Validation of water flux and body composition in Glaucous gulls (Larus hyperboreus)

Water influx rates (WIR) measured with tritiated water dilution were compared with direct measures of water and energy intake in glaucous gulls (Larus hyperboreus). Total body water (TBW) measured isotopically was also compared with TBW determined by body composition analysis (BCA) of the same birds. Seventeen wild gulls were captured and studied in outdoor enclosures at Ny-Ålesund, Svalbard, in July 2002. Gulls were hand-fed known quantities of Arctic cod (Boreogadus saida) or given water on the basis of one of four experimental treatments: (A) fasting, (B) fish only, (C) water only, or (D) fish and water. Water and energy content of Arctic cod was also determined. WIR of gulls (after subtracting metabolic water production) in treatments A, B, C, and D were 0, 101 ± 5, 62 ± 19, and 122 ± 21 SD g d-1, respectively. Measured water intake in each group was 0, 111 ± 2, 64 ± 3, and 134 ± 15 SD g d-1, respectively. On average, WIR underestimated measured water intake in each group. Errors were lowest but most variable for gulls fed water only (-2.2% ± 32.8%) compared with gulls fed fish only (-9.0% ± 5.4%) or fish and water (-9.0% ± 7.0%). Compared with measured water intake, errors in WIR were relatively low overall (-6.9% ± 17.4%) and comparable to previous validation studies. The difference in TBW determined by BCA versus isotopic dilution ranged between -1.02% and +8.59% of mass. On average, TBW measured isotopically (632 ± 24 g kg-1) overestimated true body water by a factor of 1.033

Modeling Socially Desirable Responding and Its Effects

The impact of socially desirable responding or faking on noncognitive assessments remains an issue of strong debate. One of the main reasons for the controversy is the lack of a statistical method to model such response sets. This article introduces a new way to model faking based on the assumption that faking occurs due to an interaction between person and situation. The technique combines a control group design with structural equation modeling and allows a separation of trait and faking variance. The model is introduced and tested in an example. The results confirm a causal nfluence of faking on means and covariance structure of a Big 5 questionnaire. Both effects can be reversed by the proposed model. Finally, a real-life criterion was implemented and predicted by both variance sources. In this example, it was the trait but not the faking variance that was predictive. Implications for research and practice are discussed

An update on the physiology of two- and three-toed sloths

Physiological and pharmacological research undertaken on sloths during the past 30 years is comprehensively reviewed. This includes the numerous studies carried out upon the respiratory and cardiovascular systems, anesthesia, blood chemistry, neuromuscular responses, the brain and spinal cord, vision, sleeping and waking, water balance and kidney function and reproduction. Similarities and differences between the physiology of sloths and that of other mammals are discussed in detail

ANÁLISE DO PADRÃO DE USO E COBERTURA DA TERRA ASSOCIADO AOS ASPECTOS GEOMORFOLÓGICOS NO MUNICÍPIO DE JUAZEIRO-BAHIA

O trabalho objetivou analisar a relação entre os aspetos geomorfológicos e o uso da cobertura da terra no município de Juazeiro-Bahia, para subsidiar a discussão sobre as potencialidades e restrições ambientais. Os dados sobre o relevo foram obtidos pelo processamento do MDT (MIRANDA, 2005), associados aos dados de uso e cobertura em ambiente SIG. Identificou-se que a agropecuária ocorre em áreas de baixa altitude, declividade e em função, inclusive, da existência da rede hidrográfica

Fast spin dynamics algorithms for classical spin systems

We have proposed new algorithms for the numerical integration of the equations of motion for classical spin systems. In close analogy to symplectic integrators for Hamiltonian equations of motion used in Molecular Dynamics these algorithms are based on the Suzuki-Trotter decomposition of exponential operators and unlike more commonly used algorithms exactly conserve spin length and, in special cases, energy. Using higher order decompositions we investigate integration schemes of up to fourth order and compare them to a well established fourth order predictor-corrector method. We demonstrate that these methods can be used with much larger time steps than the predictor-corrector method and thus may lead to a substantial speedup of computer simulations of the dynamical behavior of magnetic materials.Comment: 9 pages RevTeX with 8 figure

Evolution of body mass índex of women undergoing bariatric surgery in the pre- and pos-operative period: a retrospective study

[resumo][abstract

Sustainability considerations in membrane-based technologies for industrial effluents treatment

Treatment of industrial effluents (EFs) from the polluted wastewater sources using membrane technologies is an effective and attractive alternative to overcome the weaknesses of some of the conventional wastewater treatment processes, especially when dealing with EFs loaded with recalcitrant organic pollutants and toxic substances. The application of various polymeric and inorganic membrane based technologies to be used for the treatment of industrial EFs has attracted a considerable attention in the past decades. In this regard, a critical discussion on the sustainability of various aspects of membrane technologies would promote the commercialization of these technologies. In this review, various sustainability criteria in technical, economic, environmental, and social categories have been considered for a critical discussion on the current status and improvement opportunities of membrane technologies for the treatment of industrial EFs. While the application of polymeric membranes has been restricted by some bottlenecks to deal with some industrial effluents, metal oxides fabricated ceramic membranes, and especially those fabricated with nanostructured materials such as nano-zeolites, those made of metal organic frameworks as well as carbon-based fabricated membranes have shown a promising performance in the rejection of recalcitrant organic pollutants. In addition, the combinations of inorganic membrane technologies with other novel methods such as advanced oxidation processes (e.g., using engineered nanomaterials) can be considered among the best options to deal with such highly polluted effluents.publishe

Accelerometers can measure total and activity-specific energy expenditures in free-ranging marine mammals only if linked to time-activity budgets

Peer reviewedPostprin

Gravitomagnetic time-varying effects on the motion of a test particle

We study the effects of a time-varying gravitomagnetic field on the motion of test particles. Starting from recent results, we consider the gravitomagnetic field of a source whose spin angular momentum has a linearly time-varying magnitude. The acceleration due to such a time-varying gravitomagnetic field is considered as a perturbation of the Newtonian motion, and we explicitly evaluate the effects of this perturbation on the Keplerian elements of a closed orbit. The theoretical predictions are compared with actual astronomical and astrophysical scenarios, both in the solar system and in binary pulsars systems, in order to evaluate the impact of these effects on real systems.Comment: 8 pages, RevTeX; revised to match the version accepted for publication in General Relativity and Gravitatio