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Our current understanding of the mechanisms driving spatiotemporal yield variability in rice systems is insufficient for effective management at the sub-field scale. The overall objective of this study was to evaluate the potential of precision management for rice production. The spatiotemporal properties of multiyear yield monitor data from four rice fields, representing varying soil types and locations within the primary rice growing region in California, were quantified and characterized. The role of water management, land-leveling, and the spatial distribution of soil properties in driving yield heterogeneity was explored. Mean yield and coefficient of variation at the sampling points within each field ranged from 9.2 to 12.1 Mg ha-1 and from 7.1 to 14.5 %, respectively. Using a k-means clustering and randomization method, temporally stable yield patterns were identified in three of the four fields. Redistribution of dissolved organic carbon, nitrogen, potassium and salts by lateral flood water movement was observed across all fields, but was only related to yield variability via exacerbating areas with high soil salinity. The effects of cold water temperature and land-leveling on yield variability were not observed. Soil electrical conductivity and/or plant available phosphorus were identified as the underlying causes of the within-field yield patterns using classification and regression trees. Our results demonstrate that while the high temporal yield variability in some rice fields does not permit precision management, in other fields exhibiting stable yield patterns with identifiable causes, precision management and modified water management may improve the profitability and resource-use efficiency of rice production systems. © 2013 Springer Science+Business Media New York.

The effectiveness of land-based climate mitigation strategies is generally estimated on a case-by-case basis without considering interactions with other strategies or influencing factors. Here we evaluate a new, comprehensive approach that incorporates interactions among multiple management strategies, land use/cover change, wildfire, and climate, although the potential effects of climate change are not evaluated in this study. The California natural and working lands carbon and greenhouse gas model (CALAND) indicates that summing individual practice estimates of greenhouse gas impacts may underestimate emission reduction benefits in comparison with an integrated estimate. Annual per-area estimates of the potential impact of specific management practices on landscape emissions can vary based on the estimation period, which can be problematic for extrapolating such estimates over space and time. Furthermore, the actual area of implementation is a primary factor in determining potential impacts of management on landscape emissions. Nonetheless, less intensive forest management, avoided conversion to urban land, and urban forest expansion generally create the largest annual per-area reductions, while meadow restoration and forest fuel reduction and harvest practices generally create the largest increases with respect to no management. CALAND also shows that data uncertainty is too high to determine whether California land is a source or a sink of carbon emissions, but that estimating effects of management with respect to a baseline provides valid results. Important sources of this uncertainty are initial carbon density, net ecosystem carbon accumulation rates, and land use/cover change data. The appropriate choice of baseline is critical for generating valid results., Competing Interests: The authors have declared that no competing interests exist.

Background: Efforts to safely reduce length of stay for emergency department patients with symptoms suggestive of acute coronary syndrome (ACS) have had mixed success. Few system-wide efforts affecting multiple hospital emergency departments have ever been evaluated. We evaluated the effectiveness of a nationwide implementation of clinical pathways for potential ACS in disparate hospitals., Methods: This was a multicenter pragmatic stepped-wedge before-and-after trial in 7 New Zealand acute care hospitals with 31 332 patients investigated for suspected ACS with serial troponin measurements. The implementation was a clinical pathway for the assessment of patients with suspected ACS that included a clinical pathway document in paper or electronic format, structured risk stratification, specified time points for electrocardiographic and serial troponin testing within 3 hours of arrival, and directions for combining risk stratification and electrocardiographic and troponin testing in an accelerated diagnostic protocol. Implementation was monitored for >4 months and compared with usual care over the preceding 6 months. The main outcome measure was the odds of discharge within 6 hours of presentation RESULTS: There were 11 529 participants in the preimplementation phase (range, 284-3465) and 19 803 in the postimplementation phase (range, 395-5039). Overall, the mean 6-hour discharge rate increased from 8.3% (range, 2.7%-37.7%) to 18.4% (6.8%-43.8%). The odds of being discharged within 6 hours increased after clinical pathway implementation. The odds ratio was 2.4 (95% confidence interval, 2.3-2.6). In patients without ACS, the median length of hospital stays decreased by 2.9 hours (95% confidence interval, 2.4-3.4). For patients discharged within 6 hours, there was no change in 30-day major adverse cardiac event rates (0.52% versus 0.44%; P =0.96). In these patients, no adverse event occurred when clinical pathways were correctly followed., Conclusions: Implementation of clinical pathways for suspected ACS reduced the length of stay and increased the proportions of patients safely discharged within 6 hours., Clinical Trial Registration: URL: https://www.anzctr.org.au/ (Australian and New Zealand Clinical Trials Registry). Unique identifier: ACTRN12617000381381., (© 2017 American Heart Association, Inc.)

