Method of carbonizing polyacrylonitrile fibers

This invention relates to a method of carbonizing polyacrylonitrile fibers by exposing the fibers at an elevated temperature to an oxidizing atmosphere; then exposing the oxidized fibers to an atmosphere of an inert gas such as nitrogen containing a carbonaceous material such as acetylene. The fibers are preferably treated with an organic compound, for example benzoic acid, before the exposure to an oxidizing atmosphere. The invention also relates to the resulting fibers. The treated fibers have enhanced tensile strength

A Review of Best Practices for Monitoring and Improving Inpatient Pediatric Patient Experiences.

ContextAchieving high-quality patient-centered care requires assessing patient and family experiences to identify opportunities for improvement. With the Child Hospital Consumer Assessment of Healthcare Providers and Systems Survey, hospitals can assess performance and make national comparisons of inpatient pediatric experiences. However, using patient and family experience data to improve care remains a challenge.ObjectiveWe reviewed the literature on best practices for monitoring performance and undertaking activities aimed at improving pediatric patient and family experiences of inpatient care.Data sourcesWe searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and PsychINFO.Study selectionWe included (1) English-language peer-reviewed articles published from January 2000 to April 2019; (2) articles based in the United States, United Kingdom, or Canada; (3) articles focused on pediatric inpatient care; (4) articles describing pediatric patient and family experiences; and (5) articles including content on activities aimed at improving patient and family experiences. Our review included 25 articles.Data extractionTwo researchers reviewed the full article and abstracted specific information: country, study aims, setting, design, methods, results, Quality Improvement (QI) initiatives performed, internal reporting description, best practices, lessons learned, barriers, facilitators and study implications for clinical practice, patient-experience data collection, and QI activities. We noted themes across samples and care settings.ResultsWe identified 10 themes of best practice. The 4 most common were (1) use evidence-based approaches, (2) maintain an internal system that communicates information and performance on patient and family experiences to staff and hospital leadership, (3) use experience survey data to initiate and/or evaluate QI interventions, and (4) identify optimal times (eg, discharge) and modes (eg, print) for obtaining patient and family feedback. These correspond to adult inpatient best practices.ConclusionsBoth pediatric and adult inpatient best practices rely on common principles of culture change (such as evidence-based clinical practice), collaborative learning, multidisciplinary teamwork, and building and/or supporting a QI infrastructure that requires time, money, collaboration, data tracking, and monitoring. QI best practices in both pediatric and adult inpatient settings commonly rely on identifying drivers of overall ratings of care, rewarding staff for successful implementation, and creating easy-to-use and easy-to-access planning and QI tools for staff

Fluctuational susceptibility of ultracold bosons in the vicinity of condensation

We study the behaviour of ultracold bosonic gas in the critical region above the Bose-Einstein condensation in the presence of an artificial magnetic field, $B_\mathrm{art}$. We show that the condensate fluctuations above the critical temperature $T_c$ cause the fluctuational susceptibility, $\chi _\mathrm{fl}$, of a uniform gas to have a stronger power-law divergence than in an analogous superconducting system. Measuring such a divergence opens new ways of exploring critical properties of the ultracold gas and an opportunity of an accurate determination of $T_c$. We describe a method of measuring $\chi _\mathrm{fl}$ which requires a constant gradient in $B_\mathrm{art}$ and suggest a way of creating such a field in experiment.Comment: 5 pages, 3 figures, 5 pages of Supplement; the text is rewritten and rearranged, and the figures are modifie

Algorithm Based Fault Tolerance in Massively Parallel Systems

An A complex computer system consists of billions of transistors, miles of wires, and many interactions with an unpredictable environment. Correct results must be produced despite faults that dynamically occur in some of these components. Many techniques have been developed for fault tolerant computation. General purpose methods are independent of the application, yet incur an overhead cost which may be unacceptable for massively parallel systems. Algorithm-specific methods, which can operate at lower cost, are a developing alternative [1, 72]. This paper first reviews the general-purpose approach and then focuses on the algorithm-specific method, with an eye toward massively parallel processors. Algorithm-based fault tolerance has the attraction of low overhead; furthermore it addresses both the detection and also the correction problems. The principle is to build low-cost checking and correcting mechanism based exclusively on the redundancies inherent in the system

