bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impacts of harvesting on brine shrimp (Artemia franciscana) in Great Salt Lake, Utah, USA
Authors: Sura Shayna A. , Belovsky Gary E. 
Published: May 2016

AbstractSelective harvesting can cause evolutionary responses in populations via shifts in phenotypic characteristics, especially those affecting life history. Brine shrimp (Artemia franciscana) cysts in Great Salt Lake (GSL), Utah, USA are commercially harvested with techniques that select against floating cysts. This selective pressure could cause evolutionary changes over time. Our objectives are to (1) determine if there is a genetic basis to cyst buoyancy, (2) determine if cyst buoyancy and nauplii mortality have changed over time, and (3) to examine GSL environmental conditions over time to distinguish whether selective harvesting pressure or a trend in environmental conditions caused changes in cyst buoyancy and nauplii mortality. Mating crosses between floating and sinking parental phenotypes with two food concentrations (low and high) indicated there is a genetic basis to cyst buoyancy. Using cysts harvested from 1991–2011, we found cyst buoyancy decreased and nauplii mortality increased over time. Data on water temperature, salinity, and chlorophyll a concentration in GSL from 1994 to 2011 indicated that although water temperature has increased over time and chlorophyll a concentration has decreased over time, the selective harvesting pressure against floating cysts is a better predictor of changes in cyst buoyancy and nauplii mortality over time than trends in environmental conditions. Harvesting of GSL A. franciscana cysts is causing evolutionary changes, which has implications for the sustainable management and harvesting of these cysts. Monitoring phenotypic characteristics and life‐history traits of the population should be implemented and appropriate responses taken to reduce the impacts of the selective harvesting.
Nitrogen Fertilizer and Seeding Rate Influence on Grain and Forage Yield of Dual‐Purpose Barley
Authors: Hajighasemi S. , Keshavarz‐Afshar R. , Chaichi M. R. 
Published: May 2016

Clipping fall‐sown cereals provides a good source of high‐quality forage during late winter. Farmers usually use more inputs, including fertilizers and seed, in dual‐purpose systems compared with grain‐only systems. A 2‐yr field study was conducted in Karaj, Iran, to evaluate the effects of nitrogen (N) rates (0, 50, 100, 150 kg N ha−1) and seeding rates (400, 600, 800 seed m−2) on forage and grain yields of two barley (Hordeum vulgare L.) cultivars (Fasih and CB 744) in grain‐only and dual‐purpose systems. Fasih and CB 744 grain yields in the grain‐only system were 2996 and 3250 kg ha−1, respectively (averaged over experimental treatments). Forage removal in the dual‐purpose system resulted in 25% grain yield penalty. Despite the lower grain yield, the economic return of the dual‐purpose system was considerably greater due to the high price of forage during late winter in the region. Grain yield response to N was linear in the grain‐only system, but the trend was not significant in the dual‐purpose system. In both production systems, grain yield response to seeding rate was quadratic, and the highest yields of both cultivars (2534 and 3192 kg ha−1 for Fasih and CB 744, respectively) were obtained from 600 seed m−2. In both production systems, 600 seed m−2 and 100 kg N ha−1 were optimum for grain and forage production. Our results showed considerably higher revenue in the dual‐purpose system compared with the grain‐only system in this region. Moreover, no additional inputs of N and seed are required for dual‐purpose barley than those usually used in a grain‐only system.Core Ideas

Dual‐purpose barley yielded 25% less grain than that in grain‐only system.
Despite a lower grain yield, economic return of dual‐purpose barley was considerably greater.
In both production systems, 600 seed m−2 and 100 kg N ha−1 were optimum for grain and forage production.
No additional N and seed are required for dual‐purpose barley than those usually used in grain‐only system.
Assessing the Success of Regional Measures for Lowering Agricultural Nutrient Pollution in Headwater Streams
Authors: Barry C. D. , Foy R. H. 
Published: May 2016

