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Background: Age is the most significant predictor of Alzheimer's disease and related dementias (ADRD). Biological age, in contrast to chronological age, is modifiable – shaped by environmental and social factors which contribute to the functional declines observed in aging. Accelerated biological aging has been observed in historically underrepresented populations in ADRD research who are at highest risk for developing ADRD. Telomere length (TL) is a marker of biological age and empirically associated with cognitive aging. However, this association has not been investigated in historically underrepresented populations such as American Indians / Alaska Natives (AI/AN). This study reports on the utility of TL to predict cognitive performance in a sample of middle‐aged and older adults from Wisconsin communities historically underrepresented in ADRD research. Method: The Wisconsin Alzheimer's Disease Research Center's (WADRC) Inclusion of Underrepresented Groups Core engages AI/AN, Blacks / African Americans (B/AA), and participants of multi‐race and ethnicity identities through community based participatory research practices. A sample (n = 188) identifying their race as AI/AN or B/AA were included if they provided whole blood and completed the Rey Auditory Verbal Learning Test (RAVLT, Trials 1‐5) and the Trails Making Test (TMT, A and B times) for verbal learning and executive functioning, respectively. DNA was extracted from whole blood and analyzed with monochrome multiplex quantitative polymerase chain reaction for TL. Multivariable linear regression analyses tested relationships between TL and cognitive test performance. Result: The participants (mean age = 60.88 ±9.06) were majority female, with 79.26% B/AA and 12.77% AI/AN (Table 1). In bivariate analyses, TL significantly correlated with all outcomes: longer telomeres correlated with better verbal learning and executive functioning performance (Figure 1A‐C). In multivariable regression models, TL significantly predicted cognitive performance for all outcomes independent of participant sex, race, age, and cognitive status (Table 2). Conclusion: These findings suggest that TL is a strong predictor of cognitive performance for historically underrepresented populations, offering potential opportunities for screening of accelerated biological aging and interventions. The community‐led research at the WADRC makes this analysis the first of its kind to include AI/AN participants. Future ADRD research should consider behavioral and socioeconomic interventions shown to modify biological aging. [ABSTRACT FROM AUTHOR]

Background: Agitation in Alzheimer's Disease (Agit‐AD) is a common and troubling neuropsychiatric syndrome which adds significantly to disability and caregiver stress. Behavioral interventions lack consistent efficacy and there are no FDA‐approved medications. Neurobiological mechanisms that contribute to Agit‐AD include brain atrophy, degradation of neurotransmission, neuroinflammation, disrupted circadian rhythms, comorbidities and frailty. Agit‐AD is a major source of disease progression, patient disability, financial burden, and caregiver stress. Dronabinol is a synthetic cannabinoid (tetrahydrocannabinol, THC). Cannabinoids may improve Agit‐AD by providing protection against neuroinflammation and excitotoxicity, regulating neurotransmitters, improving comorbidities, stabilizing circadian rhythms, and increasing cerebral blood flow. Method: THC‐AD is a three‐week placebo‐controlled, double‐blind, RCT of dronabinol (10 mg QD) in 80 patients with severe Agit‐AD. Twice daily administration maximizes daytime coverage for agitation and minimizes sundowning. Inclusionary criteria include a diagnosis of AD, severe agitation, and being 60‐95 years old, while exclusionary criteria include serious or unstable medical illness, seizure disorder, delirium, current use of lithium, and inability to swallow a pill. Primary outcomes include a change in the Pittsburgh Agitation Scale and NPI‐C Agitation/Aggression subscales. Result: We have enrolled 58 out of targeted 80 participants (Table 1: mean age 77.8 years, 65.5% female, 87.9% Caucasian, mean education 13.8 years, 45.6% family history). On average, study participants are very cognitively impaired (Table 2: mean baseline MMSE of 8.1), very agitated (mean NPI‐C Agitation 14.6, mean NPI‐C Aggression 6.3) and in reasonable overall health (Figure 1: General Medical Health Rating, 12.1% "excellent," 51.7% "good" and 34.5% "fair"). Recorded AEs have been tolerable (Figure 2). Due to the COVID‐19 pandemic, we expanded our inpatient trial to include outpatient enrollments and implemented hybrid visits with telemedicine to limit in‐person interactions. We also added a supplemental study to evaluate the effects of the pandemic on caregiver stress and burden. We are collaborating with additional clinical sites, increasing dementia bed capacity, and deploying recruitment strategies for outpatients, including referrals from providers and other research trials, social media ads, and virtual community outreach. Conclusion: Safe and effective interventions for severe agitation are greatly needed. This pilot trial will help to examine the safety and efficacy of dronabinol for Agit‐AD. [ABSTRACT FROM AUTHOR]

The global decline of coral reefs urgently requires scalable colony‐level data about phenotypic variation to improve coral conservation and management. To address this, we leveraged historical bleaching phenotypes, airborne imaging spectroscopy, and recurrent temperature stress to map coral species composition and thermal tolerance across four focal reefs with a cumulative area of ~15 ha. Spectral data accurately distinguished benthic composition and coral species, and showed substantial capacity for mapping thermal tolerance in two species of healthy coral. We used thermal stress from a 2019 marine heatwave to demonstrate high prediction accuracy during a natural bleaching event, and to strengthen the links between predictions, conserved tolerance phenotypes, and spectral signatures. Large differences in the proportion of tolerant corals at individual reefs suggest that ecosystem‐scale "winners" and "losers" in future bleaching can be predicted, which may greatly increase the efficacy of management. This framework provides foundational evidence for the applicability of organismic‐scale remote sensing to coral conservation. [ABSTRACT FROM AUTHOR]

