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Mountain glaciers integrate climate processes to provide an unmatched signal of regional climate forcing. However, extracting the climate signal via intercomparison of regional glacier mass-balance records can be problematic when methods for extrapolating and calibrating direct glaciological measurements are mixed or inconsistent. To address this problem, we reanalyzed and compared long-term mass-balance records from the US Geological Survey Benchmark Glaciers. These five glaciers span maritime and continental climate regimes of the western United States and Alaska. Each glacier exhibits cumulative mass loss since the mid-20th century, with average rates ranging from −0.58 to −0.30 m w.e. a−1. We produced a set of solutions using different extrapolation and calibration methods to inform uncertainty estimates, which range from 0.22 to 0.44 m w.e. a−1. Mass losses are primarily driven by increasing summer warming. Continentality exerts a stronger control on mass loss than latitude. Similar to elevation, topographic shading, snow redistribution and glacier surface features often exert important mass-balance controls. The reanalysis underscores the value of geodetic calibration to resolve mass-balance magnitude, as well as the irreplaceable value of direct measurements in contributing to the process-based understanding of glacier mass balance.
While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis.
Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman’s test.
Median age at echocardiogram was 4.6 (range 2.5–7.4) months. Median ventricular end-diastolic pressure was 7 (range 3–19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range −35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = −0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure.
In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.
We determined how pasture and grazing management practices affected the number of days hay was fed to cattle by season. Data were collected from a survey of Tennessee cattle producers. Days of cattle on hay varied across seasons because of variations in forage production and weather. The number of days hay was fed to cattle varied with pasture-animal management practices such as rotating pastures, forage mixtures, and weed management strategies. Having mixtures of cool- and warm-season grasses reduced the number of days on hay in the winter, spring, and summer months indicating benefits from diversified forages.
Organizations all over the world, both national and international, gather demographic data so that the progress of nations and peoples can be tracked. This data is often made available to the public in the form of aggregated national level data or individual responses (microdata). Product designers likewise conduct surveys to better understand their customer and create personas. Personas are archetypes of the individuals who will use, maintain, sell or otherwise be affected by the products created by designers. Personas help designers better understand the person the product is designed for. Unfortunately, the process of collecting customer information and creating personas is often a slow and expensive process. In this paper, we introduce a new method of creating personas, leveraging publicly available databanks of both aggregated national level and information on individuals in the population. A computational persona generator is introduced that creates a population of personas that mirrors a real population in terms of size and statistics. Realistic individual personas are filtered from this population for use in product development.
Functional and mechanical properties of modern devices are directly controlled by the stress and strain state acting on the materials within. For manufacturers, elastic strain engineering of complex materials systems throughout processing and utilization is crucial. This requires methodologies with ever-increasing spatial and temporal resolutions. On the other hand, the nanoscale elastic strain field around individual defects fundamentally controls the deformation of crystalline materials. To date, a variety of techniques are available for measuring elastic strain, including transmission electron microscopy, electron backscatter diffraction, and x-ray diffraction. Recent advances in instrumentation have dramatically improved speed and resolution, enabling direct elastic strain mapping during in situ deformation at the nanoscale. In addition, plastic strain can be determined during deformation using digital image correlation. Current techniques are surveyed here to accurately quantify complex strain fields at the nanoscale and their potential to resolve scientific challenges in materials science.
Background: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length. Methods: Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors. Results: A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p <0.001). Conclusions: Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.
The Cerros del Sira in Peru is known to hold a diverse composition of endemic birds, amphibians and plants as a result of its geographical isolation, yet its mammalian community remains poorly known. There is increasing awareness of the threats to high-elevation species but studying them is often hindered by rugged terrain. We present the first camera-trap study of the mammal community of the Cerros del Sira. We used 45 camera traps placed at regular elevational intervals over 800–1,920 m, detecting 34 medium-sized and large mammal species. Eight are listed as threatened on the IUCN Red List, three are categorized as Data Deficient and one is yet to be assessed. Although other authors have reported that the upper elevations of the Cerros del Sira are free from hunting, we found evidence of hunting activity occurring above 1,400 m, and inside the core protected area. In addition to this direct evidence of hunting, recent information has identified significant amounts of canopy loss in the northern reaches of the core zone. Despite widespread ecological degradation in the surrounding lowlands, the high-elevation areas of the Cerros del Sira still maintain a unique assemblage of lowland and highland tropical rainforest mammals. It has been assumed that the Cerros del Sira and other similar remote locations are safe from disturbance and protected by their isolation but we suggest this is an increasingly dangerous assumption to make, and secure protection strategies need to be developed.
We estimate the values of bull phenotypic traits, performance measurements, and expected progeny differences (EPDs) over time using bull sale data from an auction in Tennessee from 2006 to 2016. Moreover, we determine how a state partial-cost reimbursement program for bulls with certain EPDs affects bull sale price. Purebred seed stock producers in this region should focus on selling large, fast-growing, mature bulls that produce lighter calves for reduced calving stress. The state cost-share payment did not significantly increase bull prices in most years, meaning this payment was retained by cow-calf producers in most years.
