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The influence of maintenance system reliability and maintainability characteristics on overall plant availability
Performance goals for complex processes are often linked with achieving high availability of plant equipment. This requires that maintenance systems, which sometimes include complex electromechanical equipment operating in a hostile environment, meet certain requirements for reliability and maintainability. This paper develops several Markov probability models to evaluate the impact of maintenance system availability on the overall plant. The models considered included the case when the maintenance equipment is itself under repair when a failure occurs on process equipment. Examination was also given to the situation where the maintenance equipment is operated in a degraded condition (i.e., longer times are required to complete repairs). The results of the analysis identified conditions under which failures in the maintenance system could have a significant adverse effect on plant availability. Maintenance system failures affect the average times required for process repairs, which can affect the availability of each process subsystem in the plant. A useful simple rule for incorporating effects of maintenance system failures into plant availability estimates is to multiply repair rates corresponding to ideal conditions (no maintenance failures) by the expected availability of the maintenance system. This rule applies when the maintenance system is available on a standby status when a process failure occurs. The effect is somewhat greater when the maintenance equipment is subject to interim breakdowns, between process failures. The analysis also indicated conditions under which overall plant availability could benefit by permitting some degradation in maintenance equipment capabilities, before repairing this equipment with a backup system. As a rough rule, the degradation should not increase average repair times by more than about a factor of two
Religion as a Cross-cultural Determinant of Depression in Elderly Europeans: Results from the EURODEP Collaboration
Background. The protective effects of religion against late life depression may depend on the broader sociocultural environment. This paper examines whether the prevailing religious climate is related to cross-cultural differences of depression in elderly Europeans.
Methods. Two approaches were employed, using data from the EURODEP collaboration. First, associations were studied between church-attendance, religious denomination and depression at the syndrome level for six EURODEP study centres (five countries, N = 8398). Secondly, ecological associations were computed by multi-level analysis between national estimates of religious climate, derived from the European Value Survey and depressive symptoms, for the pooled dataset of 13 EURODEP study centres (11 countries, N = 17739).
Results. In the first study, depression rates were lower among regular church-attenders, most prominently among Roman Catholics. In the second study, fewer depressive symptoms were found among the female elderly in countries, generally Roman Catholic, with high rates of regular church-attendance. Higher levels of depressive symptoms were found among the male elderly in Protestant countries.
Conclusions. Religious practice is associated with less depression in elderly Europeans, both on the individual and the national level. Religious practice, especially when it is embedded within a traditional value-orientation, may facilitate coping with adversity in later life
Born into adversity: psychological distress in two birth cohorts of second-generation Irish children growing up in Britain
This work was supported by the Medical Research Council
(MRC), in the form of a fellowship awarded to J.D.-M.
(grant no. G0701595/1).
PTF1 J082340.04+081936.5: A hot subdwarf B star with a low-mass white dwarf companion in an 87-minute orbit
