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Although dicamba-resistant crops can provide an effective weed management option, risk of dicamba off-site movement to sensitive crops is a concern. Previous research with indeterminate soybean identified 14 injury criteria associated with dicamba applied at V3/V4 or R1/R2 at 0.6 to 280 g ae ha−1. Injury criteria rated on a 0 to 5 scale (none to severe), along with percent visible injury and plant height reduction, and canopy height collected 7 and 15 d after treatment (DAT) were analyzed using multiple regression with a forward-selection procedure to develop yield prediction models. Variables included in the 15 DAT models (in order of selection) for V3/V4 were lower stem base lesions/cracking, plant height reduction, terminal leaf epinasty, leaf petiole droop, leaf petiole base swelling, and stem epinasty, whereas for R1/R2 variables were lower stem base lesions/cracking, terminal leaf chlorosis, leaf petiole base swelling, stem epinasty, terminal leaf necrosis, and terminal leaf cupping. To validate the models, experiments including the same dicamba rates and application timings used in previous research were conducted at two locations. For the variables specific to each model, data collected for the dicamba rates were used to predict yield. For the V3/V4 15 DAT model, predicted yield reduction (compared with the nontreated control for dicamba at 0.6 to 4.4 g ha−1) underestimated or overestimated observed yield reduction by an average of 1 and 3 percentage points. For 8.8 g ha−1, predicted yield reduction overestimated observed yield reduction by 8 points and for 17.5 g ha−1 by 20 points. For the R1/R2 15 DAT model, predicted yield reduction for 0.6 to 4.4 g ha−1 overestimated observed yield reduction by an average of 3 to 5 percentage points. For dicamba at 8.8 g ha−1, predicted yield reduction underestimated observed yield reduction by 8 points and for 17.5 g ha−1 overestimated by 6 points.
This study investigated the characteristics of subjective memory complaints (SMCs) and their association with current and future cognitive functions.
A cohort of 209 community-dwelling individuals without dementia aged 47–90 years old was recruited for this 3-year study. Participants underwent neuropsychological and clinical assessments annually. Participants were divided into SMCs and non-memory complainers (NMCs) using a single question at baseline and a memory complaints questionnaire following baseline, to evaluate differential patterns of complaints. In addition, comprehensive assessment of memory complaints was undertaken to evaluate whether severity and consistency of complaints differentially predicted cognitive function.
SMC and NMC individuals were significantly different on various features of SMCs. Greater overall severity (but not consistency) of complaints was significantly associated with current and future cognitive functioning.
SMC individuals present distinctive features of memory complaints as compared to NMCs. Further, the severity of complaints was a significant predictor of future cognition. However, SMC did not significantly predict change over time in this sample. These findings warrant further research into the specific features of SMCs that may portend subsequent neuropathological and cognitive changes when screening individuals at increased future risk of dementia.
Organizations are undergoing unprecedented transformation in the area of talent management (TM). Companies are rapidly adopting new tools and approaches in a variety of what has traditionally been core areas of industrial and organizational (I-O) psychology such as performance management, employee attitudes, recruiting, testing and assessment, and career development. Increasingly, however, these new approaches have little to no research backing behind them, and they do not tend to be the focus of I-O psychology theory and research. We call this trend anti-industrial and organizational psychology (AIO), as we believe these forces to do not advance the field for long-term strategic impact. We present a framework that describes how AIO practices are adopted by organizations, and how I-O psychologists often gravitate away from these practices rather than actively help to separate the wheat from the chaff. We found support for our hypothesis through a brief analysis of Industrial and Organizational Psychology: Perspectives on Science and Practice, the peer-reviewed journal of the Society of Industrial and Organizational Psychology (SIOP). In this analysis, we found that only 10% of the focal articles from 2008 to 2016 represented topics that we call frontier—emerging areas in organizations but where there is no research support for them. We propose a set of recommendations for the field of I-O psychology and call for a more strategic approach to identifying and vetting new TM trends in order to increase the relevancy and impact of I-O psychology for our key stakeholders.
To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case–control study among persons who use drugs. During June–October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case–control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1–51.9), IDU alone (aOR 52.7, CI 25.3–109.9), intranasal drug use alone (aOR 2.6, CI 1.8–3.9) and incarceration (aOR 2.7, CI 2.0–3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1–18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.
In the United States, cannabis accessibility has continued to rise as the perception of its harmfulness has decreased. Only about 30% of regular cannabis users develop cannabis use disorder (CUD), but it is unclear if individuals who use cannabis regularly without ever developing CUD experience notable psychosocial impairment across the lifespan. Therefore, psychosocial functioning was compared across regular cannabis users with or without CUD and a non-user control group during adolescence (age 17; early risk) and young adulthood (ages 18–25; peak CUD prevalence).
