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Experiments in engineering are typically conducted in controlled environments where parameters can be set to any desired value. This assumes that the same applies in a real-world setting, which is often incorrect as many experiments are influenced by uncontrollable environmental conditions such as temperature, humidity, and wind speed. When optimizing such experiments, the focus should be on finding optimal values conditionally on these uncontrollable variables. This article extends Bayesian optimization to the optimization of systems in changing environments that include controllable and uncontrollable parameters. The extension fits a global surrogate model over all controllable and environmental variables but optimizes only the controllable parameters conditional on measurements of the uncontrollable variables. The method is validated on two synthetic test functions, and the effects of the noise level, the number of environmental parameters, the parameter fluctuation, the variability of the uncontrollable parameters, and the effective domain size are investigated. ENVBO, the proposed algorithm from this investigation, is applied to a wind farm simulator with eight controllable and one environmental parameter. ENVBO finds solutions for the entire domain of the environmental variable that outperform results from optimization algorithms that only focus on a fixed environmental value in all but one case while using a fraction of their evaluation budget. This makes the proposed approach very sample-efficient and cost-effective. An off-the-shelf open-source version of ENVBO is available via the NUBO Python package.
Antimicrobial stewardship programs (ASPs) exist to optimize antibiotic use, reduce selection for antimicrobial-resistant microorganisms, and improve patient outcomes. Rapid and accurate diagnosis is essential to optimal antibiotic use. Because diagnostic testing plays a significant role in diagnosing patients, it has one of the strongest influences on clinician antibiotic prescribing behaviors. Diagnostic stewardship, consequently, has emerged to improve clinician diagnostic testing and test result interpretation. Antimicrobial stewardship and diagnostic stewardship share common goals and are synergistic when used together. Although ASP requires a relationship with clinicians and focuses on person-to-person communication, diagnostic stewardship centers on a relationship with the laboratory and hardwiring testing changes into laboratory processes and the electronic health record. Here, we discuss how diagnostic stewardship can optimize the “Four Moments of Antibiotic Decision Making” created by the Agency for Healthcare Research and Quality and work synergistically with ASPs.
One in six nursing home residents and staff with positive SARS-CoV-2 tests ≥90 days after initial infection had specimen cycle thresholds (Ct) <30. Individuals with specimen Ct<30 were more likely to report symptoms but were not different from individuals with high Ct value specimens by other clinical and testing data.
Early in the COVID-19 pandemic, the World Health Organization stressed the importance of daily clinical assessments of infected patients, yet current approaches frequently consider cross-sectional timepoints, cumulative summary measures, or time-to-event analyses. Statistical methods are available that make use of the rich information content of longitudinal assessments. We demonstrate the use of a multistate transition model to assess the dynamic nature of COVID-19-associated critical illness using daily evaluations of COVID-19 patients from 9 academic hospitals. We describe the accessibility and utility of methods that consider the clinical trajectory of critically ill COVID-19 patients.
Dialysis patients may not have access to conventional renal replacement therapy (RRT) following disasters. We hypothesized that improvised renal replacement therapy (ImpRRT) would be comparable to continuous renal replacement therapy (CRRT) in a porcine acute kidney injury model.
Methods:
Following bilateral nephrectomies and 2 hours of caudal aortic occlusion, 12 pigs were randomized to 4 hours of ImpRRT or CRRT. In the ImpRRT group, blood was circulated through a dialysis filter using a rapid infuser to collect the ultrafiltrate. Improvised replacement fluid, made with stock solutions, was infused pre-pump. In the CRRT group, commercial replacement fluid was used. During RRT, animals received isotonic crystalloids and norepinephrine.
Results:
There were no differences in serum creatinine, calcium, magnesium, or phosphorus concentrations. While there was a difference between groups in serum potassium concentration over time (P < 0.001), significance was lost in pairwise comparison at specific time points. Replacement fluids or ultrafiltrate flows did not differ between groups. There were no differences in lactate concentration, isotonic crystalloid requirement, or norepinephrine doses. No difference was found in electrolyte concentrations between the commercial and improvised replacement solutions.
Conclusion:
The ImpRRT system achieved similar performance to CRRT and may represent a potential option for temporary RRT following disasters.
