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Accurate helium White Dwarf (DB) masses are critical for understanding the star’s evolution. DB masses derived from the spectroscopic and photometric methods are inconsistent. Photometric masses agree better with currently accepted DB evolutionary theories and are mostly consistent across a large range of surface temperatures. Spectroscopic masses rely on untested He i Stark line-shape and Van der Waals broadening predictions, show unexpected surface temperature trends, and are thus viewed as less reliable. To test this conclusion, we present in this paper detailed He i Stark line-shape measurements at conditions relevant to DB atmospheres (T electron ≈12,000–17,000 K, n electron ≈ 1017 cm−3). We use X-rays from Sandia National Laboratories’ Z-machine to create a uniform ≈120 mm long hydrogen–helium mixture plasma. Van der Waals broadening is negligible at our experimental conditions, allowing us to measure He i Stark profiles only. Hβ, which has been well-studied in our platform and elsewhere, serves as the n e diagnostic. We find that He i Stark broadening models used in DB analyses are accurate within errors at tested conditions. It therefore seems unlikely that line-shape models are solely responsible for the observed spectroscopic mass trends. Our results should motivate the WD community to further scrutinize the validity of other spectroscopic and photometric input parameters, like atmospheric structure assumptions and convection corrections. These parameters can significantly change the derived DB mass. Identifying potential weaknesses in any input parameters could further our understanding of DBs, help elucidate their evolutionary origins, and strengthen confidence in both spectroscopic and photometric masses.

New technologies combined with improved genetics and farmer access are important components required to improve productivity and efficiencies of cropping systems. The ability of the public and private sector to provide these components to farmers often vary considerably and can be challenging because of limited resource allocation and investment in institutions designed to provide these services. Partnerships among national programs where resources are limited and external entities can provide an effective platform to deliver improved cultivars and production and pest management practices that increase crop yield and economic viability of resource-poor farmers. In this note, we describe a partnership between the Council for Scientific and Industrial Research-Crops Research Institute (CSIR-CRI) in Ghana, the International Center for Research in the Semi-Arid Tropics (ICRISAT), the US Agency for International Development Peanut Collaborative Research Support Program (USAID Peanut CRSP), the Feed the Future Innovation Lab on Peanut Productivity and Mycotoxin Control (PMIL), and North Carolina State University (NCSU) that resulted in the release of two ICRISAT-derived lines as cultivars to farmers in Ghana. The cultivars Otuhia (Arachis hypogaea L.) and Yenyawoso (Arachis hypogaea L.) were released by CSIR-CRI in 2012 following evaluations of breeding lines beginning in 1999. This case study provides insight into the research focus and timeline that occurred with this partnership during the research and development process. A portion of the data obtained to support release of these cultivars is provided.

Plasma density measurements are key to a wide variety of high-energy-density (HED) and laboratory astrophysics experiments. We present a creative application of photonic Doppler velocimetry (PDV) from which time- and spatially resolved electron density measurements can be made. PDV has been implemented for the first time in close proximity, [Formula: see text] cm, to the high-intensity radiation flux produced by a z-pinch dynamic hohlraum on the Z-machine. Multiple PDV probes were incorporated into the photoionized gas cell platform. Two probes, spaced 4 mm apart, were used to assess plasma density and uniformity in the central region of the gas cell during the formation of the plasma. Electron density time histories with subnanosecond resolution were extracted from PDV measurements taken from the gas cells fielded with neon at 15 Torr. As well, a null shot with no gas fill in the cell was fielded. A major achievement was the low noise high-quality measurements made in the harsh environment produced by the mega-joules of x-ray energy emitted at the collapse of the z-pinch implosion. To evaluate time dependent radiation induced effects in the fiber optic system, two PDV noise probes were included on either side of the gas cell. The success of this alternative use of PDV demonstrates that it is a reliable, precise, and affordable new electron density diagnostic for radiation driven experiments and more generally HED experiments.

Observations of terrestrial analogs are critical to aiding planetary mappers in interpreting surface lithologies on other planets. For instance, the presence of ignimbrites on Mars has been debated for over three decades and is supported by analogy with deposits on Earth. Critical evidence includes the geomorphic and surface expression of the deposits, and those in the Central Andes of South America are amongst the most-cited analogs. Herein we describe some prominent surface textures and patterns seen in ignimbrites on the scale of high-resolution remotely sensed data (10–1 m per pixel). These include pervasive joints and fractures that contribute to yardang form and development as well as prominent mounds, fissures, and fracture networks (“spiders”, “bugs”, “boxworks”) on ignimbrite surfaces. While all these features are related to intrinsic cooling and degassing processes, the involvement of external water buried by hot pyroclastic flows enhances fumarolic activity, advective cooling, and joint development. Observations of these geomorphic expressions using remote sensing are only possible with the highest resolution data and limited surface erosion. For Mars, where similarly high resolution datasets are available (for example, the High Resolution Imaging Sensor Experiment or HiRISE) extensive dust cover may limit the recognition of similar features there. However significant relief on some of these features on Earth indicate they might still be detectable on Mars.

Butzler, T. M., Bailey, J., and Beute, M. K. 1998. Integrated management of Sclerotinia blight in peanut: Utilizing canopy morphology, mechanical pruning, and fungicide timing. Plant Dis. 82:1312-1318. Sclerotinia blight of peanut, caused by Sclerotinia minor, generally becomes severe only after vines meet in the row middles and a dense canopy develops. Dense foliage appears to support a microclimate conducive to the colonization of peanut limbs by S. minor. Removal of excess foliage before and during a Sclerotinia blight epidemic on the susceptible genotype NC 7 has been shown to reduce the rate of disease progress. Field tests in 1993 and 1994 examined control of Sclerotinia blight among four peanut genotypes (NC 7, VA 93B, NC Ac 18016, and Tamspan 90) with diverse canopy morphologies. Each cultivar had foliage pruned with a rotary mower once (1993 and 1994) or twice (1994) during the season. Applications of fluazinam (9.2 kg a.i./ha) were imposed on the genotype ◊ pruning treatments. Soil temperatures under the canopy of each genotype and pruning treatment were measured and compared. Disease data were collected weekly by counting the number of feet of plants exhibiting lesions with visible fungus growth. Tamspan 90, a resistant Spanish peanut, had the least Sclerotinia blight incidence. Pruning measurably affected soil temperature for approximately 2 weeks following pruning. Removal of foliage reduced disease and increased disease control affected by fluazinam in fields with high disease pressure. In some tests, yields were increased by pruning through a reduction in disease pressure. Yields were lower when peanuts were pruned excessively, especially late in the season. Pruning of excessive vine growth can be an alternative, or complement, to fungicide treatments when done in midseason during favorable weather when moderate to high disease pressure occurs.

