Zeros of the Jimbo, Miwa, Ueno tau function

We introduce a family of local deformations for meromorphic connections on the Riemann sphere in the neighborhood of a higher rank (simple) singularity. Following a scheme introduced by Malgrange we use these local models to prove that the zeros of the tau function introduced by Jimbo, Miwa and Ueno occur precisely at those points in the deformation space at which a certain Birkhoff-Riemann- Hilbert problem fails to have a solution.Comment: 59 page

Corporation Law: The Business Judgment Rule in Derivative Suits against Directors

Galef v. Alexander, 615 F.2d 51 (2d Cir. 1980). The shareholders derivative suit is the principal means available to minority shareholders to correct abuses committed by corporate management. Recent federal court decisions have limited the availability of this action through application of the “business judgment” rule. This rule provides corporate management with a shield to protect their actions concerning the business affairs of the corporation from judicial scrutiny. Applied to a derivative action, the rule operates as a bar to the shareholder’s suit, provided the directors seeking its application do not “stand in a dual relation that prevents an unprejudiced exercise of judgment.” Application of the business judgment rule was the crucial issue confronting the court in Galef v. Alexander. Resolution of this issue was further complicated when Galef alleged violations of both state law and the federal proxy requirements of the Securities Exchange Act of 1934. This note evaluates the Galef court’s application of the business judgment rule and the impact of the court’s decision on the policies underlying the business judgment rule, and section 14(a) of the Securities Exchange Act of 1934

Middle Convolution and Harnad Duality

We interpret the additive middle convolution operation in terms of the Harnad duality, and as an application, generalize the operation to have a multi-parameter and act on irregular singular systems.Comment: 50 pages; v2: Submitted version once revised according to referees' comment

Reducing the Stigma of Mental Illness Among Medical Students

Abstract: The American Osteopathic Association House of Delegates Resolution 205 recommends “increased awareness of depression amongst U.S. Medical students” due to the increasing body of research describing the rise of depression, burn-out and suicide ideation among medical students. There is consequently a need to understand mental health issues as a component of professional development. Hypothesis: A student-led symposium addressing mental and emotional health topics relevant to medical students would reduce the stigma associated with mental illness. Materials and Methods: A 2-hour student-run “Patient Perspective” was held during the second neuroscience block at an osteopathic medical school in the northeastern United States. One week before the program, a student-developed online Wellness Survey measured prevalence of mental illness, common feelings during medical school, coping mechanisms used for stress, and use of mental health resources. Immediately before and after the program, students were asked to report their familiarity with mental illness and their feelings regarding a vignette about a mentally ill woman using “Mental Illness Among Us” pre and post surveys provided by the University of California San Francisco School of Medicine and adapted for the event. During the program, data from the online survey were shared, student organizers discussed emotional wellness and positive coping mechanisms in the context of the profession, and student panelists shared their experiences with mental health issues. A faculty psychiatrist spoke about mental health resources, and attendees received pamphlets listing these resources. The event concluded with student-led breakout sessions at which stress during medical school and strategies for promoting positive coping mechanisms were discussed, followed by the post survey. Results: 113 students completed the pre survey, 89 of whom completed the post survey. For these 89, differences between post and pre responses were universally in the direction of increasing acceptance and decreasing stigma of those with mental illness; all differences were statistically significant. The largest shift regarded students’ reluctance to disclose their own theoretical mental illness to colleagues. Conclusion: Incorporating an emotional health symposium into medical students’ training may increase understanding and acceptance of those who may have mental illness and reduce stigma associated with mental illness.https://digitalcommons.pcom.edu/posters/1002/thumbnail.jp