Lowland waters in Northern Ireland experience elevated agricultural phosphorus (P) inputs, and in response a variety of control measures targeting farm nutrient management have been implemented. Their efficacy in lowering nitrogen (N) and P exports and improving water quality is examined in 40 headwater streams from 1990 to 2009, and to 2014 for 24 of these. Over this period manure production in the study catchments declined by 7%, but regional chemical fertilizer inputs declined by 37% for N and 79% for P, and the regional nutrient surplus was lowered by 18% for N and 49% for P. Diminished pollution by organic wastes meant that 85% of streams exhibited chemistry suitable for salmonids in 2009 compared to 40% in 1990. Flow‐weighted mean concentrations (FWMCs) of nutrients declined between 1990 and 2009, and their correlations with catchment stocking rates became stronger over time. For catchments with manure inputs <16.6 kg P ha−1, total P and nitrate FWMCs declined from 123 ± 19 μg P L−1and 1.92 ± 0.5 mg N L−1in 1990 at rates of 2.2 ± 0.5 and 30 ± 10 μg L−1yr−1, respectively. For catchments with higher manure inputs the respective rates of decline were greater at 5.8 ± 1.0 μg P L−1yr−1and 160 ± 20 μg N L−1yr−1from 1990 concentrations of 270 ± 25 μg P L−1and 5.99 ± 0.4 mg N L−1. Although now lower, P concentrations in the more highly stocked catchments still exceed regional nutrient standards so that the identification of further factors impinging on nutrient losses is critical if such standards are to be achieved.Core IdeasAmelioration of point source and diffuse agricultural pollution over 20 years.Reductions to diffuse N export more rapid and pronounced than for P.Nutrient versus land use intensity correlations stronger after pollution amelioration.
Effect of Harsh or Mild Extraction of Soil on Pesticide Leaching to Groundwater
Authors: Boesten Jos J. T. I. 
Published: May 2016

Assessment of leaching to groundwater is an important aspect of pesticide risk assessment. The first leaching tier usually consists of simulations with leaching scenarios based on pesticide–soil properties derived from laboratory studies. Because the extractability of pesticide residues in such studies decreases with time, the harshness of the extraction method influences these pesticide–soil properties. This study investigates the effect of using a mild or harsh extraction method on simulated leaching to groundwater with consideration of substances with a range of half‐lives and organic matter sorption coefficient values for selected leaching scenarios. The model for linking the concentrations of the mild and the harsh systems was based on laboratory studies with two pesticides and a Dutch sandy soil and was tested against Canadian field studies with atrazine (6‐chloro‐N2‐ethyl‐N4‐isopropyl‐1,3,5‐triazine‐2,4‐diamine). The degradation rate and the aged‐sorption parameters of each “mild” soil–substance system were derived from a hypothetical laboratory incubation study using prescribed parameter values for the corresponding “harsh” soil–substance system. Simulations were performed for three European leaching scenarios (United Kingdom, France, Portugal). For the best‐guess parameter set, the leaching concentrations of the harsh system were approximately equal to those of the mild system at leaching concentrations greater than 1 μg L−1 and were at most approximately a factor of two higher than those of the mild systems at mild leaching concentrations between 0.01 and 0.1 μg L−1. However, an extreme parameter set led to harsh leaching concentrations that were at most approximately 10 times higher than the mild leaching concentrations at levels between 0.01 and 0.1 μg L−1.Core Ideas
First model for the effect of harsh or mild extraction on pesticide behavior in soil.
A model based on a Dutch study produced acceptable simulation of Canadian field data.
The effect of harsh or mild extraction on pesticide leaching is comparatively small.
Mild extraction generates faster apparent degradation but less aged sorption.
Determining Soil Stress beneath a Tire: Measurements and Simulations
Authors: Keller Thomas , Ruiz Siul , Stettler Matthias , Berli Markus 
Published: May 2016

