactory liver functions after 46.7 ± 10.2 months of follow-up.Scrupulous selection of live liver donors with NASH can open a door for expanding the organ pool in LDLT after a successful donor optimization program.

Although over 180 freshwater fish species have been reported from Nepal, little is known of their ecology and distribution. This information is needed because their diversity may be threatened by developments like hydropower constructions. We conducted Nepal’s first environmental DNA (eDNA) based fish biodiversity assessment in two major river systems- Karnali River (KR), which is still pristine and Trishuli River (TR) with numerous hydropower plants. The eDNA was concentrated by filtering (0.45 μm pore size) two liters of water collected at different sampling points in each study site. A total of 224 eDNA samples (KR=162 and TR= 62) were collected, from which fish species was identified by 12S rRNA metabarcording approach utilizing Illumina sequencing platform. Alpha and beta diversity of species between two sites were compared. Also, in KR site, fish (N=795) were caught, and identified using COI based DNA barcoding- building Nepal’s first fish DNA reference database. Field sampling identified 21 species through morphology and DNA barcoding, where Barilius spp. and Schizothorax spp. were the most abundant. From 244 eDNA samples, 24 Operational Taxonomic Units (OTUs) were identified in TR and 46 in KR with 19 being common to both sites, 27 being unique in KR, and five in TR only. Most fishes were of Cypriniformes and Siluriformes orders, with Barilius spp. and Schizothorax spp. being the most abundant. Long distance migratory fish (Tor spp, Neolissochilus hexagonolepis) and non-native fish (Cyprinus carpio, Hypophthalmichthys molitrix, Gymnocorymbuster netzi, Ctenopharyngo donidella, Clarias gariepinus) were identified in eDNA samples as well. Alpha diversity in TR was significantly lower than in KR. High beta diversity between the two sites indicated low similarity in fish diversity between the TR and KR. This study demonstrated the utility of eDNA as a non-invasive technique for biodiversity assessment which is particularly useful in areas like Nepal with scarce data on fish species distribution.

Background: Megaloblastic anaemia during metformin therapy can be treated by administrating vitamin B12. 10-30% of diabetic patients on long term treatment with metformin had vitamin B12 deficiency. Objective: To determine VitaminB12 deficiency in type2 diabetes patients on long term metformin therapy for >2years. Materials & Methods: This prospective study carried out in Department of Medicine in Dr DY Patil Medical College and Hospital, Pune. It was comparison between 50 cases and 50 controls to find Vitamin B12 Deficiency In Type 2 Diabetes Patients On Long Term Metformin Therapy For >2years. Results: Mean age was for cases was 47.12 + 12.54 years and for controls was 41.64 + 9.74 years with majority in the age group of 41 to 60 years among both groups. Among cases males 52% were more than females 48%. Mean weight was for cases was 70.72 + 11.6 kg and controls was 58.02 + 6.80 kg. Mean BMI was for cases was 27.36 + 4.88 and controls was 23.93 + 2.71 and majority were in range of 25 to 30. Common symptoms seen were Polyuria and polydipsia. 50% had HTN. Majority were smokers followed by alcoholic. Mean duration of DM among cases was 6.18 + 2.64years. Mean serum vitamin B12 of cases was 271.75 + 184.21 and controls were 410.45 + 154.34, showed statistical significance. Majority among cases had Vit B12 levels lower than 200 and controls were more than 301. P value was highly significant. Conclusion: Routine supplementation of vitamin B12 given to patients on long-term high dose metformin therapy seems to be clinically more prudent and a costeffective approach