Virginia-type peanut (Arachis hypogaea) cultivars were monitored for incidence of Tomato spotted wilt virus (TSWV) and abundance of Frankliniella fusca, the tobacco thrips, in North Carolina during 1995 and 1996. A preliminary evaluation of 225 peanut genotypes for TSWV-resistant or -tolerant genotypes was conducted in 1995. The incidence of TSWV in cultivar NC-9 was twice that of cultivar NC-V11. In 1996, field trials designed to evaluate TSWV susceptibility were conducted with three widely grown commercial peanut cultivars in North Carolina. They were NC-9, NC-V11, and NC-12C, a newly released cultivar. A randomized complete block design was utilized at three locations. Disease incidence was evaluated weekly from 2 weeks postplanting until 2 weeks prior to harvest. Mechanical inoculation of the three cultivars resulted in no difference in relative leaf virus titer as determined from optical density readings following DAS-ELISA for 4 successive weeks beginning at 13 days postinoculation. NC-9 ranked highest in incidence of disease (7%), followed by NC-12C (6%) and NC-V11 (5%). Thrips counts were greatest on NC-V11, followed by NC-9 and NC-12C. Disease incidence overall was 5.96%, but ranged from 3.08 to 11.15% among the three sites. Yield was affected by the temporal occurrence of symptoms beginning at the fifth week postplanting. Greatest yield losses occurred in those plants with the earliest visible foliar symptoms.

Sclerotinia minor, a soilborne fungal pathogen of peanut, can cause serious yield loss in North Carolina. A field test was implemented to study genotype reaction, and the effect of aciben-zolar-S-methyl (a plant activator) and the fungicide fluazinam on disease incidence. In all, 13 genotypes in 1997 and 12 genotypes in 1998 were evaluated. Three applications of acibenzolar-S-methyl (0.14 kg a.i./ha) or fluazinam (0.58 kg a.i./ha) were made on a calendar-based schedule. Disease ratings were made weekly in 1997 and every other week in 1998. Fluazinam suppressed disease at all sites and increased yield at two of three locations. Acibenzolar-S-methyl had no effect on disease incidence or yield. The advanced breeding line N92056C and cvs. Tam-run 98 (TX 901417) and Perry (N93112C) had moderate to high levels of resistance to S. minorand produced high yields compared with susceptible cv. NC 7. Lines derived from wild species also demonstrated moderate to high levels of resistance relative to NC 7 and represent potential breeding lines.

Volcanoes often erupt explosively and generate a variety of hazards including volcanic ash clouds and gaseous plumes. These clouds and plumes are a significant hazard to the aviation industry and the ground features can be a major hazard to local communities. Here, we provide a chronology of the 2009 Redoubt Volcano eruption using frequent, low spatial resolution thermal infrared (TIR), mid-infrared (MIR) and ultraviolet (UV) satellite remote sensing data. The first explosion of the 2009 eruption of Redoubt Volcano occurred on March 15, 2009 (UTC) and was followed by a series of magmatic explosive events starting on March 23 (UTC). From March 23–April 4 2009, satellites imaged at least 19 separate explosive events that sent ash clouds up to 18 km above sea level (ASL) that dispersed ash across the Cook Inlet region. In this manuscript, we provide an overview of the ash clouds and plumes from the 19 explosive events, detailing their cloud-top heights and discussing the variations in infrared absorption signals. We show that the timing of the TIR data relative to the event end time was critical for inferring the TIR derived height and true cloud top height. The ash clouds were high in water content, likely in the form of ice, which masked the negative TIR brightness temperature difference (BTD) signal typically used for volcanic ash detection. The analysis shown here illustrates the utility of remote sensing data during volcanic crises to measure critical real-time parameters, such as cloud-top heights, changes in ground-based thermal activity, and plume/cloud location.

Summary Ten horses were used in a crossover study to evaluate the effectiveness of eltenac against endotoxaemia. Eltenac (0.5 mg/kg bwt) or saline control was given i.v. then 15 min later, intravenous infusion of endotoxin was begun and continued for 120 min (total dose 100 ng/kg bwt). Horses were monitored for heart and respiratory rates, pulmonary and carotid arterial pressure and core body temperature. Blood was sampled at intervals for measurement of haematological variables and plasma concentrations of lactate, prostanoid metabolites, tumour necrosis factor (TNF) and stress hormones. In comparison with saline-treatment, use of eltenac significantly protected against endotoxin-induced changes in respiratory rate, core temperature, systemic arterial blood pressure (SAP), pulmonary arterial pressure, PCV, and plasma protein, 6-keto prostaglandin F1α, thromboxane B2, epinephrine, and cortisol concentrations. Despite statistical effect of eltenac on SAP, values in both treatment groups remained well above baseline throughout the evaluation period. Significant protective effect of eltenac was not found for heart rate, white blood cell count, plasma lactate concentration or TNF activity. On the basis of these results, it is expected that use of eltenac will provide clinical benefit in horses with naturally occurring endotoxaemia.

We analyzed intentional exposures to prescription opioids (buprenorphine, fentanyl, hydrocodone, hydromorphone, morphine, methadone and Oxycodone) using the Research Abuse, Diversion and Addiction-Related Surveillance System (RADARS) Poison Center data over a 5 year period 2003-2007 to see if there were temporal trends in the abuse and misuse of prescription drugs associated with (1) weekends vs. weekdays and (2) during select holiday periods vs. non-holiday periods. Over the study period 25 of 120 holiday period days showed a decrease of at least 1 SD from the mean and 9 of 120 holiday period days showed an increase of at least 1 SD from the mean. Over the study period there were 144,653 intentional exposures. Mean percent of cases by day of week ranged from 14.03% to 14.39%, with slightly higher use on weekend days. There was no significant difference when evaluating prevalence of intentional exposures by day of week (p = 0.99). There was no significant difference when evaluating weekend versus weekday (p > 0.05). In summary, the prevalence of abuse and misuse of prescription drugs was not impacted by day of the week or difference between weekday and weekend. The impact of 8 traditional holidays appeared to be associated with a minor decrease in abuse and misuse of prescription drugs. No temporally related increase in abuse and misuse of prescription drugs was noted and conversely a trend toward decreased abuse and misuse of prescription drugs was suggested.

