Model application niche analysis: Assessing the transferability and generalizability of ecological models.

The use of models by ecologists and environmental managers, to inform environmental management and decision-making, has grown exponentially in the past 50 years. Due to logistical, economical, and theoretical benefits, model users frequently transfer preexisting models to new sites where data are scarce. Modelers have made significant progress in understanding how to improve model generalizability during model development. However, models are always imperfect representations of systems and are constrained by the contextual frameworks used during their development. Thus, model users need better ways to evaluate the possibility of unintentional misapplication when transferring models to new sites. We propose a method of describing a model's application niche for use during the model selection process. Using this method, model users synthesize information from databases, past studies, and/or past model transfers to create model performance curves and heat maps. We demonstrated this method using an empirical model developed to predict the ecological condition of plant communities in riverine wetlands of the Appalachian Highland physiographic region, U.S.A. We assessed this model's transferability and generalizability across (1) riverine wetlands in the contiguous U.S.A., (2) wetland types in the Appalachian Highland physiographic region, and (3) wetland types in the contiguous U.S.A. With this methodology and a discussion of its critical steps, we set the stage for further inquiries into the development of consistent and transparent practices for model selection when transferring a model.

Technical note: Digital quantification of eye pigmentation of cattle with white faces.

Cancer of the eye in cattle with white faces occurs less frequently in cattle with pigmented eyelids. Corneoscleral pigmentation is related to eyelid pigmentation and occurrence of lesions that may precede cancer. Objectives of this study were to assess 1) variation in the proportion of eyelid and corneoscleral pigmentation in Hereford, Bos taurus, and Bos indicus crossbreds and 2) the occurrence of lesions with the presence of pigmentation in those areas. Hereford and Bos indicus crosses (Brahman or Nellore with Angus and Hereford and straightbred Brafords) and Bos taurus crosses (Angus-Hereford) were included in the study (n = 1,083). Eyelid pigmentation proportions were estimated by pixel quantification and were evaluated as total proportions and for upper and lower eyelids distinctly for each eye. Fixed effects included breed type, age categories, and sex of the animal. Lesion presence (1) or absence (0) was obtained by visual appraisal of image and was assumed to be binomially distributed. Eyelid pigmentation proportions (overall, upper, and lower eyelids) for Hereford ranged from 0.65 ± 0.03 to 0.68 ± 0.03 and were significantly lower than Bos indicus (range from 0.93 ± 0.02 to 0.95 ± 0.02) or Bos taurus (ranged from 0.88 ± 0.02 to 0.92 ± 0.02) crosses. Corneoscleral pigmentation in Hereford cows (0.17 ± 0.06) did not differ (P = 0.91) from Hereford calves and yearlings (0.16 ± 0.07). Bos indicus and Bos taurus crossbred cows had larger corneoscleral pigmentation (0.38 ± 0.05 and 0.48 ± 0.04 for left eyes and 0.37 ± 0.05 and 0.53 ± 0.04 for right eyes, respectively) than all calves (P < 0.001), and their corneoscleral pigmentations were greater than that of Hereford cows (P < 0.003). Bos indicus and Bos taurus cows had greater proportions of left eye corneoscleral pigmentation (0.38 ± 0.05 and 0.48 ± 0.04, respectively) than Hereford cows (0.17 ± 0.06) and all young animal breed types (P < 0.05). Right eye proportions differed for all cow groups (P < 0.05; 0.53 ± 0.04, 0.37 ± 0.05, and 0.17 ± 0.06). Among calves and yearlings, Hereford had a lower right eye corneoscleral pigmentation proportion (0.16 ± 0.07) than Bos taurus (P = 0.02). The lesion proportion for Hereford (0.08 ± 0.03) was significantly greater than that of either Bos indicus (0.01 ± 0.005) or Bos taurus (0.01 ± 0.003). Crossbreeding with Bos taurus or Bos indicus animals appears to increase eye pigmentation, which may help reduce the occurrence of cancer in eyes of cattle with white faces.

Gambusia quadruncus (Cyprinodontiformes: Poeciliidae): a new species of mosquitofish from east-central México.

