Scattering in a varying mass PT symmetric double heterojunction

We observe that the reflection and transmission coefficients of a particle within a double, PT symmetric heterojunction with spatially varying mass, show interesting features, depending on the degree of non Hermiticity, although there is no spontaneous breakdown of PT symmetry. The potential profile in the intermediate layer is considered such that it has a non vanishing imaginary part near the heterojunctions. Exact analytical solutions for the wave function are obtained, and the reflection and transmission coefficients are plotted as a function of energy, for both left as well as right incidence. As expected, the spatial dependence on mass changes the nature of the scattering solutions within the heterojunctions, and the space-time (PT) symmetry is responsible for the left-right asymmetry in the reflection and transmission coefficients. However, the non vanishing imaginary component of the potential near the heterojunctions gives new and interesting results.Comment: 7 pages, 8 figure

Correlation of “Disc Damage Likelihood Scale” with field defects in established Glaucomas: An Anatomical Versus Functional correlation

AIM OF THE STUDY: To analyse Disc Damage likelihood ratio in patients with established open angle glaucoma and to correlate it with field defects and to thereby obtain an anatomical versus functional correlation. This study also evaluates the diagnostic ability of disc damage likelihood scale in glaucoma. MATERIALS AND METHODS: 50 cases of established open angle glaucoma were included in this study. Patients more than 45 yrs, BCVA more than 6/36, with open angles were included. Other causes of optic neuropathy, angle closures, BCVA less than 6/36, patients operated less than a year were excluded. All of the cases underwent detailed anterior segment examination, fundus examination. Visual fields were recorded by Octopus 301 using G1 program and TOP strategy. After field testing, DDLS scores were calculated after dilataion with tropicamide. The DDLS score and field parameters of the patients were analysed. RESULTS: Of the 50 patients included in this study, 30% were in the age group of 45-50 yrs and 24% were aged more than 66 years. 62% were male patients and 38% were female patients. 70% were on topical antiglaucoma medications and 30% had undergone trabeculectomy. The average vertical disc diameter was 1.86 mm. Among the 50 patients, 4 patients had asymmetry of disc diameter between the right and left eye. The cup disc ratio in all four patients showed significant asymmetry, of more than 0.2. But the DDLS score in both the eyes in all four patients were the same. DDLS score and average loss variance showed a strong positive correlation as the r value was 0.95. CONCLUSION: Disc diameter evaluation is an important part of optic nerve head evaluation. In cases with asymmetry of the cup disc ratio between two eyes, asymmetry of the disc size should also be considered if the neuroretinal rim is healthy. Disc Damage Likelihood Scale (DDLS) is a better indicator of optic nerve head status and has strong positive correlation with visual field indices