Volcanic eruptions produce ash clouds, which are a major hazard to population centers and the aviation community. Within the North Pacific (NOPAC) region, there have been numerous volcanic ash clouds that have reached aviation routes. Others have closed airports and traveled for thousands of kilometers. Being able to detect these ash clouds and then provide an assessment of their potential movement is essential for hazard assessment and mitigation. Remote sensing satellite data, through the reverse absorption or split window method, is used to detect these volcanic ash clouds, with a negative signal produced from spectrally semi-transparent ash clouds. Single channel satellite is used to detect the early eruption spectrally opaque ash clouds. Volcanic Ash Transport and Dispersion (VATD) models are used to provide a forecast of the ash clouds' future location. The Alaska Volcano Observatory (AVO) remote sensing ash detection system automatically analyzes satellite data of volcanic ash clouds, detecting new ash clouds and also providing alerts, both email and text, to those with AVO. However, there are also non-volcanic related features across the NOPAC region that can produce a negative signal. These can complicate alerts and warning of impending ash clouds. Discussions and examples are shown of these non-volcanic features and some analysis is provided on how these features can be discriminated from volcanic ash clouds. Finally, there is discussion on how information of the ash cloud such as location, particle size and concentrations, could be used as VATD model initialization. These model forecasts could then provide an improved assessment of the clouds' future movement.

There are over 100 active volcanoes in the North Pacific (NOPAC) region, most of which are located in sparsely populated areas. Dispersion models play an important role in forecasting the movement of volcanic ash clouds by complementing both remote sensing data and visual observations from the ground and aircraft. Puff is a three-dimensional dispersion model, primarily designed for forecasting volcanic ash dispersion, used by the Alaska Volcano Observatory and other agencies. Since early 2007, the model is in an automated mode to predict the movement of airborne volcanic ash at multiple elevated alert status volcanoes worldwide to provide immediate information when an eruption occurs. Twelve of the predictions are within the NOPAC region, nine more within the southern section of the Pacific ring of fire and the others are in Europe and the Caribbean. Model forecasts are made for initial ash plumes ranging from 4 to 20 km altitude above sea level and for a 24-h forecast period. This information is made available via the Puff model website. Model results can be displayed in Virtual Globes for three-dimensional visualization. Here, we show operational Puff predictions in two and three-dimensions in Google Earth®, both as iso-surfaces and particles, and study past eruptions to illustrate the capabilities that the Virtual Globes can provide. In addition, we show the opportunity that Google Maps® provides in displaying Puff operational predictions via an application programming web interface and how radiosonde data (vertical soundings) and numerical weather prediction vertical profiles can be displayed in Virtual Globes for assisting in estimating ash cloud heights.

Satellite images and ground-based observations were used to investigate the morphology and origin of valleys and ridges across large ignimbrite provinces around La Pacana Caldera, N. Chile. We studied 12 separate sites that included five different ignimbrite units that range in age from ∼ 5.6 ± 0.5 Ma to 1.35 ± 0.15 Ma. Over 400 features from within these study sites were quantified. Study sites typically have dimensions of 25 × 35 km. Measurements were made using Landsat TM, ETM+, and SRTM-derived DEM and Shaded Relief images. Morphological measurements were made of the ridges and channels, including the direction of regional slope, length, orientation and gradient of each feature. A classification of the different ignimbrite erosion influences, resulting in varying landscape morphologies identified 4 landscape types; Fluvial, Eolian, Modified and Complex. We conclude that the most prevalent features are fluvial-derived channels but the most distinctive are linear, wind-derived ridges. The orientation of these ridges suggests that strong uni-directional winds from the northwest have been constant over a long period of time (> 1 My).

Assessing the effects of invading species on native community structure is often confounded by environmental factors and weakened by lack of replicated, long-term pre- and post-invasion monitoring. Here, we uncouple the community effects of a freshwater amphipod invader from environmental differences. In Irish rivers, the introduced Gammarus pulex replaces the native Gammarus duebeni celticus. However, the River Lissan in Northern Ireland is dissected by a weir that has slowed the upstream invasion by G. pulex. This allowed us in 2000 to sample three contiguous 150-m reaches that were (1) G. pulex dominated; (2) mixed Gammarus spp.; and (3) G. duebeni celticus only. In 2003, we resampled these reaches and one additional of mixed Gammarus species and one with only G. duebeni celticus further upstream. In temperature, conductivity, and pH, there were statistically significant but no biologically relevant differences among the five reaches of 2003, and between the three reaches surveyed in both years. Although there was evidence of recovery in macroinvertebrate diversity and richness in invaded reaches between years, continued upstream invasion was associated with sustained reductions in these community metrics as compared to un-invaded sites. Community ordination indicated (1) different associations of community composition attributed to the distribution, abundance, and biomass of the invader; and (2) increasing similarity of invaded communities over time. The impact mechanisms of G. pulex on macroinvertebrate community composition may include predation and competition. The consequences of the observed community changes for ecosystem functioning require further investigation.

Research was conducted in North Carolina to compare tobacco thrips (Frankliniella fusca Hinds) control, early season peanut emergence and growth, and pod yield with combinations of the insecticide acephate, inoculant containing Brady rhizobium, and the fungicide tebuconazole applied in the seed furrow during planting. Although interactions among treatment factors were significant, greater control of tobacco thrips damage was noted when acephate was applied and in some cases when tebucanozole was applied. Tebucanzole-treated peanut emerged more slowly than peanut not receiving tebucanazole. Delayed emergence of tebuconazole-treated peanut most likely resulted in emergence when fewer tobacco thrips were present in fields. Peanut pod yield was affected by acephate, inoculant, and tebuconazole independently. Applying acephate and inoulcant increased pod yield in two and three of five experiments, respectively. Pod yield was lower in one of five experiments when tebuconazole was applied. These data su...

Sclerotinia blight, caused by Sclerotinia minor, is an important disease of peanut in North Carolina. The effectiveness of Coniothyrium minitans, a mycoparasite of sclerotia of Sclerotinia spp., was studied in a 5-year field experiment and in eight short-term experiments in northeastern North Carolina. The 5-year experiment was initiated in November 1999 to evaluate the effectiveness of repeated soil applications of C. minitans (commercial formulation, Contans WG) at 2 and 4 kg ha-1 in reducing Sclerotinia blight. In addition, individual commercial peanut fields were selected in 2001 and 2002 to evaluate a single application of C. minitans at 4 kg ha-1. No differences were found between the 2 and 4 kg ha-1 rates of C. minitans in reducing Sclerotinia blight. In 2002, there was less disease in plots receiving applications of C. minitans for either 1 or 3 years compared with the nontreated control; whereas, in 2003, C. minitans applications for 1, 2, or 3 years reduced disease and the number of sclerotia isolated from soil. A single application of C. minitans reduced sclerotia in only two of the eight short-term experiments. The integration of consecutive years of soil applications of C. minitans at 2 kg ha-1 with moderately resistant cultivars and fungicide applications may aid in the management of Sclerotinia blight in peanut.