Gambusia quadruncus n. sp., the llanos mosquitofish, is described from east-central México. The region inhabited by the species represents a hotspot of diversity of Gambusia, and G. quadruncus sometimes coexists with at least three congeners. The species differs from its closest relative, Gambusia affinis, in several characteristics with plausible effects on reproductive isolation, e.g. body size, body and fin morphology, male genital morphology (distal tip of gonopodium) and female anal spot morphology (colouration near the urogenital sinus). Moreover, combined analysis of mitochondrial and nuclear gene sequence data (c. 2158 total base pairs) indicates reciprocal monophyly of G. quadruncus and its sister species G. affinis, with levels of genetic divergence suggesting the two species diverged from one another over a million years ago. The origin of G. quadruncus may reflect a vicariant event associated with Pliocene orogenesis in the Tamaulipas Arch and a frontal section of the Sierra Madre Oriental (Lleran Mesas). Gambusia quadruncus inhabits a variety of freshwater habitats across several river drainages, with its range spanning at least 350 km from north to south, covering over 25 000 km(2). A key to aid identification of the species is provided.

Thrombotic complications of a basilar artery aneurysm in a young adult with Pompe disease.

BACKGROUND: Pompe disease or type 2 glycogen storage disease is an inherited condition that generally afflicts the heart and skeletal muscle. Nervous tissue involvement is known; however, the effect on cerebral vasculature is less well understood. CASE DESCRIPTION: The thrombotic complications of a fusiform basilar artery aneurysm in a young adult patient with Pompe disease is presented with complete CT, MRI, and angiographic findings. CONCLUSION: We suggest that in young adult patients with Pompe disease, MRA screening of intracerebral vessels may be considered with the goal of potentially diagnosing thrombotic and thromboembolic complications.

Complex phenotype-environment associations revealed in an East African cyprinid.

Environmental factors influence phenotypes directly, as well as indirectly via trait correlations and interactions with other environmental variables. Using nine populations of the African cyprinid Barbus neumayeri, we employed path analysis to examine direct, indirect and total effects of two environmental variables, water flow (WF) and dissolved oxygen (DO), on several morphological traits. WF and DO directly influenced relative gill size, body shape and caudal fin shape in manners consistent with a priori predictions. Indirect effects also played an important role in the system: (1) strong, oppositely signed direct and indirect effects of WF on body shape resulted in a nonsignificant total effect; (2) DO had no direct effect on body shape, but a strong total effect via indirect effects on gill size; (3) WF indirectly influenced gill size via effects on DO. Only through examination of multiple environmental parameters and multiple traits can we hope to understand complex relationships between environment and phenotype.

Final report of the FOPE II Pediatric Workforce Workgroup.

From the inception of the Future of Pediatric Education II (FOPE II) Project, it was acknowledged that any discussion of pediatric education would need to encompass a review of the pediatric workforce. This report looks at the current trends in pediatric workforce and draws some conclusions regarding future growth and composition. In addition to looking at demographic trends, ranging from geography to gender, the report explores influences including managed care, telemedicine, and others. Models for determining workforce needs are described and scenarios and projections are discussed. Pediatrics 2000;106(suppl):1245-1255; pediatric workforce.

Barriers to asthma care in urban children: parent perspectives.

BACKGROUND: Despite improved treatment regimens for asthma, the prevalence and morbidity from asthma are increasing, especially among underserved, minority children. OBJECTIVE: The purpose of this study was to identify barriers to the treatment of asthma among urban, minority children as perceived by parents. METHODS: Parents were recruited from 4 schools located in low-income, urban areas with high rates of asthma hospitalizations. Focus groups involving parents of children 5 to 12 years old with asthma were conducted using a standardized questionnaire. Parents' comments were analyzed to identify barriers, and 3 independent raters coded parents' comments to assess reliability of interpretation. RESULTS: Forty parents who represented 47 children participated in the focus groups. All parents described their racial background as black. Parents' average age was 36.8 years, 92% were females, 70% were nonmarried, and 38% had less than a high school education. Forty-five percent of children had intermittent or mild asthma and 55% had moderate to severe asthma. The most frequent types of barriers identified by parents were patient or family characteristics (43%), followed by environmental (28%), health care provider (18%), and health care system (11%). Parents were specifically concerned about the use, safety and long-term complications of medications, the impact of limitation of exercise on their child's quality of life, and their own quality of life. CONCLUSIONS: In contrast with the widespread beliefs that access to medical care, health insurance, and continuity of care are the major barriers to quality asthma care, the barriers most frequently reported by parents were related to patient and family characteristics, health beliefs, or to their social and physical environment. To improve asthma management and health outcomes for urban, minority children with asthma, it is critical to tailor education about asthma and its treatment, and address quality of life issues for both children and parents.