Corn (Zea mays L.) stover is an increasingly important feedstock for biofuel and bioproduct production; however, excessive harvest of corn stover from agricultural fields may affect corn seedling emergence and subsequent plant population which may reduce corn growth and yield. Field experiments were conducted over four consecutive growing seasons in southwestern Ontario to determine under continuous corn cropping system the effects of no‐tillage (NT), conventional tillage (CT), and five rates of stover harvest (0, 25, 50, 75, and 100 wt. %) on corn seedling emergence in a Harrow sandy loam and in a Brookston clay loam. Time to achieve 50% seedling emergence (t0.5), emergence rate constant (kG), and final seedling population (MG) were adequately simulated using the Gompertz function. Irrespective of stover removal rate and soil type, t0.5 was 2 d longer, and kG was 32% lower, under NT compared to CT. In Harrow sandy loam, stover removal from NT reduced t0.5 in 1 out of 4 yr. The 100% removal reduced t0.5 relative to 0, 25, 50, and 75% removal by 1.1–2.2 d in 2015. Averaged across both tillages and all removal rates, kG was greater in Harrow sandy loam than in Brookston clay loam. Stover removal rates had no effect on MG but averaged over all removal rates and soil types, MG was 9% lower for NT compared to CT in 2016. No‐tillage practice under corn production can impede seedlings emergence early in the growing season and stover removal from the field can help mitigate against this effect. Core Ideas: Time to 50% emergence was 2 d longer under no‐tillage compared to conventional tillage.Time to 50% emergence was shorter with 100% stover removal in the sandy loam soil under no‐tillage.Final corn emergence (MG) in no‐tillage was reduced relative to conventional tillage in both soils in only 1 out of 4 yr.Emergence rate constant (kG) was 77% greater for the conventional tillage than the no‐tillage. [ABSTRACT FROM AUTHOR]

Crop yields are often lower during the "three-year transition" period from conventional to organic production systems. This paper presents the results from an organic cropping trial which used summer-seeded legume cover crops as the primary N source for corn in a corn (Zea mays L.)- soybean (Glycine max (L.) Merr)-winter wheat (Triticum aestivum L.) rotation in southwestern Ontario, Canada. The cover crop treatments included crimson clover (CC, Trifolium incarnatum L.), hairy vetch (HV, Vicia villosa Roth subsp. villosa) and red clover (RC, Trifolium pratense L.). Also included were a conventional control (CKC, with synthetic fertilizers) and an organic control (CKO, no synthetic fertilizer) without cover crops. The objectives were to determine the N and C accumulation in the legume above-ground biomass; the impacts of cover crops on residual soil mineral N (RSN) in late fall and on crop grain yields during the 3-yr transition period. Compared to CKC, cover crops left less RSN (51 kg N ha-1 less) in the soil profile (0-90 mm) by late November. In early May before plow-down, significantly more above-ground biomass was found for HV (3313 kg C ha-1, 240 kg N ha-1) and RC (2766 kg C ha-1, 199 kg N ha-1) than for CC (1787 kg C ha-1, 119 kg N ha-1). In the three-year transition period, average corn grain yields were 13.1 and 13. 0 Mg ha-1 for HV and RC which were similar (P = 0.05) to CKC (13.8 Mg ha-1) but greater than CKO (6.4 Mg ha-1) (P = 0.05). This study highlighted the effectiveness of using HV or RC as a primary N source for organic corn production in southwestern Ontario. [ABSTRACT FROM AUTHOR]

Water repellency of agricultural crop residues may affect the hydrologic balance and increase runoff loss of pesticides by greater wash off from hydrophobic residue. We conducted a laboratory study to measure water repellency and hydrophobicity of 30 major agricultural crops (grass, legume, cereal, oilseed, pulse, and specialty crops). Crop samples were collected in southern Alberta, Canada in 2017 and 2018. Water repellency (WR) of oven-dried (60°C) and ground (<2 mm) crop residues was measured using the water drop penetration time (WDPT) and molarity of ethanol (MED) tests. Hydrophobicity was evaluated using the ratio of hydrophobic CH-- to hydrophilic CO--functional groups using Fourier Transform Infrared (FTIR) spectroscopy. The WDPTs of the 30 agricultural crops ranged from 8.3 to 2438 s, suggesting that crop species influenced WR of the dried and undecomposed residues. Needle-and-thread grass (Stipa comata Trin. and Rupr.), blue grama (Bouteloua gracilis [Kunth] Lag. ex Griffiths), and western wheatgrass (Agropyron smithii Rydb.) were the most WR crops based on WDPT. Fababean (Vicia faba), mustard (Sinapis alba L.), and sweet clover (Melilotus officinalis) were the least WR crops. Mean WDPTs were significantly (P ≤ 0.05) greater for grass than the other four crop types by 23 to 44 times. Significant differences in WDPT occurred among crop species within each of the six crop types. A significant positive correlation occurred between WDPT and hydrophobicity (r = 0.54), but not between WDPT and organic carbon. Overall, crop type and species may influence WR of crop residues and could affect the hydrologic balance. [ABSTRACT FROM AUTHOR]

