Computer simulations of cosmic-ray diffusion near supernova remnant shock waves

A plasma simulation model was used to study the resonant interactions between streaming cosmic-ray ions and a self-consistent spectrum of Alfven waves, such as might exist in the interstellar medium upstream of a supernova remnant shock wave. The computational model is a hybrid one, in which the background interstellar medium is an MHD fluid and the cosmic-rays are discrete kinetic particles. The particle sources for the electromagnetic fields are obtained by averaging over the fast cyclotron motions. When the perturbed magnetic field is larger than 10 percent of the background field, the macro- and microphysics are no longer correctly predicted by quasi-linear theory. The particles are trapped by the waves and show sharp jumps in their pitch-angles relative to the background magnetic field, and the effective ninety-degree scattering time for diffusion parallel to the background magnetic field is reduced to between 5 and 30 cyclotron periods. Simulation results suggest that Type 1 supernova remnants may be the principal sites of cosmic ray acceleration

Generating Polarization-Entangled Photon Pairs with Arbitrary Joint Spectrum

We present a scheme for generating polarization-entangled photons pairs with arbitrary joint spectrum. Specifically, we describe a technique for spontaneous parametric down-conversion in which both the center frequencies and the bandwidths of the down-converted photons may be controlled by appropriate manipulation of the pump pulse. The spectral control offered by this technique permits one to choose the operating wavelengths for each photon of a pair based on optimizations of other system parameters (loss in optical fiber, photon counter performance, etc.). The combination of spectral control, polarization control, and lack of group-velocity matching conditions makes this technique particularly well-suited for a distributed quantum information processing architecture in which integrated optical circuits are connected by spans of optical fiber.Comment: 6 pages, 3 figure

Symmetric Autocompensating Quantum Key Distribution

We present quantum key distribution schemes which are autocompensating (require no alignment) and symmetric (Alice and Bob receive photons from a central source) for both polarization and time-bin qubits. The primary benefit of the symmetric configuration is that both Alice and Bob may have passive setups (neither Alice nor Bob is required to make active changes for each run of the protocol). We show that both the polarization and the time-bin schemes may be implemented with existing technology. The new schemes are related to previously described schemes by the concept of advanced waves.Comment: 4 pages, 2 figur

Force of Beauty or Object of Desire? The Priming Effects of Makeup Video Advertisements on Self-Objectification in College Women

Women are too often valued for their beauty and have shifted their focus from character to body improvement (Brumberg, 1998). Objectification theory (Frederickson & Roberts, 1997) posits that sexual objectification socializes females to evaluate themselves based on looks. Self-objectification is the attempt to control this external perception by monitoring one’s physical appearance. Women are more likely to think “How do I look?” than “What am I capable of?” The priming effects of positive and negative body-focused makeup advertisements on college-aged women’s level of self-objectification were examined in two separate studies. In study one, 87 participants viewing positive vs. negative advertisements reported more traits and abilities; this was especially true for high self-objectifiers. Participants viewing positive advertisements reported more positive emotions, suggesting the salutary role that positive messaging may play. Results were replicated in study two, with 172 participants who viewed positive vs. negative advertisements reporting significantly fewer body shape statements, more trait and abilities, as well as more physical competence statements. In addition, individuals who viewed advertisements with non-objectifying content responded with a significantly greater number of positively valenced statements and significantly fewer negative statements about themselves in comparison to women who viewed objectifying advertisements. These results suggest that marketers should eschew advertising that sexually objectifies women and promotes unattainable beauty goals. Future research should evaluate cumulative and long-term effects of advertisement and examine whether exposure that leads to lower levels of objectification also minimizes negative consequences associated with objectifying media influences (e.g., body shame, depression, eating disorder)

Magnetically-controlled velocity selection in a cold atom sample using stimulated Raman transitions

