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1.

High rates of intercontinental exchange of plant species have caused scientists to ask whether floristic areas with similar environments are undergoing global homogenization. We focused on riparian forests of the urban Salt River (Sonoran Desert, USA) to ask: (1) Is the forest dominated by cosmopolitan or provincial elements? (2) Which trees planted in the irrigated cityscape have established along the river? (3) Which types of restoration interventions have favored provincial species? We surveyed tree abundance, size and vigor in belt transects among five reaches that differed in degree of restoration, and obtained data on tree species composition of the urban landscape and pre-development riparian zone. Our results reveal the urban riparian forest to have many cosmopolitan elements, owing in part to spillover of trees from the cultivated cityscape (e.g., Acacia stenophylla, Vitex agnus-castus). Global spread of some regional (Neotropical) riparian taxa (e.g., Parkinsonia aculeata, Prosopis) also has contributed to the cosmopolitan status. Yet, the forests retain a distinct regional signature. Unintentional restoration of winter floods has allowed for regeneration of Salix gooddingii, a vernally-adapted provincial pioneer, although its long-term survivorship is restricted to limited micro-sites (storm drain outfalls). Urbanization-related changes in stream hydrogeomorphology explain increases in some regional species (e.g., Washingtonia spp.) that historically were excluded from the river.

Reaches restored by planting, weeding, watering, and geocountouring had the greatest abundance of provincial species and greatest floristic similarity to historic conditions.

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2.
If the government's goal is to raise tax revenue in a cost-effective manner, which (if any) occupation categories could be targeted with a higher probability of an audit to yield increased revenue? Looking beyond mere opportunity to evade (e.g., self-employment) and starting from the premise that taxpayers in certain occupations evade more than others, the issue is whether these taxpayers respond to a change in the audit rate. Theory suggests that compliance increases in response to higher audit rates; the occupations with the higher evaders could therefore be targeted. This theory is tested by drawing a connection between occupation, reputation, and tax compliance. We assume that taxpayers in occupations with high need for reputation respond to a lower extent to increased tax audits than taxpayers whose achievement does not depend on reputation. The results support the effectiveness of raising tax revenue by targeting specific occupations, non-managers, with a higher probability of an audit.  相似文献   

3.
An alternative approach to organizational theory is outlined, based on Marxian categories and propositions. The concepts of “productive force” and “social relations of production” are specified in terms of various organizational phenomena such as organizing activity vs. organization; historical contradictions between organizational control structures and new forms of organizing work activity (e.g., occupational and professional status groups vs. administrative rationalization and bureaucratization; bureaucratic and technocratic administration vs. self-organization of labor and workers' control); the contradictions between such organizational dimensions as labor-power and its manifestations in terms of skills and knowledge, the object of labor (complexity of task structure), the means of labor (technology), the division of labor, the control of labor (cost-accounting and hierarchical authority relations), and the organization of labor (e.g., either in terms of occupations and professions or unions, corporate management, state bureaucracies, or self-organization and workers' control). Organizational contradictions between functional as well as historical phases of the work process are described for work organizations, in general, and for public service bureaucracies and courts of law, in particular. For example, administrative and technical innovations designed to increase productivity tend to come into contradiction with strategies of established authority structures (e.g., of the professional judicial elite) designed to expand domain, thus impeding or nullifying various organizational reform efforts. The paper concludes with a more general discussion of Marxian method.  相似文献   

4.
This research utilized a novel methodology to explore the relative salience of facial cues to age, sex, race, and emotion in differentiating faces. Inspired by the Stroop interference effect, participants viewed pairs of schematic faces on a computer that differed simultaneously along two facial dimensions (e.g., race and age) and were prompted to make similarity judgments about the faces along one of the dimensions (e.g., race). On a second round of trials, judgments were made along the other dimension (e.g., age). Analysis of response speed and accuracy revealed that participants judged the race of the faces more quickly and with fewer errors compared to their age, gender, or emotional expression. Methodological and theoretical implications for studying the role of facial cues in social perception are discussed.  相似文献   

