Measurement of quarkonium production at forward rapidity in [Formula: see text] collisions at [Formula: see text]TeV

The inclusive production cross sections at forward rapidity of [Formula: see text], [Formula: see text], [Formula: see text](1S) and [Formula: see text](2S) are measured in [Formula: see text] collisions at [Formula: see text] with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.35 pb[Formula: see text]. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the [Formula: see text] invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum [Formula: see text] and rapidity [Formula: see text], over the ranges [Formula: see text] GeV/c for [Formula: see text], [Formula: see text] GeV/c for all other resonances and for [Formula: see text]. The measured cross sections integrated over [Formula: see text] and [Formula: see text], and assuming unpolarized quarkonia, are: [Formula: see text] [Formula: see text]b, [Formula: see text] [Formula: see text]b, [Formula: see text] nb and [Formula: see text] nb, where the first uncertainty is statistical and the second one is systematic. The results are compared to measurements performed by other LHC experiments and to theoretical models.

Dexamethasone and haemorrhage risk in paediatric tonsillectomy: a systematic review and meta-analysis

Summary In children undergoing tonsillectomy, dexamethasone is recommended to reduce the risk of postoperative nausea and vomiting while non-steroidal anti-inflammatory drugs (NSAIDs) are used for pain relief. We aimed to determine whether children who receive dexamethasone or dexamethasone with NSAID are more likely to experience haemorrhage post-tonsillectomy. Randomized and non-randomized studies in which children undergoing tonsillectomy received dexamethasone or dexamethasone and NSAID were sought within bibliographic databases and selected tertiary sources. The risk of bias assessment and evaluation of haemorrhage rate data collection and reporting were assessed using the Cochrane Risk of Bias Tool and McHarm tool. Synthesis methods comprised pooled estimate of the effect of dexamethasone on the risk of haemorrhage rate using the Peto odds ratio (OR) method. The pooled estimate for haemorrhage rate in children who received dexamethasone was 6.2%, OR 1.41 (95% confidence interval 0.89-2.25, P=0.15). There was risk of bias and inconsistent data collection and reporting rates of haemorrhage in many of the included studies. Clinical heterogeneity was observed between studies. The pooled analysis did not demonstrate a statistically significant increase in the risk of post-tonsillectomy haemorrhage with dexamethasone with/without NSAID use in children. However, the majority of the included studies were not designed to investigate this endpoint, and thus large studies which are specifically designed to collect data on haemorrhage rate are needed.

Pressure effect on stabilities of self-interstitials in HCP-zirconium

The self-interstitial atoms (SIAs) mediate the evolution of micro-structures which is crucial in understanding the instabilities of hexagonal close packed (HCP) structures. Taking zirconium as a prototype, we investigate the pressure effect on the stabilities of SIAs using first-principles calculations based on density-functional theory. We found that the pressure greatly affects the stability of the SIAs. The SIAs in basal planes are more stable under pressure. The SIA configuration of the lowest formation energy changes from basal octahedral (BO) to octahedral (O) at a pressure of 21 GPa. The lowest formation enthalpy configuration switches from BO to S (split-dumbbell) at the pressure of 30 GPa. The formation volumes of SIAs decrease monotonically in response to an increase in pressure. Our results reveal that it is important to take pressure effects into account when predicting the micro-structural evolution of HCP structures.

Outstanding mechanical properties of monolayer MoS2 and its application in elastic energy storage

The structural and mechanical properties of graphene-like honeycomb monolayer structures of MoS2 (g-MoS2) under various large strains are investigated using density functional theory (DFT). g-MoS2 is mechanically stable and can sustain extra large strains: the ultimate strains are 0.24, 0.37, and 0.26 for armchair, zigzag, and biaxial deformation, respectively. The in-plane stiffness is as high as 120 N m(-1) (184 GPa equivalently). The third, fourth, and fifth order elastic constants are indispensable for accurate modeling of the mechanical properties under strains larger than 0.04, 0.07, and 0.13 respectively. The second order elastic constants, including in-plane stiffness, are predicted to monotonically increase with pressure while the Poisson ratio monotonically decreases with increasing pressure. With the prominent mechanical properties including large ultimate strains and in-plane stiffness, g-MoS2 is a promising candidate of elastic energy storage for clean energy. It possesses a theoretical energy storage capacity as high as 8.8 MJ L(-1) and 1.7 MJ kg(-1), or 476 W h kg(-1), larger than a Li-ion battery and is environmentally friendly.

