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Studies directed towards the reduction of particle and heat fluxes to plasma facing components by the application of ponderomotive forces generated by radio frequency (RF) are being conducted in TEXTOR. A modified poloidal limiter is used as an antenna with up to 3 kW of RF power; the data obtained show that the plasma is repelled by the RF ponderomotive potential. The density is reduced by a factor of 2–4 and the radial decay length is substantially altered. The density near the limiter decays exponentially with RF power. The electron temperature profile changes, with the decay length becoming longer (almost flat) during the RF. The temperature in the scrape off layer (SOL) increases and its increase is roughly proportional to the RF power until it saturates, suggesting that the heating efficiency drops with power, and that improved performance is to be expected at higher powers.

The purpose of this qualitative study was to explore women's experiences of being a doctoral student. We report on interviews from 11 women, 8 of whom were Caucasian and 3 of whom were African- American. Participants in the study described their experiences as doctoral students in ways that reflected a spiraling process of becoming. This process included experiences of confidence, support and self-discovery. This research has implications for nursing faculty and women engaged in doctoral education as well as for women who anticipate entering doctoral programs.

Transient high heat flux events like ELMs, vertical displacement events and disruptions can cause the thermal ablation of plasma facing material. Until now experimental work in this field had been carried out by exposing material specimens to heat loads by electron or laser beam or by tests in pulsed plasma accelerators. In the present work carbon specimens were directly exposed to intense plasma fluxes in the TEXTOR tokamak. The exposure was performed with a fast probe allowing the insertion of the material over a distance of 9 cm into the edge plasma for a duration of 80 ms. The results of in-situ diagnostic measurements and of the post-experiment examination of the specimens are compared with a reference experiment by electron beam and with numerical analyses. Results indicated that the heat flux to the probe surfaces and the probe erosion is much lower than expected.

Foraging activity of two mid- to low- shore species of limpet, Patella granulans (Prosobranchia) and Siphonaria concinna (Pulmonata) from an exposed shore on the Eastern Cape coast of South Africa was monitored. In both species, activity was compared during spring and neap tides and, in P. granulans between summer and winter. Rhythms of activity of the two species were similar, with foraging excursions being mainly associated with nocturnal low tide times, although some P. granularis foraged during daytime low tides. It is suggested that foraging excursions in P. granularis are triggered by wave action. Both species foraged further on spring tides than on neap tides and this is suggested to be a result of the limited time limpets have to forage. P. granularis was also found to forage further during summer when compared to winter and the possibility that seasonal micro-algal productivity influences foraging distances in limpets is discussed. The foraging activity of both species could be divided into 3 distinct phases, a relatively rapid outward phase, a much slower foraging phase and a rapid homeward phase. Whether or not these limpets graze throughout an excursion is not known. S. concinna was found to home to a fixed scar, although during the experiment some scar-swapping occurred. P. granularis did not home to a fixed scar but possessed a 'home range' (approx. 5 cm2) to which it returned after each excursion. Patella granularis was found to move randomly during foraging, whilst S. concinna foraged in a nonrandom direction .which took individuals upshore. No tidal-influen ce is thought to be present in this case and the possibility of a learning component in the foraging behaviour of certain limpet species in relation to the return to optimal feeding patches is discussed.

The first demonstration of a hollow core photonic bandgap fiber (HC-PBGF) suitable for high-rate data transmission in the 2 µm waveband is presented. The fiber has a record low loss for this wavelength region (4.5 dB/km at 1980 nm) and a >150 nm wide surface-mode-free transmission window at the center of the bandgap. Detailed analysis of the optical modes and their propagation along the fiber, carried out using a time-of-flight technique in conjunction with spatially and spectrally resolved (S2) imaging, provides clear evidence that the HC-PBGF can be operated as quasi-single mode even though it supports up to four mode groups. Through the use of a custom built Thulium doped fiber amplifier with gain bandwidth closely matched to the fiber's low loss window, error-free 8 Gbit/s transmission in an optically amplified data channel at 2008nm over 290m of 19 cell HC-PBGF is reported.

Hermeneutic phenomenological methods were used to explore nurses' perspectives on the phenomenon of end-of-life care within the hospital setting. Three main themes described participants' experiences: "Confronting Challenges," "Coming to Understand End-of-Life Care," and "Transforming the Understanding of End-of-Life Care into Nursing Practice." Recommendations for education, practice, and research were derived.