Background Excessive and irrational use of antibiotics as growth promoters in poultry has been one of key factors contributing to increased emergence of antibiotics resistant bacteria. Several alternatives for antibiotic growth promoters are being sought, and the search for effective probiotics to be used as feed additives is amongst the promising ones. Our study aimed to isolate and test potential probiotics bacteria from cloacal swabs of various indigenous chicken (Gallus domesticus) breeds from rural outskirts of the Kathmandu valley (Nepal). Methods Selective isolation of probiotics was conducted by micro-aerophilic enrichment of sample in MRS Broth at 37°C, followed by culturing on MRS agar supplemented with 5 g/L of CaCO3. Isolated bacterial colonies producing transparent halo were selected as potential lactic acid bacteria (LAB), and tested for their antibacterial activity, phenotypic and biochemical characteristics, acidic yield, and tolerance to acid and bile. Results A total of 90 potential LAB were isolated from cloacal samples collected from 41 free-ranging chickens of indigenous breeds. Of these, 52 LAB isolates (57%) showed variable antibacterial activity to at least one bacterial pathogen. Of 52 LAB, 46 isolates fulfilled phenotypic and biochemical criteria of Lactobacillus spp. Of these, 37 isolates produced varying percentage yields of lactic acid, 27 isolates showed survival at pH 3.0, and 17 isolates showed survival tolerances in the presence of 0.3% and 0.5% bile salts for 24 hours. Phylogenetic analysis of 16S rDNA sequencing of LAB isolates fulfilling in vitro probiotics properties showed that 3 isolates had genetic identity of 99.38% with Lactobacillus plantarum, while one isolate was genetically similar (99.85%) with the clade of L. reuteri, L. antri and L. panis. Conclusion Our study identified four Lactobacillus spp. strains having potential probiotics properties. Further investigations are needed to evaluate these isolates to be used as poultry probiotics feed supplement.

We are presenting the non-aqueous emulsions comprising of liquid crystal 8CB (4′-Octyl-4-biphenylcarbonitrile) and silicone oil in varying ratios (5:95, 10:90, 25:75 and 50:50 wt./wt.%). Emulsions ...

BACKGROUND Sepsis is common in cirrhosis and is often a result of immune dysregulation. Specific stimuli and pathways of inter-cellular communications between immune cells in cirrhosis and sepsis are incompletely understood. Immune cell-derived extracellular vesicles (EV) were studied to understand mechanisms of sepsis in cirrhosis. METHODS Immune cell-derived EV were measured in cirrhosis patients [Child-Turcotte-Pugh (Child) score A, n = 15; B n = 16; C n = 43 and Child-C with sepsis (n = 38)], and healthy controls (HC, n = 11). In vitro and in vivo functional relevance of EV in cirrhosis and associated sepsis was investigated. RESULTS Monocyte, neutrophil and hematopoietic stem cells associated EV progressively increased with higher Child score (P 0.3, P

Functional nanocomposites are designed via doping ferroelectric liquid crystal (FLC) matrix by 0.03wt% and 0.1wt% of functionalised multiwall carbon nanotubes (MWCNTs). Mesomorphic, optical, thermo...

Background: Mitral regurgitation (MR) is commonly encountered in patients with severe aortic stenosis (AS). However, its independent impact on mortality in patients undergoing transcatheter aortic valve implantation (TAVI) has not been established. Methods: We performed a systematic search for studies reporting characteristics and outcome of patients with and without significant MR and/or adjusted mortality associated with MR post-TAVI. We conducted a meta-analysis of quantitative data. Results: Seventeen studies with 20,717 patients compared outcomes and group characteristics. Twenty-one studies with 32,257 patients reported adjusted odds of mortality associated with MR. Patients with MR were older, had a higher Society of Thoracic Surgeons score, lower left ventricular ejection fraction, a higher incidence of prior myocardial infarction, atrial fibrillation, and a trend towards higher NYHA class III/IV, but had similar mean gradient, gender, and chronic kidney disease. The MR patients had a higher unadjusted short-term (RR = 1.46, 95% CI 1.30–1.65) and long-term mortality (RR = 1.40, 95% CI 1.18–1.65). However, 16 of 21 studies with 27,777 patients found no association between MR and mortality after adjusting for baseline variables. In greater than half of the patients (0.56, 95% CI 0.45–0.66) MR improved by at least one grade following TAVI. Conclusion: The patients with MR undergoing TAVI have a higher burden of risk factors which can independently impact mortality. There is a lack of robust evidence supporting an increased mortality in MR patients, after adjusting for other compounding variables. MR tends to improve in the majority of patients post-TAVI.

