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In atmospheric science, measurements above the surface have long been obtained by carrying instrument packages, radiosondes, aloft using balloons. Whilst occasionally used for research, most radiosondes – around one thousand are released daily – only generate data for routine weather forecasting. If meteorological radiosondes are modified to carry additional sensors, of either mass-produced commercial heritage or designed for a specific scientific application, a wide range of new measurements becomes possible. Development of add-on devices for standard radiosondes, whilst retaining the core meteorological use, is described here. Combining diverse sensors on a single radiosonde helps interpretation of findings, and yields economy of equipment, consumables and effort. A self-configuring system has been developed to allow different sensors to be easily combined, enhancing existing weather balloons and providing an emergency monitoring capability for airborne hazards. This research programme was originally pursued to investigate electrical properties of extensive layer clouds, and has expanded to include a wide range of balloon-carried sensors for solar radiation, cloud, turbulence, volcanic ash, radioactivity and space weather. For the layer cloud charge application, multiple soundings in both hemispheres have established that charging of extensive layer clouds is widespread, and likely to be a global phenomenon. This paper summarises the Christiaan Huygens medal lecture given at the 2021 European Geoscience Union meeting.

Understanding rainfall in arid and water-scarce regions is central to the efficient use of water resources in agriculture, irrigation, and domestic food security. This work presents a new dataset with which to study precipitation processes in arid regions, utilising two years (2018–2020) of ceilometer observations made at Al Ain International Airport in the desert region of Al Ain, United Arab Emirates (UAE), where the annual rainfall is 76 mm. Ceilometer data provide a novel method by which to study both the evolution of water droplets from the cloud base down to the surface and the local circumstances required for rain to successfully reach the surface. In this work, we explore how successful precipitation depends on the initial size of the droplets and the thermodynamic profile below the cloud. For 64 of the 105 rain events, the droplet diameters ranged from 0.60 to 3.75 mm, with a mean of 1.84 mm. We find that smaller droplets, higher cloud bases, reduced cloud depths, and colder cloud bases all act to prevent successful precipitation, instead yielding virga (28 out of the 105 rain generating events). We identify how these multiple regional factors combine—specifically, we identify clouds deeper than 2.9 km, droplet diameters greater than 2 mm, and a midpoint below-cloud RH profile greater than 50%—to give successful rainfall, which may ultimately lead to more efficient rainfall enhancing measures, such as cloud seeding.

Charging of upper and lower horizontal boundaries of extensive layer clouds results from current flow in the global electric circuit. Layer-cloud charge accumulation has previously been considered a solely electrostatic phenomenon, but it does not occur in isolation from meteorological processes, which can transport charge. Thin layer clouds provide special circumstances for investigating this dynamical charge transport, as disruption at the cloud-top may reach the cloud base, observable from the surface. Here, a thin (~300 m) persistent layer-cloud with base at 300 m and strong wind shear at cloud-top was observed to generate strongly correlated fluctuations in cloud base height, optical thickness and surface electric Potential Gradient (PG) beneath. PG changes are identified to precede the cloud base fluctuations by 2 minutes, consistent with shear-induced cloud-top electrical changes followed by cloud base changes. These observations demonstrate, for the first time, dynamically driven modification of charge within a layer-cloud. Even in weakly charged layer-clouds, redistribution of charge will modify local electric fields within the cloud and the collisional behaviour of interacting charged cloud droplets. Local field intensification may also explain previously observed electrostatic discharges in warm clouds.

Electric charge is always present in the lower atmosphere. If droplets or aerosols become charged, their behavior changes, influencing collision, evaporation, and deposition. Artificial charge release is an unexplored potential geoengineering technique for modifying fogs, clouds, and rainfall. Central to evaluating these processes experimentally in the atmosphere is establishing an effective method for charge delivery. A small charge-delivering remotely piloted aircraft has been specially developed for this, which is electrically propelled. It carries controllable bipolar charge emitters (nominal emission current ±5 μA) beneath each wing, with optical cloud and meteorological sensors integrated into the airframe. Meteorological and droplet measurements are demonstrated to 2 km altitude by comparison with a radiosonde, including within cloud, and successful charge emission aloft verified by using programmed flight paths above an upward-facing surface electric field mill. This technological approach is readily scalable to provide nonpolluting fleets of charge-releasing aircraft, identifying and targeting droplet regions with their own sensors. Beyond geoengineering, agricultural, and biological aerosol applications, safe ionic propulsion of future electric aircraft also requires detailed investigation of charge effects on natural atmospheric droplet systems.