In the aquatic environment, particles can be broadly separated into phytoplankton (PHY), non-algal particle (NAP) and dissolved (or very small particle, VSP) fractions. Typically, absorption spectra are inverted to quantify these fractions, but volume scattering functions (VSFs) can also be used. Both absorption spectra and VSFs were used to calculate particle fractions for an experiment in Chesapeake Bay. A complete set of water inherent optical properties was measured using a suite of commercial instruments and a prototype Multispectral Volume Scattering Meter (MVSM); the chlorophyll concentration, [Chl] was determined using the HPLC method. The total scattering coefficient (measured by an ac-s) and the VSF (at a few backward angles, measured by a HydroScat 6 and an ECO-VSF) agreed with the LISST and MVSM data within 5%, thus indicating inter-instrument consistency. The size distribution and scattering parameters for PHY, NAP and VSP were inverted from measured VSFs. For the absorption inversion, the "dissolved" absorption spectra were measured for filtrate passing through a 0.2 μm filter, whereas [Chl] and NAP absorption spectra were inverted from the particulate fraction. Even though the total scattering coefficient showed no correlation with [Chl], estimates of [Chl] from the VSF-inversion agreed well with the HPLC measurements (r = 0.68, mean relative error s = −20%). The scattering associated with NAP and VSP both correlated well with the NAP and "dissolved" absorption coefficients, respectively. While NAP dominated forward, and hence total, scattering, our results also suggest that the scattering by VSP was far from negligible and dominated backscattering.

Objective. In a randomized trial of women with early stage breast cancer undergoing adjuvant chemotherapy, two stress management interventions, tai chi training and spiritual growth groups, were compared to a usual care control group, to evaluate psychosocial functioning, quality of life (QOL), and biological markers thought to reflect cancer- and treatment-specific mechanisms.Method. The sample consisted of 145 women aged 27–75 years; 75% were Caucasian and 25% African American. A total of 109 participants completed the study, yielding a 75% retention rate. Grounded in a psychoneuroimmunology framework, the overarching hypothesis was that both interventions would reduce perceived stress, enhance QOL and psychosocial functioning, normalize levels of stress-related neuroendocrine mediators, and attenuate immunosuppression.Results. While interesting patterns were seen across the sample and over time, the interventions had no appreciable effects when delivered during the period of chemotherapy.Conclusions. Findings highlight the complex nature of biobehavioral interventions in relation to treatment trajectories and potential outcomes. Psychosocial interventions like these may lack sufficient power to overcome the psychosocial or physiological stress experiencedduring the chemotherapy treatment period. It may be that interventions requiring less activity and/or group attendance would have enhanced therapeutic effects, and more active interventions need to be tested prior to and following recovery from chemotherapy.

Preparing baccalaureate nursing students to deliver care to an increasingly complex patient population is an ongoing challenge for nursing educators. Wanting to provide their students with a more holistic approach to patient care, undergraduate psychiatric-mental health nursing course faculty created a clinical rotation to address the needs of psychiatric patients who also had 1 or more medical comorbidities. In this article, we describe a pilot project in which students volunteered to participate in a 24-hour clinical experience focused on assessing and addressing the mental health needs of patients admitted to a medical or surgical clinical unit. Evaluation of this approach indicates that the predominant clinical and educational model of specialized healthcare undermines a single course approach to integrated care.

Slope morphology or surface topography greatly affects the stability of slopes with regard to both surficial erosion and mass wasting. Topographic para- meters normally considered in estimating soil erosion losses and calculating short- term mass stability include inclination and length of slope. Most engineered or man- made slopes are planar in form with an unvarying, down-slope gradient and little, if any, plan-form curvature. Natural slopes do not typically exhibit planar slope faces with uniform, un-varying gradients. Instead natural slopes manifest a variety of complex slope forms and profiles. Slopes that start out with planar topography also tend to evolve over time into equilibrium shapes that seldom are entirely planar. This paper describes conceptual and mathematical models, as well as the results of laboratory tests and field observations, that can be used to determine the effect of slope shape on both mass stability and resistance to rainfall erosion. The results of these analyses and observations show that concave slope profiles appear to be more stable and generate less sediment than uniform, planar slopes. These findings are consistent with conceptual models and they also accord with results of computer modeling of soil erosion on slopes with irregular shapes

