Solar Flare 1/f Fluctuations from Amplitude-Modulated Five-Minute Oscillation.

We first report that the solar flare time sequence exhibits a fluctuation characterized by its power spectral density being inversely proportional to the signal frequency. This is the 1/f fluctuation, or pink noise, observed ubiquitously in nature. Using GOES16 data, we found that low-energy flares (E≤Emean) display 1/f fluctuations, whereas high-energy flares (E>Emean) show a flat spectrum. Furthermore, we found that the timing sequence of the flares reveals clearer 1/f fluctuations. These observations suggest that the solar flare 1/f fluctuations are associated with low-energy phenomena. We investigated the origin of these 1/f fluctuations based on our recent hypothesis: 1/f fluctuations arise from amplitude modulation and demodulation. We propose that this amplitude modulation is encoded by the resonance with the solar five-minute oscillation (SFO) and demodulated by magnetic reconnections. We partially demonstrate this scenario by analyzing the SFO eigenmodes resolving the frequency degeneration in the azimuthal order number m using the solar rotation and resonance. Given the robust nature of 1/f fluctuations, we speculated that the solar flare 1/f fluctuations may be inherited by the various phenomena around the Sun, such as the sunspot numbers and cosmic rays. In addition, we draw parallels between solar flares and earthquakes, both exhibiting 1/f fluctuations. Interestingly, the analysis applied to solar flares can also be adapted to earthquakes if we read the SFO as Earth's free oscillation and magnetic reconnections as fault ruptures. Moreover, we point out the possibility that the same analysis also applies to the activity of a black hole/disk system if we read the SFO as the quasi-periodic oscillation of a black hole.

A simple model for pink noise from amplitude modulations.

We propose a simple model for the origin of pink noise (or 1/f fluctuation) based on the waves with accumulating frequencies. These waves arise spontaneously in a system with synchronization, resonance, and infrared divergence. Many waves with accumulating frequencies can produce signals of arbitrary small frequencies from a system of small size. This beat mechanism can be understood as amplitude modulation. The pink noise can appear after the demodulation process, which produces a variety of pink noise in many fields. The pink noise thus formed from the beat has nothing to do with dissipation or long-time memory. We also suggest new ways of looking at pink noise in earthquakes, solar flares, and stellar activities.

The association between global health training and underserved care: early findings from two longstanding tracks.

BACKGROUND AND OBJECTIVES: Global health tracks (GHTs) improve knowledge and skills, but their impact on career plans is unclear. The objective of this analysis was to determine whether GHT participants are more likely to practice in underserved areas than nonparticipants. METHODS: In this retrospective cohort study, using the 2009 American Medical Association Masterfile, we assessed the practice location of the 480 graduates from 1980--2008 of two family medicine residencies-Residency 1 and Residency 2. The outcomes of interest were the percentage of graduates in health professional shortage areas (HPSAs), medically underserved areas (MUAs), rural areas, areas of dense poverty, or any area of underservice. RESULTS: Thirty-seven percent of Residency 1 participants and 20% of nonparticipants practiced in HPSAs; 69% of Residency 2 participants and 55.5% of nonparticipants practiced in areas of dense poverty. All other combined and within-residency differences were not statistically significant. CONCLUSIONS: These findings neither confirm nor refute the results of prior surveys suggesting that global health training is associated with increased interest in underserved care. Studies involving more GHTs and complimentary methods are needed to more precisely elucidate the impact of this training.

Self-organized relaxation in a collisionless gravitating system.

We propose the self-organized relaxation process which drives a collisionless self-gravitating system to the equilibrium state satisfying local virial (LV) relation. During the violent relaxation process, particles can move widely within the time interval as short as a few free-fall times, because of the effective potential oscillations. Since such particle movement causes further potential oscillations, it is expected that the system approaches the critical state where such particle activities, which we call gravitational fugacity, is independent of the local position as much as possible. Here we demonstrate that gravitational fugacity can be described as the functional of the LV ratio, which means that the LV ratio is a key ingredient estimating the particle activities against gravitational potential. We also demonstrate that the LV relation is attained if the LV ratio exceeds the critical value b=1 everywhere in the bound region during the violent relaxation process. The local region which does not meet this criterion can be trapped into the presaturated state. However, small phase-space perturbation can bring the inactive part into the LV critical state.

Effect of security threats on primary care access in Logar province, Afghanistan.

Security threats are a major concern for access to health care in many war-torn communities; however, there is little quantified data on actual access to care in rural communities during war. Kinderberg International e.V. provided primary care in rural Logar province, Afghanistan, for these three years in eight districts until they were integrated into the new health care structure led by the Ministry of Health in early 2005. We examined the number of patients visiting our clinic before and during the security threats related to the parliamentary election and subsequent national assembly in 2004. The number of patients declined in remote clinics while the number increased in central locations. This finding has an important practical implication: the monitoring of access to care should include remote clinics, otherwise it may potentially underestimate compromised access to health care due to security threats.

Need for "conflict version" of primary surgery: war surgery in the era of low-intensity conflicts.

