Search results for " America."
showing 10 items of 686 documents
Data from: Moving in the Anthropocene: global reductions in terrestrial mammalian movements
2019
Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects no…
Rapid determination of pharmaceuticals in wastewater by direct infusion HRMS using target and suspect screening analysis
2021
Abstract A wide-scope screening of active pharmaceutical ingredients (APIs) and their transformation products (TPs) in wastewater can yield valuable insights and pinpoint emerging contaminants that have not been previously reported. Such information is relevant to investigate their occurrence and fate in various environmental compartments. In this study, we explored the applicability of direct infusion high resolution mass spectrometry (DI-HRMS) for comprehensive and rapid detection of APIs and their TPs in wastewater samples. The method was developed using a Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) system and incorporated both wide-scope suspect screening and…
Uncinaria hamiltoni (Nematoda: Ancylostomatidae) in South American Sea Lions, Otaria flavescens, From Northern Patagonia, Argentina
2004
Thirty-one South American sea lion pups (Otaria flavescens) found dead in Punta León, Argentina, during the summer of 2002, were examined for hookworms (Uncinaria hamiltoni). Parasite parameters were analyzed in 2 locations of the rookery, i.e., a traditional, well-structured breeding area and an expanding area with juveniles and a lax social structure. Prevalence of hookworms was 50% in both localities, and no difference was observed in prevalence between pup sexes (P > 0.05). Hookworms were concentrated in the small intestine. Transmammary transmission is assumed because only adult hookworms were found in the pups. The mean intensity of hookworms per pup was 135; the mean intensity in fem…
Molecular mechanisms of hookworm disease: stealth, virulence, and vaccines.
2012
Hookworms produce a vast repertoire of structurally and functionally diverse molecules that mediate their long-term survival and pathogenesis within a human host. Many of these molecules are secreted by the parasite, after which they interact with critical components of host biology, including processes that are key to host survival. The most important of these interactions is the hookworm's interruption of nutrient acquisition by the host through its ingestion and digestion of host blood. This results in iron deficiency and eventually the microcytic hypochromic anemia or iron deficiency anemia that is the clinical hallmark of hookworm infection. Other molecular mechanisms of hookworm infec…
Présence d’Asellides stygobies (Crustacea, Isopoda, Aselloidea) dans la région du Primorye, Sibérie sud-orientale
1993
Two species of anophthalmous, unpigmentedasellids have been found in springs and groundwaters of S.E. Siberia (Primorye region). Asellus (Asellus) primoryensis n. sp. is closelyrelated to the epigean species A. (A.) hilgendorfii Bovallius, 1886, as is the case for all stygobiont Asellus (Asellus) species previously known from the Japanese archipelago. Sibirasellus parpurae n. g., n. sp. is closely related to the microphthalmous species Asellus dentifer Birstein & Levanidov, 1952 from the Ussuri Basin (Khor region), now type-species of the new genus Sibirasellus. These two species show several original characters: body covered by numerous cuticular squamulae, mandibular palp reduced (gla…
Determinants and efficiency of Pakistan's chemical products' exports: An application of stochastic frontier gravity model.
2019
The estimation of efficiency of industry-specific exports is very important to find exports' gap and to frame exports promotion policy for targeted industry. This study attempts to investigate the main determinants of chemical products' exports of Pakistan with 62 trading partners by applying Stochastic Frontier Analysis (SFA) on an augmented gravity model for a period 1995-2015. The results corroborate that chemical products' exports follow gravity patterns. This study finds a negative and significant impact of import tariff on exports of chemical products while the positive impact of devaluation has been observed. Further, the estimations also take into account the impact of Preferential …
Bayesian dynamic modeling of time series of dengue disease case counts
2017
The aim of this study is to model the association between weekly time series of dengue case counts and meteorological variables, in a high-incidence city of Colombia, applying Bayesian hierarchical dynamic generalized linear models over the period January 2008 to August 2015. Additionally, we evaluate the model’s short-term performance for predicting dengue cases. The methodology shows dynamic Poisson log link models including constant or time-varying coefficients for the meteorological variables. Calendar effects were modeled using constant or first- or second-order random walk time-varying coefficients. The meteorological variables were modeled using constant coefficients and first-order …
Multiple aspects of plasticity in clutch size vary among populations of a globally-distributed songbird.
2013
Plasticity in life-history characteristics can influence many ecological and evolutionary phenomena, including how invading organisms cope with novel conditions in new locations or how environmental change affects organisms in native locations. Variation in reaction norm attributes is a critical element to understanding plasticity in life history, yet we know relatively little about the ways in which reaction norms vary within and among populations. We amassed data on clutch size from marked females in eight populations of house sparrows (Passer domesticus) from North America and Europe. We exploited repeated measures of clutch size to assess both the extent of within-individual phenotypic …
Avocado “born in Sicily”, gli agricoltori scommettono su questa produzione
2021
In questo lavoro è stato possibile mettere a confronto la qualità dei frutti di avocado Born in Sicily e di quelli Imported. I risultati ottenuti evidenziano per i frutti raccolti in Sicilia valori più elevati del contenuto di sostanza grassa, di alcune vitamine e minerali rispetto a quelli importati, indicando nell’avocado isolano un frutto ricco di componenti dall’alto valore nutrizionale.
Genetic variability of Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) populations from Latin America is associated with variations in susceptib…
2006
ABSTRACT Bacillus thuringiensis strains isolated from Latin American soil samples that showed toxicity against three Spodoptera frugiperda populations from different geographical areas (Mexico, Colombia, and Brazil) were characterized on the basis of their insecticidal activity, crystal morphology, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of parasporal crystals, plasmid profiles, and cry gene content. We found that the different S. frugiperda populations display different susceptibilities to the selected B. thuringiensis strains and also to pure preparations of Cry1B, Cry1C, and Cry1D toxins. Binding assays performed with pure toxin demonstrated that the differences in the …