We present an analysis of coronal mass ejections (CMEs) observed by the Heliospheric Imagers (HIs) onboard NASA’s Solar Terrestrial Relations Observatory (STEREO) spacecraft. Between August 2008 and April 2014 we identify 273 CMEs that are observed simultaneously, by the HIs on both spacecraft. For each CME, we track the observed leading edge, as a function of time, from both vantage points, and apply the Stereoscopic Self-Similar Expansion (SSSE) technique to infer their propagation throughout the inner heliosphere. The technique is unable to accurately locate CMEs when their observed leading edge passes between the spacecraft; however, we are able to successfully apply the technique to 151, most of which occur once the spacecraft-separation angle exceeds $180^{\circ }$ 180 ∘ , during solar maximum. We find that using a small half-width to fit the CME can result in inferred acceleration to unphysically high velocities and that using a larger half-width can fail to accurately locate the CMEs close to the Sun because the method does not account for CME over-expansion in this region. Observed velocities from SSSE are found to agree well with single-spacecraft (SSEF) analysis techniques applied to the same events. CME propagation directions derived from SSSE and SSEF analysis agree poorly because of known limitations present in the latter.

To describe a sustainable program of teaching and implementing quality improvement (QI) in a 12-month sleep medicine fellowship.We created a QI curriculum based on Accreditation Council for Graduate Medical Education (ACGME) and American Board of Medical Specialty (ABMS) Part IV Maintenance of Certification (MOC) requirements for QI. Two program faculty with prior QI training volunteered to mentor fellows. Our institution's central QI office houses QI experts who teach QI across the health system. One of these experts, referred to as the "QI consultant," helped us adapt QI teaching materials to include 4 online modules and 5 group sessions. Fellows worked in teams to complete 2 data-guided QI cycles.The curriculum required 29 hours for fellows, 18 hours for faculty, and 55 hours for the QI consultant; now that teaching materials have been created, the QI consultant's involvement will decrease over time. Post-curriculum surveys showed that fellows' knowledge of QI concepts increased, as did their confidence performing QI activities. Fellows' QI projects objectively improved timeliness and quality of care for patients. Sleep medicine fellows and QI faculty mentors evaluated the curriculum positively. The curriculum met ACGME requirements for QI, and fellows and mentoring faculty received ABMS Part IV MOC credit upon completion of the curriculum.A QI curriculum can successfully be implemented into a 12-month sleep medicine fellowship to increase sleep medicine fellows' QI knowledge and confidence, meet ACGME and MOC requirements, and contribute to care of patients with sleep disorders.

Cloud images obtained through a crowd-sourced international observing network suggest a cloud variety that has hitherto not been explicitly classified. This cloud feature shows a roughened base, which, under some solar illumination conditions, provides a particularly dramatic appearance. The growing body of photographic observations have led the World Meteorological Organisation to consider adding ‘asperitas’ to the 2017 edition of the International Cloud Atlas as a new form of supplementary cloud feature. We compare reported sightings with available meteorological data to investigate the conditions that give rise to this newly recognised cloud description.

Context.On 2020 April 19 a coronal mass ejection (CME) was detected in situ by Solar Orbiter at a heliocentric distance of about 0.8 AU. The CME was later observed in situ on April 20 by the Wind and BepiColombo spacecraft whilst BepiColombo was located very close to Earth. This CME presents a good opportunity for a triple radial alignment study, as the spacecraft were separated by less than 5° in longitude. The source of the CME, which was launched on April 15, was an almost entirely isolated streamer blowout. The Solar Terrestrial Relations Observatory (STEREO)-A spacecraft observed the event remotely from −75.1° longitude, which is an exceptionally well suited viewpoint for heliospheric imaging of an Earth directed CME.Aims.The configuration of the four spacecraft has provided an exceptionally clean link between remote imaging and in situ observations of the CME. We have used the in situ observations of the CME at Solar Orbiter, Wind, and BepiColombo and the remote observations of the CME at STEREO-A to determine the global shape of the CME and its evolution as it propagated through the inner heliosphere.Methods.We used three magnetic flux rope models that are based on different assumptions about the flux rope morphology to interpret the large-scale structure of the interplanetary CME (ICME). The 3DCORE model assumes an elliptical cross-section with a fixed aspect-ratio calculated by using the STEREO Heliospheric Imager (HI) observations as a constraint. The other two models are variants of the kinematically-distorted flux rope (KFR) technique, where two flux rope cross-sections are considered: one in a uniform solar wind and another in a solar-minimum-like structured solar wind. Analysis of CME evolution has been complemented by the use of (1) the ELEvoHI model to compare predicted CME arrival times and confirm the connection between the imaging and in situ observations, and (2) the PREDSTORM model, which provides an estimate of theDstindex at Earth using Solar Orbiter magnetometer data as if it were a real–time upstream solar wind monitor.Results.A clear flattening of the CME cross-section has been observed by STEREO-A, and further confirmed by comparing profiles of the flux rope models to the in situ data, where the distorted flux rope cross-section qualitatively agrees most with in situ observations of the magnetic field at Solar Orbiter. Comparing in situ observations of the magnetic field between spacecraft, we find that the dependence of the maximum (mean) magnetic field strength decreases with heliocentric distance asr−1.24 ± 0.50(r−1.12 ± 0.14), which is in disagreement with previous studies. Further assessment of the axial and poloidal magnetic field strength dependencies suggests that the expansion of the CME is likely neither self-similar nor cylindrically symmetric.

