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Recent epidemics of Fusarium head blight (FHB) severely damaged the hard red spring wheat and barley crops in Minnesota. Samples of commercial grain were analyzed in 1993 and 1994 to determine the effects of FHB on several quality parameters. Wheat test weight (TW) averaged 832 kg m-3 (55.4 lb/bu), thousand kernel weight (TKW) averaged 27.4 g, and the proportion of visually scabby kernels (VSK) averaged 11.0%. Deoxynivalenol (DON) was detected in 493 of 500 samples (98.6%). The mean concentration was 8.3 μg/g (range = 0.0 to 44.7 μg/g). Scab in wheat could rapidly be estimated using easy-to-prepare visual comparison standards. Scores of percent VSK were correlated with DON concentration at r = 0.897 and 0.908 in 1993 and 1994, respectively. TW and TKW were less effective estimators of DON (r = -0.622 and -0.550, respectively). DON was detected in 100 of 100 six-row barley samples collected during the survey and averaged 10.4 μg/g (range = 0.5 to 39.7 μg/g). DON concentration in barley could not be effectively estimated with grading parameters including TW, TKW, percent plump kernels, or a visual index of kernel discoloration. In 28 samples of oats, DON averaged 1.4 μg/g (range = 0.0 to 6.4 μg/g). Nivalenol was not detected in any of the 628 samples analyzed during the two-year study.

Multijunction III-V concentrator cells of several different types have demonstrated solar conversion efficiency over 40% since 2006, and represent the only third-generation photovoltaic technology to enter commercial power generation markets so far. The next stage of solar cell efficiency improvement, from 40% to 50%-efficient production cells, is perhaps the most important yet, since it is in this range that concentrator photovoltaic (CPV) systems can become the lowest cost option for solar electricity, competing with conventional power generation without government subsidies. The impact of 40% and 50% cell efficiency on cost-effective geographic regions for CPV systems is calculated in the continental US, Europe, and North Africa. We take a systematic look at a progression of multijunction cell architectures that will take us up to 50% efficiency, using modeling grounded in well-characterized solar cell materials systems of today's 40% cells, discussing the theoretical, materials science, and manufacturing considerations for the most promising approaches. The effects of varying solar spectrum and current balance on energy production in 4-junction, 5-junction, and 6-junction terrestrial concentrator cells are shown to be noticeable, but are far outweighed by the increased efficiency of these advanced cell designs. Production efficiency distributions of the last five generations of terrestrial concentrator solar cells are discussed. Experimental results are shown for a highly manufacturable, upright metamorphic 3-junction GaInP/GaInAs/Ge solar cell with 41.6% efficiency independently confirmed at 484 suns (48.4 W/cm2) (AM1.5D, ASTM G173-03, 25 °C), the highest demonstrated for a cell of this type requiring a single metal-organic vapor-phase epitaxy growth run. Copyright © 2012 John Wiley & Sons, Ltd.

Multijunction solar cells based on III-V semiconductors, having recently demonstrated 43.5%, remain the world's most efficient solar cells, and the preferred technology in point-focus and dense-array concentrator photovoltaic (CPV) system architectures. The year 2011 proved to be a pivotal year for CPV technology, with multiple power plant installations in the megawatt to tens of megawatt scale. Spectrolab is working closely with CPV system manufacturers to provide a reliable and well-characterized cell technology, in volumes commensurate with this increasing demand. The evolutionary C3MJ+ and the C4MJ cell technologies are the latest in a sequence of CPV solar cell designs, with conversion efficiencies approaching or greater than 40%. Both technologies have completed detailed characterization and qualification programs, including accelerated laboratory and (for C4MJ) on-sun reliability testing, and have entered into high volume production at Spectrolab's manufacturing facility in Sylmar, CA. The metamorphic C4MJ technology affords new opportunities to optimize cell designs, taking into consideration both the spectral optical transmittance of a particular CPV system and the installation site's average solar resource over a typical meteorological year.

The control of environmental noise is becoming of increasing importance to the European Commission. As a result, they have recently instigated a set of legislative initiatives in order to prevent increases in noise exposure for the population and, where possible, to reduce that exposure. This paper introduces current European Union environmental noise policy, as implemented through the Environmental Noise Directive of 2002, and describes the work of the related research projects “HARMONOISE” and “IMAGINE.” The paper then focuses on railway-specific issues, with detail of the railway noise prediction methodology developed within these projects, including the source database that is now in place. In parallel, the Commission has introduced, within railway Technical Specifications for Interoperability, noise emission limits for new and refurbished trains, as a means of progressively reducing railway noise at source. The noise elements of these Specifications are described and discussed.

