Completeness, robustness, and safety in real-time software requirements specification

This paper presents an approach to providing a rigorous basis for ascertaining whether or not a given set of software requirements is internally complete, i.e., closed with respect to questions and inferences that can be made on the basis of information included in the specification. Emphasis is placed on aspects of software requirements specifications that previously have not been adequately handled, including timing abstractions, safety, and robustness

Looking for Pure Rotational H_2 Emission from Protoplanetary Disks

We report on a limited search for pure-rotational molecular hydrogen emission associated with young, pre-main-sequence stars. We looked for H_2 v=0 J = 3->1 and J = 4->2 emission in the mid-infrared using the Texas Echelon-Cross-Echelle Spectrograph (TEXES) at NASA's 3m Infrared Telescope Facility. The high spectral and spatial resolution of our observations lead to more stringent limits on narrow line emission close to the source than previously achieved. One star, AB Aur, shows a possible (2sigma) H_2 detection, but further observations are required to make a confident statement. Our non-detections suggest that a significant fraction, perhaps all, of previously reported H_2 emission towards these objects could be extended on scales of 5" or more.Comment: 14 pages including 2 figures. Accepted by ApJ Letter

Troponin Elevations After Electroconvulsive Therapy: The Need for Caution

BACKGROUND: Electroconvulsive therapy is used to treat patients with severe or resistant depression. Troponin elevations are associated with an adverse prognosis, and it is well known that central nervous system insults can cause biochemical evidence of cardiac injury. No study previously has studied this with electroconvulsive therapy. METHODS: Patients scheduled for electroconvulsive therapy were enrolled. Clinical information, an electrocardiogram, and a baseline sample for cardiac troponin I and T (cTnI and cTnT) were obtained. Electroconvulsive therapy was done with standard techniques. Subsequently, electrocardiograms and additional samples were obtained. cTnT was measured with the Roche assay and cTnI with the Dade Stratus equipment. Values above the 99th percentile were considered abnormal. RESULTS: Seventy patients completed the study. Four patients had elevated levels of cTn before treatment. In 3 patients, the elevations persisted. Four additional patients developed elevated cTn levels during electroconvulsive therapy. Two of the patients with cTn elevations died. No other events occurred during follow-up. CONCLUSIONS: Elevations of cTn occurred in 11.5% of patients treated with electroconvulsive therapy. Some of the elevations preceded therapy and some occurred during treatment. Given the adverse prognostic importance of cTn elevations in general, in addition to additional studies, an increased degree of medical scrutiny may be appropriate for this group of patients and for those receiving electroconvulsive therapy

Sensitive detection of somatic point mutations in impure and heterogeneous cancer samples

Detection of somatic point substitutions is a key step in characterizing the cancer genome. Mutations in cancer are rare (0.1–100/Mb) and often occur only in a subset of the sequenced cells, either due to contamination by normal cells or due to tumor heterogeneity. Consequently, mutation calling methods need to be both specific, avoiding false positives, and sensitive to detect clonal and sub-clonal mutations. The decreased sensitivity of existing methods for low allelic fraction mutations highlights the pressing need for improved and systematically evaluated mutation detection methods. Here we present MuTect, a method based on a Bayesian classifier designed to detect somatic mutations with very low allele-fractions, requiring only a few supporting reads, followed by a set of carefully tuned filters that ensure high specificity. We also describe novel benchmarking approaches, which use real sequencing data to evaluate the sensitivity and specificity as a function of sequencing depth, base quality and allelic fraction. Compared with other methods, MuTect has higher sensitivity with similar specificity, especially for mutations with allelic fractions as low as 0.1 and below, making MuTect particularly useful for studying cancer subclones and their evolution in standard exome and genome sequencing data

Non-relativistic effective theory of dark matter direct detection

Dark matter direct detection searches for signals coming from dark matter scattering against nuclei at a very low recoil energy scale ~ 10 keV. In this paper, a simple non-relativistic effective theory is constructed to describe interactions between dark matter and nuclei without referring to any underlying high energy models. It contains the minimal set of operators that will be tested by direct detection. The effective theory approach highlights the set of distinguishable recoil spectra that could arise from different theoretical models. If dark matter is discovered in the near future in direct detection experiments, a measurement of the shape of the recoil spectrum will provide valuable information on the underlying dynamics. We bound the coefficients of the operators in our non-relativistic effective theory by the null results of current dark matter direct detection experiments. We also discuss the mapping between the non-relativistic effective theory and field theory models or operators, including aspects of the matching of quark and gluon operators to nuclear form factors.Comment: 35 pages, 3 figures, Appendix C.3 revised, acknowledgments and references adde