New materials graphyne, graphdiyne, graphone, and graphane: review of properties, synthesis, and application in nanotechnology

Plenty of new two-dimensional materials including graphyne, graphdiyne, graphone, and graphane have been proposed and unveiled after the discovery of the “wonder material” graphene. Graphyne and graphdiyne are two-dimensional carbon allotropes of graphene with honeycomb structures. Graphone and graphane are hydrogenated derivatives of graphene. The advanced and unique properties of these new materials make them highly promising for applications in next generation nanoelectronics. Here, we briefly review their properties, including structural, mechanical, physical, and chemical properties, as well as their synthesis and applications in nanotechnology. Graphyne is better than graphene in directional electronic properties and charge carriers. With a band gap and magnetism, graphone and graphane show important applications in nanoelectronics and spintronics. Because these materials are close to graphene and will play important roles in carbon-based electronic devices, they deserve further, careful, and thorough studies for nanotechnology applications.

Transition between mechanisms of laser-induced field-free molecular orientation

The transition between two distinct mechanisms for the laser-induced field-free orientation of CO molecules is observed via measurements of orientation revival times and subsequent comparison to theoretical calculations. In the first mechanism, which we find responsible for the orientation of CO up to peak intensities of 8 × 10(13) W/cm(2), the molecules are impulsively oriented through the hyperpolarizability interaction. At higher intensities, asymmetric depletion through orientation-selective ionization is the dominant orienting mechanism. In addition to the clear identification of the two regimes of orientation, we propose that careful measurements of the onset of the orientation depletion mechanism as a function of the laser intensity will provide a relatively simple route to calibrating absolute rates of nonperturbative strong-field molecular ionization.

Monte carlo based simulation for evaluating optode fiber placement in prefrontal cortex imaging of motor skills during surgical training

This study investigates the sensitivity of fiber placement positioning for the purpose of prefrontal cortex imaging using functional near-infrared spectroscopy (fNIRS). Results indicate that our proposed optode placement has higher scaled-absorption sensitivity than the traditional International 10-20 system for optode placement based on Monte Carlo simulations.

Toward the development of a virtual electrosurgery training simulator

We propose a principled approach to the design of a computer-based, virtual reality simulator specifically for electrosurgical training. The design builds on the Fundamental Use of Surgical Energy (FUSE) program's didactic curriculum and the results of a survey of domain experts on the roles of cognitive knowledge and hands-on training for a selection of electrosurgery tasks. The resulting design focuses narrowly on the tissue effects caused during electrosurgery and the identified physician-controllable factors causing those effects.

Development of a Virtual Reality Simulator for Natural Orifice Translumenal Endoscopic Surgery (NOTES) Cholecystectomy Procedure

The first virtual-reality-based simulator for Natural Orifice Translumenal Endoscopic Surgery (NOTES) is developed called the Virtual Translumenal Endoscopic Surgery Trainer (VTEST^TM). VTEST^TM aims to simulate hybrid NOTES cholecystectomy procedure using a rigid scope inserted through the vaginal port. The hardware interface is designed for accurate motion tracking of the scope and laparoscopic instruments to reproduce the unique hand-eye coordination. The haptic-enabled multimodal interactive simulation includes exposing the Calot's triangle and detaching the gall bladder while performing electrosurgery. The developed VTEST^TM was demonstrated and validated at NOSCAR 2013.

Thermomechanical properties and equation of state for the γ-polymorph of hexahydro-1,3,5-trinitro-1,3,5-triazine

This work predicts the elastic modulus tensor, equation of state, and coefficients of thermal expansion at all stable thermodynamic states for γ-RDX. The work provides substantial material information for continuum modeling of RDX.

A framework for providing cognitive feedback in surgical simulators

Providing cognitive feedback in a virtual reality simulator during training is essential for subjects to correct and learn proper techniques. In this work, we have developed a framework to identify key skills and cognitive knowledge required to perform a task and methods to provide to the user. The framework was verified by implementing a test case scenario with the peg transfer task of the FLS.

