Predicting River Travel Time from Hydraulic Characteristics

Predicting the effect of a pollutant spill on downstream water quality is primarily dependent on the water velocity, longitudinal mixing, and chemical∕physical reactions. Of these, velocity is the most important and difficult to predict. This paper provides guidance on extrapolating travel-time information from one within bank discharge to another. In many cases, a time series of discharge (such as provided by a U.S. Geological Survey stream gauge) will provide an excellent basis for this extrapolation. Otherwise, the accuracy of a travel-time extrapolation based on a resistance equation can be greatly improved by assuming the total flow area is composed of two parts, an active and an inactive area. For 60 reaches of 12 rivers with slopes greater than about 0.0002, travel times could be predicted to within about 10% by computing the active flow area using the Manning equation with n = 0.035 and assuming a constant inactive area for each reach. The predicted travel times were not very sensitive to the assumed values of bed slope or channel width.     

The Great Lakes Cladophora Model: Development,testing, and application to Lake Michigan

A recent review of the Great Lakes Water Quality Agreement has concluded that while controls on phosphorus inputs to Lake Michigan achieved the desired effect in offshore waters, the nearshore region continues to suffer from elevated phosphorus levels. Failure to achieve trophic state goals in the nearshore is manifested in nuisance growth of Cladophora and attendant impacts on property owners, utilities, and the public health and welfare. This study focuses on a site in Lake Michigan near Milwaukee, Wisconsin, where nuisance growth of Cladophora and associated beach fouling occur regularly. A mechanistic model simulating Cladophora growth, suitable for guiding nutrient management in the Great Lakes nearshore, is presented. The model represents an update of the Canale and Auer framework, reflecting current understandings of Cladophora ecology and offering a user-friendly interface making the software more widely available to decision makers. This Great Lakes Cladophora Model (GLCM) is first validated for the Auer/Canale data set collected in 1979 at a site on Lake Huron and then for a data set developed in 2006 for a site on Lake Michigan. Model performance under the strikingly different forcing conditions (depth, light, phosphorus levels) characteristic of these two sites affirms the widespread applicability of the tool. The GLCM is then extended to examine the impacts of ecosystem perturbation (dreissenid colonization) on Cladophora growth and to future approaches to monitoring and management.     

Predicting clinically significant response to cognitive behavior therapy for chronic insomnia in general medical practice: Analyses of outcome data at 12 months posttreatment.

The clinical efficacy of cognitive behavior therapy (CBT) for chronic insomnia has been established, yet clinical effectiveness is less clear. This study presents data on 109 patients from general practice during a formal evaluation of clinical effectiveness. Two thirds achieved normative values of ≤30 min for sleep latency and wakefulness during the night after CBT. Furthermore, almost half of the sample reduced sleeplessness by ≥50%. Logistic regression revealed that initial severity did not contraindicate good outcome. Rather, greater sleep disturbance was positively associated with large symptom reduction, although lower endpoint scores were less likely. Similarly, symptoms of anxiety, depression, and thinking errors positively predicted good outcome. Hypnotic using patients responded equally well to CBT, and demographic factors were of no significant predictive value. It is concluded that CBT is clinically and durably effective for persistent insomnia in routine practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Challenge of computers in psychological assessment.

The authors discuss the advantages and limitations of computers in psychological assessment in terms of (a) the need to validate computer-based test interpretation systems; (b) the impact of computerization on psychometric properties of instruments; (c) the potential innovative uses of computers; (d) acceptance of computers by staff and clients; and (e) professional concerns regarding standards, accountability, and reimbursement. It is concluded that it is time for psychology to develop standards and policies for the professional and responsible use of computers in psychological assessments. (75 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Investigating teacher stress when using technology

In this study we use a model which we refer to as the ‘teacher–technology environment interaction model’ to explore the issue of the stress experienced by teachers whilst using ICT in the classroom. The methodology we used involved a comparison of three datasets obtained from: direct observation and video-logging of the teachers in the classroom; recordings of their galvanic skin response (GSR) taken whilst teaching; and interviews. Data were obtained from nine teachers, and in total, approximately 32 h of teaching activities were observed. The main results of this study were (a) the demonstration that teachers do suffer stress associated with the use of technology in the classroom (i.e. technostress) (b) the identification of causes, symptoms and coping strategies associated with technostress in the classroom. This study, therefore, points to an alternative way of thinking about the problems of implementing e-learning by conceptualizing some of these implementation problems in terms of technostress (and in particular of teacher–technology environment fit).     

Use of a Web site for learning about cancer

This paper is an assessment of the use of CancerHelp UK, a Web site developed as a resource for people living with cancer. Attitudes to the use of the site were examined through interviews with 23 patients and relatives in a two-phase pilot study. The analysis of the data was conducted within a framework derived from activity theory which focused on individual perspectives, purposes and outcomes and the processes involved in use. Our findings show that the process of using the site and the characteristics of the medium were regarded as beneficial, although some inexperienced computer users needed some help. There were positive cognitive and affective outcomes for those who had independently chosen to use the site. However, there were differences in process and outcome between independent users and participants who had been invited to use the resource for evaluation purposes. The study raises questions about the use and evaluation of the World Wide Web for teaching and learning through an informal learning activity. The response of participants to the use of CancerHelp UK indicates that the resource is both useful and usable. The authors suggest that the availability of the Web as a means for learning about cancer may challenge the traditional transmission-based practice of the medical consultation.     

Similar–other support for men undergoing coronary artery bypass surgery.

This field experiment examined effects of a support intervention on the physical and mental health of coronary artery bypass graft (CABG) surgery patients. Control participants (N?=?90) received usual hospital care; experimental participants (N?=?100) also received visits from a "similar other" while in the hospital. Similar others were Veterans Administration veterans who had CABG surgery previously and were trained in simple supportive techniques. Outcomes were assessed prior to surgery and at 1, 6, and 12 months afterwards. Unexpectedly, the intervention generally had no effects on participants' well-being. Further analysis showed that participants who talked often with fellow cardiac patients in the hospital ("de facto similar others") experienced improvements in their physical and emotional well-being over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acute effects of ingesting Java Fit™ energy extreme functional coffee on resting energy expenditure and hemodynamic responses in male and female coffee drinkers

Background  

The purpose of this study was to examine the effects of a functional coffee beverage containing additional caffeine, green tea extracts, niacin and garcinia cambogia to regular coffee to determine the effects on resting energy expenditure (REE) and hemodynamic variables.     

Group size and social interactions are associated with calling behavior in Carolina chickadees (Poecile carolinensis).

The complexity of a social group may influence the vocal behavior of group members. Recent evidence in Carolina chickadees, Poecile carolinensis, indicated that one component of social complexity, group size, influenced the complexity of the "chick-a-dee" call, a vocalization functioning in social cohesion. Individuals in larger social groups used calls with greater information than did individuals in smaller social groups. Here, the authors review this earlier work, and describe a recent study indicating that social interactions between females and males within female-male pairs of chickadees were associated with rates of chick-a-dee call production in the males. Together, these studies suggest that the nature and complexity of social interactions among members of chickadee social groups influence chick-a-dee calling behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)