Rooting of flowering Dogwood (Cornus florida) microshoots

Before flowering dogwood (Cornus florida L.) can be commercially propagated by tissue culture methods, a reliable and efficient method of production must be developed. Cornus florida has been micropropagated successfully but with a low rooting efficiency of about 50 %. Rooting has been a major problem in tissue culture of many other plants as well. This study was conducted to increase rooting efficiency of flowering dogwood microshoots over that previously achieved. Five to six week old microshoots originating from acclimatized axillary and nodal bud stock cultures were excised and used in the rooting experiments. Cornus florida microshoots were treated with various root promoting substances and bacteria. Microshoots were dipped for 24 h in aqueous diffiisates that were prepared by leaching stem cuttings of either black locust (Robinia pseudoacacia L.) or contorted willow (Salix x erythroflexuosa Rag.). Explants were then transferred to Woody Plant Medium (WPM) with and without indole-3-butyric acid (IBA). Various concentrations of salicylic acid and acetylsalicylic acid as root stimulating moeities were tested as a continuous exposure and a 24 h pulse treatments. A recently discovered root stimulating bacterium (RSB) promoted rooting in Pinus seedlings was also used to study rooting of flowering dogwood microshoots. Microshoots were treated with RSB cells as well as extracts obtained at pH 3 and pH 7 from the spent medium in which RSB was grown. Rooting efficiencies of microshoots grown on WPM and treated with these root promoting substances, bacterium and bacterial culture extracts were compared to that of microshoots grown on WPM with 4.9 µM IBA. Microshoots formed roots in all the experiments. Locust and willow diffusate slightly inhibited root formation on microshoots. Continuous exposure to 100 µM salicylic acid and 50 and 100 µM acetylsalicylic acid promoted root generation but not significantly different from that achieved with IBA. The highest mean number of roots/explant were produced when pulsed with 10 µM salicylic acid, 25 and 50 µM acetylsalicylic acid. Significant rooting was not observed on direct exposure of microshoots to live RSB. However, high rooting percentages of 70 % and 90 % were observed when microshoots were transferred to WPM amended with 2.5 ml and 0.5 ml of RSB extract obtained at pH 7 respectively. Of all the treatments tested, treatment of 5 to 6 wk old microshoots with 4.9 µM IBA stimulated the best and most consistent rooting efficiency of 70 to 100 %. Histological studies of root formation and leaf growth were also conducted. Root formation from microshoots started within 10 days of transfer to rooting medium. Microshoots grown on WPM amended with 4.9 µM IBA and leaf samples taken from various stages of micropropagation were sectioned and stained using Flemings triple stain. Leaf sections from plants in the greenhouse were found to be fully acclimatized as the anatomy and arrangement of tissues strongly resembled those from mature dogwood trees

'Enhancing the Employability of Students’ Passing from Technical Institutions

India has the world’s second largest education system and provides one of the largest pool of skilled manpower. In the recent years, the problem of under-employment or rather unemployment among technical and professional engineering graduates & diploma pass outs is a cause of serious concern. Substandard Institutes are producing mere graduates & diploma holders instead of technically sound and competent professionals as intended. These pass outs are either under- employed or if employed, they do not fulfill or meet out the expectations of Industries or organizations. There is immediate need to take few corrective measures by the academic coordinators, policy makers and management of the institutes associated in providing technical manpower to the industries system; otherwise India will face an explosion of unemployed technical graduates/diploma holders. The world of academia will have to understand the nerve of Industries/organizations and require producing true professionals instead of mere graduates/diploma holders. The paper principally focuses on the multiple ways and means with suggested strategies for the technical teachers as well as institutions to plan, practice and administer such innovations in to their daily instructions, so as to fulfill the gap to a large exten

A clinical study of patients with central venous catheter associated bloodstream infections in a tertiary care hospital

Background: Central venous access puts the patients at risk of iatrogenic complications and is associated with bloodstream infections. Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus and Methicillin Resistant Staphylococcus aureus (MRSA) are responsible for at least two-thirds of the infections followed by Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Enterococcus spp and Acinetobacter spp. Due to the scarcity of Central Venous Catheter associated Blood Stream Infections (CVC-BSI) data, this study was taken up in our tertiary care hospital. Aims: This study is aimed to study the profile of organisms causing CVC-BSI, assess their antimicrobial susceptibility, the clinical course and outcome.Methods: All subjects whose central venous catheter samples (n=84) were sent for culture and sensitivity during the study period were included in this prospective observational study. The study was done in the Department of Microbiology from July 2019 to December 2019. The catheter tips were streaked onto blood agar plate using Roll plate technique. After biochemical identification of the organisms, antimicrobial susceptibility testing was performed by modified Kirby-Bauer disc diffusion method as per the Clinical Laboratory Standard Institute (CLSI) guidelines. Results: Growth of pathogens was seen in 64.3% (n=54). The common organisms were Coagulase Negative Staphylococcus aureus (CONS) in 27.78% (n=15), Enterococcus spp, Klebsiella pneumoniae in 14.8% each (n=8) and Acinetobacter spp in 11.1% (n=6). Resistance was seen with amoxicillin + clavulanic acid, cefepime, ciprofloxacin and cefoperazone. The organisms were sensitive to levofloxacin, tetracycline and vancomycin.Conclusion: Aseptic precautions taken by the healthcare personnel will bring down the infections and curb the spread of multi-drug resistant hospital acquired infections