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Oxidative stress is implicated in the etiology of schizophrenia, and the antioxidant defense system may be protective in this illness. We examined the major antioxidant glutathione (GSH) in prefrontal brain, and its correlates with clinical and demographic variables, in schizophrenia.
GSH levels were measured in the dorsolateral prefrontal region of 28 patients with chronic schizophrenia using a magnetic resonance spectroscopy sequence specifically adapted for GSH. We examined correlations of GSH levels with age, age at onset of illness, duration of illness, and clinical symptoms.
We found a negative correlation between GSH levels and age at onset (r=-.46, p=.015), and a trend-level positive relationship between GSH and duration of illness (r=.34, p=.076).
Our findings are consistent with a possible compensatory upregulation of the antioxidant defense system with longer duration of illness, and suggests the antioxidant defense system may play a role in schizophrenia.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
In order to pursue device applications of magnetoelectric Cr2O3, we have fabricated epitaxial Cr2O3 thin films on (001), (110) and (101) oriented Nb doped TiO2 by pulsed laser deposition. The Cr2O3 films with different thicknesses (0.3 1 ¦Ìm) showed extremely smooth surfaces with rms roughness ¡Ö 0.3 nm (for 10 X 10 ¦Ìm2) as measured by AFM for all 3 different orientations. The films display robust insulating properties at room temperature with leakage current density of 8.9 X 10-6 A/cm2 at 10 kV/cm for 300 nm thick films. In order to investigate exchange bias, we fabricated bilayer films of Cr2O3/Co with all 3 orientations. The magnetic properties of the films were measured using SQUID and the magnetic optical Kerr effect (MOKE). From the Cr2O3/Co film grown on a (110) oriented TiO2, we clearly observe exchange bias of ¡Ö 13 Oe with a coercive field of 115 Oe upon cooling from 320 K to 30 K in a 1 T magnetic field. The microstructural properties of the bilayers and the effect of electric field on the exchange bias behavior were investigated using TEM, VSM and MOKE. Comparison of exchange bias with BiFeO3 and TbMnO3 multiferroic thin films will also be discussed. This work is supported by W. M. Keck Foundation, ONR grant No. N00014-01-1-0761, N00014-04-1-0085, and the NSF under grants DMR-00-94265 (CAREER), NSF DMR-00-0231291, NSF 0095166, NSF-MRSEC Award No. DMR-00-0520471. We acknowledge use of the Nanoscale Imaging, Spectroscopy, and Properties (NISP) Laboratory for TEM characterization.
Systems engineering and design thinking have been widely seen as distinctly different processes, systems engineering being more data-driven and analytical, and design thinking being more human- centred and creative. We use the term ‘design thinking’ to encompass the plurality of human-centered design processes that seek to unpack the core values behind design decisions. With the increased awareness that both systems engineering and design thinking need each other, the effects of a possibly persisting distinction on engineers’ attitudes toward these two processes are not well understood. In this paper, we describe the development and validation of a scale for measuring individual attitudes about systems engineering and design thinking. Thematic analysis of engineering and design literature is used to derive a Likert scale reflecting these attitudes. We use exploratory and confirmatory factor analysis to test and confirm this two-factor thematic representation, resulting in a 9-item Systems Engineering and Design Thinking Scale measure of attitudes.