As SARS-CoV-2 variants emerge, there is a critical need to understand the effectiveness of serum elicited by different SARS-CoV-2 vaccines. A reference reagent comprised of post-vaccination sera from recipients of different vaccines allows evaluation of in vitro variant neutralization, and provides a reference for comparing assay results across laboratories. We prepared and pooled >1 L serum from donors who received the SARS-CoV-2 mRNA vaccines (BNT162b2, Pfizer and mRNA-1273, Moderna), a replication-incompetent adenovirus type 26 vaccine (Ad26.COV2.S, Johnson and Johnson), or recombinant spike protein expressed by baculovirus incorporated into a nanoparticle vaccine plus Matrix-M adjuvant (NVX-CoV2373, Novavax). Twice frozen sera were aliquoted and are available for distribution to the research community (BEI Resources). The calculated WHO titer of pooled sera to spike protein was 1,312, 1,447, 1,936, and 587 and the reciprocal RBD binding to ACE-2 IC90-titers were 60, 64, 118, and 46 for BNT162b2, mRNA1273, Ad26.CoV2373, and NVX-CoV2373 sera, respectively.

OBJECTIVE The purpose of this study is to assess the utility of ambulatory cardiac monitoring (ACM) in detecting delayed advanced conduction abnormalities (DACA) and associated 30-day mortality. BACKGROUND DACA are well-known complications of TAVR and may be associated with post-discharge mortality within 30-days. METHODS Between October 2019 and October 2020, TAVR patients who were discharged home without a permanent pacemaker (PPM) were monitored with an ACM device for 14-days. The incidence of DACA at follow up, mortality and readmission within 30-days were investigated. The risk of DACA was assessed in three patient categories based on a composite of their 12-lead electrocardiogram (ECG) data. Group I: Normal pre-TAVR, periprocedural, and discharge ECGs. Group II: Normal pre-TAVR and abnormal subsequent ECGs. Group III. Abnormal baseline and abnormal subsequent ECGs. RESULTS Among 340 TAVR patients, 248 were discharged home with an ACM device. The overall incidence of DACA was 7% (n = 17), of whom 4% (n = 10) required a PPM. Mortality and readmission between discharge and 30 days was 0% and 8.3%, respectively. Stratification of patients identified 96 (38.7%) patients in Group I: 50 (20%) in Group II, and 102 (41%) in Group III. The incidence of DACA requiring a PPM was 0% in Group I, 4% (n = 2) in Group II, and 8.5% (n = 8) in Group III (p

This paper presents the case of a 67-year-old female with primum atrial septal defect and congenital mitral cleft status-post surgical repair 40 years previously who was recently found to have severe mitral regurgitation. Percutaneous mitral valve repair was successfully performed using implantation of 2 MitraClips with mild residual mitral regurgitation. (Level of Difficulty: Advanced.), Graphical abstract

Critical illness myopathy (CIM), critical illness polyneuropathy (CIP), and critical illness polyneuromyopathy (CIPNM) are the group of disorders that are commonly presented as neuromuscular weakness in intensive care unit (ICU) settings. They are responsible for prolonged ICU stay and failure to wean off from mechanical ventilation. We report a case of young female who was admitted with undiagnosed type I diabetes mellitus with diabetic ketoacidosis, severe hypokalemia, sepsis developed acute onset quadriplegia, and diaphragmatic palsy within 72 hours of ICU admission. On detailed investigation, CIPNM was diagnosed. In view of high morbidity, mortality, and poor prognosis, a guided approach to diagnose and treat in earliest possible duration might give better improvement and outcome of the illness. Despite all the odds, our patient showed good clinical improvement and finally got discharged. How to cite this article Mahashabde M, Chaudhary G, Kanchi G, Rohatgi S, Rao P, Patil R, et al. An Unusual Case of Critical Illness Polyneuromyopathy. Indian J Crit Care Med 2020;24(2):133–135.

