3,626 research outputs found

    Lung Cell Toxicity of Metal-Containing Nanoparticles

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    Among the various nanomaterials present in society, many contain metals or metal compounds [...

    Quantum Test of the Universality of Free Fall

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    We simultaneously measure the gravitationally-induced phase shift in two Raman-type matter-wave interferometers operated with laser-cooled ensembles of 87^{87}Rb and 39^{39}K atoms. Our measurement yields an E\"otv\"os ratio of ηRb,K=(0.3±5.4)×107\eta_{\text{Rb,K}}=(0.3\pm 5.4)\times 10^{-7}. We briefly estimate possible bias effects and present strategies for future improvements

    Ponticulin is the major high affinity link between the plasma membrane and the cortical actin network in Dictyostelium

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    Interactions between the plasma membrane and underlying actin-based cortex have been implicated in membrane organization and stability, the control of cell shape, and various motile processes. To ascertain the function of high affinity actin-membrane associations, we have disrupted by homologous recombination the gene encoding ponticulin, the major high affinity actin-membrane link in Dictyostelium discoideum amoebae. Cells lacking detectable amounts of ponticulin message and protein also are deficient in high affinity actin-membrane binding by several criteria. First, only 10-13% as much endogenous actin cosediments through sucrose and crude plasma membranes from ponticulin-minus cells, as compared with membranes from the parental strain. Second, purified plasma membranes exhibit little or no binding or nucleation of exogenous actin in vitro. Finally, only 10-30% as much endogenous actin partitions with plasma membranes from ponticulin-minus cells after these cells are mechanically unroofed with polylysine-coated coverslips. The loss of the cell\u27s major actin-binding membrane protein appears to be surprisingly benign under laboratory conditions. Ponticulin-minus cells grow normally in axenic culture and pinocytose FITC-dextran at the same rate as do parental cells. The rate of phagocytosis of particles by ponticulin-minus cells in growth media also is unaffected. By contrast, after initiation of development, cells lacking ponticulin aggregate faster than the parental cells. Subsequent morphogenesis proceeds asynchronously, but viable spores can form. These results indicate that ponticulin is not required for cellular translocation, but apparently plays a role in cell patterning during development

    On the importance of a procedurally fair organizational climate for openness to change in law enforcement

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    OBJECTIVE: Drawing on recent work in policing and organizational psychology, we examined factors related to openness to organizational change and to adopting evidence-based interview techniques among law enforcement investigators. HYPOTHESES: We hypothesized that a procedurally fair organizational climate would predict outcomes tied to organizational change, mediated by organizational identification and perceived legitimacy. We also predicted that procedural justice factors would be stronger predictors than outcome-oriented factors (i.e., rewards and sanctions). METHOD: Study 1 surveyed law enforcement investigators (N = 711) about their attitudes toward and behaviors within their organization (i.e., perceived procedural fairness of one's organization, identification, legitimacy, compliance, empowerment, and extra-role behavior). Study 2 conceptually extended this survey to interviewers (N = 71) trained in a new, evidence-based interviewing approach adding likelihood of future use of the novel interviewing approach as an outcome. RESULTS: In Study 1, the more investigators thought their organization had a procedurally fair climate, the more they identified with the organization and perceived it as legitimate. Framing compliance, empowerment and extra-role behavior as associated with openness to change, we found that legitimacy predicted compliance and tendency toward extra-role behavior (i.e., going "above and beyond"), while level of identification predicted feelings of empowerment and extra-role behavior. Study 2 partially replicated findings from Study 1 and found that motivation to attend the training also predicted likelihood of future use. CONCLUSIONS: These studies highlight the value of a procedurally just organizational climate framework in understanding law enforcement interrogators' propensity toward implementing new evidence-based interrogation techniques. (PsycInfo Database Record (c) 2020 APA, all rights reserved)
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