Weekly cannabis users with CUD (n = 311), weekly users without CUD (n = 111), and non-users (n = 996) were identified in the Minnesota Twin Family Study. Groups were compared on alcohol and illicit drug use, psychiatric problems, personality, and social functioning at age 17 and from ages 18 to 25. Self-reported cannabis use and problem use were independently verified using co-twin informant report.
In both adolescence and young adulthood, non-CUD users reported significantly higher levels of substance use problems and externalizing behaviors than non-users, but lower levels than CUD users. High agreement between self- and co-twin informant reports confirmed the validity of self-reported cannabis use problems.
Even in the absence of CUD, regular cannabis use was associated with psychosocial impairment in adolescence and young adulthood. However, regular users with CUD endorsed especially high psychiatric comorbidity and psychosocial impairment. The need for early prevention and intervention – regardless of CUD status – was highlighted by the presence of these patterns in adolescence.
This paper describes the design and fabrication of a range of ‘gas cell’ microtargets produced by the Target Fabrication Group in the Central Laser Facility (CLF) for academic access experiments on the Orion laser facility at the Atomic Weapons Establishment (AWE). The experiments were carried out by an academic consortium led by Imperial College London. The underlying target methodology was an evolution of a range of targets used for experiments on radiative shocks and involved the fabrication of a precision machined cell containing a number of apertures for interaction foils or diagnostic windows. The interior of the cell was gas-filled before laser irradiation. This paper details the assembly processes, thin film requirements and micro-machining processes needed to produce the targets. Also described is the implementation of a gas-fill system to produce targets that are filled to a pressure of 0.1–1 bar. The paper discusses the challenges that are posed by such a target.
In anticipation of the launch of the Earth Observing System (EOS) Terra, and the Aqua spacecraft in 1999 and 2000, respectively, efforts are ongoing to determine errors of satellite-derived snow-cover maps. EOS Moderate Resolution Imaging Spectrora-diometer (MODIS) and Advanced Microwave Scanning Radiometer-E (AMSR-E) snow-cover products will be produced. For this study we compare snow maps covering the same study areas in Canada and the United States, acquired from different sensors using different snow-mapping algorithms. Four locations are studied: (1) Saskatchewan, Canada; (2) New England (New Hampshire, Vermont and Massachusetts) and eastern New York; (3) central Idaho and western Montana; and (4) North and South Dakota. Snow maps were produced using a prototype MODIS snow-mapping algorithm from Landsat Thematic Mapper (TM) scenes of each study area at 30 m and when the TM data were degraded to 1 km resolution. U.S. National Operational Hydrologic Remote Sensing Center (NOHRSC) 1km resolution snow maps were also used, as were snow maps derived from 0.5° × 0.5° resolution Special Sensor Microwave Imager (SSM/I) data. A land-cover map derived from the International Geosphere-Biosphere Program land-cover map of North America was also registered to the scenes. The TM, NOHRSC and SSM/ I snow maps, and land-cover maps were compared digitally. In most cases, TM-derived maps show less snow cover than the NOHRSC and SSM/I maps because areas of incomplete snow cover in forests (e.g. tree canopies, branches and trunks) are seen in the TM data but not in the coarser-resolution maps which may map the areas as completely snow-covered. The snow maps generally agree with respect to the spatial variability of the snow cover. The 30 m resolutionTM data provide the most accurate snow maps, and are thus used as the baseline for comparison with the other maps. Results show that the changes in amount of snow cover, as compared to to the 30 m resolution TM maps, are lowest using the TM 1km resolution maps, at 0–40%. The greatest change (>100%) is found in the New England study area, probably due to the presence of patchy snow cover. A scene with patchy snow cover is more difficult to map accurately than is a scene with a well-defined snowline such as is found on the North and South Dakota scene where the changes were 0–40%. There are also some important differences in the amount of snow mapped using the two different SSM/I algorithms because they utilize different channels.
There are several hemispheric-scale satellite-derived snow-cover maps available, but none has been fully validated. For the period 23 October–25 December 2000, we compare snow maps of North America derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and operational snow maps from the U.S. National Oceanic and Atmospheric Administration (NOAA) National Operational Hydrologic Remote Sensing Center (NOHRSC), both of which rely on satellite data from the visible and near-infrared parts of the spectrum; we also compare MODIS maps with Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I) passive-microwave snow maps for the same period. The maps derived from visible and near-infrared data are more accurate for mapping snow cover than are the passive-microwave-derived maps, but discrepancies exist as to the location and extent of the snow cover even between operational snow maps. The MODIS snow-cover maps show more snow in each of the 8 day periods than do the NOHRSC maps, in part because MODIS maps the effects of fleeting snowstorms due to its frequent coverage. The large (~30 km) footprint of the SSM/I pixel, and the difficulty in distinguishing wet and shallow snow from wet or snow-free ground, reveal differences up to 5.33 x 106 km2 in the amount of snow mapped using MODIS vs SSM/I data. Algorithms that utilize both visible and passive-microwave data, which would take advantage of the all-weather mapping capability of the passive-microwave data, will be refined following the launch of the Advanced Microwave Scanning Radiometer (AMSR) in the fall of 2001.
