Evaporative depolarization and spin transport in a unitary trapped Fermi gas

We consider a partially spin-polarized atomic Fermi gas in a high-aspect-ratio trap, with a flux of predominantly spin-up atoms exiting the center of the trap. We argue that such a scenario can be produced by evaporative cooling, and we find that it can result in a substantially non-equilibrium polarization pattern for typical experimental parameters. We offer this as a possible explanation for the quantitative discrepancies in recent experiments on spin-imbalanced unitary Fermi gases.Comment: 6 pages, 3 figures; published versio

Parental awareness, Knowledge, and Attitude towards Nitrous oxide sedation and Protective stabilization in children of North Kerala: A questionnaire based study

To assess the Parental awareness, knowledge and attitude in North Kerala population about Conscious sedation and protective stabilization as behaviour management techniques during dental treatment

Trimers, molecules and polarons in imbalanced atomic Fermi gases

We consider the ground state of a single "spin-down" impurity atom interacting attractively with a "spin-up" atomic Fermi gas. By constructing variational wave functions for polarons, molecules and trimers, we perform a detailed study of the transitions between each of these dressed bound states as a function of mass ratio $r=m_\uparrow/m_\downarrow$ and interaction strength. We find that the presence of a Fermi sea enhances the stability of the $p$-wave trimer, which can be viewed as a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) molecule that has bound an additional majority atom. For sufficiently large $r$, we find that the transitions lie outside the region of phase separation in imbalanced Fermi gases and should thus be observable in experiment, unlike the well-studied equal-mass case.Comment: 5 pages, 2 figure

The effect of on/off indicator design on state confusion, preference, and response time performance, executive summary

Investigated are five designs of software-based ON/OFF indicators in a hypothetical Space Station Power System monitoring task. The hardware equivalent of the indicators used in the present study is the traditional indicator light that illuminates an ON label or an OFF label. Coding methods used to represent the active state were reverse video, color, frame, check, or reverse video with check. Display background color was also varied. Subjects made judgments concerning the state of indicators that resulted in very low error rates and high percentages of agreement across indicator designs. Response time measures for each of the five indicator designs did not differ significantly, although subjects reported that color was the best communicator. The impact of these results on indicator design is discussed

Spin-chain model of a many-body quantum battery

Recently, it has been shown that energy can be deposited on a collection of quantum systems at a rate that scales super-extensively. Some of these schemes for `quantum batteries' rely on the use of global many-body interactions that take the batteries through a correlated short cut in state space. Here, we extend the notion of a quantum battery from a collection of a priori isolated systems to a many-body quantum system with intrinsic interactions. Specifically, we consider a one-dimensional spin chain with physically realistic two-body interactions. We find that the spin-spin interactions can yield an advantage in charging power over the non-interacting case, and we demonstrate that this advantage can grow super-extensively when the interactions are long ranged. However, we show that, unlike in previous work, this advantage is a mean-field interaction effect that does not involve correlations and that relies on the interactions being intrinsic to the battery.Comment: 9 pages, 6 figure

Maternal risk factors and perinatal outcome in meconium stained amniotic fluid: a cross sectional study