Reducing the stigma of mental illness among medical students

Background: The American Osteopathic Association House of Delegates Resolution 205 recommends “increased awareness of depression amongst U.S. medical students” due to the increasing body of research describing the rise of depression, burn-out and suicide ideation among medical students. There is consequently a need to understand mental health issues as a component of professional development. Hypothesis: A student-led symposium addressing mental and emotional health topics relevant to medical students will reduce the stigma associated with mental illness. Materials and Methods: A 2-hour student-run “Patient Perspective” session was held during the second year neuroscience block in the PCOM DO program. One week before the program, a student-developed, online Wellness Survey measured prevalence of mental illness, common feelings during medical school, coping mechanisms used for stress, and use of mental health resources. Immediately before and after the program, students were asked to report their familiarity with mental illness and their feelings regarding a vignette about a mentally ill woman. Pre- and post-activity surveys were provided by the University of California San Francisco School of Medicine and adapted for the event. During the program, data from the online survey were shared, student organizers discussed emotional wellness and positive coping mechanisms in the context of the profession, and student panelists shared their experiences with mental health issues. A faculty psychiatrist spoke about mental health resources, and attendees received pamphlets listing these resources. The event concluded with student-led breakout sessions in which stress during medical school and strategies for promoting positive coping mechanisms were discussed, followed by administration of the post-activity survey. Results: 113 students completed the pre-activity survey; 89 completed the post-activity survey. For these 89, differences between responses were universally in the direction of increasing acceptance and decreasing stigma of those with mental illness; all differences were statistically significant. The largest shift regarded students’ reluctance to disclose their own theoretical mental illness to colleagues. Conclusion: Incorporating an emotional health symposium into medical students’ training may increase understanding and acceptance of those who may have mental illness and reduce stigma associated with mental illness

Culture Impacts the Neural Response to Perceiving Outgroups Among Black and White Faces

Outgroup members (e.g., individuals whose racial identity differs from perceivers’) are stigmatized in Eastern and Western cultures. However, it remains an open question how specific cultural influences affect stigmatization. In this study, we assessed whether cultural learning (i.e., social information acquired from the people in one’s environment) associated with Chinese individuals’ relocation to the United States differentiated the response to multiple outgroups. Two types of cultural learning predict diverging responses to outgroups – awareness of stereotypes about different racial outgroups is associated with increased negative affect and cognitive control toward the stereotyped outgroup. Conversely, intergroup contact attenuates those responses, and does so to a greater extent for individuals from Western cultures. As Chinese–Americans would have had more opportunities to have contact with both White and Black individuals (relative to the Chinese participants), we explored their responses to outgroups as well. Because the neural regions associated with stereotyping and intergroup contact have been well-characterized, we used neuroimaging to disentangle these possibilities. Eighteen White American, 18 Chinese–American, and 17 Chinese participants – who had relocated to the United States less than 1 year prior – viewed images of Black and White individuals while undergoing functional magnetic resonance imaging (fMRI). Participants also completed measures of awareness of cultural stereotypes in the United States about Black and White individuals, implicit bias, and experiences with White and Black individuals. Behaviorally, White American and Chinese–American participants had more intergroup contact with either race than did Chinese participants, but there was no effect of participant group on stereotype knowledge or implicit bias. When viewing faces of White (as compared to Black) individuals while undergoing fMRI, White American (relative to Chinese) participants had attenuated activation in regions of the brain associated with cognitive control, including the right dorsolateral prefrontal cortex, dorsal striatum, and ventrolateral prefrontal cortex. Chinese–Americans’ neural response to either race did not differ from White American or Chinese participants. Taken together, outgroup biases seemed to emerge in a culturally-dependent way based on variability in intergroup contact, but not necessarily awareness of stereotypes

Measurements of Excess O3, CO2, CO, CH4, C2H4, C2H2, HCN, NO, NH3, HCOOH, CH3COOH, HCHO, and CH3OH in 1997 Alaskan Biomass Burning Plumes by Airborne Fourier Transform Infrared Spectroscopy (AFTIR)

We used an airborne Fourier transform infrared spectrometer (AFTIR), coupled to a flow-through, air-sampling cell, on a King Air B-90 to make in situ trace gas measurements in isolated smoke plumes from four, large, boreal zone wildfires in interior Alaska during June 1997. AFTIR spectra acquired near the source of the smoke plumes yielded excess mixing ratios for 13 of the most common trace gases: water, carbon dioxide, carbon monoxide, methane, nitric oxide, formaldehyde, acetic acid, formic acid, methanol, ethylene, acetylene, ammonia and hydrogen cyanide. Emission ratios to carbon monoxide for formaldehyde, acetic acid, and methanol were 2.2±0.4%, 1.3±0.4%, and 1.4±0.1%, respectively. For each oxygenated organic compound, a single linear equation fits our emission factors from Alaska, North Carolina, and laboratory fires as a function of modified combustion efficiency (MCE). A linear equation for predicting the NH3/NOx emission ratio as a function of MCE fits our Alaskan AFTIR results and those from many other studies. AFTIR spectra collected in downwind smoke that had aged 2.2±1 hours in the upper, early plume yielded ΔO3/ΔCO ratios of 7.9±2.4% resulting from O3 production rates of ∼50 ppbv h−1. The ΔNH3/ΔCO ratio in another plume decreased to 1/e of its initial value in ∼2.5 hours. A set of average emission ratios and emission factors for fires in Alaskan boreal forests is derived. We estimate that the 1997 Alaskan fires emitted 46±11 Tg of CO2

