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Detailed information about landslide occurrence is the foundation for advancing process understanding, susceptibility mapping, and risk reduction. Despite the recent revolution in digital elevation data and remote sensing technologies, landslide mapping remains resource intensive. Consequently, a modern, comprehensive map of landslide occurrence across the United States (USA) has not been compiled. As a first step toward this goal, we present a national-scale compilation of existing, publicly available landslide inventories. This geodatabase can be downloaded in its entirety or viewed through an online, searchable map, with parsimonious attributes and direct links to the contributing sources with additional details. The mapped spatial pattern and concentration of landslides are consistent with prior characterization of susceptibility within the conterminous USA, with some notable exceptions on the West Coast. Although the database is evolving and known to be incomplete in many regions, it confirms that landslides do occur across the country, thus highlighting the importance of our national-scale assessment. The map illustrates regions where high-quality mapping has occurred and, in contrast, where additional resources could improve confidence in landslide characterization. For example, borders between states and other jurisdictions are quite apparent, indicating the variation in approaches to data collection by different agencies and disparity between the resources dedicated to landslide characterization. Further investigations are needed to better assess susceptibility and to determine whether regions with high relief and steep topography, but without mapped landslides, require further landslide inventory mapping. Overall, this map provides a new resource for accessing information about known landslides across the USA.

International audience

Despite sizeable short-term effects of neurofeedback (NF) therapy on attention-deficit and hyperactivity disorder (ADHD), longer-term clinical, comorbidity and self-regulation outcomes are less systematically studied. The aim of this largest NF follow-up to date was to evaluate these outcomes 6 months after NF compared to a semi-active control to disentangle specific from unspecific sustained effects. We performed a multicenter, randomized, parallel, controlled, clinical, superiority trial in five German university outpatient departments. Participants were eligible if they fulfilled DSM-IV-TR criteria for ADHD and were aged from 7 to 9 years. Participants were randomly assigned (1:1-ratio) to 25 sessions of slow cortical potential (SCP)-NF or electromyogram biofeedback (EMG-BF). Participants were not blinded, since they received instructions according to each treatment setting. Primary outcomes were parent ratings of ADHD. The trial was registered, number ISRCTN761871859. Both groups showed improvement of ADHD symptoms compared to baseline at 6-months follow-up with large effect sizes for SCP-NF (d = 1.04) and EMG-BF (d = 0.85), but without group differences. When analyzing all assessments (pre-test, post-test-1, post-test-2 and follow-up), a group-by-time interaction emerged (p = 0.0062), with SCP-NF showing stable improvement following treatment but EMG-BF showing a relapse from post-test-1 to post-test-2, and subsequent remission at follow-up. Six months after the end of treatment, improvement after SCP-NF remained large and stable. However, the lack of group differences at follow-up suggests shared specific and unspecific effects contributing to this clinical outcome. Our correlational results indicate specificity of SCP-NF for selected subscales after training, but not at follow-up.

International audience; Abstract Coastal flooding due to surge events represents natural hazards with huge potential consequences for coastal regions. Sea level time series display variations on a large range of timescales, with a deterministic component associated with tidal variations and a stochastic component primarily associated with meteorological forcing, the non-tidal residual. The deterministic component can be evaluated using a model taking into account astronomical forcing and topographic information. The measured sea level is the sum of a slowly varying mean sea level component, the tidal term and the stochastic term. Here, we consider hourly time series recorded in the ports of Boulogne-sur-Mer, Calais, and Dunkirk, in the eastern English Channel. Measured data and modeled data, both provided by the SHOM (“Service hydrographique et océanographique de la marine,” hydrographic and oceanographic services of the French Navy), are analyzed using Fourier spectral analysis. The statistics of return times of extreme events are also estimated directly from the time series and compared between modeled and measured data. It is found that return times from tidal or measured time series are quite different for large thresholds and that they also have a very different Fourier power spectrum, the measured data having a power-law regime which is not found in the modeled tidal data. It is also shown, using Hilbert–Huang transform, that non-tidal residual time series are intermittent and possess multifractal scaling properties. Finally, water level non-tidal residual relationship is explored, and it is shown that the larger mean values of the surge (negative and positive parts) are obtained for the medium level of the tidal value.