Livestock grazing is a prevalent land use in western North American intermountain wetlands, and physical and biotic changes related to grazing-related disturbance can potentially limit wetland habitat value for waterfowl. We evaluated breeding waterfowl use in 34 wetlands in relation to water retention, amount of wetlands on the landscape, and livestock grazing intensity. The study was conducted over 2 years in the southern intermountain region of British Columbia, Canada. For a subset of 17 wetlands, we measured aquatic invertebrate abundance over 1 year. Waterfowl breeding pairs and broods were classified into three functional groups: dabbling ducks, and two types of diving ducks, overwater and cavity nesters. We evaluated candidate models with variables considered singly and in combination using the Akaike Information Criterion. When selected, bare ground (an indicator of grazing intensity) and wetland density were negatively associated with breeding use while wetland fullness and invertebrate density were positively associated. Each factor was a significant predictor in at least one of the models, but unexpectedly, grazing intensity was the most consistent predictor of waterfowl wetland use (e.g., it was present in more ‘best models’ than wetland fullness). Grazing was associated with declines in the number of waterfowl pairs and broods, likely mediated through effects on wetland vegetation and aquatic macroinvertebrates. Models with site- and landscape-scale variables generally performed better than simpler models. Waterfowl breeding use of wetlands can be improved by reduced livestock grazing intensity adjacent to wetlands and by grazing later in the season. Wetland water retention is also an important constraint on waterfowl use of wetlands and may become more limiting with a shifting climate.

The spontaneous combustion of curing hay bales poses serious safety and financial issues to farmers and ranchers across the United States and abroad. The primary cause of this spontaneous combustion is the baling of hay before it has adequately dried and reached a sufficiently low moisture content level. This inadequate drying is primarily due to the farmer allowing the hay to dry in the field after cutting for a given period of time. But unfortunately, this does not always ensure that the hay has sufficiently dried before baling. Spontaneous combustion of hay bales is due to a proliferation of thermophilic bacteria that thrive in a moist and hot environment. If the moisture content of hay is greater than 20%, it provides a suitable environment for mesophilic bacteria, which can heat the hay to as a high as 140°F. Although this is not problematic in and of itself, a 140°F hay bale is a suitable environment for the proliferation of thermophilic bacteria, which can further heat the hay to 170oF. At this temperature, the hay can spontaneous combust, destroying the hay and risking the loss of buildings, equipment, livestock and agricultural workers. To combat this problem, a low-cost, low-power, wireless hay bale status sensor suite has been developed so that the farmer can easily and safely monitor the conditions inside a curing hay bale, to give the farmer time to take action before the bale spontaneously combusts. The battery operated sensor suite has two sensors in contact with the hay inside the bale, a printed circuit board (PCB) moisture content sensor and a discrete temperature sensor. The extremely low-cost of the PCB moisture content sensor is what enables the practicality of the sensor suite. WiFi is used to transmit moisture content and temperature data to the farmer's smartphone when it comes within range. The sensor suite is placed inside the bale at the time of baling. After the bale has fully cured, in four to six weeks, the reusable sensor suite can be removed and used in a new bale.

A miniature field meter is described for measuring fair weather electric fields (of magnitude ~100 Vm-1). It is a brushless field mill constructed from machine-cut parts, driven by a computer fan motor. It resolves fair weather fields at ~1 mV per (Vm−1), with a time response of 0.65 s. It implements self-calibration through combining a mechanical shutter with a programmable bipolar calibration electrode. It has a mass of 86 g, dimensions 4 cm × 4 cm x 8 cm and consumes

This paper presents an electronic implementation of a controller for an exact solvable chaotic oscillator. The controller uses a proportional feedback control scheme to stabilize the chaotic oscillator, with both analog and digital components. The analog hardware implementation uses commercial-off-the-shelf (COTS) digital logic components and an analog feedback path in order to generate a control signal that produces small voltage perturbations in the oscillator’s trajectory. The digital portion of the control effort is contained on a single microcontroller, which contains the information to be encoded into the chaotic oscillator. The perturbations are aperiodically applied using a clock that is generated from the oscillator’s output signal so that the pulses can be applied to the oscillator at the correct times. In order to achieve different stabilized orbits, a variable gain stage was added to the controller, using an operational amplifier and a potentiometer, such that the magnitude of the control pulses can be adjusted. This controller is used to demonstrate stabilization of various periodic orbits in a double scroll exact solvable chaotic oscillator, which is shown in the time domain and in phase portraits. This type of controller could be used to encode information into chaotic waveforms for communication systems.

Calibration of ultralow current ammeters deployed in atmospheric ion counters requires stable current references operating at high source impedance. Using standard precision components, this current reference generates equal bipolar currents of nominally ±500fA, cyclically for 32 s each. The currents were found to be stable to 2 fA over the temperature range - 20 to 20°C, typical of atmospheric conditions. The output current is delivered via a capacitor, and by arranging for the capacitor to be guarded at ground potential when the system is not generating a current, the reference can be permanently connected to an electrometer with minimal leakage. © 2000 American Institute of Physics.

We illustrate how coupling could occur between surface air and clouds via the global electric circuit – through Atmospheric Lithosphere–Ionosphere Charge Exchange (ALICE) processes – in an attempt to develop a physical understanding of the possible relationships between earthquakes and clouds.