Kinematic Measures for Evaluating Surgical Skills in Natural Orifice Translumenal Endoscopic Surgery (NOTES)

Natural Orifice Translumenal Endoscopic Surgery is an emerging procedure that requires training and adoption to be successful. Currently no objective performance metrics exist for evaluating skills for NOTES. In this work, we have improved upon our previous study on objective performance metrics using kinematic measures by introducing two new measures, the flex and the roll and recruiting more subjects to increase the statistical power. The measures were evaluated in a transgastric NOTES appendectomy procedure performed with ex-vivo organs using the EASIE-R^TM trainer box. Four motion tracking sensors attached to an endoscope were used to measure the scope position and orientation to compute the kinematic measures. Results from our study showed that completion time, economy of motion, jerk and roll of the scope are valid kinematic measures to differentiate between expert and novice NOTES surgeons.

pWeb: A High-Performance, Parallel-Computing Framework for Web-Browser-Based Medical Simulation

This work presents a pWeb - a new language and compiler for parallelization of client-side compute intensive web applications such as surgical simulations. The recently introduced HTML5 standard has enabled creating unprecedented applications on the web. Low performance of the web browser, however, remains the bottleneck of computationally intensive applications including visualization of complex scenes, real time physical simulations and image processing compared to native ones. The new proposed language is built upon web workers for multithreaded programming in HTML5. The language provides fundamental functionalities of parallel programming languages as well as the fork/join parallel model which is not supported by web workers. The language compiler automatically generates an equivalent parallel script that complies with the HTML5 standard. A case study on realistic rendering for surgical simulations demonstrates enhanced performance with a compact set of instructions.

A Decoupled 2 DOF Force Feedback Mechanism for the Virtual Translumenal Endoscopic Surgical Trainer (VTEST

Natural orifice translumenal endoscopic surgery (NOTES) is a minimally invasive procedure which utilizes the body's natural orifices to gain access to the peritoneal cavity. The VTEST is a virtual reality NOTES cholecystectomy simulator being built at the CeMSIM at RPI. We have developed a 2 DOF decoupled haptic device, which can provide translational and rotational haptic feedback to the user handling the flexible endoscope. Preliminary results indicate the device is capable of providing realistic feedback to the user while operating the device.

Development of Extracorporeal Suturing Simulation in Virtual Basic Laparoscopic Skill Trainer (VBLaST

This paper presents the development of extracorporeal suturing simulation in Virtual Basic Laparoscopic Skill Trainer (VBLaST^©). A novel hardware interface is designed to allow the user to perform the physical action of trying a knot and seamlessly integrate the knot into the virtual simulation.

A physics-based algorithm for real-time simulation of electrosurgery procedures in minimally invasive surgery

BACKGROUND

High-frequency electricity is used in the majority of surgical interventions. However, modern computer-based training and simulation systems rely on physically unrealistic models that fail to capture the interplay of the electrical, mechanical and thermal properties of biological tissue.

METHODS

We present a real-time and physically realistic simulation of electrosurgery by modelling the electrical, thermal and mechanical properties as three iteratively solved finite element models. To provide subfinite-element graphical rendering of vaporized tissue, a dual-mesh dynamic triangulation algorithm based on isotherms is proposed. The block compressed row storage (BCRS) structure is shown to be critical in allowing computationally efficient changes in the tissue topology due to vaporization.

RESULTS

We have demonstrated our physics-based electrosurgery cutting algorithm through various examples. Our matrix manipulation algorithms designed for topology changes have shown low computational cost.

CONCLUSIONS

Our simulator offers substantially greater physical fidelity compared to previous simulators that use simple geometry-based heat characterization.

Energy dependence of the transverse momentum distributions of charged particles in pp collisions measured by ALICE

Differential cross sections of charged particles in inelastic pp collisions as a function of p_T have been measured at [Formula: see text] at the LHC. The p_T spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual [Formula: see text] cannot be described by NLO-pQCD, the relative increase of cross section with [Formula: see text] is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at [Formula: see text] up to p_T=50 GeV/c as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus collisions.

Directed flow of charged particles at midrapidity relative to the spectator plane in Pb-Pb collisions at √(s(NN))=2.76 TeV

The directed flow of charged particles at midrapidity is measured in Pb-Pb collisions at √(s(NN))=2.76 TeV relative to the collision symmetry plane defined by the spectator nucleons. A negative slope of the rapidity-odd directed flow component with approximately 3 times smaller magnitude than found at the highest RHIC energy is observed. This suggests a smaller longitudinal tilt of the initial system and disfavors the strong fireball rotation predicted for the LHC energies. The rapidity-even directed flow component is measured for the first time with spectators and found to be independent of pseudorapidity with a sign change at transverse momenta p(T) between 1.2 and 1.7  GeV/c. Combined with the observation of a vanishing rapidity-even p(T) shift along the spectator deflection this is strong evidence for dipolelike initial density fluctuations in the overlap zone of the nuclei. Similar trends in the rapidity-even directed flow and the estimate from two-particle correlations at midrapidity, which is larger by about a factor of 40, indicate a weak correlation between fluctuating participant and spectator symmetry planes. These observations open new possibilities for investigation of the initial conditions in heavy-ion collisions with spectator nucleons.