In Huascaran National Park (HNP), Peru, grazing and anthropogenic burning have been interacting for decades with natural ignitions and climate variability to reconfigure the fire regimes of the vegetative communities. However, over the last few decades, human alterations to the region’s fire regime were perceived by resource managers to have led to an overall increase in fire occurrence and fire extent. Resource managers are now very concerned about the impacts of increasing anthropogenic fires in the National Park because these fires seem to disrupt ecological processes and tourism. To test these beliefs and examine the fire activity from 2002 to 2014, we used a time series of several different data products including the MODIS Terra and Aqua platforms (Active Fire and Burned Area) as well as local air temperature and precipitation data. The intra-annual distribution of fires in the HNP and its buffer zone (BZ) showed a consistent increase in the number of active fires and burned areas during the dry season (Peruvian winter). The active fire anomalies showed higher fire activity in the HNP over the period 2002 to 2014. However, burned area anomalies showed consistently higher fire activity in the BZ during the high fire years in 2003, 2005, 2010, and 2014. The spatial distribution of areas burned in the HNP and the BZ from 2002 to 2014 showed that most recurrent burning was inside the BZ, which is in compliance with the HNP’s policy but in contradiction with local resource managers’ perceptions. Although human activity may influence local fire dynamics, fire responses seemed to be mainly influenced by local climate oscillations. Our results suggest a clear fire response to local climate and, in particular, to precipitation variability. However, it appears that there was a low fire return interval for any given location and that the total area burned for a given year is relatively small. Therefore, small-scale fires created an appearance of larger fire impacts than actually occur within the HNP and its BZ. In this instance, fire perception and fire reality are not aligning and the new challenge for resource managers is how best to reconcile these two factors to more effectively manage the parklands.

Turbulent characteristics in the atmospheric surface layer are investigated using a data-driven method, Hilbert spectral analysis. The results from empirical mode decomposition display a set of intrinsic mode functions whose characteristic scales suggest a dyadic filter-bank property. It can be concluded from the joint probability density function of the intrinsic mode functions that the turbulent properties are totally different under different stratifications: the amplitudes (or energies) are arranged according to the stability parameter for stable conditions, but tend to cluster randomly for unstable cases. The intermittency analyses reveal that second-order Hilbert marginal spectra display a power-law behaviour in the inertial subrange, and that the scaling exponent functions deviate from the theoretical values due to the strong intermittency in the stable boundary layer.

To develop a simple approach to increase titers of transient gene expression in CHO cells without relying on host cell line engineering as recent reports suggest that for PEI-mediated transfections, under optimized conditions, DNA delivery into cells and nuclei is not the limiting factor. N, N-Dimethyl acetamide (DMA) was utilized to enhance transcription. To target post-transcriptional events, we evaluated the co-expression of various genes involved in the unfolded protein response, namely XBP1S, ATF4, CHOP and HSPA5. XBP1S overexpression led to a 15–85 % increase in titer for multiple therapeutic proteins. Mechanistic studies confirmed that addition of 0.125 % DMA increased transgene mRNA levels as expected. However, overexpression of XBP1S had no effect on transgene mRNA levels, indicating that it influenced post-transcriptional events. Since DMA and XBP1S targeted different pathways, the combination of the two approaches led to an additive improvement in protein titer (150–250 % titer increase). Transcriptional and post-transcriptional pathways of transient gene expression can be targeted to increase titers without resorting to host cell line engineering in a simple, short, 7 day production process.

This study is the first in situ work comparing rapid light curves (RLC) and non-sequential steady-state light curves (N-SSLC) in their efficiency to characterize phytoplankton photosynthetic activity and acclimation status. Measurements were carried out at two time scales (daily and annual) using the Pulse Amplitude Modulated fluorometry on samples taken in the coastal waters of a macrotidal ecosystem (the Strait of Dover, eastern English Channel). RLC and N-SSLC were compared under a wide range of environmental conditions and phytoplankton composition in order to define the best methodology to accurately capture short and long-term adjustments in the functioning of the photosynthetic apparatus. The relationships between the photosynthetic parameters extracted from RLC and N-SSLC were also studied to evaluate the possibility to use RLC to predict N-SSLC photosynthetic parameters and thus obtaining the acclimation status at steady state. At daily scale, the maximum electron transport rate and light saturation coefficient resulting from RLC (respectively, ETRm_RLC and E k_RLC) were found to follow more closely short-term environmental light variations than ETRm and E k resulting from N-SSLC (ETRm_N-SSLC and E k_N-SSLC) did. RLC were thus able to detect rapid changes in photosynthetic activity that would have been overlooked with N-SSLC measurements. At annual scale, few differences were found between RLC and N-SSLC. Variations of ETRm and α derived from RLC and N-SSLC were very similar but absolute values were lower for RLC measurements. Because, at daily scale, RLC better capture the short-term changes in photosynthetic activity than N-SSLC do, using RLC to predict N-SSLC photosynthetic parameters and getting information about steady-state acclimation status is not possible at this time scale. However, this can be done at seasonal scale.