5.
Intermarriage and homogamy: causes,patterns, trends   总被引:1,自引:0,他引:1  
"Although many characteristics play a role in the choice of a spouse, sociologists have most often examined endogamy and homogamy with respect to race/ethnicity, religion, and socioeconomic status.... I summarize empirical research by answering four questions: (a) To what extent are groups endogamous and how do groups differ in this respect? (b) How has endogamy changed over time? (c) Which factors are related to endogamy? (d) How do various dimensions of partner choice coincide? [I then] discuss strengths and weaknesses of past research."  相似文献   

6.
The current study assesses: (1) whether the relationship between individual exposure to coworker substance use and negative consequences resulting from exposure depends on work group membership, and (2) whether group-level characteristics moderate the relationship between exposure and consequences. At the group-level, we assessed occupations involving safety risk or high mobility and social factors of drinking climate and group cohesiveness. We conducted Hierarchical Linear Modeling (HLM) across two samples of municipal employees (ns = 650, 878; n of groups = 50, 49). Our results revealed that groups with higher proportions of jobs involving risk (e.g., machine work) and, to a lesser extent, groups with a higher level of drinking climate were those most vulnerable to consequences under conditions of exposure. Importantly, our findings controlled for individual risk factors (e.g., personal drinking, job stress). Our discussion examines the implications of this study for theory and policy related to workplace substance abuse.  相似文献   

7.
Data from a 1992 survey (N = 2,377) of the population of Taiwan show that class identification is rooted in the objective stratification system: the higher one's education, occupational status, power, and income, the more likely one is to identify with the middle or upper classes rather than the working or lower classes. Class interest theory predicts that the higher a person's objective position and subjective class identification, the more likely s/he is to hold a conservative ideology concerning class issues (e.g., do large firms have too much power? Should employees protest against their employer's personnel practices, and go on strike?). Multiple regression analysis provides only partial confirmation for class interest theory. The finding that the most educated and those in professional and technical occupations are the least conservative on class issues is interpreted as supporting a “new class” form of class interest theory. While the Taiwan respondents are not generally conservative on these class issues, their class identification appears to have little to do with whether they are conservative or nonconservative, either before or after objective position in the stratification system is held constant.  相似文献   

8.
Occupation segregation is a persistent aspect of the labour market, and scholars have often researched what happens when women and men enter into what are seen to be ‘non‐traditional’ work roles for their sex. Research on men within women's roles has concentrated mainly on the challenges to a masculine identity, while research on workplace language has focused on women's linguistic behaviour in masculine occupations. To date, there has been relatively little research into the linguistic behaviour of men working in occupations seen as women's work (e.g., nursing, primary school teaching). To address this gap, this article focuses on men's discursive behaviour and identity construction within the feminized occupation of nursing. Empirical data collected by three male nurses in a hospital in Northern Ireland is explored using discourse analysis and the Community of Practice paradigm. This paper discusses how the participants linguistically present themselves as nurses by performing relational work and creating an in‐group with their nurse colleagues by actively using an inherently ‘feminine’ discourse style.  相似文献   

9.
The paper reviews different approaches to, and current knowledge of the measurement of occupational segregation, using the case of gender segregation. It shows that most popular segregation ‘indices’ are actually statistics of association in a 2x2 table, often with distorting weightings. The dimensions of segregation comprise a vertical dimension measuring inequality and an orthogonal horizontal one measuring difference without inequality. Together, the dimensions make up segregation as generally understood; so segregation and its dimensions require consistent measurements. Conditions for suitable measures are considered, and the limitations of the various measures noted. The alternative conception of segregation, where all occupations are treated as though they were the same size, is shown to be seriously flawed. The most useful measures are selected and shown to be related as Lorenz curves. Since all segregation measures vary with the number of occupations considered, standardisation on 200 occupations is introduced for the chosen measures.  相似文献   

10.
This study examines the relative importance of soft skills versus hard skills across occupations and its impact on the observed wage gap between Blacks and Whites in the United States. It posits that the Black/White pay gap may vary across occupations that require the use of different types of skills. We classify occupations into hard‐skill intensive versus soft‐skill intensive jobs using the skill content measures of different occupations from the Occupational Information Network (O*Net). We then use data from the National Longitudinal Survey of Youth (NLSY) and Current Population Survey (CPS) to investigate the impact of job skill type on the wage gap. Consistent with our theoretical predictions, we show that this wage gap in white‐collar jobs is smaller for hard‐skills jobs than it is for soft‐skills jobs. Moreover, we demonstrate that, in response to variations in the wage gap across different occupations, Blacks are more likely to self‐select themselves into hard‐skills jobs, ceteris paribus. This shows not only that discrimination against Blacks varies across occupations, but also that such discrimination induces the self‐selection of Blacks into certain occupations. Moreover, this finding highlights the role played by co‐worker/customer discrimination in explaining the racial wage gap in the U.S. labor market. (JEL J15, J31)  相似文献   