This paper investigates a significant reduction in environmental noise attributable to changes in the Network Rail grinding strategy employed within Great Britain (GB). Acoustic Track Quality (ATQ) is a measure of the surface roughness of the running rails. Rail roughness has a major influence on wayside rolling noise levels during the passage of a train. Levels of ATQ have been determined for approximately 1,100 km of track on GB’s East and West Coast mainlines from wayside noise measurements and data collected by an under-floor microphone system fitted to a train. The results show a substantial apparent reduction in rail surface roughness and associated wayside noise levels since a similar study was undertaken in 2004, and demonstrate how a maintenance rail grinding strategy can potentially reduce wayside noise levels across large parts of a railway network.

When measuring the noise and vibration from trains it is necessary first to establish how much data needs to be collected in order to achieve the required level of accuracy. Existing measurement standards tend to concentrate on controlling the train speed, the condition of the track and the condition of the train, but do not indicate how much data is required. This paper sets out to establish how much data is necessary for a particular type of measurement situation. Using the measured distributions of noise and vibration data, the Monte Carlo method is used to determine the amount the sample mean may vary from the population mean as a function of the number of samples. This information can then be used to determine the number of trains that would need to be measured to achieve a particular level of accuracy. It has been found that if noise measurements are taken for trains comprising identical vehicles then, if the sample mean is to be within approximately ±1 dB of the true value, then measurements would need to be made on at least 34 vehicles. When the trains contain different types of vehicle, the number of measurements increases. With ground-borne vibration it was found that at least 40 trains, each comprising nine coaches and a locomotive, were required to be able to measure the vibration dose value with a degree of accuracy that is equivalent to ±1 dB.

An assessment of women's knowledge of cervical screening and cervical cancer was considered important as up to 92% of those dying from this form of cancer had never been tested. What were the reasons which determined their non-attendance? Issues to be addressed were reactions to invitation, women's knowledge of screening, and the possible factors which they envisaged as being associated with cervical cancer. Other issues to be considered were practical problems associated with attendance, and preference for the sex and professional status of the health professionals involved; 187 women in a general practitioner practice in Lothian, Scotland were targeted by questionnaire. As with other studies in this field 50% of those contacted were ineligible for a variety of reasons. Seventy-two women completed the questionnaire, providing a mix of qualitative and quantitative data. Although the majority of women felt the invitation to attend screening was clear and easy to understand, there was a lack of knowledge with regard to both the screening itself and the possible causes of cervical cancer. The main 'causes' were seen as higher sexual activity among those aged under 37 and smoking and a virus by those over 37. The majority of women showed preference for a female professional to take the smear. Practical problems of time and venue were not considered insurmountable. The main reasons cited for non-compliance were the fear and dislike of the test itself.

SummaryThe manure that is returned to croplands each year is an important resource in the subsistence farming systems of eastern Kenya. Measurements on several farms have shown that the manure being used is of very poor quality. Analyses of soil samples from beneath the bomas (small enclosures) where animals are kept indicate that substantial losses of nutrients occur through leaching; ammonia volatilization and denitrification may also be involved. Current practice is to apply the manure at rates that appear to make poor use of this scarce resource. The findings are discussed in terms of what changes to the system may be feasible to reduce losses of nutrients, and to improve the quality of the manure and the effectiveness of its use.

This paper presents an environment for publishing information on the World-Wide Web (WWW). Previous work has pointed out that the explosive growth of the WWW is in part due to the ease with which information can be made available to Web users [23]. Yet this property can have negative impacts on the ability to find appropriate information as well as on the integrity of the information published. We present a prototype environment that facilitates the publishing of documents on the Web by automatically generating meta-information about the document, communicating this to a local scalable architecture, e.g. WHOIS + +, verifying the document's HTML compliance, maintaining referential integrity within the local database, and placing the document in a Web accessible area. Additionally, maintenance and versioning facilities are provided. This paper first discusses an idealized publishing environment, then describes our implementation, followed by a discussion of salient issues and future research areas.

Multijunction solar cells used in concentrating photovoltaic (CPV) systems deliver solar power at low cost in high DNI climates where the solar resource is greatest. Because the cells subdivide the solar spectrum and are used with optical systems of varying spectral response, careful evaluation and optimization of cell performance under real field conditions is important. This paper presents modeled performance of the latest generation Spectrolab cells in systems with PMMA and silicone-on-glass optics, using a simple cell temperature model, TMY3 data, and the SMARTS spectral irradiance model. Results show that the improved efficiency of C4P5 cells compared to the lattice-matched C3P5 cells is more pronounced in systems with PMMA optics.