A survey to document peanut farmers' weed management practices was conducted in the Ashanti, Brong Ahafo, Eastern, and Volta regions of Ghana, West Africa during 2001. Peanut was planted as the only crop in 64% of fields surveyed. Land preparation method was related to land tenure system. The slash and burn system constituted 72% of farmers surveyed. In Brong Ahafo region, 80% of the farmers planted on ridges while peanut was planted flat primarily in the Volta region. Planting flat or on ridges was variable in Ashanti and Eastern regions. Cogongrass [Imperata cylindrical (L.) Beauv.] was ranked as the worst weed by 41% of farmers. Wild poinsettia (Euphorbia heterophylla L.) was ranked second by 38% of farmers. Difficulty in weeding, interference with peanut, rapid growth, and profuse seeding were reasons given by farmers for ranking these weeds as the two most pernicious in Ghana. Weed control was perceived as poor by 65% of farmers, fair by 24% of farmers, and good by 12% of farmers. Sixty-nine...

The invasive North American amphipod Gammarus tigrinus is successfully established in Lough Neagh, Northern Ireland. Gammarus tigrinus is increasingly recognized as having significant predatory impacts on macroinverebrates, contrary to the accepted functional feeding group status of Gammarus species. The native opossum shrimp Mysis relicta overlaps in habitat use with G. tigrinus. However, its interaction with benthic macroinvertebrates is rarely appreciated. Mutual predatory interactions between G. tigrinus and M. relicta were assessed in a series of laboratory experiments. Gammarus tigrinus actively preyed on adult and juvenile M. relicta at a range of spatial scales. Females and recently molted M. relicta were particularly vulnerable to predation. Mysis relicta did not prey on adult G. tigrinus, but rapidly eliminated juvenile G. tigrinus in microcosms. Changes in dissolved O2 saturation did not alter the predatory interaction between these species. Microhabitat use by M. relicta was altered in...

An open channel lava flow on Mt. Etna (Sicily) was observed during May 30–31, 2001. Data collected using a forward looking infrared (FLIR) thermal camera and a Minolta-Land Cyclops 300 thermal infrared thermometer showed that the bulk volume flux of lava flowing in the channel varied greatly over time. Cyclic changes in the channel's volumetric flow rate occurred over several hours, with cycle durations of 113–190 min, and discharges peaking at 0.7 m3 s−1 and waning to 0.1 m3 s−1. Each cycle was characterized by a relatively short, high-volume flux phase during which a pulse of lava, with a well-defined flow front, would propagate down-channel, followed by a period of waning flow during which volume flux lowered. Pulses involved lava moving at relatively high velocities (up to 0.29 m s−1) and were related to some change in the flow conditions occurring up-channel, possibly at the vent. They implied either a change in the dense rock effusion rate at the source vent and/or cyclic-variation in the vesicle content of the lava changing its bulk volume flux. Pulses would generally overspill the channel to emplace pāhoehoe overflows. During periods of waning flow, velocities fell to 0.05 m s–1. Blockages forming during such phases caused lava to back up. Occasionally backup resulted in overflows of slow moving ‘a‘ā that would advance a few tens of meters down the levee flank. Compound levees were thus a symptom of unsteady flow, where overflow levees were emplaced as relatively fast moving pāhoehoe sheets during pulses, and as slow-moving ‘a‘ā units during backup. Small, localized fluctuations in channel volume flux also occurred on timescales of minutes. Volumes of lava backed up behind blockages that formed at constrictions in the channel. Blockage collapse and/or enhanced flow under/around the blockage would then feed short-lived, wave-like, down-channel surges. Real fluctuations in channel volume flux, due to pulses and surges, can lead to significant errors in effusion rate calculations.

Ninety farmers from three villages in the Ejura-Sekyedumasi district of the Ashanti Region of Ghana were surveyed during September 2003 to determine practices used to produce peanut. Surve...

A survey was conducted during 1999 and 2001 in Ashanti, Brong Ahafo, Eastern, and Volta regions of Ghana, West Africa, to identify nematode pests of peanut (Arachis hypogaea L.). Information from the survey is being used to formulate appropriate integrated pest management (IPM) strategies for peanut production in these regions. Ten genera of plant parasitic nematodes belonging to three Orders were identified. Population density and distribution of genera varied in the four peanut-growing regions. Six genera, Helicotylenchus, Meloidogyne (juveniles), Paratrichodorus, Pratylenchus, Rotylenchulus, and Xiphinema were found in all four regions. Hoplolaimus was found only in the Eastern region. Trichodorus and Tylenchorhynchus were absent from Ashanti and Brong Ahafo regions but present in Eastern and Volta regions. Nematode genus Rhignema of the Order Rhigonematida was isolated from millipedes sampled from the rhizosphere of peanut. Twenty-one peanut cultivars and experimental lines were assembled fro...

Late leaf spot is one of the important factors limiting peanut productivity in Ghana. It is essential to demonstrate the extent of yield losses caused by leaf spot and to develop suitable crop management practices. The objectives of this research were to study the effects of time of sowing, cultivar lifecycle, and fungicide sprays on disease incidence, biomass and pod yield of peanut crops grown under rainfed conditions in northern Ghana. Two peanut cultivars, Chinese (90 days duration) and F-mix (120 days duration) were grown for three seasons (1999–2001) at Nyankpala and for two seasons (2000, 2001) at Wa with three sowing dates (early, mid and late, relative to start of rainy season) with (+F) and without (−F) fungicide application. Disease rating, main-stem defoliation, total biomass, pod yield and seed yield were recorded at harvest maturity. Early sowings soon after onset of rains resulted in greater biomass and pod yields compared to late sowing for both cultivars. The long duration cultivar F-mix produced greater yields than short duration cultivar Chinese under both with and without fungicide treated environments. However, incidence and severity of disease, as measured by disease scores and main-stem defoliation at the end of season, were similar in both cultivars. This suggests that the greater yield obtained by the long duration cultivar was not due to disease tolerance or escape but due to its longer growing season. Application of foliar sprays of fungicide was effective in controlling leaf spot and improved peanut biomass and pod yields by 39% and 75%, respectively, when averaged across cultivars and years. Long duration cultivar F-mix, sown early and treated with fungicide under optimum and timely crop management practices, produced 4500–5000 kg ha −1 pod yield over five site years, i.e. more than three to four-fold increase over present average yields in Ghana.