The Minnesota Center for Twin and Family Research (MCTFR) comprises multiple longitudinal, community-representative investigations of twin and adoptive families that focus on psychological adjustment, personality, cognitive ability and brain function, with a special emphasis on substance use and related psychopathology. The MCTFR includes the Minnesota Twin Registry (MTR), a cohort of twins who have completed assessments in middle and older adulthood; the Minnesota Twin Family Study (MTFS) of twins assessed from childhood and adolescence into middle adulthood; the Enrichment Study (ES) of twins oversampled for high risk for substance-use disorders assessed from childhood into young adulthood; the Adolescent Brain (AdBrain) study, a neuroimaging study of adolescent twins; and the Siblings Interaction and Behavior Study (SIBS), a study of adoptive and nonadoptive families assessed from adolescence into young adulthood. Here we provide a brief overview of key features of these established studies and describe new MCTFR investigations that follow up and expand upon existing studies or recruit and assess new samples, including the MTR Study of Relationships, Personality, and Health (MTR-RPH); the Colorado-Minnesota (COMN) Marijuana Study; the Adolescent Brain Cognitive Development (ABCD) study; the Colorado Online Twins (CoTwins) study and the Children of Twins (CoT) study.
To evaluate the efficacy of multiple ultraviolet (UV) light decontamination devices in a radiology procedure room.
Design
Laboratory evaluation.
Methods
We compared the efficacy of 8 UV decontamination devices with a 4-minute UV exposure time in reducing recovery of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile spores on steel disk carriers placed at 5 sites on a computed tomography patient table. Analysis of variance was used to compare reductions for the different devices. A spectrometer was used to obtain irradiance measurements for the devices.
Results
Four standard vertical tower low-pressure mercury devices achieved 2 log10CFU or greater reductions in VRE and MRSA and ~1 log10CFU reductions in C. difficile spores, whereas a pulsed-xenon device resulted in less reduction in the pathogens (P<.001). In comparison to the vertical tower low-pressure mercury devices, equal or greater reductions in the pathogens were achieved by 3 nonstandard low-pressure mercury devices that included either adjustable bulbs that could be oriented directly over the exam table, a robotic base allowing movement along the side of the table during operation, or 3 vertical towers operated simultaneously. The low-pressure mercury devices produced primarily UV-C light, whereas the pulsed-xenon device produced primarily UV-A and UV-B light. The time required to move the devices from the corner of the room and set up for operation varied from 18 to 59 seconds.
Conclusions
Many currently available UV devices could provide an effective and efficient adjunct to manual cleaning and disinfection in radiology procedure rooms.
Understanding the nutritional demands on serving military personnel is critical to inform training schedules and dietary provision. Troops deployed to Afghanistan face austere living and working environments. Observations from the military and those reported in the British and US media indicated possible physical degradation of personnel deployed to Afghanistan. Therefore, the present study aimed to investigate the changes in body composition and nutritional status of military personnel deployed to Afghanistan and how these were related to physical fitness. In a cohort of British Royal Marines (n 249) deployed to Afghanistan for 6 months, body size and body composition were estimated from body mass, height, girth and skinfold measurements. Energy intake (EI) was estimated from food diaries and energy expenditure measured using the doubly labelled water method in a representative subgroup. Strength and aerobic fitness were assessed. The mean body mass of volunteers decreased over the first half of the deployment ( − 4·6 (sd 3·7) %), predominately reflecting fat loss. Body mass partially recovered (mean +2·2 (sd 2·9) %) between the mid- and post-deployment periods (P< 0·05). Daily EI (mean 10 590 (sd 3339) kJ) was significantly lower than the estimated daily energy expenditure (mean 15 167 (sd 1883) kJ) measured in a subgroup of volunteers. However, despite the body mass loss, aerobic fitness and strength were well maintained. Nutritional provision for British military personnel in Afghanistan appeared sufficient to maintain physical capability and micronutrient status, but providing appropriate nutrition in harsh operational environments must remain a priority.
Hurricane Sandy's October 29, 2012 arrival in New York City caused flooding, power disruption, and population displacement. Infectious disease risk may have been affected by floodwater exposure, residence in emergency shelters, overcrowding, and lack of refrigeration or heating. For 42 reportable diseases that could have been affected by hurricane-related exposures, we developed methods to assess whether hurricane-affected areas had higher disease incidence than other areas of NYC.
Methods
We identified post-hurricane cases as confirmed, probable, or suspected cases with onset or diagnosis between October 30 and November 26 that were reported via routine passive surveillance. Pre-hurricane cases for the same 4-week period were identified in 5 prior years, 2007–2011. Cases were geocoded to the census tract of residence. Using data compiled by the NYC Office of Emergency Management, we determined (1) the proportion of the population in each census tract living in a flooded block and (2) the subset of flooded tracts severely “impacted”, e.g., by prolonged service outages or physical damage. A separate multivariable regression model was constructed for each disease, modeling the outcome of case counts using a negative binomial distribution. Independent variables were: neighborhood poverty; whether cases were pre- or post-hurricane (time); the proportion of the population flooded in impacted and not impacted tracts; and interaction terms between the flood/impact variables and time. Models used repeated measures to adjust for correlated observations from the same tract and an offset term of the log of the population size. Sensitivity analyses assessed the effects of case count fluctuations and accounted for variations in reporting volume by using an offset term of the log of total cases.