Understanding disease burden and transmission dynamics in resource-limited, developing countries like Nepal is often challenging due to a lack of adequate surveillance systems. These issues are exacerbated by limited access to diagnostic and research facilities throughout the country. Nepal has one of the highest COVID-19 case rates (915 cases per 100,000 people) in South Asia, with densely-populated Kathmandu experiencing the highest number of cases. Swiftly identifying case clusters and introducing effective intervention programs is crucial to mounting an effective containment strategy. The rapid identification of circulating SARS-CoV-2 variants can also provide important information on viral evolution and epidemiology. Genomic-based environmental surveillance can help in the early detection of outbreaks before clinical cases are recognized, and identify viral micro-diversity that can be used for designing real-time risk-based interventions. This research aimed to develop a genomic-based environmental surveillance system by detecting and characterizing SARS-CoV-2 in sewage samples of Kathmandu using portable next-generation DNA sequencing devices. Out of 20 selected sites in the Kathmandu Valley, sewage samples from 16 (80%) sites had detectable SARS-CoV-2. A heat-map was created to visualize transmission activity in the community based on viral load intensity and corresponding geospatial data. Further, 41 mutations were observed in the SARS-CoV-2 genome. Some detected mutations (n=9, 2%) were novel and yet to be reported in the global database, with one indicating a frameshift deletion in the spike gene. We also observed more transition than transversion on detected mutations, indicating rapid viral evolution in the host. Our study has demonstrated the feasibility of rapidly obtaining vital information on community transmission and disease dynamics of SARS-CoV-2 using genomic-based environmental surveillance.

Transcatheter Aortic Valve Replacement (TAVR) remains a complex procedure with the potential for life-threatening complications including heart block, bleeding from vascular access sites, and peric...

IntroductionThere is limited data on clinical course and outcomes of hospitalized adults with COVID-19 in Nepal. Thus, it is imperative to characterize the features of this disease in the domestic context.MethodologyWe identified all adult patients with laboratory-confirmed COVID-19 admitted to five different hospitals in Nepal from June 15 to July 15, 2020. We collected epidemiological, socio-cultural and clinicopathologic data, and stratified the patients based on their symptom status.ResultsThe study included 220 patients with an overall median age of 31.5 (25-37) years, and 181 (82.3%) were males. 159 (72.3%) were asymptomatic, and 163 (74.1%) were imported cases. Of 217 patients with the available data, 110 (50.7%) reported their annual household income less than 2000 US dollars, and 122 (56.2%) practiced Pranayama (yogic rhythmic breathing techniques) regularly. Eight patients (3.6%) required supplemental oxygen and two patients (0.9%) died. None of the patients who practiced Pranayama regularly required supplemental oxygen. Compared to asymptomatic patients, symptomatic patients had greater proportion of females (31.1% vs. 12.6%, p=0.001), imported cases (85.2% vs. 69.8%, p=0.02), illiterates (26.8% vs. 12.1%, p=0.01), alcohol users (43.3% vs. 24.5%, p=0.01), patients feeling stigmatized by society (45.8% vs. 22.6%, p=0.001), and had higher platelet count (253× 109/L vs. 185×109/L, p=0.02).ConclusionsMost cases were imported, asymptomatic young males, with very few deaths. Pranayama practice was associated with protection against severe COVID-19, but more data is needed to substantiate this. The association of platelets count with symptom status in the Nepalese population needs further exploration.

Background: Health care workers are at greater risk of infection during COVID 19 pandemic. This study was carried out to assess the knowledge and attitude toward COVID-19 among healthcare workers at working at Seti Zonal Hospital. Methods: A cross-sectional study was performed between April and May 2020 at Seti Zonal Hospital with purposive sampling technique and self-administered questionnaire of the knowledge and attitude of healthcare workers regarding COVID-19. The demographic characteristics mean knowledge and attitude score of healthcare workers were identified and inferential statistics t-test, ANOVA and Spearman’s correlation were used to show the relationship between variables. Results: A total of 230 healthcare workers (92% response rate) had a mean score of knowledge and attitude of 8±0.88 and 7.88±1.32, respectively with good knowledge and a low positive attitude. Majority (94.7%) were familiar with the sign and symptoms, agreed that chronic diseases patients and HCWs are at a higher risk (97%) and (87.8%) respectively while knowledge related to COVID 19 vaccination, isolation period and treatment by antibiotics was poor with low positive attitude towards information availability about COVID 19 (41%), government ability to control the epidemic (49%), and the family members might get infection (60%). There was a positive correlation between knowledge scores and attitude scores (r=0.28, p