A Logarithmic Complexity Floating Frame of Reference Formulation with Interpolating Splines for Articulated Multi-Flexible-Body Dynamics

An interpolating spline-based approach is presented for modeling multi-flexible-body systems in the divide-and-conquer (DCA) scheme. This algorithm uses the floating frame of reference formulation and piecewise spline functions to construct and solve the non-linear equations of motion of the multi-flexible-body system undergoing large rotations and translations. The new approach is compared with the flexible DCA (FDCA) that uses the assumed modes method [1]. The FDCA, in many cases, must resort to sub-structuring to accurately model the deformation of the system. We demonstrate, through numerical examples, that the interpolating spline-based approach is comparable in accuracy and superior in efficiency to the FDCA. The present approach is appropriate for modeling flexible mechanisms with thin 1D bodies undergoing large rotations and translations, including those with irregular shapes. As such, the present approach extends the current capability of the DCA to model deformable systems. The algorithm retains the theoretical logarithmic complexity inherent in the DCA when implemented in parallel.

K(S)0 and Λ production in Pb-Pb collisions at √(s(NN))=2.76 TeV

The ALICE measurement of K(S)(0) and Λ production at midrapidity in Pb-Pb collisions at √(s(NN))=2.76 TeV is presented. The transverse momentum (p(T)) spectra are shown for several collision centrality intervals and in the p(T) range from 0.4 GeV/c (0.6 GeV/c for Λ) to 12 GeV/c. The p(T) dependence of the Λ/K(S)(0) ratios exhibits maxima in the vicinity of 3 GeV/c, and the positions of the maxima shift towards higher p(T) with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate p(T) is not observed in pp interactions at √s=0.9 TeV and at √s=7 TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured p(T) spectra above 2 GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of p(T), models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the p(T) dependence of the Λ/K(S)(0) ratio.

Charmonium and e+e- pair photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at [Formula: see text]

The ALICE Collaboration at the LHC has measured the J/ψ and ψ' photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at [Formula: see text]. The charmonium is identified via its leptonic decay for events where the hadronic activity is required to be minimal. The analysis is based on an event sample corresponding to an integrated luminosity of about 23 μb-1. The cross section for coherent and incoherent J/ψ production in the rapidity interval -0.9 Collapse

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Relationship of body compositional and nutritional parameters with blood pressure in adults

BACKGROUND

Obesity has been regarded as a single best predictor and major controllable contributor to hypertension. The present study aimed to assess the relationship between body compositional and nutritional parameters with blood pressure in rural Bengalee adults.

METHODS

Anthropometric measures, blood pressure and nutritional parameters were measured in 522 rural Bengalee adults using standard protocols. Receiver operating characteristic analysis was carried out to identify cut-off values of body mass index (BMI) and percentage of body fat (BF%) as associated factors of hypertension and hypotension.

RESULTS

Most of the subjects were normotensive. However, a notable percentage had hypertension (males: 21.86%; females: 15.27%), although the prevalence of hypotension was low (males: 10.53%; females: 8.73%). Obesity indicators were significantly higher in hypertensive individuals than hypotensive and normotensive individuals. All anthropometric parameters and obesity indicators were significantly correlated (P < 0.001) with blood pressure. Blood pressure increased steadily from being underweight through to normal and then to overweight/obese individuals. There were significant differences in the percentage of hypertension and hypotension between nutritional categories. Blood pressure had significant positive correlation with energy, carbohydrate and fat intake, whereas protein and calcium were negatively associated with blood pressure. The suggested cut-off values of BMI and BF%, which were taken as associated factors of hypertension, were 21.86 kg m⁻² and 20.31%, and those of hypotension were 18.18 kg m⁻² and 13.3%, respectively.

CONCLUSIONS

In lean rural Bengalee populations, high BMI levels may be associated with an increased risk of hypertension. The cut-off values of BMI and BF% in the present study suggested associated factors for cardiovascular risk factors and these values may be of help with respect to reducing mean population blood pressure levels.