Results
Only legionellosis was statistically significantly associated with increased occurrence in flooded/impacted areas post-hurricane, adjusting for baseline differences (P = .04). However, there was only 1 legionellosis case post-hurricane in a flooded/impacted area.
Conclusions
Hurricane Sandy did not appear to elevate reportable disease incidence in NYC. Defining and acquiring reliable data and meta-data regarding hurricane-affected areas was a challenge in the weeks post-storm. Relevant metrics could be developed during disaster preparedness planning. These methods to detect excess disease can be adapted for future emergencies. (Disaster Med Public Health Preparedness. 2013;7:513-521)
The aim of this review paper is to consider how the principles of clinical audit could be applied to the development of an audit of nutritional care in hospitals and care homes, based on criteria derived from the Essence of Care: Food and Drink. A literature review identified fifteen key papers that included guidance or standards for nutritional care in hospitals or care homes. These were used to supplement the ten factors suggested by the Essence of Care to develop a set of potential audit criteria covering all aspects of the nutritional care pathway including the identification of risk of malnutrition, implementation of nutritional care plans, referral to healthcare professionals for further nutritional assessment and nutritional support strategies. A series of audit tools have been developed, including an organisational level audit tool, a staff questionnaire, a patients' and residents' records audit tool and a patients' and residents' experiences questionnaire. Further issues to consider in designing a national nutritional audit include the potential role of direct observation of care, the use of trained auditors and the scope for including the results of pre-existing local audits. In conclusion, a national audit would need to encompass a very large number of health and care organisations of widely varying sizes and types and a diverse range of people.
Several philosophers of science have argued that epistemically rational individuals might form epistemically irrational groups and that, conversely, rational groups might be composed of irrational individuals. We call the conjunction of these two claims the Independence Thesis, as they entail that methodological prescriptions for scientific communities and those for individual scientists are logically independent. We defend the inconsistency thesis by characterizing four criteria for epistemic rationality and then proving that, under said criteria, individuals will be judged rational when groups are not and vice versa. We then explain the implications of our results for descriptive history of science and normative epistemology.
Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene–nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient–genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.
Simultaneous, but contrary, decadal-scale changes in population trajectories of two penguin species in the western Pacific and Ross Sea sectors of the Southern Ocean, during the early/mid-1970s and again during 1988–89, correspond to changes in weather and sea ice patterns. These in turn are related to shifts in the semi-annual and Antarctic oscillations. Populations of the two ecologically dissimilar penguin species - Adélie Pygoscelis adeliae and emperor Aptenodytes forsteri - have been tallied annually since the 1950s making these the longest biological datasets for the Antarctic. Both species are obligates of sea ice and, therefore, allowing for the demographic lags inherent in the response of long-lived species to habitat or environmental variation, the proximate mechanisms responsible for the shifts involved changes in coastal wind strength and air and sea temperatures, which in turn affected the seasonal formation and decay of sea ice and polynyas. The latter probably affected such rates as the proportion of adults breeding and ultimately the reproductive output of populations in ways consistent with the two species' opposing sea ice needs. Corresponding patterns for the mid-1970s shift were reflected also in ice-obligate Weddell seal Leptonychotes weddelli populations and the structure of shallow-water sponge communities in the Ross Sea. The 1988–89 shift, by which time many more datasets had become available, was reflected among several ice-frequenting vertebrate species from all Southern Ocean sectors. Therefore, the patterns most clearly identified in the Pacific Sector were apparently spread throughout the high latitudes of the Southern Ocean.
The fourth season of the Fezzan Project continued the interdisciplinary approaches of previous seasons. Geographical and environmental work focused principally in sampling sediments for scientific dating and with integrating ground observation with remote sensing data. Excavations continued at Old Germa, where the site has now reached Garamantian levels. In a separate development, the tentative identification has been made of an early mosque at the site, in an area adjacent to the G1 excavation trench. Substantial results were gained from work aimed at enhancing the important data recorded by Charles Daniels in his earlier excavations and survey in the Wadi al-Hayat. The enhancement of the Daniels' survey archive was integrated with completion of the wider prospection being undertaken by the new project. This survey included fieldwalking, standing building survey, analysis of the foggara irrigation systems and recording of rock art scenes. Finds work comprised the finalisation of a pottery type series for the Germa area, the study of small finds from the recent survey work, botanical analysis and completion of lithics recording. A programme of radiocarbon dating is now being undertaken to improve the phasing of sites and monuments. The first two volumes of final reports are now in preparation.