Core Ideas
Bolling probe pressure is a function of soil mean normal stress and the soil's Poisson ratio.
Vertical soil stress could be well described by the Boussinesq solution.
Simulations reveal a significant impact of soil properties on mean normal stress.
This study measured soil stress underneath a rolling wheel by using two different types of sensors: a load cell type probe referred to as an Arvidsson probe to read vertical soil stress and a fluid inclusion type sensor referred to as a Bolling probe to read soil mean normal stress. Measurements were compared with simulations using a semi‐empirical as well as a finite element model. The latter allowed us to consider a layered soil profile as well as an elastoplastic constitutive relationship in the simulations. In addition, the finite element model was used to quantify the ratio between the Bolling probe pressure and the soil mean normal stress. The Bolling probe pressure was found to be primarily a function of the soil's Poisson ratio, which supports findings from earlier studies. Our results showed better agreement between measurements and simulations for vertical stress (obtained from the Arvidsson probe readings) than for mean normal stress (calculated from the Bolling probe measurements). The finite element simulations revealed that soil properties had little influence on vertical stress, and the distribution with depth of the vertical stress could be well described by the classical Boussinesq solution. However, soil properties had a significant impact on the mean normal stress. The widely used semi‐empirical Fröhlich model performed poorly, which may have been because of an inconsistency in the model assumptions.
Predictors of 30-Day Hospital Readmission among Maintenance Hemodialysis Patients: A Hospital’s Perspective
Authors: Flythe Jennifer E. , Katsanos Suzanne L. , Hu Yichun , Kshirsagar Abhijit V. , Falk Ronald J. , Moore Carlton R. 
Published: May 2016

Background and objectivesOver 35% of patients on maintenance dialysis are readmitted to the hospital within 30 days of hospital discharge. Outpatient dialysis facilities often assume responsibility for readmission prevention. Hospital care and discharge practices may increase readmission risk. We undertook this study to elucidate risk factors identifiable from hospital-derived data for 30-day readmission among patients on hemodialysis.Design, setting, participants, & measurementsData were taken from patients on maintenance hemodialysis discharged from University of North Carolina Hospitals between May of 2008 and June of 2013 who received in-patient hemodialysis during their index hospitalizations. Multivariable logistic regression models with 30-day readmission as the dependent outcome were used to identify readmission risk factors. Models considered variables available at hospital admission and discharge separately.ResultsAmong 349 patients, 112 (32.1%) had a 30-day hospital readmission. The discharge (versus admission) model was more predictive of 30-day readmission. In the discharge model, malignancy comorbid condition (odds ratio [OR], 2.08; 95% confidence interval [95% CI], 1.04 to 3.11), three or more hospitalizations in the prior year (OR, 1.97; 95% CI, 1.06 to 3.64), ≥10 outpatient medications at hospital admission (OR, 1.69; 95% CI, 1.00 to 2.88), catheter vascular access (OR, 1.82; 95% CI, 1.01 to 3.65), outpatient dialysis at a nonuniversity–affiliated dialysis facility (OR, 3.59; 95% CI, 2.03 to 6.36), intradialytic hypotension (OR, 3.10; 95% CI, 1.45 to 6.61), weekend discharge day (OR, 1.82; 95% CI, 1.01 to 3.31), and serum albumin <3.3 g/dl (OR, 4.28; 95% CI, 2.37 to 7.73) were associated with higher readmission odds. A decrease in prescribed medications from admission to discharge (OR, 0.20; 95% CI, 0.08 to 0.51) was associated with lower readmission odds. Findings were robust across different model–building approaches.ConclusionsModels containing discharge day data had greater predictive capacity of 30-day readmission than admission models. Identified modifiable readmission risk factors suggest that improved medication education and improved transitions from hospital to community may potentially reduce readmissions. Studies evaluating targeted transition programs among patients on dialysis are needed.
Objective Gait and Balance Impairments Relate to Balance Confidence and Perceived Mobility in People With Parkinson Disease
Authors: Curtze Carolin , Nutt John G. , Carlson-Kuhta Patricia , Mancini Martina , Horak Fay B. 
Published: May 2016

Abstract

Background
Body-worn, inertial sensors can provide many objective measures of balance and gait. However, the objective measures that best reflect patient perception of mobility disability and clinician assessment of Parkinson disease (PD) are unknown.

Objective
The purposes of this study were: (1) to determine which objective measures of balance and gait are most related to patient perception of mobility disability and disease severity in people with PD and (2) to examine the effect of levodopa therapy on these correlates.

Design
This was an experimental correlation study.

