3,496 research outputs found
EPICOG-SCH: A brief battery to screen cognitive impact of schizophrenia in stable outpatients
Brief batteries in schizophrenia, are needed to screen for the cognitive impact of schizophrenia. We aimed to validate and co-norm the Epidemiological Study of Cognitive Impairment in Schizophrenia (EPICOG-SCH) derived brief cognitive battery. A cross-sectional outpatient evaluation was conducted of six-hundred-seventy-two patients recruited from 234 centers. The brief battery included well-known subtests available worldwide that cover cognitive domains related to functional outcomes: WAIS-III-Letter-Number-Sequencing-LNS, Category Fluency Test-CFT, Logical-Memory Immediate Recall-LM, and Digit-Symbol-Coding-DSC. CGI-SCH Severity and WHO-DAS-S were used to assess clinical severity and functional impairment, respectively. Unit Composite Score (UCS) and functional regression-weighted Composite Scores (FWCS) were obtained; discriminant properties of FWCS to identify patients with different levels of functional disability were analyzed using receiver-operating characteristic (ROC) technique. The battery showed good internal consistency, Cronbach's alpha = 0.78. The differences between cognitive performance across CGI-SCH severity level subscales ranged from 0.5 to 1 SD. Discriminant capacity of the battery in identifying patients with up to moderate disability levels showed fair discriminant accuracy with areas under the curve (AUC) > 0.70, p < 0.0001. An FWCS mean cut-off score ≥ 100 showed likelihood ratios (LR) up to 4.7, with an LR+ of 2.3 and a LR− of 0.5. An FWCS cut-off ≥ 96 provided the best balance between sensitivity (0.74) and specificity (0.62).
The EPICOG-SCH proved to be a useful brief tool to screen for the cognitive impact of schizophrenia, and its regression-weighted Composite Score was an efficient complement to clinical interviews for confirming patients' potential functional outcomes and can be useful for monitoring cognition during routine outpatient follow-up visits
Quantum State Disturbance vs. Information Gain: Uncertainty Relations for Quantum Information
When an observer wants to identify a quantum state, which is known to be one
of a given set of non-orthogonal states, the act of observation causes a
disturbance to that state. We investigate the tradeoff between the information
gain and that disturbance. This issue has important applications in quantum
cryptography. The optimal detection method, for a given tolerated disturbance,
is explicitly found in the case of two equiprobable non-orthogonal pure states.Comment: 20 pages, standard LaTeX, four png figures (also available from the
authors: [email protected] and [email protected]
Zero Frequency Current Noise for the Double Tunnel Junction Coulomb Blockade
We compute the zero frequency current noise numerically and in several limits
analytically for the coulomb blockade problem consisting of two tunnel
junctions connected in series. At low temperatures over a wide range of
voltages, capacitances, and resistances it is shown that the noise measures the
variance in the number of electrons in the region between the two tunnel
junctions. The average current, on the other hand, only measures the mean
number of electrons. Thus, the noise provides additional information about
transport in these devices which is not available from measuring the current
alone.Comment: 33 pages, 10 figure
Quantum fields during black hole formation: how good an approximation is the Unruh state?
We study the quantum effects of a test Klein-Gordon field in a Vaidya space-time consisting of a collapsing null shell that forms a Schwazschild black hole, by explicitly obtaining, in a (1 + 1)-dimensional model, the Wightman function, the renormalised stress-energy tensor, and by analysing particle detector rates along stationary orbits in the exterior black hole region, and make a comparison with the folklore that the Unruh state is the state that emerges from black hole formation. In the causal future of the shell, we find a negative ingoing flux at the horizon that agrees precisely with the Unruh state calculation, and is the source of black hole radiation, while in the future null infinity we find that the radiation flux output in the Unruh state is an upper bound for the positive outgoing flux in the collapsing null shell spacetime. This indicates that back-reaction estimates based on Unruh state calculations over-estimate the energy output carried by so-called pre-Hawking radiation. The value of the output predicted by the Unruh state is however approached exponentially fast. Finally, we find that at late times, stationary observers in the exterior black hole region in the collapsing shell spacetime detect the local Hawking temperature, which is also well characterised by the Unruh state, coming from right-movers. Early-time discrepancies between the detector rates for the Unruh state and for the state in the collapsing shell spacetime are explored numerically
Obesity Is Not Associated with Antimicrobial Treatment Failure for Intra-Abdominal Infection
Background: Obesity and commonly associated comorbidities are known risk factors for the development of infections. However, the intensity and duration of antimicrobial treatment are rarely conditioned on body mass index (BMI). In particular, the influence of obesity on failure of antimicrobial treatment for intra-abdominal infection (IAI) remains unknown. We hypothesized that obesity is associated with recurrent infectious complications in patients treated for IAI. Methods: Five hundred eighteen patients randomized to treatment in the Surgical Infection Society Study to Optimize Peritoneal Infection Therapy (STOP-IT) trial were evaluated. Patients were stratified by obese (BMI ≥30) versus non-obese (BMI≥30) status. Descriptive comparisons were performed using Chi-square test, Fisher exact test, or Wilcoxon rank-sum tests as appropriate. Multivariable logistic regression using a priori selected variables was performed to assess the independent association between obesity and treatment failure in patients with IAI. Results: Overall, 198 (38.3%) of patients were obese (BMI ≥30) versus 319 (61.7%) who were non-obese. Mean antibiotic d and total hospital d were similar between both groups. Unadjusted outcomes of surgical site infection (9.1% vs. 6.9%, p?=?0.36), recurrent intra-abdominal infection (16.2% vs. 13.8, p?=?0.46), death (1.0% vs. 0.9%, p?=?1.0), and a composite of all complications (25.3% vs. 19.8%, p?=?0.14) were also similar between both groups. After controlling for appropriate demographics, comorbidities, severity of illness, treatment group, and duration of antimicrobial therapy, obesity was not independently associated with treatment failure (c-statistic: 0.64). Conclusions: Obesity is not associated with antimicrobial treatment failure among patients with IAI. These results suggest that obesity may not independently influence the need for longer duration of antimicrobial therapy in treatment of IAI versus non-obese patients.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140219/1/sur.2015.213.pd
Hypothesis Article Signatures of a Shadow Biosphere
Abstract Astrobiologists are aware that extraterrestrial life might differ from known life, and considerable thought has been given to possible signatures associated with weird forms of life on other planets. So far, however, very little attention has been paid to the possibility that our own planet might also host communities of weird life. If life arises readily in Earth-like conditions, as many astrobiologists contend, then it may well have formed many times on Earth itself, which raises the question whether one or more shadow biospheres have existed in the past or still exist today. In this paper, we discuss possible signatures of weird life and outline some simple strategies for seeking evidence of a shadow biosphere
Increased mortality in community-tested cases of SARS-CoV-2 lineage B.1.1.7.