This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to the field will benefit from the introductory overviews and can quickly expand their knowledge by studying the subsequent sections.

In the wake of a severe economic crisis in the 1980s Costa Rica abandoned an import substitution model of development adopted in the 1960s and implemented policies supporting foreign investment and the diversification of its exports. This study presents an application of the model proposed by Herzer and Nowak-Lehnmann to test the hypothesis that export diversification has contributed to economic growth in Costa Rica via externalities of learning-by-doing and learning-by-exporting over the period of 1965–2006. After using the autoregressive distributed lags and dynamic ordinary least squares models no long-run relationship was found between export diversification and growth.

Meteorological measurements from Lerwick Observatory, Shetland (60°09′N, 1°08′W), are compared with short-term changes in Climax neutron counter cosmic ray measurements. For transient neutron count reductions of 10–12%, broken cloud becomes at least 10% more frequent on the neutron minimum day, above expectations from sampling. This suggests a rapid timescale (∼1 day) cloud response to cosmic ray changes. However, larger or smaller neutron count reductions do not coincide with cloud responses exceeding sampling effects. Larger events are too rare to provide a robust signal above the sampling noise. Smaller events are too weak to be observed above the natural variability.

Background The assessment of medical trainees is becoming an increasingly prominent issue, with current methods having varying degrees of inherent subjectivity and bias. Cusum analysis is a technique used in quality control systems, and is starting to be employed in medical training. Endobronchial ultrasound (EBUS) is an established tool in the diagnosis and staging of lung cancer, although its use in the UK is currently restricted. As it becomes more widespread, there will be a need to assess trainees9 competence accurately to ensure that those performing EBUS at new centres are appropriately skilled. Methods A retrospective review of clinical practice in tertiary referral centres in England, Scotland and Spain was carried out. The study group comprised 500 patients undergoing EBUS for the diagnosis and staging of lung cancer as part of a clinical service. Using cusum analysis, the first 100 cases from each of the five centres are presented. Each centre has one consultant physician as the primary EBUS operator, and all operators began using EBUS at their current centre (ie, no learning from prior experience). The data are presented as learning curves. Results It is evident that there is a wide range of time over which EBUS-guided transbronchial needle aspiration (TBNA) competence is attained. The pooled sensitivity was 67.4% (individual sensitivities 66.7, 70.7, 61.2, 80.3 and 59.7%). Conclusion Cusum analysis is well suited to the assessment of procedures with a binary outcome, but accurate and appropriate standards of practice must be determined prior to assessment to ensure correct identification of underperformance. This report suggests that the learning curve for EBUS is greater than previously reported using different methods, and that even experienced bronchoscopists vary in their speed of learning.

The solar wind modulates the flux of galactic cosmic rays impinging on Earth inversely with solar activity. Cosmic ray ionisation is the major source of air's electrical conductivity over the oceans and well above the continents. Differential solar modulation of the cosmic ray energy spectrum modifies the cosmic ray ionisation at different latitudes, varying the total atmospheric columnar conductance. This redistributes current flow in the global atmospheric electrical circuit, including the local vertical current density and the related surface potential gradient. Surface vertical current density and potential gradient measurements made independently at Lerwick Observatory, Shetland, from 1978 to 1985 are compared with modelled changes in cosmic ray ionisation arising from solar activity changes. Both the lower troposphere atmospheric electricity quantities are significantly increased at cosmic ray maximum (solar minimum), with a proportional change greater than that of the cosmic ray change.

tionally trusted the safety of their food supply. Historically, more than 80% of consumers in dicated that they are confident in the safety of the food they purchase in a grocery store. How ever, that percentage fell to 66% in 2007, with only 11% being completely confident. Only 43% were confident in the safety of restaurant food in 2007 (Food Marketing Institute 2008, p. 71). The USDA and FDA are entrusted to protect the American public from unsafe food and the accompanying illnesses and death. But in recent years that trust appears to have eroded as the number of food recalls increased 135% from 240 to 565 between 2006 and 2008 (Food Industry Report 2009). A lack of, or decline in, confidence in the safety of food can lead to desperate private ac tions such as extreme diets, nutrition fads, me dia scares claiming to be documentaries, social causes around food and political pressure for more food inspection and government moni toring, trade restrictions, and a demand for lo cal foods. We have seen all of these reactions

The behavior of humans jumping and bobbing on flexible structures has become a matter of some concern for both structural integrity and human tolerance. The issue is of great importance for a number of structure types including stadia terraces. A unique test rig has been developed for exploring the forces, accelerations, and displacements that occur when a human subject jumps or bobs on a flexible structure where motion can be perceived. In tests reported earlier, it was found that the subject is able to generate near resonant structural response but it is extremely difficult, if not impossible, to jump or bob at or very near to the natural frequency of the structure when its vertical motion is significant. Also, under such near-resonant conditions, the force developed by the subject was found to drop significantly. In this paper, the effect of altering the subject-to-structure mass ratio and the damping ratio of the structure on these phenomena is presented. As would be expected, it is shown that as the structure becomes more massive and more highly damped it moves less for nominally the same excitation. In this situation, it becomes easier to jump and bob near to resonance and the degree of force dropout reduces, although it is still significant for even the most massive and highly damped case considered. A method for including these effects of human-structure interaction in a load model for dynamic response calculations is then proposed.

