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Producers often contemplate expanding or contracting production to take advantage of cyclical cattle price trends. This study quantifies profitability and risk implications of (1) constant herd size, (2) dollar cost averaging, and (3) price signal-based, anticipatory countercyclical expansion/contraction strategies. Weather simulation on forages with different calving season and land use intensity showed fall calving herds with added hay sales from greater fertilizer use and the countercyclical herd size management strategy to be most profitable regardless of weather or time period analyzed. Income risk was comparable to least fertilizer use. Overall, holding herd size constant led to little regret.
In late summer, sometime between cal a.d. 340–405, a hoard of tightly packed, stacked copper-alloy vessels was deposited in the Vale of Pewsey, Wiltshire. The corrosion of the vessels allowed for the preservation of delicate plant macrofossils and pollen. Analysis of this material has provided insights into the date, season and context of this act of structured deposition. A second hoard of similar vessels was deposited in the fourth or fifth century only a few miles away at Wilcot. The hoards and their deposition relate to Romano-British lifeways, at a time when the region was on the cusp of a dramatic period of change. The distribution of late Roman coins and belt fittings offers further insights into the social and economic character of Wiltshire at their times of deposition.
Some centres favour early intervention for ureteral colic while others prefer trial of spontaneous passage, and relative outcomes are poorly described. Calgary and Vancouver have similar populations and physician expertise, but differing approaches to ureteral colic. We studied 60-day hospitalization and intervention rates for patients having a first emergency department (ED) visit for ureteral colic in these diverse systems.
We used administrative data and structured chart review to study all Vancouver and Calgary patients with an index visit for ureteral colic during 2014. Patient demographics, arrival characteristics and triage category were captured from ED information systems, while ED visits and admissions were captured from linked regional hospital databases. Laboratory results were obtained from electronic health records and stone characteristics were abstracted from diagnostic imaging reports. Our primary outcome was hospitalization or urological intervention from 0 to 60 days. Secondary outcomes included ED revisits, readmissions and rescue interventions. Time to event analysis was conducted and Cox Proportional Hazards modelling was performed to adjust for covariate imbalance.
We studied 3283 patients with CT-defined stones. Patient and stone characteristics were similar for the cities. Hospitalization or intervention occurred in 60.9% of Calgary patients and 31.3% of Vancouver patients (p<0.001). Calgary patients had higher index intervention rates (52.1% v. 7.5%), and experienced more ED revisits and hospital readmissions during follow-up. The data suggest that outcome events were associated with overtreatment of small stones in one city and undertreatment of large stones in the other.
An early interventional approach was associated with higher ED revisit, hospitalization and intervention rates. If these events are markers of patient disability, then a less interventional approach to small stones and earlier definitive management of large stones may reduce system utilization and improve outcomes for patients with acute ureteral colic.
This study was a randomised, double-blind, placebo-controlled cross-over trial examining the effects of β-hydroxy β-methylbutyrate free acid (HMB-FA) supplementation on muscle protein breakdown, cortisol, testosterone and resting energy expenditure (REE) during acute fasting. Conditions consisted of supplementation with 3 g/d HMB-FA or placebo during a 3-d meat-free diet followed by a 24-h fast. Urine was collected before and during the 24-h fast for analysis of 3-methylhistidine:creatinine ratio (3MH:CR). Salivary cortisol, testosterone, their ratio (T:C), and the cortisol awakening response were assessed. ANOVA was used to analyse all dependent variables, and linear mixed models were used to confirm the absence of carryover effects. Eleven participants (six females, five males) completed the study. Urinary HMB concentrations confirmed compliance with supplementation. 3MH:CR was unaffected by fasting and supplementation, but the cortisol awakening response differed between conditions. In both conditions, cortisol increased from awakening to 30 min post-awakening (P=0·01). Cortisol was reduced from 30 to 45 min post-awakening with HMB-FA (−32 %, d=−1·0, P=0·04), but not placebo (PL) (−6 %, d=−0·2, P=0·14). In males, T:C increased from 0 to 24 h of fasting with HMB-FA (+162 %, d=3·0, P=0·001), but not placebo (+13 %, d=0·4, P=0·60), due to reductions in cortisol. REE was higher at 24 h of fasting than 16 h of fasting independent of supplementation (+4·0 %, d=0·3, P=0·04). In conclusion, HMB-FA may affect cortisol responses, but not myofibrillar proteolysis, during acute 24-h fasting.
