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The outbreak of the toxic capsule crisis during April 2012 aroused widespread public concern about the risk of chromium-contaminated capsules and drug safety in China. In this article, we develop a conceptual model to investigate risk perceptions of the pharmaceutical drug capsules and behavioral responses to the toxic capsule crisis and the relationship between associated factors and these two variables. An online survey was conducted to test the model, including questions on the measures of perceived efficacy of the countermeasures, trust in the State FDA (Food and Drug Administration), trust in the pharmaceutical companies, trust in the pharmaceutical capsule producers, risk perception, concern, need for information, information seeking, and risk avoidance. In general, participants reported higher levels of risk perception, concern, and risk avoidance, and lower levels of trust in the three different stakeholders. The results from the structural equation modeling procedure suggest that perceived efficacy of the countermeasures is a predictor of each of the three trust variables; however, only trust in the State FDA has a dampening impact on risk perception. Both risk perception and information seeking are significant determinants of risk avoidance. Risk perception is also positively related to concern. Information seeking is positively related to both concern and need for information. The theoretical and policy implications are also discussed.
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Cápsulas , Cromo/toxicidade , Contaminação de Medicamentos , Modelos Teóricos , Medição de Risco , Adulto , China , Pesquisa Empírica , Humanos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
In the title Schiff base mol-ecule, C13H9ClFNO, the benzene rings are twisted slightly with respect to each other, making a dihedral angle of 7.92â (2)°. An intra-molecular O-Hâ¯N hydrogen bond occurs. In the crystal, an infinite chain is formed along the c-axis direction by π-π stacking inter-actions between the phenyl rings and the six-membered hydrogen-bonded ring of neighboring Schiff base ligands [centroid-centroid distances of 3.698â (2) and 3.660â (3)â Å]. Neighboring chains are linked into a three-dimensional supra-molecular structure by C-Hâ¯O and C-Hâ¯F hydrogen bonds.
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Since the concept of toughness was introduced to transportation systems, transportation system toughness has received extensive attention from researchers in the field of transportation worldwide. In this paper, a methodology for quantifying and assessing the toughness of urban transportation systems is proposed in the context of the New Crown epidemic. Firstly, the definition of urban transportation system toughness in this context is clarified, and the entropy evaluation method is applied to construct the performance curve of urban transportation systems over time. Then, it is proposed to quantify the system's resistance, recovery, and adaptive ability in terms of the change in the cumulative amount of system performance. Finally, the three characteristic abilities of system toughness are organically combined to obtain a comprehensive assessment of system toughness. Example calculations and analyses are carried out in four Chinese cities with different levels of development, and the results show that the performance of urban transportation systems is positively correlated with their levels of development, and all of them fluctuate greatly under the influence of the epidemic, but Wuhan has the strongest resistance and recovery ability of the transportation system, and shows the highest toughness, followed by Lanzhou, Changchun, and Shanghai. The system toughness quantification and assessment methods proposed in this paper provide a reference for research on improving the ability of urban transportation systems to deal with multiple uncertainty disturbances.
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Epidemias , Meios de Transporte , China , Cidades , Entropia , IncertezaRESUMO
In order to further study the expansion characteristics of left-turning non-motorized vehicles at intersections and the relationship between expansion characteristics and vehicle-bicycle conflicts, the trajectory point data of left-turning non-motorized vehicles are extracted using video trajectory tracking technology, and construct the cubic curve expansion envelope equation with the highest fitting degree. For the purpose of quantifying the expansion degree of non-motor vehicles after starting, two intersections in Guangxi Zhuang Autonomous Region were selected for case analysis, and the numerical range of expansion degree of the intersection with a left-turn waiting area and the intersection without a left-turn waiting area was obtained. Study the mathematical relationship between the expansion degree and its influencing factors, and establish the multivariate nonlinear regression equation between the expansion degree and the left-turn non-motorized vehicle flow, the number of parallel non-motorized vehicles, and the left-turn green light time. Analyze the vehicle-bicycle conflicts caused by the expansion of left-turning non-motorized vehicles, determine the essential factors affecting the number of non-motorized vehicles, and establish the multiple linear regression equation between the number of non-motorized vehicles and the number of left-turning non-motorized vehicles, the expansion degree, and the number of parallel non-motorized vehicles, the results show that the model has high accuracy. By analyzing the expansion characteristics of left-turning non-motorized vehicles at intersections, the relationship between different influencing factors and the expansion degree is obtained. Then the vehicle-bicycle conflicts under the influence of expansion characteristics is analyzed, providing theoretical ideas for improving traffic efficiency and optimizing traffic organization at intersections.