There is an incentive for dairy farmers to maximize crop production while minimizing costs and environmental impacts. In cold climates, farmers have limited opportunity to balance field activities and manure storage requirements while limiting nutrient losses. A revised DeNitrification DeComposition (DNDC) model for simulating tile drainage was used to investigate fertilizer scenarios when applying dairy slurry or urea on silage corn (Zea mays L.) to examine N losses over a multidecadal horizon at locations in eastern Canada and the US Midwest. Management scenarios included timing (spring, fall, split, and sidedress) and method of application (injected [10 cm], incorporated [5 cm], and broadcast). Reactive N losses (NO3− from drainage and runoff, N2O, and NH3) were greatest from broadcast, followed by incorporated and then injected applications. Among the fertilizer timing scenarios, fall manure application resulted in the greatest N loss, primarily due to increased N leaching in non‐growing‐season periods, with 58% more N loss per metric ton of silage than spring application. Split and sidedress mineral fertilizer had the lowest N losses, with average reductions of 9.5 and 4.9%, respectively, relative to a single application. Split application mitigated losses more so than sidedress by reducing the soil pH shift due to urea hydrolysis and NH3 volatilization during the warmer June period. This assessment helps to distinguish which fertilizer practices are more effective in reducing N loss over a long‐term time horizon. Reactive N loss is ranked across 18 fertilizer management practices, which could assist farmers in weighing the tradeoffs between field trafficability, manure storage capacity, and expected N loss. Core Ideas: The impacts of climate variability were often greater than the impacts of fertilizer management.Fall‐applied manure resulted in more N loss than spring‐applied, primarily from N leaching.Lowest N loss occurred from split and sidedress urea at all three locations.More NH3 volatilization and N2O losses occurred from organic fertilizer, but N leaching was similar.Similar fertilizer management recommendations can be made across all three locations. [ABSTRACT FROM AUTHOR]

Surface runoff and tile drainage are the main pathways for water movement and entry of agricultural nitrate into water resources. The objective of this 5-yr study was to characterize the partitioning of water flow and nitrate loss between these pathways for a humid-temperate Brookston clay loam soil under 54 to 59 yr of consistent cropping and fertilization. Cropping treatments included monoculture corn (Zea mays L., MC), continuous bluegrass (Poa pratensis L.) sod (CS), and a corn--oat--alfalfa (Medicago sativa L.)--alfalfa rotation (RC--RO--RA1--RA2). Fertilization treatments included annual fertilizer addition (F) and no fertilizer addition (NF). Tile drainage and surface runoff occurred primarily during the nongrowing season (November-April), and they were highly correlated with the mean saturated hydraulic conductivity of the near-surface soil profile. Tile drainage accounted for 69 to 90% of cumulative water flow and 79 to 96% of cumulative nitrate loss from fertilized rotation and CS, whereas surface runoff accounted for the majority of the nitrate losses in MC (i.e., 75-93% of water flow and 65-96% of nitrate loss). Cumulative nitrate losses were highest in the RC-F (152 kg N ha-1), RC-NF (101 kg N ha-1), RA2-NF (121 kg N ha-1), and RA2-NF (75 kg N ha-1) plots, and these high losses are attributed to N mineralization from the plowed alfalfa and fertilization (if applicable). Fertilization increased cumulative nitrate loss in tile drainage from all treatments, whereas no fertilization increased cumulative nitrate loss in surface runoff from the rotation. Cropping system and fertilization on clay loam soil changed how water flow and nitrate loss were partitioned between tile drainage and surface runoff. [ABSTRACT FROM AUTHOR]

Agricultural practices such as including perennial alfalfa (Medicago sativa L.), winter wheat (Triticum aestivum L.), or red clover (Trifolium pratense L.) in corn (Zea mays L.) rotations can provide higher crop yields and increase soil organic C (SOC) over time. How well process-based biogeochemical models such as DeNitrification- DeComposition (DNDC) capture the beneficial effects of diversified cropping systems is unclear. To calibrate and validate DNDC for simulation of observed trends in corn yield and SOC, we used long-term trials: continuous corn (CC) and corn--oats (Avena sativa L.)-- alfalfa--alfalfa (COAA) for Woodslee, ON, 1959 to 2015; and CC, corn--corn--soybean [Glycine max (L.) Merr.]--soybean (CCSS), corn--corn--soybean--winter wheat (CCSW), corn--corn--soybean--winter wheat + red clover (CCSW+Rc), and corn--corn--alfalfa--alfalfa (CCAA) for Elora, ON, 1981 to 2015. Yield and SOC under 21st century conditions were projected under future climate scenarios from 2016 to 2100. The DNDC model was calibrated to improve crop N stress and was revised to estimate changes in water availability as a function of soil properties. This improved yield estimates for diversified rotations at Elora (mean absolute prediction error [MAPE] decreased from 13.4-15.5 to 10.9-14.6%) with lower errors for the three most diverse rotations. Significant improvements in yield estimates were also simulated at Woodslee for COAA, with MAPE decreasing from 24.0 to 16.6%. Predicted and observed SOC were in agreement for simpler rotations (CC or CCSS) at both sites (53.8 and 53.3 Mg C ha-1 for Elora, 52.0 and 51.4 Mg C ha-1 for Woodslee). Predicted SOC increased due to rotation diversification and was close to observed values (58.4 and 59 Mg C ha-1 for Elora, 63 and 61.1 Mg C ha-1 for Woodslee). Under future climate scenarios the diversified rotations mitigated crop water stress resulting in trends of higher yields and SOC content in comparison to simpler rotations. [ABSTRACT FROM AUTHOR]

Surface streaming urea ammonium nitrate (UAN) into corn (Zea mays L.) at side-dress (v4-v6) or later in the season (v12-v14) is an emerging N fertilizer application method as it is rapid, reduces soil disturbance, and allows for flexible application times. In 2013 and 2014, side-dress N application (130 kg N ha-1) using three streaming UAN sources was evaluated for their ability to maintain grain yield, reduce ammonia (NH3) volatilization, and mitigate nitrous oxide (N2O) emissions. The products included streaming of urea ammonium nitrate (StrUAN), urea ammonium nitrate with a urease inhibitor (StrUAN-UI), urea ammonium nitrate with urease inhibitor plus nitrification inhibitor (StrUAN-UI+NI), and a control (no N). The efficacy of streaming relative to traditional shallow- injected urea ammonium nitrate (InjUAN) was also assessed. Delayed NH3 sampling related to wind-tunnel installation in 2013 and 2014 led to additional NH3 measurements in 2015 and 2016. Average yields from StrUAN were 11% lower relative to InjUAN. The use of inhibitors did not improve yields relative to StrUAN. Ammonia volatilization was not significantly different between StrUAN and InjUAN losing 14 and 20% of applied N (2-yr average), respectively. However in 2015 and 2016, NH3 volatilization from StrUAN was 3.6-fold greater than InjUAN when measurements were started immediately after application. Hence lower yields in 2013 and 2014 from StrUAN likely reflect N loss to rapid volatilization during or shortly after application. The StrUAN-UI treatment increased 2-yr average N2O emissions by 17.3 to 18.7% relative to StrUAN or StrUAN-UI+NI. For humid-temperate clay loam soil, UAN streaming with/without inhibitors was not effective for maintaining yields or reducing NH3 volatilization. [ABSTRACT FROM AUTHOR]