The present study tested if current drug use was related to acculturation (measured by language spoken at home), gender, or youth attitudes towards drugs in a large sample of 8th grade, predominantly Mexican American, Hispanic youth. The data were obtained via self-report survey from 2964 Hispanic youth in 108 schools. Hierarchical linear modeling (HLM) was used to test if acculturation, gender, or youth attitudes towards drugs predicted past 30-day use of alcohol, inhalant, or marijuana use and assess school-level influences. Acculturation and gender interacted with attitudes towards drugs to predict current alcohol use. Gender interacted with attitudes towards drugs to predict current alcohol and inhalant use. Having positive attitudes towards drugs was related to increased substance use for all three drug types. Hispanic eighth grade girls had significantly higher use rates than boys for both alcohol and inhalants. Additional research is needed to better understand the influence of acculturation on substance use among Hispanic youth.

Electricity in the atmosphere provides an ideal topic for educational outreach in environmental science. To support this objective, a simple instrument to measure real atmospheric electrical parameters has been developed and its performance evaluated. This project compliments educational activities undertaken by the Coupling of Atmospheric Layers (CAL) European research collaboration. The new instrument is inexpensive to construct and simple to operate, readily allowing it to be used in schools as well as at the undergraduate University level. It is suited to students at a variety of different educational levels, as the results can be analysed with different levels of sophistication. Students can make measurements of the fair weather electric field and current density, thereby gaining an understanding of the electrical nature of the atmosphere. This work was stimulated by the centenary of the 1906 paper in which C.T.R. Wilson described a new apparatus to measure the electric field and conduction current density. Measurements using instruments based on the same principles continued regularly in the UK until 1979. The instrument proposed is based on the same physical principles as C.T.R. Wilson's 1906 instrument., 11 pages

The continuous-culture pilot plant at Clevedon is based on Monod's large bactogen. The special feature of this type of apparatus is the rotating drum inside the fermenter which insures good aeration and mixing without the incorporation of a sparger. The apparatus is designed for the cultivation of non-pathogens only.

We compared a novel 5% testosterone (T) cream (AndroForte 5, Lawley Pharmaceuticals, Australia) with a 1% T gel (Testogel, Besins Healthcare, Australia). Using an open-label crossover design, subjects were randomized to one of two treatment sequences using either the T gel or T cream first in a 1 : 1 ratio. Each treatment period was 30 days with a 7-14 days washout period between them. On Days 1 and 30 of each treatment period blood was sampled at -15, -5 min, 0, 2, 4, 5, 6, 7, 8, 9, 10, 12 and 16 h post study drug administration. Sixteen men with established androgen deficiency aged between 29 and 73 years, who had undertaken a washout from prior testosterone therapy participated in the study. One subject failed to complete both arms and another was excluded post-completion because of a major protocol violation. Bioequivalence was established based on key pharmacokinetic (PK) variables: AUC, C(avg), C(max), T(max), % fluctuation (with and without baseline correction) for the two formulations of testosterone on Day 1 and Day 30. The ratio and 90% CI of AUC 0.99 (0.86-1.14), C(max) 1.02 (0.84-1.24) and C(avg) 0.99 (0.86-1.14) for T cream/T gel were within the predetermined bio-equivalence criteria of 80% to 125% at Day 30. There were no statistically significant differences between secondary biochemical markers: serum dihydrotestosterone (DHT), oestradiol (E2), sex hormone-binding globulin (SHBG), luteinizing hormone (LH) and (FSH). The two testosterone formulations were shown to be bioequivalent.

PURPOSE To describe change in residents' attitudes toward gifts from and interactions with industry and to measure the effects of a formal educational workshop on changes in perceptions. METHOD At the University of Chicago, 118 internal medicine residents completed an observational survey and took part in a controlled intervention across three years (2001-2004) of residency. Four cohorts of residents completing the program in 2004-2007 participated. The intervention was an interactive educational workshop, including reviews of literature and guidelines, and three videos demonstrating routine resident interactions with pharmaceutical representatives. Residents graduating in 2005 were the intervention group and residents graduating in 2004 the comparison group. Analysis of variance and linear regression models were used to determine the relationship between variables. RESULTS Residents perceived "lunch sponsored at noon conference" and "pharmaceutical representative brief talk at noon conference" as increasingly appropriate over their training period (p < .02). Residents perceived "pens, notepads, pocket antibiotic guides" as increasingly appropriate and "tickets to sporting events," "round of golf," and "travel/registration for national conference" as increasingly inappropriate (p < .05). The intervention group was more likely to rate only one item, "lunch at noon conference," as less appropriate (p = .042). CONCLUSIONS Residents' perceptions toward industry gifts and interactions changed modestly during their training to reflect institutional policy. "Appropriate" gifts of minimal value were generally perceived as increasingly appropriate, whereas "inappropriate" gifts were perceived as increasingly inappropriate over time. An educational workshop alone may not significantly alter residents' perceptions toward industry without the implementation of broad and consistent institutional policy.

