308 research outputs found
Dependence of Self-Assembled Peptide Hydrogel Network Structure on Local Fibril Nanostructure
Physically cross-linked, fibrillar hydrogel networks are formed by the self-assembly of β-hairpin peptide molecules with varying degrees of strand asymmetry. The peptide registry in the self-assembled state can be used as a design element to generate fibrils with twisting, nontwisting, or laminated morphology. The mass density of the networks varies significantly, and can be directly related to the local fibrillar morphology as evidenced by small angle neutron scattering (SANS) and in situ substantiation using cryogenic transmission electron microscopy (cryo-TEM) under identical concentrations and conditions. Similarly, the density of the network is dependent on changes in the peptide concentration. Bulk rheological properties of the hydrogels can be correlated to the fibrillar nanostructure, with the stiffer, laminated fibrils forming networks with a higher G′ as compared to the flexible, singular fibrillar networks
Correlation and coordination risk
We study the potential role of correlated refinancing abilities among di.erent countries for the disruption of government bond markets in a currency union. Following Morris and Shin (2004) we use a global games framework and model the simultaneous investment decision into two assets, which are subject to correlated fundamental states, as a coordination problem with correlated imperfect information. Based on this model we evaluate the role of information about one country for the coordination of creditors of another country. We find, however, that the contagious e.ects on the price of debt precipitated through correlation are modest. Hence, assuming that investors behave as modeled in the global game, we conclude that correlated fundamentals that precipitate informational spillovers appear to be unlikely to play a major role for e.g. the disruption of some Eurozone government bond markets in the aftermath of the recent financial and economic crisis
Fishery and biology of Penaeid prawns at Harnaii, Mahatashtra
Penaeid prawn fishery at Harnaii in Ratnagiri District of Maharashtra was investigated during fishing seasons of 2002-03 and 2003-04 from mechanized (MLD) and hand operated trawlers (HT). During the two years, MLD contributed 86% and HT 14% to the average annual penaeid prawn catch of 2,242 t. The catch showed two peaks, a major during October-December and a minor during April-May in both the gears but abundance of the individual species differed. P. stylifera, Metapenaeopsis affinis, Solenocera crassicornis, Metapenaeopsis brevicornis, P. merguiensis and Metapenaeopsis dobsoni mainly constituted the fishery and their species composition, seasonal abundance, annual size distribution and monthly mean size were investigated. Biological studies on food, size at maturity, spawning period, sex-ratio and juvenile abundance were carried out to explain temporal abundance of the species in the fishery. Among the species P. stylifera, M. affinis and S. crassicornis exhibited distinct seasonality with two spawning peaks, one in pre-monsoon and the other in post monsoon period to produce two discrete broods while P. merguiensis despite two spawning peaks exhibited a single dominant brood. M. brevicornis showed monsoon and post-monsoon spawning while M. dobsoni showed only post-monsoon spawning. Migrations between nearshore and offshore waters resulted in mixing of the broods and they remained inseparable in the catch
Natural diet of penaeid prawns in the coastal waters of Mumbai
Foregut contents of eight commercially important species of penaied prawns namely Penaeus merguiensis, Metapenaeus affinis, M. monoceros, M. brevicornis, Parapenaeopsis stylifera, P. hardwickii, P. sculptilis and Solenocera crassicornis were investigated from inshore, nearshore and offshore fishing grounds of Mumbai. Feeding intensity and index of preponderance (IP) of the dietary items were compared statistically for the species, sexes, fishing areas and maturity condition of females. All the species except M. monoceros and P. sculptilis showed that females were better fed than males. The feeding intensity in the three depth-zones was different for M. affinis, M. brevicornis, M. monoceros, P. hardwickii and S. crassicornis, and uniform for P. merguiensis, P. stylifera and P. sculptilis. Acetes spp., prawn remains, polychaetes, benthic crustaceans, foraminifers and fish remains were the important food items of the prawns. Dietary comparison between the two sexes of the species did not show any difference, but mature females of M. monoceros and P. sculptilis had different diets. Comparison of food items for all the species together showed significant difference between the three areas. Crustacean diet was the favorite in the inshore and nearshore, and polychaetes in the offshore waters. All the species except P. hardwickii showed difference in their dietary composition in the three depth-zones. It is concluded that these coexisting species are primarily carnivorous and exhibit diverse food preferences in different depth-zones by browsing on interstitial organisms, chasing epipelagic prey, raptorial predation, scavenging on dead organisms or adopting different temporal abundance to avoid inter-specific competition for food
Assessment of Anaerobic Power and Balance among Elite Indian Under-19 Football Players
Objective: To assess anaerobic power and balance among elite indian under-19 football players. Method:22 Elite Indian
under-19 players Football players were tested for Anaerobic power and Balance on Monark Cycle Ergometry and Neurocom Balance Master respectively.
