Residual Effects of N-K Fertilization of Coastal Bermudagrass on Spring Populations of Weed Species

A Coastal bermudagrass (Cynodon dactylon L.) sod was treated during a five-year period with rates of N and K fertilizers ranging from none to high levels of both elements. In the spring of the sixth year differences in weed species and population densities among the treated plots were observed. Spring weed counts showed that high rates of N fertilizer reduced the number of weed species and the total broadleaf weed population density by 37 and 81%, respectively. The higher rates of K fertilizer also reduced the population density of common dandelion (Taraxacum officinale Weber) and yellow toadflax (Linaria vulgaris Hill),the two dominant broadleaf weed species. The grass weed population, predominantly crabgrass (Digitaria sanguinalis ,L. Scop.) was not affected significantly by either N or K fertilizer levels

Data assurance in opaque computations

The chess endgame is increasingly being seen through the lens of, and therefore effectively defined by, a data ‘model’ of itself. It is vital that such models are clearly faithful to the reality they purport to represent. This paper examines that issue and systems engineering responses to it, using the chess endgame as the exemplar scenario. A structured survey has been carried out of the intrinsic challenges and complexity of creating endgame data by reviewing the past pattern of errors during work in progress, surfacing in publications and occurring after the data was generated. Specific measures are proposed to counter observed classes of error-risk, including a preliminary survey of techniques for using state-of-the-art verification tools to generate EGTs that are correct by construction. The approach may be applied generically beyond the game domain

The Antarctic Slope Current in a Changing Climate

The Antarctic Slope Current (ASC) is a coherent circulation feature that rings the Antarctic continental shelf and regulates the flow of water towards the Antarctic coastline. The structure and variability of the ASC influences key processes near the Antarctic coastline that have global implications, such as the melting of Antarctic ice shelves and water mass formation that determines the strength of the global overturning circulation. Recent theoretical, modeling, and observational advances have revealed new dynamical properties of the ASC, making it timely to review. Earlier reviews of the ASC focused largely on local classifications of water properties of the ASC's primary front. Here, we instead provide a classification of the current's frontal structure based on the dynamical mechanisms that govern both the along‐slope and cross‐slope circulation; these two modes of circulation are strongly coupled, similar to the Antarctic Circumpolar Current. Highly variable motions, such as dense overflows, tides, and eddies are shown to be critical components of cross‐slope and cross‐shelf exchange, but understanding of how the distribution and intensity of these processes will evolve in a changing climate remains poor due to observational and modeling limitations. Results linking the ASC to larger modes of climate variability, such as El Niño, show that the ASC is an integral part of global climate. An improved dynamical understanding of the ASC is still needed to accurately model and predict future Antarctic sea ice extent, the stability of the Antarctic ice sheets, and the Southern Ocean's contribution to the global carbon cycle

TWENTY-YEAR STATUS OF THE EASTERN MIGRATORY WHOOPING CRANE REINTRODUCTION

Since the 10-year status update in 2011, the first parent-reared whooping cranes (Grus americana) were released in the Eastern Migratory Population, the ultralight program (UL) ended, and cranes were released at new sites in eastern Wisconsin. During 2011-2020, 117 captive-reared whooping cranes were released; 75 costume-reared (35 in UL and 40 in the Direct Autumn Release program) and 42 parent-reared. There were no significant differences in 1- or 3-year survival rates based on rearing technique or release site. The population size remained at about 100 cranes during 2010-2018 but then decreased during 2018-2020 due to a reduced number of releases of captive-reared cranes and low recruitment. Predation remained the leading cause of death (54.1% of confirmed cases) for cases in which the cause of death could be determined, followed by impact trauma (18.8%), gunshot (10.5%), and disease (9.0%). The winter distribution shifted northward into more agricultural landscapes, with the majority of the population wintering in southern Indiana or northern Alabama. The summer distribution remained concentrated in Wisconsin, and breeding areas expanded into eastern Wisconsin. As a management response to nest abandonments caused by avian-feeding black flies (Simulium spp.), the first clutch of eggs was removed from nests at Necedah National Wildlife Refuge (i.e., forced renesting), which increased renesting rates from 42% to 79%. In total, 152 cranes were confirmed to have hatched in the wild, 27 of which survived to fledging. Two male whooping cranes nested with female sandhill cranes (Grus canadensis) and produced hybrid chicks. Three cranes were removed from the population due to using an active air strip on an Air National Guard base. As of April 2021, the estimated population size was 76 individuals (38 females, 36 males, and 2 of unknown sex), 16 of which were wild-hatched

