First Measurement of Discrimination between Helium and Electron Recoils in Liquid Xenon for Low-Mass Dark Matter Searches.

We report the first measurement of discrimination between low-energy helium recoils and electron recoils in liquid xenon. This result is relevant to proposed low-mass dark matter searches which seek to dissolve light target nuclei in the active volume of liquid-xenon time projection chambers. Low-energy helium recoils were produced by degrading α particles from ^{210}Po with a gold foil situated on the cathode of a liquid xenon time-projection chamber. The resulting population of helium recoil events is well separated from electron recoils and is also offset from the expected position of xenon nuclear recoil events.

High-frequency measurement of depressive severity in a patient treated for severe treatment-resistant depression with deep-brain stimulation.

Although there have been previous studies of deep-brain stimulation (DBS), we present, to our knowledge, the first example of high-frequency depressive severity measurement-based DBS treatment in particular and psychiatric treatment in general. Daily post-surgical e-mail prompts for a period of 6 months resulted in 93 administrations of a computerized adaptive test (CAT) of depression severity (CAT-Depression Inventory or CAT-DI) via the internet. There was an average of 3.37 weekly measurements with an average separation of 2.12 days. No additional incentive was provided to the patient for completing the adaptive tests. The patient is a 55-year-old female with six psychiatric hospitalizations for depression, two suicide attempts, marginal response to eight electroconvulsive therapy (ECT) treatments and 35 psychotropic medications. We report results after high-frequency stimulation of the superolateral branch of the medial forebrain bundle. The CAT-DI was used for daily assessments before, during and after (remotely in response to an e-mail prompt) the DBS procedure. Two follow-up Hamilton Depression Scales (HAM-Ds) were also collected. Response to treatment varied markedly, with a decrease from severe (>75) to mild (60), which is three times the size of the uncertainty level. Although the HAM-D scores decreased, they missed the more complete temporal pattern identified by CAT-DI daily monitoring. We demonstrated feasibility of daily depressive severity measurement at high levels of precision and compliance. Clinician ratings confirm the general pattern of treatment benefit, but mask the marked variability in mood and more marked periods of benefit and decline.

The effect of FES-rowing training on cardiac structure and function: pilot studies in people with spinal cord injury.

STUDY DESIGN: Two studies were conducted: Study-1 was cross-sectional; and Study-2 a longitudinal repeated measures design. OBJECTIVES: To examine the influence of functional electrical stimulation (FES) rowing training on cardiac structure and function in people with spinal cord injury (SCI). SETTING: A university sports science department and home-based FES-training. METHODS: Fourteen participants with C4-T10 SCI (American Spinal Injury Association Impairment Scale A or B) were recruited for the studies. Cardiac structure and function, and peak: oxygen uptake ([Vdot ]O2peak), power output (POpeak) and heart rate (HRpeak), were compared between two FES-untrained groups (male n=3, female n=3) and an FES-trained group (male n=3) in Study-1 and longitudinally assessed in an FES-naive group (male n=1, female n=4) in Study-2. Main outcome measures left ventricular-dimensions, volumes, mass, diastolic and systolic function, and [Vdot ]O2peak, POpeak and HRpeak. In Study-2, in addition to peak values, the [Vdot ]O2 sustainable over 30 min and the related PO and HR were also assessed. RESULTS: Sedentary participants with chronic SCI had cardiac structure and function at the lower limits of non-SCI normal ranges. Individuals with chronic SCI who habitually FES-row have cardiac structure and function that more closely resemble non-SCI populations. A programme of FES-rowing training improved cardiac structure and function in previously FES-naive people. CONCLUSION: FES-rowing training appears to be an effective stimulus for positive cardiac remodelling in people with SCI. Further work, with greater participant numbers, should investigate the impact of FES-rowing training on cardiac health in SCI. SPONSORSHIP: We thank the INSPIRE Foundation, UK, for funding these studies.

Can FES-rowing mediate bone mineral density in SCI: a pilot study.