Methods
One hundred four people with idiopathic PD performed 3 trials of the Instrumented Stand and Walk Test (ISAW) in the “on” and “off” medication states. The ISAW consists of quiet standing (30 seconds), gait initiation, straight walking (7 m), and turning (180°), yielding 34 objective measures of mobility from body-worn inertial sensors. Patient perception of mobility disability was assessed with the Activities-specific Balance Confidence (ABC) scale and the mobility subscale of the Parkinson's Disease Questionnaire (PDQ-39). Disease severity was assessed with the Unified Parkinson's Disease Rating Scale, part III (motor UPDRS). Spearman correlations were used to relate objective measures of mobility to patient perception and disease severity.

Results
Turning speed, gait speed, and stride length were most highly correlated to severity of disease and patient perception of mobility disability. The objective measures of mobility in the off-medication state were more indicative of patient perception of mobility disability and balance confidence compared with on-medication state measures.

Limitations
Causation is an inherent problem of correlation studies.

Conclusion
Physical therapists should evaluate mobility in people with PD in the off-medication state because the off-medication state is more related to disease severity and patient perception of mobility disability than the on-medication state mobility. Assessment and treatment of mobility in people with PD should target specific measures (ie, turning, gait speed, and stride length) because these measures best reflect patients' quality of life and balance confidence.
Learning from failure: persistence of aneurysms following pipeline embolization
Authors: Shapiro Maksim , Becske Tibor , Nelson Peter K. 
Published: May 2016

OBJECTIVE
A detailed analysis was performed of anterior circulation aneurysms treated with a Pipeline Embolization Device (PED) that did not progress to complete occlusion by 1-year follow-up. Angiography was performed with the purpose of identifying specific factors potentially responsible for these failed outcomes.

METHODS
From among the first 100 patients with anterior circulation aneurysms, 92 underwent 1-year follow-up angiography and were individually studied through review of their pre- and postembolization studies.

RESULTS
Nineteen aneurysms (21%) remained unoccluded at 12 months. Independent predictors of treatment failure, identified by logistic regression analysis, were found to be fusiform aneurysm morphology, decreasing dome-to-neck ratio, and the presence of a preexisting laser-cut stent. Further examination of individual cases identified several common mechanisms—device malapposition, inadequate coverage of the aneurysm neck with persistent exchange across the device, and the incorporation of a branch vessel into the aneurysm fundus—potentially contributing to failed treatment in these settings.

CONCLUSIONS
Attention to specific features of the aneurysm and device construct can frequently identify cases predisposed to treatment failure and suggest strategies to maximize favorable outcomes.
Operating room waste: disposable supply utilization in neurosurgical procedures
Authors: Zygourakis Corinna C. , Yoon Seungwon , Valencia Victoria , Boscardin Christy , Moriates Christopher , Gonzales Ralph , Lawton Michael T. 
Published: May 2016

OBJECTIVE
Disposable supplies constitute a large portion of operating room (OR) costs and are often left over at the end of a surgical case. Despite financial and environmental implications of such waste, there has been little evaluation of OR supply utilization. The goal of this study was to quantify the utilization of disposable supplies and the costs associated with opened but unused items (i.e., “waste”) in neurosurgical procedures.

METHODS
Every disposable supply that was unused at the end of surgery was quantified through direct observation of 58 neurosurgical cases at the University of California, San Francisco, in August 2015. Item costs (in US dollars) were determined from the authors' supply catalog, and statistical analyses were performed.

RESULTS
Across 58 procedures (36 cranial, 22 spinal), the average cost of unused supplies was $653 (range $89-$3640, median $448, interquartile range $230–$810), or 13.1% of total surgical supply cost. Univariate analyses revealed that case type (cranial versus spinal), case category (vascular, tumor, functional, instrumented, and noninstrumented spine), and surgeon were important predictors of the percentage of unused surgical supply cost. Case length and years of surgical training did not affect the percentage of unused supply cost. Accounting for the different case distribution in the 58 selected cases, the authors estimate approximately $968 of OR waste per case, $242,968 per month, and $2.9 million per year, for their neurosurgical department.

