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Passive Behaviors (passive + behavior)
Selected AbstractsA Taxonomy of Passive Behaviors in People with Alzheimer's DiseaseJOURNAL OF NURSING SCHOLARSHIP, Issue 3 2000Kathleen Byrne Colling Purpose: To construct a taxonomy of passive behaviors for understanding people with Alzheimer's disease. Passive behaviors are those associated with decreased motor movements, decreasing interactions with the environment, and feelings of apathy and listlessness. Little is known about behaviors associated with passivity, and these behaviors have not been categorized. Organizing Construct: Taxonomy construction. Passive behaviors in people with Alzheimer's disease were conceptualized as disturbing behaviors, patterns of personality change, and negative symptoms. Methods: The taxonomy was developed using critical reviews of 15 empirical studies published 1985 through 1998. Procedures included listing behaviors; clustering behaviors into inductively derived groupings; conducting an expert panel-review, making revisions, and conduting a second review; establishing global and category-by-category reliability using Cohen's Kappa. Findings: The nonhierarchic, natural taxonomy indicated five categories of behaviors associated with passivity in Alzheimer's disease: diminutions of cognition, psychomotor activity, emotions, interactions with people, and interactions with the environment. Analysis indicated substantial agreement beyond chance and showed statistically significant agreement among the six nurse-expert raters. Areas of synchrony between the taxonomy and the Need-Driven Dementia Compromised Behavior Model were identified. Conclusions: This taxonomy of passive behaviors in patients with Alzheimer's disease showed empirical rigor and compatibility with a middle-range theory and can be viewed as a sensitizing analytic scheme to guide future practice, research, and theory development. [source] In vivo acute toxicity of titanium dioxide nanoparticles to mice after intraperitioneal injectionJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2009Jinyuan Chen Abstract Because of its excellent optical performance and electrical properties, TiO2 has a wide range of applications in many fields. It is often considered to be physiologically inert to humans. However, some recent studies have reported that nano-sized TiO2 may generate potential harm to the environment and humans. In this paper the in vivo acute toxicity of nano-sized TiO2 particles to adult mice was investigated. Mice were injected with different dosages of nano-sized TiO2 (0, 324, 648, 972, 1296, 1944 or 2592 mg kg,1). The effects of particles on serum biochemical levels were evaluated at various time points (24 h, 48 h, 7 days and 14 days). Tissues (spleen, heart, lung, kidney and liver) were collected for titanium content analysis and histopathological examination. Treated mice showed signs of acute toxicity such as passive behavior, loss of appetite, tremor and lethargy. Slightly elevated levels of the enzymes alanine aminotransferase and aspartate aminotransferase were found from the biochemical tests of serum whereas blood urea nitrogen was not significantly affected (P <0.05). The accumulation of TiO2 was highest in spleen (P <0.05). TiO2 was also deposited in liver, kidney and lung. Histopathological examinations showed that some TiO2 particles had entered the spleen and caused the lesion of spleen. Thrombosis was found in the pulmonary vascular system, which could be induced by the blocking of blood vessels with TiO2 particles. Moreover, hepatocellular necrosis and apoptosis, hepatic fibrosis, renal glomerulus swelling and interstitial pneumonia associated with alveolar septal thickening were also observed in high-dose groups. Copyright © 2009 John Wiley & Sons, Ltd. [source] Effects of Hf content and immersion time on electrochemical behavior of biomedical Ti-22Nb- xHf alloys in 0.9% NaCl solutionMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 5 2009B. L. Wang Abstract The aim of this study was to investigate the effects of Hf content and immersion time on the electrochemical corrosion behavior of the Ti-22Nb- xHf (x,=,0, 2, 4, and 6 at%) alloy samples in 0.9% NaCl solution at 37,°C and neutral pH range, utilizing the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. From the polarization curves, all these alloys exhibited typical passive behavior, which was indicated by a wide passive region without the breakdown of the passive films and low corrosion current densities. In addition, the values of the corrosion current densities and passive current densities decreased with increase in the Hf content. The EIS results, fitted by RS(QPRP) model, exhibited capacitive behavior (high corrosion resistance) with phase angles closed to ,80° and high impedance values at low and medium frequencies, indicating the formation of a highly stable film on these alloys in the test solution. The resistance of the passive films improved with increase in the Hf content and immersion time. All these observations suggested a more noble electrochemical behavior of the Ti-22Nb- xHf alloys compared to the Ti-Nb binary alloy. [source] Alpha-melanocyte-stimulating hormone attenuates behavioral effects of corticotropin-releasing factor in isolated guinea pig pupsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 5 2009Patricia A. Schiml-Webb Abstract During a 3-hr period of social isolation in a novel environment, guinea pig pups exhibit an initial active phase of behavioral responsiveness, characterized primarily by vocalizing, which is then followed by a stage of passive responsiveness in which pups display a distinctive crouch, eye-closing, and extensive piloerection. Prior treatment of pups with alpha-melanocyte-stimulating hormone (,-MSH) reduces each of the passive behaviors. The onset of passive responding during separation can be accelerated with peripheral injection of corticotropin-releasing factor (CRF). To examine whether CRF produces its effects through a mechanism similar to that of prolonged separation, we examined the effect of administering ,-MSH to pups injected with CRF. As expected, CRF markedly enhanced passive responding during a 60-min period of separation. ,-MSH delivered by either intracerebroventricular infusion or intraperitoneal injection significantly reduced each of the passive behavioral responses without significantly affecting active behavior. These findings, together with previous results indicating that it is the anti-inflammatory property of ,-MSH that is responsible for its behavioral effects during prolonged separation, suggest that peripheral CRF speeds the induction of passive responding through a mechanism involving enhanced proinflammatory activity. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 399,407, 2009. [source] Active and passive behaviors of soft tissues: Pelvic floor musclesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 6 2010M. P. M. Pato Abstract A new active-contraction visco-elastic numerical model of the pelvic floor (skeletal) muscle is presented. Our model includes all elements that represent the muscle constitutive behavior, contraction and relaxation. In contrast with the previous models, the activation function can be null. The complete equations are shown and exactly linearized. Small verification and validation tests are performed and the pelvis is modeled using the data from the intra-abdominal pressure tests. Copyright © 2009 John Wiley & Sons, Ltd. [source] A Taxonomy of Passive Behaviors in People with Alzheimer's DiseaseJOURNAL OF NURSING SCHOLARSHIP, Issue 3 2000Kathleen Byrne Colling Purpose: To construct a taxonomy of passive behaviors for understanding people with Alzheimer's disease. Passive behaviors are those associated with decreased motor movements, decreasing interactions with the environment, and feelings of apathy and listlessness. Little is known about behaviors associated with passivity, and these behaviors have not been categorized. Organizing Construct: Taxonomy construction. Passive behaviors in people with Alzheimer's disease were conceptualized as disturbing behaviors, patterns of personality change, and negative symptoms. Methods: The taxonomy was developed using critical reviews of 15 empirical studies published 1985 through 1998. Procedures included listing behaviors; clustering behaviors into inductively derived groupings; conducting an expert panel-review, making revisions, and conduting a second review; establishing global and category-by-category reliability using Cohen's Kappa. Findings: The nonhierarchic, natural taxonomy indicated five categories of behaviors associated with passivity in Alzheimer's disease: diminutions of cognition, psychomotor activity, emotions, interactions with people, and interactions with the environment. Analysis indicated substantial agreement beyond chance and showed statistically significant agreement among the six nurse-expert raters. Areas of synchrony between the taxonomy and the Need-Driven Dementia Compromised Behavior Model were identified. Conclusions: This taxonomy of passive behaviors in patients with Alzheimer's disease showed empirical rigor and compatibility with a middle-range theory and can be viewed as a sensitizing analytic scheme to guide future practice, research, and theory development. [source] The electrochemical behavior of Ti-6Al-7Nb alloy with and without plasma-sprayed hydroxyapatite coating in Hank's solutionJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 5 2002I. C. Lavos-Valereto Abstract The electrochemical behavior of Ti-6Al-7Nb alloy with and without plasma-sprayed hydroxyapatite (HA) coating was investigated in Hank's balanced salt solution at 37 °C. This behavior was evaluated by analyzing both corrosion potential variation with time curves and potentiodynamic polarization curves. The polarization curves were determined both in aerated and deaerated solutions. It was found that the corrosion potential of uncoated sample is always more noble than that of coated one. In aerated solutions the polarization curve of a coating-free alloy presents a typical passive/transpassive behavior, which is absent in the HA-coated alloy and in deaerated solution for both coated and uncoated conditions. In the latter polarization curves, the current density continuously increases with the increase of the potential. The corrosion rate determined from polarization curves is higher for HA-coated alloys, but it still can be considered negligible (less than 1 ,A/cm2). © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 664,670, 2002 [source] | ||||||||||