10,990 research outputs found
Expectation of forward-backward rapidity correlations in collisions at the LHC energies
Forward-backward correlation strength () as a function of pesudorapidity
intervals for experimental data from non-singly diffractive
collisions are compared to PYTHIA and PHOJET model calculations. The
correlations are discussed as a function of rapidity window ()
symmetric about the central rapidity as well as rapidity window separated by a
gap () between forward and backward regions. While the correlations
are observed to be independent of , it is found to decrease with
increase in . This reflects the role of short range correlations
and justifies the use of to obtain the accurate information about
the physics of interest, the long range correlations. The experimental
value shows a linear dependence on with the maximum value of
unity being reached at = 16 TeV, beyond the top LHC energy. However
calculations from the PYTHIA and PHOJET models indicate a deviation from linear
dependence on and saturation in the values being reached
beyond = 1.8 TeV. Such a saturation in correlation values could have
interesting physical interpretations related to clan structures in particle
production. Strong forward-backward correlations are associated with cluster
production in the collisions. The average number of charged particles to which
the clusters fragments, called the cluster size, are found to also increase
linearly with for both data and the models studied. The rate of
increase in cluster size vs. from models studied are larger
compared to those from the data and higher for PHOJET compared to PYTHIA. Our
study indicates that the forward-backward measurements will provide a clear
distinguishing observable for the models studied at LHC energies.Comment: 15 pages, 14 Figures, accepted for publication in International
Journal of Modern Physics
Evaluation of triglyceride: HDL-C ratio and Non-HDL-C as harbingers of increased cardiovascular risk in metabolic syndrome
Background: Metabolic syndrome is an aggregate of conditions that together increases the risk of developing cardiovascular disease and type 2 diabetes mellitus. Dyslipidemia consisting of elevated triglyceride, decreased HDL, and altered triglyceride to high density lipoprotein- Cholesterol (TG/HDL-C) ratio is useful in predicting cardiometabolic risk and insulin resistance. The present study aimed to compile further evidence for clinical utility of TG/HDL-C ratio and Non HDL-C as simple, cost effective tools for early identification of cardiovascular disease risk in metabolic syndrome.Methods: This study was carried out with hundred subjects. Fifty of these subjects were diagnosed with metabolic syndrome according to National Cholesterol Education Program Adult Treatment Panel III; while other fifty were age and gender matched healthy control subjects.Results: The impact of cardiometabolic markers on metabolic syndrome was assessed separately in men and women by applying Mann Whitney ‘U’ test. Study showed highly significant increase in TG, HDL, TC/TG and TG/HDL-C ratio in women compared to men with p<0.01. The odds ratio of TG/HDL for women showed the highest ratio of 6, 95% CI (1.5225 to 23.6401) p=0.006 compared to men 4.9583, 95% CI (1.0088-24.3711), p=0.004.Conclusions: This study demonstrated that TG/HDL-C ratio and Non HDL-C are strongly associated with metabolic syndrome in urban population. In comparison, TG/HDL-C is a better predictor of metabolic syndrome than non-HDL-C
Audit of caesarean deliveries in a tertiary care hospital of northern Andhra Pradesh using modified Robson criteria
Background: Today, there is an increased trend in the incidence of caesarean section (CS) rate worldwide particularly in India, even with the lack of evidence supporting considerable maternal and perinatal benefits with higher CS rates. The main objective of our study was to find the incidence of CS rate, auditing the data on the basis of modified Robson criteria, factors responsible for the most common group, to know the changing trends of CS and finally put forth the strategies to reduce CS rate.Methods: This is a retrospective study of 472 CS cases carried out in a tertiary care hospital during the year 2016. All the cases were grouped according to the modified Robson criteria and the data was analyzed. The data were grouped into 3 different slots of 4 months each (FF = first four months; MF = middle four months and LF = last four months of the year 2016).Results: A significant increasing trend was observed in the groups of 2B and 5C where as a significant decreasing trend was noticed in 6C and 7C. The most common indications for caesarean delivery were cephalo-pelvic disproportion (CPD) (28%) and fetal distress (22%) in group 1 whereas in group 2A CPD, fetal distress and failed induction were found to be 12%, 24% and 30% respectively.Conclusions: The change in trend has been noticed in the last few months particularly in 2B and 5C groups suggesting that there is a change in the attitude of obstetricians in conducting caesarean deliveries before the onset of labour rather than performing CS after the onset of labour. Targeting 2B along with 5C would help our efforts in reducing the CS rate
The crystal structure of benzyloxycarbonyl-(α-aminoisobutyryl)-L-alanyl methyl ester