Determinants of counseling in primary care pediatric practice: physician attitudes about time, money, and health issues.

OBJECTIVES: To assess pediatrician goals and practice in preventive counseling, and to use social learning theory to examine physician attitudes about preventive health issues, time, and reimbursement to explain physician counseling behavior. DESIGN: Random sample survey of American Academy of Pediatrics fellows. PARTICIPANTS: A total of 1620 pediatricians were surveyed with a return rate of 72%. The 556 pediatricians who had finished training and who currently performed child health supervision were included. METHODS: Pediatricians were asked about their goals in 6 areas of health supervision: biomedical issues, development, behavior, family functioning, safety education, and supportive interpersonal interaction. They were also asked about the prevalence of counseling, importance of specific topics, their self-efficacy, outcome expectation in these areas, and their concerns about time and reimbursement for preventive counseling. RESULTS: Assurance of physical health and normal development were the most important goals of child health supervision among the pediatricians surveyed. Goals involving behavioral, family, and safety issues were less important and less likely to be addressed in practice. Most did not regularly discuss family stress, substance abuse, gun safety, and television. In these areas, physicians had less confidence they could provide guidance and lower expectation that they could prevent problems. Only 17% felt that they receive adequate reimbursement for preventive counseling. Most have adequate time (53%) and receive adequate respect (57%) for their preventive efforts. Physicians who were more concerned about time for preventive counseling reported less overall counseling (r = -0.28, P<.001). Concern about reimbursement was not associated with reported counseling. Multiple regression analysis found that the primary predictors of physician counseling were an issue's importance, a physician's perceived self-efficacy, and perceived effectiveness of counseling, while concerns about time and reimbursement were secondary. CONCLUSIONS: Physician goals in child health supervision were primarily biomedical, with psychosocial and safety issues of lesser importance. Concern about time for preventive counseling was associated with less reported counseling. Physician attitudes regarding the importance of a health issue and their confidence and effectiveness in counseling were more predictive of physician practice than their attitudes about time and reimbursement for preventive care.

Evaluation of primary care futures: a faculty development program for community health center preceptors.

PURPOSE: To assess the impact of a national series of faculty development workshops for community health center preceptors. METHOD: Two hundred and twenty-three community health center preceptors from a variety of disciplines attended one of five workshops conducted in different regions of the country. The workshops emphasized active learning using role-play to provide skills in educational planning, teaching styles, evaluation, and feedback. The preceptors were evaluated before and immediately after the workshop, and again three months later. They were also asked to assess the quality of the workshop. RESULTS: The preceptors demonstrated significant increases in the use of five of seven teaching concepts while analyzing a role-play interaction. In addition, there were significant positive, immediate changes in familiarity with nine of 11 concepts, which were retained for at least three months. The preceptors also reported that they continued to use six of the effective teaching behaviors they had learned three months after the workshop. They were extremely positive in their assessments of the workshops. CONCLUSION: This preliminary study suggests that preceptors from a variety of backgrounds can improve their teaching knowledge and skills by participating in a brief faculty development program that emphasizes active learning.

Costs and limits of phenotypic plasticity.

The costs and limits of phenotypic plasticity are thought to have important ecological and evolutionary consequences, yet they are not as well understood as the benefits of plasticity. At least nine ideas exist regarding how plasticity may be costly or limited, but these have rarely been discussed together. The most commonly discussed cost is that of maintaining the sensory and regulatory machinery needed for plasticity, which may require energy and material expenses. A frequently considered limit to the benefit of plasticity is that the environmental cues guiding plastic development can be unreliable. Such costs and limits have recently been included in theoretical models and, perhaps more importantly, relevant empirical studies now have emerged. Despite the current interest in costs and limits of plasticity, several lines of reasoning suggest that they might be difficult to demonstrate.