SUMMARYThe effects of temperature and soil water potential on maize germination were investigated in controlled environment conditions and the effects of depth of planting and a mulch on maize emergence were studied in a field experiment in eastern Kenya. The rate of germination increased to an optimum temperature of 33.6°C above a base temperature of 6.1°C and decreased above the optimum to zero germination at 42.9°C. The thermal time for median germination increased from 51.5°Cd to 56.4°Cd as soil matric potential decreased from -5 to -40 kPa. Soil water content, depth of planting, and their interaction had significant (P < 0.001) effects on final germination and emergence but mulch, or any interactions involving mulch, had no such effects. Increasing depth of planting by 1 cm increased the thermal time required for emergence by 2.8°Cd, and decreasing water content by 1% increased the thermal time required for emergence by 3.2°Cd.Germinación y emergencia del maíz

Spectrolab is qualifying its fourth generation of terrestrial concentrator multijunction cells (C4MJ). Prototypes of this product have been tested with an average efficiency of 40% at 50 W/cm2 illumination. This new generation is a departure from previous production technology in that, for the first time, it employs metamorphic rather than lattice-matched technology.

Multijunction solar cells based on III–V semiconductors are the most efficient solar cells in the world, and of the established photovoltaic technologies, have the greatest potential for future growth in efficiency. Champion cells with efficiency greater than 40% have been demonstrated by several groups since 2006, and in that same period, the efficiency of cells in mass production has also increased steadily. These devices offer the promise of very competitive solar power systems exploiting the high efficiency under high optical concentration. To this end, Spectrolab is conducting a multi-year program to develop solar cells with still higher efficiency and substantial cost reductions and to fully characterize and qualify them for reliable performance in the field. Development of the fourth production generation with 40% average production efficiency is nearing completion. Cell design and performance will be presented, with a summary of qualification and field test status. Progress in ongoing efforts to automate cell production for cost reduction and increased manufacturing capacity will be discussed. Development of these high-performance multijunction CPV cells is key to the emergence of CPV technology as the lowest cost solar power solution in high DNI areas.

The Boeing Company Phantom Works has developed three different prototype photovoltaic concentrator arrays since March 2007. Identified as Prototype A, B and C, the experimentally proven technical characteristics of each design are presented. The concentrator designs utilize a 1 cm2 multi-junction solar cell assembly in conjunction with SMS non-imaging optical designs [1, 2] manufactured with low-cost mass-producible technologies. Prototype A is an on-axis XR optical concentrator with a 733x geometrical concentration demonstrating a ± 1.73° acceptance angle and 23.7% conversion efficiency. Prototype B is an off-axis free-form XR optical concentrator with a 810x geometrical concentration demonstrating a ± 1.32° acceptance angle and 25.3% conversion efficiency. Prototype C is the most recent off-axis free-form XR optical concentrator with a 801x geometrical concentration and a theoretical ±1.80° acceptance angle demonstrating a conversion efficiency greater than 27.0%. Prototype C is also the basis for the Boeing Proof of Design (POD) module, demonstrating an acceptance angle of ±1.48° and a conversion efficiency of 29.4% (as of May 8, 2009). Manufacturability has been paramount during the design process, resulting in high performance concentrating photovoltaic modules using production quality components.

Multijunction solar cells based on III-V semiconductors are the most efficient solar cells in the world, with record efficiencies of over 40%. These devices offer the promise of very competitive solar power systems exploiting the high efficiency devices under high optical concentration. To make this promise a reality, Spectrolab is conducting a multi-year program to develop solar cells with still higher efficiency and substantial cost reductions and to fully characterize and qualify them for reliable performance in the field. Qualification of a second generation cell technology has recently been completed. Cell performance, qualification, and field test data will be presented; progress on performance improvements, cost reductions, and manufacturing capacity plans will be discussed. Development of these high-performance multijunction CPV cells promises to break the bottleneck currently limiting growth in photovoltaic power generation.

