Lie symmetries, Kac-Moody-Virasoro algebras and integrability of certain (2+1)-dimensional nonlinear evolution equations

In this paper we study Lie symmetries, Kac-Moody-Virasoro algebras, similarity reductions and particular solutions of two different recently introduced (2+1)-dimensional nonlinear evolution equations, namely (i) (2+1)-dimensional breaking soliton equation and (ii) (2+1)-dimensional nonlinear Schr\"odinger type equation introduced by Zakharov and studied later by Strachan. Interestingly our studies show that not all integrable higher dimensional systems admit Kac-Moody-Virasoro type sub-algebras. Particularly the two integrable systems mentioned above do not admit Virasoro type subalgebras, eventhough the other integrable higher dimensional systems do admit such algebras which we have also reviewed in the Appendix. Further, we bring out physically interesting solutions for special choices of the symmetry parameters in both the systems

Role of gonococcal surface glycoconjugates, their diversity and their role in bacteria-bacteria interaction and bacteria-host interaction

Bacterial interactions with each other and with host cells play a critical role in the pathogenesis of gonorrhea. Bacterial aggregation was observed to be mediated by the interaction between lipooligosaccharide (LOS) and the opacity-associated protein. In this study, I identified a gene encoding a beta-hexosaminidase (NagZ) in Neisseria gonorrhoeae that modulates gonococcal aggregation and biofilm formation. In comparison to the parental strain, a strain with the nagZ gene deleted produced a biofilm with increased mass. Scanning electron microscopy and confocal laser microscopy were able to visualize differences in the biofilms formed by the two strains. Biofilms formed by a strain deficient in nagZ were disrupted by addition of exogenously added purified NagZ. This is the first study to demonstrate that an enzyme thought to be restricted to peptidoglycan recycling is able to moonlight as biofilm modulator. NagZ could play an important role in promoting bacterial escape from a biofilm, along with previously characterized agents such as Nuc thermonuclease. Using strains defective in surface protein glycosylation, I demonstrate that the increase in biofilm formation seen in nagZ mutant is dependent on PglC-mediated surface protein glycosylation. This is the first study demonstrating the role played by surface glycoconjugates in gonococcal biofilm formation. I used bioinformatic analysis to study the diversity of the other major glycoconjugate on gonococcal surface, LOS. I identified significant differences in the LOS core structure between commensals and pathogens within the Neisseriaceae. I generated preliminary data suggesting that N. gonorrhoeae activate inflammasomes in epithelial cells, resulting in production of IL-18. While activation of inflammasomes does not affect production of other cytokines such as IL-8, IL-8 levels were reduced by using MyD88-inhibitors. Gonococcal-induced inflammasome activation in epithelial cells and production of inflammasome-dependent cytokines were further confirmed in human cervix explants

Comparison of two targets of serum bilirubin concentration for phototherapy discontinuation in neonatal jaundice

AIM OF THE STUDY: To compare the occurrence of significant rebound hyperbilirubinemia between two groups of neonates with jaundice, when phototherapy was stopped at serum bilirubin 1-2.9 mg/dl and ≥ 3mg/dl below American Academy of Paediatrics (AAP) treatment threshold. METHODOLOGY: An Open labelled randomised controlled trial was conducted in a teaching hospital. Neonates with ≥ 35 weeks gestation, birth weight > 1800 grams with jaundice requiring phototherapy as per AAP guidelines, in first 7 days of life were included. Neonates planned for exchange transfusion at admission were excluded. Computer generated random numbers were kept in serially numbered opaque sealed envelope. After recruitment, the envelope was opened and babies were assigned into groups accordingly. Phototherapy was stopped at serum bilirubin 1- 2.9mg/dl in group A and ≥3mg/dl in group B. After stopping phototherapy serum bilirubin was measured at about 6 and 24 hours. RESULTS: We recruited 99 babies in each group and after excluding the lost to follow up, 83 babies in group A and 77 in group B who completed the study were taken for analysis. 2 babies in each group required re-initiation of phototherapy, but not statistically significant (p = 0.661). The mean duration of phototherapy was significantly less in group A (14.9 hours) when compared to group B (19.5 hours) (p = 0.000). The duration of hospitalization was not significantly different between groups (p = 0.695). CONCLUSION: We found that the occurrence of significant rebound hyperbilirubinemia was not significantly different between two groups, when phototherapy was stopped at 1-2.9mg/dl and ≥ 3mg/dl below AAP treatment threshold

Hematopoietic cell transplantation and gene therapy for Diamond-Blackfan anemia: state of the art and science

