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901.
Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the
relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations
between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific
indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing
percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment
urbanization levels greater than 10%. There was a strong collinear relationship (r
2 = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity
(μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile
regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate
(NO3-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic
macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated
with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing
water quality in major tributaries and the Chesapeake Bay. 相似文献
902.
Ovarian cancer is the leading cause of gynaecological cancer death. The mortality rate of ovarian cancer could be greatly decreased if there were a screening test which was able to detect the disease at an early stage, resulting in an increased probability of cure. The most promising prospect for the early detection of ovarian cancer comes from the rapidly advancing field of clinical proteomics. An increasing number of reports on the potential clinical application of proteomics research for early detection as well as risk assessment and management of ovarian cancer are being published. Although the research is very promising, major technical challenges are still preventing new discoveries in ovarian cancer proteomics from being translated into clinical practice. 相似文献
903.
904.
The myth of problem-free living is easily identifiable in Western culture through its childhood fairy tales and modern love stories. Even if inadvertently, the field of mental health perpetuates this myth with the very concept of "mental health," which implies a state without suffering. Using mindfulness, Buddhists assume an alternative stance towards suffering: rather than eliminate it, they compassionately engage it. This article explores the potentials of mindfulness as an alternative approach to suffering within the context of marriage and family therapy. Family therapists can integrate mindfulness principles into their work to help clients shift how they relate to the unique forms of suffering that one encounters in intimate relationships, such as abuse, divorce, rejection, and loss. 相似文献
905.
The life course perspective on drug use: a conceptual framework for understanding drug use trajectories 总被引:1,自引:0,他引:1
This article discusses the life course perspective on drug use, including conceptual and analytic issues involved in developing the life course framework to explain how drug use trajectories develop during an individual's lifetime and how this knowledge can guide new research and approaches to management of drug dependence. Central concepts include trajectories marked by transitions and social capital and turning points influencing changes. The life course perspective offers an organizing framework for classifying varying drug use trajectories, identifying critical events and factors contributing to the persistence or change in drug use, analytically ordering events that occur during the life span, and determining contributory relationships. 相似文献
906.
Psychiatric nurses should support best practices to prevent youth violence. The magnitude and significance of youth violence gives us both social and moral mandates to proceed. Health care professionals have made giant strides in sparing our children from the ravages of childhood diseases. Let us try to do the same by preventing the development of violent behaviors. 相似文献
907.
908.
Louis A. Penner Heather Orom Terrance L. Albrecht Melissa M. Franks Tanina S. Foster John C. Ruckdeschel 《Journal of Nonverbal Behavior》2007,31(2):99-117
Video recording provides an objective record of the content of medical interactions. However, there is concern that cameras
may be reactive measurement devices that alter what normally transpires during interactions. This study addressed potential
reactivity of cameras in medical interactions. Interactions between 45 patients and 14 medical oncologists were video recorded
and coded for camera-related behaviors. Eleven of 45 patients performed none of the behaviors. Among the other patients, camera-related
behaviors were infrequent and, on average, constituted about 0.1% (one-tenth of one percent) of total interaction time. Behaviors
occurred most often in very early stages of interactions, and when physicians were absent from the room. Seven physicians
showed camera-related behaviors, comprising less than 0.1% of the time they were in the interaction. Results suggest video
recording can provide nonreactive means of studying medical interactions.
相似文献
Louis A. PennerEmail: |
909.
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