Less than 50% of applied nitrogen (N) fertilizer is typically recovered by corn (Zea mays L.) due to climatic constraints, soil degradation, overapplication, and losses to air and water. Two application methods, two N sources, and two inhibitors were evaluated to reduce N losses and enhance crop uptake. The treatments included broadcast urea (BrUrea), BrUrea with a urease inhibitor (BrUrea+UI), BrUrea with a urease and a nitrification inhibitor (BrUrea+UI+NI), injection of urea ammonium nitrate (InjUAN), and injected with one or both inhibitors (InjUAN+UI, InjUAN+UI+NI), and a control. The BrUrea treatment lost 50% (64.4 kg N ha-1) of the applied N due to ammonia volatilization, but losses were reduced by 64% with BrUrea+UI+NI (23.0 kg N ha-1) and by 60% with InjUAN (26.1 kg N ha-1). Ammonia losses were lower and crop yields were greater in 2014 than 2013 as a result of the more favorable weather when N was applied in 2014. When ammonia volatilization was reduced by adding a urease inhibitor, N2O emissions were increased by 30 to 31% with BrUrea+UI and InjUAN+UI compared with BrUrea and InjUAN, respectively. Pollution swapping was avoided when both inhibitors were used (BrUrea+UI+NI, InjUAN+UI+NI) as both ammonia volatilization and N2O emissions were reduced, and corn grain yields increased by 5% with BrUrea+UI+NI and by 7% with InjUAN+UI+NI compared with BrUrea and InjUAN, respectively. The combination of two N management strategies (InjUAN+UI+NI) increased yields by 19% (12.9 t ha-1) compared with BrUrea (10.8 t ha-1). [ABSTRACT FROM AUTHOR]

Long-term application of feedlot manure to cropland may increase the quantity of soil organic carbon (C) and change its quality, which may influence soil water repellency. The objective was to determine the influence of feedlot manure type (stockpiled vs. composted), bedding material (straw [ST] vs. woodchips [WD]), and application rate (13, 39, or 77 Mg ha-1) on repellency of a clay loam soil after 17 annual applications. The repellency was determined on all 14 treatments using the water repellency index (R index), the water drop penetration time (WDPT) method, and molarity of ethanol (MED) test. The C composition of particulate organic matter in soil of five selected treatments after 16 annual applications was also determined using 13C nuclear magnetic resonance-direct polarization with magic-angle spinning (NMRDPMAS). Manure type had no significant (P > 0.05) effect on R index and WDPT, and MED classification was similar. Mean R index and WDPT values were significantly greater and MED classification more hydrophobic for WD than ST. Application rate had no effect on the R index, but WDPT was significantly greater and MED classification more hydrophobic with increasing application rate. Strong (r > 0.7) but nonsignificant positive correlations were found between R index and WDPT versus hydrophobic (alkyl + aromatic) C, lignin at 74 ppm (O-alkyl), and unspecified aromatic compounds at 144 ppm. Specific aromatic compounds also contributed more to repellency than alkyl, O-alkyl, and carbonyl compounds. Overall, all three methods consistently showed that repellency was greater for WD- than ST-amended clay loam soil, but manure type had no effect. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) yield is relatively low in eastern Canada. This study aimed to assess fertilizer N management options to improve the regional yield of wheat using the CSM- CERES-Wheat model. The model was adapted to simulate winter wheat by replacing air temperatures wiThestimated temperatures under snow cover, and then the model was evaluated for simulating winter wheat using experimental data collected at two sites and spring wheat at three sites in eastern Canada. Across all the experimental years and sites, the normalized root mean squared error (nRMSE) between simulated and measured yields was 14%. Regional yield under rainfed conditions in the Eastern Ontario Region (a Census of Agriculture unit as a case study) was simulated wiTh0, 1, 1.5, and 2 times the recommended N rate (around 50 kg N ha-1) and unlimited N for the calibrated cultivars of spring wheat from 1981 to 1999. The simulated average regional yield (in dry matter) wiThthe recommended N rate ranged from 2180 kg ha-1 for cultivar Hoffman to 2502 kg ha-1 for AC Brio. BoThwere close to the reported yield of 2440 kg ha-1, wiThnRMSE values ranging between 20.3 and 16.6%. The simulated regional yields wiThunlimited N were two times that wiThthe recommended N rate, showing a considerable yield gap. Our simulations indicate that regional yield could increase to 3600 kg ha-1 in the Eastern Ontario Region if the N rate was increased to around 100 kg N ha-1, although a slight decrease in N use efficiency would occur. In addition, wiThsuch increases in the N fertilization rate, other abiotic factors such as lodging should be evaluated. [ABSTRACT FROM AUTHOR]