11.
We examine the sources of traditional gender attitudes during a period of social conflict and change. Using survey data from Croatia (Center for the Investigation of Transition and Civil Society, 1996; N= 2,030) we explore the relationships between war‐related experiences, in‐group and out‐group polarization, and two dimensions of gender attitudes: policy attitudes (e.g., attitudes toward divorce and abortion) and gendered family roles (e.g., attitudes toward the division of household labor). We argue that ethnic conflict promotes in‐group polarization (i.e., attachment to the Croatian nation) and out‐group polarization (i.e., distrust of “others”), which lead to a resurgence of traditional values, including traditional gender attitudes. We also examine the effects of childhood socialization, individual resources, and interpersonal familial ties on gender attitudes. Results support the conflict‐group polarization model and indicate that out‐group polarization has the most powerful effect on both gendered family role attitudes and policy attitudes for men and women. In‐group polarization does not affect gender attitudes, however.  相似文献   

12.
Tipping is an important economic phenomenon, involving about $47 billion a year in the US food industry alone, and trillions of dollars across different occupations and countries over the years. Moreover, tipping is a major source of income for millions of workers. This article discusses the implications of tipping for business strategy in the relevant industries. For example, firms can choose to impose a compulsory service charge in lieu of tipping - what are the advantages and disadvantages of doing so? How does tipping change the profit-maximizing level of investing in screening job applicants, training workers, monitoring them, and providing performance-based incentives by the firm? Can industries such as the music industry use tips (i.e., prices being voluntary and determined by the customers) as an alternative business model?  相似文献   

13.
14.
Guided by a life course perspective, this study examined the effects of transitioning into caregiving activity for a child, spouse, parent, other relative, or nonkin associate on nine dimensions of psychological well‐being. Data came from adults ages 19–95, who were noncaregiver primary respondents in the National Survey of Families and Households in 1987–88 and who were followed up longitudinally in 1992–93 (N= 8,286). Results from multivariate regression models confirmed that the transition to caregiving for primary kin (i.e., a child, spouse, or biological parent) was associated with an increase in depressive symptoms. However in selected instances, caregiving was associated with beneficial effects (e.g., women who began to provide nonresidential care to a biological parent reported more purpose in life than noncaregiving women). Evidence regarding gender differences was inconsistent, varying across caregiving role relationship types.  相似文献   

15.
Using two waves of panel data from the National Survey of Midlife in the United States (MIDUS), we examine the relationship between volunteer work and three dimensions of well‐being: hedonic (e.g., positive mood), eudemonic (e.g., purpose in life), and social (e.g., feeling of belonging to the community). We test for the effects of volunteering measured as a binary and a continuous variable. Results show that volunteering enhances eudemonic and social well‐being (but not hedonic well‐being) although the number of hours contributed makes no difference. Conversely, people who have greater hedonic, eudemonic, and social well‐being are more likely to volunteer and, in the case of hedonic and eudemonic well‐being, volunteer more hours.  相似文献   

16.
Infants encode the surface features of simple, unfamiliar objects (e.g., red triangle) and the categorical identities of familiar, categorizable objects (e.g., car) into their representations of these objects. We asked whether 16–18-month-olds ignore non-diagnostic surface features (e.g., color) in favor of encoding an object's categorical identity (e.g., car) when objects are from familiar categories. In Experiment 1 (n = 18), we hid a categorizable object inside an opaque box. In No Switch trials, infants retrieved the object that was hidden. In Switch trials, infants retrieved a different object: an object from a different category (Between-Category-Switch trials) or a different object from the same category (Within-Category-Switch trials). We measured infants' subsequent searching in the box. Infants' pattern of searching suggested that only infants who completed a Within-Category-Switch trial as their first Switch trial encoded objects' surface features, and an exploratory analysis suggested that infants who completed a Between-Category-Switch trial as their first Switch trial only encoded objects' categories. In Experiment 2 (n = 18), we confirmed that these results were due to objects' categorizability. These results suggest infants may tailor the way they encode categorizable objects depending on which object dimensions are perceived to be task relevant.  相似文献   