Sea ice plays an important role in ocean–atmosphere heat exchange, global albedo and the marine ecosystem. Knowledge of variation in Sea-ice extent is essential in order to understand past climates, and to model possible future climate Scenarios. This paper presents results from a Short firn core Spanning 15 years collected from near Mount Brown, Wilhelm II Land, East Antarctica. Variations of methanesulphonic acid (MSA) at Mount Brown were positively correlated with Sea-ice extent from the coastal region Surrounding Mount Brown (60–120˚ E) and from around the entire Antarctic coast (0–360˚ E). Previous results from Law Dome identified this MSA–sea-ice relationship and proposed it as an Antarctic Sea-ice proxy (Curran and others, 2003), with the Strongest results found for the local Law Dome region. Our data provide Supporting evidence for the Law Dome proxy (at another Site in East Antarctica), but a deeper Mount Brown ice core is required to confirm the Sea-ice decline Suggested by Curran and others (2003). Results also indicate that this deeper record may also provide a more circum-Antarctic Sea-ice proxy.
We performed a spatial-temporal analysis to assess household risk factors for Ebola virus disease (Ebola) in a remote, severely-affected village. We defined a household as a family's shared living space and a case-household as a household with at least one resident who became a suspect, probable, or confirmed Ebola case from 1 August 2014 to 10 October 2014. We used Geographic Information System (GIS) software to calculate inter-household distances, performed space-time cluster analyses, and developed Generalized Estimating Equations (GEE). Village X consisted of 64 households; 42% of households became case-households over the observation period. Two significant space-time clusters occurred among households in the village; temporal effects outweighed spatial effects. GEE demonstrated that the odds of becoming a case-household increased by 4·0% for each additional person per household (P < 0·02) and 2·6% per day (P < 0·07). An increasing number of persons per household, and to a lesser extent, the passage of time after onset of the outbreak were risk factors for household Ebola acquisition, emphasizing the importance of prompt public health interventions that prioritize the most populated households. Using GIS with GEE can reveal complex spatial-temporal risk factors, which can inform prioritization of response activities in future outbreaks.
We have used the Cassegrain-focus Fourier Transform Spectrometer of the Canada-France-Hawaii Telescope to record high-resolution (0.03 cm−1), high signal-to-noise ratio spectra of the extreme carbon stars IRC+10°216 and CIT6 in the 2850–3100 cm−1 region. Upper limits were obtained for the column densities of silicon nitride (2-0 band of the A-X system), ethylene (ν11 fundamental band at ν0 = 2988.7 cm−1), and ethane (ν7 fundamental band at ν0 = 2985.4 cm−1).
The snow-pack on the Arctic Coastal Plain of Alaska has a well-developed depth-hoar layer which forms each year at the base of the snow-pack due to upward vapor transfer resulting from a temperature gradient in the snow-pack. The thickness of the depth-hoar layer tends to increase inland where greater temperature extremes (in particular, lower minimum temperatures) permit larger temperature gradients to develop within the snow-pack. Brightness temperature (TB) data were analyzed from October through May for four winters using the 37 GHz horizontally polarized Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR). By mid-winter each year, a decrease in TB of approximately 20K was found between coastal and inland sites on the Arctic Coastal Plain of Alaska. Modeling has indicated that a thicker depth-hoar layer in the inland sites could be responsible for the lower TBs. The large grain-sizes of the depth-hoar crystals scatter the upwelling radiation moreso than do smaller crystals, and greater scattering lowers the microwave TB. Using a two-layered radiative transfer model, the crystal diameter in the top layer was assumed to be 0.50 mm. The crystals in the depth-hoar layer may be 5–10 mm in diameter but the effective crystal diameter used in the radiative-transfer model is 1.40 mm. The crystal size used in the model had to be adjusted downward, relative to the actual crystal size, because the hollow, cup-shaped depth-hoar crystals are not as effective at scattering the microwave radiation as are spherical crystals that are assumed in the model. In the model, when the thickness of the depth-hoar layer was increased from 5 cm to 10 cm, a 21K decrease in TB resulted. This is comparable to the decrease in TB observed from coastal to inland sites in the study area.
In this study a new microwave snow retrieval algorithm was developed to account for the effects of atmospheric emission on microwave radiation over high-elevation land areas. This resulted in improved estimates of snow-covered area in western China when compared with the meteorological station data and with snow maps derived from visible imagery from the Defense Meteorological Satellite Program satellite. Some improvement in snow-depth estimation was also achieved, but a useful level of accuracy will require additional modifications tested against more extensive ground data.