Diamond-Blackfan anemia (DBA) is one of the most common inherited causes of bone marrow failure in children. DBA typically presents with isolated erythroid hypoplasia and anemia in infants. Congenital anomalies are seen in 50% of the patients. Over time, many patients experience panhematopoietic defects resulting in immunodeficiency and multilineage hematopoietic cytopenias. Additionally, DBA is associated with increased risk of myelodysplastic syndrome, acute myeloid leukemia and solid organ cancers. As a prototypical ribosomopathy, DBA is caused by heterozygous loss-of-function mutations or deletions in over 20 ribosomal protein genes, with RPS19 being involved in 25% of patients. Corticosteroids are the only effective initial pharmacotherapy offered to transfusion-dependent patients aged 1 year or older. However, despite good initial response, only ~20-30% remain steroid-responsive while the majority of the remaining patients will require life-long red blood cell transfusions. Despite continuous chelation, iron overload and related toxicities pose a significant morbidity problem. Allogeneic hematopoietic cell transplantation (HCT) performed to completely replace the dysfunctional hematopoietic stem and progenitor cells is a curative option associated with potentially uncontrollable risks. Advances in HLA-typing, conditioning regimens, infection management, and graft-versus-host-disease prophylaxis have led to improved transplant outcomes in DBA patients, though survival is suboptimal for adolescents and adults with long transfusion-history and patients lacking well-matched donors. Additionally, many patients lack a suitable donor. To address this gap and to mitigate the risk of graft-versus-host disease, several groups are working towards developing autologous genetic therapies to provide another curative option for DBA patients across the whole age spectrum. In this review, we summarize the results of HCT studies and review advances and potential future directions in hematopoietic stem cell-based therapies for DBA

LOAN REPAYMENT PERFORMANCE OF MICRO SMALL ENTERPRISES

Micro and small business is an entity that is privately owned and operated, with a small number of employees and relatively low volume of sales. The term MSE incorporates firms in both the formal and informal sectors. The main purpose of this study is to critically evaluate the loan repayment performance of privately owned small-scale enterprises financed by Omo Micro Finance Institution and to investigate the major determinants behind their loan recovery record and to examine the impact of the identified factors on the loan repayment performance of Micro and Small Enterprises credit scheme. In this study both descriptive and causal type of the Research design is used Population comprised of Borrowers of 278 Micro and Small Enterprises of Omo micro finance in Wolaita Sodo town. Stratified Random sampling is used. the first stage, by stratified sampling 164 MSEs were selected based on the pre-determined scientific method from five different sectors of enterprise organization in the sector from the town. For the study Primary as well as secondary data had been used. Structured questionnaire had been used to collect first hand data from small and micro enterprises through field survey. The data collected from the field were analyzed using the descriptive statistical tools like percentages, mean and standard deviation. In addition, the regression model (multiple regression models) had been used to analyze the loan repayment performance of the micro and small enterprises. The variables are Beneficiary size of the enterprises, business related experience, loan size, loan supervision, loan initiation and suitability of repayment situation. The evidences of both descriptive analysis and multiple regression show that business related experience is found to be one of the major determinants adversely affecting the loan repayment performance.The informal sector will benefit from the study findings by understanding the reasons why financial institutions are not able to meet some of their financial demands whilst having pending loan repayment cases from their sector. The study is expected to stimulate more research on factors that influence loan repayment in other sectors of the economy and develop ways in which loan repayment rates can be improve

Progression in the Morphology of Fuel Cell Membranes upon Conjoint Chemical and Mechanical Degradation

Ionomer membranes used to separate the electrodes in polymer electrolyte fuel cells are known to degrade both chemically and mechanically during regular fuel cell operation and may ultimately result in lifetime-limiting failure. The objective of the present work is to understand the effects of combined chemical and mechanical stresses on the mesoscale morphology of the membrane and its role in the overall degradation process. The mesoscale effects of sulfonic acid group loss and fluoride release on the phase segregated morphology of the membrane are analyzed using contrast-enhanced transmission electron microscopy and energy dispersive X-ray spectroscopy. The end-of-life ionic domain size of the ionomer is shown to be substantially enlarged compared to the pristine membrane state. Elemental mapping overlayed with the binary ionic and non-ionic morphology reveals mesoscopic void regions in the degraded material that are depleted of ionomer fluorine and carbon and considered susceptible to micro-crack initiation. A larger, severely degraded void region is also identified which contains evidence of hygrothermal stress induced localized ionomer crazing as a potential nucleation site for macroscopic fracture development. The synergetic effects of chemical and mechanical degradation on the progressive changes in the observed mesoscale morphology are discussed

A note on the Painleve analysis of a (2+1) dimensional Camassa-Holm equation

We investigate the Painleve analysis for a (2+1) dimensional Camassa-Holm equation. Our results show that it admits only weak Painleve expansions. This then confirms the limitations of the Painleve test as a test for complete integrability when applied to non-semilinear partial differential equations.Comment: Chaos, Solitons and Fractals (Accepted for publication