The conventional wars between nations have widely been replaced by low-intensity conflicts within nations today, resulting in different patterns of injuries and practice of surgical care. A blurred front line, protracted durations of violence, indiscriminant fighting, and the emergence of specific surgical problems characterize low-intensity conflicts. In protracted conflicts with limited resources, surgical outcomes depend on many factors other than surgical skills, such as social/cultural values and economical feasibility. This paper examines how the characteristics of current conflicts affect surgical practice and will address key issues to evolve care to adapt to these changes. Key issues are (1) need for comprehensive surgical skills, (2) importance of improving local capacities, (3) long-term impact of trauma, and (4) limited access to information required to improve surgical skills.

Local virial relation for self-gravitating system.

We demonstrate that the quasi-equilibrium state in a self-gravitating N-body system after cold collapse is uniquely characterized by the local virial relation using numerical simulations. Conversely, assuming the constant local virial ratio and Jeans equation for a spherically steady-state system, we investigate the full solution space of the problem under the constant anisotropy parameter and obtain some relevant solutions. Specifically, the local virial relation always provides a solution which has a power-law density profile in both the asymptotic regions r --> 0 and infinity. This type of solution is commonly observed in many numerical simulations. Only the anisotropic velocity dispersion controls this asymptotic behavior of density profile.

Universal non-Gaussian velocity distribution in violent gravitational processes.

We study the velocity distribution in spherical collapses and cluster-pair collisions by use of N -body simulations. Reflecting the violent gravitational processes, the velocity distribution of the resultant quasistationary state generally becomes non-Gaussian. Through the strong mixing of the violent process, there appears a universal non-Gaussian velocity distribution, which is a democratic (equal-weighted) superposition of many Gaussian distributions (DT distribution). This is deeply related with the local virial equilibrium and the linear mass-temperature relation which characterize the system. We show the robustness of this distribution function against various initial conditions which leads to the violent gravitational process. The DT distribution has a positive correlation with the energy fluctuation of the system. On the other hand, the coherent motion such as the radial motion in the spherical collapse and the rotation with the angular momentum suppress the appearance of the DT distribution.

Primary care training in Kosovo.

Primary care training during and after conflicts is one of the most challenging health care issues but is often neglected compared to emergency medical care. Recently, family medicine has been increasingly used as a model strategy to reconstruct primary care delivery systems in communities torn by conflicts. The lessons learned through providing primary pediatric care training in Kosovo, in two periods, both shortly before the NATO air strike and after the war in Kosovo, are shared in this paper. The training program was organized and provided in collaboration with the Kosovar nongovernmental organization, Mother Teresa Society, and Kinderberg International in support of United Nations High Commissioner for Refugees as a pilot program. This paper provides a narrative description of training experiences that focused on practical bedside training and morale support throughout these two periods. Based on our evaluation, providing morale support at the field level to encourage the health care providers' motivation for learning and collegial support while suffering physical difficulties was beneficial. International primary care organizations should maintain collegial dialogue to support indigenization of family medicine, a process that adapts the principles of family medicine into their own needs in their communities.

Risk factors for depression in the survivors of the 1988 earthquake in Armenia.

Most studies of psychopathology following disasters are concerned with posttraumatic stress disorder (PTSD). The present analyses sought to assess the rate and determinants of depression in adult survivors of the 1988 earthquake in Armenia. Unlike previous studies of earthquakes, the present analyses derive from a well-defined cohort of survivors who underwent diagnostic interviewing to characterize psychiatric morbidity. As part of a cohort study of 32,743 survivors of the 1988 earthquake in Armenia, a stratified population sample of 1,785 persons was interviewed about 2 years following the disaster using a special questionnaire based on the National Institute of Mental Health (NIMH) Disaster Interview Schedule/Disaster Supplement. 52% met the criteria for major depression. Of these, a total of 177 cases of depression with no other psychiatric diagnosis or comorbidity were compared with 583 controls from the same interviewed group who did not fulfill the criteria for any psychiatric disorder. Cases and controls were compared as to data obtained independently at the aftermath of the disaster on a number of exposures and characteristics related to the earthquake. More of the cases involved females (odds ratio [OR] for males 0.7 [95% confidence interval [CI] 0.5-0.9]) and from the city of Gumri, which had some of the worst destruction (OR for residents of Gumri 5.9 [95% CI 4.0-8.8]). Being with someone in the same building at the moment of the earthquake was protective for depression (OR for presence of other people 0.5 [95% CI 0.3-0.6]), and the risk of depression increased with the amount of loss that the family sustained as a result of the earthquake (OR for highest level of loss 2.5 [95% CI 1.3-4.8]). The use of alcohol was protective for depression (OR for those who drink 0.5 [95% CI 0.3-0.8]). In various models of multivariate adjustment and analysis, the increased risk of depression with loss, geographic location, and female gender was maintained. Also, being with someone during the disaster, receiving assistance and support after the earthquake, and alcohol use were protective for depression in these multivariate analyses. Depression is a common sequel to an earthquake. As with our previous study of PTSD, we were able to relate intensity of the disaster and loss to the risk of depression in a general population sample. The role of social support during and after the disaster as a protective mechanism against adverse psychological outcome was highlighted again. Whereas alcohol use in our previous study was not related to PTSD outcome, it is noteworthy that in the present analyses it emerged as a protective factor for depression.