Populations of Critically Endangered White-rumped Gyps bengalensis and Slender-billed G. tenuirostris Vultures in Nepal declined rapidly during the 2000s, almost certainly because of the effects of the use in livestock of the non-steroidal anti-inflammatory drug diclofenac, which is nephrotoxic to Gyps vultures. In 2006, veterinary use of diclofenac was banned in Nepal and this was followed by the gradual implementation, over most of the geographical range of the two vulture species in Nepal, of a Vulture Safe Zone (VSZ) programme to advocate vulture conservation, raise awareness about diclofenac, provide vultures with NSAID-free food and encourage the veterinary use in livestock of a vulture-safe alternative NSAID (meloxicam). We report the results of long-term monitoring of vulture populations in Nepal before and after this programme was implemented, by means of road transects. Piecewise regression analysis of the count data indicated that a rapid decline of the White-rumped Vulture population from 2002 up to about 2013 gave way to a partial recovery between about 2013 and 2018. More limited data for the Slender-billed Vulture indicated that a rapid decline also gave way to partial recovery from about 2012 onwards. The rates at which populations were increasing in the 2010s exceeded the upper end of the range of increase rates expected in a closed population under optimal conditions. The possibility that immigration from India is contributing to the changes cannot be excluded. We present evidence from open and undercover pharmacy surveys that the VSZ programme had apparently become effective in reducing the availability of diclofenac in a large part of the range of these species in Nepal by about 2011. Hence, community-based advocacy and awareness-raising actions, and possibly also provisioning of safe food, may have made an important contribution to vulture conservation by augmenting the effects of changes in the regulation of toxic veterinary drugs.
Disasters can damage the essential public health infrastructure and social protection systems required for vulnerable populations. This contributes to indirect mortality and morbidity as high as 70–90%, primarily due to an exacerbation of life-threatening conditions and chronic diseases. Despite this, the traditional focus of public health systems has been on communicable diseases. To address this challenge, disaster and health planners require access to repeatable and measurable methods to rank and prioritize the needs of people with life-threatening and chronic diseases before, during, and after a disaster.
Propose a repeatable and measurable method for ranking and prioritizing the needs of people with life-threatening and chronic diseases before, during, and after a disaster.
The research began with identifying the risk disasters pose to people with life-threatening and chronic diseases. The data gathered was then used to develop indicators and explore the use of DisasterAWARE™ (All-hazard Warnings, Analysis, and Risk Evaluation) to rank and prioritize the needs before, during, and after a disaster.
This research found people at greatest risk are those with underlying cardiovascular and respiratory diseases, unstable diabetes, renal diseases, and those undergoing cancer treatment. A sustainable method to help address this problem is to expand the use of DisasterAWARE™ (All-hazard Warnings, Analysis, and Risk Evaluation) to rank and prioritize needs at national and sub-national levels.
DisasterAWARE™ has been successfully applied to the assessment and prioritization of disaster risk and humanitarian assistance needs in Southeast Asia (ASEAN, Viet Nam), Central America (Guatemala, El Salvador, Honduras, Nicaragua), South America (Peru), and the Caribbean (Jamaica, Dominican Republic). Using the indicators developed through this research, this proven methodology can be seamlessly and easily translated to rank and prioritize the needs of people with life-threatening and chronic diseases before, during, and after a disaster.
Exposure to traumatic events is surprisingly common, yet little is known about its effect on decision making beyond the fact that those with post-traumatic stress disorder are more likely to have substance-abuse problems. We examined the effects of exposure to severe trauma on decision making in low-income, urban African Americans, a group especially likely to have had such traumatic experiences.
Participants completed three decision-making tasks that assessed the subjective value of delayed monetary rewards and payments and of probabilistic rewards. Trauma-exposed cases and controls were propensity-matched on demographic measures, treatment for psychological problems, and substance dependence.
Trauma-exposed cases discounted the value of delayed rewards and delayed payments, but not probabilistic rewards, more steeply than controls. Surprisingly, given previous findings that suggested women are more affected by trauma when female and male participants’ data were analyzed separately, only the male cases showed steeper delay discounting. Compared with nonalcoholic males who were not exposed to trauma, both severe trauma and alcohol-dependence produced significantly steeper discounting of delayed rewards.
The current study shows that exposure to severe trauma selectively affects fundamental decision-making processes. Only males were affected, and effects were observed only on discounting delayed outcomes (i.e. intertemporal choice) and not on discounting probabilistic outcomes (i.e. risky choice). These findings are the first to show significant differences in the effects of trauma on men's and women's decision making, and the selectivity of these effects has potentially important implications for treatment and also provides clues as to underlying mechanisms.
