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1.
J Contam Hydrol ; 61(1-4): 191-202, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12598104

ABSTRACT

A program of in situ experiments, supported by laboratory studies, was initiated to study diffusion in sparsely fractured rock (SFR), with a goal of developing an understanding of diffusion processes within intact crystalline rock. Phase I of the in situ diffusion experiment was started in 1996, with the purpose of developing a methodology for estimating diffusion parameter values. Four in situ diffusion experiments, using a conservative iodide tracer, were performed in highly stressed SFR at a depth of 450 m in the Underground Research Laboratory (URL). The experiments, performed over a 2 year period, yielded rock permeability estimates of 2 x 10(-21) m(2) and effective diffusion coefficients varying from 2.1 x 10(-14) to 1.9 x 10(-13) m(2)/s, which were estimated using the MOTIF code. The in situ diffusion profiles reveal a characteristic "dog leg" pattern, with iodide concentrations decreasing rapidly within a centimeter of the open borehole wall. It is hypothesized that this is an artifact of local stress redistribution and creation of a zone of increased constrictivity close to the borehole wall. A comparison of estimated in situ and laboratory diffusivities and permeabilities provides evidence that the physical properties of rock samples removed from high-stress regimes change. As a result of the lessons learnt during Phase I, a Phase II in situ program has been initiated to improve our general understanding of diffusion in SFR.


Subject(s)
Models, Theoretical , Silicon Dioxide/chemistry , Diffusion , Geological Phenomena , Geology , Permeability , Radioactive Waste , Waste Management
2.
Clin Orthop Relat Res ; (392): 349-57, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11716406

ABSTRACT

Idiopathic scoliosis is a highly prevalent disorder, familial in nature, with marked clinical variability. The purpose of this study was to characterize idiopathic scoliosis in a large series of families to be used for a genome-wide search. One hundred thirty-one multigenerational families (892 individuals) with at least two affected individuals were studied. Data obtained included curve pattern, treatment, and back pain. Maximum curvature as a continuous variable was evaluated using t tests for dichotomous characteristics and linear correlation for continuous variables. An analysis of familial loading was done. Four hundred forty-four individuals were classified as affected (82% female; 18% male). The right thoracic and left lumbar curves had the highest mean curvature (49 degrees). Mean curve size was greater in individuals with back pain. Back pain was most prevalent in the right thoracic and left lumbar curve pattern. The Pearson correlation coefficient between the number of affected family members and the maximum degree of curvature was 0.16, suggesting that the greater the lateral curvature, the higher the proportion of family members affected with scoliosis. The sample population is consistent with those of previous studies in relation to gender and curve size. Statistically, the familial nature of this disorder is supported.


Subject(s)
Scoliosis/genetics , Biomechanical Phenomena , Female , Humans , Male , Pedigree , Scoliosis/physiopathology
7.
Heart Lung ; 29(6): 438-45, 2000.
Article in English | MEDLINE | ID: mdl-11080325

ABSTRACT

Women's Initiative for Nonsmoking (WINS) is a randomized clinical trial designed to test the efficacy of a nurse-managed smoking cessation and relapse prevention intervention designed specifically for women. The WINS intervention is rooted in social learning theory, specifically that of self-efficacy. It is a multimedia approach that provides education, counseling, and telephone follow-up that meet the smoking cessation intervention guidelines established by the Agency for Health Care Policy and Research. The WINS intervention has been successfully implemented in more than 140 women and has proven to be feasible and well accepted by both the women and their health care providers. Although the intervention in the protocol-driven randomized clinical trial was begun in the hospital, it is anticipated that nurses in any setting, inpatient or outpatient, who serve populations at risk for cardiovascular disease, peripheral vascular disease, lung cancer, or pulmonary disease could successfully provide the intervention.