A novel photovoltaic concentrator is presented. The goal is to achieve high concentration design with high efficiency and high acceptance angle that in the same time is compact and convenient for thermal and mechanical management [1]. This photovoltaic system is based on 1 cm 2 multi-junction tandem solar cells and an XR concentrator. The XR concentrator in this system is an SMS 3D design formed by one reflective (X) and one refractive (R) free-form surfaces (i.e., without rotational or linear symmetry) and has been chosen for its excellent aspect ratio and for its ability to perform near the thermodynamic limit. It is a mirror-lens device that has no shadowing elements and has square entry aperture (the whole system aperture area is used for collecting light). This large acceptance angle relaxes the manufacturing tolerances of all the optical and mechanical components of the system included the concentrator itself and is one of the keys to get a cost competitive photovoltaic generator. For the geometrical concentration of 1000x the simulation results show the acceptance angle of ±1.8 deg. The irradiance distribution on the cell is achieved with ultra-short homogenizing prism, whose size is optimised to keep the maximum values under the ones that the cell can accept. The application of the XR optics to high-concentration is being developed in a consortium leaded by The Boeing Company, which has been awarded a project by US DOE in the framework of the Solar America Initiative.

European Commission Directive 2002/49/EC requires that Common Assessment methods for the modelling of noise from road, rail, aviation and industry shall be established by the Commission. The research project HARMONOISE was funded under the European 5 th Framework programme in order to commence this process. The research has been continued through the 6 th Framework project IMAGINE to a point where the delivered suite of procedures, algorithms and databases may be implemented as required by the Commission. This paper describes the overall IMAGINE approach in general terms. It then focuses on the development of a practical methodology for the rail-specific elements of the model. These comprise a source term database of examples and default information for individual rail vehicles, and a process for combining this data into traffic source lines that interface with the IMAGINE propagation model.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 843-848, A novel photovoltaic concentrator is presented. The goal is to achieve high concentration design with high efficiency and high acceptance angle that in the same time is compact and convenient for thermal and mechanical management [1]. This photovoltaic system is based on 1 cm2 multi-junction tandem solar cells and an XR concentrator. The XR concentrator in this system is an SMS 3D design formed by one reflective (X) and one refractive (R) free-form surfaces (i.e., without rotational or linear symmetry) and has been chosen for its excellent aspect ratio and for its ability to perform near the thermodynamic limit. It is a mirror-lens device that has no shadowing elements and has square entry aperture (the whole system aperture area is used for collecting light). This large acceptance angle relaxes the manufacturing tolerances of all the optical and mechanical components of the system included the concentrator itself and is one of the keys to get a cost competitive photovoltaic generator. For the geometrical concentration of 1000x the simulation results show the acceptance angle of ±1.8 deg. The irradiance distribution on the cell is achieved with ultra-short homogenizing prism, whose size is optimised to keep the maximum values under the ones that the cell can accept. The application of the XR optics to high-concentration is being developed in a consortium leaded by The Boeing Company, which has been awarded a project by US DOE in the framework of the Solar America Initiative.

The performance of the XR solar concentrator, using a high efficiency multi-junction solar cell developed recently by Spectrolab, is presented. The XR concentrator is an ultra-compact Nonimaging optical design composed of a primary mirror and a secondary lens, which can perform close to the thermodynamic limit of concentration (maximum acceptance angle for a given geometrical concentration). The expected acceptance angle of the concentrator is about ±2 deg for a geometrical concentration of 800x (a Fresnel lens and secondary system typically has ±0.6 deg of acceptance for 300x of geometrical concentration). This concentrator is optimized to improve the irradiance distribution on the solar cell keeping it under the maximum values the cell can accept. The XR concentrator has high manufacturing tolerance to errors and can be produced using low cost manufacturing techniques. The XR is designed with the Simultaneous Multiple Surface (SMS) design method of Nonimaging Optics. Its application to high-concentration photovoltaics is now being developed in a consortium led by The Boeing Company, which has recently been awarded a project by the US DOE in the framework of the Solar America Initiative.

The performance of the XR solar concentrator, using a high efficiency multi-junction solar cell developed recently by Spectrolab, is presented. The XR concentrator is an ultra-compact Nonimaging optical design composed of a primary mirror and a secondary lens, which can perform close to the thermodynamic limit of concentration (maximum acceptance angle for a given geometrical concentration). The expected acceptance angle of the concentrator is about ±2 deg for a geometrical concentration of 800x (a Fresnel lens and secondary system typically has ±0.6 deg of acceptance for 300x of geometrical concentration). This concentrator is optimized to improve the irradiance distribution on the solar cell keeping it under the maximum values the cell can accept. The XR concentrator has high manufacturing tolerance to errors and can be produced using low cost manufacturing techniques. The XR is designed with the Simultaneous Multiple Surface (SMS) design method of Nonimaging Optics. Its application to high-concentration photovoltaics is now being developed in a consortium led by The Boeing Company, which has recently been awarded a project by the US DOE in the framework of the Solar America Initiative.

