Isospectrality and Heat Content

We present examples of isospectral operators that do not have the same heat content. Several of these examples are planar polygons that are isospectral for the Laplace operator with Dirichlet boundary conditions. These include examples with infinitely many components. Other planar examples have mixed Dirichlet and Neumann boundary conditions. We also consider Schrodinger operators acting in L-2[0,1] with Dirichlet boundary conditions, and show that an abundance of isospectral deformations do not preserve the heat content.

Spirocyclic Acylphloroglucinol Derivatives from Hypericum pyramidatum

Five spirocyclic acylphloroglucinol derivatives (1-5) have been isolated from a hexanes extract of the leaves of Hypericum pyramidatum. Pyramidatones A-D (1-3, 5) are new, and chipericumin C (4) has been previously reported. The acylphloroglucinols were characterized based on spectroscopic (NMR, IR, UV-VIS) and mass spectrometric data.

Impact of Lifetime Alcohol Use on Liver Fibrosis in a Population of HIV-Infected Patients With and Without Hepatitis C Coinfection

BACKGROUND: The effect of alcohol on liver disease in HIV infection has not been well characterized. METHODS: We performed a cross-sectional multivariable analysis of the association between lifetime alcohol use and liver fibrosis in a longitudinal cohort of HIV-infected patients with alcohol problems. Liver fibrosis was estimated with 2 noninvasive indices, "FIB-4," which includes platelets, liver enzymes, and age; and aspartate aminotransferase/platelet ratio index ("APRI"), which includes platelets and liver enzymes. FIB-4 <1.45 and APRI <0.5 defined the absence of liver fibrosis. FIB-4 >3.25 and APRI >1.5 defined advanced liver fibrosis. The main independent variable was lifetime alcohol consumption (<150 kg, 150 to 600 kg, >600 kg). RESULTS: Subjects (n = 308) were 73% men, mean age 43 years, 49% with hepatitis C virus (HCV) infection, 60% on antiretroviral therapy, 49% with an HIV RNA load <1,000 copies/ml, and 18.7% with a CD4 count <200 cells/mm(3) . Forty-five percent had lifetime alcohol consumption >600 kg, 32.7% 150 to 600 kg, and 22.3% <150 kg; 33% had current heavy alcohol use, and 69% had >9 years of heavy episodic drinking. Sixty-one percent had absence of liver fibrosis and 10% had advanced liver fibrosis based on FIB-4. In logistic regression analyses, controlling for age, gender, HCV infection, and CD4 count, no association was detected between lifetime alcohol consumption and the absence of liver fibrosis (FIB-4 <1.45) (adjusted odds ratio [AOR] = 1.12 [95% CI: 0.25 to 2.52] for 150 to 600 kg vs. <150 kg; AOR = 1.11 [95% CI: 0.52 to 2.36] for >600 kg vs. <150 kg; global p = 0.95). Additionally, no association was detected between lifetime alcohol use and advanced liver fibrosis (FIB-4 >3.25). Results were similar using APRI, and among those with and without HCV infection. CONCLUSIONS: In this cohort of HIV-infected patients with alcohol problems, we found no significant association between lifetime alcohol consumption and the absence of liver fibrosis or the presence of advanced liver fibrosis, suggesting that alcohol may be less important than other known factors that promote liver fibrosis in this population.

Panel 9: Aftereffects and Memory of the Holocaust

Panel 9: Aftereffects and Memory of the Holocaust Stefanie Rauch, University of Leicester, United Kingdom: “British Responses to the Film ‘The Boy in the Striped Pajamas’” Download paper (login required) Emily Stiles, University of Winchester, United Kingdom: "The Evil They Helped to Defeat: Exhibiting the Holocaust in Britain's National Museum of Modern Conflict" Download paper (login required) Kara Critchell, University of Winchester, United Kingdom: “The Heart of Holocaust Education: Holocaust Survivors and the Construction of Holocaust Consciousness in Britain" Download paper (login required) Noemi Staszewski, University of Frankfurt, Germany: "The Drama of Getting Dependent on Assistance in the Shadow of the Shoah: Working Experiences with Old Age Survivors in Germany " Download paper (login required) Chair: Emily Dabney and James Burnham Sedgwick, Clark UniversityComment: Marianne Hirsch, Columbia University

Men at risk The Physical, Mental and Social Health of Men in Massachusetts

In 2009, Clark University was accepted as the university to represent Massachusetts in the National Policy Institute for Family Impact Seminars at the University of Wisconsin – Madison (http://familyimpactseminars.org). Family Impact Seminars are a series of annual seminars, briefing reports, and discussion sessions that provide up-to-date, solution-oriented research on current issues for state legislators, their aides, and legislative support bureau personnel. The seminars provide objective, nonpartisan research on current issues and do not lobby for particular policies. Seminar participants discuss policy options and identify common ground where it exists.

Vulvovaginal-swab or first-catch urine specimen to detect Chlamydia trachomatis in women in a community setting?