STUDY DESIGN: A single case study. OBJECTIVES: To compare proximal tibia trabecular bone mineral density (BMD) of a participant with complete spinal cord injury (SCI), long-termed functional electrical stimulation-rowing (FES-R) trained, with previously reported SCI and non-SCI group norms. To estimate lower limb joint contact forces (JCFs) in the FES-R trained participant. SETTING: UK University and orthopaedic hospital research centre. METHODS: Bilateral proximal tibial trabecular BMD of the FES-R trained participant was measured using peripheral quantitative computerised tomography, and the data were compared with SCI and non-SCI groups. An instrumented four-channel FES-R system was used to measure the lower limb JCFs in the FES-R trained participant. RESULTS: Structurally, proximal tibial trabecular BMD was higher in the FES-R trained participant compared with the SCI group, but was less than the non-SCI group. Furthermore, left (184.7 mg cm(-3)) and right (160.7 mg cm(-3)) BMD were well above the threshold associated with non-traumatic fracture. The knee JCFs were above the threshold known to mediate BMD in SCI, but below threshold at the hip and ankle. CONCLUSION: As pathological fractures predominate in the distal femur and proximal tibia in chronic SCI patients, the fact that the FES-R trained participant's knee JCFs were above those known to partially prevent bone loss, suggests that FES-R training may provide therapeutic benefit. Although the elevated bilateral proximal tibial BMD of the FES-R participant provides circumstantial evidence of osteogenesis, this single case precludes any statement on the clinical significance. Further investigations are required involving larger numbers and additional channels of FES to increase loading at the hip and ankle.

FES-rowing in tetraplegia: a preliminary report.

STUDY DESIGN: A training intervention study using functional electrical stimulation-rowing (FES-R) in a group of eight individuals with tetraplegia. OBJECTIVES: To assess the feasibility of a structured progressive FES-R training programme in people with tetraplegia, and to explore the number and type of FES-training sessions required to enable continuous FES-R for 30 min. SETTING: A fully integrated sports centre, elite rowing training centre and university sport science department. METHODS: Eight participants with chronic complete and incomplete tetraplegia (C4 to C7, American Spinal Injury Association Impairment Scale A, B and C) who had not previously used any form of FES-assisted exercise, participated in the study. Participants completed a progressive FES-assisted training programme building to three continuous 30-min FES-R sessions per week at 60-80% of their predetermined peak power output. Thereafter, rowing performance was monitored for 12 months. MAIN OUTCOME MEASURES: number and type of FES-training sessions required before achieving 30-min continuous FES-R, and FES-R average power output (POav) pre and post 12 months training. Participant feedback of perceived benefits was also documented. RESULTS: All participants were able to continuously FES-row for 30 min after completing 13±7 FES-R training sessions. Each individual POav during 30 min FES-R increased over 12 months FES-training. FES-R was found safe and well tolerated in this group of individuals with tetraplegia. CONCLUSION: Individuals with tetraplegia are able to engage in a progressive programme of FES-R training. Future research examining FES-R training as an adjunctive therapy in people with tetraplegia is warranted.

Intra- and inter-rater reliability of jumping mechanography muscle function assessments.

Muscle function can be assessed through jumping mechanography, where portable ground reaction force plates collect dynamic information as a subject jumps. The aim of this study was to assess both intra- and inter- rater reliability of jumping mechanography. Ten healthy adults underwent 3 sets of testing (collected by 3 different raters) at two separate sessions, one week apart. They performed a number of tests in each session: multiple one-legged hopping (M1LH; on right and left legs) and single two-legged jumps (S2LJ; with or without arm swing). The S2LJ assessed variables of power per body mass, jump height, velocity and efficiency; whereas, M1LH assessed maximum force per body mass and stiffness. Inter-rater coefficients of variation (CV) were less than 0.6% and 2.6% for the S2LJ and M1LH, respectively, for the primary outcome variables of power/body mass and force/body mass. Analyzing intra-rater results also produced CVs less than 5.3% for all variables. The present study reports that the Leonardo ground reaction force plate system yields reproducible results between sessions, without significant contribution of variability from the test operator. Jumping mechanography is an easy, safe and reliable method for the assessment of lower limb musculoskeletal function.

