1,074 research outputs found
Acetabular fractures –Clinical outcomes of surgical management
Introduction : The fractures of acetabulum concern 2% of fractures and it is difficult to be diagnosed and treated.Improvements in automobile safety, pre-hospital care, resuscitation and transport as well as standardized protocols for treatment have all contributed to improved survival after these devastating injuries
Materials and methods : The operative treatment of acetabular fractures was performed in Vinayaka Mission Kirupananda Variyar Medical College and Hospital from July 2010 to July 2019. 32 patients had an open reduction and internal fixation of an acetabular fracture. 25 were males and 7 were females, with an age ranging from 28 to 62 years (average: 36.7 years). The mechanism of injury was a motor vehicle accident in most cases (85%). The fractures were classified with Judet-Letournel classification. The patients were operated upon within 1-8 days (average: 4 days). The Kocher-Langenbeck surgical approach was used in 22 cases and ilioinguinal approach in 10 patients. Osteosynthesis was achieved with either lag screws alone or with a combination of lag screws and a buttress plate. Follow-up ranged from 6 months - 9 years (average: 3.8 years).
Results: Clinical evaluation according to the D' Aubigne-Postel scoring system gave 23 excellent (71.9%), 6 good (18.8%), 2 fair (6.3%) and 1 poor (3.1%) results. Early postoperative complications included 1 case of unexplained bleeding through drain tube for 8 days and superficial wound infection in another 3 patients.
Conclusion : Operative treatment of acetabular fractures although demanding, bears very good results
1-[2-(2,4-Dinitrobenzylideneamino)phenyl]-3-phenylthiourea
In the title compound, C20H15N5O4S, the central benzene ring makes dihedral angles of 59.5 (1) and 51.7 (1)°, respectively, with the terminal phenyl and benzene rings. The molecular structure exhibits weak intramolecular N—H⋯N and C—H⋯S interactions. In the crystal structure, molecules are linked by weak intermolecular N—H⋯S and C—H⋯O interactions, forming a chain along [11]
Weighing neutrinos using high redshift galaxy luminosity functions
Laboratory experiments measuring neutrino oscillations, indicate small mass
differences between different mass eigenstates of neutrinos. The absolute mass
scale is however not determined, with at present the strongest upper limits
coming from astronomical observations rather than terrestrial experiments. The
presence of massive neutrinos suppresses the growth of perturbations below a
characteristic mass scale, thereby leading to a decreased abundance of
collapsed dark matter halos. Here we show that this effect can significantly
alter the predicted luminosity function (LF) of high redshift galaxies. In
particular we demonstrate that a stringent constraint on the neutrino mass can
be obtained using the well measured galaxy LF and our semi-analytic structure
formation models. Combining the constraints from the Wilkinson Microwave
Anisotropy Probe 7 year (WMAP7) data with the LF data at z = 4, we get a limit
on the sum of the masses of 3 degenerate neutrinos \Sigma m_\nu < 0.52 eV at
the 95 % CL. The additional constraints using the prior on Hubble constant
strengthens this limit to \Sigma m_\nu < 0.29 eV at the 95 % CL. This neutrino
mass limit is a factor of order 4 improvement compared to the constraint based
on the WMAP7 data alone, and as stringent as known limits based on other
astronomical observations. As different astronomical measurements may suffer
from different set of biases, the method presented here provides a
complementary probe of \Sigma m_\nu . We suggest that repeating this exercise
on well measured luminosity functions over different redshift ranges can
provide independent and tighter constraints on \Sigma m_\nu .Comment: 14 pages, 7 figures, submitted to PR
Constrained semi-analytical models of Galactic outflows
We present semi-analytic models of galactic outflows, constrained by
available observations on high redshift star formation and reionization.
Galactic outflows are modeled in a manner akin to models of stellar wind blown
bubbles. Large scale outflows can generically escape from low mass halos
(M<10^9 M_sun) for a wide range of model parameters but not from high mass
halos (M> 10^{11} M_sun). The gas phase metallicity of the outflow and within
the galaxy are computed. Ionization states of different metal species are
calculated and used to examine the detectability of metal lines from the
outflows. The global influence of galactic outflows is also investigated.