During the 14-month period from May 2002 through June 2003, approximately 10% of U+S+ supermarkets began to offer fresh irradiated ground beef under the stores’own labels+ Using a survey of supermarket store managers from this period, the authors investigate the factors that influenced stores’adoption of irradiated ground beef+ Results from the adoption model show that factors associated with competition, merchandising philosophy, and structure in the food retailing industry play a strong role in the decision+Among other results,it was found that variables relating to a competitor’s adoption status and proximity can increase the likelihood of a store’s adoption+ @EconLit citations: L660, M310, Q180# © 2006 Wiley Periodicals, Inc+

Steroid hormones including oestradiol have been identified as non-genetic factors that may influence plasma homocysteine. In advanced assisted reproduction, plasma oestradiol levels fluctuate markedly during the treatment cycle starting with normal followed by sub- and then supra-physiological levels. Because of the diverse harmful effects that hyperhomocysteinaemia has been associated with, it is imperative to understand how it may be manipulated during assisted reproduction. A total of 30 women undergoing treatment for infertility were recruited and followed through an advanced assisted reproduction cycle. Blood samples were analysed for oestradiol, homocysteine, vitamin B12, red cell folate and plasma folate during each phase. All patients had normal vitamin B12 and folate levels. Predictably, oestradiol showed marked changes as patients progressed through each treatment phase. However, there were no corresponding significant fluctuations in plasma homocysteine. Oestradiol concentration does not influence plasma homocysteine in women with normal vitamin B12 and folate levels undergoing advanced assisted reproduction.

Introduction: In 1996 the University of Michigan Health System created the Guidelines Utilization, Implementation, Development, and Evaluation Studies (GUIDES) unit to improve the quality and cost-effectiveness of primary care for common medical problems. GUIDES’s primary functions are to oversee the development of evidence-based, practical clinical guidelines for common medical conditions; measure and provide feedback on physicians’ performance; and facilitate systemic changes to support appropriate care. Various methods are used to improve care, including evidence reviews, formal education, informal clinical “opinion leaders,” feedback, reminders, and procedure changes. Twenty-four common medical conditions have been addressed through this process. More than 30 measures of clinical performance have been developed and reported. Methods: This case study describes a systematic, multifaceted program to improve the quality and cost-effectiveness of primary care. Results: Illustrative results for clinical performance are presented for 2 measures of chronic care, 2 measures of preventive care, and 2 measures of acute care. All 6 measures show general improvement in performance across years, with performance near or above the National Committee for Quality Assurance’s 90th percentile for Health Plan Employer Data and Information Set measures. Discussion: A systematic approach involving all relevant components of a health system integrates the synthesis of information, education about the information and how to implement it, and addressing operational barriers. Benefits include a curriculum that is shared across faculty, residents, and medical students and more uniform quality of care that faculty model for physicians-in-training.

A national survey of broiler industry executives is conducted to analyze site-specific factors related to the broiler-complex location problem. Conjoint analysis is used to analyze the broiler complex location decision. Feed costs, community attitude toward the broiler industry, availability of geographically concentrated growers, unemployment rates, and wage rates were found to be the top five factors affecting broiler company location decisions. The quality of roads between feed mill and growers; electricity, heating, water, and sewage costs; and the number of potential growers in the region were also found to be important.

Conjoint analysis is used to measure the preferences of United States consumers for labeling of biotech foods. The study found that consumers in the sample support mandatory labeling of biotech foods. This suggests that U.S. consumers would support revisions to the present voluntary labeling policy of the U.S. Food and Drug Administration and the U.S. Department of Agriculture. Results also showed that the preferred labeling format is a text disclosure that describes the benefits of biotechnology in combination with a biotech logo.

BACKGROUND Mammography screening rates are below national recommendations for older women. Understanding the relation between the characteristics of primary care physicians (PCPs) and mammography rates for older women can help to target screening improvement efforts. METHODS Subjects were 2527 PCPs practicing in Michigan between 1997 and 1998. A cross-sectional design used Medicare data to identify women age 68 years or older in 1998 whom PCPs treated in 1997–1998 and to determine whether these women had a mammogram between 1996 and1998. Eligible women were Medicare beneficiaries age 65 years or older by 1996, residing in Michigan from 1996 to 1998, without specified comorbidities likely to affect decisions regarding mammography. Correlations and multiple regressions examined the relation between this score and characteristics of both PCPs and their practice populations of older women. RESULTS Mammography rates across physicians' practices ranged from 3–100% (mean = 59%, standard deviation = 17%). Five predictors accounted for 55% of the variance in mammography rates across practices. Higher mammography rates were found to be independently related to physicians who have: a lower mean age for female Medicare patients, a higher mean number of physicians billing for patients' care, a lower mean number of inpatient admissions, obstetrics/gynecology practices, and a higher mean education level in patient's zip code (beta weights ≥ 0.25, P < 0.0001). CONCLUSIONS PCPs vary substantially with regard to mammography rates for older women. Mammography rates vary more with the population of patients in physicians' practices than with commonly measured personal characteristics of physicians. Mammography rates should be adjusted for patient population to target individual PCPs with low mammography rates for interventions. Cancer 2003. © 2003 American Cancer Society.

