Angle-of-incidence performance of random anti-reflection structures on curved surfaces.

Random anti-reflection structured surfaces (rARSS) have been reported to improve transmittance of optical-grade fused silica planar substrates to values greater than 99%. These textures are fabricated directly on the substrates using reactive-ion etching techniques, and often result in transmitted spectra with no measurable interference effects (fringes) for a wide range of wavelengths. The inductively coupled reactive-ion plasma (ICP-RIE) used in the fabrication process to etch the rARSS is anisotropic and thus well suited for planar components. The improvement in spectral transmission has been found to be independent of optical incidence angles for values from 0° to ±30°. Qualifying and quantifying the rARSS performance on curved substrates, such as convex lenses, is required to optimize the fabrication of the desired AR effect on optical-power elements. In this work, rARSS was fabricated on fused silica plano-convex lenses using a planar-substrate optimized ICP-RIE process to maximize optical transmission in the range from 500 to 1100 nm. Results are presented from optical transmission tests of rARSS lenses for both TE and TM incident polarizations at a wavelength of 633 nm and over a 70° full field of view. These results suggest optimization of the fabrication process to account for anisotropy is not required, mainly due to the wide angle-of-incidence AR tolerance performance of the rARSS lenses.

Multiphysics modelling, quantum chemistry and risk analysis for corrosion inhibitor design and lifetime prediction.

Organic corrosion inhibitors can provide an effective means to extend the life of equipment in aggressive environments, decrease the environmental, economic, health and safety risks associated with corrosion failures and enable the use of low cost steels in place of corrosion resistant alloys. To guide the construction of advanced models for the design and optimization of the chemical composition of organic inhibitors, and to develop predictive tools for inhibitor performance as a function of alloy and environment, a multiphysics model has been constructed following Staehle's principles of "domains and microprocesses". The multiphysics framework provides a way for science-based modelling of the various phenomena that impact inhibitor efficiency, including chemical thermodynamics and speciation, oil/water partitioning, effect of the inhibitor on multiphase flow, surface adsorption and self-assembled monolayer formation, and the effect of the inhibitor on cathodic and anodic reaction pathways. The fundamental tools required to solve the resulting modelling from a first-principles perspective are also described. Quantification of uncertainty is significant to the development of lifetime prediction models, due to their application for risk management. We therefore also discuss how uncertainty analysis can be coupled with the first-principles approach laid out in this paper.

Tractor overturn concerns in Iowa: perspectives from the Keokuk county rural health study.

Agriculture remains one of the most hazardous industries in the U.S., with tractor overturns producing the greatest number of agricultural machinery-related fatalities. Rollover protective structures (ROPS) and seatbelts effectively reduce tractor overturn deaths. However, a large proportion of tractors in use in American agriculture are older tractors without ROPS and seatbelts. This article describes the tractor-related responses from participants in a population-based study conducted in Keokuk County, Iowa. This study was designed to measure rural and agricultural adverse health and injury outcomes and their respective risk factors. Questionnaires were partially developed from well-documented national surveys. Questions about agricultural machinery use, presence of safety equipment on the machinery, work practices, and attitudes about farm safety were included. Study participants on farms who owned tractors had an average of 3.1 tractors with an average age of 27 years. Only 39% of the 665 tractors had ROPS. Tractor age was associated with the presence of ROPS; 84% of tractors manufactured after 1984 were ROPS-equipped, whereas only 3% of tractors manufactured before 1960 were ROPS-equipped. ROPS-equipped tractors were significantly more common on larger farms and households with higher income. Only 4% of the farmers reported that their tractors had seatbelts and they wore them when operating their tractors. The results of this study support the findings of other studies, which indicate that many older tractors without ROPS and seatbelts remain in use in American agriculture. Until a dramatic reduction in the number of tractors in the U.S. operated without ROPS and seatbelts is achieved, the annual incidence of 120 to 130 deaths associated with tractor overturns will persist.

Unexpected diversity of bacteria capable of carbon monoxide oxidation in a coastal marine environment, and contribution of the Roseobacter-associated clade to total CO oxidation.