Recurrent events in clinical trials have typically been analysed using either a multiple time-to-event method or a direct approach based on the distribution of the number of events. An area of application for these methods is exacerbation data from respiratory clinical trials. The different approaches to the analysis and the issues involved are illustrated for a large trial (n = 1465) in chronic obstructive pulmonary disease (COPD). For exacerbation rates, clinical interest centres on a direct comparison of rates for each treatment which favours the distribution-based analysis, rather than a time-to-event approach. Poisson regression has often been employed and has recently been recommended as the appropriate method of analysis for COPD exacerbations but the key assumptions often appear unreasonable for this analysis. By contrast use of a negative binomial model which corresponds to assuming a separate Poisson parameter for each subject offers a more appealing approach. Non-parametric methods avoid some of the assumptions required by these models, but do not provide appropriate estimates of treatment effects because of the discrete and bounded nature of the data.

The in vivo function of the unusual population of CD56+ CD16- endometrial granulated lymphocytes (eGLs) in human endometrium is unknown; their increased numbers in the secretory phase of the menstrual cycle suggests that they may play a role in the immunobiology of nonpregnant endometrium. In the present study, the phenotype and proliferative responses of eGLs at various phases of the menstrual cycle were compared with those in early pregnancy. Endometrial GLs were highly purified (98% CD56+) using immunomagnetic separation, and the expression of cell surface antigens was examined in smears using a double immunohistochemical labeling technique. Proliferative responses to mitogens and interleukin 2 (IL-2) were assessed in hanging drops in 60-well Terasaki plates. There was low to no expression of CD3, CD8, CD16, HML-1, L-selectin, and CD25 (IL-2 receptor alpha) on CD56+ cells isolated from nonpregnant and pregnant endometrium. The expression of CD2, CD49a, and CD122 (IL-2 receptor beta, IL-2Rbeta), however, increased from the proliferative to the late secretory phase of the menstrual cycle. In contrast, CD11a, CD69, and CD49d expression was high and did not vary with menstrual cycle phase; CD49d levels were significantly reduced in early pregnancy. Unlike early-pregnancy eGLs, none of the CD56+ eGL cultures throughout the menstrual cycle displayed phytohaemagglutinin (PHA)-induced lymphoproliferation. In contrast, eGLs from nonpregnant endometrium in the presence of 5 or 100 U/ml IL-2 after 48- and 120-h incubation showed significant proliferative responses, as did eGL cultures from early pregnancy. A significantly reduced number of proliferative phase eGL cultures proliferated in response to IL-2 compared to secretory phase and early-pregnancy eGL cultures. The IL-2-induced proliferative responses of CD56+ eGLs were associated with increased IL-2Rbeta (CD122) expression. These findings demonstrate 1) differential eGL expression of CD2, CD49a, and CD122 during the menstrual cycle; 2) differential IL-2-induced eGL proliferative responses during the menstrual cycle; and 3) differences between eGLs from nonpregnant and pregnant endometrium in CD49d expression and their ability to respond to PHA.

Human endometrial leukocytes undergo regular cyclical changes during the menstrual cycle, with a striking increase in the phenotypically unusual population of CD56+ CD16- endometrial granulated lymphocytes (eGLs) in the late secretory phase and early pregnancy. The factors that regulate this increase in eGL numbers are unclear; their unusual morphology, however, has led to the suggestion that they undergo apoptosis at the end of the menstrual cycle. Apoptosis, bcl-2 expression, and proliferative activity were examined in the stroma of normal cycling, progesterone-treated, and early-pregnancy endometrium. The expression of bcl-2 and the Ki67 proliferation marker by highly purified (98% CD56+) eGLs from endometrium during the menstrual cycle and from first-trimester decidua was also studied. Apoptotic cells were rarely observed in the endometrial stroma of any of the samples examined. Stromal bcl-2 expression, however, increased from the proliferative to the premenstrual phase, and double immunohistochemical labeling demonstrated large numbers of bcl-2+ CD56+ eGLs. In contrast, Ki67 expression was high in the endometrial stroma during the proliferative phase, fell during the secretory phase, and rose again premenstrually, because of expression by eGLs. Isolated CD56+ eGLs also showed high bcl-2 and Ki67 expression at the end of the menstrual cycle. Unlike premenstrual endometrium, progesterone-treated endometrium and first-trimester decidua contained few proliferating cells, expressed high levels of bcl-2, and showed no evidence of apoptosis. Thus, eGLs do not undergo apoptosis in premenstrual endometrium, and their regulatory mechanisms remain to be clarified.