BACKGROUND. In patients with advanced esophageal adenocarcinoma, the efficacy and palliative role of systemic chemotherapy are not well defined. The primary objective of this Phase II trial was to evaluate the antitumor activity and toxicity of a multiday chemotherapy schedule of high dose cisplatin and etoposide in patients with unresectable or metastatic esophageal adenocarcinoma. A secondary objective was to assess the efficacy of this regimen in palliating dysphagia. METHODS. Twenty-seven eligible patients with unresectable locoregional or metastatic esophageal adenocarcinoma were treated with cisplatin, 30 mg/m 2 /day, and etoposide, 60 mg/m 2 /day, intravenously daily for 5 days, every 3 weeks. After three cycles of chemotherapy, all patients were assessed for response. Patients with responding metastatic disease were given one additional cycle of chemotherapy, and patients with locoregional disease received radiation and concurrent continuous infusion of 5-fluorouracil at 300 mg/m 2 /day for the duration of radiation therapy. Patients were questioned about dysphagia symptoms initially and then weekly during chemotherapy. RESULTS. The major toxicities included myelosuppression, nausea and vomiting, and peripheral sensory neuropathy, with one treatment-related death. Major responses were observed in 13 patients (48% ; 95% confidence intervals, 36-74%), including 5 complete and 8 partial responses. Dysphagia relief occurred in 89% of 18 symptomatic patients within a median time of 16 days. The median survival duration for all patients was 9.8 months, and the actuarial 3-year survival rate was 22%. CONCLUSIONS. Multiday chemotherapy with high dose cisplatin and etoposide is active in patients with advanced esophageal adenocarcinoma. Toxicities associated with this regimen are substantial but manageable.

The signal transduction cascade between the activation of the somatostatin (SOM) receptor and modulation of transmitter release was study using Acetylcholine (Ach) release measurements and patch clamp recordings of Ca2+ current from acutely dissociated St 40 ciliary ganglion neurons. As in intact synapses, somal ACh release was blocked by 100 nM SOM or 100 microM dibutyril cGMP, and the SOM-mediated inhibition could be reversed by 10 microM 1-NAME (a selective inhibitor of nitric oxide synthase, NOS) or 100 microM Rp-8p-CPT-cGMPs (a selective inhibitor of a cGMP protein dependent kinase, PKG). In whole cell recordings, SOM inhibition of Ca2+ current rapidly relaxes to control levels but is sustained in perforated patch recordings which decreases cell dialysis. Inhibition of NOS or PKG in perforated patch recordings, however caused SOM effects to become transient again. We hypothesize that PKG alters the characteristics of the membrane-delimited G protein inhibition of Ca2+ current. Therefore SOM receptors trigger a membrane-delimited signal transduction cascade that is modulated by soluble messengers, converging on voltage activated Ca2+ channels. When both pathways are active together, SOM causes a sustained inhibition of neuronal Ca2+ current leading to a decrease in transmitter release.

The results of a field study of the small-scale spatial structure of the depth of shallow seasonal snowcovers in prairie and arctic environments are presented. It is shown that the spatial distribution of snow depth is fractal at small scales, becoming random at scales beyond some limiting length. This is due to the autocorrelation of depth at small sampling distances. The transition of fractal to random behaviour is indexed by a 'cutoff length', which is defined by the intersection of the 'fractal' slope and horizontal tangent of a logarithmic plot of the standard deviation of depth versus sampling distance. The magnitude of the cutoff length is related to the degree of macroscopic variability of the underlying topography. An increase in length due to the effects of macroscopic topographic variability on snowcover accumulation is confirmed by de-trending field measurements. The de-trended data shown a cutoff length for wheat stubble and fallow surfaces of approximately 30 m, which is consistent with the distance determined from measurements on 'flat' fields. The implications of the transition of snow depth from fractal to random structure on the scales of snow sampling and modelling are presented. The cutoff length may provide a statistic for stratifying shallow snowcovers, by linking snowcover properties to the underlying topography.

A diagnostic capable of providing time resolved measurements of plasma radiated power during disruptions and other fast transients, e.g., edge localized modes has been employed in the DIII-D tokamak. The radiation is detected with absolute extreme ultraviolet (AXUV) photodiode arrays. Thirty chords from a single port provide measurements from a full slice of the plasma at one toroidal location. The analog bandwidth is up to 1 MHz for the brightest events, i.e., disruptions. Active cooling of the diode arrays prevents damage during high temperature vessel baking. Effective responsivity values of 0.12–0.18 A/W are taken from previous work on the application of AXUV diodes in DIII-D. The total radiated energy in disruptions typically agrees with bolometer measurements within about 12%.

We report fabrication of the first low-loss, broadband 37-cell photonic bandgap fiber. Exploiting absence of surface modes and low cross-talk in the fiber we demonstrate mode division multiplexing over three modes with record transmission capacity.

We review our recent progress in the fabrication, characterization, modeling and splicing of wide transmission bandwidth hollow core photonic bandgap fibers and discuss their modal properties and potential for data transmission.

We review our recent progress in the fabrication, characterization, modeling and splicing of wide transmission bandwidth hollow core photonic bandgap fibers and discuss their modal properties and potential for data transmission.

Validation of novel splicing strategy enabling integration of hollow-core photonic band gap fiber with both itself and conventional SMF is presented. Self-splices are robust and low loss (0.16dB). Penalty-free 40Gbit/s data transmission is demonstrated in 1km arrangement of spliced HC-PBGF.