The species diversity, phylogenetic affiliations, and physiological activity rates of carbon monoxide-oxidizing microorganisms were investigated, using new isolates from surface waters collected from the coast of New England and type strains from established collections. A direct isolation method allowed the simultaneous recovery of organisms with different growth rates and nutritional requirements and the identification of marine microorganisms that oxidize CO at an environmentally relevant concentration (42 nM CO). Isolates that oxidized CO at environmentally relevant rates (>4.5x10(-11) nmol CO oxidized cell-1 h-1) were taxonomically diverse, with representatives in the alpha and gamma subclasses of the Proteobacteria and the phylum Bacteroidetes, and represent a hitherto unreported metabolic function for several diverse microbial types. Isolates and type strains having the greatest specific rates of CO metabolism (1.1x10(-10) to 2.3x10(-10) nmol CO oxidized cell-1 h-1) belonged to the Roseobacter-associated clade (RAC) of the alpha subclass of the Proteobacteria. By using triple-labeled slide preparations, differential counts of active CO-oxidizing RAC cells, total RAC cells, and total bacterial cell counts in environmental samples were obtained. RAC organisms were a major component of total cell numbers (36%). Based on the density of active CO-oxidizing RAC cells in natural samples and RAC-specific metabolic activities determined for pure cultures, active CO-oxidizing RAC cells may contribute up to 15% of the total CO oxidation occurring in coastal waters.

Isolate-specific synergy in disease symptoms between cauliflower mosaic and turnip vein-clearing viruses.

Simultaneous infection of a plant by two viruses can cause more severe disease than is caused by infection with either virus alone. Such synergy may be due to effects on the replication of one virus by the second virus or to other causes. The tobamovirus turnip vein-clearing virus (TVCV), itself causing almost imperceptible symptoms in infected turnips, exacerbated symptoms of infection of turnip by the Cabbage S isolate of the caulimovirus cauliflower mosaic virus (CaMV). The synergy in symptom production was most evident in a reduced size of leaves, providing an objective measure of synergy. In contrast, synergy did not occur when the CM4-184 isolate of CaMV was used in combination with TVCV. Both isolates of CaMV increased the level of TVCV accumulated in leaves. TVCV did not increase the level of the Cabbage S CaMV isolate. The use of Cabbage S-CM4-184 chimeras revealed that a region critical for isolate synergy in stunting was within the coat protein gene and/or the 5' one third of the reverse transcriptase gene. We conclude that the disease symptom synergy between TVCV and Cabbage S CaMV is not caused by altered levels of accumulation of the viruses, but instead reflects subtle genetic interactions mapping to the ORF IV-ORF V region of CaMV DNA.

Insulin improves well-being for selected elderly type 2 diabetic subjects.

The effects of insulin therapy on patient well-being, treatment satisfaction and mood, and on carer strain were studied in 30 elderly Type 2 diabetic patients (age 73 +/- 7 (SD) yr) in poor glycaemic control on tablet therapy. A comparison group of ten poorly controlled patients who remained on oral agents was also studied. After 4 weeks of insulin treatment, there were significant improvements in mental health, role-emotional, role-physical (all P<0.05) and vitality (P<0.01) domains of the short form health survey (SF-36), and also in the diabetes treatment and satisfaction questionnaire (DTSQ) and geriatric depression scale (both P<0.01) compared to baseline. After 12 weeks, the improvements in mental health, social functioning and vitality (P<0.01 for all domains), and in the DTSQ were sustained. Carer strain was lower at 4 weeks. No changes in outcomes were seen in the comparison group. In selected elderly Type 2 diabetic patients, insulin treatment is associated with significant improvements in well-being, treatment satisfaction and mood, even without significant improvements in glycaemic control and without increase in carer strain. The SF-36 and DTSQ are sensitive to the benefits of the changes in the treatment for these patients.

Characterization of an autotrophic sulfide-oxidizing marine Arcobacter sp. that produces filamentous sulfur.