A disposable backscatter instrument is described for optical detection of cloud in the atmosphere from a balloon-carried platform. It uses an ultra-bright light emitting diode (LED) illumination source with a photodiode detector. Scattering of the LED light by cloud droplets generates a small optical signal which is separated from background light fluctuations using a lock-in technique. The signal to noise obtained permits cloud detection using the scattered LED light, even in daytime. The response is interpreted in terms of the equivalent visual range within the cloud. The device is lightweight (150 g) and low power (∼30 mA), for use alongside a conventional meteorological radiosonde.

Background: Endoscopy is now a routine part of the work-up for many patients with gastrointestinal symptoms. Adults tolerate these procedures well, with either no sedation or a relatively light level. In contrast, children often require deep sedation or a general anesthetic to successfully perform these procedures. Therefore, pediatric endoscopies may require more time, personnel, and monitoring equipment to provide optimal conditions for the patient. The goals of this retrospective case series were to describe the anesthesia times and recovery duration of the different procedures, the types and amounts of medications commonly used, and the types and rates of complications experienced. Methods: Patients (2,306) who underwent endoscopy in the Arkansas Children's Hospital endoscopy suite during a 4-year period were identified. A random sample of 720 charts was reviewed retrospectively. Results: Patients ranged in age from younger than 1 year to 29 years. Patients most often had abdominal pain or multiple gastrointestinal symptoms. Sixty-eight percent of patients underwent esophagogastroduodenoscopies; 30% colonoscopy or a combination of the two. Ninety-five percent of patients received a propofol-based anesthetic. Midazolam, fentanyl, and alfentanil were frequently used as supplemental agents. Complications occurred infrequently and were airway related. All complications were easily treated, with no adverse sequelae. Conclusions: This model of anesthesiologist-provided sedation/anesthesia for gastrointestinal endoscopy procedures has been extremely successful in the Arkansas Children's Hospital and has served to heighten awareness of many issues surrounding sedation and anesthesia outside of the operating room, while ensuring a high level of care is provided.

The complexity of analog VLSI systems is often limited by the number of pins on a chip rather than by the die area. Currently, many analog parameters and biases are stored off-chip. Moving parameter storage on-chip could save pins and allow us to create complex programmable analog systems. In this paper, we present a design for an on-chip nonvolatile analog memory cell that can be configured in addressable arrays and programmed easily. We use floating-gate MOS transistors to store charge, and we use the processes of tunneling and hot-electron injection to program values. We have fabricated two versions of this design: one with an nFET injection mechanism and one with a pFET injection mechanism. With these designs, we achieve greater than 13-bit output precision with a 39-dB power-supply rejection ratio and no crosstalk between memory cells.

The aim of this study was to assess the process and outcome of hospitalised patients (inpatients) for whom whole-body CT was requested but not performed. For 6 months the reasons why CT was not performed were recorded, together with relevant discussions with clinicians. Subsequent referrals for alternative investigations were noted. The eventual outcome of the patients was monitored via the patients' records. Eighty-three (8%) of 1001 inpatient requests were identified for which body CT was not performed after an electronically generated request. Fifty-five requests were not accepted by the radiology department during the vetting process for a variety of reasons (often more than one): criteria used for rejection often overlapped and included referrals outside national guidelines (n = 20), better alternative investigations (n = 29), time constraints (n = 19), over-zealous requests (n = 17) and clinicians' erroneous interpretation of preceding imaging investigations (n = 9). Sixteen CT exams were cancelled by a clinician. An additional 12 exams were not performed for miscellaneous non-medical reasons. In no case could a patient's death be ascribed to CT not being performed. Most (981 of 1001, 98%) CT requests comply with current guidelines, disproving a perception that many radiological referrals are inappropriate. In our health care system radiologists have to turn down some appropriate CT referrals due to a lack of CT capacity. Although lack of CT contributed to delay in diagnosis, no patient died as a direct result of not having CT.

Objective: To gather information about healthcare providers' beliefs regarding pain and its treatment in children with cognitive impairment. Design: A survey consisting of two acute pain vignettes (a child undergoing surgery and a child undergoing an outpatient medical procedure) was completed by 440 nurses and 146 physicians at Arkansas Children's Hospital. Respondents completed one of four different surveys that systematically varied the child's level of cognitive impairment (none, mild, moderate, severe) in both vignettes. Questions addressed expected pain, pain assessment methods, pharmacologic regimens, and nonpharmacologic interventions. Results: In general, provider discipline and level of cognitive impairment did not significantly influence responses about pain experience and treatment. Potent analgesia, regularly scheduled dosing, and nonpainful administration were selected most frequently. Self-report of pain, patient-controlled analgesia, and behavioral interventions requiring higher cognitive skills were selected less frequently for children with more severe cognitive impairment. Conclusions: The presence of cognitive impairment appeared to influence provider decisions regarding the appropriateness of specific pain assessment and treatment methods requiring skills on the part of the child. Overall, healthcare provider views regarding analgesia and sedation were similar for all children, regardless of impairment. Whether these beliefs are consistent with clinical practice is yet to be documented.