To quantify the renal excretion of atrial natriuretic peptide (ANP) in birds, synthetic ANP was infused intravenously into conscious Pekin ducks at rates of 10, 30 and 90 ng/kg per min for 30 min and the relationships between plasma and urine ANP concentrations were monitored by RIA. The infusions of ANP produced dose-dependent elevations in the plasma concentrations of the hormone; however, urinary concentrations and excretion rates did not change significantly from the basal values of 142·2 ±21·5 pg/ml and 26·4 ± 4·5 pg/min per kg respectively. The metabolic clearance rate of ANP remained constant at each infusion dose (approximately 200 ml/min per kg). The urinary clearance rates ( Journal of Endocrinology (1995) 147, 211–215

Many important food and fibre crops have attained close to their maximum yields as a result of conventional breeding approaches and advances in agronomic and horticultural practices. The manipulation of cell and tissue cultures to produce somatic embryos efficiently is one of the keystones of the new technologies that will greatly alter the way crops are planted (as synthetic seed) and genetically altered in the future. Gene transfer into embryogenic plant cells is already challenging conventional plant breeding, and has become an indispensable tool for crop improvement. This review provides a current assessment of the impact of somatic embryogenesis in agriculture.

The fate of aromatic carbonyl groups during light-induced yellowing of peroxide-bleached mechanical pulps was investigated using infrared and uv-visible reflectance spectroscopies. If the interference of existing carbonyl groups is eliminated by borohydride reduction, both techniques indicate clearly that aromatic carbonyl groups are formed during irradiation. Methoxylated and unmethoxylatedortho-quinones were introduced into the pulp by treatment with sodium periodate or Fremy’s radical. Comparison with pulps which were discoloured by monochromatic near-uv irradiation (λ=320 nm) indicates that both types of quinones are formed during irradiation. The methoxylated quinones were bleached by 420 nm irradiation, but the unmethoxylated quinones seemed instead to sensitize destruction of aromatic groups.

Inductively coupled plasma mass spectrometry (ICPMS) utilizing both hydride generation and conventional nebulization as methods for sample introduction, has been applied to the analysis of Hg in urine and biota at sub μg/g (solid) and sub ng/g (liquid) levels. Concentrations in certified reference materials were determined by standard addition, and isotope ratio measurements were performed to evaluate the potential for applying the methods of isotope dilution mass spectrometry (IDMS) in this area.

New Zealand dairy farmers rely on pasture grazed in situ to feed their herds. Summer is the most difficult period to manage because pasture production is usually highly variable and, in most years, less than herd requirements. Dairy farmers can use a range of options (e.g., summer forage crops, silage) to minimise the impact of both variable and inadequate summer feed supply. Much has been written about recommended procedures for planning and monitoring pasture-based systems, but there is little documentation on the processes actually used by New Zealand dairy farmers. To this end the summer management processes of three high-performing Manawatu seasonal supply dairy farmers were studied over 4 years. The farmers used management systems based on their experience. A range of simple techniques was used to identify potential feed deficits. The farmers then used a set of decision rules to select the best option or combination of options to overcome feed deficits. The study highlighted the potential benefits that could accrue from integrating farmer knowledge with scientific knowledge. Keywords: dairy farmers, decision-making, farmer knowledge, monitoring, summer management

People are using increasing amounts of siloxanes that ultimately end up in landfills and then in landfill gas and biogas digesters. Their presence poses difficulties for industries seeking to utilize the energy content of landfill and biogas, as the combustion process oxidises silicon to silicon dioxide that in turn damages engine parts. Rapid, efficient and accurate methods are needed to quantify their presence.Selected ion flow tube mass spectrometry (SIFTMS) is an emerging real-time technique that has found application for monitoring trace volatiles in air. Samples containing the trace volatiles are simply drawn into the flow tube and convected in a stream of helium. Chemical ionization reactions from mass-selected reagent ions with the volatiles ensue. To quantify the volatiles in the sample, the ion chemistry of the reagent ion with each volatile must be known.Rate coefficients and product ion branching ratios were found for the compounds dodecamethylpentasiloxane, decamethylcyclopentasiloxane, decamethyltetrasiloxane, octamethylcyclotetrasiloxane, triethylsilanol, tetramethylsilane and hexamethyldisilazane.The ion-molecule reactions of the seven silicon-containing compounds examined here were fast, occurring at or near the collision rate, thus allowing for detection at low levels. The very simple reaction chemistry found of proton transfer, electron transfer and methyl loss will enable easy quantitation of the siloxanes in landfill gas and biogas using the SIFTMS technique.