Result: Anaerobic Peak Power (W) for professional Indian under-19 football players was 498.70, while the mean for
the Anaerobic Capacity (W/Kg) was 7.75. On Balance assessment, players had maximum sway velocity on foam surface with eyes closed with a mean of 0.76 (deg/sec) followed by eyes open on a foam surface with a mean of 0.54 (deg/sec). Reaction Time of players was found to be affected most in the forward component with a mean of 0.98(deg/sec) followed by Right direction and Left back direction component with mean of 0.69 and 0.67 respectively. The players showed lack of directional control maximum in the Right component with a mean of 87.25 (deg/sec) followed by Forward and Left components with mean of 86.89 and 81.10 respectively.
Conclusion: Elite Indian under-19 players Football players were found to have low Anaerobic power and capacity with their reaction time and directional control affected on the dominant leg side
Antibodies to group A streptococcal virulence factors, SIC and DRS, increase predilection to GAS pyoderma
Background:
Streptococcus pyogenes (group A streptococcus; GAS) is an etiological agent for pharyngitis, pyoderma, and invasive infections in humans. Pharyngitis and pyoderma may lead to serious immune sequelae such as rheumatic heart disease and post-streptococcal glomerulonephritis (PSGN). Streptococcal Inhibitor of Complement (SIC) and its orthologue, distantly related to SIC (DRS), are virulence factors expressed by only four of more than 100 M types of GAS. These four types (M1, M57, M12 and M55) are among the M types, which are associated with PSGN. In several populations PSGN has been shown to be a risk factor for chronic kidney disease (CKD) and end-stage renal disease (ESRD). Previous studies showed SIC or DRS antibody-prevalence was associated with PSGN, and seroprevalence of SIC antibodies is significantly high among CKD and ESRD patients in Mumbai.
Methods:
Streptococcal isolates recovered from GAS pyoderma cases were typed. Seropositivity for SIC and DRS antibodies in subjects with pyoderma, PSGN pediatric cases, age matched healthy controls and non-GAS pyoderma cases were determined.
Results:
We confirm in this study an association between seroprevalence to SIC and DRS antibodies, and PSGN in Mumbai population despite low point prevalence of M1, M12, M55 and M57. In addition we extended the study to GAS-pyoderma and non-GAS pyoderma cases. To our surprise, we found a positive association between the seroprevalence to SIC and DRS antibodies, and GAS-pyoderma owing to infection with diverse M types. The mechanism of increased predisposition to pyoderma owing to infection by diverse GAS among SIC or DRS antibody-positive population is not clear. Nonetheless, our findings could be explained by a phenomenon akin to antibody-dependent enhancement (ADE).
Conclusions:
This is the first report showing a small number of GAS M types conferring predisposition to pyoderma by diverse types. Implications of this ADE-like phenomenon are discussed in the light of evolutionary advantage to GAS, vaccine design and control of renal diseases.Full Tex
Linking micellar structures to hydrogelation for salt-triggered dipeptide gelators
Some functionalised dipeptides can form hydrogels when salts are added to solutions at high pH. We have used surface tension, conductivity, rheology, optical, confocal and scanning electron microscopy, 1H NMR and UV-Vis spectroscopy measurements to characterise fully the phase behaviour of solutions of one specific gelator, 2NapFF, at 25 °C at pH 10.5. We show that this specific naphthalene–dipeptide undergoes structural transformations as the concentration is increased, initially forming spherical micelles, then worm-like micelles, followed by association of these worm-like micelles. On addition of a calcium salt, gels are generally formed as long as worm-like micelles are initially present in solution, although there are structural re-organisations that occur at lower concentrations, allowing gelation at lower than expected concentration. Using IR and SANS, we show the differences between the structures present in the solution and hydrogel phases
Micro, small and medium-sized enterprise policies: A cohered emergent and institutional theory perspective.
This thesis examined the disconnect between policy formulation and implementation for Micro, Small, and Medium Enterprises (MSMEs) in Nigeria, with a focus on how a collaborative, co-created approach can enhance policy effectiveness. Drawing on Institutional Theory and the Cohered Emergent Framework, the study explored the perspectives of key stakeholders, including MSME owners, managers, and policymakers. There were 30 Semi-structured interviews conducted to gather primary data from MSMEs in North-Central Nigeria. Thematic analysis was employed to identify recurring patterns and themes from the qualitative data which provide a structured approach to interpreting participants' perspectives. retrieval of data, ensuring a systematic analysis of key themes and insights.
The key findings revealed significant misalignment between policy objectives and the actual needs of MSMEs, often exacerbated by insufficient stakeholder involvement in the policy-making process. The results highlight that while policies exist to support MSMEs, their implementation often fails to address the challenges faced by businesses in the sector, including access to finance, regulatory hurdles, and inadequate infrastructure. The study concludes that a more inclusive, stakeholder-driven approach to policy formulation that considers the unique socio-economic and cultural contexts of Nigerian MSMEs. The research makes a significant contribution by developing a Cohered MSME Policy Framework that can support the co-creation of policies in Nigeria. It also offers recommendations for policymakers to enhance MSME performance, highlighting the importance of strengthened collaboration and feedback mechanisms in promoting the sector’s sustainable development
- …