Posttraumatic stress disorder and type 2 diabetes outcomes in veterans

IMPORTANCE: Posttraumatic stress disorder (PTSD) symptom reduction is linked with lower risk of incident type 2 diabetes (T2D), but little is known about the association between PTSD and comorbid T2D outcomes. Whether PTSD is a modifiable risk factor for adverse T2D outcomes is unknown. OBJECTIVE: To determine whether patients with PTSD who improved and no longer met diagnostic criteria for PTSD had a lower risk of adverse T2D outcomes compared with patients with persistent PTSD. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used deidentified data from US Veterans Health Administration (VHA) historical medical records (from October 1, 2011, to September 30, 2022) to create a cohort of patients aged 18 to 80 years with comorbid PTSD and T2D. Data analysis was performed from March 1 to June 1, 2024. EXPOSURES: Diagnoses of PTSD and T2D. MAIN OUTCOMES AND MEASURES: The main outcomes were insulin initiation, poor glycemic control, any microvascular complication, and all-cause mortality. Improvement of PTSD was defined as no longer meeting PTSD diagnostic criteria, per a PTSD Checklist score of less than 33. Entropy balancing controlled for confounding. Survival and competing risk models estimated the association between meeting PTSD criteria and T2D outcomes. Subgroup analyses examined variation by age, sex, race, PTSD severity, and comorbid depression status. RESULTS: The study cohort included 10 002 veterans. More than half of patients (65.3%) were aged older than 50 years and most (87.2%) were men. Patients identified as Black (31.6%), White (62.7%), or other race (5.7%). Before controlling for confounding with entropy balancing, patients who no longer met PTSD diagnostic criteria had similar incidence rates for starting insulin (22.4 vs 24.4 per 1000 person-years), poor glycemic control (137.1 vs 133.7 per 1000 person-years), any microvascular complication (108.4 vs 104.8 per 1000 person-years), and all-cause mortality (11.2 vs 11.0 per 1000 person-years) compared with patients with persistent PTSD. After controlling for confounding, no longer meeting PTSD criteria was associated with a lower risk of microvascular complications (hazard ratio [HR], 0.92 [95% CI, 0.85-0.99]). Among veterans aged 18 to 49 years, no longer meeting PTSD criteria was associated with a lower risk of insulin initiation (HR, 0.69 [95% CI, 0.53-0.88]) and all-cause mortality (HR, 0.39 [95% CI, 0.19-0.83]). Among patients without depression, no longer meeting PTSD criteria was associated with a lower risk of insulin initiation (HR, 0.73 [95% CI, 0.55-0.97]). CONCLUSIONS AND RELEVANCE: The findings of this cohort study of patients with comorbid PTSD and T2D suggest that PTSD is a modifiable risk factor associated with a modest reduction in microvascular complications. Further research is needed to determine whether findings are similar in non-VHA health care settings

The initial mass function of early-type galaxies

We determine an absolute calibration of the initial mass function (IMF) of early-type galaxies, by studying a sample of 56 gravitational lenses identified by the SLACS Survey. Under the assumption of standard Navarro, Frenk & White dark matter halos, a combination of lensing, dynamical, and stellar population synthesis models is used to disentangle the stellar and dark matter contribution for each lens. We define an "IMF mismatch" parameter \alpha=M*(L+D)/M*(SPS) as the ratio of stellar mass inferred by a joint lensing and dynamical models (M*(L+D)) to the current stellar mass inferred from stellar populations synthesis models (M*(SPS)). We find that a Salpeter IMF provides stellar masses in agreement with those inferred by lensing and dynamical models (=0.00+-0.03+-0.02), while a Chabrier IMF underestimates them (=0.25+-0.03+-0.02). A tentative trend is found, in the sense that \alpha appears to increase with galaxy velocity dispersion. Taken at face value, this result would imply a non universal IMF, perhaps dependent on metallicity, age, or abundance ratios of the stellar populations. Alternatively, the observed trend may imply non-universal dark matter halos with inner density slope increasing with velocity dispersion. While the degeneracy between the two interpretations cannot be broken without additional information, the data imply that massive early-type galaxies cannot have both a universal IMF and universal dark matter halos.Comment: 10 pages 4 figures. Resubmitted to ApJ taking into account referee's comment