Standardization of the Maristán Scale of Informal Care in people with schizophrenia and other psychoses.

OBJECTIVE: No instrument has been developed and validated across cultures to measure the degree of support provided by informal carers to people with schizophrenia. We aimed to develop such a measure. METHOD: The Maristán Scale of Informal Care was developed directly from the views of patients with schizophrenia in six countries. Face-to-face interviews were carried out with participants and 103 were repeated after 30 days. Principal Axis Factoring followed by Promax rotation evaluated the structure of the scale. Horn's parallel combined with bootstrapping determined the number of factors. Cronbach's alpha estimated the scale's internal consistency and intra-class correlation its test-retest reliability. RESULTS: A total of 164 interviews were undertaken, 103 with re-test. The Horn's Parallel Analysis and the analysis of the Promax rotation revealed one factor. Cronbach's alpha was 0.89. Intra-class correlation coefficient was 0.56 (95% CI 0.42-0.68) and this increased to 0.64 (95% CI 0.51-0.75) after removing two outlying values. Patients from Argentina recorded the lowest scores (poor informal support/care). CONCLUSION: The Maristán Scale of Informal Care is a reliable instrument to assess the degree of support provided by informal carers to people with schizophrenia across cultures. A confirmatory factor analysis is needed to evaluate the stability of its factor structure.

A cross-sectional study of hepatitis E virus infection in healthy people directly exposed and unexposed to pigs in a rural community in northern Thailand.

A cross-sectional study of the association between occupational pig exposure and hepatitis E virus (HEV) infection in adult pig farmers and the general population who were not directly exposed to pigs was conducted in Nan Province, Thailand, from November 2010 to April 2011. All participants were interviewed to provide information on their job history, eating habits and other potential confounders. The prevalence of anti-HEV immunoglobulin G antibodies (IgG) among 513 subjects was 23.0%. Hand washing with water and soap was associated with a lower seroprevalence of HEV infection, whereas living in an area with frequent flooding (OR 1.64, 95% CI: 1.00-2.68) and consuming internal pig organs more than twice per week (OR 3.23, 95%CI: 1.15-9.01) were both associated with a higher seroprevalence of anti-HEV IgG. There was no association between HEV seroprevalence and frequent, direct occupational pig contact.

Pollen counts and suicide rates. Association not replicated.

OBJECTIVE: To replicate a previously reported association between pollen counts and county suicide rates in the continental United States, across space and time. METHOD: The authors evaluated the relationship between airborne pollen counts and suicide rates in 42 counties of the continental United States, containing a pollen-counting station participating in the Aeroallergen Monitoring Network in the United States (N = 120,076 suicides), considering years' quarter, age group, sex, race, rural/urban location, number of local psychiatrists, and median household income, from 1999 to 2002. The county-level effects were broken into between-county and within-county. RESULTS: No within-county effects were found. Between-county effects for grass and ragweed pollen on suicide rates lost statistical significance after adjustment for median income, number of psychiatrists, and urban vs. rural location. CONCLUSION: Future research is necessary to reappraise the previously reported relationship between pollen levels and suicide rates that may have been driven by socioeconomic confounders.

Application of technetium-99m sestamibi single photon emission computed tomography in acute myocardial infarction: measuring the efficacy of therapy.

Infarct size and myocardial salvage measured by technetium (Tc)-99m sestamibi single photon emission computed tomography (SPECT) imaging have been applied as surrogate endpoints in clinical trials of acute myocardial infarction (MI). The major advantage of these endpoints over mortality is the ability to use much smaller sample sizes to compare different treatment strategies in acute MI. Multiple categories of evidence validate SPECT infarct size and myocardial salvage as surrogate endpoints, including: association with other variables used to measure infarct size; association with markers of myocardial perfusion; identification of myocardial fibrosis in pathology specimens; prediction of improvement in dysfunctional myocardial segments following revascularization; correlation between infarct size and mortality; and, demonstration that therapies which result in smaller infarct size also result in better clinical outcome in the same patients. These SPECT endpoints have been applied in over 30 clinical acute MI trials. Approximately one-third of these trials reported positive results in the intervention group or a subset of the intervention group. SPECT infarct size and myocardial salvage are the most extensively validated and widely applied surrogate endpoints in the setting of acute MI.