Effusion rate and degassing data collected at Mt. Etna volcano (Italy) in 2001 show variations occurring on time scales of hours to months. We use both long- and short-term data sets spanning January to August to identify this variation. The long data sets comprise a satellite- and ground-based time series of effusion rates, and the latter include field-based effusion rate and degassing data collected May 29–31. The satellite-derived effusion rates for January through August reveal four volumetric pulses that are characterized by increasing mean effusion rate values and lead up to the 2001 flank eruption. Peak effusion rates during these 23–57 day pulses were 1.2 m3 s−1 in Pulse 1 (1 Jan–4 Mar), 1.1 m3 s−1 in Pulse 2 (5 Mar–21 Apr), 4.2 m3 s−1 in Pulse 3 (24 Apr–18 Jun), 8.8 m3 s−1 in Pulse 4 (23 Jun–16 Jul), and 22.2 m3 s−1 during the flank eruption (17 Jul–9 Aug). Rank-order analysis of the satellite data shows that effusion rate values during the 2001 flank eruption define a statistically different trend than Etna's persistent activity from Jan 1 to Jul 17. Data prior to the flank eruption obey a power-law relationship that may define an effusion rate threshold of ∼3–5 m3 s−1 for Etna's typical persistent activity. Our short-term data coincide with the satellite-derived peak effusion period of Pulse 3. Degassing (at-vent puff frequency) shows a general increase from May 29 to 31, with hour-long variations in both puff frequency and lava flow velocity (effusion rate). We identify five 3–14 h degassing periods that contain 26 shorter (19–126 min-long) oscillations. This variation shows some positive correlation with effusion rate measurements during the same time period. If a relationship between puff frequency and effusion rate is valid, we propose that their short-term variation is the result of changes in the supply rate of magma to the near-vent conduit system. Therefore, these short-term data provide some evidence that the clear weeks- to months-long variation in Etna's effusive activity (January–August 2001) was overprinted by a minutes- to hour-scale oscillation in shallow supply.

Experiments were conducted during 2001 and 2002 at one location in North Carolina to compare development of early leaf spot (Cerco-spora arachidicola Hori), pod yield, and market grade characteristics when peanut (Arachis hypogea L.) was grown under overhead sprinkler irrigation (OSI) and subsurface drip irrigation (SDI) and fungicides were not applied or applied biweekly or based on weather advisories. Incidence of early leaf spot was lower when peanut was grown under SDI compared with OSI when fungicides were not applied. Fewer fungicide applications were needed when applications were based on weather advisories rather than when applied biweekly. There was no difference in early leaf spot control or leaf defoliation resulting from disease when fungicides were applied regardless of irrigation system or fungicide application approach. Pod yield was higher in 2001 under SDI compared with OSI when fungicides were not applied; yield was similar in 2002. Disease severity was much higher in 2001 than in 2002 and most likely explains differences in pod yield between years. No difference in yield was noted when fungicides were applied, regardless of irrigation system. The percentage of extra large kernels (%ELK) was lower in 1 of 2 yr under SDI compared with OSI. There were no differences in percentages of fancy pods (%FP), sound splits (%SS), and other kernels (%OK) among irrigation systems and fungicide programs. In a separate experiment where fungicides were applied biweekly, pod yield, %FP, and %ELK were similar under SDI and OSI but greater than nonirrigated peanut. The %OK was lower when peanut was irrigated.

Experiments were conducted from 1999 through 2002 in North Carolina to compare interactions of planting pattern, plant population, and irrigation on peanut (Arachis hypogaea L.) pod yield and market grade characteristics. In additional experiments, pod yield and severity of tomato spotted wilt tospovirus associated with the cultivars NC-V 11, NC 12C, VA 98R, and Perry were compared in single row (rows spaced 91 cm apart) and standard twin row (two rows spaced 18 cm apart on 91-cm centers) planting patterns when peanut was dug and vines inverted on two digging dates spaced 10 to 16 d apart. In a third set of experiments, pod yield, market grade characteristics, and severity of tomato spotted wilt tospovirus were compared when the cultivars NC-V 11 and Perry were planted in single row, standard twin row, and narrow twin row (two rows spaced 18 cm apart on 46-cm centers) planting patterns. Peanut pod yield was higher in standard twin row planting patterns than when grown in single row planting patterns in some but not all experiments. Planting peanut in the narrow twin row pattern did not increase peanut pod yield over the standard twin row planting pattern. Less tomato spotted wilt was observed in standard or narrow twin row planting patterns compared with single row planting patterns. Planting peanut in single rows spaced 46 cm apart did not improve yield over peanut planted in single rows spaced 91 cm apart or the standard twin row planting pattern, regardless of irrigation treatment.

Field experiments were conducted in North Carolina during 2001 and 2002 to evaluate the impact of cultivar and plant population on the incidence of symptoms of tomato spotted wilt virus, which is transmitted primarily by tobacco thrips [Frankliniellafusca (Hinds) (Thysanoptera: Thripidae)]. Treatments included the Virginia market-type cultivars Gregory, NC-V 11, and Perry seeded at in-row plant populations of 7, 13, and 17 plants/m. In these experiments, there was a consistent trend for increased foliar injury from thrips as plant population decreased. Less thrips feeding injury was noted for Gregory and Perry than for NC-V 11. Incidence of visual symptoms of spotted wilt (SW) was recorded from mid-June through mid-September. A plant condition rating was recorded late in the season. Consistent with the results for thrips-induced injury, the percentage of plants infected with SW and the plant condition rating increased as plant population decreased. Gregory had the lowest SW incidence, while NC-V 11 was intermediate between Gregory and the most susceptible Perry. Establishing higher plant densities and planting Gregory rather than NC-V 11 or Perry reduced SW incidence and plant condition rating. Gregory had consistently the highest %ELK (extra large kernels) and %FP (fancy pods) across treatments and locations whereas no definitive trend in market grade characteristics were noted among treatments. In some cases, Perry had a higher incidence of SW, but still had higher pod yields than NC-V 11 with a lower incidence of SW. However, in most cases pod yield correlated with plant condition ratings, and as thrips injury increased, pod yield decreased.

The inhalation of carbon dioxide (CO2) is commonly used in patients and volunteers as a means of producing anxiety or panic. It is generally believed that patients with panic disorder are more vulnerable to the effects of CO2 than patients with other anxiety disorders or healthy volunteers and there is speculation and debate as to the mechanism for this apparent sensitivity. Recent work from our group has shown that a single inhalation of 35% CO2 activates the hypothalamic-pituitary-adrenocortical (HPA) axis, increases blood pressure (BP) and increases subjective fear responses in healthy volunteers. Correlation analyses reveal a relationship between the changes in BP and the cortisol increase. These findings led us to postulate that a common mechanism may mediate these and the subjective responses to inhalation of CO2. We propose that the noradrenergic system, particularly the locus coeruleus (LC), but including the A1 and A2 cell groups, may be a key mediator of these responses. This article examines the evidence and discusses the results of studies from our laboratory in relation to a neuroanatomical model centring on the LC.