Toward Common Data Elements for International Research in Long-term Care Homes: Advancing Person-Centered Care

To support person-centered, residential long-term care internationally, a consortium of researchers in medicine, nursing, behavioral, and social sciences from 21 geographically and economically diverse countries have launched the WE-THRIVE consortium to develop a common data infrastructure. WE-THRIVE aims to identify measurement domains that are internationally relevant, including in low-, middle-, and high-income countries, prioritize concepts to operationalize domains, and specify a set of data elements to measure concepts that can be used across studies for data sharing and comparisons. This article reports findings from consortium meetings at the 2016 meeting of the Gerontological Society of America and the 2017 meeting of the International Association of Gerontology and Geriatrics, to identify domains and prioritize concepts, following best practices to identify common data elements (CDEs) that were developed through the US National Institutes of Health/National Institute of Nursing Research's CDEs initiative. Four domains were identified, including organizational context, workforce and staffing, person-centered care, and care outcomes. Using a nominal group process, WE-THRIVE prioritized 21 concepts across the 4 domains. Several concepts showed similarity to existing measurement structures, whereas others differed. Conceptual similarity (convergence; eg, concepts in the care outcomes domain of functional level and harm-free care) provides further support of the critical foundational work in LTC measurement endorsed and implemented by regulatory bodies. Different concepts (divergence; eg, concepts in the person-centered care domain of knowing the person and what matters most to the person) highlights current gaps in measurement efforts and is consistent with WE-THRIVE's focus on supporting resilience and thriving for residents, family, and staff. In alignment with the World Health Organization's call for comparative measurement work for health systems change, WE-THRIVE's work to date highlights the benefits of engaging with diverse LTC researchers, including those in low-, middle-, and high-income countries, to develop a measurement infrastructure that integrates the aspirations of person-centered LTC

The importance of interocean exchange south of Africa in a numerical model

A fine resolution numerical model of the Southern Ocean (the Fine Resolution Antarctic Model (FRAM)) has been used to investigate the way in which heat is supplied to the South Atlantic. The heat budget in the model is compared with other estimates and is found to be broadly realistic. The temperature structure in the Atlantic, and therefore the meridional heat transport, depend heavily on the input of heat from the Indian Ocean via the Agulhas Retroflection region. FRAM is compared with three models which do not exhibit a significant input of heat from the Indian Ocean. These models also have a lower equatorward heat transport in the South Atlantic. Horizontal resolution affects the amount of Agulhas transfer with coarser resolution leading to lower heat transport in the Atlantic, a result which has implications for ocean models used in climate simulations

SANS polarization analysis with nuclear-spin-polarized He-3

A neutron spin filter based on transmission through nuclear-spin-polarized He-3 gas has been applied to polarization analysis of small angle neutron scattering (SANS). Such spin filters, which are based on the large spin dependence of the absorption of neutrons by He-3, make SANS polarization analysis possible because of their large angular acceptance. In the present experiment, a He-3-based analyzer was employed to separate nuclear scattering into its coherent and spin-incoherent components. Polarized He-3 analyzers were prepared by two different optical pumping methods and installed on the NG3 SANS instrument at the NIST Center for Neutron Research (NCNR). Measurements were taken on cellophane tape and silica gel, for which the scattering is almost completely incoherent and coherent, respectively, and on a combined sample. For the combined sample, separation of the coherent part from the incoherent part was successfully demonstrated using polarization analysis