SARS-CoV-2 lineage B.1.1.7, a variant that was first detected in the UK in September 20201, has spread to multiple countries worldwide. Several studies have established that B.1.1.7 is more transmissible than pre-existing variants, but have not identified whether it leads to any change in disease severity2. Here we analyse a dataset that links 2,245,263 positive SARS-CoV-2 community tests and 17,452 deaths associated with COVID-19 in England from 1 November 2020 to 14 February 2021. For 1,146,534 (51%) of these tests, the presence or absence of B.1.1.7 can be identified because mutations in this lineage prevent PCR amplification of the spike (S) gene target (known as S gene target failure (SGTF)1). On the basis of 4,945 deaths with known SGTF status, we estimate that the hazard of death associated with SGTF is 55% (95% confidence interval, 39-72%) higher than in cases without SGTF after adjustment for age, sex, ethnicity, deprivation, residence in a care home, the local authority of residence and test date. This corresponds to the absolute risk of death for a 55-69-year-old man increasing from 0.6% to 0.9% (95% confidence interval, 0.8-1.0%) within 28 days of a positive test in the community. Correcting for misclassification of SGTF and missingness in SGTF status, we estimate that the hazard of death associated with B.1.1.7 is 61% (42-82%) higher than with pre-existing variants. Our analysis suggests that B.1.1.7 is not only more transmissible than pre-existing SARS-CoV-2 variants, but may also cause more severe illness
Increased hazard of death in community-tested cases of SARS-CoV-2 Variant of Concern 202012/01.
VOC 202012/01, a SARS-CoV-2 variant first detected in the United Kingdom in September 2020, has spread to multiple countries worldwide. Several studies have established that this novel variant is more transmissible than preexisting variants of SARS-CoV-2, but have not identified whether the new variant leads to any change in disease severity. We analyse a large database of SARS-CoV-2 community test results and COVID-19 deaths for England, representing approximately 47% of all SARS-CoV-2 community tests and 7% of COVID-19 deaths in England from 1 September 2020 to 22 January 2021. Fortuitously, these SARS-CoV-2 tests can identify VOC 202012/01 because mutations in this lineage prevent PCR amplification of the spike gene target (S gene target failure, SGTF). We estimate that the hazard of death among SGTF cases is 30% (95% CI 9-56%) higher than among non-SGTF cases after adjustment for age, sex, ethnicity, deprivation level, care home residence, local authority of residence and date of test. In absolute terms, this increased hazard of death corresponds to the risk of death for a male aged 55-69 increasing from 0.56% to 0.73% (95% CI 0.60-0.86%) over the 28 days following a positive SARS-CoV-2 test in the community. Correcting for misclassification of SGTF, we estimate a 35% (12-64%) higher hazard of death associated with VOC 202012/01. Our analysis suggests that VOC 202012/01 is not only more transmissible than preexisting SARS-CoV-2 variants but may also cause more severe illness
SUSY, the Third Generation and the LHC
We develop a bottom-up approach to studying SUSY with light stops and
sbottoms, but with other squarks and sleptons heavy and beyond reach of the
LHC. We discuss the range of squark, gaugino and Higgsino masses for which the
electroweak scale is radiatively stable over the "little hierarchy" below ~ 10
TeV. We review and expand on indirect constraints on this scenario, in
particular from flavor and CP tests. We emphasize that in this context,
R-parity violation is very well motivated. The phenomenological differences
between Majorana and Dirac gauginos are also discussed. Finally, we focus on
the light subsystem of stops, sbottom and neutralino with R-parity, in order to
probe the current collider bounds. We find that 1/fb LHC bounds are mild and
large parts of the motivated parameter space remain open, while the 10/fb data
can be much more decisive.Comment: 42 pages, 8 figures, 1 table. V2: minor corrections, references adde
On-chip picosecond pulse detection and generation using graphene photoconductive switches
We report on the use of graphene for room temperature on-chip detection and generation of pulsed terahertz (THz) frequency radiation, exploiting the fast carrier dynamics of light-generated hot carriers, and compare our results with conventional low-temperature-grown gallium arsenide (LT-GaAs) photoconductive (PC) switches. Coupling of picosecond-duration pulses from a biased graphene PC switch into Goubau line waveguides is also demonstrated. A Drude transport model based on the transient photoconductance of graphene is used to describe the mechanism for both detection and generation of THz radiation
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