7,247 research outputs found
An Analysis of the Interactions Between Weather and Land Use on Midwestern Gamebird Populations Using Historical Data: A Preliminary Report
Concern surrounding species’ abilities to cope with a changing climate and variable land use presents opportunities to look forward toward solutions while investigating historical trends to assess the interaction of land use and weather. Uncertainty surrounding population responses to increased severity and frequency of severe weather associated with climate change presents challenges for making informed management decisions for a suite of already declining bird populations, including huntable populations of socially and economically important game birds, such as northern bobwhite (Colinus virginianus). Historical data are a rich resource for developing a priori hypotheses and models predicting species’ responses to climate change and continued variation in land use. We are utilizing 30 years of historical data to model the responses of northern, ring-necked pheasant (Phasianus colchicus), and wild turkey (Meleagris gallopavo) to land use change and weather within a gradient of land use and climate in Nebraska, Kansas, Iowa, and Missouri. Mixed models incorporating agricultural acreages, relative abundances of gallinaceous birds from the annual Breeding Bird Survey, and historical precipitation and temperature data built at the county-level will illuminate broad scale trends and enable us to draw conclusions about future population responses. We are finding expected differences in population trends between states within a climatic gradient, and varied responses to temperature and precipitation among gallinaceous species, where different annual periods are more or less crucial for different species despite similar life history characteristics. We expect that further modeling will continue to elucidate critical thresholds for birds in the Great Plains in terms of weather and habitat, allowing us to make strong recommendations to managers preparing to deal with the implications of climate change
Life cycle of hake and likely management implications
-Despite its economic and social importance for Namibia and South Africa, limited documented information exists regarding key aspects of the biology of deep-water hake, including its life cycle. This study utilizes data collected through the demersal surveys of the R/V Dr Fridtjof Nansen in South Africa and F/V Blue Sea 1 in Namibia to describe the migratory patterns of deep-water hake in space and time. Furthermore the study investigates aspects of the life cycle of this important species in the Benguela region. Results show that deep-water hake spawns between the western Agulhas Bank and Elands Bay in South Africa with the main nursery ground between Hondeklip Bay and the northern tip of Orange Banks. Deep-water hake in Namibia (up to the Kunene River) and along the south coast of South Africa (eastwards to Port Alfred) originate from these grounds, and undertake long-range migrations across latitudes and longitudes, respectively. This hypothesis is supported by the finding that spawning has not been observed in Namibia and there are no small juveniles along the South African south coast from the eastern border of the Agulhas Bank. The proposed pattern implies an interconnection between the Namibian and the South African components of the stock and the consequent need for a revision of the present management regime based on the assumption of stocks confined within the respective national jurisdictions. This study has used length frequency distributions in space and time in order to investigate the life cycle, in terms of origin, movement and population structure in particular, an approach that may also be useful for other widely distributed species
Cwatset Isomorphism and its Consequences
We explore the consequences of cwatset isomorphism (there are a finite number of non-isomorphic cwatsets of each order) and consider parallels between the theory of groups and the theory of cwatsets (cwatsets of prime order are cyclic but direct sums of isomorphic cwatsets aren\u27t necessarily isomorphic)
Using P-band Signals of Opportunity Radio Waves for Root Zone Soil Moisture Remote Sensing
Retrieval of Root Zone Soil Moisture (RZSM) is important for understanding the carbon cycle for use in climate change research as well as meteorology, hydrology, and precision agriculture studies. A current method of remote sensing, GNSS-R uses GPS signals to measure soil moisture content and vegetation biomass, but it is limited to 3-5 cm of soil penetration depth. Signals of Opportunity (SoOp) has emerged as an extension of GNSS-R remote sensing using communication signals. P-band communication signals (370 MHz) will be studied as an improved method of remote sensing of RZSM. P-band offers numerous advantages over GNSS-R, including stronger signal strength and deeper soil penetration. A SoOp instrument was installed on a mobile antenna tower in a farm field at Purdue University in West Lafayette, IN. An additional half-wave dipole antenna, as well as corresponding modifications to the experiment’s front-end box, was included to capture horizontally-polarized reflected P-band signals throughout a corn growth season. By measuring the reflected signal power off the soil over time, soil moisture and above-ground biomass can be measured. Soil moisture and vegetation biomass change the soil’s dielectric reflection coefficient and thus affect its reflectivity properties. It is expected that there will be strong correlation between reflected signal strength and soil moisture. Data will be compared against soil moisture measurements from in-situ soil sensors. The data obtained will be used to verify existing analytical soil moisture and above-ground biomass models. In addition, these results will be used to build an airborne and/or space-based remote sensing instrument
Cartography interpreted of soil : San Carlos, Mendoza (Argentina)
El objetivo del trabajo fue generar mapas y asociarlos a bases de datos digitales donde se puedan consultar, en forma automatizada y eficiente, preguntas temáticas y por localización. No importa la cartografía en sí misma, sino el análisis, la interpretación y el establecimiento de indicadores de aptitudes edáficas a partir de información geográfica sistematizada. La Información básica es confiable y posee la máxima integridad. Con IDRISI se realizó, con las bandas 5, 4 Y 3 una composición en falso color. Se elaboraron mapas digitalizados de clasificación no supervisada de cobertura del suelo. Se confeccionó, en Access, una base de datos con 26 registros de determinaciones edáficas. Se exportó esta información temática a IDRISI versión 2.0. Con IDRISI se cartografiaron diferentes campos de la base de datos, lo que estableció distintas zonas pilotos en las que se realizó análisis espacial. De estos análisis se crearon mapas temáticos en formato digital. Con otra base de datos reales de 20 registros se convalidaron los resultados de las cartografías realizadas.