Risk factors for Japanese encephalitis: a case-control study.

Japanese encephalitis (JE) has been found to be endemic in Bali, Indonesia. A case-control study was conducted to identify factors associated with JE infection. All 94 serologically confirmed JE cases (cases) and 163 cases of encephalitis or aseptic meningitis without JE (controls) identified in Bali during 2001-2004 were included in the study. Potential risk factors were surveyed at hospital admission. Univariate analyses revealed the following factors to be associated with JE: older age, referral from sub-district health centre or private hospital, playing outdoors after dinner, use of mosquito repellent or spraying, proximity of the residence to rice fields, and pig ownership by the family or next-door neighbours. Multivariate analysis identified proximity to rice fields (OR 2.93, 95% CI 1.57-5.45), pig ownership (OR 2.24, 95% CI 1.17-4.26), and older age (OR 1.21, 95% CI 1.09-1.33) as being independently associated with the risk of JE. Because rice cultivation and pig rearing are essential to the economy of Bali, JE immunization is the best intervention for prevention of JE in Bali.

Predictors of length of stay following colorectal resection for neoplasms in 183 Veterans Affairs patients.

BACKGROUND: There is increasing pressure to reduce the length of stay in hospital (LOS) after colorectal surgery. The aim of this study was to identify factors that prolong LOS after colorectal surgery in a population of veterans. METHODS: Retrospective analysis was performed of all patients undergoing colorectal resection for a neoplasm at a single Veterans Affairs (VA) hospital (2002-2007). Data collected included demographics, co-morbidities, operative management, postoperative morbidity and mortality, nutritional status, and LOS. Statistical analysis included descriptive statistics, univariate analysis, and multivariate analysis. RESULTS: A total of 186 patients were identified. Three patients had an LOS of more than 100 days and were omitted from the analysis. The median LOS was 8 days. Multivariate analysis showed only two variables: coronary artery disease (CAD) and postoperative complications were predictive of prolonged LOS. Chronic obstructive pulmonary disease (COPD) was the only preoperative morbidity predictive of complications. CONCLUSIONS: The aim of this study was to identify factors that prolong LOS after colorectal surgery in a VA population. We found that CAD and postoperative complications were the only variables predictive of prolonged LOS after colorectal resection, and COPD was the only factor predictive of postoperative complications.

Low-dose nesiritide in human anterior myocardial infarction suppresses aldosterone and preserves ventricular function and structure: a proof of concept study.

BACKGROUND: B-type natriuretic peptide (BNP, nesiritide) has anti-fibrotic, anti-hypertrophic, anti-inflammatory, vasodilating, lusitropic and aldosterone-inhibiting properties but conventional doses of BNP cause hypotension, limiting its use in heart failure. OBJECTIVE: To determine whether infusion of low-dose BNP within 24 h of successful reperfusion for anterior acute myocardial infarction (AMI) would prevent adverse left ventricular (LV) remodelling and suppress aldosterone. METHODS: A translational proof-of-concept study was carried out to determine tolerability and biological activity of intravenous BNP at 0.003 and 0.006 microg/kg/min, without bolus started within 24 h of successful reperfusion for anterior AMI. 24 patients with first anterior wall ST elevation AMI and successful revascularisation were randomly assigned to receive 0.003 (n = 12) or 0.006 (n = 12) microg/kg/min of IV BNP for 72 h in addition to standard care during hospitalisation for anterior AMI. RESULTS: Baseline characteristics, drugs and peak cardiac biomarkers for myocardial damage were similar between both groups. Infusion of BNP at 0.006 microg/kg/min resulted in greater biological activity than infusion at 0.003 microg/kg/min as measured by higher mean (SEM) plasma cGMP levels (8.6 (1) vs 5.5 (1) pmol/ml, p<0.05) and suppression of plasma aldosterone (8.0 (2) to 4.6 (1) ng/dl, p<0.05), which was not seen in the 0.003 microg/kg/min group. LV ejection fraction (LVEF) improved significantly from baseline to 1 month (40 (4)% to 54 (5)%, p<0.05) in the 0.006 group but not in the 0.003 group. Infusion of BNP at 0.006 microg/kg/min was associated with a decrease of LV end-systolic volume index (61 (9) to 43 (8) ml/m(2), p<0.05) at 1 month, which was not seen in the 0.003 group. No drug-related serious adverse events occurred in either group. CONCLUSIONS: 72 h infusion of low BNP at the time of anterior AMI is well tolerated and biologically active. Patients treated with low-dose BNP had improved LVEF and smaller LV end-systolic volume at 1 month.