Subject(s)
Cardiovascular Diseases/nursing , Smoking Cessation/methods , Cardiovascular Diseases/etiology , Female , Follow-Up Studies , Humans , Nurse Clinicians , San Francisco , Smoking/adverse effects , Treatment Outcome
8.
J Bone Joint Surg Am ; 82(8): 1157-68, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10954107

ABSTRACT

Current population studies characterize idiopathic scoliosis as a single-gene disorder that follows the patterns of mendelian genetics, including variable penetrance and heterogeneity. The role of melatonin and calmodulin in the development of idiopathic scoliosis is likely secondary, with indirect effects on growth mechanisms. Reported abnormalities of connective tissue, skeletal muscle, platelets, the spinal column, and the rib cage are all thought to be secondary to the deformity itself. Although no consistent neurological abnormalities have been identified in patients with idiopathic scoliosis, it is possible that a defect in processing by the central nervous system affects the growing spine. The true etiology of idiopathic scoliosis remains unknown; however, it appears to be multifactorial.


Subject(s)
Scoliosis/etiology , Biomechanical Phenomena , Blood Platelets/pathology , Growth , Humans , Melatonin/physiology , Models, Theoretical , Muscle, Skeletal/abnormalities , Pedigree , Research , Scoliosis/genetics
9.
Arch Intern Med ; 159(22): 2739-42, 1999.
Article in English | MEDLINE | ID: mdl-10597765

ABSTRACT

The treatment of chronic disease is often complicated by the coexistence of multiple medical conditions and by the presence of social and psychological impediments. The needs posed by patients with chronic disease are overwhelming the capacity of the American health care system. Alternative disease management systems that rely on specially trained nurse case managers to implement detailed clinical protocols, including drug algorithms, have shown efficacy in managing chronic medical conditions, singly and in combination. By fostering integration of care across subspecialty and medical-social boundaries, such systems enable treatment of the patient with disease(s), not simply treatment of disease(s) in the patient. Working closely with primary care physicians, often by telephone-mediated interaction with patients, nurse case managers may take an expanded role in meeting the challenges posed by chronic disease.


Subject(s)
Case Management , Chronic Disease , Delivery of Health Care , Primary Health Care , Chronic Disease/nursing , Humans , Morbidity , United States
10.
Foot Ankle Int ; 20(7): 456-60, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10437930

ABSTRACT

Pes planus is a term frequently used in describing flatfoot; however, no study has objectively defined flatfoot. We evaluated the single leg stance footprint of 40 feet in 21 people with no history of foot problems, using pressure-sensitive film and a Harris mat. The medial and lateral aspects of the forefoot, midfoot, and hindfoot were assessed. The midfoot was further analyzed by dividing the medial midfoot force by the total midfoot force. The mean medial midfoot force/total midfoot force was 11.1% (SD = 6.5%). Pes planus was defined as the medial midfoot force/total midfoot force > 24.0% (mean + 2 SD). A population associated with pes planus (124 feet in 63 patients with Marfan syndrome) was then evaluated in the same fashion. Although the mean medial midfoot force/total midfoot force was not statistically different (16.0%), a distinct group of patients (25%) had forces that were outside the range of normal midfoot forces.


Subject(s)
Flatfoot/physiopathology , Foot/physiology , Adult , Biomechanical Phenomena , Child, Preschool , Dermatoglyphics , Flatfoot/diagnosis , Foot/physiopathology , Humans , Infant , Marfan Syndrome/physiopathology , Pressure , Reference Values , Sensitivity and Specificity
11.
Orthop Clin North Am ; 30(3): 343-52, vii, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10393760

ABSTRACT

Adolescent idiopathic scoliosis is a highly prevalent disorder of the spine, occurring in phenotypically normal individuals for unknown reasons. The role of genetic factors in this condition has been widely documented through clinical observations and population studies. Multiple areas of research, including connective tissue, neuromotor mechanisms, hormonal system, and biomechanics, have been explored for a potential relationship to the cause of idiopathic scoliosis; however, no clear evidence supports any one area as a etiologic factor of this disorder. The main difficulty of most investigations is to determine whether the observed abnormalities are primary or secondary features in the scoliotic deformity. It is hoped that continued research efforts will aid in the understanding of this disorder in an effort to improve the ability to assign a more specific prognosis.