Peanut (Arachis hypogaea L.) in the United States is generally grown in conventionally tilled systems. However, interest in reduced tillage peanut production has increased. Five experiments were conducted in North Carolina to determine if cultivar selection and digging date affected peanut yield and economic value when peanut was seeded into conventionally tilled seedbeds compared with strip tillage into small-grain cover crop or stubble from the crop planted the previous summer. In separate experiments, peanut yield and economic value in these tillage systems were compared with peanut strip-tilled into beds prepared the previous fall (stale seedbeds). Cultivar selection and digging date did not affect pod yield or gross value when comparing tillage systems. Pod yield in conventional and stale seedbed systems was similar in all five experiments where these systems were compared, and yields in these tillage systems exceeded those of strip tillage into crop stubble in three of five experiments. Pod yield was similar among all three tillage systems in the other two experiments. In experiments where only conventional tillage and strip tillage systems were compared, pod yield was similar between the two tillage systems in four experiments, higher in conventional tillage compared with strip tillage in one experiment, and higher for strip tillage compared with conventional tillage in one experiment. In 16 of 17 comparisons, pod yield of peanut planted in conventional tillage systems equaled or exceeded that of peanut planted into stubble from the previous crop.

Overwintering of Frankliniella fusca (Hinds), tobacco thrips, in North Carolina and their subsequent spring movement into peanut fields were evaluated using two winter sampling techniques and three spring sampling techniques at the Peanut Belt Res. Sta., Lewiston, NC. In the spring of 1992 and 1993, for 14 d following peanut planting, the aerial movement of tobacco thrips was monitored using cylindrical sticky traps, trap plants, and exclusion cages. Frankliniellafusca were trapped significantly more often at 0.2 m and 0.9 m than at 1.8 m and during the afternoons. Thrips catch was significantly influenced by prevailing wind direction. No thrips were caught on sticky traps on days when maximum temperatures did not exceed 18.7 C. Frankliniella fusca began to colonize emerging peanut plants as they cracked the soil surface on days when there were temperatures above 18.7 C and times when there was no precipitation. Aerial F. fusca movement was monitored with sticky traps for three consecutive winters during 1993–96. Tobacco thrips were collected on sticky traps throughout the winter; however, counts were lower in months and years with lower temperatures. Tobacco thrips, caged throughout the winter with peanut plants infected with tomato spotted wilt virus (TSWV), were analyzed for the presence of a nonstructural protein (NSs) encoded for by the small RNA of TSWV and infectivity by ELISA. A total of eight tobacco thrips were collected, of which one tested positive.

Research was conducted in North Carolina at two locations from 1997 through 2000 to determine net returns of 10 cropping systems during a 4-yr cropping cycle that included peanut (Arachis hypogaea L.), cotton (Gossypium hirsutum L.), soybean [Glycine max (L.) Merr.], and corn (Zea mays L.). Cylindrocladium black rot [caused by Cylindrocladium parasiticum] (CBR) increased when soybean was included in the rotation sequence or when peanut was grown continuously. The CBR-resistant cultivar NC 12C increased yield compared with the susceptible cultivar NC 7 when this disease was present. Cotton was a better rotation crop than corn at one of two locations with respect to peanut yield and gross economic value in the final year of the study. Net returns were substantially lower when peanut was marketed for export in the current federal program rather than at the quota price. However, the profitability ranking among cropping systems changed little regardless of marketing system. Crop yield and net return were influenced by crop selection, weather conditions, and commodity prices during the 4 yr.

The laser flow microfluorometer (FMF) can determine the amounts of certain components in single cells at sample rates of several thousand cells per second. This technique has been employed to characterize Bacillus subtilis populations in batch fermentations with different inocula. Protein and nucleic acid distributions obtained by FMF analyses at different times during the batch have been decomposed using an optimized fit of summed subpopulation distributions. The results of these decomposition calculations, some of which have been approximately confirmed by independent microscopic observations, indicate that the relative numbers of single rods, cell chains, spores, and swollen rounded cells change dramatically during the entire fermentation including the stationary phase. The dynamics of these subpopulations may be related to secondary metabolite production.

There is evidence that active, pre-emergence maternal brood care in amphipod crustaceans may be associated with ‘harsh’ environmental conditions. We examined, in the rockpool amphipod Apherusa jurinei, behavioural activities that may function as a form of active brood care. Only ovigerous females showed ‘curl’ and ‘stretch’ activities, with consequent flushing of the brood pouch and cycling of the eggs therein. There was a significant decline in these activities as embryonic development advanced and brood care almost ceased when well-developed embryos showed a heart pulse and self-ventilation. We propose that this pattern of brood care reflects changes in the physiological requirements of embryos as they develop within the egg membrane. In addition, ovigerous females showed significantly higher levels of brood care under lowered oxygen conditions. They achieved this by increasing the average duration of the ‘stretch’ component, with other brood care components remaining constant. Thus, developmental and environmental cues alter the components of active brood care in distinct ways. Experimental removal showed that the physical presence of eggs in the brood pouch is important in controlling the expression of brood care activities. However, females with all of their eggs removed continued to brood at low levels, suggesting that a maternal state also controls brood care. The sophisticated expression of active maternal brood care in amphipods under ‘harsh’ environmental conditions such as rockpools has implications both for individual reproductive success and the distribution and abundance of brooding versus nonbrooding species. Copyright 2002 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour

Excessive vegetative growth of peanut (Arachis hypogaea L.) can make digging and inverting operations less efficient. Reducing vine growth by applying a suitable plant growth regulator would be an efficient way to manage peanut vines. Pod yield, market grade factors, and gross economic value of peanut treated with prohexadione calcium (calcium salt of 3,5-dioxo-4 propionylcyclohexanecarboxylic acid) were evaluated at 19 sites in North Carolina during 1999 and 2000. Experiments were also conducted at two locations each during 1999 and 2000 to determine the effect of prohexadione Ca, digging date, and lifting (shaking peanut vines after digging to remove soil before combining) on combined yield, market grade factors, gross economic value, seed germination, and pod loss of the virginia market-type cultivar NC 12C. Prohexadione Ca at 140 g a.i. ha -1 , applied at 50% row closure and repeated 2 wk later, increased row visibility at harvest, pod yield by 310 kg ha -1 , and gross economic value of quota peanut by $223 ha -1 when pooled over 19 sites. Prohexadione Ca increased combined yield by 220 kg ha -1 and decreased percent pod loss by 4% regardless of digging date and lifting treatment compared with nontreated peanut. Prohexadione Ca did not affect maximum yield (sum of pods remaining in soil and on the soil surface and pods that were combined) or germination of peanut seed. These data suggest that increased combined yield noted following application of prohexadione Ca can be partially attributed to decreased pod loss.