A coastal marine sulfide-oxidizing autotrophic bacterium produces hydrophilic filamentous sulfur as a novel metabolic end product. Phylogenetic analysis placed the organism in the genus Arcobacter in the epsilon subdivision of the Proteobacteria. This motile vibrioid organism can be considered difficult to grow, preferring to grow under microaerophilic conditions in flowing systems in which a sulfide-oxygen gradient has been established. Purified cell cultures were maintained by using this approach. Essentially all 4',6-diamidino-2-phenylindole dihydrochloride-stained cells in a flowing reactor system hybridized with Arcobacter-specific probes as well as with a probe specific for the sequence obtained from reactor-grown cells. The proposed provisional name for the coastal isolate is "Candidatus Arcobacter sulfidicus." For cells cultured in a flowing reactor system, the sulfide optimum was higher than and the CO(2) fixation activity was as high as or higher than those reported for other sulfur oxidizers, such as Thiomicrospira spp. Cells associated with filamentous sulfur material demonstrated nitrogen fixation capability. No ribulose 1,5-bisphosphate carboxylase/oxygenase could be detected on the basis of radioisotopic activity or by Western blotting techniques, suggesting an alternative pathway of CO(2) fixation. The process of microbial filamentous sulfur formation has been documented in a number of marine environments where both sulfide and oxygen are available. Filamentous sulfur formation by "Candidatus Arcobacter sulfidicus" or similar strains may be an ecologically important process, contributing significantly to primary production in such environments.

Hydrolysis of tert-butyl methyl ether (MTBE) in dilute aqueous acid.

tert-Butyl methyl ether (MTBE) is generally considered to be resistant to chemical transformation in aqueous solution. This lack of reactivity has led to concerns of the long-term impacts of MTBE in groundwater. Although hydrolysis in the presence of strong acids has been recognized as a mechanism for MTBE transformation, it has been discounted as a significant reaction under environmental conditions. In this study, we have examined the fate of MTBE and other ether oxygenates under moderately acidic conditions (> or=pH 1). The results demonstrate that MTBE is sensitive to acid-catalyzed hydrolysis reaction that generates tert-butyl alcohol (TBA) and methanol as products. The reaction is first-order with respect to the concentration of MTBE and hydronium ion with a second-order rate constant of about 0.9 x 10(-2) M(-1) h(-1) at 26 degrees C. Commercially available acidic ion-exchange resins were also shown to catalyze the hydrolysis of MTBE at near neutral pH. Pseudo-first-order rate constants were observed to be as high as 0.03 h(-1) at 25 degrees C and 0.12 h(-1) at 35 degrees C. These findings are discussed in terms of their possible implications for the treatment and environmental fate of MTBE and other gasoline oxygenates.

Responding to the need for faculty development: a survey of U.S. and Canadian dental schools.

The Office of Professional Development at The University of Texas-Houston Health Science Center Dental Branch was established in November 1996 in order to meet the professional development needs of the faculty, staff, and administration. Although other dental schools share similar needs, our research revealed no study to determine how dental schools managed their faculty development needs. Therefore, a preliminary survey to collect data about offices similar to ours was developed and sent to the deans of fifty-four U.S. schools including Puerto Rico and ten Canadian schools. Thirty-seven schools (58 percent) responded, and it was determined that five schools (14 percent) had Offices of Professional Development and seven (19 percent) had Offices of Faculty Affairs. Based on these results, an expanded follow-up survey was conducted. The respondents were asked to indicate 1) which entity within the school was primarily responsible for handling faculty development, and 2) which entity actually sponsored each of eighteen faculty development activities. With a response from thirty-three U.S. schools (61 percent) and six Canadian schools (60 percent), six administrative structures (models) for faculty development were identified: 1) Office of Academic Affairs, 2) Departmental Chair, 3) a Faculty Development Committee, 4) an Office of the Dean, 5) an Office of Faculty/Professional Development, and 6) Other Resources.

A simple automated continuous-flow-equilibration method for measuring carbon monoxide in seawater.

A simple, robust, low-maintenance method using air-segmented continuous-flow equilibration was developed and automated to measure carbon monoxide (CO) in natural waters precisely and accurately. Finely regulated flows of CO-free air and of seawater or standard water were pumped into a glass coil, forming discrete gas/liquid segments. The partially CO-equilibrated gas effluent was injected into a Trace Analytical reduction analyzer for CO detection. A semiempirical mass-balance model was established for predicting and optimizing the performance of the CO extractor. The optimized gas and water flow rates were approximately 1.2 and approximately 14 mL min(-1), respectively, giving a response time of less than 15 min and a CO-extraction yield of approximately 80%. The analytical blank, precision, and accuracy were, respectively, 0.02 nM, +/-2.5% (at the approximately 1 nM level), and better than 5%. Two extractors can be interfaced to one detector at 4-6 samples per hour for each extractor. Coupled with a continuous surface-water sampler, the system was successfully applied to monitoring the diurnal variation of CO concentration in Sargasso Sea surface waters.