Clinical teaching improvement: past and future for faculty development.

Faculty development programs have focused on the improvement of clinical teaching for several decades, resulting in a wide variety of programs for clinical teachers. With the current constraints on medical education, faculty developers must reexamine prior work and decide on future directions. This article discusses 1) the rationale for providing faculty development for clinical teachers, 2) the competencies needed by clinical teachers, 3) the available programs to assist faculty to master those competencies, and 4) the evaluation methods that have been used to assess these programs. Given this background, we discuss possible future directions to advance the field.

Primary care pediatrics in Italy: eighteen years of clinical care, research, and teaching under a national health service system.

This article reviews how Italian National Health Service (NHS) pediatricians have tried to fulfill the obligations of modern primary care providers in a managed care environment, with special reference to the experience of the Veneto region in Italy and compares this situation with the present changes of the health system in the United States. Italian NHS primary care pediatricians work independently in their offices, providing acute and chronic patients to all children 0 to 14 years old: NHS primary care physicians, including 7000 pediatricians, contract directly with the government for the care of patients through a capitated reimbursement system. Twenty-nine independent associations of community pediatricians have been formed with the primary goal to pursue research and education in primary care pediatrics, in addition to traditional care. Several multicenter collaborative research studies at the national level have been organized and four university residency programs are training their residents in community-based pediatricians' offices also, giving priority to activities specific to ambulatory practice and follow the suggestion of an Italian work group on ambulatory pediatric training. The NHS has allowed the Italian pediatrician to focus on patient care and education rather than business. Computerization has been applied to the practice of medicine through the development of electronic medical records, particularly in the Veneto region. This technology allows combining effective clinical care with outcome researches and facilitates continuing medical education and residents' training programs. Italian primary care NHS pediatricians have tried to identify and address patient's needs as well as the needs of a primary care provider in a managed care system. Recent and possible future modifications in the health system in the United States and in Italy need to be examined to learn from similarities and differences.

The University of Massachusetts Medical Center office-based continuity experience: are we preparing pediatrics residents for primary care practice?

OBJECTIVE: Surveys of residency graduates and employers have suggested that residency programs do not prepare residents well for practice. Since 1988, pediatric residents at the University of Massachusetts have been paired one-on-one with an office-based pediatrician for their 3-year continuity experience. This survey was conducted to determine if graduates of such a program are prepared to enter pediatric practice. METHODOLOGY: Graduates of the program from 1991 through 1995 who entered primary care practice were surveyed about their preparedness for practice. The questionnaire was also sent to the residents' first employers. The 32 questions were directed to overall sense of preparedness, ability to manage the pace of practice, common illnesses, common behavior problems, anticipatory guidance, office management, and subspecialty problems. RESULTS: Data from all 25 residents who entered practice and the employers of 20 of the 25 residents were obtained and analyzed. Both groups rated overall resident preparedness to be "well-prepared" or "very well-prepared" and gave high scores on working at the pace of practice, diagnosing and treating common illnesses, diagnosing and treating common behavior problems, and providing anticipatory guidance. Areas in which residents were considered to be less well-prepared included anticipatory guidance about nutrition, managing problems by telephone, office management, gynecology, and orthopedics. CONCLUSIONS: The results suggest that continuity experiences in office practices are associated with preparation for the pace and types of visits that occur commonly in primary care practice, abilities which previous surveys of residency alumni and employers have found lacking. Some areas may benefit from a formal curriculum which may be implemented in the office practice, at the medical center, or at both sites. Preceptors may benefit from faculty development and continuing medical education that is directed not only at teaching skills but also at content areas which were not addressed in their own residencies.

Faculty development for community practitioners.

Developing the academic skills of the individuals who will serve as educators and role models in the community is critical to pediatric resident education in community settings. The main focus of any faculty development program must be on teaching, although for a subset of individuals, the development of research skills should also be a consideration. The three key elements that must be considered for an effective faculty development program include: (1) creating a culture of mutual respect between full-time and community faculty; (2) basing the program on sound principles of education theory, especially adult learning theory, using appropriately trained faculty; and (3) establishing ongoing institutional financial and philosophical support. Effectively addressing these elements should create a faculty development program that will help the community practitioner become an effective role model and practitioner- preceptor-educator.