The study is aimed to better understand how post-acute-care services help persons with acquired brain injury (ABI) and their families following acute-care discharge. Participants included 21 primary family caregivers of persons with ABI. Participants reported their level of satisfaction with 14 different post-acute-care ABI services following discharge from an acute-care ABI facility in a large south-western city in the United States. Participants completed a survey following the discharge (on average 8.1 months) of their family member from acute-care services. Surveys included both quantitative and open-ended questions. The present study focused on participant satisfaction ratings and perceptions of helpfulness among the 14 different service areas. The average satisfaction rating across the 14 service areas was 73.4%. Professional consultation and assessment (81.8%) received the highest satisfaction rating, followed by therapy and intervention (77.9%), and peer support (51.9%). Open-ended question responses on the helpfulness of post-acute-care services focused on (a) therapy and intervention and (b) professional consultation and assessment. Study findings highlight the need to track the use of ABI services from the acute-phase through long-term community adjustment. Findings also underscore the importance of targeting interventions and services specific to the post-acute phase of ABI rehabilitation.
The strongest lines have been measured in 73 quasar spectra from the archives of the International Ultraviolet Explorer Satellite. The optically bright quasars observed with IUE were typically discovered by powerful radio emission or ultraviolet excess. They therefore should not be biased directly by observational selection with respect to ultraviolet line strength.
The Palomar-Green Survey produced statistically complete samples of hot white dwarfs and subdwarfs, from which the local mass density of these objects can be determined. The luminosity function of hot hydrogen-atmosphere white dwarfs (DA's) was recently re-determined by Fleming, Liebert, and Green (1985, Ap. J., submitted). The contribution of each of the 353 objects to the local space density was calculated from the ensemble of limiting magnitudes and a spectroscopically or photometrically derived absolute magnitude. The local surface density of white dwarfs with MV < 12.75 (log L/L⊙ > −3.1; TE > 9000 K) is 0.32 ± 0.03 pc−2. Assuming an exponential disk with scale height 250 pc, we derive the differential luminosity function in the figure; the total volume density is 0.65 ± 0.06 per 1000 pc3. He atmosphere degenerates add another 20%.
The diagnosis of dementia remains inadequate, even within clinical settings. Data on rates and degree of impairment among inpatients are vital for service planning and the provision of appropriate patient care as Ireland's population ages.
Every patient aged 65 years and over admitted over a two-week period was invited to participate. Those who met inclusion criteria were screened for delirium then underwent cognitive screening. Demographic, functional, and outcome data were obtained from medical records, participants, and family.
Consent to participate was obtained from 68.6% of the eligible population. Data for 143 patients were obtained. Mean age 78.1 years. 27.3% met criteria for dementia and 21% had mild cognitive impairment (MCI). Only 41% of those with dementia and 10% of those with MCI had a previously documented impairment. Between-group analysis showed differences in length of stay (p = 0.003), number of readmissions in 12 months (p = 0.036), and likelihood of returning home (p = 0.039) between the dementia and normal groups. MCI outcomes were similar to the normal group. No difference was seen for one-year mortality. Effects were less pronounced on multivariate analysis but continued to show a significant effect on length of stay even after controlling for demographics, personal and family history, and anxiety and depression screening scores. Patients with dementia remained in hospital 15.3 days longer (p = 0.047). A diagnosis is the single biggest contributing factor to length of stay in our regression model.
Cognitive impairment is pervasive and under-recognized in the acute hospital and impacts negatively on patient outcomes.
The study aimed to understand the use and barriers to use of post-acute-care services by persons with acquired brain injury (ABI). A total of 21 primary family caregivers of persons recently discharged from an ABI acute-care facility in a large southwestern city in the United States participated. Service use in 14 domains appeared consistent with post-discharge needs. In five service areas, participants were not aware the service was available. Professionals in acute ABI rehabilitation units need to be fully aware of the range of available potential supports and diligent in informing injured persons and their families about available post-discharge services.