We report transmission of 37 x 40 Gbit/s C-band channels over 250 m of hollow core band gap fibre, at 99.7% the speed of light in vacuum. BER penalty below 1 dB as compared to back-to-back was measured across the C-band.

We study the rich multimode content of an ultra-low loss hollow core photonic bandgap fiber using two complementary techniques which allow us to investigate both short and long propagation distances. Several distinct vector modes are clearly identified, with evidence of low intermodal coupling and distributed scattering.

The first demonstration of a hollow core photonic bandgap fiber suitable for high-rate data transmission at 2µm is presented. Using a custom built Thulium doped fiber amplifier, error-free 8Gbit/s transmission in an optically amplified data channel at 2008nm is reported for the first time.

Experiments have been performed to measure the conductance for backstreaming particles in the throat of the pump limiter ALT-II on TEXTOR under different discharge conditions. The flow inside the throat is analysed by injecting a steady helium flux towards the neutralizer plate and by measuring the helium partial pressure. The amount of helium escaping into the plasma volume has been found to be strongly dependent on the local electron density and electron temperature. At low densities the backstreaming conductance corresponds to the classical value, at medium densities its value is reduced, whereas at the highest densities (>5*1018 m-3) an increasing flow of escaping helium is found. It is shown that a reversal of the plasma flow in the throat of ALT-II can be established by exposing one blade (the other 7 retracted) to high density discharges with additional heating

A numerical model is presented, based on the local volume averaging formulation of transport phenomena in porous media, for simulating meltwater infiltration into unsaturated, frozen soil. With the defined flow and freezing boundary conditions at the snow-soil interface, using the concept of a surface local averaging volume, the time variation in profiles of temperature, liquid / ice content, infiltration / percolation rates, and rate of phase change in upper soil layers are predicted. In addition to a parametric analysis, model estimates of infiltration are compared with quantities calculated from field measurements of soil moisture changes and temperature during snow cover ablation, showing a reasonable agreement.

The interfacing of an electrothermal vaporization (ETV) unit to an inductively coupled plasma mass spectrometer (ICPMS) produces a powerful system for ultra-low-level compositional analysis of micro-volume samples, as well as decreasing some of the molecular interferences inherent in a conventional-nebulization ICPMS. Some problems still remain with this technique in respect to signal variation, sample heating profiles, and instrument tuning parameters. Advances are presented concerning the instrumental conditions necessary for lowering signal variation. These include optimization of “dry-plasma” tuning of the spectrometer lens stack, furnace cooling/heating, and tube mounting. Novel ways of enhancing sensitivity by multiple deposition, preconcentration, and chemical modification have been investigated with particular emphasis on uranium and radium determination.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) has been applied as a method to determine elemental distribution in biological tissue specimens, providing spatial resolution down to 30 μm with the use of an infrared laser beam. Instrument operating parameters such as the laser energy and “dry plasma” tuning have been optimized to provide the high sensitivity and stability required for this type of analysis. In this work, “natural” internal standards (e.g., calcium and magnesium) have been investigated in an effort to establish and minimize the influence of signal variation associated with the instrumentation and the density of the samples themselves. Specimens studied include fish scales (for “elemental tagging”), rat kidney cross sections, and pig femur (to examine variation in the chemistry of the blood/bone interface).

Activation by phenylalanine and reduction by the co-factor (6R)-tetrahydrobiopterin (BH4) are required for formation of active liver phenylalanine hydroxylase. This work describes effects of the activation and redox state on substrate and effector recognition of this enzyme, it establishes relationships among the pterin and phenylalanine binding sites on the different forms of the enzyme, and it provides a quantitative description of the enzyme's presumptive regulatory and catalytic sites. BH4, 7,8-dihydrobiopterin (BH2), 6-methyltetrahydropterin, and 5-deaza-6-methyltetrahydropterin were found to bind to unactivated phenylalanine hydroxylase with a stoichiometry of 1/enzyme subunit and with hyperbolic kinetics; all appear to compete for the same binding site on the enzyme, and all appear to bind in the proximity of, but not to, the enzyme's non-heme iron. In the transition from unactivated to activated enzyme, phenylalanine and pterin binding is modified, a new site for phenylalanine is formed, and the pterin site is replaced by a site of greatly decreased affinity for BH4 and BH2, one which does not appear to recognize the dihydroxypropyl side chain of BH4 and BH2. The pterin- and phenylalanine-binding sites on activated phenylalanine hydroxylase appear to be part of the enzyme's active site. Despite large effects on substrate binding, neither chelator binding ability nor solvent accessibility of the iron are affected by activation; activation appears to affect the nearby environment of the enzyme's iron but not the iron itself. Studies of oxidized and reduced phenylalanine hydroxylase indicate that the redox state is not a major determinant of pterin and phenylalanine association with enzyme.