We present the discovery of the hot subdwarf B star (sdB) binary PTF1 J082340.04+081936.5. The system has an orbital period of P orb = 87.49668(1) minutes (0.060761584(10) days), making it the second-most compact sdB binary known. The light curve shows ellipsoidal variations. Under the assumption that the sdB primary is synchronized with the orbit, we find a mass of M sdB = 0.45 +0.09 -0.07 M ⊙ , a companion white dwarf mass of M WD = 0.46 + 0.12 -0.09 M ⊙ , and a mass ratio of q = M WD /M sdB = 1.03 +0.10 -0.08 . The future evolution was calculated using the MESA stellar evolution code. Adopting a canonical sdB mass of M sdB = 0.47 M ⊙ , we find that the sdB still burns helium at the time it will fill its Roche lobe if the orbital period was less than 106 minutes at the exit from the last common envelope (CE) phase. For longer CE exit periods, the sdB will have stopped burning helium and turned into a C/O white dwarf at the time of contact. Comparing the spectroscopically derived log g and T eff with our MESA models, we find that an sdB model with a hydrogen envelope mass of 5 × 10 -4 M ⊙ matches the measurements at a post-CE age of 94 Myr, corresponding to a post-CE orbital period of 109 minutes, which is close to the limit to start accretion while the sdB is still burning helium
The first ultracompact Roche lobe-filling hot subdwarf binary
We report the discovery of the first short period binary in which a hot subdwarf star (sdOB) fills its Roche lobe and started mass transfer to its companion. The object was discovered as part of a dedicated high-cadence survey of the Galactic Plane named the Zwicky Transient Facility and exhibits a period of Porb=39.3401(1) min, making it the most compact hot subdwarf binary currently known. Spectroscopic observations are consistent with an intermediate He-sdOB star with an effective temperature of Teff=42,400±300 K and a surface gravity of log(g)=5.77±0.05. A high-signal-to noise GTC+HiPERCAM light curve is dominated by the ellipsoidal deformation of the sdOB star and an eclipse of the sdOB by an accretion disk. We infer a low-mass hot subdwarf donor with a mass MsdOB=0.337±0.015 M⊙ and a white dwarf accretor with a mass MWD=0.545±0.020 M⊙. Theoretical binary modeling indicates the hot subdwarf formed during a common envelope phase when a 2.5−2.8 M⊙ star lost its envelope when crossing the Hertzsprung Gap. To match its current Porb, Teff, log(g), and masses, we estimate a post-common envelope period of Porb≈150 min, and find the sdOB star is currently undergoing hydrogen shell burning. We estimate that the hot subdwarf will become a white dwarf with a thick helium layer of ≈0.1 M⊙ and will merge with its carbon/oxygen white dwarf companion after ≈17 Myr and presumably explode as a thermonuclear supernova or form an R CrB star
An analysis of the growth of leaf area of oil palms in Indonesia
In two cultivar × density trials for oil palms (Elaeis guineensis) planted in Indonesia, single leaf area, number of green leaves per tree, leaf opening rate per year and rachis length of leaves were followed over fourteen years. The data were analysed to determine the time course of canopy leaf area and to predict the moment of canopy closure. Growth functions were fitted to the observed data. Estimates of leaf area index (L) were based on single leaf area, number of green leaves, leaf opening and planting density. The time course of L was modelled on the basis of the fitted functions to the components. The moment of canopy closure was calculated from the planting density and the functions fitted for rachis length. The modelled time course of L was considerably different from the function fitted to the single leaf area data. The expansion of L was not as rapid as expected from the area growth of single leaves and, after maximum L was reached, a steady decline was observed. The continuously declining number of green leaves was the main cause of these two observations. The time course of L differed considerably between the two experiments. Not only were there large differences in the number of green leaves maintained per tree in the experiments but also the final area of single leaves differed between both experiments. The first factor was a result of the management of the experiments, whereas the second factor was most likely influenced by a difference in soil-related factors at the two locations. Leaf areas and numbers of leaves per tree were different for each cultivar, as was L. This was also the parameter most sensitive to planting density. Individual leaf area and leaf number per tree were not affected by planting density, but rachis length was affected by the planting density treatment. The moment of canopy closure was similar in both experiments. Planting density was the main factor that determined the onset of canopy closure
An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics
For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types
Private Narratives and Infant Views: Iconizing 1970s Militancy in Contemporary Argentine Cinema
