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51.
This article describes the community activation and policy change process in seven Minnesota communities involved in the Tobacco Policy Options for Prevention (TPOP) study. The study's intervention employed a direct action organizing model, which relies on mobilizing large numbers of people to alter decision making and leverage the power of elites. As part of the organizing process, TPOP organizers and teams made 1,319 personal contacts with community members, generated 309 media stories, and initiated 445 public events related to tobacco use. These actions resulted in the establishment of comprehensive tobacco ordinances in all seven communities. The authors discuss the goals, training, activities and political factors relevant to four phases of the TPOP intervention: information gathering and team recruitment, community awareness building and ordinance development, preparing for city council, and ordinance establishment and enforcement. Included are suggestions for practitioners interested in using policy change and community-based advocacy to resolve public health problems.  相似文献   
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Densification behavior is investigated by means of dilatometry for powder-injection-molded (PIM) and die-compacted 17-4 PH stainless steel during sintering in pure H2 and H2 + N2. The corresponding microstructural evolution is examined by quenching in a vertical furnace at various stages of sintering. The results show that in comparison with pure H2, the H2 + N2 atmosphere retards densification and produces a lower shrinkage rate above 1220 °C. The X-ray diffraction (XRD) analysis reveals the presence of a stabilized austenitic microstructure during H2 + N2 sintering. In pure H2, however, δ ferrite forms and grows above 1220 °C, producing a higher shrinkage rate. In terms of the atomic diffusivity, δ-ferrite formation is beneficial to pore shrinkage and densification.  相似文献   
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In North America, an estimated 30,000 patients annually experience an aneurysmal subarachnoid hemorrhage (SAH). In approximately five percent of these patients, the hemorrhage is not visible on computerized tomography scans due to the inability to image blood at time intervals greater than 12 h post symptom onset. For these patients (many of which have experienced a sentinel hemorrhage that is a precursor to a more significant rupture), a method is needed for accurately analyzing cerebral spinal fluid (CSF) for evidence of SAH. Further, it is necessary to differentiate blood associated with the SAH from blood associated with the spinal tap procedure. This letter presents a point-of-care device that is capable of performing such an analysis. The stand-alone prototype device uses commercially available embedded system components to implement a point-of-care device that is capable of collecting and analyzing optical absorbance spectra. A mathematical model for the hemorrhagic CSF sample is then developed by using a partial-least-squares-regression-based regression methodology that is able to differentiate between SAH and blood associated with the spinal tap. This differentiation is achieved by quantifying bilirubin (associated with the breakdown of old blood) in the CSF. Initial testing on the prototype device suggests that the device is able to quantify bilirubin in the presence of hemoglobin over concentrations ranges that are clinically relevant to the patient population of interest.  相似文献   
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Blood-donation-related symptoms such as dizziness and weakness discourage people from participating in this important health-related activity. Four hundred sixty-seven young adult, French-speaking blood donors were randomly assigned to (a) a condition in which they learned a possible preventive technique called applied tension and were asked to practice it from the time they got on the donation chair until they were just about to get up, (b) a placebo condition in which they learned applied tension and were asked to practice it from the time they got on the chair until the insertion of the donation needle, or (c) a no-treatment control condition. Donors assigned to the treatment condition reported significantly fewer blood-donation-related symptoms than did donors assigned to the other conditions and rated their likelihood of returning to give blood again as greater than did those in the no treatment condition. Among donors whose chairs were not reclined, participants in the treatment condition had significantly smaller heart rate reactions to blood donation than did those in the other conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Upconversion nanoparticles with special fluorescence and magnetic properties have been considered an alternative contrast agent for multiple bioimaging techniques. It is important to understand the effects of the surface properties and dosage of upconversion nanoparticles on both the magnetic resonance (MRI) image and the photoluminescence spectrum. Here, NaGdF4: Er3+, Yb3+ upconversion nanoparticles (UCNPs) modified with amine functional group were produced through a one‐pot thermal decomposition. The average length of the cubic UCNPs is estimated at 53 ±13 nm. The effect of the dosage of amine modified UCNPs on the MRI image is investigated. The T1 and T2 relaxivities of the amine modified UCNPs in agarose gel at 3 T are r1 = 6.79 ±0.14 and r2 = 17.0 ±0.18 (mmol/L)?1 s?1, which are comparable to the relaxivities of commercially available MRI contrast agents. In addition, the photoluminescence of the amine modified UCNPs at low concentrations < 150 µg/mL are further investigated with the excitation wavelength (λex) at 980 nm. The internalization of the amine modified UCNPs cultured with human umbilical vascular endothelial cells (HUVEC) is observed by the fluorescence imaging. Meanwhile, T1‐weighted MRI imaging of HUVEC cells treated with amine modified UCNPs at 10 µg/mL can be obtained. No significant toxic effect on cells is found when the concentration of the amine modified UCNPs is < 300 µg/mL. This study indicates that a low concentration of amine‐modified NaGdF4: Er3+, Yb3+ UCNPs can be used as the contrast agent for both fluorescence imaging and magnetic resonance imaging.  相似文献   
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Perseverative behavior has not been extensively studied in patients with dementia. In this study, perseverative behavior was elicited with the dementia version of the Graphical Sequence Test. A control group and participants with Alzheimer's disease (AD) and subcortical ischemic vascular dementia (IVD) were studied. A factor analysis revealed a 3-factor model consisting of perseverations related to semantic knowledge, motor functioning, and a third, intermediary factor. IVD participants made more total perseverations than did AD participants. Perseverations made by AD participants were correlated with deficits on tests of semantic knowledge, whereas the perseverations made by IVD participants were correlated with motor and frontal systems tests. Results are consistent with the view that perseverative behavior is hierarchically arranged in terms of specific levels of cognitive complexity and the overall pattern of cognitive deficits associated with each type of dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The central theme of this article relates to the legislative steps taken by the Government of the United States and its promulgation and enforcement of environmental quality standards in response to the nationwide concern with respect to the detrimental impact of automotive transportation upon the environment. Three aspects of this degrading impact are covered: pollution of the atmosphere by emissions from motor vehicles; scarring of the natural beauty of the landscape contiguous to highways, and the emission of physiologically harmful noise by automotive vehicles moving upon highways and streets, especially heavy duty trucks and tractor‐trailer units. The concluding sections direct attention to the need for cooperative action on the part of the Federal, State and local governments, automotive and oil industries and an aroused populace in the formulation and the rigid enforcement of corrective environmental policies and practices, pertaining to automotive transportation.  相似文献   
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