Comparison of a direct-reading device to gravimetric methods for evaluating organic dust aerosols in an enclosed swine production environment.

The production of livestock in enclosed facilities has become an accepted practice, driven by the need for increased efficiency. Exposure to organic dusts, containing various bioactive components, has been identified an important risk factor for the high rate of lung disease found among workers in these environments. Assessment of organic dust exposure requires technical skills and instrumentation not readily available to most agricultural enterprises. Development of a simple, cost-effective method for measuring organic dust levels would be useful in evaluating and controlling exposures in these environments. The objective of this study was to evaluate the usefulness of the direct reading MIE PDM-3 Miniram for estimating organic dust concentrations in enclosed swine production facilities. Responses from the MIE PDM-3 Miniram were compared to gravimetric methods for total and inhalable dust. Total dust determinations were conducted in accordance with the National Institute for Occupational Safety and Health (NIOSH) method 0500. Inhalable particulate mass (IPM) sampling was conducted using SKC brand IOM (Institute of Occupational Medicine) sampling cassettes, which meet the American Conference of Governmental Industrial Hygienists ACGIH criteria for inhalable dust sampling. This study design also allowed for the comparison of traditional total dust method to the IPM method, in collecting organic dusts in an agricultural setting. Fifteen sets of side-by-side samples (Miniram, total dust, and IPM) were collected over a period of six months in a swine confinement building. There were statistically significant differences in the results provided by the three sampling methods. Measurements for inhalable dust exceeded those for total dust in eleven of fifteen samples. The Miniram time-weighted average (TWA) response to the organic dust was always the lower of the three methods. A high degree of correlation was found among all three methods. The Miniram performed well under field conditions of varying temperature and humidity. The Miniram has the potential to predict the inhalable and total dust concentrations, assuming a correction factor for the organic dust being measured is applied.

The prevalence of diabetes mellitus and quality of diabetic care in residential and nursing homes. A postal survey.

OBJECTIVE: to investigate the prevalence of known diabetes mellitus in care homes and the patterns of diabetes care in these institutions. DESIGN: a postal questionnaire sent to all 98 care homes in Sheffield. RESULTS: 70 care homes (71%) returned the questionnaire, indicating that 233 (8.8%) of 2648 residents were known to have diabetes. Of these, 76 (33%) were treated with diet alone, 105 (45%) with diet plus oral medication and 52 (22%) with insulin. Only seven registered nurses (2%) in the homes had certified diabetes training. Forty-two homes (60%) did not carry out a structured, diabetes-related assessment of residents on entry and only 29 (42%) had regular review of diabetic residents by a general practitioner or practice nurse. Most homes (89%) were visited by an optician, 56 (80%) also had a regular chiropody service, although 32 (46%) of these charged their residents for this service. CONCLUSIONS: the known prevalence of diabetes is similar to that reported previously. This study highlights the need for structured care with defined standards for care-home residents with diabetes.

Breast reconstruction in ectodermal dysplasia.

Patients with ectodermal dysplasia may request breast reconstruction. In addition to abnormalities of other ectodermally derived structures, the breast and nipple-areolar complex may be absent or hypoplastic. Although this group of patients may have concerns with hair, nails, teeth, or even upper limb malformations, this report focuses on reconstruction of the breast anomalies. Four unrelated patients with ectodermal dysplasia who have undergone breast reconstruction are discussed.

Acute development of invasive squamous cell carcinoma in a split-thickness skin graft donor site.

Reports exist in the literature where metastasis or inadvertent operative spread has transferred excised squamous cell carcinoma, keratoacanthoma, and melanoma to skin graft donor sites. This report examines the potential for the reverse to occur. A de novo squamous cell carcinoma developing in a split-thickness skin graft donor site within 5 weeks of harvest for acute burn coverage is presented. As repeated harvesting from this site was performed, the transplantation of carcinoma could have occurred. The etiology of this squamous cell carcinoma, the risk of transplantation, and the 18-month follow-up are presented.

Performance of the Coumatrak system in a large anticoagulation clinic.

There is a need to monitor anticoagulation accurately, inexpensively, and rapidly. The accuracy and precision of a simple fingerstick method was studied in a large outpatient anticoagulation clinic using the Coumatrak method. The Coumatrak apparatus has been studied in the home setting, and three recent reports suggest that it is practical, accurate, and possibly superior to the standard method. These results differ from recently published studies. This technique was found to be less than acceptable in precision and accuracy. This method requires further study before it can be recommended for wide-spread use in making decisions for patient care.