This is the author's accepted manuscript, made available with the permission of the publisher.This article analyses the connections between the subjective turn in the representation of militancy, iconicity, and historical examination in Infancia clandestina, a recent Argentine film that portrays the 1970s armed struggle through a child’s lens. Breaking with the leading interpretation that praises the movie because of its original exposition of left-leaning violence, I contend that this coming-of-age story fits within a version of militancy that originated in the mid-1990s and that has become quite common since the advent of the Kirchner administration in 2003. This particular version relies on a privatized and archaic image of activism that is at the core of the global iconization of 1970s militancy. An analysis of the filmic use of an infant perspective and of anime-style cartoons illuminates how contemporary Argentine cinema both registers and participates in this iconizing process
Examination and prognostic implications of the unique microenvironment of breast cancer brain metastases
Purpose: Brain metastases (BM) are a complication of advanced breast cancer (BC). Histology of melanoma BM offers prognostic value; however, understanding the microenvironment of breast cancer brain metastases (BCBM) is less characterized. This study reports on four histological biomarkers, gliosis, immune infiltrate, hemorrhage, necrosis, and their prognostic significance in BCBM. Methods: A biobank of 203 human tissues from patients who underwent craniotomy for BCBM was created across four academic institutions. Degree of gliosis, immune infiltrate, hemorrhage, and necrosis were identified and scored via representative H&E stain (0–3+). Overall survival (OS) was estimated using the Kaplan–Meier method. Cox proportional hazards regression evaluated prognostic value of the biomarkers in the context of standard clinical characteristics. Results: BCBM subtype (available for n = 158) was 36% Her2+, 26% hormone receptor (HR)+/Her2− 38% HR−/Her2− (triple negative, TN). Gliosis was observed in 82% (116/141) of BCBM, with immune infiltrate 44% (90/201), hemorrhage 82% (166/141), and necrosis 87% (176/201). Necrosis was significantly higher in TNBC (p < 0.01). Presence of gliosis, immune infiltrate, and hemorrhage correlated with improved OS (p = 0.03, p = 0.03, p = 0.1), while necrosis correlated with inferior OS (p = 0.01). Improved OS was associated with gliosis in TN (p = 0.02), and immune infiltrate (p = 0.001) and hemorrhage (p = 0.07) in HER2+. In a multivariable model for OS, incorporating these biomarkers with traditional clinical variables improved the model fit (p < 0.001). Conclusion: Gliosis confers superior prognosis in TNBC BM; immune infiltrate and hemorrhage correlate with superior prognosis in HER2+ BCBM. Understanding the metastatic microenvironment of BCBM refines prognostic considerations and may unveil novel therapeutic strategies
Cardiac damage and quality of life after aortic valve replacement in the PARTNER trials
BACKGROUND The extent of extravalvular cardiac damage is associated with increased risk of adverse events among patients with severe aortic stenosis undergoing aortic valve replacement (AVR). OBJECTIVES The goal was to describe the association of cardiac damage on health status before and after AVR. METHODS Patients from the PARTNER (Placement of Aortic Transcatheter Valves) 2 and 3 trials were pooled and classified by echocardiographic cardiac damage stage at baseline and 1 year as previously described (stage 0-4). We examined the association between baseline cardiac damage and 1-year health status (assessed by the Kansas City Cardiomyopathy Questionnaire Overall Score [KCCQ-OS]). RESULTS Among 1,974 patients (794 surgical AVR, 1,180 transcatheter AVR), the extent of cardiac damage at baseline was associated with lower KCCQ scores both at baseline and at 1 year after AVR (P = 10 points) at 1 year (stages 0-4: 10.6% vs 19.6% vs 29.0% vs 44.7% vs 39.8%; P = 1 stage thorn 26.8 [95% CI: 24.2-29.4] vs no change thorn 21.4 [95% CI: 20.0-22.7] vs deterioration of >= 1 stage thorn 17.5 [95% CI: 15.4-19.5]; P < 0.0001). CONCLUSIONS The extent of cardiac damage before AVR has an important impact on health status outcomes, both cross-sectionally and after AVR. (PARTNER II Trial: Placement of AoRTic TraNscathetER Valves II -XT Intermediate and High Risk (PII A), NCT01314313; The PARTNER II Trial: Placement of AoRTic TraNscathetER Valves -PII B [PARTNERII B], NCT02184442; PARTNER 3 Trial: Safety and Effectiveness of the SAPIEN 3 Transcatheter Heart Valve in Low Risk Patients With Aortic Stenosis [P3], NCT02675114) (J Am Coll Cardiol 2023;81:743-752) (c) 2023 by the American College of Cardiology Foundation.Radiolog
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