1,923 research outputs found
Ponseti method for treatment of idiopathic congenital talipes equinovarus at tertiary care center in India
Background: Different treatment methods were tried with variable success rates but Ponseti method of serial casting and manipulation stood apart due to better understanding of foot biomechanics and became accepted choice of treatment worldwide.Methods: 50 patients were enrolled in the study out of which 40 were available for final follow-up. We studied 40 cases during October 2018 to December 2020 at Government Medical College, Aurangabad. Out of 40 cases 31 were male and 9 were female. 25 were unilateral and 15 were bilateral. All cases were idiopathic. 4 inches Plaster of Paris (POP) bandages were cut into half and such 2 inches POP bandages were used for casting. Tenotomies were performed under controlled environment of Operation Theater with general anaesthesia. Number 12 surgical blade was used. Dennis-Browne splint was used for maintenance of correction.Results: Out of total 55 feet studied, 10 feet (18.18%) required tendo Achilles tenotomy and 45 feet (81.82%) were treated with casting alone. There were 8 cases of relapses (20%). All relapsed cases were treated with repeat casting as per Ponseti protocol and none of them required repeat tenotomy. Complications related to plaster were minimal and there were no incidence of rocker bottom deformity.Conclusions: We conclude that in a low income developing country like India where case load is very high; Ponseti method is effective, inexpensive form of treatment with minimal complications. Need for extensive soft tissue procedures vastly reduced with this method
Role of trimetazidine in carbon tetrachloride induced liver damage in rats
Background: Hepatotoxicity by chemicals and drugs is a common clinical problem. Presently very few drugs are showing effectiveness in prevention and treatment of hepatic damage. So in this study, we evaluated the role of trimetazidine in carbon tetrachloride (CCl4) induced liver damage in rats. Objective of current study is to evaluate effects of prophylactic trimetazidine against carbon tetrachloride induced liver damage in rats.Methods: Liver damage was induced in 30 albino rats by CCl4 (0.5 ml/kg, i.p.) once daily for 7 days. Extent of damage was studied by assessing biochemical parameters (SGOT, SGPT, ALP, proteins and bilirubin). These biochemical observations were supplemented by pentobarbitone Sleeping Time and Histological Examination of liver. The effect of co-administration of trimetazidine (doses 5 and 10 mg/kg p. o.) on the above parameters was investigated. Liv.52® was used as Positive Control. Data was analyzed by one way ANOVA, followed by Dunnett's test.Results: Trimetazidine significantly prevented CCl4 induced elevation of serum SGOT, SGPT, ALP and bilirubin (total and direct), and reduction in protein level. Pentobarbitone sleeping time and histological examination of the liver showed consistent results. The results were comparable to that of Liv.52®.Conclusions: Trimetazidine, when administered prophylactically, shows hepatoprotective effect against CCl4 induced liver damage
A prospective study to evaluate functional results of PHILOS locking plate system in management of proximal humerus fractures in adults
Background: Various management options are available for management of proximal humerus fractures where PHILOS plating is one of them. But data available in literature on its use and efficacy in management of all types of proximal humerus fractures is still dicey. So, we through our study attempted to grow our knowledge regarding its functional results, complication rates, etc. for use in coming future.Methods: 30 patients with proximal humerus fractures classified on the basis of Neer’s classification were included in study who were operated from 2018 to 2020 at our institute. These patients were operated by PHILOS locking plate system with either delto-pectoral or trans-deltoid approach and they are followed up at regular intervals to assess them clinicoradiologicallly and functionally by Neer’s criteria.Results: In our study we found maximum incidence of these fracture between age group of 40-80 years (66.66%) with male to female ratio of 2:1 with 19 patients having left sided and 11 patients having right sided proximal humerus fracture. Complications were found in 11 patients (36.67%). Functional evaluation was carried out using Neer’s criteria at final follow up which came to excellent results in 3, satisfactory in 18, unsatisfactory in 7 and failure in 2 patients. Average time of fracture union was 12.62 weeks.Conclusions: PHILOS locking plate system serves good purpose in management of fractures of proximal humerus but requires trained faculty to do this operation who has detailed knowledge about shoulder anatomy and mechanism of injury to reduce complications associated with this type of modality
Anomalous pinning behavior in an incommensurate two-chain model of friction
Pinning phenomena in an incommensurate two-chain model of friction are
studied numerically. The pinning effect due to the breaking of analyticity
exists in the present model. The pinning behavior is, however, quite different
from that for the breaking of analyticity state of the Frenkel-Kontorova model.