We observe velocity-selective two-photon resonances in a cold atom cloud in the presence of a magnetic field. We use these resonances to demonstrate a simple magnetometer with sub-mG resolution. The technique is particularly useful for zeroing the magnetic field and does not require any additional laser frequencies than are already used for standard magneto-optical traps. We verify the effects using Faraday rotation spectroscopy.Comment: 5 pages, 6 figure

Map equation for link community

Community structure exists in many real-world networks and has been reported being related to several functional properties of the networks. The conventional approach was partitioning nodes into communities, while some recent studies start partitioning links instead of nodes to find overlapping communities of nodes efficiently. We extended the map equation method, which was originally developed for node communities, to find link communities in networks. This method is tested on various kinds of networks and compared with the metadata of the networks, and the results show that our method can identify the overlapping role of nodes effectively. The advantage of this method is that the node community scheme and link community scheme can be compared quantitatively by measuring the unknown information left in the networks besides the community structure. It can be used to decide quantitatively whether or not the link community scheme should be used instead of the node community scheme. Furthermore, this method can be easily extended to the directed and weighted networks since it is based on the random walk.Comment: 9 pages,5 figure

A Defined Network of Fast-Spiking Interneurons in Orbitofrontal Cortex: Responses to Behavioral Contingencies and Ketamine Administration

Orbitofrontal cortex (OFC) is a region of prefrontal cortex implicated in the motivational control of behavior and in related abnormalities seen in psychosis and depression. It has been hypothesized that a critical mechanism in these disorders is the dysfunction of GABAergic interneurons that normally regulate prefrontal information processing. Here, we studied a subclass of interneurons isolated in rat OFC using extracellular waveform and spike train analysis. During performance of a goal-directed behavioral task, the firing of this class of putative fast-spiking (FS) interneurons showed robust temporal correlations indicative of a functionally coherent network. FS cell activity also co-varied with behavioral response latency, a key indicator of motivational state. Systemic administration of ketamine, a drug that can mimic psychosis, preferentially inhibited this cell class. Together, these results support the idea that OFC–FS interneurons form a critical link in the regulation of motivation by prefrontal circuits during normal and abnormal brain and behavioral states

Practice of and Barriers to Prevention by Secondary School Athletic Trainers

Purpose: Prevention is a key aspect of care from athletic trainers. There is limited research on the practice strategies employed to prevent injury by secondary school athletic trainers (SSATs). The purpose of this study was to describe the prevention practice strategies and barriers faced by secondary school athletic trainers. Methods: Athletic trainers (n=3010) were recruited from secondary schools through e-mails provided by the national professional organization database. Secondary school athletic trainers were surveyed on their self-reported prevention practices and barriers using a web-based survey platform. Respondents were 28±3 years, predominantly female (n=260/359, 72.4%), with about 5 years (±2yrs) of clinical experience. The survey contained prevention strategies items with tasks from Domain 1 of the Board of Certification Role Delineation Study (6th ed.) that relates to athletic training clinical practice. Barrier items were developed from previous literature about implementing evidence-based practice strategies. Partial data (completion rate=359/473, 75.9%) was used for the analyses. Data were analyzed by using frequencies, medians with percentiles, means, and standard deviations. Results: The least frequently practiced environmental illness monitoring techniques and addressing patient-specific nutritional needs were identified. In contrast, secondary school athletic trainers most frequently practiced compliance for both equipment maintenance and maintaining a clean facility. The most common ‘always practiced’ skills align with Task 102, 103, and 104 in Domain 1 of the Board of Certification Role Delineation Study. These include pre-participation and screening, personal protective equipment, and maintaining treatment and rehabilitation areas through regulatory standards. A lack of time, workload, player compliance, available space, and coach support were the most commonly cited barriers to prevention practice. Conclusions: Overall, secondary school athletic trainers engaged in prevention strategies frequently, yet external factors were barriers to implementation. The consistent and continual practice of prevention skills are essential to risk mitigation. As a result, always practicing the skill is essential and should not be completed as an occasional duty of the athletic training. As many prevention strategies are required for all patient encounters, the frequency of task performance must improve for clinical practice