One of the most serious tuber quality concerns of US chip potato growers is stem-end chip defect, which is defined as a localized post-fry discoloration in and adjacent to the vasculature on the stem end portion of potato chips. The severity and incidence of stem-end chip defect vary with growing location and variety, but quantitative data describing this are not available. A multi-year and location study was conducted to evaluate chipping potato varieties for tolerance to stem-end chip defect formation and to quantify defect severity and incidence regionally and temporally. It was observed that higher night temperature in July and August compared to the regional 30-year history was consistently associated with higher SECD severity. Average SECD severity was linearly correlated with incidence of chips having severe SECD. Chip color and tuber stem-end glucose content were significantly correlated with average SECD score across all treatments. Multiple tuber samplings from early growing season to mid post-harvest storage demonstrated that some varieties, such as Nicolet and Pike, had fewer stem-end chip defects than other varieties across years and locations. Stem-end chip defect was rarely observed prior to harvest, but was apparent at the time of harvest on multiple varieties depending on the year and location. Tuber stem-end sucrose and glucose prior to harvest were not indicators of defect development at harvest and out of storage, but pre-harvest chip color was significantly correlated with defect severity 10 weeks after preconditioning was finished.

An environmental and technical sustainability assessment methodology is developed for both centralized and dual water distribution systems (WDSs) with and without fire flow scenarios. Technical sustainability of potable and reclaimed water networks is measured by a sustainability index (SI) assessment using reliability, resiliency, and vulnerability performance criteria. The U.S. Environmental Protection Agency EPANET software is used to simulate hydraulic (i.e. nodal pressure) and water quality (i.e. water age) analysis in a WDS. Total fresh water use and total energy intensity are considered as environmental sustainability criteria. The procedure considers two separate alternatives for meeting fire flows: (1) adding pumping to a system or (2) adding a non-potable WDS. The reclaimed system is designed using linear programming (LP) optimization. For each alternative, multi-criteria decision analysis (MCDA) is used to combine technical and environmental sustainability criteria for an urban WDS.

A methodology is presented for determining sustainability indices for pressure and water age in water distribution systems (WDSs). These sustainability indices are based upon performance criteria including reliability, resiliency, and vulnerability. Pressure and water age are determined for a WDS as a function of operation time using the U.S. Environmental Protection Agency EPANET model. The values of pressure and water age are used to determine reliability, resiliency, and vulnerability performance criteria, which are then combined into the nodal sustainability indices for water age and pressure. In addition, the sustainability index (SI) computations are performed for zones to define the SI for water age and SI for pressure. A combined SI calculation is performed to produce an overall sustainability score for the entire zone in the water distribution network. The proposed methodology can be used to monitor the sustainability of existing WDSs and to help define alternative solutions including changes in pump operation and modifications to WDS to increase the sustainability.

An ice microphysics parameterization scheme has been modified to better describe and understand ice fog formation. The modeling effort is based on observations in the Sub-Arctic Region of Interior Alaska, where ice fog occurs frequently during the cold season due to abundant water vapor sources and strong inversions existing near the surface at extremely low air temperatures. The microphysical characteristics of ice fog are different from those of other ice clouds, implying that the microphysical processes of ice should be changed in order to generate ice fog particles. Ice fog microphysical characteristics were derived with the NCAR Video Ice Particle Sampler during strong ice fog cases in the vicinity of Fairbanks, Alaska, in January and February 2012. To improve the prediction of ice fog in the Weather Research and Forecasting model, observational data were used to change particle size distribution properties and gravitational settling rates, as well as to implement a homogeneous freezing process. The newly implemented homogeneous freezing process compliments the existing heterogeneous freezing scheme and generates a higher number concentration of ice crystals than the original Thompson scheme. The size distribution of ice crystals is changed into a Gamma distribution with the shape factor of 2.0, using the observed size distribution. Furthermore, gravitational settling rates are reduced for the ice crystals since the crystals in ice fog do not precipitate in a similar manner when compared to the ice crystals of cirrus clouds. The slow terminal velocity plays a role in increasing the time scale for the ice crystals to settle to the surface. Sensitivity tests contribute to understanding the effects of water vapor emissions as an anthropogenic source on the formation of ice fog.