An understanding of cultivar effects on field greenhouse gas (GHG) emissions in rice ( L.) systems is needed to improve the accuracy of predictive models used for estimating GHG emissions and to evaluate the GHG mitigation potential of different cultivars. We compared CH and NO emissions, global warming potential (GWP = NO + CH), yield-scaled GWP (GWP = GWP Mg grain), and plant growth characteristics of eight cultivars within four study sites in California and Arkansas. Nitrous oxide emissions were negligible (<10% of GWP) and were not different among cultivars. Seasonal CH emissions differed between cultivars by a factor of 2.1 and 1.4 at one California and one Arkansas site, respectively. Plant growth characteristics were generally not correlated with seasonal CH emissions; however, the strongest correlations were observed for shoot and total plant (root + shoot) biomass at heading ( = 0.60) at one California site and for grain at maturity ( = -0.95) at one Arkansas site. Although differences in GWP and GWP were observed, there were inconsistencies across sites, indicating the importance of the genotype × environment interaction. Overall, the cultivars with the lowest CH emissions, GWP, and GWP at the California and Arkansas sites were the lowest and highest yielding, respectively. These findings highlight the potential for breeding high-yielding cultivars with low GWP, the ideal scenario to achieve low GWP, but environmental conditions must also be considered., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Background: High on clopidogrel platelet reactivity (HPR) has been associated with adverse outcomes following acute coronary syndromes (ACS). This study investigated the rate of HPR in a New Zealand ACS population and examined the effectiveness of prasugrel in reducing platelet reactivity in those with HPR., Methods: In this prospective cohort study, 250 patients with ACS were pretreated with aspirin and clopidogrel and residual platelet reactivity was measured using whole blood multiple electrode platelet aggregometry. Twenty-seven of the patients with HPR were treated with prasugrel at the discretion of their physician, and platelet reactivity retested., Results: Ninety-five patients (38%) had HPR. Maori and Pacific Island patients had a higher rate of HPR compared to Europeans (57% versus 35.9%, p=0.013). Additionally, patients with diabetes were also found to have higher rate of HPR compared to non-diabetics (50% versus 34.8%, p=0.045). Patients treated with a low dose clopidogrel regimen had significantly higher rates of HPR (45.4%) compared to those treated with intermediate (25.4%) or high dose regimens (26.8%, p=0.009). All of the 27 patients with HPR who were subsequently treated with prasugrel (60 mg) had a significant decrease in platelet reactivity (660 AU min (565-770) before versus 230 AU min (110-345) after, p<0.001), and was reduced to below the HPR cutoff in 24 (88.9%) of the patients., Conclusions: Ethnicity, diabetes and clopidogrel dose contributed to HPR. The use of prasugrel in those with HPR resulted in a consistent and marked reduction in platelet reactivity., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Background: Same-day discharge after elective percutaneous coronary intervention (PCI) is safe in the majority of patients. However, the elderly have more comorbidities and less favorable coronary and peripheral arterial anatomy, which may preclude safe same-day discharge after PCI. We assessed the feasibility and safety of same-day discharge in an elderly cohort of patients., Methods: A total of 1,580 consecutive patients undergoing elective PCI in a single center between January 2001 and January 2009 were included in the study. We compared the outcomes of elderly patients aged 75 or older to control patients under the age of 75 years. Patients were examined 6 hours post procedure and discharged if there were no complications., Results: Of the 1,580 study patients 212 (13.4%) were elderly and 1,365 (86.6%) were younger controls. The elderly were more likely to be female, hypertensive and to have had previous coronary artery bypass graft (CABG) surgery and less likely to be smokers or to have hyperlipidemia (all p < 0.05). The number of lesions treated and their complexity were similar in both groups. Procedural success, in-hospital major adverse cardiac events (MACE) and the rates of same-day discharge were also similar in both groups. Same-day discharge was achieved in the majority (84%) of the elderly. There were no deaths within 24 hours of discharge. Readmission within 24 hours of discharge was rare (< 0.7%) in both groups. The 30-day MACE rate was low in both the elderly (3.3%) and control groups (3.6%; p = 1.0)., Conclusions: Same-day discharge is safe and feasible in the majority of elderly patients following elective PCI.