BackgroundThere are apprehensions amongst healthcare worker (HCWs) about COVID-19. The HCWs have been given hydroxychloroquine (HCQ) chemoprophylaxis for seven weeks as per Government of India guidelines.ObjectivesTo assess the apprehensions amongst HCWs about COVID-19 and to document accessibility, adherence and side effects related to HCQ prophylaxis in HCWs.MethodsA longitudinal follow up study was conducted in a tertiary care hospital. HCQ was given in the dose of 400 mg twice on day one, and then 400 mg weekly for seven weeks. 391 HCWs were interviewed using semi structured questionnaire.Results62.2% HCWs expressed perceived danger posted by COVID-19 infection. Doctors (54%) showed least acceptance and paramedics (88%) showed highest acceptance to chemoprophylaxis. 17.5% participants developed at least one of the side effects to HCQ. Females and nursing profession were significantly associated with adverse effects. Common side effects were gastro-intestinal symptoms, headache and abnormal mood change. Most of these were mild, not requiring any intervention. Gender, professions and perceived threat of COVID-19 were significantly associated with acceptance and adherence to HCQ prophylaxis.ConclusionTwo third of HCWs had perceived danger due to COVID-19. Three fourth of the HCWs accepted chemoprophylaxis and four out of five who accepted had complete adherence to prophylaxis schedule. One out of five had developed at least one of side effects; however, most of these were mild not requiring any intervention.

BACKGROUND There are apprehensions among healthcare worker (HCWs) about COVID-19. The HCWs have been given hydroxychloroquine (HCQ) chemo-prophylaxis for seven weeks as per Government of India guidelines. OBJECTIVE To assess the apprehensions among HCWs about COVID-19 and to document accessibility, adherence and side effects related to HCQ prophylaxis in HCWs. METHODS A longitudinal follow up study was conducted in a tertiary care hospital. HCQ was given in the dose of 400 mg twice on day one, and then 400 mg weekly for seven weeks. 391 HCWs were interviewed using semi structured questionnaire. RESULTS 62.2% HCWs expressed perceived danger posted by COVID-19 infection. Doctors (54%) showed least acceptance and paramedics (88%) showed highest acceptance to chemo-prophylaxis. 17.5% participants developed at least one of the side effects to HCQ. Females and nursing profession were significantly associated with adverse effects. Common side effects were gastro-intestinal symptoms, headache and abnormal mood change. Most of these were mild, not requiring any intervention. Gender, professions and perceived threat of COVID-19 were significantly associated with acceptance and adherence to HCQ prophylaxis. CONCLUSIONS Two third of HCWs had perceived danger due to COVID-19. Three fourth of the HCWs accepted chemo-prophylaxis and four out of five who accepted had complete adherence to prophylaxis schedule. One out of five had developed at least one of side effects; however, most of these were mild not requiring any intervention.

The clinical course of COVID-19 can get complicated by a wide range of neurological as well as thromboembolic incidents. Despite numerous guidelines recommending the use of thromboprophylaxis in hospitalized patients, the compliance to it is poor, especially in developing countries. We report a case of an adult with severe COVID-19 whose clinical course was complicated by a sudden onset weakness and loss of sensation in his right upper extremity, with concomitant new onset blackish discoloration of one of his fingernails. This was accompanied by a significant decrease in platelet count when compared to his baseline. Based on clinical grounds, the diagnosis of ischemic brachial plexopathy was made after which the patient was started on low molecular weight heparin. Our case highlights the importance of strictly adhering to the recommendations on thromboprophylaxis, which might have averted this unfortunate incident had we followed it in our patient since his admission.