Importance of continued testicular suppression in hormone-refractory prostate cancer.

PURPOSE: Patients in whom prostate cancer progresses despite testicular androgen ablation are generally said to have cancers that have become resistant to hormonal maneuvers. If androgen suppression has been pharmacologic, this therapy is often stopped before consideration of other systemic treatments. This exploratory study sought clinical correlates of experimental evidence that there may be substantial acceleration of tumor growth after cessation of androgen suppression. MATERIALS AND METHODS: A retrospective multivariate analysis was performed on survival data for 341 patients treated on four clinical trials of secondary therapy for hormone-refractory prostate cancer. Factors included in the model were recent weight loss, age, performance status, disease site (soft tissue v bone-dominant), prior radiotherapy, and continued androgen suppression v discontinued exogenous endocrine therapy. RESULTS: Recent weight loss, age, performance status, and disease site were important prognostic factors for survival duration in hormone-refractory prostate cancer. Correcting for these factors, continued testicular androgen suppression was also an important predictor of survival duration in all data sets examined. CONCLUSION: This retrospective study showed a modest advantage in survival duration for men with hormone-refractory prostate cancer who continued to receive testicular androgen suppression. The hypothesis that continued hormonal maneuvers can still affect survival in this group warrants examination in prospective trials.

Efficacy of a home-based human immunodeficiency virus prevention video program for teens and parents.

Family-based communication about sexual behavior and sexuality is a predominate theme in the key risk reduction and service objectives for human immunodeficiency virus (HIV) prevention and related issues in Healthy People 2000. These recommendations are particularly poignant for younger adolescents who are not yet sexually active and whose social orientation is primarily to family and parents. A family-centered, home-based, video program to foster parent and teen knowledge and communication regarding issues related to HIV prevention and to increase family and teen communication skills was used in an intensive field test of program efficacy. Sixty-nine families with at least one adolescent age 12 to 14 years were recruited through their primary-care physicians and were randomly assigned to either experimental (video with information and skills training) or control (video with information only) conditions in a pre-posttest with a 4-month follow-up design. Both versions of the video program resulted in substantial increases in HIV-related knowledge for parents and teens, but only the skill-training (experimental) version produced increases in knowledge of communication skills and behavioral demonstrations of family problem solving. Approaches for a broader and more effective parent-training video program and for dissemination through primary-care physicians are discussed.

Family/media approach to HIV prevention: results with a home-based, parent-teen video program.

We describe the first study with a home-based HIV prevention video program for parents and young teenagers. The objectives of the program are to inform parents and teenagers about the causes and prevention of HIV infection and other sexually transmitted diseases, to increase family problem-solving skills, and to increase teen problem-solving and assertiveness skills. The objectives pertain to the goals of increasing skills needed to help teenagers avoid or manage high-risk behaviors and situations. Forty-five families with at least one 12- to 14-year-old were randomly assigned to either experimental (receive video program) or control (no video) conditions in a pretest-posttest design. After 6 months (Follow-Up 1), the experimental and control families were reassessed. The control families next received the video program, and the control families were assessed again (Follow-Up 2). The results indicate increases in parent and teen knowledge and skills only with video viewing. Approaches to improving the video program, particularly with teenagers, are discussed.

Nuclear binding of the estrogen receptor: a potential predictor for hormone response in metastatic breast cancer.

We have previously described an in vitro immunohistochemical test employing anti-receptor antibodies, for demonstrating the nuclear binding characteristics of estrogen receptors (ER) in breast carcinomas. Based on a retrospective analysis of twenty-five patients with estrogen receptor-positive (ER+) breast cancer who were treated with hormone therapy and whose clinical responses were evaluable, we were able to demonstrate that this test may be valuable to predict which, among the ER+ tumors (whether or not they are progesterone receptor positive, PR+), are likely to respond to hormone therapy and which may fail. While tumors in which ER exhibited abnormalities in nuclear binding behavior (ligand-independent nuclear binding or no nuclear binding) failed hormone therapy (16 out of 19 patients), those in which nuclear binding of ER appeared normal (ligand-dependent) in the in vitro test, responded to hormone therapy (5/6 patients). While our previous report dealt with the procedural details, specificity of the reagents, and the design of the study, this report addresses the clinical aspects of this study and response correlation.