When the elasticity of chains or the strength of interchain interaction is
changed, pinning force and maximum static frictional force show anomalously
complicated behavior accompanied by a successive phase transition and they
vanish completely under certain conditions.Comment: RevTex, 9 pages, 19 figures, to appear in Phys. Rev. B58 No.23(1998
Prompt emission polarimetry of Gamma Ray Bursts with ASTROSAT CZT-Imager
X-ray and Gamma-ray polarization measurements of the prompt emission of
Gamma-ray bursts (GRBs) are believed to be extremely important for testing
various models of GRBs. So far, the available measurements of hard X-ray
polarization of GRB prompt emission have not significantly constrained the GRB
models, particularly because of the difficulty of measuring polarization in
these bands. The CZT Imager (CZTI) onboard {\em AstroSat} is primarily an X-ray
spectroscopic instrument that also works as a wide angle GRB monitor due to the
transparency of its support structure above 100 keV. It also has experimentally
verified polarization measurement capability in the 100 300 keV energy
range and thus provides a unique opportunity to attempt spectro-polarimetric
studies of GRBs. Here we present the polarization data for the brightest 11
GRBs detected by CZTI during its first year of operation. Among these, 5 GRBs
show polarization signatures with 3, and 1 GRB shows
2 detection significance. We place upper limits for the remaining 5
GRBs. We provide details of the various tests performed to validate our
polarization measurements. While it is difficult yet to discriminate between
various emission models with the current sample alone, the large number of
polarization measurements CZTI expects to gather in its minimum lifetime of
five years should help to significantly improve our understanding of the prompt
emission.Comment: Accepted for Publication in ApJ ; a figure has been update
Content validation of a new measure of patient-reported barriers to antiretroviral therapy adherence, the I-Score: results from a Delphi study
Background
Over a third of people living with HIV (PLHIV) have suboptimal adherence to antiretroviral therapy (ART). Measures of barriers to ART adherence often lack comprehensiveness. To help manage ART adherence barriers in HIV care, we are developing a new patient-reported outcome measure (PROM) of these barriers (the I-Score).
Methods
We assessed the content validity of 100 items (distinct barriers) to retain only those most relevant to both PLHIV and HIV health/social service providers. A web-based Delphi was conducted in Canada and France, collecting data from December 2018 to October 2019. Items were evaluated on relevance (the combined rated importance and actionability for HIV care of items among both PLHIV and providers); comprehensibility (rated item clarity); comprehensiveness (examined against our conceptual framework); cross-cultural equivalence (based on comparisons by questionnaire language (English, French) and country of residence). Pearson’s chi-square tests were used for comparisons by language, country, gender, and stakeholder group (PLHIV, providers).
Results
Panelists included 40 PLHIV and 57 providers (66% response rate). Thirty-one items were retained based on consensus thresholds for relevance (minimum: 50% for PLHIV, 60% for providers) and showed good comprehensibility and comprehensiveness, when compared to our conceptual framework (representation of: 6/6 domains, 15/20 subdomains). No significant difference in relevance based on language or country was found among retained items, suggestive of cross-cultural equivalence. Among all 100 items, only 6 significant differences on relevance were observed for gender. For 62 items, the relevance ratings of PLHIV and providers differed significantly, with providers showing greater endorsement of all items but one.
Discussion
The Delphi led to a much-needed item reduction. Remaining items highlight the panel’s multidimensional priorities for the PROM on ART adherence barriers, with few, if any, differences by language, country, and gender. While the analyses may lack generalizability and power, the sample size is considered adequate for a PROM validation study.