Crystals of the title compound, C20,H29,N3,O6, are monoclinic, space group P2, with a = 8-839 (3), b = f10.818 (3), c = 11.414 (2) A, β = 95.69 (2)° Z = 2; final R = 0.053. The molecular conformation is defined by the following angles (φ, ψ): Aib-1 58- 1, 36.8; Aib-2 68.3, 18.6; Ala-3 (φ) -136.2°. The molecule adopts a type 111 β -turn conformation stabilized by an intramolecular hydrogen bond between the CO of the benzyloxycarbonyl group and the NH of the alanyl residue. The hydrogen-bond parameters are N···O 2-904 Å and ∠NH···O 156.9°
Behaviour of Magnetic Tubes in Neutron Star's Interior
It is found from Maxwell's equations that the magnetic field lines are good
analogues of relativistic strings. It is shown that the super-conducting
current in the neutron star's interior causes local rotation of magnetic flux
tubes carrying quantized flux.Comment: 6 pages, no figure
Network Management System for (FUTON-like) Radio-over- Fiber Infrastructure
EU-Project FUTON Radio-over-Fiber (RoF) infrastructure proposes high transmission rates at small antenna costs, implying competitive CAPEX for next generation networks. But to be cost-efficient, it needs to employ new network architectures and intelligent technology solutions for decreasing network operational costs. The RoF Network Manager manages the network equipment on the optical front haul between the Central Unit (CU) and all Remote Antenna Units (RAU)s connected by it, as well as the communication links, while enabling end-to-end service problem resolution and service quality management by the FUTON Middleware. Although a significant amount of prior research work can be found in the literature related to RoF, there is still significant lack of technologies concerning RoF networks management. RoF Manager and its sub-systems target to fill such gap, proposing a novel concept in the form of Channel Forwarding Table (CFT). RoF Manager follows an autonomous and generic network management framework, designed to be scalable in terms of adding new network elements (NEs). It targets multitechnology, multi-service and multi-vendor NEs in the network using Simple Network Management Protocol (SNMP). It can also provide alternative paths in case of failure. This work puts forward a new paradigm towards RoF management solution managing network performance, network faults, network security and configurations for convergent networks
Ferromagnetic Ordering in CeIr2B2: Transport, magnetization, specific heat and NMR studies
We present a complete characterization of ferromagnetic system CeIr2B2 using
powder x-ray diffraction XRD, magnetic susceptibility chi(T), isothermal
magnetization M(H), specific heat C(T), electrical resistivity rho(T,H), and
thermoelectric power S(T) measurements. Furthermore 11B NMR study was performed
to probe the magnetism on a microscopic scale. The chi(T), C(T) and rho(T) data
confirm bulk ferromagnetic ordering with Tc = 5.1 K. Ce ions in CeIr2B2 are in
stable trivalent state. Our low-temperature C(T) data measured down to 0.4 K
yield Sommerfeld coefficient gamma = 73(4) mJ/molK2 which is much smaller than
the previously reported value of gamma = 180 mJ/molK2 deduced from the specific
heat measurement down to 2.5 K. For LaIr2B2 gamma = 6(1) mJ/molK2 which implies
the density of states at the Fermi level D(EF) = 2.54 states/(eV f.u.) for both
spin directions. The renormalization factor for quasi-particle density of
states and hence for quasi-particle mass due to 4f correlations in CeIr2B2 is
12. The Kondo temperature TK ~ 4 K is estimated from the jump in specific heat
of CeIr2B2 at Tc. Both C(T) and rho(T) data exhibit gapped-magnon behavior in
magnetically ordered state with an energy gap Eg ~ 3.5 K. The rho data as a
function of magnetic field H indicate a large negative magnetoresistance (MR)
which is highest for T = 5 K.While at 5 K the negative MR keeps on increasing
up to 10 T, at 2 K an upturn is observed near H = 3.5 T. On the other hand, the
thermoelectric power data have small absolute values (S ~ 7 {\mu}V/K)
indicating a weak Kondo interaction. A shoulder in S(T) at about 30 K followed
by a minimum at ~ 10 K is attributed to crystal electric field (CEF) effects
and the onset of magnetic ordering. 11B NMR line broadening provides strong
evidence of ferromagnetic correlations below 40 K.Comment: 10 pages, 11 figure
Model simulation of tide-induced currents in Gauthami-Godavari estuary
Predictive spatial distribution of flow field has been simulated from the time series data on currents and tides during dry season (11-19, February, 2009) in the Gauthami-Godavari Estuary utilizing TIDAL model. A 2D-Tidal Estuarine model has been considered (instead of 3D model) due to well-mixed type system and its circulation is dominated by tides during the observational period. The model forcing functions consist of wind and tidal elevations along the open boundaries and no fresh water inflow from the main stream and no land flood in river system. The bathymetry data of the river basin has been collected and supplemented to the model as one of the rigid boundary conditions to evaluate integration. The bottom roughness length (K) was adjusted to achieve model calibration and verification in model simulations of flow field. The model simulation results are in qualitative agreement with the observational data with calibrated bottom roughness length which is about 0.085 m. Model results reveal that the majority of flow was found to be along the channel axis (i.e. high iso-bath contour). During flood time, flow is south-west direction and it is changed to northeast direction during ebb period which is indicating that the model results resemble flow in the real eastern system
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