CONCLUSIONS
This study shows a large variation and significant magnitude of OR waste in neurosurgical procedures. At the authors' institution, they recommend price transparency, education about OR waste to surgeons and nurses, preference card reviews, and clarification of supplies that should be opened versus available as needed to reduce waste.
Can the anxiety domain of EQ-5D and mental health items from SF-36 help predict outcomes after surgery for lumbar degenerative disorders?
Authors: Carreon Leah Y. , Djurasovic Mladen , Dimar John R. , Owens R. Kirk , Crawford Charles H. , Puno Rolando M. , Bratcher Kelly R. , McGraw Katlyn E. , Glassman Steven D. 
Published: May 2016

OBJECTIVE
Studies have shown that anxious or depressed patients may have poorer outcomes after lumbar fusion. These conclusions were drawn from questionnaires specifically designed to measure anxiety and depression. The objective of this study is to determine if responses to the EQ-5D anxiety/depression domain or the items used to calculate the 36-Item Short-Form Health Survey (SF-36) Mental Component Summary (MCS) can predict outcomes after lumbar fusion surgery.

METHODS
Patients enrolled in the National Neurosurgery Quality and Outcomes Database from a single center with 1-year follow-up were identified. The outcomes collected include the Oswestry Disability Index (ODI), EQ-5D, SF-36, and the back- and leg-pain numeric rating scales (range 0–10). Linear regression modeling was performed to predict the 1-year ODI scores using the EQ-5D anxiety/depression domain and the 14 items used to calculate SF-36 MCS.

RESULTS
Complete data were available for 312 (88%) of 353 eligible patients. The mean patient age was 58.5 years, 175 (56%) patients were women, and 52 patients were smokers. After controlling for other factors, the item in the SF-36 that asks “Have you felt downhearted and depressed?” is the strongest predictor of the 1-year ODI score (r2 = 0.191; p = 0.000) and 1-year EQ-5D score (r2 = 0.205; p = 0.000). Neither the EQ-5D anxiety/depression domain nor the diagnoses of anxiety or depression were predictors of 1-year outcomes.

CONCLUSIONS
Patient responses to SF-36 item “Have you felt downhearted and depressed?” account for 20% of the variability of the 1-year ODI and EQ-5D scores and can be used by clinicians to screen for anxiety or depression in patients prior to lumbar fusion surgery. Clinicians may offer psychological support to these patients preoperatively in order to improve treatment outcomes.
Prophylactic adjacent-segment vertebroplasty following kyphoplasty for a single osteoporotic vertebral fracture and the risk of adjacent fractures: a retrospective study and clinical experience
Authors: Eichler Martin C. , Spross Christian , Ewers Alexander , Mayer Ryan , Külling Fabrice A. 
Published: May 2016

OBJECTIVE
This study investigated the benefit of prophylactic vertebroplasty of the adjacent vertebrae in single-segment osteoporotic vertebral body fractures treated with kyphoplasty.

METHODS
All patients treated with kyphoplasty for osteoporotic single-segment fractures between January 2007 and August 2012 were included in this retrospective study. The patients received either kyphoplasty alone (kyphoplasty group) or kyphoplasty with additional vertebroplasty of the adjacent segment (vertebroplasty group). The segmental kyphosis with the rate of adjacent-segment fractures (ASFs) and remote fractures were studied on plain lateral radiographs preoperatively, postoperatively, at 3 months, and at final follow-up.

RESULTS
Thirty-seven (82%) of a possible 45 patients were included for the analysis, with a mean follow-up of 16 months (range 3–54 months). The study population included 31 women, and the mean age of the total patient population was 72 years old (range 53–86 years). In 21 patients (57%), the fracture was in the thoracolumbar junction. Eighteen patients were treated with additional vertebroplasty and 19 with kyphoplasty only. The segmental kyphosis increased in both groups at final follow-up. A fracture through the primary treated vertebra (kyphoplasty) was found in 4 (22%) of the vertebroplasty group and in 3 (16%) of the kyphoplasty group (p = 0.6). An ASF was found in 50% (n = 9) of the vertebroplasty group and in 16% (n = 3) of the kyphoplasty group (p = 0.03). Remote fractures occurred in 1 patient in each group (p = 1.0).

CONCLUSIONS
Prophylactic vertebroplasty of the adjacent vertebra in patients with single-segment osteoporotic fractures as performed in this study did not decrease the rate of adjacent fractures. Based on these retrospective data, the possible benefits of prophylactic vertebroplasty do not compensate for the possible risks of an additional cement augmentation.