Long-term application of feedlot manure to cropland may influence soil mesofauna. These organisms affect the health, structure, and fertility of soils, organic matter decomposition, and crop growth. The objective was to study the long-term (16-17 yr) influence of feedlot manure type and bedding on soil mesofauna over 2 yr (2014-2015). Stockpiled or composted feedlot manure with straw (ST) or wood-chip (WD) bedding (plus unamended control) was annually applied (13 Mg ha-1 dry wt.) to an irrigated clay loam soil with continuous barley (Hordeum vulgare L.). Intact cores were taken from surface (0-5 cm) soil in the fall, and the densities of Acari (mites) suborders and Collembola (springtails) families were determined. Manure type had no significant (P > 0.05) effect on soil mesofauna density. In contrast, there was a significant two- to sixfold increase in density with WD- compared with ST-amended soils of total Acari in 2014 and 2015, as well as total Collembola, total Acari and Collembola, oribatid mites, and entomobryid springtails in 2014. The bedding effect was attributed to significantly greater soil water content and lower bulk density for WD than ST. Density of soil mesofauna was not significantly greater in amended soils than in unamended soils. A shift by feedlot producers from stockpiled to composted feedlot manure application should have no effect on soil mesofauna density, whereas a shift from ST to WD bedding may increase the density of certain soil mesofauna, which may have a beneficial effect on soil. [ABSTRACT FROM AUTHOR]

Aim Lower limb amputation is a serious complication of diabetic foot disease and there are unexplained ethnic variations in incidence. This study investigates the risk of amputation among different ethnic groups after adjusting for demographic, socio-economic status and clinical variables. Methods We used primary care data from a large national multi-ethnic cohort of patients with Type 2 diabetes in New Zealand and linked hospital records. The primary outcome was time from initial data collection to first lower limb amputation. Demographic variables included age of onset and duration since diabetes diagnosis, gender, ethnicity and socio-economic status. Clinical variables included smoking status, height and weight, blood pressure, HbA1c, total cholesterol/HDL ratio and albuminuria. Cox proportional hazards models were used. Results There were 892 lower limb amputations recorded among 62 002 patients (2.11 amputations per 1000 personyears), followed for a median of 7.14 years (422 357 person-years). After adjusting for demographic and socio-economic variables and compared with Europeans, Maori had the highest risk [hazard ratio (HR) 1.84 (95% CI:1.54-2.19)], whereas East Asians [HR 0.18, (0.08-0.44)] and South Asians [HR 0.39 (0.22-0.67)] had the lowest risk. Adjusting for available clinical variables reduced the differences but they remained substantial [HR 1.61 (1.35-1.93), 0.23 (0.10-0.56) and 0.48 (0.27-0.83), respectively]. Conclusions Ethnic groups had significantly different risk of lower limb amputation, even after adjusting for demographic and some major clinical risk factors. Barriers to care should be addressed and intensive prevention strategies known to reduce the incidence of lower limb amputations could be prioritized to those at greatest risk. [ABSTRACT FROM AUTHOR]

Phosphorus (P) loss in tile drainage water may vary with agricultural practices, and t he impactsare often hard to detect with short-term studies. We evaluated the effects of long-term (≥43 yr) cropping systems (continuous corn [CC], corn-oats-alfalfa-alfalfa rotation [CR], and continuous grass [CS]) and fertilization (fertilization [F] vs. no-fertilization [NF]) on P loss in tile drainage water from a clay loam soil over a 4-yr period. Compared with NF, long-term fertilization increased concentrations and losses of dissolved reactive P (DRP), dissolved unreactive P (DURP), and total P (TP) in tile drainage water, with the increments following the order: CS > CR > CC. Dissolved P (dissolved reactive P [DRP] and dissolved unreactive P [DURP]) was the dominant P form in drainage outflow, accounting for 72% of TP loss under F-CS, whereas particulate P (PP) was the major form of TP loss under F-CC (72%), F-CR (62%), NF-CS (66%), NF-CC (74%), and NF-CR (72%). Dissolved unreactive P played nearly equal roles as DRP in P losses in tile drainage water. Stepwise regression analysis showed that the concentration of P (DRP, DURP, and PP) in tile drainage flow, rather than event flow volume, was the most important factor contributing to P loss in tile drainage water, although event flow volume was more important in PP loss than in dissolved P loss. Continuous grass significantly increased P loss by increasing P concentration and flow volume of tile drainage water, especially under the fertilization treatment. Long-term grasslands may become a significant P source in tile-drained systems when they receive regular P addition. [ABSTRACT FROM AUTHOR]

The long-term effect of land application of manure type (composted [CM] vs. stockpiled [SM] manure), bedding (wood-chips [WD] vs. straw [ST]), and application rate on yield, protein, fiber, and energy value of feed barley (Hordeum vulgare L.) for beef cattle (Bos taurus) is unknown. Dry matter yield and feed quality of irrigated feed barley was measured on a clay loam soil after 5 (2002), 8 (2005), and 12 yr (2009) of annual applications of CM or SM feedlot manure with WD or ST bedding at three application rates (13, 39, 77 Mg ha-1 dry wt.). The treatments also included an unamended control and inorganic fertilizer treatment. Mean yields in 2005 were significantly (P ≤ 0.05) greater for CM-ST than SM-WD but CM-ST was similar to SM-ST and CM-WD. Yields in 2009 were significantly lower for CM-WD compared to the other three treatments, and were greater for ST-13 and WD-77 compared to WD-13. Crude protein was greater for SM than CM when averaged over the 3 yr. Bedding influenced crude and soluble protein but the effects depended on interactions with rate and year. For example, crude and soluble protein in 2009 was greater for ST than WD at the 39 and 77 Mg ha-1 rates. Manure type and bedding may be practices to manage feed barley yield and protein, but will likely have little or no effect on the fiber content and energy value of the feed. [ABSTRACT FROM AUTHOR]