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Acidentes de Trânsito , Ciclismo , ChinaRESUMO
In the title compound, [PdCl(2)(C(6)H(6)N(2)O(2))(2)], the Pd(II) atom is coordinated in a distorted square-planar geometry by two N atoms from two 4-nitro-aniline ligands and two Cl atoms in a trans arrangement. Inter-molecular N-Hâ¯Cl hydrogen bonds involving the amino groups and chloride anions lead to a chain along [100]. These chains are further self-assembled into a three-dimensional network through N-Hâ¯O and N-Hâ¯Cl hydrogen bonds.
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In the title dinuclear complex, [Pb(2)(C(7)H(4)ClO(2))(4)(C(10)H(8)N(2))], the Pb(II) atom is five-coordinated by four carboxyl-ate O atoms from two 2-chloro-benzoate ligands and one N atom from a bridging 4,4'-bipyridine (4,4'-bpy) ligand, displaying a hemi-directed coordination. The 4,4'-bpy ligand has an inversion center at the mid-point of the central C-C bond. The empty side of the metal ion is capped by two carboxyl-ate O atoms from a neighboring mol-ecule, with weak Pbâ¯O contacts [Pbâ¯O = 3.069â (2) and 3.071â (3)â Å]. The crystal structure is stabilized by C-Hâ¯O hydrogen bonds and π-π stacking inter-actions between the benzene and pyridine rings [centroid-centroid distance = 3.749â (3)â Å].
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In the context of the recent recalls of contaminated pet food and lead-painted toys in the United States, we examine patterns of risk perceptions and decisions when facing consumer product-caused quality risks. Two approaches were used to explore risk perceptions of the product recalls. In the first approach, we elicited judged probabilities and found that people appear to have greatly overestimated the actual risks for both product scenarios. In the second approach, we applied the psychometric paradigm to examine risk perception dimensions concerning these two specific products through factor analysis. There was a similar risk perception pattern for both products: they are seen as unknown risks and are relatively not dread risks. This pattern was also similar to what prior research found for lead paint. Further, we studied people's potential actions to deal with the recalls of these two products. Several factors were found to be significant predictors of respondents' cautious actions for both product scenarios. Policy considerations regarding product quality risks are discussed. For example, risk communicators could reframe information messages to prompt people to consider total risks packed together from different causes, even when the risk message has been initiated due to a specific recall event.
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Ração Animal/efeitos adversos , Tomada de Decisões , Contaminação de Alimentos , Chumbo/análise , Jogos e Brinquedos/lesões , Medição de Risco , Animais , Doenças do Cão/induzido quimicamente , Doenças do Cão/mortalidade , Cães , Exposição Ambiental , Indicadores Básicos de Saúde , Humanos , Masculino , Psicometria , Análise de RegressãoRESUMO
In the title coordination polymer, {[AgNd(C(5)H(3)N(2)O(2))(2)(C(2)O(4))]·H(2)O}(n), the Nd(III) atom is coordinated in a distorted monocapped square-anti-prismatic geometry by two O and two N atoms of two N,O-bidentate pyrazine-2-carboxyl-ate (2-pzc) ligands, four O atoms of two bidentate oxalate ligands, and one O atom of a monodentate carboxyl-ate group of a 2-pzc ligand. The Ag(I) ion is coordinated in a distorted tetra-hedral geometry by two N atoms from two monodentate 2-pzc ligands, one O atom from one monodentate oxalate ligand and one O atom of a bridging carboxyl-ate group of a 2-pzc ligand. The oxalate anions link neighbouring neodymium(III) metal centres into Nd-oxalate chains, which are inter-connected by Ag(2-pyz)(2) units, forming a three-dimensional polymeric framework. Inter-molecular O-Hâ¯O and C-Hâ¯O hydrogen bonds are observed in the crystal structure.
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In the title coordination polymer, {[Ag(4)Er(2)(C(6)H(4)NO(2))(5)(C(2)O(4))(2)(NO(3))(H(2)O)]·4H(2)O}(n), each Er(III) atom is coordinated in a bicapped trigonal-prismatic coordination geometry by three O atoms from two isonicotinate (IN) ligands, four O atoms from two oxalate ligands and one O atom from either a nitrate ion or a water mol-ecule, both of which are half-occupied over the same site. One Ag(I) atom has a Y-shaped geometry defined by one N atom from one IN ligand, one O atom from another IN ligand and one O atom from an oxalate ligand. The other Ag(I) atom is coordinated by two IN ligands and one O atom from an oxalate ligand. One of the IN ligands is disordered over an inversion center and forms a bridge between two centrosymmetric Ag(I) ions. Due to the disorder, this IN ligand coordinates to the Ag atom through either the pyridyl N or the carboxyl-ate O atoms. The IN and oxalate ligands link the Er and Ag atoms into a three-dimensional coordination framework. O-Hâ¯O and C-Hâ¯O hydrogen bonds are observed in the crystal structure.