Design and characterization of thin multiple aperture infrared cameras.

We describe a multiple-aperture long-wave infrared camera built on an uncooled microbolometer array with the objective of decreasing camera thickness. The 5 mm thick optical system is an f/1.2 design with a 6.15 mm effective focal length. An integrated image is formed from the subapertures using correlation-based registration and a least gradient reconstruction algorithm. We measure a 131 mK NETD. The system's spatial frequency is analyzed with 4 bar targets. With proper calibration, our multichannel interpolation results recover contrast for targets at frequencies beyond the aliasing limit of the individual subimages.

Detection of myocardial infarction by dual-source coronary computed tomography angiography using quantitated myocardial scintigraphy as the reference standard.

BACKGROUND: Dual-source coronary computed tomography angiography (DS-CTA) has the potential to assess both coronary anatomy and myocardial perfusion. We studied the ability of DS-CTA to detect myocardial infarction (MI) compared to a reference standard of technetium Tc(99)m sestamibi single photon emission computed tomography (SPECT). METHODS: 122 patients with suspected or known coronary artery disease (age 60 (SD 11) years, 36% females) were evaluated by both DS-CTA and SPECT. SPECT-MI size was quantitated using a threshold value of 60% of peak counts on the resting images. MI on DS-CTA was defined as transmural or subendocardial hypoenhancement (<50% of surrounding myocardium), which persisted in both diastolic and systolic reconstructions and was concordant with a coronary artery territory. The performance of DS-CTA to detect SPECT-MI was determined in a blinded, vessel-based analysis. RESULTS: 366 vessel territories were analysed (122 patients x3). SPECT revealed 20 vessel territories with MI (involving 17 patients). 15/20 (75%) of these vessel territories were also detected by DS-CTA. An additional seven MIs were detected by DS CTA only (considered as false positive). Thus, the sensitivity of DS-CTA for detection of SPECT-MI was 75% (95% CI 56% to 94%), specificity 98% (97% to 100%), positive predictive value 68% (49% to 88%) and negative predictive value 99% (97% to 100%). DS-CTA detected 10/11 (91%) larger MIs (involving >5% of left ventricular (LV) mass by SPECT). For the 15 concordant MIs (in both SPECT and DS-CTA) the mean difference in MI size between modalities was 0.5% (4.6%) of LV mass (95% CI -8.6% to 9.5%). CONCLUSIONS: DS-CTA myocardial perfusion imaging showed moderate sensitivity and positive predictive value but high specificity and negative predictive value for detection of SPECT-MI. Most large infarcts (>5% of LV mass) were detected by DS-CTA. When MI was detected by both modalities, there was a good correlation between infarct sizes quantitated by DS-CTA vs SPECT.

The structure of lifetime manic-hypomanic spectrum.