Low-Temperature Decoherence of Qubit Coupled to Background Charges

We have found an exact expression for the decoherence rate of a Josephson charge qubit coupled to fluctuating background charges. At low temperatures $T$ the decoherence rate ${\Gamma}$ is linear in $T$ while at high temperatures it saturates in agreement with a known classical solution which, however, reached at surprisingly high $T$. In contrast to the classical picture, impurity states spread in a wide interval of energies ($\gg T$) may essentially contribute to ${\Gamma}$.Comment: Both figures are changed to illustrate a more generic case of impurity states spread in wide interval of energies. Some changes have been made to the abstract and the introductio

Deciding to be Distracted

This project investigated the decision process involved in a driver’s willingness to engage in various technology-related and non-technology tasks. The project included focus groups and an on-road study, both employing participants who used in-vehicle technologies to at least some degree, from four age groups: teen, young, middle, and older. The focus groups discussed the perceptions, motivations, attitudes, and decision factors that underlie driver choices. The on-road study had two phases: an on-road drive and a take-home booklet. Participants drove their own vehicles over a specified route. They did not actually engage in in-vehicle tasks, but at specified points they rated their willingness to engage in some specific task at that time and place. Eighty-one different situations (combination of in-vehicle task and driving circumstances) were included. Further information was collected in the take-home booklet regarding the participant’s familiarity with various in-vehicle technologies, additional situations for willingness and risk ratings, stated reasons underlying ratings, and self-ratings of certain aspects of driving behavior and decisionmaking style. Together, the focus groups and on-road study provided complementary findings about how drivers decide when to engage in potentially distracting tasks. Driver willingness to engage in various in-vehicle tasks was related to technology type, specific task attributes, driving conditions, personal motivations, driving style, and decision style. Specific project findings were related to potential countermeasure approaches, including public education; driver or device user training; user interface design; needs for warnings and information; criteria for function lock-outs; and driver assist system criteria

Impurity Scattering in Luttinger Liquid with Electron-Phonon Coupling

We study the influence of electron-phonon coupling on electron transport through a Luttinger liquid with an embedded weak scatterer or weak link. We derive the renormalization group (RG) equations which indicate that the directions of RG flows can change upon varying either the relative strength of the electron-electron and electron-phonon coupling or the ratio of Fermi to sound velocities. This results in the rich phase diagram with up to three fixed points: an unstable one with a finite value of conductance and two stable ones, corresponding to an ideal metal or insulator.Comment: 4 pages, 2 figure

Superfluidity of "dirty" indirect excitons and magnetoexcitons in two-dimensional trap

The superfluid phase transition of bosons in a two-dimensional (2D) system with disorder and an external parabolic potential is studied. The theory is applied to experiments on indirect excitons in coupled quantum wells. The random field is allowed to be large compared to the dipole-dipole repulsion between excitons. The slope of the external parabolic trap is assumed to change slowly enough to apply the local density approximation (LDA) for the superfluid density, which allows us to calculate the Kosterlitz-Thouless temperature $T_{c}(n(r))$ at each local point $r$ of the trap. The superfluid phase occurs around the center of the trap ($\mathbf{r}=0$) with the normal phase outside this area. As temperature increases, the superfluid area shrinks and disappears at temperature $T_{c}(n(r=0))$. Disorder acts to deplete the condensate; the minimal total number of excitons for which superfluidity exists increases with disorder at fixed temperature. If the disorder is large enough, it can destroy the superfluid entirely. The effect of magnetic field is also calculated for the case of indirect excitons. In a strong magnetic field $H$, the superfluid component decreases, primarily due to the change of the exciton effective mass.Comment: 13 pages, 3 figure

Boundedness of Pseudodifferential Operators on Banach Function Spaces

We show that if the Hardy-Littlewood maximal operator is bounded on a separable Banach function space $X(\mathbb{R}^n)$ and on its associate space $X'(\mathbb{R}^n)$, then a pseudodifferential operator $\operatorname{Op}(a)$ is bounded on $X(\mathbb{R}^n)$ whenever the symbol $a$ belongs to the H\"ormander class $S_{\rho,\delta}^{n(\rho-1)}$ with $0<\rho\le 1$, $0\le\delta<1$ or to the the Miyachi class $S_{\rho,\delta}^{n(\rho-1)}(\varkappa,n)$ with $0\le\delta\le\rho\le 1$, $0\le\delta0$. This result is applied to the case of variable Lebesgue spaces $L^{p(\cdot)}(\mathbb{R}^n)$.Comment: To appear in a special volume of Operator Theory: Advances and Applications dedicated to Ant\'onio Ferreira dos Santo