We report the effect of oblique irradiation of thin As2S3 chalcogenide glass films on the photoalignment of Nematic liquid crystals and their electro optical properties. After depositing 60 nm As2S3 films on ITO coated substrates, the substrates were irradiated with polarized blue light (436 nm) at angles 0°, 5°, 20° and 48° of the light propagation direction with respect to the substrate plane. Then, the substrates were assembled and filled with the liquid crystal. The device LC-20° exhibits good extinction, and lower threshold voltage when compared to all other devices. The contrast ratio of LC-20° almost double that of the LC-5° and LC-48° devices. The response time increases with the angle, so for LC-20° slightly longer than for LC-5° but shorter than that of LC-48°. It is evident from the observations that the obliquely irradiated cells show good photoalignment and enhanced electro optical properties, although no pretilt is generated due to the oblique irradiation. Therefore, contrary to the photoalignment using photosensitive polymers, chalcogenide glasses have the advantage of providing photoalignment with little sensitivity to the irradiation angle. This fact led us to propose a model for the photoinduced alignment on chalcogenide glasses based on directional structural changes, not related to oriented dipoles generation as in the case of photoalignment with polymers.

The polar anchoring energy of nematic liquid crystals on nanodimensional films of chalcogenide glasses irradiated with linearly polarized visible light is measured using the optical retardation at high electric field method. It is found that the polar anchoring energy is increasing with irradiation time and comparable to that reported using other UV photoalignment polymers. Together with the fact that this is a solid transparent photoalignment layer, can be deposted in large area and on curved surfaces, photoconductive, and can be patterned, the hybrid liquid crystal devices have a great potential in displays and other photonic applications.

Nanocomposites comprise functionalised multi-walled carbon nanotubes (0.00 wt%, 0.05 wt% and 0.07 wt%) and ferroelectric liquid crystals (FLCs) have been studied in the 5-μm- and 12-μm-thickness ce...

Liquid crystal/silicone oil based emulsions have been prepared and characterized for interfacial interactions, optical and electro-optical behaviour. Emulsions are stabilized without any surface-active agent via non-covalent interactions, surface alignment and anchoring conditions. Emulsions are characterized by polarizing optical microscopy. Distinct mesomorphic phases, droplet geometries (radial, hedgehog, bipolar) and transitions viz. radial to bipolar and bipolar to broken bipolar are observed as a function of varying silicone oil concentration in liquid crystal. These emulsions are quite stable and show reversible characteristics as a function of time and temperature. The stability of these emulsions has been explained considering hydrophobic interactions, decrease in internal surface tension and anchoring energy etc. Further, the liquid crystal/silicone oil devices have been fabricated and tested for switching and electro-optical behaviour. The emulsion contains 25% silicone oil in liquid crystal matrix shows the best switching characteristics at low deriving voltage 5 V, about 87% enhancement in optical transmission, 8.3 dB contrast and lower Frederiks threshold ~65%. Such switchable and optically tuneable surfactant-free emulsions with controlled morphological dynamics can provide a new door to design novel functional soft material platform for better optical, electro-optical, photonics, sensing and liquid crystals elastomer applications.

The results of high-resolution x-ray reflectivity study of nano-dimensionally thin arsenic trisulfide (As2S3) glass films reveal surface roughness anisotropy upon prolonged irradiation with polarized 436 nm blue light. The anisotropy correlates with the photoinduced anisotropy and LC photoalignment observed on these thin films. However, the As2S3 film's thickness reduces drastically during the reflectivity experiments, and ambient oxygen and moisture penetrate the film and create a second altered thin layer on top of a thicker film of As2S3. The results confirm the viability of As2S3 films for non-contact LC photoalignment material but suggests the need for further process optimization to reduce the films' degeneration to increase their effectiveness.

Lead sulphide (PbS) nano-sculptured thin films (nSTFs) are prepared for the first time using glancing angle deposition technique by physical vapour deposition process. An anisotropic morphology is ...