Subject(s)
Scoliosis/physiopathology , Adolescent , Biomechanical Phenomena , Humans , Scoliosis/etiology , Scoliosis/genetics
12.
J Consult Clin Psychol ; 67(1): 19-27, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10028205

ABSTRACT

This study extends the results of a large randomized clinical trial of a multicomponent in-hospital smoking cessation intervention for general hospitalized smokers by examining subgroups of patients who responded to the intervention. The results, obtained using signal detection analysis, produced 6 subgroups of patients with varying degrees of intervention responsiveness. The subgroup most responsive was marked by 100% confidence to quit smoking at baseline. Among patients with less than 100% confidence, confidence interacted with age, depressed mood scores, addiction scores, and alcohol intake to discriminate 5 additional subgroups. Discussion focuses on how this information can be used in clinical decision making to treat subpopulations of smokers and directs attention to possible areas of underlying biopsychosocial processes that may interact to affect successful long-term cessation.


Subject(s)
Inpatients , Signal Detection, Psychological , Smoking Cessation/methods , Tobacco Use Disorder/therapy , Age Factors , Aged , Alcohol Drinking , Female , Hospitals, Voluntary/organization & administration , Humans , Logistic Models , Male , Managed Care Programs/organization & administration , Middle Aged , Psychiatric Status Rating Scales , Smoking Cessation/psychology , Treatment Outcome
14.
J Pediatr Orthop ; 18(6): 755-9, 1998.
Article in English | MEDLINE | ID: mdl-9821131

ABSTRACT

The feet of Marfan patients are typically described as pes planovalgus. We evaluated the single-leg-stance footprint of 124 feet in 63 patients with the Marfan syndrome by using pressure-sensitive film and a Harris mat. Forty feet in 21 people with no history of foot problems were evaluated as normal controls. The medial and lateral aspects of the fore-, mid-, and hindfoot were assessed. The midfoot was further analyzed by dividing the medial midfoot force by the total midfoot force. The mean medial midfoot force/total midfoot force (MM/TM) in the control population was 11.1% (SD, 6.5%). Pes planus was defined as the MM/TM force > 24.0% (mean + 2 SD). The mean MM/TM force in the Marfan group was not statistically different (16.0%) from controls. The distribution, however, revealed two distinct types of weight-bearing patterns. Of the Marfan group, 74.8% had medial forces within the standard distribution of the normal control population. Only 25.2% of the Marfan patients had forces that were outside the range of normal midfoot forces and were defined as pes planus. Analysis of the patient's ligamentous laxity and the foot function in the Marfan population revealed no statistically significant correlation to the type of weight-bearing pattern of the foot.


Subject(s)
Foot , Marfan Syndrome , Adult , Biomechanical Phenomena , Foot/pathology , Foot/physiopathology , Humans , Marfan Syndrome/pathology , Marfan Syndrome/physiopathology , Prospective Studies
15.
Pediatrics ; 101(5): E4, 1998 May.
Article in English | MEDLINE | ID: mdl-9565437

ABSTRACT

OBJECTIVE: To document the practices and attitudes of the US physician members of the Society for Adolescent Medicine (SAM) regarding adolescent abortion and contraception, as well as physician willingness to prescribe medical abortion if approved by the Food and Drug Administration (FDA). DESIGN: Cross-sectional questionnaire survey. Participants. The entire physician membership of SAM (N = 1001) was surveyed. A total of 713 physicians responded, with 668 usable surveys yielding an adjusted response rate of 70%. RESULTS: Of the respondents, 81% were trained as pediatricians; 58% had additional adolescent medicine training. Ninety-six percent prescribed contraception for their patients. Sixty-one percent of respondents identified abortion as an option for pregnant adolescents in all circumstances, whereas 4% believed abortion should never be an option. Eighty-nine percent referred their patients for abortions; 90% were aware of medications to induce abortions medically. If these medications (methotrexate and misoprostol, RU-486) were FDA-approved, 42% would prescribe them for their patients; 34% were unsure. Fifty-four percent believed if medical abortions were routinely available, they should be available from primary care physicians. Physicians were significantly more likely to consider prescribing medical abortions if the physician were female, offered postcoital contraception, performed Norplant insertions, referred adolescents for abortions, or performed postabortion medical checkups. Physicians were no more likely to consider prescribing medical abortions according to physician age, specialty training, or date of residency training. Religious affiliation per se was not associated with likelihood of prescribing medical abortions, but Catholic physicians were significantly less likely to consider prescribing medical abortions. CONCLUSIONS: Virtually all SAM physician respondents (96%) reported that abortion for pregnant adolescents should be available under some circumstances. Forty-two percent would prescribe medical abortion if the medications were FDA-approved, suggesting that medical abortion would potentially be available to adolescents from a larger group of physicians than is currently available.