Fee-for-service payment may motivate physicians to see more patients and achieve higher productivity. In 2015, emergency physicians at one Vancouver hospital switched to fee-for-service payment, while those at a sister hospital remained on contract, creating a natural experiment where the compensation method changed, but other factors remained constant. Our hypothesis was that fee-for-service payment would increase physician efficiency and reduce patient wait times.
This interrupted time series with concurrent control analysed emergency department (ED) performance during a 42-week period, encompassing the intervention (fee for service). Data were aggregated by week and plotted in a time series fashion. We adjusted for autocorrelation and developed general linear regression models to assess level and trend changes. Our primary outcome was the wait time to physician.
Data from 142,361 ED visits were analysed. Baseline wait times rose at both sites during the pre-intervention phase. Immediately post-intervention, the median wait time increased by 2.4 minutes at the control site and fell by 7.2 minutes at the intervention site (difference=9.6 minutes; 95% confidence interval, 2.9-16.4; p=0.007). The wait time trend (slope) subsequently deteriorated by 0.5 minutes per week at the intervention site relative to the expected counterfactual (p for the trend difference=0.07). By the end of the study, cross-site differences had not changed significantly from baseline.
Fee-for-service payment was associated with a 9.6-minute (24%) reduction in wait time, compatible with an extrinsic motivational effect; however, this was not sustained, and the intervention had no impact on other operational parameters studied. Physician compensation is an important policy issue but may not be a primary determinant of ED operational efficiency.
Hemispheric asymmetry is commonly viewed as a dual system, unique to humans, with the two sides of the human brain in complementary roles. To the contrary, modern research shows that cerebral and behavioral asymmetries are widespread in the animal kingdom, and that the concept of duality is an oversimplification. The brain has many networks serving different functions; these are differentially lateralized, and involve many genes. Unlike the asymmetries of the internal organs, brain asymmetry is variable, with a significant minority of the population showing reversed asymmetries or the absence of asymmetry. This variability may underlie the divisions of labor and the specializations that sustain social life. (JINS, 2017, 23, 710–718)
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
Obsessive-compulsive disorder (OCD) is associated with variable risk of suicide and prevalence of suicide attempt (SA). The present study aimed to assess the prevalence of SA and associated sociodemographic and clinical features in a large international sample of OCD patients.
A total of 425 OCD outpatients, recruited through the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network, were assessed and categorized in groups with or without a history of SA, and their sociodemographic and clinical features compared through Pearson’s chi-squared and t tests. Logistic regression was performed to assess the impact of the collected data on the SA variable.
14.6% of our sample reported at least one SA during their lifetime. Patients with an SA had significantly higher rates of comorbid psychiatric disorders (60 vs. 17%, p<0.001; particularly tic disorder), medical disorders (51 vs. 15%, p<0.001), and previous hospitalizations (62 vs. 11%, p<0.001) than patients with no history of SA. With respect to geographical differences, European and South African patients showed significantly higher rates of SA history (40 and 39%, respectively) compared to North American and Middle-Eastern individuals (13 and 8%, respectively) (χ2=11.4, p<0.001). The logistic regression did not show any statistically significant predictor of SA among selected independent variables.
Our international study found a history of SA prevalence of ~15% in OCD patients, with higher rates of psychiatric and medical comorbidities and previous hospitalizations in patients with a previous SA. Along with potential geographical influences, the presence of the abovementioned features should recommend additional caution in the assessment of suicide risk in OCD patients.
To determine the source of a healthcare-associated outbreak of Pantoea agglomerans bloodstream infections.
Epidemiologic investigation of the outbreak.
Oncology clinic (clinic A).
Cases were defined as Pantoea isolation from blood or catheter tip cultures of clinic A patients during July 2012–May 2013. Clinic A medical charts and laboratory records were reviewed; infection prevention practices and the facility’s water system were evaluated. Environmental samples were collected for culture. Clinical and environmental P. agglomerans isolates were compared using pulsed-field gel electrophoresis.
Twelve cases were identified; median (range) age was 65 (41–78) years. All patients had malignant tumors and had received infusions at clinic A. Deficiencies in parenteral medication preparation and handling were identified (eg, placing infusates near sinks with potential for splash-back contamination). Facility inspection revealed substantial dead-end water piping and inadequate chlorine residual in tap water from multiple sinks, including the pharmacy clean room sink. P. agglomerans was isolated from composite surface swabs of 7 sinks and an ice machine; the pharmacy clean room sink isolate was indistinguishable by pulsed-field gel electrophoresis from 7 of 9 available patient isolates.