Excessive N loading from subsurface tile drainage has been linked to water quality degradation. Controlled tile drainage (CTD) has the potential to reduce N losses via tile drainage and boost crop yields. While CTD can reduce N loss from tile drainage, it may increase losses through other pathways. A multiple-year field-scale accounting of major N inputs and outputs during the cropping season was conducted on freely drained and controlled tile drained agricultural fields under corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] production systems in eastern Ontario, Canada. Greater predicted gaseous N emissions for corn and soybean and greater observed lateral seepage N losses were observed for corn and soybean fields under CTD relative to free-draining fields. However, observed N losses from tile were significantly lower for CTD fields, in relation to freely drained fields. Changes in residual soil N were essentially equivalent between drainage treatments, while mass balance residual terms were systematically negative (slightly more so for CTD). Increases in plant N uptake associated with CTD were observed, probably resulting in higher grain yields for corn and soybean. This study illustrates the benefits of CTD in decreasing subsurface tile drainage N losses and boosting crop yields, while demonstrating the potential for CTD to increase N losses via other pathways related to gaseous emissions and groundwater seepage. [ABSTRACT FROM AUTHOR]

Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Plantinga winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO3-) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO3- loss. Flow volume and NO3- concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO3- concentration in tile drainage water by 21 to 38% and cumulative NO3- loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO3- concentration by 15 to 33% and cumulative NO3- loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO3- concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L-1 and from 102 to 53.6 kg N ha-1) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO3- loss from cool, humid agricultural soils. [ABSTRACT FROM AUTHOR]

The environmental impact of using wood chips instead of straw bedding with feedlot manure on transport and leaching potential from feedlot manure is unknown. Our main objective was to determine if transport of total N, total organic N, NO3-N, and nonpurgeable organic C (NPOC) to subsurface soil was lower for soils amended with feedlot manure if combined with wood chips compared with straw. A secondary objective was to compare transport of N and NPOC with organic amendments versus inorganic fertilizer. Stockpiled feedlot manure (SM) with wood chip (SM-WD) or barley straw (SM-ST) bedding at 39 Mg (dry wt.) ha-1, and inorganic fertilizer (IN) at 100 kg N ha-1, was applied annually for 13 yr to a clay loam soil in a replicated field experiment in southern Alberta, Canada. Intact soil cores were taken in fall 2011 (0-30 cm depth) from the three treatments, and the residual N and NPOC were eluted from the soil cores. Total N, total organic N, and NPOC were determined on filtered (1.0 µm) effeluent samples that are primarily dissolved fraction but may contain some small particulate N and C. Peak concentrations, low-weighted mean concentrations, and mass loss of total N, total organic N, NO3-N, and NPOC were significantly (P = 0.05) lower by 35 to 86% for SM-WD compared with SM-ST. Mean recoveries were also significantly lower for SM-WD than SM-ST by 0.07 to 8% (absolute difference). The transport behavior was similar for SM-WD and IN treatment, but solute transport was greater for SM-ST than for IN. Application of stockpiled feedlot manure with wood chips instead of straw bedding may be a beneficial management practice to reduce transport and leaching potential of N fractions and NPOC. [ABSTRACT FROM AUTHOR]

The article discusses the study which examines the degree of soil phosphorus saturation based on Mehlich-3 P tests and soil water extractable phosphorus (P) in predicting runoff P loss from agricultural soils in Ontario. It implies that P loss in surface runoff from agricultural lands can contribute to eutrophication of surface water using rainfall simulation. The researchers have recommended soil DPS-3 as an indicator of dissolved reactive P concentration in surface runoff water due to its insensitive and simple soil pH.

The article discusses research that evaluated the effectiveness of controlled tile drainage and controlled tile drainage with subsurface irrigation for mitigating off-field nitrate losses and enhancing crop yields within agricultural lands enhanced by nitrogen fertilizers. These systems were compared upon a plot of clay loam soil to traditional unrestricted tile drainage upon which corn and soybeans were being rotated with varying nitrogen fertilization rates. Surface runoff and tile drainage were measured, as well as their impacts on aquatic life and water quality. Crop yields were also measured.

Aims To investigate the association between ethnicity and risk of first cardiovascular (CV) event for people with Type 2 diabetes in New Zealand. Methods A prospective cohort study using routinely collected data from a national primary health care diabetes annual review programme linked to national hospital admission and mortality data. Ethnicity was recorded as European, Maori, Pacific, Indo-Asian, East-Asian or Other. A Cox proportional hazards model was used to investigate factors associated with first CV event. Data was collected from 48 444 patients with Type 2 diabetes, with first data collected between 1 January 2000 and 20 December 2005, no previous cardiovascular event at entry and with complete measurements. Risk factors included ethnicity, gender, socio-economic status, body mass index, smoking, age at diagnosis, duration of diabetes, systolic blood pressure, serum lipids, glycated haemoglobin and urine albumin : creatinine ratio. The main outcome measures were time to first fatal or non-fatal CV event. Results Median follow-up was 2.4 years. Using combined European and Other ethnicities as a reference, hazard ratios for first CV event were 1.30 for Maori (95% confidence interval 1.19–1.41), 1.04 for Pacific (0.95–1.13), 1.06 for Indo-Asian (0.91–1.24) and 0.73 for East-Asian (0.62–0.85) after controlling for all other risk factors. Conclusions Ethnicity was independently associated with time to first CV event in people with Type 2 diabetes. Maori were at 30% higher risk of first CV event and East-Asian 27% lower risk compared with European/Other, with no significant difference in risk for Pacific and Indo-Asian peoples. [ABSTRACT FROM AUTHOR]