Background: Meconium staining of amniotic fluid has long been regarded as a sign of fetal distress and fetal asphyxia. Although exact cause is unknown, meconium is thought to be passed from fetal gastro-intestinal tract as a response to hypoxia, mesenteric vasoconstriction induced gut hyper peristalsis, vagal stimulation and normal physiologic function of a mature fetus. Overall frequency has ranged from 5 to 24.6%. Present study is undertaken to detect incidence, mode of delivery, fetal heart rate variability and neonatal outcome in neonates born through MSAF. The objective of the study was to maternal risk factors, mode of delivery and perinatal outcome in labors complicated with meconium stained amniotic fluid.Methods: This is a cross sectional study done at Government Medical College, Thrissur on term, singleton pregnancies complicated with meconium stained amniotic fluid satisfying the inclusion criteria. Patients detailed history, gestational age, per abdominal examination, per speculum and per vaginal examination, admission tests including intrapartum cardiotocography (CTG) was recorded in a predesigned proforma.Results: The age of the patients varied between above 19 and 30 years. Majority of the study population were 69.3% Primi gravidas. Out of 130 cases, 56.2% were grade 2 meconium stained liquor, 30.7% were grade 3 meconium stained and 13.1% were grade 1 meconium stained. Association between neonatal complications in relation to grades of meconium was found to be statistically significant (p = 0.001). NICU admission was 24.7% in grade 2 meconium group. Hypoxic Ischemic encephalopathy was high in grade 3 meconium group, 45%. Majority of babies born through grade 1 meconium were asymptomatic and 10% of babies in grade 3 meconium groups were asymptomatic. Meconium aspiration syndrome, Respiratory distress were more in babies born through deliveries complicated with grade 3 meconium.Conclusions: The study indicated meconium stained amniotic fluid during labour increases the prevalence of abnormal intrapartum CTG, Caesarean section, lower Apgar score, increased duration of NICU and hospital stay, poor perinatal outcome and non-significant difference in incidence of lower birth weight in babies

Effects of spatially displaced feedback on remote manipulation tasks

Several studies have been performed to determine the effects on computer and direct manipulation task performance when viewing conditions are spatially displaced. Whether results from these studies can be directly applied to remote manipulation tasks is quenstionable. The objective of this evaluation was to determine the effects of reversed, inverted, and inverted/reversed views on remote manipulation task performance using two 3-Degree of Freedom (DOF) hand controllers and a replica position hand controller. Results showed that trials using the inverted viewing condition showed the worst performance, followed by the inverted/reversed view and the reversed view when using the 2x3 DOF. However, these differences were not significant. The inverted and inverted/reversed viewing conditions were significantly worse than the normal and reversed viewing conditions when using the Kraft Replica. A second evaluation was conducted in which additional trials were performed with each viewing condition to determine the long term effects of spatially displaced views on task performance for the hand controllers. Results of the second evaluation indicated that there was more of a difference in performance between the perturbed viewing conditions and the normal viewing condition with the Kraft Replica than with the 2x3 DOF

Evaluation of force-torque displays for use with space station telerobotic activities

Recent experiments which addressed Space Station remote manipulation tasks found that tactile force feedback (reflecting forces and torques encountered at the end-effector through the manipulator hand controller) does not improve performance significantly. Subjective response from astronaut and non-astronaut test subjects indicated that force information, provided visually, could be useful. No research exists which specifically investigates methods of presenting force-torque information visually. This experiment was designed to evaluate seven different visual force-torque displays which were found in an informal telephone survey. The displays were prototyped in the HyperCard programming environment. In a within-subjects experiment, 14 subjects nullified forces and torques presented statically, using response buttons located at the bottom of the screen. Dependent measures included questionnaire data, errors, and response time. Subjective data generally demonstrate that subjects rated variations of pseudo-perspective displays consistently better than bar graph and digital displays. Subjects commented that the bar graph and digital displays could be used, but were not compatible with using hand controllers. Quantitative data show similar trends to the subjective data, except that the bar graph and digital displays both provided good performance, perhaps do to the mapping of response buttons to display elements. Results indicate that for this set of displays, the pseudo-perspective displays generally represent a more intuitive format for presenting force-torque information

Phase separation and collapse in Bose-Fermi mixtures with a Feshbach resonance

We consider a mixture of single-component bosonic and fermionic atoms with an interspecies interaction that is varied using a Feshbach resonance. By performing a mean-field analysis of a two-channel model, which describes both narrow and broad Feshbach resonances, we find an unexpectedly rich phase diagram at zero temperature: Bose-condensed and non-Bose-condensed phases form a variety of phase-separated states that are accompanied by both critical and tricritical points. We discuss the implications of our results for the experimentally observed collapse of Bose-Fermi mixtures on the attractive side of the Feshbach resonance, and we make predictions for future experiments on Bose-Fermi mixtures close to a Feshbach resonance.Comment: 7 pages, 3 figures. Extended versio