Effects of phenylalanine and di- and tetrahydropterins on presteady-state and steady-state catalytic behavior of rat liver phenylalanine hydroxylase are analyzed. From this and previous work (Shiman, R, Xia, T., Hill, M., and Gray, D.(1994) J. Biol. Chem. 269, 24647-24656), which analyzed binding of the same compounds to the enzyme in the absence of catalysis, a model of phenylalanine hydroxylase regulation is proposed. The mechanism appears novel in that 1) one substrate, phenylalanine, is a positive effector (activator), 2) a second substrate, (6R)-tetrahydrobiopterin (BH4), is a negative effector that blocks phenylalanine activation by forming an inactive BH4.enzyme complex, and 3) the BH4.enzyme complex sequesters BH4 and controls its metabolic availability. Reaction progress curves showing regulatory effects of BH4, 7,8-dihydrobiopterin (BH2), and phenylalanine are fit by the model with high precision. Data are presented that the high affinity pterin-binding site on unactivated phenylalanine hydroxylase is the pterin site that regulates catalysis. Occupancy of this site by BH4 or BH2 causes non-cooperative, linear inhibition of phenylalanine activation of the enzyme. All inhibitory effects of BH4 appear due to its binding at the pterin regulatory site on unactivated enzyme. BH2 inhibits by binding at the active site as well as the pterin regulatory site. 6-Methyltetrahydropterin also appears to bind at the pterin regulatory site, but its effect is only seen at high phenylalanine concentrations. Using kinetic constants measured in this and earlier work, quantitative effects of phenylalanine and BH4 regulation on the rate of the phenylalanine hydroxylase reaction in vitro and in vivo are calculated. The effects of formation of the BH4.enzyme complex on free BH4 concentration, on enzyme activity, and on regulation of the rate of phenylalanine hydroxylation in liver are discussed.

Egg mass sampling is the primary method for estimating gypsy moth populations in order to make control decisions. The objectives of this research were to determine if there is a significant difference between samples taken when foliage is present or absent, to quantify the difference, and to determine the probability of exceeding an action threshold when samples are taken with foliage present. Fixed- and variableradius plot egg mass samples were taken when foliage was present (summer) and absent (winter) in 136 sample sites in Virginia. The relationship between summer and winter counts was quantified using nonparametric statistics. Winter egg mass counts were 14 to 36% higher than summer egg mass counts. The probability of a summer’s egg mass count exceeding the action threshold was determined by fitting a logistic curve to empirical data for the action thresholds of 618 and 1,236 egg masses per hectare. If samples are taken when foliage is present, egg mass counts need to compensate for differences between summer and winter counts. As an alternative, the probability of a summer egg mass count exceeding an action threshold could be used.

Electrostatic biasing experiments using the Advanced Limiter Test (ALT-II) pump limiter in the TEXTOR tokamak have been carried out with the dual goals of: (a) improving the core plasma confinement in the tokamak and (b) enhancing the performance of the pump limiter. The fully toroidal belt limiter has been biased during both ohmic and neutral beam heated discharges. Both polarities of bias have been applied up to a maximum of +or-500 V with no evidence of impurity accumulation in the central plasma, although applying either polarity of bias to the limiter increases recycling from both the limiter face and the vacuum vessel liner. This in turn results in an increase of the central density. The application of a negative bias to the limiter produces a barrier to radial particle transport in the region between the limiter and the wall. This barrier is not observed in either the no bias or the positive bias case. Neither polarity of limiter bias affects the central plasma energy confinement, apparently because the electric field structure producing the radial barrier is outside the limiter tangency radius. The enhanced recycling, coupled with high edge density, increases the radiated power from the plasma edge and may lower the power flux to the plasma facing surface of the limiter blade. In the case of positive limiter biasing, the pressure in the pumped plasma collection scoops of the limiter increases by approximately 20%, corresponding to a similar increase in the particle removal rare of the pump limiter. The increase in the particle removal rate appears to result from a lower edge electron temperature. This is consistent with the observation of an increase in edge radiated power

Innocent heart murmurs can be identified and distinguished from organic murmurs using only clinical skills. Pulmonary flow murmurs may be differentiated from those of atrial septal defect or pulmonary stenosis by the behavior of the second heart sound, parasternal vibratory murmurs from ventricular septal defect, aortic stenosis and mitral regurgitation by their length and radiation, venous hums from patent ductus arteriosus by maneuvers designed to obliterate the hum, and supraclavicular arterial murmurs from carotid artery bruit, aortic stenosis and coarctation by similar maneuvers and blood pressure recordings. The article outlines the points of differentiation in order to arrive at a firm diagnosis and obviate concern and unnecessary referrals.