Empirical frequency distributions of multiplicative cascade weights, or breakdown coefficients, at small timescales are analyzed for 5-min precipitation time series from four gauges in Germany. It is shown that histograms of the weights, W, are strongly deformed by the recording precision of rainfall amounts. A randomization procedure is proposed to statistically remove the artifacts due to precision errors in the original series. Evolution of the probability distributions of W from beta-like for large timescales to combined beta-normal distribution with a pronounced peak at W ≈ 0.5 for small timescales is observed. A new 3N-B distribution built from 3 separate normal, N, distributions and one beta, B, distribution is proposed for reproduction of the empirical histograms of W at small timescales. Parameters of the 3N-B distributions are fitted for all gauges and analyzed timescales. Microcanonical cascades models with a generator based on 3N-B distributions are developed and their performance at disaggregating precipitation at 1280-min intervals down to 5-min intervals is evaluated.

Behavioural observations of male copepods revealed that they commonly follow female footprints to find their mates. Copepods can perceive signals generated by females either hydromechanically or chemically. Signal intensity is affected by hydrodynamic conditions which clear chemical and mechanical cues and modulate copepod’s ability to sense signals of their biotic environment, such as in their search for mates. We studied the patterns and efficiency of the copepod Pseudodiaptomus annandalei to mate in calm and hydrodynamically disturbed waters, in illuminated and dark conditions in experimental containers of different shapes and volumes. Courtship in P. annandalei was a negative function of hydromechanical disturbance, since successful mating events were observed in calm water only. In weakly turbulent conditions (air-bubbling of 100 ml/min), males were not able to pursue females properly; swimming speed decreased about three times in comparison with that in calm water. In calm water conditions, sequential and simultaneous taxis mechanisms were used by P. annandalei males to pursue females. The ability of P. annandalei males to track a three-dimensional trail probably depended on the persistence of fluid-borne signals.

International audience; Studies on the behavior of copepods require both an appropriate experimental design and the means to perform objectively verifiable numerical analysis. Despite the growing number of publications on copepod behavior, it has been difficult to compare these studies. In this study, we studied two species of copepods, Eurytemora affinis and Pseudodiaptomus annandalei, and employed recently developed scaling and non-scaling methodology to investigate the effects of density and volume on the swimming behavior of individual organisms in still water. We also compared the results of two- and three-dimensional projections of the swimming tracks. A combination of scale-dependent and scale-independent analysis was found to characterize a number of behavioral observations very effectively. We discovered that (i) density has no effect except to increase the time spent in the swimming state of "breaking", (ii) smaller volumes resulted in more complex trajectories, and larger volumes, like density, increased the time spent in the swimming state "breaking", and (iii) three-dimensional projections gave a more accurate estimation of speed and the time spent cruising. When only a vertical 2D projection was used, "cruising" could be confused with "sinking". These results indicate that both experimental conditions and the selection of 2D or 3D projection have important implications regarding the study of copepod behavior. The development of standardized procedures with which to compare the observations made in different studies is an issue of particular urgency.

In order to enhance encounters with prey, planktonic predators may display different swimming behavior with respect to food availability and distribution. In this study, we used 3D video techniques to record the swimming behavior of malabar grouper (Epinephelus malabaricus) larvae in both the absence and the presence of prey (Artemia sp. nauplii). Swimming properties were investigated in all of the 3D, the two vertical, and the horizontal projections using scale-dependent (mean speed and Net to Gross Displacement Ratio) and scale-independent (fractal dimension) metrics. When prey was added, larvae swam slower and in a less convoluted way as compared to what was observed in the absence of food. The results obtained with scale-dependant metrics were confirmed by those obtained with scale-independent analyses. Both unveiled the anisotropy of the swimming behavior of grouper larvae that tend to swim toward the vertical axis in order to maximize encounters with prey patches. This study shows that malabar grouper larvae can optimize their search volume by switching their behavior and further draws attention to the need to consider both vertical- and horizontal-projections components while addressing the plankter’s swimming trajectories.