Subject(s)
Abortion, Induced , Adolescent Medicine/statistics & numerical data , Attitude of Health Personnel , Abortifacient Agents , Abortion, Induced/psychology , Abortion, Induced/statistics & numerical data , Adolescent , Adult , Cross-Sectional Studies , Female , Humans , Male , Medicine/statistics & numerical data , Middle Aged , Practice Patterns, Physicians' , Pregnancy , Religion and Medicine , Sex Factors , Societies, Medical , Specialization , Surveys and Questionnaires , United States
17.
J Cardiopulm Rehabil ; 17(3): 157-62, 1997.
Article in English | MEDLINE | ID: mdl-9187981

ABSTRACT

BACKGROUND: This study examined the effects of a nurse-case-managed, multifactorial, risk-reduction program on psychological distress among patients after myocardial infarction (MI). METHODS: Five hundred eighty-five men and women aged 70 years or younger, who were hospitalized for acute MI in one of five San Francisco Bay Area hospitals, were randomized to receive a nurse-managed, home-based, multifactorial risk-reduction program (n = 293) or usual care (n = 292). The program, which began in the hospital, included a brief screen for five areas of psychological distress with further evaluation if indicated, monitoring during the follow-up phone calls, and referral for mental health treatment if needed. Patients were assessed with single-item scales at baseline, and at 6 and 12 months. Separate analyses were performed for patients with moderate-to-severe levels on the psychological distress domains and for those with low levels. RESULTS: There was a significant reduction in the psychological distress variables for all patient groups between baseline and 12 months. The program had a significant effect on reducing anxiety in the patient group with low levels of anxiety and reducing anger in the patient group with frequent episodes of anger but, overall, the treatment and control groups showed equal levels of improvement. CONCLUSION: Among patients post-MI without complications, psychological distress decreases significantly during the 12 months after MI.


Subject(s)
Case Management/organization & administration , Home Care Services/organization & administration , Myocardial Infarction/psychology , Stress, Psychological/nursing , Stress, Psychological/prevention & control , Aged , Female , Humans , Longitudinal Studies , Male , Nursing Assessment , Psychiatric Status Rating Scales , Risk Factors , Stress, Psychological/etiology
18.
Arch Intern Med ; 157(4): 409-15, 1997 Feb 24.
Article in English | MEDLINE | ID: mdl-9046892

ABSTRACT

BACKGROUND: Few research studies have evaluated the effectiveness of smoking interventions in hospitalized patients. This randomized controlled trial compared the efficacy of 2 smoking cessation programs in patients hospitalized in 4 community hospitals in a large health maintenance organization within the San Francisco Bay Area in California. METHODS: Patients were randomly assigned to usual care (n = 990), nurse-mediated, behaviorally oriented inpatient counseling focused on relapse prevention with 1 postdischarge telephone contact (minimal intervention, n = 473), or the same inpatient counseling with 4 postdischarge telephone contacts (intensive intervention, n = 561). The main outcome measure, smoking cessation rate, was corroborated by plasma cotinine determination or family confirmation, 1 year after enrollment. RESULTS: At 1 year smoking cessation rates were 27%, 22%, and 20% for intensive intervention, minimal intervention, and usual care groups, respectively (P = .009 for intensive vs usual care). Subgroup analyses by diagnosis revealed that the odds of cessation among patients with cardiovascular disease or other internal medical conditions were greater among those receiving the intensive intervention than among their counterparts receiving usual care (odds ratios, 1.6 and 2.0, respectively). CONCLUSIONS: A multicomponent smoking cessation program consisting of physician advice; in-hospital, nurse-mediated counseling; and multiple postdischarge telephone contacts was effective in increasing smoking cessation rates among hospitalized smokers. Hospital-wide smoking cessation programs could substantially increase the effectiveness of hospital smoking bans.