A case of cholecystobronchial fistula secondary to adenomyomatosis of the gallbladder is described. A cholecystobronchial fistula is a very unusual cause of fistulation between the bronchial and biliary tree. This is only the fifth reported case in the English language literature.

Air is a safe and effective natural contrast agent in neonatal high gastrointestinal (GIT) obstruction. Successful early decompression often results in plain abdominal radiographs of low diagnostic yield. We present a series of neonates with high GIT obstruction in whom air-augmented abdominal radiographs (AAAR) were performed instead. Fourteen neonates presented with suspected high GIT obstruction. In 12 sick babies, obstruction was confirmed and the level of obstruction was determined. The other two neonates required additional positive contrast upper GIT studies. These confirmed small bowel malrotation. For neonatal high GIT obstruction an AAAR can provide a rapid and accurate diagnosis. Positive contrast agent studies should be performed when the AAAR is non-diagnostic.

Measurements of carbon monoxide, nitrogen oxides, PM10, sulphur dioxide and ozone from four UK National Automatic Urban Network Stations have been analysed for the year 1994. All of the sites are urban background, with two in the same city (Birmingham Centre and Birmingham East) and the other two also in cities in the centre of England, Leicester and Leeds, respectively 58 and 154 km from Birmingham. Expressed as cumulative frequency distributions and median concentrations, the pollution climates of the four sites are relatively similar, with differences between Birmingham Centre and Birmingham East as large as those between Birmingham and the other cities. Sulphur dioxide, which does not have an appreciable road traffic source, behaves differently, especially in Leeds, which is adjacent to a number of major point sources. However, when monthly hourly maxima and exceedences of health-related threshold concentrations are examined, the sites behave differently and relationships between them are much poorer,...

The U.S. sugar industry has historically been insulated from volatilities in the world sugar market through the use of an import quota. Recent occurrences in the international agricultural policy arena have brought the need to examine the competitiveness of the United States sugar industry to the fore. Developments with respect to international agricultural policies, combined with a restructuring of United States domestic agricultural policy will undoubtedly reshape the environment in which the U.S. Sugar industry operates. This paper seeks to answer how the various regions and sectors will be able to compete in the world market. This paper starts by outlining an analytical framework to examine the impact of various sources that influence competitiveness in the sugar industry and identify several indicators of competitiveness.

This article discusses strategies to improve the competitiveness of agribusiness firms through enhanced customer value. Relationships between customer value and factors that influence the cost structure of the firm are discussed. The relationships between customer value and product differentiation, vertical coordination, niche marketing, total quality management, and related strategies are explored. Finally, implications for managerial decisions in the food and agribusiness sector are presented. © 1997 John Wiley & Sons, Inc.

A ±300 V dynamic range, battery-powered, and inexpensive electrometer system is described that has been used with passive horizontal wire antennas to measure the atmospheric electric potential at 1 and 2 m above the earth’s surface. Input currents drawn by the electrometer circuit are of order femtoamperes, and a guard drive output is provided to minimize leakage. The implementation of the passive wire antenna is described, using rigorous insulation and signal guarding, together with results obtained in fair weather conditions. Linearity of the portable electrometer over the input range is demonstrated to be comparable with a commercial laboratory electrometer, and the antenna potential can be determined to within a few volts in the fair weather electric field. Several such portable systems can be cheaply combined, sharing a common high tension supply, to measure the profile of the atmospheric electrical potential above the surface, at a remote site. Damage to the electrometer sustained in electrical storms can be cheaply repaired.

The importance of high value products as a component of United States agricultural output has increased significantly in recent years. Moreover, high value products as a percentage of U.S. agricultural exports have also risen (Burfisher and Missiaen, 1990). Given these trends, it is not surprising that agribusiness competitiveness has become a topic of much discussion in both the popular press and in academic literature. Its importance is also evidenced by initiatives set forth by the Western Regional Coordinating Committee on Agribusiness Research Emphasizing Competitiveness and the International Agricultural Trade Research Consortium symposium Competitiveness in International Food Markets. More recently, the National Association of State Universities and Land Grant Colleges' Board on Agriculture endorsed the Agricultural Competitiveness Initiative (ACI). This initiative calls on land‐grant universities to consider new paradigms for conducting research, extension, and teaching on the issue of U.S. agricultural competitiveness.

The evaluation methodology used most frequently in conjunction with continuing medical education (CME) activities is the written questionnaire. This article helps CME administrators identify when a questionnaire study is likely to be simple and straightforward, when a study is likely to be complex and require experts, and when there are major problems that are likely to prevent a successful study from being performed. Specific steps are detailed for performing a study using a written questionnaire. As an example, the steps in developing our institution's course evaluation questionnaire are described. Suggestions are made for identifying local consultants in research methods and for reference texts about questionnaire studies.