New information relating to structure andor wider distributional records are given for four species of Cyperaceae indigenous to Zambia and/or Zimbabwe. Three are members of tribe Cypereae (Sphaerocyperus erinaceus, Cyperus albopilosus, C. ciltochty-socephalus); one of Ficineae (Isolepis trollii). Tribal delimitation follows that of Goetghebeur (1986).

Balloon angioplasty was attempted, using hydrophillic Terumo guidewires, in 52 totally and subtotally occluded coronary arteries (50 patients), in which recanalisation by conventional angioplasty guidewires had failed. Hydrophillic guidewires had a crossing success rate of 65.4% (34/52); there was subsequently a technical success rate of 56% (29/52) and clinical success of 39% (20/52). Dissection of the coronary artery was seen in 16/29 technically successful cases. In 12/16 arteries, dissection was small and localised, whereas in 4/16 large and extended distally. There was one myocardial infarction and no peri-procedural deaths. Eleven out of 29 technically successful cases continued to be regarded as successful 12 mo postangioplasty. We conclude that the hydrophillic Terumo guidewire can improve the success rate in angioplasty of totally and subtotally occluded coronary arteries when conventional wires have failed.

Impurity fuelling has been studied in TEXTOR by gas puffing under a wide range of experimental conditions. First, neon has been injected into discharges with a range of densities during both Ohmic and neutral injection heating. Then, helium, neon and argon have been injected into similar discharges and the increase in radiated power and Zeff studied as a function of the number of impurity atoms injected. Similar experiments using carbon monoxide and methane yielded markedly different results from those of the rare gases. The fraction of injected atoms entering the confined plasma has been estimated and found to vary widely, from less than 1% for carbon to about 100% for helium. Detailed Monte Carlo calculations performed using the LIM code to simulate the impurity behaviour have shown that good agreement with experiment can be obtained for all species except oxygen, where charge exchange processes are thought to be important

Background The treatment of acute, recurrent, and chronic sinusitis remains controversial because of the presence of a wide variety of aerobic and anaerobic bacteria in the sinuses. Design This double-blind, randomized trial compared cefaclor with amoxicillin in the treatment of acute, recurrent, and chronic maxillary sinusitis using clinical evaluation, roentgenography, and microbiologic evaluation of antral aspirates. Setting Outpatient office of five otorhinolaryngologists in Salt Lake City, Utah. Patients One hundred eight adult patients with acute, recurrent, or chronic maxillary sinusitis. Intervention Oral treatment with cefaclor (500 mg) twice daily or amoxicillin (500 mg) three times daily for 10 days. Main outcome measure Clinical response to treatment with cefaclor vs amoxicillin. Results Fifty-six patients with acute sinusitis, 25 with recurrent sinusitis, and 15 with chronic sinusitis were evaluable. Although multiple organisms were common in each group, patients with acute sinusitis were more likely to have Haemophilus influenzae or Streptococcus pneumoniae, and patients with recurrent or chronic sinusitis were more likely to have anaerobes in sinus aspirate. Whether treated with cefaclor or amoxicillin, clinical improvement occurred in 86% of patients with acute sinusitis and 56% of patients with recurrent sinusitis. Patients with chronic sinusitis were too few to allow statistical analysis of the differences in outcome between them and patients with recurrent or acute sinusitis. Resistance of the cultured organisms to the study drug used was unrelated to treatment outcome. Conclusions The rate of clinical improvement was high in patients with acute sinusitis but was less favorable in those with recurrent and chronic disease regardless of the study drug used. The susceptibility of organisms isolated to the study drugs was unrelated to outcome.

Physically based algorithms that estimate saltation, suspension and sublimation rates of blowing snow using readily available meteorological and land use data are presented. These algorithms are assembled into a model, the Prairie Blowing Snow Model (PBSM), and used to describe snow transport on fields in a Canadian Prairie environment. Validation tests of PBSM using hourly meteorological data indicate differences between modelled and measured seasonal snow accumulations between 4 and 13%. Application of the blowing snow model using meteorological records from the Canadian prairies shows that the annual proportion of snow transported above any specific height increases notably with mean seasonal wind speed. An observed decrease in annual blowing snow transport and sublimation quantities with increasing surface roughness height becomes more apparent with higher seasonal wind speeds and temperatures. The annual quantity of snow transported off a fetch increases with fetch length up to lengths of between 300 and 1000 m, then remains relatively constant or slowly declines. Within the first 300 m of fetch 38–85% of annual snowfall is removed by snow transport, the amount increasing with wind speed. Beyond 1000 m of fetch, blowing snow sublimation losses dominate over transport losses. In Saskatchewan, sublimation losses range from 44 to 74% of annual snowfall over a 4000 m fetch, depending on winter climate. Notably, as a result of steady-state transport, the sum of snowcover loss due to blowing snow transport and sublimation does not change appreciably from its 1000 m fetch value for fetches 500 to 4000 m. The transition from primarily transport to primarily sublimation losses at the 1000 m fetch distance may be useful in assessing the effect of scale in snow hydrology.

