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Soil water repellency (SWR) is a widespread phenomenon that influences patterns of soil wetting, runoff, evapotranspiration and availability of water for plants. In natural ecosystems there is emerging evidence that some plants can take advantage of non-uniform wetting patterns, leading to the emergence of co-evolutionary behaviour. In this review, SWR is considered in terms of five spheres of influence. Given the presence of hydrophobic organic material in the biosphere, the strength, severity and persistence of SWR is influenced by properties at the surface of the lithosphere and prevailing conditions in the atmosphere and hydrosphere. These in turn, can be modified by activities in the anthroposphere. This review thus examines the strength, severity and persistence of non-wetting behaviour with reference to these five spheres of influence and also the interactions between the spheres. It is focused on (i) how SWR is characterised to provide insight into how different measurement techniques have specific operational ranges, (ii) how SWR has developed as an indirect consequence of evolution in natural ecosystems and (iii) how feedbacks across the different spheres have emerged. It demonstrates that management and restoration of natural ecosystems with water repellent soils is very different from management of productive crops in monocultural agricultural systems, controlled in the anthroposphere.

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Since the first introduction of implantable pacemaker approximately 50 years ago, these devices have become increasingly more common and more complex. It is estimated that there are approximately 1 million patients with implanted pacemakers in the United States and, with an aging population, the number of pacemakers is certain to increase. This review focuses on basics of pacemaker function as well as the common rhythm disturbance issues and other clinical syndromes that the emergency physician is likely to encounter.

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BACKGROUND: This study evaluated the effect of primary care providers' adherence with the AHCPR Smoking Cessation Guideline after receiving a multicomponent intervention. METHODS: A quasi-experimental study with one intervention and one control team was conducted in a southeastern Veterans Affairs Medical Center primary care setting. During phase I, chart reviews were conducted to measure baseline provider adherence and documentation of the four A's (ask, advise, assist, arrange). In phase II, the intervention team received a single educational session on the AHCPR Guideline, four A's, and tobacco dependence treatment. This was followed by chart reviews of patients seen 4 to 8 weeks after the educational intervention to measure provider adherence and documentation of the four A's. During phase III, the intervention team received individual and team feedback from the chart reviews in phases I and II and booster education on the AHCPR Guideline. Chart reviews were conducted from patient visits 4 to 8 weeks after the feedback and booster education to determine provider adherence and documentation of the four A's. RESULTS: A nested repeated measures two-factor analysis of variance was performed for each of the following outcomes: ask, advise, assist, and arrange. Data analyses revealed that both the control and the intervention teams had 100% compliance in asking the patient about smoking status. There was a prestudy implementation of the vital sign stamp that included smoking status in this setting. Education on tobacco dependence and the AHCPR Guideline had no significant impact on provider performance with the advisement, assistance, and arrangement of follow-up. However, significant improvements occurred in the intervention team in the advisement (P = 0.05), assistance (P = 0.001), and arrangement of follow-up (P = 0.001) phase after individual and team feedback was provided. This research supports the fact that feedback impacts individuals and team performances and facilitated positive system changes to improve provider adherence with the AHCPR recommendations in treating tobacco dependence.

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OBJECTIVES: The purpose of this study was to assess whether the immediate availability of serum markers would increase the appropriate use of thrombolytic therapy. BACKGROUND: Serum markers such as myoglobin and creatine kinase, MB fraction (CK-MB) are effective in detecting acute myocardial infarction (AMI) in the emergency setting. Appropriate candidates for thrombolytic therapy are not always identified in the emergency department (ED), as 20% to 30% of eligible patients go untreated, representing 10% to 15% of all patients with AMI. Patients presenting with chest pain consistent with acute coronary syndrome were evaluated in the EDs of 12 hospitals throughout North America. METHODS: In this randomized, controlled clinical trial, physicians received either the immediate myoglobin/CK-MB results at 0 and 1 h after enrollment (stat) or conventional reporting of myoglobin/CK-MB 3 h or more after hospital admission (control). The primary end point was the comparison of the proportion of patients within the stat group versus control group who received appropriate thrombolytic therapy. Secondary end points included the emergent use of any reperfusion treatment in both groups, initial hospital disposition of patients (coronary care unit, monitor or nonmonitor beds) and the proportion of patients appropriately discharged from the ED. RESULTS: Of 6,352 patients enrolled, 814 (12.8%) were diagnosed as having AMI. For patients having AMI, there were no statistically significant differences in the proportion of patients treated with thrombolytic therapy between the stat and control groups (15.1% vs. 17.1%, p = 0.45). When only patients with ST segment elevation on their initial electrocardiogram were compared, there were still no significant differences between the groups. Also, there was no difference in the hospital placement of patients in critical care and non- critical care beds. The availability of early markers was associated with more hospital admissions as compared to the control group, as the number of patients discharged from the ED was decreased in the stat versus control groups (28.4% vs. 31.5%, p = 0.023). CONCLUSIONS: The availability of 0- and 1-h myoglobin and CK-MB results after ED evaluation had no effect on the use of thrombolytic therapy for patients presenting with AMI, and it slightly increased the number of patients admitted to the hospital who had no evidence of acute myocardial necrosis.