Although the stigmatization of obesity among children is highly prevalent, its origins and relationship to mass media exposure are largely unknown. Ninety boys and 171 girls aged 10-13 years (mean BMI=19.84) were asked to rank, in order of liking, 12 figures of peers depicted both with and without various disabilities or obesity, and to rate their attitudes towards the obese child on visual analogue scales. Weekly time spent watching television, watching videogames, and reading magazines on weekdays and weekends was assessed. Total media use, magazine use, and videogame use were significantly correlated with more negative reactions to obese girls and boys. Regression analyses revealed that greater dislike of obese children relative to their non-overweight peers was uniquely predicted by magazine reading time. Thus, media exposure was associated with stigmatizing attitudes towards obese children. Mass media sources may lead children to devalue and stigmatize peers with above-average body weights.

This randomized trial compared a strategy of direct stenting without predilatation (n = 39) with conventional stenting with predilatation (n = 42) in patients with suitable lesions in native vessels > or = 2. 5-mm diameter to be covered by either a 9- or 16-mm-length NIR Primo stent. Equipment cost [mean (median) +/- SD] was less in those with direct stenting [$1,199 (979) +/- 526] than in those with predilatation [$1,455 (1,285) +/- 401, P < 0.001]. There was no significant difference in contrast use or fluoroscopy time. Procedural time was shorter in the direct stenting group. The clinical outcome at 1 month was satisfactory in both groups. In selected patients, a strategy of direct stenting is feasible, costs less, and is quicker to perform than the conventional strategy of stenting following predilatation.

Both resting tachycardia and irregular ventricular rhythm may contribute to impaired cardiac performance in atrial fibrillation (AF). This study assesses the relation between resting heart rate and beat-to-beat changes in left ventricular (LV) ejection and filling in patients with normal and impaired LV systolic function. Beat-to-beat variation in LV outflow and inflow velocity-time integral was measured using pulsed Doppler ultrasound in 39 patients with chronic AF and normal (n=22) or impaired (n=17) LV systolic function. Aortic velocity-time integral variability increased with mean heart rate (p=0.003) even though RR interval variability decreased (p <0.001). Aortic velocity-time integral was more sensitive to the duration of both the preceding (p <0.001) and prepreceding (p <0.001) RR intervals at higher heart rates. These relations were similar for patients with normal and impaired LV systolic function. The sensitivity of the filling velocity-time integral to RR interval variability also increased with heart rate (p <0.001). However, at higher heart rates the filling velocity-time integral (p=0.009) and filling time (p=0.005) were less sensitive to change in RR intervals in patients with impaired LV function. We conclude that beat-to-beat stroke volume variability in AF increases with heart rate. Stroke volume variability was not influenced by LV systolic function.