Instrumentation progress at the Giant Magellan Telescope project

Instrument development for the 24m Giant Magellan Telescope (GMT) is described: current activities, progress, status, and schedule. One instrument team has completed its preliminary design and is currently beginning its final design (GCLEF, an optical 350-950 nm, high-resolution and precision radial velocity echelle spectrograph). A second instrument team is in its conceptual design phase (GMACS, an optical 350-950 nm, medium resolution, 6-10 arcmin field, multiobject spectrograph). A third instrument team is midway through its preliminary design phase (GMTIFS, a near-IR YJHK diffraction-limited imager/integral-field-spectrograph), focused on risk reduction prototyping and design optimization. A fourth instrument team is currently fabricating the 5 silicon immersion gratings needed to begin its preliminary design phase (GMTNIRS, a simultaneous JHKLM high-resolution, AO-fed, echelle spectrograph). And, another instrument team is focusing on technical development and prototyping (MANIFEST, a facility robotic, multifiber-feed, with a 20 arcmin field of view). In addition, a medium-field (6 arcmin, 0.06 arcsec/pix) optical imager will support telescope and AO commissioning activities, and will excel at narrow-band imaging. In the spirit of advancing synergies with other groups, the challenges of running an ELT instrument program and opportunities for cross-ELT collaborations are discussed

Benchmark Parameters for CMB Polarization Experiments

The recently detected polarization of the cosmic microwave background (CMB) holds the potential for revealing the physics of inflation and gravitationally mapping the large-scale structure of the universe, if so called B-mode signals below 10^{-7}, or tenths of a uK, can be reliably detected. We provide a language for describing systematic effects which distort the observed CMB temperature and polarization fields and so contaminate the B-modes. We identify 7 types of effects, described by 11 distortion fields, and show their association with known instrumental systematics such as common mode and differential gain fluctuations, line cross-coupling, pointing errors, and differential polarized beam effects. Because of aliasing from the small-scale structure in the CMB, even uncorrelated fluctuations in these effects can affect the large-scale B modes relevant to gravitational waves. Many of these problems are greatly reduced by having an instrumental beam that resolves the primary anisotropies (FWHM << 10'). To reach the ultimate goal of an inflationary energy scale of 3 \times 10^{15} GeV, polarization distortion fluctuations must be controlled at the 10^{-2}-10^{-3} level and temperature leakage to the 10^{-4}-10^{-3} level depending on effect. For example pointing errors must be controlled to 1.5'' rms for arcminute scale beams or a percent of the Gaussian beam width for larger beams; low spatial frequency differential gain fluctuations or line cross-coupling must be eliminated at the level of 10^{-4} rms.Comment: 11 pages, 5 figures, submitted to PR

Differences in designations of observation care in US freestanding children's hospitals: Are they virtual or real?

OBJECTIVE: To characterize practices related to observation care and to examine the current models of pediatric observation medicine in US children's hospitals. DESIGN: We utilized 2 web‐based surveys to examine observation care in the 42 hospitals participating in the Pediatric Health Information System database. We obtained information regarding the designation of observation status, including the criteria used to admit patients into observation. From hospitals reporting the use of observation status, we requested specific details relating to the structures of observation care and the processes of care for observation patients following emergency department treatment. RESULTS: A total of 37 hospitals responded to Survey 1, and 20 hospitals responded to Survey 2. Designated observation units were present in only 12 of 31 (39%) hospitals that report observation patient data to the Pediatric Health Information System. Observation status was variably defined in terms of duration of treatment and prespecified criteria. Observation periods were limited to <48 hours in 24 of 31 (77%) hospitals. Hospitals reported that various standards were used by different payers to determine observation status reimbursement. Observation care was delivered in a variety of settings. Most hospitals indicated that there were no differences in the clinical care delivered to virtual observation status patients when compared with other inpatients. CONCLUSIONS: Observation is a variably applied patient status, defined differently by individual hospitals. Consistency in the designation of patients under observation status among hospitals and payers may be necessary to compare quality outcomes and costs, as well as optimize models of pediatric observation care. Journal of Hospital Medicine 2012;. © 2011 Society of Hospital Medicine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91108/1/949_ftp.pd