Conclusion
Retained items showed good content validity. The different patterns of item endorsement observed underscore the utility of engaging multiple stakeholder groups in PROM development for use in clinical practice. The greater endorsement of items by providers versus patients merits further investigation, including the implications of such differentials for measure development.KE is partially supported by a SPOR Mentorship Chair in Innovative Clinical Trials awarded by the CIHR to BL (Grant No. 383427). BL is supported by a career award, LE 250, from the Quebec Ministry of Health for researchers in Family Medicine. The Delphi benefited from methodological expertise and funding from the Quebec SPOR Support Unit -McGill Methodological Developments Platform (Grant No. M006). The Delphi is a subproject of the PROM development study, the I-Score Study, which is supported, in part, by the CIHR HIV Clinical Trials Network (CTN 283) and by a research Grant from the Investigator Initiated Studies Program of Merck Canada Inc. (Grant No. IISP-53538), neither of which had a hand in the design, conduct, or writing up of this work. The opinions expressed in this study are those of the authors and do not necessarily represent those of Merck Canada Inc or its affiliates or related companies
Atomic Scale Sliding and Rolling of Carbon Nanotubes
A carbon nanotube is an ideal object for understanding the atomic scale
aspects of interface interaction and friction. Using molecular statics and
dynamics methods different types of motion of nanotubes on a graphite surface
are investigated. We found that each nanotube has unique equilibrium
orientations with sharp potential energy minima. This leads to atomic scale
locking of the nanotube.
The effective contact area and the total interaction energy scale with the
square root of the radius. Sliding and rolling of nanotubes have different
characters. The potential energy barriers for sliding nanotubes are higher than
that for perfect rolling. When the nanotube is pushed, we observe a combination
of atomic scale spinning and sliding motion. The result is rolling with the
friction force comparable to sliding.Comment: 4 pages (two column) 6 figures - one ep
Tag retention, wound healing, and subsequent reproductive history of southern right whales following satellite-tagging
This paper presents data from 48 resightings of 16 southern right whales that
were satellite-tagged on the South African coast in September 2001, up to and
including 2012. Tag performance in terms of number of days with locations received
was significantly higher in males than females, and lowest in cows with calves, and
attributed to behavioral differences leading to variable degrees of antenna damage.
Resightings occurred from 4 to 4,054 d after tagging: tags were retained in all
whales seen within 27 mo, but were apparently shed in all but one individual seen
within 36 mo of tagging. The exception was a whale that still had the tag present
11 yr after tagging. Healing at the tag site occurred gradually and within 5 yr of
tagging (and 2 yr after tag shedding). No significant difference in the subsequent
frequency of calving was detected between 12 tagged and 382 untagged females
photographed contemporaneously, and although statistical power was low, a 21% or
greater reduction in calving rate in tagged females would seem incompatible with
the observations. The death of one female 3 yr after tagging was more likely attributable
to a ship strike on an animal debilitated by a prolapsed uterus.U.S. National Marine Fisheries Service, Office of Naval Research and gifts from donors to the Oregon State University Marine Mammal Program.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1748-76922016-04-30hb201
Shear rate threshold for the boundary slip in dense polymer films
The shear rate dependence of the slip length in thin polymer films confined
between atomically flat surfaces is investigated by molecular dynamics
simulations. The polymer melt is described by the bead-spring model of linear
flexible chains. We found that at low shear rates the velocity profiles acquire
a pronounced curvature near the wall and the absolute value of the negative
slip length is approximately equal to thickness of the viscous interfacial
layer. At higher shear rates, the velocity profiles become linear and the slip
length increases rapidly as a function of shear rate. The gradual transition
from no-slip to steady-state slip flow is associated with faster relaxation of
the polymer chains near the wall evaluated from decay of the time
autocorrelation function of the first normal mode. We also show that at high
melt densities the friction coefficient at the interface between the polymer
melt and the solid wall follows power law decay as a function of the slip
velocity. At large slip velocities the friction coefficient is determined by
the product of the surface induced peak in the structure factor, temperature
and the contact density of the first fluid layer near the solid wall.Comment: 37 pages, 16 figure
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