CD56+ CD16- granulated lymphocytes, termed endometrial granulated lymphocytes (eGLs), have been suggested to play a role in the maintenance of human pregnancy, although their in vivo function in both pregnant and nonpregnant endometrium remains unknown. The present study compared the cytotoxic activity of CD56+ CD16- eGLs (98% purity) positively selected from early and late proliferative-phase, early and late secretory-phase, and menstrual-phase endometrium with that of CD56+ CD16- eGLs purified from first-trimester decidua and CD56+ predominantly CD16+ cells from peripheral blood. From the late proliferative phase onwards, the major histocompatibility complex (MHC)-nonrestricted cytotoxic activity of eGLs was comparable between phases of the menstrual cycle. In contrast, eGLs from early proliferative-phase endometrium displayed significantly lower cytotoxic activity. With the exception of eGLs purified from early proliferative-phase endometrium, the cytotoxic activity of CD56+ CD16- eGLs purified from nonpregnant endometrium was comparable to that of CD56+ CD16- eGLs in decidua and CD56+ predominantly CD16+ cells from peripheral blood. No endogenous lymphokine-activated killer cell activity was detected in eGLs from endometrium or decidua. The present study using highly purified eGLs demonstrates that, with the exception of early proliferative-phase samples, CD56+ CD16- eGLs from nonpregnant endometrium and early pregnancy decidua have cytotoxic activity comparable to that of "classical" natural killer cells from peripheral blood.

Organizations involved in natural resource management are increasingly being affected by the state of their knowledge about ecological conditions characterizing their land base and how these conditions influence land use, resource planning, and business decisions. This need for a greater understanding of the ecological nature of the forest is being driven by a number of environmental, economic, and socio-political factors. Forest management is now really forestland management, in the broadest sense of the word “land”. With this changing outlook, we are seeing an emergence of more ecological management approaches which are better able to accomodate non-timber values, anticipate and mitigate environmental impacts of forest operations, and which are beginning to address the principles of sustainable development and integrated resource management.

As the field of sleep disorders medicine continues to mature, appropriate diagnostic techniques are becoming properly defined and standardized. This article focuses principally upon diagnostic testing for sleep apnea, although other sleep disorders are discussed briefly. When interpreting a polysomnogram, one must consider a number of complex variables. A critical discussion of the methods for adequately measuring these variables is provided together with guidelines for appropriate interpretation.

OBJECTIVE : To assess the efficacy of an over-the-counter mechanical nasal dilator during sleep in pregnant women with nasal congestion. STUDY DESIGN : Pregnant women with symptoms of nocturnal nasal congestion not attributed to allergies or cold symptoms were randomized in a double-blind manner to receive either a spring-loaded device or placebo device without a spring. Each patient assessed breathing and sleep quality for a three-day baseline and three-day treatment period. A 10-question diary was utilized to assess breathing, ease of falling asleep, sleep quality, and continuity and depth of sleep. Averaged scores for each question were computed for baseline and treatment periods, and differences were calculated. Statistical analyses were by the sign test, Fisher's exact test and Student's t test. RESULTS : Thirty-four (21%) of 160 screened patients were enrolled into the study ; 24 (15%) completed the study. All agreed to being assigned to receive either the spring-loaded device (n = 12) or a placebo (n = 12) device. Responses to 8 of the 10 questions favored the former as compared with the placebo (P =.05, sign test). Moreover, patients treated with the spring-loaded device gave more favorable responses to the question, Overall, compared with most nights, how easy was your breathing throughout last night ? (P=.02, t test). CONCLUSION : Use of this drug-free external nasal dilator improved the ease of breathing among patients with pregnancy-related nocturnal congestion.

Twelve shrub rose cultivars were evaluated for pest resistance in the southern Blue Ridge mountains under high humidity and rainfall (1.34 inches per week average during the 1994 and 1995 growing seasons). `Albo plena', `Blanc Double de Coubert', `Fru Dagmar Hastrup', `Roseraie de l'Hay', R. rugosa `Alba', `Sarah van Fleet', and `Topaz Jewel' were highly resistant to black spot and Cercospora sp. leaf spot. `Alba Meidiland', `Linda Campbell', `Pink Meidiland', and `Scarlet Meidiland' were susceptible, while `Bonica' displayed intermediate resistance to both diseases. `Sarah van Fleet' foliage and the flowers of `Albo plena', `Blanc Double de Coubert', and R. rugosa `Alba' were damaged by Japanese beetle feeding. No other cultivars were damaged by Japanese beetles.