Screening for chlamydia in women is widely recommended. We evaluated the performance of two nucleic acid amplification tests for detecting Chlamydia trachomatis in self-collected vulvovaginal-swab and first-catch urine specimens from women in a community setting and a strategy for optimizing the sensitivity of an amplified enzyme immunoassay on vulvovaginal-swab specimens. We tested 2,745 paired vulvovaginal-swab and urine specimens by PCR (Roche Cobas) or strand displacement amplification (SDA; Becton Dickinson). There were 146 women infected with chlamydia. The assays detected 97.3% (95% confidence interval [CI], 93.1 to 99.2%) of infected patients with vulvovaginal-swab specimens and 91.8% (86.1 to 95.7%) with urine specimens. We tested 2,749 vulvovaginal-swab specimens with both a nucleic acid amplification test and a polymer conjugate-enhanced enzyme immunoassay with negative-gray-zone testing. The relative sensitivities obtained after retesting specimens in the negative gray zone were 74.3% (95% CI, 62.8 to 83.8%) with PCR and 58.3% (95% CI, 46.1 to 69.8%) with SDA. In community settings, both vulvovaginal-swab and first-catch urine specimens from women are suitable substrates for nucleic acid amplification tests, but enzyme immunoassays, even after negative-gray-zone testing, should not be used in screening programs.

Epidemiological, social, diagnostic and economic evaluation of population screening for genital chlamydial infection

OBJECTIVES: To investigate epidemiological, social, diagnostic and economic aspects of chlamydia screening in non-genitourinary medicine settings. METHODS: Linked studies around a cross-sectional population-based survey of adult men and women invited to collect urine and (for women) vulvovaginal swab specimens at home and mail these to a laboratory for testing for Chlamydia trachomatis. Specimens were used in laboratory evaluations of an amplified enzyme immunoassay (PCE EIA) and two nucleic acid amplification tests [Cobas polymerase chain reaction (PCR), Becton Dickinson strand displacement amplification (SDA)]. Chlamydia-positive cases and two negative controls completed a risk factor questionnaire. Chlamydia-positive cases were invited into a randomised controlled trial of partner notification strategies. Samples of individuals testing negative completed psychological questionnaires before and after screening. In-depth interviews were conducted at all stages of screening. Chlamydia transmission and cost-effectiveness of screening were investigated in a transmission dynamic model. SETTING AND PARTICIPANTS: General population in the Bristol and Birmingham areas of England. In total, 19,773 women and men aged 16-39 years were randomly selected from 27 general practice lists. RESULTS: Screening invitations reached 73% (14,382/19,773). Uptake (4731 participants), weighted for sampling, was 39.5% (95% CI 37.7, 40.8%) in women and 29.5% (95% CI 28.0, 31.0%) in men aged 16-39 years. Chlamydia prevalence (219 positive results) in 16-24 year olds was 6.2% (95% CI 4.9, 7.8%) in women and 5.3% (95% CI 4.4, 6.3%) in men. The case-control study did not identify any additional factors that would help target screening. Screening did not adversely affect anxiety, depression or self-esteem. Participants welcomed the convenience and privacy of home-sampling. The relative sensitivity of PCR on male urine specimens was 100% (95% CI 89.1, 100%). The combined relative sensitivities of PCR and SDA using female urine and vulvovaginal swabs were 91.8% (86.1, 95.7, 134/146) and 97.3% (93.1, 99.2%, 142/146). A total of 140 people (74% of eligible) participated in the randomised trial. Compared with referral to a genitourinary medicine clinic, partner notification by practice nurses resulted in 12.4% (95% CI -3.7, 28.6%) more patients with at least one partner treated and 22.0% (95% CI 6.1, 37.8%) more patients with all partners treated. The health service and patients costs (2005 prices) of home-based postal chlamydia screening were 21.47 pounds (95% CI 19.91 pounds, 25.99) per screening invitation and 28.56 pounds (95% CI 22.10 pounds, 30.43) per accepted offer. Preliminary modelling found an incremental cost-effectiveness ratio (2003 prices) comparing screening men and women annually to no screening in the base case of 27,000 pounds/major outcome averted at 8 years. If estimated screening uptake and pelvic inflammatory disease incidence were increased, the cost-effectiveness ratio fell to 3700 pounds/major outcome averted. CONCLUSIONS: Proactive screening for chlamydia in women and men using home-collected specimens was feasible and acceptable. Chlamydia prevalence rates in men and women in the general population are similar. Nucleic acid amplification tests can be used on first-catch urine specimens and vulvovaginal swabs. The administrative costs of proactive screening were similar to those for opportunistic screening. Using empirical estimates of screening uptake and incidence of complications, screening was not cost-effective.