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PURPOSE/OBJECTIVES: To describe an intensive nurse practitioner (NP)-managed smoking cessation clinic that evolved from a primary-care quality-management initiative. DATA SOURCE: Published articles, abstracts, books, clinical experience, and clinical data. DATA SYNTHESIS: Smoking continues to be the leading cause of preventable deaths in the United States and accounts for 87% of all lung cancers. Although smoking is responsible for nearly 30% of all cancer deaths, smoking prevalence rates remain stagnant in adults and are continuing to increase in adolescents. Twenty-five percent of all Americans smoke. An NP-managed clinic was developed within a large teaching hospital located in the southeastern United States based on the Agency for Health Care Policy and Research guideline for smoking cessation. The clinic provided effective smoking cessation interventions that can be replicated by experienced nurses with a smoking cessation background. All nurses have opportunities to assist patients to stop smoking through brief counseling and minimum interventions. CONCLUSIONS: Nurses can effectively manage an intensive smoking cessation clinic that is utilized by the interdisciplinary team to treat referrals. Cessation rates were high because therapies combined intensive behavioral sessions and pharmacologic approaches rather than either single modality. IMPLICATIONS FOR NURSING PRACTICE: Nurses can replicate this practice in a variety of healthcare settings. Innovations in clinical practice often facilitate research studies to further define effective approaches for smoking cessation. Nurses need to identify and target smoking as the serious health problem it is and conduct much-needed research on cessation approaches within the inpatient and outpatient settings.

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OBJECTIVE: To compare in-hospital time uses by first-postgraduate-year (PGY1) residents during rotations in emergency medicine (EM), internal medicine (IM), and surgery (S). This article reports the clinical components of residency time use. METHODS: A cross-sectional, observational study of the clinical activities of EM PGY1 residents was performed while the residents were on duty during the three specialty rotations. The activities were recorded by an observer using a log with predetermined categories for clinical activities. A time-blocked, convenience sample of resident shifts was observed for each service rotation. The sample was proportional to the total number of hours for which a PGY1 resident was expected to be in the hospital during a rotation on that service. No attempt was made to sample the same resident at all time periods or on all rotations. Proportions were compared by chi2; alpha = 0.0001. RESULTS: Twelve PGY1 residents were observed for a total of 166 hours on S, 156 hours on IM, and 120 hours on EM. These hourly amounts were representative of a typical two-week span of service on each rotation for the residents. On average, the residents spent 57% of their time on clinical or service-oriented activities. During EM and IM rotations, the residents spent most of their time performing clinical information gathering and engaging in case management and data synthesis (52% of total clinical effort). Within this category, residents on EM were more involved with case discussion and review of ancillary test results than on IM (34% vs 20% of time in this category). Conversely, proportionately less time in this category was devoted to documentation on the EM vs IM rotation (56% vs 80%; p < 0.0001). The greatest opportunity to perform procedures was on the S rotation (31% of total clinical time vs 6% for other specialties; p < 0.0001). CONCLUSION: Awareness of the clinical activities performed on PGY1 rotations can help residency directors anticipate educational needs to balance their residents' experience. Since 29% and 42% of total clinical time on PGY1 EM and IM rotations, respectively, is focused on documentation, efforts to enhance charting skills and efficiency are warranted. Also, efforts to enhance PGY1 procedural experience outside of the S rotation appear warranted.