Background and purpose By virtue of their high linear energy transfer (LET) characteristics the biologic effectiveness of neutrons is less dependent on tissue oxygenation tension and cell cycle phase as compared to that with photons. Hence, an improved clinical benefit is to be expected predominantly in large, hypoxic and slowly growing tumors. Since a short course of radiotherapy is required for clinical reasons, it prompted the authors to initiate a randomly controlled trial on locally advanced breast cancer. Patients and methods Between 1996 and 1999, 27 patients with locally advanced breast cancer were irradiated with photons (60 Gy, 30 fractions; 8 MV, (60)Co) or neutrons (18 Gy, twelve fractions; 66 MeV(p-->Be)). The mean tumor diameters were 699 +/- 399 ml for the photon group and 1,097 +/- 831 ml in the neutron group. Results After a mean follow-up period of 21.5 months tumor involution was evaluated in 22 patients. Partial and complete remissions were registered in 6/10 patients of the photon group and 5/12 patients of the neutron group. Late grade 3-4 morbidity according to RTOG definition was scored in 5/10 patients in the photon group and in 6/12 patients in the neutron group. With regard to tumor control and late radiation morbidity no differences between the two treatment arms were observed. Conclusion The underlying data indicate that no benefit is to be expected from neutron therapy in breast cancer.

Ewing's tumors are sensitive to radio- and chemotherapy. Patients with multifocal disease suffer a poor prognosis. Patients presenting primary bone marrow involvement or bone metastases at diagnosis herald a 3-year disease-free survival below 15%. The European Intergroup Cooperative Ewing's Sarcoma Study (EICESS) has established the following indications for high-dose therapy in advanced Ewing's tumors: Patients with primary multifocal bone disease, patients with early (

Potatoes (Solanum tuberosum) in Wisconsin are predominately grown on soils that have a high potential for agrichemical leaching. Weed control strategies are not designed for season long control from a single high rate herbicide application but for reduced rates combined with mechanical and cultural strategies. The current recommended herbicide rates provide 7–9 weeks of efficacy. Mechanical measures provide effective early season control, but development of crop canopy prevents cultivation after about four weeks. Past studies have shown that shade levels comparable to those in a potato canopy can significantly reduce weed biomass. This study was initiated to develop a canopy development model and evaluate the difference between Superior and Russet Burbank potatoes. Plots were established in 1988–1992 at the Hancock Agricultural Research Station on Plainfield loamy sand (mixed, typic Upsidaments). Light readings were taken both under the crop canopy and in full sunlight to determine the amount of shading provided by the crop. Physiological Degree Days (P-days) were used to monitor the development of the potato varieties. Regression analysis was used to determine if P-days could be used as a predictor for canopy development. Superior reached maximum canopy (88% shade) at seven weeks after emergence (WAE) and maintained it until 9 WAE. Russet Burbank reaches maximum canopy at 8 WAE (98% shade) and maintains shading above 80% until 13 WAE. The canopy model is an empirical relationship estimated using regression techniques, and is currently being utilized in a weed management module for the WISDOM © software program.

The cooperativity of the thermal spin transition in the Fe(II) spincrossover compound [Fe(ptz)6](BF4)2 (ptz = 1-propyltetrazole) and in isomorphous mixed crystals with the isostructural zinc complex is investigated. From powder X-ray measurements the lattice deformation (tensor e) accompanying the spin transition is determined. For diluted mixed crystals with x 0.44 a first order crystallographic phase transition (R3i → P1i) is observed on cooling, which is triggered by the spin transition and can be suppressed by cooling rapidly. The thermal spin transition is measured with UV/VIS optical absorption spectroscopy on mixed single crystals in the R3i structure. From this metal dilution experiment an interaction constant of 169 cm − 1 for the cooperativity of the spin transition is determined. Furtheron, this interaction constant is calculated on the grounds of elasticity theory: The lattice deformation due to the spin transition is traced back to anisotropic elastic point defects, which directly interact with each other via their stress fields and indirectly via the surface of the elastic crystal by an image pressure. The elastic properties of the crystalline matrix are taken in the isotropic approximation. They are derived from the complete sets of anisotropic elastic constants of the pure iron and zinc compounds, which have been measured previously by Brillouin spectroscopy. The contribution of elastic energy calculated this way is ≃ 80% of the experimental value of the interaction constant, i.e. the cooperativity in crystalline spincrossover compounds is quantitatively of elastic nature.