Psychologic factors are related to some sensory pain thresholds but not nociceptive flexion reflex threshold in chronic whiplash

OBJECTIVES: Sensory hypersensitivity, central hyperexcitability [lowered nociceptive flexion reflex (NFR) thresholds], and psychologic distress are features of chronic whiplash. However, relationships between these substrates are not clear. This study tested the hypothesis that psychologic distress and catastrophization are correlated with sensory hypersensitivity and NFR responses in chronic whiplash. METHODS: Pressure and thermal pain thresholds (mean values across 3 body sites), NFR threshold, and pain at threshold Visual Analog Scale were measured in 30 participants with chronic whiplash and 30 asymptomatic controls. Pain and disability levels Neck Disability Index, psychologic distress (GHQ-28), and catastrophization (PCS) were also measured in the whiplash group. RESULTS: Whiplash injured participants demonstrated lowered pain thresholds to pressure and cold (P<0.05); lowered NFR thresholds (P=0.003), and demonstrated above threshold levels of psychologic distress (GHQ-28) and levels of catastrophization comparable with other musculoskeletal conditions. There were no group differences for heat pain thresholds or pain at NFR threshold. In the whiplash group, PCS scores correlated moderately with cold pain threshold (r=0.51, P=0.01). In contrast, there were no significant correlations between GHQ-28 scores and pain threshold measures or between psychologic factors and NFR responses in whiplash participants. There were no significant correlations between psychologic factors and pain thresholds or NFR responses in controls. DISCUSSION: We have demonstrated that psychologic factors have some association with sensory hypersensitivity (cold pain threshold measures) in chronic whiplash but do not seem to influence spinal cord excitability. This suggests that psychologic disorders are important, but not the only, determinants of central hypersensitivity in whiplash patients.

Electron transport in E x B devices

A Hall thruster, an E × B device used for in-space propulsion, utilizes an axial electric field to electrostatically accelerate plasma propellant from the spacecraft. The axial electric field is created by positively biasing the anode so that the positivelycharged ions may be accelerated (repelled) from the thruster, which produces thrust. However, plasma electrons are much smaller than ions and may be accelerated much more quickly toward the anode; if electrons were not impeded, a "short circuit" due to the electron flow would eliminate the thrust mechanism. Therefore, a magnetic field serves to "magnetize" plasma electrons internal to the thruster and confines them in gyro-orbits within the discharge channel. Without outside factors electrons would be confined indefinitely; however, electron-neutral collisions provide a mechanism to free electrons from their orbits allowing electrons to cross the magnetic field toward the anode, where this process is described by classical transport theory. To make matters worse, cross-field electron transport has been observed to be 100-1000 times that predicted by classical collisional theory, providing an efficiency loss mechanism and an obstacle for modeling and simulations in Hall thrusters. The main difficulty in studying electron transport in Hall thrusters is the coupling that exists between the plasma and the fields, where the plasma creates and yet is influenced by the electric field. A device has been constructed at MTU’s Isp Lab, the Hall Electron Mobility Gage, which was designed specifically to study electron transport in E × B devices, where the coupling between the plasma and electric field was virtually eliminated. In this device the two most cited contributors to electron transport in Hall thrusters, fluctuation-induced transport, and wall effects, were absent. Removing the dielectric walls and plasma fluctuations, while maintaining the field environment in vacuum, has allowed the study of electron dynamics in Hall thruster fields where the electrons behave as test particles in prescribed fields, greatly simplifying the environment. Therefore, it was possible to observe any effects on transport not linked to the cited mechanisms, and it was possible to observe trends of the enhanced mobility with control parameters of electric and magnetic fields and neutral density– parameters that are not independently variable in a Hall thruster. The result of the investigation was the observation of electron transport that was ~ 20-100 times the classical prediction. The cross-field electron transport in the Mobility Gage was generally lower than that found in a Hall thruster so these findings do not negate the possibility of fluctuations and/or wall collisions contributing to transport in a Hall thruster. However, this research led to the observation of enhanced cross-field transport that had not been previously isolated in Hall thruster fields, which is not reliant on momentum-transfer collisions, wall collisions or fluctuations.

Clean water in the classroom : understanding the importance of water quality

This study’s objective was to answer three research questions related to students’ knowledge and attitudes about water quality and availability issues. It is important to understand what knowledge students have about environmental problems such as these, because today’s students will become the problem solvers of the future. If environmental problems, such as those related to water quality, are ever going to be solved, students must be environmentally literate. Several methods of data collection were used. Surveys were given to both Bolivian and Jackson High School students in order to comparison their initial knowledge and attitudes about water quality issues. To study the effects of instruction, a unit of instruction about water quality issues was then taught to the Jackson High School students to see what impact it would have on their knowledge. In addition, the learning of two different groups of Jackson High School students was compared—one group of general education students and a second group of students that were learning in an inclusion classroom and included special education students and struggling learners form the general education population. Student and teacher journals, a unit test, and postsurvey responses were included in the data set. Results suggested that when comparing Bolivian students and Jackson High School students, Jackson High School students were more knowledgeable concerning clean water infrastructure and its importance, despite the fact that these issues were less relevant to their lives than for their Bolivian counterparts. Although overall, the data suggested that all the Jackson High students showed evidence that the instruction impacted their knowledge, the advanced Biology students appeared to show stronger gains than their peers in an inclusion classroom.