Trace Gas and Particle Emissions from Fires in Large Diameter and Belowground Biomass Fuels

[1] We adopt a working definition of residual smoldering combustion (RSC) as biomass combustion that produces emissions that are not lofted by strong fire-induced convection. RSC emissions can be produced for up to several weeks after the passage of a flame front and they are mostly unaffected by flames. Fuels prone to RSC include downed logs, duff, and organic soils. Limited observations in the tropics and the boreal forest suggest that RSC is a globally significant source of emissions to the troposphere. This source was previously uncharacterized. We measured the first emission factors (EF) for RSC in a series of laboratory fires and in a wooded savanna in Zambia, Africa. We report EFRSC for both particles with diameter \u3c2.5 μm (PM2.5) and the major trace gases as measured by open-path Fourier transform infrared (OP-FTIR) spectroscopy. The major trace gases include carbon dioxide, carbon monoxide, methane, ethane, ethene, acetylene, propene, formaldehyde, methanol, acetic acid, formic acid, glycolaldehyde, phenol, furan, ammonia, and hydrogen cyanide. We show that a model used to predict trace gas EF for fires in a wide variety of aboveground fine fuels fails to predict EF for RSC. For many compounds, our EF for RSC-prone fuels from the boreal forest and wooded savanna are very different from the EF for the same compounds measured in fire convection columns above these ecosystems. We couple our newly measured EFRSC with estimates of fuel consumption by RSC to refine emission estimates for fires in the boreal forest and wooded savanna. We find some large changes in estimates of biomass fire emissions with the inclusion of RSC. For instance, the wooded savanna methane EF increases by a factor of 2.5 even when RSC accounts for only 10% of fuel consumption. This shows that many more measurements of fuel consumption and EF for RSC are needed to improve estimates of biomass burning emissions

Multi-Magnon Scattering in the Ferromagnetic XXX-Model with Inhomogeneities

We determine the transition amplitude for multi-magnon scattering induced through an inhomogeneous distribution of the coupling constant in the ferromagnetic XXX-model. The two and three particle amplitudes are explicitely calculated at small momenta. This suggests a rather plausible conjecture also for a formula of the general n-particle amplitude.Comment: 21 pages, latex, no figure

Satellite‐Based Monitoring of Irrigation Water Use: Assessing Measurement Errors and Their Implications for Agricultural Water Management Policy

Reliable accounting of agricultural water use is critical for sustainable water management. However, the majority of agricultural water use is not monitored, with limited metering of irrigation despite increasing pressure on both groundwater and surface water resources in many agricultural regions worldwide. Satellite remote sensing has been proposed as a low-cost and scalable solution to fill widespread gaps in monitoring of irrigation water use in both developed and developing countries, bypassing the technical, socioeconomic, and political challenges that to date have constrained in situ metering. In this paper, we show through a systematic meta-analysis that the relative accuracy of different satellite-based irrigation water use monitoring approaches remains poorly understood, with evidence of large uncertainties when water use estimates are validated against in situ irrigation data at both field and regional scales. Subsequently, we demonstrate that water use measurement errors result in large economic welfare losses for farmers and may negatively impact ability of policies to limit acute and nonlinear externalities of irrigation abstraction on both the environment and other water users. Our findings highlight that water resource planners must consider the trade-offs between accuracy and costs associated with different water use accounting approaches. Remote sensing has an important role to play in supporting improved agricultural water accounting—both independently and in combination with in situ monitoring. However, greater transparency and evidence is needed about underlying uncertainties in satellite-based models, along with how these measurement errors affect the performance of associated policies to manage different short- and long-term externalities of irrigation water use