A variety of pesticides and foliar fertilizers are applied to emerged peanut. Defining interactions among these agrichemicals is important when formulating pest management and production strategies. Research was conducted in North Carolina during 1999 and 2000 to evaluate interactions among prohexadione calcium at 140 g ai/ha applied with various commercially available fungicides, insecticides, herbicides, and foliar fertilizers. Agrichemical mixtures were applied when peanut vines reached 50% row closure. Prohexadione calcium alone was applied approximately 2 wk later. Twenty-eight percent urea ammonium nitrate was included with prohexadione calcium. In a second set of experiments, control of pitted morningglory (Ipomoea lacunosa L.) and yellow nutsedge (Cyperus esculentus L.) by imazapic plus 2,4-DB, acifluorfen plus bentazon plus 2, 4-DB, bentazon plus 2, 4-DB, acifluorfen plus 2,4-DB, pyridate plus 2,4-DB, and 2,4-DB applied alone or with prohexadione calcium were evaluated. Large crabgrass [Digitaria sanguinalis (L.) Scop.] control by sethoxydim and clethodim alone or with prohexadione calcium was evaluated also. Fungicides, insecticides, and foliar fertilizers did not affect efficacy of prohexadione calcium with respect to visible injury to peanut, row visibility, or maintenance of short stems. Slightly higher injury was noted when acifluorfen, acifluorfen plus bentazon, bentazon, and pyridate were applied with prohexadione calcium. Minor increases in pitted morningglory control and peanut injury were noted when herbicides were applied with prohexadione calcium, most likely due to presence of urea ammonium nitrate. However, prohexadione calcium did not affect large crabgrass control by sethoxydim or clethodim. Collectively, these data suggest that prohexadione calcium and the majority of agrichemicals applied to peanut are compatible.

Refining and implementing the Tavistock principles for everybody in health care {#article-title-2} The ethicist Will Gaylin argued that healthcare reform often fails because it attempts technical solutions to ethical problems.1 Agreeing with this position, the Tavistock Group tried to develop ethical principles that might be useful to everybody involved in health care.2–6 They were intended for those who are responsible for the healthcare system, those who work in it, and those who use it. This article describes the origins of the principles, discusses the thinking behind them, considers how they might be used, provides case studies, and reflects on where the venture might go now. #### Summary points The problems of health systems are in the last analysis ethical. Who will live, who will die, and who will decide and how? The ethical codes of individual professions may be divisive rather than helpful The Tavistock principles are intended to provide an ethical compass for all those involved in health care, including patients and owners of health systems The principles cover rights, balance, comprehensiveness, cooperation, improvement, safety, and openness Experience of using the principles is limited and not always encouraging; research is under way on how to implement and “validate” them The idea that it might be useful to develop ethical principles for everybody involved in health care stemmed from the recognition that much of health care is multidisciplinary yet ethical codes usually cover only one discipline.2 The codes may thus be used as ammunition in interdisciplinary battles rather than as tools to think about deep problems. We advanced the idea of developing ethical principles for everybody in the BMJ in 19972 and then convened a group to develop some principles. The Tavistock Group, a collection of people with long experience of health care and ethical debate, developed the principles, which they published in 1999. 3 4 The principles are …

Seedborne Cylindrocladium parasiticum has been reported in peanuts and the possibility of seed transmission postulated; however, seed transmission has not been documented. Cinnamon brown speckles on peanut testae were correlated with isolation of C. parasiticum. Microscopy indicated that seed were colonized by cinnamon brown colored hyphae and microsclerotia interspersed in and on lightened areas of testa. Speckled seed from commercial seed lots (cultivars NC 7, NC 10C) were planted, with or without a chemical seed treatment (1992, captan + carboxin + dicloran [45:18:15% of product]; 1993 to 1995, captan + PCNB + carboxin [45:15:10% of product]), in fumigated fields with no history of peanut production. Asymptomatic seed from noninfested seed lots (cultivar NC-V 11 or NC 7) were checks for soilborne inoculum. C. parasiticum was isolated from all symptomatic seed lots prior to planting (percentage ranged from 4 to 45%) but was not isolated from asymptomatic seed. Seed transmission occurred from seed both with chemical seed treatment (0.25 to 2.75%) and without seed treatment (0.25 to 6.0%), but not in all years. Asymptomatic seed planted 2.5 cm from speckled seed increased the number of plants with Cylindrocladium black rot from two- to sixfold, illustrating the ability of disease to spread from colonized seed to uninfected plants. It was concluded that seed transmission of C. parasiticum is an important means by which this disease is spread within the seed industry.

The 100 ns, 20 MA pinch-driver Z is surrounded by an extensive set of diagnostics. There are nine radial lines of sight set at 12° above horizontal and each of these may be equipped with up to five diagnostic ports. Instruments routinely fielded viewing the pinch from the side with these ports include x-ray diode arrays, photoconducting detector arrays, bolometers, transmission grating spectrometers, time-resolved x-ray pinhole cameras, x-ray crystal spectrometers, calorimeters, silicon photodiodes, and neutron detectors. A diagnostic package fielded on axis for viewing internal pinch radiation consists of nine lines of sight. This package accommodates virtually the same diagnostics as the radial ports. Other diagnostics not fielded on the axial or radial ports include current B-dot monitors, filtered x-ray scintillators coupled by fiber optics to streak cameras, streaked visible spectroscopy, velocity interferometric system for any reflector, bremsstrahlung cameras, and active shock breakout measurement of hohlraum temperature. The data acquisition system is capable of recording up to 500 channels and the data from each shot is available on the Internet. A major new diagnostic presently under construction is the BEAMLET backlighter. We will briefly describe each of these diagnostics and present some of the highest-quality data from them.

Research was conducted in North Carolina and Virginia from 1997 through 1999 to compare runner and virginia market-type peanuts as influenced by cultivar selection, fertility practices, and pest management strategies. The runner market-type cultivar Georgia Green yielded and provided gross market value equivalent to the virginia market-type cultivar NC-V11 under a wide range of edaphic and environmental conditions. Calcium (as gypsum) applied at initial pegging increased the percentage of extra large kernels, the percentage of total sound mature kernels, and market value (c/kg) of the virginia market-type cultivar Gregory. The runner market-type cultivars Georgia Green and GK-7 were less responsive to calcium. Response of both market types was dependant upon environmental conditions. Pest management strategy affected pod yield, gross value, and economic return of peanut similarly for both virginia and runner market types. Results from these studies suggest that runner market-type peanut can provide pod yield, gross value, and economic returns similar to commonly grown virginia market-type peanut when grown in the Virginia-Carolina region. However, the peanut industry in the Virginia-Carolina region is designed for virginia market-type peanut used for the in-shell market, and popularity of growing runner market-type peanut in this region will most likely depend upon market pressures rather than agronomic potential.