Information on the temporal variation in snow-covered area of watershed during melt is requisite for accurate predictions of runoff. The amount of the gross watershed area that is snow-covered affects runoff primarily in two ways: a) it influences the melt rate, because patches of bare ground affect the energy balance of the snow field, and b) it governs the contributing area of runoff. This paper examines the area-frequency and perimeter-area characteristics of soil and snow patches that form during ablation of seasonal snowcovers in Prairie and Alpine environments. It uses fractal geometry as a basis for quantifying these properties. Image analyses are applied to aerial photographs taken during snowmelt on two small watersheds: one in the West-central part of the Province of Saskatchewan in the Canadian Prairies, the other in the alpine region of the Austrian Alps. The results of the study suggest that the soil and melting snow patches behave as fractals, that is their perimeter-area and area-frequency characteristics can be described by simple power equations with patch area. The perimeter-area ratio of the soil and snow patches decreases with increasing size of patch, but at a smaller rate than for Euclidean objects. The area-frequency characteristics of snow patches follow a hyperbolic distribution with relatively few large patches and numerous small patches. It is suggested that the soil and snow patches have the same fractal dimension. It is concluded that snow patches are not random and their size distribution is predictable. The variation in the edge length of a snow field per unit basin area during ablation is demonstrated. A maximum value of the ratio is reached when a basin has 45-65 % snowcover. With snow coverage in this range the potential for local advection increasing melt under a specific set of climatic conditions is greatest.

This study focused on the belief of some nurse educators that caring cannot be taught directly and is learned by students from faculty role-modeling and faculty student interactions in clinical, classroom, and other situations. The purpose was to further explore these beliefs to determine if nursing students perceived that they learn caring behaviors through observing role-modeling by faculty, as well as to explore students' perceptions of other means by which they learn about caring. Since opportunities for faculty to model nurse caring behaviors in the clinical setting are varied and serendipitous, a videotaped scenario simulating a patient care situation, using professional actors, was created and shown to nursing students. The videotape was seen by 137 BSN and ADN students who then recorded their perceptions on a two-page open-ended questionnaire developed by the researchers. Results from this study indicated that students do learn about caring from faculty role-modeling, as well as from health care staff they encounter, often in a very paradoxical way. Many interesting and unintended results also occurred through the use of this research approach.

Uniformly 14C-labelled primary cell walls (14C-PCW) were purified from suspension-cultured cells of spinach (Spinacia oleracea L.) grown in a medium containing D-[U-14C]glucose. The approximate polymer composition of the 14C-PCW preparation (% total 14C) was homogalacturonan 30,rhamnogalacturonan 23, xyloglucan 10, other hemicelluloses 3, cellulose 21, lignin 0,14C-labelled protein < 3 and [14C]starch < 2. The degree of methyl esterification of the pectic polysaccharides was about 25%. The 14C-PCW contained about 4% O-acetyl and 3% non-volatile ester-linked residues. When tracer levels of these 14C-PCW were fed to rats, only about 18% of the 14C appeared in the faeces;negligible levels of 14C (0.07%) remained in the gut contents 4 d after feeding. Some 14C was present in the carcass. The results show that U-14C-labelled primary cell walls can be purified and radiochemically analysed by the methods developed here, and that primary cell walls are extensively fermented by the gut microflora of the rat.

Purple coneflower [Echinacea purpurea (L.) Moench] is an increasingly popular crop because of its value in the U.S. botanical industry. At present, there is no rapid method of analyzing it for chicoric acid, the predominant phenolic acid associated with immunostimulation in humans. The objective of this study was to quantify chicoric add in purple coneflower roots by near infrared (NIR) reflectance spectroscopy. One hundred sixty-nine plants were harvested and their root tissues analyzed for chicoric acid by high performance liquid chromatography (HPLC). Root samples were scanned between 1100 and 2498 nm and reflectance data recorded. The HPLC data were regressed against infrared spectra to develop empirical prediction equations. The optimum prediction equation produced coefficients of determination for calibration and cross validation of 0.90 and 0.86, respectively. The mean chicoric acid concentration was 8.29 g kg DM -1 , and the standard errors of calibration and cross validation were 0.89 and 1.06 g kg DM -1 , respectively. We conclude that NIR reflectance spectroscopy can accurately quantitate chicoric acid in purple coneflower.