BACKGROUND: The observation that bipolar disorders frequently go unrecognized has prompted the development of screening instruments designed to improve the identification of bipolarity in clinical and non-clinical samples. Starting from a lifetime approach, researchers of the Spectrum Project developed the Mood Spectrum Self-Report (MOODS-SR) that assesses threshold-level manifestations of unipolar and bipolar mood psychopathology, but also atypical symptoms, behavioral traits and temperamental features. The aim of the present study is to examine the structure of mania/hypomania using 68 items of the MOODS-SR that explore cognitive, mood and energy/activity features associated with mania/hypomania. METHODS: A data pool of 617 patients with bipolar disorders, recruited at Pittsburgh and Pisa, Italy was used for this purpose. Classical exploratory factor analysis, based on a tetrachoric matrix, was carried out on the 68 items, followed by an Item Response Theory (IRT)-based factor analytic approach. RESULTS: Nine factors were initially identified, that include Psychomotor Activation, Creativity, Mixed Instability, Sociability/Extraversion, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Inflated Self-esteem, Euphoria, Wastefulness/Recklessness, and account overall for 56.4% of the variance of items. In a subsequent IRT-based bi-factor analysis, only five of them (Psychomotor Activation, Mixed Instability, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Euphoria) were retained. CONCLUSIONS: Our data confirm the central role of Psychomotor Activation in mania/hypomania and support the definitions of pure manic (Psychomotor Activation and Euphoria) and mixed manic (Mixed Instability and Mixed Irritability) components, bearing the opportunity to identify patients with specific profiles for a better clinical and neurobiological definition.

Molecular analysis of isolates from influenza B outbreaks in the U.S. and Nepal, 2005.

Currently circulating influenza B viruses can be divided into two antigenically and genetically distinct lineages referred to by their respective prototype strains, B/Yamagata/16/88 and B/Victoria/2/87, based on amino acid differences in the hemagglutinin surface glycoprotein. During May and July 2005, clinical specimens from two early season influenza B outbreaks in Arizona and southeastern Nepal were subjected to antigenic (hemagglutinin inhibition) and nucleotide sequence analysis of hemagglutinin (HA1), neuraminidase (NA), and NB genes. All isolates exhibited little reactivity with the B/Shanghai/361/2002 (B/Yamagata-like) vaccine strain and significantly reduced reactivity with the previous 2003/04 B/Hong Kong/330/2001 (B/Victoria-like) vaccine strain. The majority of isolates were antigenically similar to B/Hawaii/33/2004, a B/Victoria-like reference strain. Sequence analysis indicated that 33 of 34 isolates contained B/Victoria-like HA and B/Yamagata-like NA and NB proteins. Thus, these outbreak isolates are both antigenically and genetically distinct from the current Northern Hemisphere vaccine virus strain as well as the previous 2003-04 B/Hong Kong/330/2001 (B/Victoria lineage) vaccine virus strain but are genetically similar to B/Malaysia/2506/2004, the vaccine strain proposed for the coming seasons in the Northern and Southern Hemispheres. Since these influenza B outbreaks occurred in two very distant geographical locations, these viruses may continue to circulate during the 2006 season, underscoring the importance of rapid molecular monitoring of HA, NA and NB for drift and reassortment.

Long gamma-ray bursts and core-collapse supernovae have different environments.

When massive stars exhaust their fuel, they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an even more brilliant relativistic explosion known as a long-duration gamma-ray burst. One would then expect that these long gamma-ray bursts and core-collapse supernovae should be found in similar galactic environments. Here we show that this expectation is wrong. We find that the gamma-ray bursts are far more concentrated in the very brightest regions of their host galaxies than are the core-collapse supernovae. Furthermore, the host galaxies of the long gamma-ray bursts are significantly fainter and more irregular than the hosts of the core-collapse supernovae. Together these results suggest that long-duration gamma-ray bursts are associated with the most extremely massive stars and may be restricted to galaxies of limited chemical evolution. Our results directly imply that long gamma-ray bursts are relatively rare in galaxies such as our own Milky Way.

Understanding alpha-globin gene regulation: Aiming to improve the management of thalassemia.

Over the past 50 years, many advances in our understanding of the general principles controlling gene expression during hematopoiesis have come from studying the synthesis of hemoglobin. Discovering how the alpha- and beta-globin genes are normally regulated and documenting the effects of inherited mutations that cause thalassemia have played a major role in establishing our current understanding of how genes are switched on or off in hematopoietic cells. Previously, nearly all mutations causing thalassemia have been found in or around the globin loci, but rare inherited and acquired trans-acting mutations are being found more often. Such mutations have demonstrated new mechanisms underlying human genetic disease. Furthermore, they are revealing new pathways in the regulation of globin gene expression that, in turn, may open up new avenues for improving the management of patients with common types of thalassemia.