17.
Recent work has shown that young children can use fine phonetic detail during the recognition of isolated and sentence‐final words from early in lexical development. The present study investigates 24‐month‐olds' word recognition in sentence‐medial position in two experiments using an Intermodal Preferential Looking paradigm. In Experiment 1, French toddlers detect word‐final voicing mispronunciations (e.g., bu z [by z ] for bu s [by s ] “bus”), and they compensate for native voicing assimilations (e.g., bu z d evant toi [bu zd ?vɑ?twa] “bus in front of you”) in the middle of sentences. Similarly, English toddlers detect word‐final voicing mispronunciations (e.g., shee b for shee p ) in Experiment 2, but they do not compensate for illicit voicing assimilations (e.g., shee b th ere). Thus, French and English 24‐month‐olds can take into account fine phonetic detail even if words are presented in the middle of sentences, and French toddlers show language‐specific compensation abilities for pronunciation variation caused by native voicing assimilation.  相似文献   

18.
Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential landscapes will be similar regardless of whether residents live in the humid East or the arid West, or the warm South or the cold North. Results underscored that cultural services were of utmost importance, particularly anthropocentric values including aesthetics, low-maintenance, and personal enjoyment. Using factor analyses, distinctive dimensions of residents’ values were found to partially align with the Millennium Ecosystem Assessment’s categories (provisioning, regulating, supporting, and cultural). Finally, residents’ ecosystem service priorities exhibited significant homogenization across regions. In particular, the traditional lawn aesthetic (neat, green, weed-free yards) was similarly important across residents of diverse U.S. cities. Only a few exceptions were found across different environmental and social contexts; for example, cooling effects were more important in the warm South, where residents also valued aesthetics more than those in the North, where low-maintenance yards were a greater priority.  相似文献   

19.
20.
This is a systematic review of 30 years (1988‐2017) of empirical research on processes of religious/spiritual influence in adolescence. We followed a multi‐step process that resulted in 241 studies organized according to eight research questions and the corresponding methods and analyses typically used to address them. We coded these studies based on the dimensions of religiosity/spirituality and the youth outcomes involved. In some cases (quantitative studies of mediation and moderation, as well as qualitative studies) we also coded a third process variable. Results of the coding process revealed a number of interesting patterns. First, religiosity/spirituality is generally adaptive for adolescents, protecting them from negative outcomes (e.g., risk behaviors and mental illness), and promoting positive youth development and flourishing. Nevertheless, in some contexts, religiosity/spirituality may be at least partially maladaptive. Second, there is some evidence, from experimental and longitudinal studies, that relations between religiosity/spirituality and adaptive outcomes are causal. Third, there are numerous complex and dynamic processes by which religiosity/spirituality relate to youth outcomes. In terms of mediation studies, the most salient mediating processes seem to involve religiosity/spirituality dimensions, peers, values/attitudes, and social control/norms. Fourth, religiosity/spirituality is multidimensional, involving various interwoven facets at the individual and ecological levels. Private or personal aspects of religiosity/spirituality (e.g., religious/spiritual importance) tend to be more salient predictors of outcomes than public aspects of religiosity/spirituality (e.g., religious worship service attendance). The results of this systematic review point to promising directions for future research. First, more research is needed studying a broader range of dimensions of religiosity/spirituality, processes of influence, and outcomes. In terms of religiosity/spirituality, much of the prior work has focused on overall religiosity/spirituality, and religious/spiritual behaviors (e.g., worship service attendance). In terms of outcomes, the emphasis has been on religiosity/spirituality protecting against maladaptive outcomes (e.g., substance use). Second, more research is needed examining the role of culture, and using more rigorous methods (e.g., experience sampling, experimental design, longitudinal design, or mixed methods). This systematic review provides a detailed analysis of what is known regarding processes of religious/spiritual influence in the lives of adolescents, and hopefully better positions researchers to move the field forward.  相似文献   

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