Aims To investigate the association between long-term glycaemic control, measured by glycated haemoglobin (HbA1c), and time to first cardiovascular disease (CVD) event for people with Type 2 diabetes in New Zealand. Methods A prospective cohort study including people with Type 2 diabetes but no previous CVD. The primary outcome measure was time to first recorded fatal or non-fatal CVD event (ischaemic heart disease, cerebrovascular accident, transient ischaemic attack or peripheral vascular disease) as identified from linked primary care, hospital and mortality records between January 2000 and December 2005. A Cox proportional hazards model was used to examine the association between HbA1c and time to CVD event, adjusting for age at diagnosis, duration of diabetes, gender, ethnicity, socio-economic status, smoking, blood pressure (BP), serum total cholesterol : high-density lipoprotein ratio, body mass index (BMI) and urine albumin : creatinine ratio. Results Participants included 48 444 people with Type 2 diabetes. Fifty-one per cent ( n = 24 721) were women, median age 60 years. Median duration of diabetes was 3 years, median BMI 31 kg/m2, median HbA1c 7.1% and mean BP was 138/81 mmHg. During the study period (median follow-up 2.4 years), there were 5667 first CVD events (11.7% of cohort). Each 1% increase in HbA1c was associated with an increase in hazard ratio (HR) for CVD of 1.08 (95% confidence interval 1.06–1.10, P < 0.001), myocardial infarction [HR 1.08 (1.04, 1.11)] and stroke [HR 1.09 (1.04, 1.13)]. Conclusion This study has confirmed in a large prospective cohort that increased HbA1c is an independent risk factor for cardiovascular disease after controlling for traditional risk factors. [ABSTRACT FROM AUTHOR]

Personnel assignment problems have traditionally been solved using operations research (OR) methods. The purpose of the research was to demonstrate the value of taking a systems view of personnel assignment beyond the usual OR models. Human factors methodologies and research methods were used to describe and analyze the components of the personnel assignment process at a printing company. These included macroergonomics, human–computer interaction, the skills–rules–knowledge (SRK) framework, hierarchical task analysis, decision ladders, and abstraction decomposition spaces. This approach facilitated assessments for function allocation and work system design, which are argued to be necessary for successful implementations of any solution for personnel assignment problems. © 2006 Wiley Periodicals, Inc. Hum Factors Man 16: 285–307, 2006. [ABSTRACT FROM AUTHOR]

Rainfall can transport herbicides from agricultural land to surface waters, where they become an environmental concern. Tile drainage can benefit crop production by removing excess soil water but tile drainage may also aggravate herbicide and nutrient movement into surface waters. Water management of tile drains after planting may reduce tile drainage and thereby reduce herbicide losses to surface water. To test this hypothesis we calculated the loss of three herbicides from a field with three water management systems: free drainage (D), controlled drainage (CD), and controlled drainage with subsurface irrigation (CDS). The effect of water management systems on the dissipation of atrazine (6‐chloro‐N2‐ethyl‐N4‐isopropyl‐1,3,5‐triazine‐2,4‐diamine), metribuzin [4‐amino‐6‐(1,1‐dimethylethyl)‐3‐(methylthio)‐1,2,4‐triazine‐5(4H)‐one), and metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐1‐methylethyl)acetamide] in soil was also monitored. Less herbicide was lost by surface runoff from the D and CD treatments than from CDS. The CDS treatment increased surface runoff, which transported more herbicide than that from D or CD treatments. In one year, the time for metribuzin residue to dissipate to half its initial value was shorter for CDS (33 d) than for D (43 d) and CD (46 d). The half‐life of atrazine and metolachlor were not affected by water management. Controlled drainage with subsurface irrigation may increase herbicide loss through increased surface runoff when excessive rain is received soon after herbicide application. However, increasing soil water content in CDS may decrease herbicide persistence, resulting in less residual herbicide available for aqueous transport. [ABSTRACT FROM AUTHOR]

SUMMARY Aim To examine the effects of improved glycaemic control over 20 weeks on the type and distribution of weight change in patients with type 2 diabetes who at baseline have poor glycaemic control. Methods Forty-three patients with type 2 diabetes and HbA1c > 8.9% were randomised to either intensive glycaemic control (IC) n = 21 or usual glycaemic control (UC) n = 22 for 20 weeks. Dual energy X-ray absorptiometry was used to assess the type and distribution of weight change during the study. Results After 20 weeks HbA1c was significantly lower in patients randomised to IC than UC (HbA1c IC 8.02 ± 0.25% vs. UC 10.23 ± 0.23%, p < 0.0001). In the IC group weight increased by 3.2 ± 0.8 kg after 20 weeks (fat-free mass increased by 1.8 ± 0.3 kg) compared to 0.02 ± 0.70 kg in UC (p = 0.003). The gain in total body fat mass comprised trunk fat mass (IC 0.94 ± 0.5 kg vs. UC 0.04 ± 0.4 kg, p = 0.18) and peripheral fat mass (total body fat – trunk fat) (IC 0.71 ± 0.32 kg vs. UC -0.21 ± 0.28 kg, p = 0.04). Blood pressure and serum lipid concentrations did not change over time in either group. Conclusions Intensive glycaemic control was associated with weight gain which was distributed in similar proportions between the central and peripheral regions and consisted of similar proportions of fat and fat-free mass. Blood pressure and serum lipid concentrations were not adversely affected. [ABSTRACT FROM AUTHOR]

The aim of this industrial study was to measure relationships between workstation ergonomics and product quality. Quality on two paced manual assembly lines for disposable cameras was measured by the number of defects per week at each workstation. Two ergonomic variables, the time required for the task and the postural deficiencies, were together able to predict over 50% of the quality variance on each assembly line. This study shows the direct effect of ergonomics variables on quality results. © 2001 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Atrazine (6‐chloro‐N2‐ethyl‐N4‐isopropyl‐1,3,5‐triazine‐2,4‐diamine) and metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐1‐methylethyl)acetamide] have been found with increasing occurrence in rivers and streams. Their continued use will require changes in agricultural practices. We compared water quality from four crop‐tillage treatments: (i) conventional moldboard plow (MB), (ii) MB with ryegrass (Lolium multiflorum Lam.) intercrop (IC), (iii) soil saver (SS), and (iv) SS + IC; and two drainage control treatments, drained (D) and controlled drainage–subirrigation (CDS). Atrazine (1.1 kg a.i. ha−1), metribuzin [4‐amino‐6‐(1,1‐dimethylethyl)‐3‐(methylthio)‐1,2,4‐triazine‐5(4H)‐one] (0.5 kg a.i. ha−1), and metolachlor (1.68 kg a.i. ha−1) were applied preemergence in a band over seeded corn (Zea mays L.) rows. Herbicide concentration and losses were monitored from 1992 to spring 1995. Annual herbicide losses ranged from <0.3 to 2.7% of application. Crop‐tillage treatment influenced herbicide loss in 1992 but not in 1993 or 1994, whereas CDS affected partitioning of losses in most years. In 1992, SS + IC reduced herbicide loss in tile drains and surface runoff by 46 to 49% compared with MB. The intercrop reduced surface runoff, which reduced herbicide transport. Controlled drainage–subirrigation increased herbicide loss in surface runoff but decreased loss through tile drainage so that total herbicide loss did not differ between drainage treatments. Des‐ethyl atrazine [6‐chloro‐N‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] comprised 7 to 39% of the total triazine loss. [ABSTRACT FROM AUTHOR]