Warm-up exercise can significantly reduce the severity of myocardial ischemia on exercise after a 10-minute rest, but this benefit is significantly less after a 30-minute rest. Further study is needed to clarify the mechanisms responsible for warm-up. The results of this study are consistent with a change in myocardial metabolism similar to ischemic preconditioning or a delayed increase in myocardial perfusion to the ischemic territory, which has returned toward baseline after 30 minutes.

1. Plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptides (BNP) were measured, along with left and right atrial and left ventricular volumes, in eight patients with chronic renal failure before and after the removal of 2.1 +/- 0.61 of fluid by ultrafiltration and again during volume repletion with intravenous sodium chloride solution (150 mmol/l saline) to restore body weight plus 0.5 kg. 2. Baseline levels of ANP (46.0 +/- 7.5 pmol/l) and BNP (22.0 +/- 4.4 pmol/l) were elevated above normal. There was a significant reduction in plasma ANP (26.5 +/- 4.7 pmol/l, P < 0.05) and BNP (19.1 +/- 4.9 pmol/l, P < 0.05)) following ultrafiltration. Changes in plasma ANP during ultrafiltration correlated significantly with changes in left atrial volume (r = 0.643, P < 0.05). 3. During volume repletion there was an exaggerated release of ANP (mean level post repletion 71.3 +/- 20.8 pmol/l) which was not paralleled by changes in BNP. Changes in BNP were small, showing no correlation with atrial or ventricular volumes during either ultrafiltration or volume repletion. 4. These findings indicate that in chronic renal failure without left ventricular dysfunction, moderate acute changes in volume status elict only small immediate responses in plasma BNP. Changes in plasma ANP are greater than BNP and more responsive to changes in left atrial volume.

Background: Doppler echocardiographic studies have previously documented abnormalities of mitral flow during acute rejection similar to those seen in patients with "restrictive" physiology. As central venous flow is known to be abnormal in such patients, it was proposed that examination of superior vena caval flow with Doppler echocardiography might be useful for the detection of acute cardiac rejection., Methods and Results: Thirty orthotopic cardiac transplant patients, 15 of whom had acute cardiac rejection diagnosed by endomyocardial biopsy, were studied within 36 hours of biopsy. Superior vena caval Doppler flow velocities as well as mitral and tricuspid flow velocities were recorded using a Hewlett-Packard Sonos 500/1000 echocardiograph system. Examinations were performed blinded to the biopsy result. Mitral and tricuspid peak early flow velocities in the nonrejector group were similar to those seen in normal subjects (mitral, 70 +/- 5 cm/sec; tricuspid midexpiratory apnea, 50 +/- 11 cm/sec). Superior vena caval flow was abnormal with 13 of 15 patients demonstrating a biphasic pattern of forward flow with dominant diastolic flow. In the 15 patients with acute cardiac rejection, both mitral and tricuspid flow velocities developed a "restrictive"-type pattern with increased peak early flow velocities (mitral, 89 +/- 24 cm/sec; tricuspid midexpiratory apnea, 63 +/- 19 cm/sec; p < or = 0.05 versus nonrejectors) and decreased mitral early flow-velocity deceleration times (rejectors, 97 +/- 26 msec; nonrejectors, 144 +/- 41 msec; p < or = 0.05). The pattern of superior vena caval flow became markedly abnormal with a virtually complete loss of forward systolic flow (rejectors, 4.4 +/- 6.6 cm/sec; nonrejectors, 26.1 +/- 8.8 cm/sec at midexpiratory apnea; p < or = 0.0001). In 10 of 15 patients, systolic forward flow was absent. If acute rejection was defined as forward systolic flow < or = 17 cm/sec, then sensitivity was 100%, specificity was 80%, and predictive accuracy was 90%., Conclusions: During acute cardiac rejection, forward systolic superior vena caval flow is markedly diminished compared with nonrejectors. This is accompanied by other Doppler echocardiographic features consistent with the development of "restrictive" physiology. It is postulated that the loss of forward systolic flow in the superior vena cava is due to diminished long-axis shortening of the right ventricle associated with acute cardiac rejection.