Exposure of locally prepared infusates to a contaminated pharmacy sink caused the outbreak. Improvements in parenteral medication preparation, including moving chemotherapy preparation offsite, along with terminal sink cleaning and water system remediation ended the outbreak. Greater awareness of recommended medication preparation and handling practices as well as further efforts to better define the contribution of contaminated sinks and plumbing deficiencies to healthcare-associated infections are needed.
Although intravenous thrombolysis increases the probability of a good
functional outcome in carefully selected patients with acute ischemic
stroke, a substantial proportion of patients who receive thrombolysis do not
have a good outcome. Several recent trials of mechanical thrombectomy appear
to indicate that this treatment may be superior to thrombolysis. We
therefore conducted a systematic review and meta-analysis to evaluate the
clinical effectiveness and safety of new-generation mechanical thrombectomy
devices with intravenous thrombolysis (if eligible) compared with
intravenous thrombolysis (if eligible) in patients with acute ischemic
stroke caused by a proximal intracranial occlusion. We systematically
searched seven databases for randomized controlled trials published between
January 2005 and March 2015 comparing stent retrievers or thromboaspiration
devices with best medical therapy (with or without intravenous thrombolysis)
in adults with acute ischemic stroke. We assessed risk of bias and overall
quality of the included trials. We combined the data using a fixed or random
effects meta-analysis, where appropriate. We identified 1579 studies; of
these, we evaluated 122 full-text papers and included five randomized
control trials (n=1287). Compared with patients treated medically, patients
who received mechanical thrombectomy were more likely to be functionally
independent as measured by a modified Rankin score of 0-2 (odds ratio, 2.39;
95% confidence interval, 1.88-3.04; I2=0%). This finding was
robust to subgroup analysis. Mortality and symptomatic intracerebral
hemorrhage were not significantly different between the two groups.
Mechanical thrombectomy significantly improves functional independence in
appropriately selected patients with acute ischemic stroke.
Existing population studies of deep-sea amphipods have focused on species that inhabit deep-sea vent or trench environments but few cosmopolitan species have been studied. Here we provide new insight into the life history and population ecology of the pan-oceanic scavenging amphipod Paralicella caperesca and discuss the influence of nutrient-rich submarine canyon environments on the growth and reproduction of this species. Data were collected through the dissection and measurement of 2997 P. caperesca from 14 samples taken from abyssal plains, continental slopes and submarine canyons in the North-East Atlantic. Sexual dimorphism was less pronounced than observed for other scavenging amphipod species but females were significantly larger and had shorter antennae than males. The size of oostegites in female P. caperesca varied considerably within size classes, ovaries contained a relatively large number of oocytes, and no empty ovaries were observed. These factors, in combination with absence of mature females, suggest that P. caperesca practices semelparity, a reproductive strategy that complements the feeding strategy of this obligate necrophage. Five male and seven female size-grouped cohorts were identified for P. caperesca. Cohorts from deep-sea submarine canyon populations showed consistently larger mean total body lengths than non-canyon cohorts. Individuals from canyon samples also expressed sexual characteristics at smaller sizes than non-canyon individuals. We hypothesize that these trends are indicative of nutrient-mediated growth, maturation, and reproduction in P. caperesca. The species is able to grow and reproduce relatively quickly in response to increased nutrient input in canyon environments and therefore dominates scavenging amphipod assemblages.
In October 2008, Medicare ceased additional payment for hospital-acquired conditions not present on admission. We evaluated the policy’s differential impact in hospitals with high vs low operating margins. Medicare’s payment policy may have had an impact on reducing central line–associated bloodstream infections in hospitals with low operating margins.
Infect. Control Hosp. Epidemiol. 2015;37(1):100–103
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Mutations in Cyclin-Dependent Kinase Inhibitor 2A (CDKN2A) and Cyclin-Dependent Kinase 4 (CDK4) contribute to susceptibility in approximately 40% of high-density cutaneous melanoma (CMM) families and about 2% of unselected CMM cases. BRCA-1 associated protein-1 (BAP1) has been more recently shown to predispose to CMM and uveal melanoma (UMM) in some families; however, its contribution to CMM development in the general population is unreported. We sought to determine the contribution of these genes to CMM susceptibility in a population-based sample of cases from Australia. We genotyped 1,109 probands from Queensland families and found that approximately 1.31% harbored mutations in CDKN2A, including some with novel missense mutations (p.R22W, p.G35R and p.I49F). BAP1 missense variants occurred in 0.63% of cases but no CDK4 variants were observed in the sample. This is the first estimate of the contribution of BAP1 and CDK4 to a population-based sample of CMM and supports the previously reported estimate of CDKN2A germline mutation prevalence.