Interactions between the quality movement and the human factors profession have been discussed in a number of recent papers. This article defines a basis for interaction based on the beliefs and techniques of both fields, and provides recent examples of cooperative efforts. Two specific challenges, one in manufacturing quality and one in service quality, are presented to demonstrate that human factors analyses of quality problems lead to new and useful insights. © 2000 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Ergonomics has traditionally focused on improving such indices as productivity, health and safety, and quality of work life. Such improvements are necessary to individuals and organizations, but may not be sufficient, as emphasized by the recent focus on community ergonomics and other “macrosystem” concerns. Ergonomists have begun to apply their technologies to go beyond traditional measures to impact regional economic development. A model for ergonomics in regional economic development was developed from a successful 10-year intervention in New York State. After presenting this model in terms of organizational design and core processes, two industrial cases are summarized to help validate the approach. Two large plants and industrial employers were threatened with closure. Macroergonomic assessment, research, and intervention led to significant job retention, facilities expansion, and job creation. Within 5 years, the approach was credited with several turnarounds, retaining and expanding thousands of jobs and transforming the regional economy. © 1999 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

With the demand for zero-defect products and the requirement of shorter lead-time production. designs of inspection systems have changed from using sampling inspection and human inspectors to 100% inspection and automated inspection systems. Unfortunately. automated inspection systems usually cannot meet the required performance without some human intervention. The objectives of this research are to demonstrate the feasibility of hybrid inspection systems, to compare these systems with the unaided human system and unaided automated inspection systems, and to develop a framework to allocate humans and computers in an inspection system in order to achieve the best system performance. This research found that a hybrid inspection system had better performance than either human inspection or entirely automated inspection systems. A proposed function allocation procedure was found to be feasible. [ABSTRACT FROM AUTHOR]

In order to provide aircraft maintenance and inspection personnel with a rapid means of locating the human–system mismatches that can lead to errors, two human factors audits were developed. Both the inspection audit and the maintenance audit are in the form of measurement checklists, usable either on a portable computer or in paper form. Both were tested for reliability and modified until high reliability was achieved. Both were validated against human factors professionals, with both programs identifying more mismatches than the practitioners. The programs are in use at an airline as a complement to existing safety and quality audit systems. © 1998 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

A study of the effects of increased levels of automation on the human operator illustrates the use of a computer-based approach to the use of verbal protocols as data in skill-based tasks, such as printed circuit board inspection. Subjects provided very detailed protocols at four automation levels, as well as generating performance and preference data. Although only one performance measure and one preference measure gave useful results, the use of verbal protocols provided many insights into the system-human interaction. Supplementing traditional performance measures with verbal protocols appears to be an appropriate strategy, even when the task is primarily at the skill level. © 1998 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Implemented change is the raison d'être of applied industrial human factors. Change is also recognized as a continuing process within industry, where processes such as continuous improvement and business process reengineering are used. Both in the broader industrial context and in ergonomic practice, the change process needs to be measurement driven. This article examines the relationships between the various levels of change in industry, using a control analogy. Measurement processes appropriate at different functional levels are derived, and illustrated with a case study of evaluating a corporate-wide ergonomics program. © 1997 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Airworthiness of the civil fleet is dependent upon the ability of inspectors to identify conditions for repair. As this is primarily a visual activity, the issue of training for visual inspection is critical. The inspection training literature has little detailed advice in this area, so in response to this need, a series of simulator experiments was undertaken for the development of improved training programs. This article briefly reviews each experiment and summarizes the results. Key conclusions drawn from each experiment are then used to demonstrate how they can be applied to enhance training for inspection tasks. © 1997 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

A model was developed to predict assembly time for a circuit board assembly task. It was based upon the GOMS language developed for task time prediction in human-computer interaction. It incorporated sequential elements of information processing, defined by cognitive, motor, and perceptual processors, in a critical path network. The model was used to predict assembly time for four assembly strategies using four different combinations of workstation and assembly sequences. The model was useful in predicting cognitive changes associated with the development of expertise. As assemblers gained experience, structural changes in the network implied that several processors were chunked. © 1997 John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Striking differences were found in the compartmentalization of fatty acids into liver lipid fractions. The saturated fatty acids-lauric, myristic, palmitic and stearic-were incorporated into phosphoglycerides at faster rates with increasing chain lengths, while triglyceride incorporation was almost uniform. The degree of incorporation of the unsaturated fatty acids into phosphoglycerides (structural) compared to triglyceride (storage and energy) was the converse of their oxidation rates. The incorporation of oleic, linoleic and α-linolenic acids was mainly into triglyceride, whereas dihomo-γ-linolenic acid and arachidonic acid were preferentially incorporated into phosphoglycerides. The data suggest that distribution of each fatty acid is different depending on its destination for structural or energy function. [ABSTRACT FROM AUTHOR]