Gas chromatography and integrated computer software (Microbial Identification System, Microbial ID, Inc., Newark, DE) were used to identify and compare fatty acid compositions among isolates representing three intraspecific groups of Rhizoctonia solani anastomosis group 1 (AG-1). The major fatty acids found, constituting 94-96% of the C9-C20 fatty acids present, were linoleic (18:2 cis 9, 12), oleic (18:1 cis 9), and palmitic (16:0). Smaller amounts of nine other fatty acids were consistently identified in preparations from 2- and 4-day-old cultures. Library entries were generated for the intraspecific groups AG-1 IA, AG-1 IB, and AG-1 IC [...]

A population of Rhizoctonia solani representing AG-2-2 IIIB (mat rush type) and AG-2-2 populations isolated from corn, sugar beet, and turfgrass were analyzed for cellular fatty acid composition. The AG-2-2 IIIB population and populations of isolates from turfgrass and from sugar beet (AG-2-2 IV) were differentiated by cluster and principal component analyses of the percent composition of the fatty acids identified. A dendrogram of the four populations shows that AG-2-2 IIIB and the population from corn were closely related, and the population from turf was distinct from AG-2-2 IIIB and AG-2-2 IV

Historically, Rhizoctonia solani anastomosis group 3 (AG-3) was regarded as host specific, composed of isolates causing black scurf of potato. Recently, isolates of R. solani AG-3 were reported causing target spot of tobacco in South Africa. In the United States, isolates causing target spot of tobacco were identified as AG-2-2. Our anastomosis tests indicated that isolates of R. solani from diseased tobacco in North Carolina belong to AG-3. Furthermore, the tobacco isolates, like AG-3 from potato, were prototrophic for thiamine, whereas isolates of AG-2-2 were autotrophic for thiamine. Cluster and principal component analyses based on cellular fatty acids indicated that AG-3 isolates from tobacco were distinct from AG-3 isolates from potato [...]

The Microbial Identification System (Microbial ID, Inc., Newark, DE), used to identify and characterize fatty acids of bacteria, was modified to characterize fatty acids of isolates of Rhizoctonia solani AG-1 IA. The major fatty acid found was linoleic (18:2 cis 9, 12), which constituted 75.3-78.5% of the whole-cell fatty acid content. This fatty acid, along with palmitic (16:0) and oleic (18:1 cis 9), accounted for 95-96% of the C9-C20 fatty acids present. Smaller amounts of nine other fatty acids were consistently identified (...)

Modern rolling stock is significantly quieter, both internally and externally, than previous designs of carriage on British Railways (BR). However, there remains scope for improvement on future builds of vehicle in order to provide a better acoustic environment for passengers. Attention needs to be given, in particular, to the shape of the sound spectrum. This paper discusses the acoustic characteristics which influence passenger comfort and the extent to which a satisfactory acoustic environment is achievable. Sources of internal noise are identified, and the mechanisms by which the sound energy enters the passenger areas are discussed. Measures which can be taken to influence these mechanisms, preferably at the design stage, are indicated.

Problems arise in the use of understory vegetation as an indicator of site condition in that impermanent factors such as microclimate, succession, and chance may play significant roles in determining local composition. Residual ordination analysis is a method which facilitates quantification of the sources of variation in understory vegetation over a landscape. Here it is applied to survey data, representing 250 stands upon which the forest ecosystem classification programme for the Clay Belt portion of northeastern Ontario is based, to test the premise that vegetation types will differentiate soil conditions for forestry purposes. Ordination of the data by detrended correspondence analysis yielded a bivariate scatterplot which, through visual appraisal, seemed readily interpretable in terms of site-related nutrient and moisture gradients. Formal exploration, using canonical redundancy analysis, yielded the following predictive model: understory vegetation (detrended correspondence analysis axes 1 and 2) = soils (67%) + canopy (8%) + succession (1%) + error (24%). Extraction of residual ordinations confirmed this general model and demonstrated that although canopy and successional influences are minor in the data, they are significant. Because the nonsite-related, predictable components account for only 9% of the variation at most, the premise of the existing forest ecosystem classification system is judged to be sound insofar as the data upon which it is based adequately describe the range of commercial stand conditions normally encountered. The results are discussed in relation to vegetation survey design and the performance of residual ordination analysis on a large data set is assessed.