The Livingstone's fruit bat Pteropus livingstonii is endemic to the small islands of Anjouan and Mohéli in the Comoros archipelago, Indian Ocean. The species is under threat from anthropogenic pressure on the little that remains of its forest habitat, now restricted to the islands’ upper elevations and steepest slopes. We report the results of the most comprehensive survey of this species to date, and present recommendations for ongoing field conservation efforts and monitoring. Morning counts were conducted at roost sites in the wet and dry seasons during 2011–2013. Habitat structure around the roosting sites was characterized and roost numbers compared, to investigate the potential effect of habitat loss and degradation. We estimate the population to comprise c. 1,260 individuals distributed across 21 roosts on the two islands. All occupied roosting sites were restricted to a narrow altitudinal range, and roosting populations in agroforestry areas were smaller than those found in degraded and undisturbed forest. Only one of the 16 roosts on Anjouan was found in undisturbed, old-growth forest with no nearby signs of clearance for agriculture or landslides following tree-felling upslope. Following a suspected severe population decline as a result of widespread and long-term forest loss Livingstone's fruit bat has been recategorized as Critically Endangered on the IUCN Red List.
In this review, the currently published, complete, spectroscopically identified samples of quasars are assembled to produce a composite luminosity function, independent of evolutionary assumptions. Two interpretations of the change with cosmic time provide reasonable fits to the data. Luminosity evolution implies a fixed population of host objects, with nuclear luminosity that fades with advancing cosmic time; some dependence of the timescale on intrinsic luminosity is required. Density evolution traces objects of comparable luminosity to find the change in space density, without a requirement of long lifetime. The change in co-moving volume density depends on luminosity; newer data suggest that somewhat stronger evolution is required at the low luminosity end than the models of Schmidt and Green allowed. Caution is advised in drawing direct physical conclusions about the evolution of individual quasars from mathematical representations of ensemble properties.
CCD images of quasars having redshifts between 0.3 and 0.65 are analyzed to study the association of galaxies with quasars. Average luminosity functions (LF) of the excess galaxies associated with the radio-loud quasars are determined. It is found that for the sub-sample with z>0.55, there is a significant brightening of the characteristic magnitude M*, if qo is assumed to be 0. Comparing computed quasar-galaxy spatial-covariance amplitudes, we can conclude, at the 0.025 significance level, that the spatial-covariance amplitudes of the sub-sample with z>0.55 are greater than those of the lower redshift quasars. This indicates that there has been a strong evolution of preferred sites for bright radio-loud quasars, implying some number-density evolution of quasars has taken place, and that some rich clusters at z∼0.6, in comparison with the local rich clusters, have significantly different physical conditions.
Markarian 478 is the prototype narrow-line Seyfert 1 galaxy. Based on its spectra taken by the FUSE, HST/FOS, and Kitt Peak Observatory 2m Telescope, we find a tendency that the emission lines of increasing ionization level show increasing excess flux at their blue wings and an increasing line peak velocity shift. This may indicate an outflowing component in the Broad-Line Region (BLR) where the ionization level increases with ejection velocity. In the mean time, the associated absorption lines are present on the blue wings of the high-ionization emission doublet O VI λλ1032, 1038 and Lyman β line. The physical condition of some absorbing components can be well constrained with the assistance of photoionization models. The flux ratios at the blue wings of emission lines of various ionization levels, as a function of outflow velocity, could also put important constraints on the physical condition of the outflowing components.
We are investigating field galaxy evolution with the optical multiband survey of Osmer et al. (1995, in preparation; Hall et al. 1992, Bull. A.A.S., 24, 1136), which covers some 3000 sq. arcmin of sky with CCD photometry in six broad-band filters from 3000-10000Å, complete down to R∼23. The sample contains some 9000 cataloged galaxies, of which 7000 have data in at least three colors.