Models with only atomic cooled halos significantly fill the IGM at z~3 with
metals (with -2.5>[Z/Z_sun]>-3.7), the actual extent depending on the
efficiency of winds, the IMF, the fractional mass that goes through star
formation and the reionization history of the universe. In these models, a
large fraction of outflows at z~3 are supersonic, hot (T> 10^5 K) and have low
density, making metal lines difficult to detect. They may also result in
significant perturbations in the IGM gas on scales probed by the Lyman-alpha
forest. On the contrary, models including molecular cooled halos with a normal
mode of star formation can potentially volume fill the universe at z> 8 without
drastic dynamic effects on the IGM, thereby setting up a possible metallicity
floor (-4.0<[Z/Z_sun]<-3.6). Interestingly, molecular cooled halos with a
``top-heavy'' mode of star formation are not very successful in establishing
the metallicity floor because of the additional radiative feedback, that they
induce. (Abridged)Comment: 27 pages, 31 figures, 2 tables, pdflatex. Accepted for publication in
MNRA
Role of Vitamin A and Vitamin D in management of polycystic ovary syndrome
Polycystic ovarian syndrome (PCOS), a very common cause of infertility in reproductive age groups, has increased exponentially in the past few years registering 9% of cases annually worldwide. It is one of the most common syndromes which manifests hormone secretion and its activity. Insulin resistance, obesity, Vitamin and mineral deficiency, etc., are commonly associated with PCOS. Vitamin A is a lipid-soluble vitamin that is useful in antioxidant activity and steroid synthesis is known to prevent the occurrence of PCOS. Vitamin D, a steroid hormone originating from cholesterol is commonly known as “the sunshine vitamin,” is also one of the observed vitamin deficiencies in PCOS women. Supplementation of Vitamins in the diet is essential in the management of PCOS women. This review attempts to brief the role of Vitamin A and Vitamin D as an important agent to overcome the challenges of PCOS by reviewing the investigations of various authors about the potential role of supplementation of Vitamin A and Vitamin D in various model organisms and Randomised Clinical Trials (RCT’s)
Constraints on Variant Axion Models
A particular class of variant axion models with two higgs doublets and a
singlet is studied. In these models the axion couples either to the -quark
or -quark or both, but not to , , , or . When the axion couples
to only one quark the models possess the desirable feature of having no domain
wall problem, which makes them viable candidates for a cosmological axion
string scenario. We calculate the axion couplings to leptons, photons and
nucleons, and the astrophysical constraints on the axion decay constant
are investigated and compared to the DFSZ axion model. We find that the most
restrictive lower bound on , that from SN1987a, is lowered by up to a
factor of about 30, depending on the model and also the ratio of the vacuum
expectation values of the higgs doublets. For scenarios with axionic strings,
the allowed window for in the quark model can be more than two orders
of magnitude. For inflationary scenarios, the cosmological upper bound on
, where is the QCD anomaly factor, is unaffected: however, the
variant models have either 3 or 6 times smaller than the DFSZ model.Comment: 21pp RevTeX, 1 eps fig, uses graphics style, typo corrected, and
corrected file sent this time. To appear in Physical Review
On the resilience of helical magnetic fields to turbulent diffusion and the astrophysical implications
The extent to which large scale magnetic fields are susceptible to turbulent
diffusion is important for interpreting the need for in situ large scale
dynamos in astrophysics and for observationally inferring field strengths
compared to kinetic energy. By solving coupled equations for magnetic energy
and magnetic helicity in a system initiated with isotropic turbulence and an
arbitrarily helical large scale field, we quantify the decay rate of the latter
for a bounded or periodic system. The energy associated with the non-helical
magnetic field rapidly decays by turbulent diffusion, but the decay rate of the
helical component depends on whether the ratio of its magnetic energy to the
turbulent kinetic energy exceeds a critical value given by M_{1,c}
=(k_1/k_2)^2, where k_1 and k_2 are the wave numbers of the large and forcing
scales. Turbulently diffusing helical fields to small scales while conserving
magnetic helicity requires a rapid increase in total magnetic energy. As such,
only when the helical fields are sub-critical can they so diffuse. When
super-critical, the large scale helical field decays slowly, at a rate
determined by microphysical dissipation even when macroscopic turbulence is
present. Amplification of small scale magnetic helicity abates the turbulent
diffusion. Two implications are that: (1) Standard arguments supporting the
need for in situ large scale dynamos based on the otherwise rapid turbulent
diffusion of large scale fields require re-thinking since only the non-helical
field is so diffused in a closed system. Boundary terms could however provide
potential pathways for rapid change of the large scale helical field. (2) Since
M_{1,c} <<1 for k_1 << k_2, the presence of long-lived ordered large scale
helical fields, as in extragalactic jets, does not guarantee that the magnetic
field dominates the kinetic energy.Comment: published in MNRAS (in this replacement, the missing .bbl file has
been added
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