SUMMARY Two field trials showed that initial populations of Tylenchus Bastian, Paratylenchus Micoletzky, Pratylenchus minyus Sher and Allen, P. crenatus Loof, P. penetrans Chitwood and Oteifa, Helicotylenchus pseudorobustus Golden and H. digonicus Perry did not decrease yield of cereals whereas a significant inverse relationship existed between populations of Tylenchorhynchus dubius Filipjev and yield of wheat. T. dubius and Longidorus spp. Filipjev were associated with early leaf-yellowing of barley, though difficulty in controlling nematodes failed to firmly link yield reduction with nematode populations. The possible variability in tolerance of cereals to nematodes is discussed.

SUMMARYNew exposures of Upper Llandovery and Cambrian strata are described from the southern Malvern Hills. The rocks occur in a small faulted outlier between Midsummer and Hollybush Hills, within the main Pre-Cambrian outcrop. The Cambrian is represented by a thin succession of Malvern Quartzite and Hollybush Sandstone and is overlain by an Upper Llandovery limestone with a basal conglomerate containing rounded pebbles of Hollybush Sandstone. The new exposures weaken the case for a major post-Llandoverian fault at the western boundary of the local Pre-Cambrian outcrop, but provide further evidence of an important phase of pre-Llandoverian tectonism in the Malvern area.Faunas of brachiopods, graptolites and conodonts from the Llandoverian limestone allow a correlation with the C5 substage of the shelly sequence, the griestoniensis graptolite zone and a position near the boundary of the celloni and amorphognathoides conodont zones.

A series of 74 cases of meralgia paresthetica is presented. All patients were satisfactorily treated with nonsurgical modalities. A brief review of the etiological factors involved supports the impression that it is an entrapment syndrome related primarily to external pressure against the lateral femoral cutaneous nerve in the region of the anterior superior iliac spine. Though its peripheral symptomatology is relatively straightforward, often associated pain referred to the gluteal area results in an incorrect diagnosis of sciatic radiculopathy due to “disc disease”. The correct diagnosis can be easily made from the relief obtained by injecting the lateral femoral cutaneous nerve with an anesthetic agent.

What are the object properties that serve as a basis for the musical instrument classification system, and how do general and specific experience affect knowledge of these properties? In the first study, the multimodal quality of properties underlying children's and adults' perception was investigated. Subjects listened to solos and identified instruments producing the sounds. Even children who did not have experience with all the instruments correctly identified the family of instruments they were listening to. The hypothesis of the second study, that musical instrument families function as a "basic level" in the instrument taxonomy, was confirmed. Variation in the basic level with varying expertise was documented in the third study with musicians. In the fourth study, children and adults identified the source of sounds from unfamiliar objects, Chinese musical instruments. It is suggested that the concept of affordances may be relevant for understanding the importance for behavior of different levels of abstraction of category systems.

Nitrated polycyclic aromatic hydrocarbons (nitro-PAH) have been detected in the environment, originating from sources such as diesel exhaust emissions and coal combustion fly ash. 1-Nitropyrene (NP) is a predominant mutagenic and carcinogenic nitro-PAH found in diesel exhaust emissions. Since inhalation of NP is a likely route of exposure in humans, it is important to determine the biological fate of inhaled NP both in its pure form and associated with particles. The purpose of this study was to determine the disposition of NP aerosols inhaled by rats. The studies described in this paper were designed to determine the deposition of [14C]NP over a range of exposure concentrations, identify the pathways and half-times for excretion of absorbed NP, and determine the distribution of inhaled NP and metabolites in tissues. Male F344 rats were exposed nose only to various concentrations of NP and NP coated on diesel exhaust particles (50-1100 ng/liter). The results indicate that, over the range of concentrations tested, pathways for excretion of [14C]NP equivalents in urine and feces were independent of the exposure concentration of NP, whether in its pure form or associated with diesel exhaust particles. In all cases, fecal excretion was the major route of elimination of [14C]NP equivalents, with about 2 times more excreted by this route than by urine. The fractional deposition of [14C]NP in the respiratory tract did not appear to be dependent on exposure concentration. Half-times for elimination of 14C in urine and feces were about 15 to 20 hr. In all exposures, 14C was widely distributed in the tissues examined. Analysis of the tissues for NP and its metabolites indicated that within 1 hr after exposure, greater than 90% of the 14C was NP metabolites. Lungs of rats exposed to [14C]NP coated on diesel exhaust particles contained nearly 5 times more 14C than lungs from rats exposed to pure aerosols of [14C]NP (148 vs 29 pmol/g lung) within 1 hr after exposure. This difference was increased to 80-fold at 94 hr after exposure (80 vs 1 pmol/g lung). Long-term clearance half-times of 14C from various tissues were similar. The results demonstrate that particle association of NP significantly alters the biological fate of inhaled NP.