During April 1995, a field and aircraft experiment was conducted in central Alaska in support of the Moderate Resolution Imaging Spectroradiometer (MODIS) snow-mapping project. The MODIS Airborne Simulator (MAS), a 50 channel spectroradiometer, was flown on board the NASA ER-2 aircraft. An objective of the mission was to determine the accuracy of mapping snow in different surface covers using an algorithm designed to map global snow cover after the launch of MODIS in 1998. The surface cover in this area of central Alaska is typically spruce, birch, aspen, mixed forest and muskeg. Integrated reflectance, Ri was calculated from the visible/near-infrared channels of the MAS sensor. The Ri was used to estimate different vegetation-cover densities because there is an inverse relationship between vegetation-cover density and albedo in snow-covered terrain. A vegetation-cover density map was constructed using MAS data acquired on 13 April 1995 over central Alaska. In the part of the scene that was mapped as having a vegetation-cover density of < 50%, the snow-mapping algorithm mapped 96.41% snow cover. These areas are generally composed of muskeg and mixed forests and include frozen lake. In the part of the scene that was estimated to have a vegetation-cover density of ≥50%, the snow-mapping algorithm mapped 71.23% snow cover. These areas are generally composed of dense coniferous or deciduous forests. Overall, the accuracy of the snow-mapping algorithm is > 87.41% for a 13 April MAS scene with a variety of surface covers (coniferous and deciduous and mixed forests, muskeg, tundra and frozen lake).
A Number of papers have been submitted to the International Congresses of Actuaries on the subject of life reassurance and full discussions have taken place at the Seventh, Eighth and Eleventh Congresses. Very little has been contributed to the Journal, and many years have elapsed since a paper was prepared on this subject.
GRS1915+105 is an extraordinary X-ray transient which exhibits superluminal radio jets. In this paper, ASCA observations of the GRS1915+105 conducted from 1994 to 1997 are reported. Observations are carried out on the following dates each for ~ 20 ksec exposure; Sep 27 1994, April 20 1995, Oct 23 1996 and Apr 25 1997.
The present study is the first record of twinning in Lagenorhynchus acutus and indeed any Lagenorhynchus sp. Both foetuses were male and located in the left uterine horn, had distinct grossly normal placentas and amniotic sacs, and were therefore likely dizygotic twins. The twins were an incidental finding in an animal that died of a systemic Brucella ceti infection.
The beef industry has emphasized the improvement of feed utilization, as measured by modeling feed intake through performance traits to calculate residual feed intake (RFI). Evidence supports an inverse relationship between feed efficiency and reproductive function. The objective of this study was to determine the relationship of reproductive assessments and RFI unadjusted (RFIKoch) or adjusted for body composition (RFIus) and the relationship among fertility-related parameters. In total, 34 crossbred bulls were housed together for 112 days of performance evaluation, followed by assessment of scrotum IR imaging, scrotal circumference, testes ultrasonography and semen quality parameters at 377±33.4 days of age. Bulls were slaughtered at 389±34.0 days of age, and analyses of carcass composition, biometrics and histomorphometry of the testis and epididymis were conducted. Bulls were grouped into two subpopulations based on divergence of RFI, and within each RFI model either by including 50% of the population (Halves, high and low RFI, n=17) or 20.6% extremes of the population (Tails, high and low RFI, n=7). The means of productive performance and fertility-related measures were compared through these categories. Pearson’s correlation was calculated among fertility-related measures. In the Halves subpopulation of the RFIus, sperm of low-RFI bulls had decreased progressive motility (47.30% v. 59.90%) and higher abundance of tail abnormalities (4.30% v. 1.80%) than that of high-RFI bulls. In the Tails subpopulation of the RFIKoch, low RFI displayed less variation in the scrotum surface temperature (0.62°C v. 1.16°C), decreased testis echogenicity (175.50 v 198.00 pixels) and larger (60.90 v. 56.80 mm2) but less-developed seminiferous tubules than high-RFI bulls. The evaluation of fertility-related parameters indicated that a higher percentage of immature seminiferous tubules was correlated with occurrence of sperm with distal droplets (r=0.59), a larger temperature variation at the top of the scrotum was correlated with improved sperm progressive motility (r=0.38), a lower occurrence of sperm loose head abnormalities was correlated with larger temperature variation at the lower part of the scrotum (r=−0.43), and a lower minimum testis echogenicity (r=−0.59) and smaller scrotal circumference (r=0.72) were correlated with age. The adjustment for body composition (RFI determination) enabled distinct biological inferences about reproduction and feed efficiency when compared with the non-adjusted model. However, both RFI models and the correlation analysis supported the hypothesis that feed-efficient bulls have features of delayed sexual maturity. Overall, the assessment of fertility-related measurements is important to avoid the improvement of feed efficiency at the expense of reproductive function in young bulls.