El trabajo expresa una visión general real de las características edáficas superficiales más importantes y las cartografías cas realizadas tienen valor práctico al establecer indicadores que sirven para quienes tengan conocimientos edafológicos medios.The objective of the work is to generate maps and to associate them to digital databases. Where the databas es are immediately available and thematic and localization questions can be consulted in automated, efficient and effective formo The basis is not only the cartography by itself but also to analyse, to interpret, to create knowledge, to set indicators of edaphic aptitudes, starting from the data and systematized geographical information. The basic information is reliable and it possesses the maximum integrity. With IDRISI a composition in false color, with the bands 5, 4 and 3 was carried out. Digitized maps of not supervised classification of covering of the soil were elaborated. In Access a database with 26 registrations of edaphic determinations was created. Thematic information was exported to IDRIS1 version 2:0. In IDRISI different fields of the database were established different control areas in those that space analyses was carried out. From these analyses thematic maps were created in digital formato With another database of 20 registrations, the results of temáti¬ the carried out cartographies was authenticated.
The work expresses a general vision of the most important characteristic of surface soil and the thematic cartographies carried out have an important practical value, specially for those who have average edaphic knowledge.Fil: Perez Valenzuela, Benjamín R..
Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: De Cara, Daniel E. .
Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Lipinski, Víctor M. .
Universidad Nacional de Cuyo. Facultad de Ciencias Agraria
Serendipitous Discovery of Light-Induced \u3cem\u3e(In Situ)\u3c/em\u3e Formation of An Azo-Bridged Dimeric Sulfonated Naphthol as a Potent PTP1B Inhibito
Background Protein tyrosine phosphatases (PTPs) like dual specificity phosphatase 5 (DUSP5) and protein tyrosine phosphatase 1B (PTP1B) are drug targets for diseases that include cancer, diabetes, and vascular disorders such as hemangiomas. The PTPs are also known to be notoriously difficult targets for designing inihibitors that become viable drug leads. Therefore, the pipeline for approved drugs in this class is minimal. Furthermore, drug screening for targets like PTPs often produce false positive and false negative results. Results Studies presented herein provide important insights into: (a) how to detect such artifacts, (b) the importance of compound re-synthesis and verification, and (c) how in situ chemical reactivity of compounds, when diagnosed and characterized, can actually lead to serendipitous discovery of valuable new lead molecules. Initial docking of compounds from the National Cancer Institute (NCI), followed by experimental testing in enzyme inhibition assays, identified an inhibitor of DUSP5. Subsequent control experiments revealed that this compound demonstrated time-dependent inhibition, and also a time-dependent change in color of the inhibitor that correlated with potency of inhibition. In addition, the compound activity varied depending on vendor source. We hypothesized, and then confirmed by synthesis of the compound, that the actual inhibitor of DUSP5 was a dimeric form of the original inhibitor compound, formed upon exposure to light and oxygen. This compound has an IC50 of 36 μM for DUSP5, and is a competitive inhibitor. Testing against PTP1B, for selectivity, demonstrated the dimeric compound was actually a more potent inhibitor of PTP1B, with an IC50 of 2.1 μM. The compound, an azo-bridged dimer of sulfonated naphthol rings, resembles previously reported PTP inhibitors, but with 18-fold selectivity for PTP1B versus DUSP5. Conclusion We report the identification of a potent PTP1B inhibitor that was initially identified in a screen for DUSP5, implying common mechanism of inhibitory action for these scaffolds
Sperm storage and mating in the deep-sea squid Taningia danae Joubin, 1931 (Oegopsida:Octopoteuthidae)
Spermatangium implantation is reported in the large oceanic squid Taningia danae, based on ten mated females from the stomachs of sperm whales. Implanted spermatangia were located in the mantle, head and neck (on both sides) or above the nuchal cartilage, under the neck collar and were often associated with incisions. These cuts ranged from 30 to 65 mm in length and were probably made by males, using the beak or arm hooks. This is the first time wounds facilitating spermatangium storage have been observed in the internal muscle layers (rather than external, as observed in some other species of squid). The implications of these observations for the mating behavior of the rarely encountered squid T. danae are discussed
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Experimental evidence on promotion of electric and improved biomass cookstoves.
Improved cookstoves (ICS) can deliver "triple wins" by improving household health, local environments, and global climate. Yet their potential is in doubt because of low and slow diffusion, likely because of constraints imposed by differences in culture, geography, institutions, and missing markets. We offer insights about this challenge based on a multiyear, multiphase study with nearly 1,000 households in the Indian Himalayas. In phase I, we combined desk reviews, simulations, and focus groups to diagnose barriers to ICS adoption. In phase II, we implemented a set of pilots to simulate a mature market and designed an intervention that upgraded the supply chain (combining marketing and home delivery), provided rebates and financing to lower income and liquidity constraints, and allowed households a choice among ICS. In phase III, we used findings from these pilots to implement a field experiment to rigorously test whether this combination of upgraded supply and demand promotion stimulates adoption. The experiment showed that, compared with zero purchase in control villages, over half of intervention households bought an ICS, although demand was highly price-sensitive. Demand was at least twice as high for electric stoves relative to biomass ICS. Even among households that received a negligible price discount, the upgraded supply chain alone induced a 28 percentage-point increase in ICS ownership. Although the bundled intervention is resource-intensive, the full costs are lower than the social benefits of ICS promotion. Our findings suggest that market analysis, robust supply chains, and price discounts are critical for ICS diffusion
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The Tabby cat locus maps to feline chromosome B1.
The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (Ta-) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, theta = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17-cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats
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