Z-pinches, created using the Z accelerator, generate ∼220 TW, 1.7 MJ radiation pulses that can heat large (∼103 cm) hohlraums to 100–150 eV temperatures for times of order 10 ns. We are performing experiments exploiting this intense radiation to drive shock waves for equation of state studies. The shock pressures are typically 1–10 Mbar with 10 ns duration in 6-mm-diameter samples. We demonstrate the ability to perform optical spectroscopy measurements on shocked samples located in close proximity to the z-pinch. These experiments are particularly well suited to optical spectroscopy because of the relatively large sample size and long duration. The optical emission is collected using fiber optics and recorded with a streaked spectrograph. Other diagnostics include VISAR and active shock breakout measurements of the shocked sample and a suite of diagnostics that characterize the radiation drive. Our near term goal is to use the spectral emission to obtain the temperature of the shocked material. Longer term objectives include the examination of deviations of the spectrum from blackbody, line emission from lower density regions, determination of kinetic processes in molecular systems, evaluation of phase transitions such as the onset of metallization in transparent materials, and characterization of the plasma formed when the shock exits the rear surface. An initial set of data illustrating both the potential and the challenge of these measurements is described.

Reducing costs associated with pest management in peanut (Arachis hypogaea L.) production systems in the United States will become increasingly important due to changes in federal legislation that reduced support prices and removed the escalator provision. The federal peanut program may be eliminated completely in 2002 at which time peanut most likely will be marketed at the world price, which is substantially lower than the current quota price. Eight experiments were conducted during 1997 and 1998 to evaluate pest control, pod yield, gross value, and economic return with preventive and integrated pest management (IPM)-based disease, insect, and weed management strategies. Preventive strategies included prophylactic applications of herbicides, fungicides, fumigant, and insecticides. IPM strategies involved host-plant resistance, targeting pesticide applications based on economic thresholds, and other thresholdbased practices to manage pests. Preventive and IPM weed management strategies provided similar economic return in seven of eight experiments. Early leaf spot, caused by Cercospora arachidicola, control was similar when fungicides were applied biweekly or based on weather advisories. However, scheduling fungicide sprays using weather-based advisories eliminated one to three fungicide applications per year. Biweekly applications of fungicides increased damage from twospotted spider mite (Tetranycychus urticae) in one experiment compared with applications using weather-based advisories. Fumigation by metam sodium for Cylindrocladium black rot (CBR), caused by Cylindrocladium crotalarie, was needed in one of three experiments where this disease was present. Resistance of the cultivar NC 12C to CBR was not sufficient to prevent yield and economic loss where damage exceeded 10% plant loss. Iprodione was applied preventatively for suppression of Sclerotinia blight, caused by Sclerotinia minor. However, this disease developed in only one of four experiments where fungicide was applied. Aldicarb applied infurrow and acephate applied postemergence based on damage thresholds controlled tobacco thrips (Frankliniella fusca) similarly in seven of eight experiments. In one experiment, aldicarb was more effective than acephate. Failure to apply chlorpyrifos for southern corn rootworm (Diabrotica undecimpunctata) control resulted in yield and economic loss in three experiments. Chlorpyrifos controlled potato leafhopper (Empoasca fabae) and prevented possible yield loss caused by this insect. Collectively, these data demonstrate the complexity of pest management in peanut and some of the weaknesses associated with current pest control and IPM practices. The importance of accurate identification of pests and detailed field histories also was demonstrated in these studies. Likewise, a thorough understanding of the impact of production practices on pest development and timely implementation of pest control tactics is critical for adequate plant protection.

Epidemiological information can be used with weather data to anticipate disease onset. These disease advisories can be applied to reduce the unnecessary use and improve the timing of fungicide sprays. Delivery of weather-based disease advisories to peanut growers in North Carolina was expedited by streamlining programming and information deployment procedures. This approach utilized a standard method of organization of weather data collection and analysis for all diseases, and daily reports were posted to the web. A standardized method of analysis is described which is flexible, and it allows information from epidemiological studies and practical experiences to be integrated to create a specific model for individual diseases. Included is a description of the research and extension activities over a 17-yr period during which weather-monitoring hardware and disease advisories were developed, tested, and utilized for advisories in peanuts at the farm level. Advantages and limitations to this approach with reference to its use in other crops are discussed.

Sclerotinia blight of peanut, incited by Sclerotinia minor, causes serious losses when cool, moist conditions prevail in the plant canopy. The effects of altering canopy structure by pruning were investigated in this study. Disease incidence was used to calculate area under the disease progress curve (AUDPC) for field plots receiving various shoot-pruning treatments. In 1990, pruned plots and iprodione-sprayed plots did not differ in AUDPC, but pruned plots produced higher yields. Disease levels and yield of July top-pruned plants did not differ from those of August top-pruned plants. Pruning tops and sides in August reduced yields compared to pruning tops and sides in July, even though August pruning produced lower AUDPC. Without fungicide treatment, the 1991 pruned plots had less disease than nonpruned plots, although yields did not differ significantly. Pruned plots treated with fungicides for control of Sclerotinia blight had less disease than nonpruned plots treated with these fungicides, but there were no differences in yield. Pruning peanut canopies to alter microclimate or enhance fungicide penetration may reduce disease and increase yield when S. minor damage is yield limiting.

Two fluorometric assays for the determination of poly-β-hydroxybutyrate (PHB) inside intact cells are presented in this paper, a spectrofluorometric method and one based on a laser flow cytometer. The principles of these assays are given, and the results of these methods are compared with those of a gas chromatographic assay. All assays were used for the monitoring of batch cultivations of Alcaligenes eutrophus. The correlation between all methods was very good; however, the fluorometric analysis was the fastest while the cytometric assay gave a direct insight into the PHB distribution over the population.

Google Earth tours (GETs) are recorded fl ights around Google Earth. They are highly engaging to watch and have great potential for communicating spatially in a teaching environment. They also benefi t from being easy for an educator to produce but they can be ineffective if they are designed poorly. With this in mind, in this paper we cover three main topics: (1) we consider how best to produce GETs, (2) we deconstruct them as a communication media and fi nally (3), we consider the larger educational context in which they are used. By reviewing literature relevant to these areas we produce 19 best practices for using GETs in education. The amount of evidence we can show in support of our best practices varies. Those that were generated by comparing GETs to the well-researched area of educational animations are highly reliable because they are based on empirical evidence. Those associated with the virtual fl ights between locations within a GET are more open to interpretation as they have been less well studied. We conclude that further work should be focused on investigating virtual flight within a GET