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Smoking is the single most preventable cause of death in our society. Each year, cigarettes kill more Americans than AIDS, alcohol, car accidents, fires, illegal drugs, murders, and suicides combined. An estimated 46 million adults in the United States smoke--28% of all men and 23.5% of all women. Seventy percent of Americans who smoke say that they would like to quit. Additionally, 70% who smoke visit a healthcare provider each year. Unfortunately, half of these who seek health care each year say they have never been advised to quit smoking or provided specific strategies to be successful at quitting. In 1996, the Agency for Health Care Policy and Research (AHCPR) published smoking cessation materials in several formats that target different audiences. This article describes the significant health problems of smoking and the AHCPR publications for smoking cessation. Providers are encouraged to identify smoking cessation as a priority and incorporate the AHCPR guidelines into routine health care for all patient encounters.

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OBJECTIVE: To compare amounts of in-hospital time use by PGY1 residents during rotations in emergency medicine (EM), internal medicine (IM), and surgery. This article reports the general study methodology and focuses on the educational aspects of residency time use. METHODS: A cross-sectional, observational study of the activities of EM PGY1 residents was performed while the residents were on duty during the 3 specialty rotations. The activities were recorded by an observer using a log with predetermined categories for clinical/service, educational, and personal areas. A time-blocked, convenience sample of resident shifts was observed for each service rotation. The sample was proportional to the total number of hours for which a PGY1 resident was expected to be in the hospital during a rotation on that service. No attempt was made to sample the same resident at all time periods or on all rotations. RESULTS: Twelve PGY1 residents were observed for a total of 166 hours on surgery, 156 hours on IM, and 120 hours on EM. These hourly amounts were representative of a typical 2-week span of service on each rotation for the residents. On average, the residents spent 57% of their time on clinical or service-oriented activities, 24% on educational activities, and 19% on personal activities. The proportions of time devoted to the 3 major areas were similar for the 3 rotations. In all 3 rotations, the largest proportion of time was spent on patient-focused education (81% to 92% of total educational time). Only 2% to 11% of educational time was devoted to self-education. Within the patient-focused education category, proportionately less resident time with faculty occurred on the surgery rotation than on the EM and IM rotations (18% vs 30% and 27%, respectively). CONCLUSION: The general breakdowns of clinical/service, educational, and personal time use by PGY1 residents are proportionately similar for the 3 service rotations. Patient-focused education is the primary mode of education for all services. In-hospital, self-education time is limited. Clinical teaching is largely by nonfaculty. The educational implications of these findings are discussed.

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This research investigated the fatigue life (ie, the number of cycles of a given stress that can be sustained by a sample prior to catastrophic failure) of metal ceramic soldering. One metal ceramic alloy was joined using four postceramic solders and one preceramic solder. All specimens received appropriate heat treatment simulating ceramic application although no porcelain was applied. Five specimens were fabricated for each solder type, and a 35,000 psi (241.4 MPa) fatigue stress was applied to each solder joint during specimen testing. The test variable was the number of stress cycles required to fail each specimen. The postceramic solders exhibited significantly higher fatigue lives than did the preceramic solder. Scanning electron microscope analysis showed that the preceramic solder not only exhibited a larger grain size, but also showed micropores between these grains.

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Three dental adhesives were used to chemically bond three dental veneering resins to a nickel-chromium alloy and a 52% gold alloy. As a control, all three veneering resins were applied directly to the aluminum-oxide-abraded surface without using an adhesive. The various combinations were subjected to a tensile load, and the tensile bond strength and failure location were recorded. The results indicated that the adhesives provided a statistically significant bond between the resin and the alloys.

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A three-dimensional distortion analysis was made of seven indexing-investment systems and six indexing-remount systems. Measurements were made to within +/- 0.005 mm with a Nikon Profile Projector and a linear variable differential transformer (LVDT); distortions (linear and rotational) were calculated by means of a PDP 11/40 computer system. Mean vector displacements, square root deltaX2 + deltaY2 + deltaZ2, were calculated, and a statistical evaluation of the data was completed. The results of the study indicate: 1. The zinc oxide-eugenol (ZOE) indexing-investment system produced a narrower range and a significantly smaller mean distortion than the other six indexing-investment systems. 2. The ZOE-stone remount technique showed significantly less distortion than the ZOE-low-fusing metal or the ZOE-acrylic resin techniques. 3. The polyether-stone remount technique demonstrated significantly less distortion than either the polyether-low-fusing metal or the polyether-acrylic resin system. 4. The polyether-stone remount system was not significantly different from the ZOE-low-fusing metal system. 5. The ZOE-stone remount technique demonstrated a smaller range of distortions, but those distortions were not significantly different from those of the polyether-stone remount technique.

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