Subject(s)
Smoking Cessation/methods , California , Female , Hospitalization , Humans , Male , Odds Ratio , Tobacco Use Disorder/complications , Treatment Outcome
19.
Am J Med ; 102(2A): 43-9, 1997 Feb 17.
Article in English | MEDLINE | ID: mdl-9217586

ABSTRACT

At least one third of hospital admissions for heart failure result from noncompliance with therapeutic regimens, both dietary and pharmacologic. In chronic diseases, noncompliance with both lifestyle modification and medication regimens is a major health problem. Patients frequently stop taking their medications because they consider them ineffective or because they experience unpleasant side effects. In asymptomatic conditions, patients may believe they do not need the medication and may not even fill their prescription. If they do obtain the medications, they may forget to take them regularly. Educational efforts and behavioral techniques can improve patient compliance in chronic, asymptomatic conditions, but one of the most effective strategies remains improved patient-physician communication.


Subject(s)
Chronic Disease/therapy , Patient Compliance , Health Behavior , Health Education/methods , Humans , Life Style , Physician-Patient Relations
20.
J Am Diet Assoc ; 97(2): 146-50, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9020241

ABSTRACT

OBJECTIVE: To describe the development of a computer-based system for dietary management of hyperlipidemia and to evaluate its efficacy for lowering plasma cholesterol level. DESIGN: Using a stepwise approach, we developed and tested a three-part self-management system in five consecutive clinical studies. Each study assessed plasma cholesterol levels before and after dietary intervention using the system. These studies enabled progressive refinement of (a) a food frequency questionnaire used to assess food intake in the preceding month; (b) computer-generated progress reports, based on questionnaire responses, offering dietary change subgoals and strategies for change; and (c) a dietary workbook providing detailed information on how to achieve goals. SUBJECTS/SETTING: Persons with hyperlipidemia (n=814) were enrolled from worksite and clinical settings in the San Francisco Bay area of California. The attrition rate after randomization was 5%. INTERVENTION: Elements of the dietary intervention evolved in response to the results of five clinical studies. In each study, patients underwent a form of baseline assessment of dietary intake followed by counseling/instruction by various means. Follow-up dietary assessments were provided at specific intervals to facilitate subjects' progress toward their dietary goals. A dietary workbook provided the detailed instruction required to implement the recommendations contained in the periodic progress reports. STATISTICAL ANALYSES PERFORMED: Changes in plasma cholesterol level were measured by paired and unpaired t tests. The relationship between the reported reduction in dietary fat and cholesterol level assessed by food frequency questionnaires and the directly measured change in plasma cholesterol level was measured by multiple linear regression. RESULTS: The three major elements of the final computerized system (food frequency questionnaires, computer-generated progress reports, and dietary workbook) were developed and refined in the course of the five clinical studies. Reductions in total plasma cholesterol level of 5.0% to 6.5% achieved by participants in all five studies were consistent with self-reported reductions in intake of dietary saturated fat and cholesterol. Therefore, the computerized self-management system appears to be an effective tool for reducing plasma cholesterol levels. APPLICATIONS/CONCLUSIONS: A computer-based system for dietary self-management of hyperlipidemia, implemented by mail, was effective in short-term studies. This self-management system can potentially provide health-promoting services to large numbers of people at low cost.


Subject(s)
Hyperlipidemias/diet therapy , Therapy, Computer-Assisted , Adult , Cholesterol/blood , Cholesterol, Dietary/administration & dosage , Diet Records , Dietary Fats/administration & dosage , Evaluation Studies as Topic , Feedback , Humans , Linear Models , Middle Aged , Patient Education as Topic , Self Care , Surveys and Questionnaires
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