Lymphatic filariasis (LF) threatens nearly 20% of the world's population and has handicapped one-third of the 120 million people currently infected. Current control and elimination programs for LF rely on mass drug administration of albendazole plus diethylcarbamazine (DEC) or ivermectin. Only the mechanism of action of albendazole is well understood. To gain a better insight into antifilarial drug action in vivo, we treated gerbils harbouring patent Brugia malayi infections with 6 mg kg−1 DEC, 0.15 mg kg−1 ivermectin or 1 mg kg−1 albendazole. Treatments had no effect on the numbers of worms present in the peritoneal cavity of treated animals, so effects on gene expression were a direct result of the drug and not complicated by dying parasites. Adults and microfilariae were collected 1 and 7 days post-treatment and RNA isolated for transcriptomic analysis. The experiment was repeated three times. Ivermectin treatment produced the most differentially expressed genes (DEGs), 113. DEC treatment yielded 61 DEGs. Albendazole treatment resulted in little change in gene expression, with only 6 genes affected. In total, nearly 200 DEGs were identified with little overlap between treatment groups, suggesting that these drugs may interfere in different ways with processes important for parasite survival, development, and reproduction.
Sustainable design is often practiced and assessed through the consideration of three essential areas: economic sustainability, environmental sustainability, and social sustainability. For even the simplest of products, the complexities of these three areas and their tradeoffs cause decision-making transparency to be lost in most practical situations. The existing field of multiobjective optimization offers a natural framework to define and explore a given design space. In this paper, a method for defining a product’s sustainability space (defined by economic, environmental, and social sustainability objectives) is outlined and used to explore the tradeoffs within the space, thus offering both the design team and the decision makers a means of better understanding the sustainability tradeoffs. This paper concludes that sustainable product development can indeed benefit from tradeoff characterization using multiobjective optimization techniques – even when using only basic models of sustainability. Interestingly, the unique characteristics of the three essential sustainable development areas lead to an alternative view of some traditional multiobjective optimization concepts, such as weak-Pareto optimality. The sustainable redesign of a machine to drill boreholes for water wells is presented as a practical example for method demonstration and discussion.
To determine the efficacy of 2 types of antimicrobial privacy curtains in clinical settings and the costs involved in replacing standard curtains with antimicrobial curtains.
A prospective, open-labeled, multicenter study with a follow-up duration of 6 months.
This study included 12 rooms of patients with multidrug-resistant organisms (MDROs) (668 patient bed days) and 10 cubicles (8,839 patient bed days) in the medical, surgical, neurosurgical, orthopedics, and rehabilitation units of 10 hospitals.
Culture samples were collected from curtain surfaces twice a week for 2 weeks, followed by weekly intervals.
With a median hanging time of 173 days, antimicrobial curtain B (quaternary ammonium chlorides [QAC] plus polyorganosiloxane) was highly effective in reducing the bioburden (colony-forming units/100 cm2, 1 vs 57; P < .001) compared with the standard curtain. The percentages of MDRO contamination were also significantly lower on antimicrobial curtain B than the standard curtain: methicillin-resistant Staphylococcus aureus, 0.5% vs 24% (P < .001); carbapenem-resistant Acinetobacter spp, 0.2% vs 22.1% (P < .001); multidrug-resistant Acinetobacter spp, 0% vs 13.2% (P < .001). Notably, the median time to first contamination by MDROs was 27.6 times longer for antimicrobial curtain B than for the standard curtain (138 days vs 5 days; P = .001).
Antimicrobial curtain B (QAC plus polyorganosiloxane) but not antimicrobial curtain A (built-in silver) effectively reduced the microbial burden and MDRO contamination compared with the standard curtain, even after extended use in an active clinical setting. The antimicrobial curtain provided an opportunity to avert indirect costs related to curtain changing and laundering in addition to improving patient safety.
Acute reactivity of the stress hormone cortisol is reflective of early adversity and stress exposure, with some studies finding that the impact of adversity on the stress response differs by race. The objectives of the current study were to characterize cortisol reactivity to two dyadically based stress paradigms across the first year of life, to examine cortisol reactivity within Black and White infants, and to assess the impact of correlates of racial inequity including socioeconomic status, experiences of discrimination, and urban life stressors, as well as the buffering by racial socialization on cortisol patterns. Salivary cortisol reactivity was assessed at 4 months of age during the Still Face paradigm (N = 207) and at 12 months of age across the Strange Situation procedure (N = 129). Infants demonstrated the steepest recovery after the Still Face paradigm and steepest reactivity to the Strange Situation procedure. Race differences in cortisol were not present at 4 months but emerged at 12 months of age, with Black infants having higher cortisol. Experiences of discrimination contributed to cortisol differences within Black infants, suggesting that racial discrimination is already “under the skin” by 1 year of age. These findings suggest that race-related differences in hypothalamic–pituitary–adrenal reactivity are present in infancy, and that the first year of life is a crucial time period during which interventions and prevention efforts for maternal–infant dyads are most likely able to shape hypothalamic–pituitary–adrenal reactivity thereby mitigating health disparities early across the life course.
Clinicians who deal with patients with anorexia nervosa are well acquainted with their patients' inability to recognise their emaciation. The patients' insistence that they are normal weight or even overweight, against clear evidence to the contrary, led Bruch (1962) to state that the misperception reaches “delusional proportions”. Studies of body size perception in anorexia nervosa that have used the ‘body part’ method have invariably found that the patients overestimate their body size (Slade & Russell, 1973; Crisp & Kalucy, 1974; Pierloot & Houben, 1978; Garner et al, 1976; Button et al, 1977; Fries, 1977; Casper et al, 1979) but the majority have not found any significant difference in size estimation between patients and controls (Slade, 1985).