Studien mit bildgebenden Verfahren legen eine kortikale Beteiligung am Schmerzerleben nahe. Dennoch kommt es offenbar bei diskreter kortikaler Reizung nicht zur Auslosung von Schmerz. Es wird eine These uber die Konstituierung bewuster Erlebnisse vorgeschlagen, die diesen Widerspruch auflost. Danach wird mentales Geschehen unter Beteiligung von 2 temporalen Prozessen aufgebaut: zum einen werden mit Hilfe neuronaler Oszillationen Systemzustande im 40-Hz-Bereich definiert, innerhalb derer Bindungsoperationen ablaufen, die raumlich verteilte Aktivitaten aufeinander beziehen; zum anderen werden aufeinanderfolgende Systemzustande automatisch bis zu etwa 3 s miteinander verkettet. Greift man in diese neuronalen Programme ein, kann es zu Analgesie und Anasthesie kommen. Reizt man lokal und zeitlich begrenzt, wird nur eine Teilmenge jener neuronalen Strukturen aktiviert, die fur das bewuste Schmerzerleben notwendige Grundlagen sind. Simuliert man in der Reizsituation das raumlich-zeitliche Muster neuronaler Aktivitaten, wie es sich in ersten PET-Studien zeigte, wird vorausgesagt, das Schmerzerleben ausgelost wird.

The Lamb-Mossbauer factor in spin crossover compounds has been the subject of controversial discussions in the literature. For several compounds, a significantly larger Lamb-Mossbauer factor for the complex molecules in the low-spin (fls) than in the high-spin (fhs) state has been reported, while for compounds studied in our laboratory such differences could not be observed. We prepared the compound Fe(tpa)(NCS)2, thef factors of which were reported to be very different. We could not prove thef factors of this compound to be different. The implications of a different structural phase of compound prepared by us are discussed.

The 200 MeV cyclotron facility at the National Accelerator Centre has been operational since 1987. Between September 1988 and December 1997 a total of 973 patients (26,916 fields) had been treated on the 66 MeV p+Be isocentric neutron therapy system. Patients are currently being treated according to several protocols, including tumors of the head and neck, salivary gland and breast and soft tissue sarcomas, uterine sarcomas and paranasal sinuses. A multiblade post-collimator trimmer has recently being installed. This device provides improved neutron beam shaping capability. Between September 1993 and December 1997 a total of 243 patients (4008 fields) had been treated (mainly intracranial stereotactic irradiations) on the fixed horizontal 200 MeV proton therapy facility. The facility incorporates an innovative automatic patient positioning system. Two new fixed beam lines for proton therapy are presently being designed (horizontal and 30 degrees to the vertical) for an existing unused treatment vault. Spot scanning systems will be developed for both beam lines.

Morphine and codeine were isolated from blood with C18 Bond Elut columns and derivatised with pentafluoropropionic anhydride (PFPA). The PFPA-derivatives were examined by means of gas chromatography/mass spectrometry using electron impact and chemical ionisation (positive and negative mode). The negative chemical ionisation, as most sensitive, was applied for the quantitation of both examined substances in forensic blood samples.

In holographic Bragg gratings formed by anisotropic photopolymerization of free-radical monomers, an electric field is required to switch the grating between a diffracting and a transmitting state. The voltage necessary to turn the grating completely off is defined as the switching voltage. In this work, we report on the gradual increase of this switching voltage with time after initial fabrication. The switching field increases approximately 60% over a seven-day period for a pentaacrylate/E7 material system. Using dielectric measurements, it is observed that the resistance of the cell does not change over time while the capacitance decreases. FT-IR spectroscopy was also used to explore the continued post-polymerization after fabrication of the gratings. Increases in switching field were observed for samples fully illuminated with light as well as those kept in the dark. We speculate that the rise in the switching voltage is caused by post polymerization of residual reactive moieties located near the polymer/nematic droplet interface. An increase in the amount of interfacial area generated by post-polymerization yields more surface area for the LC molecules to bind; thus a larger field is needed to switch.

Results on the nonlinear properties of solutions of Buckminsterfullerene in toluene are reported. Optical limiting thresholds are as low as 15 mJ/cm2 with multiple pulse stability. Evidence for a different mechanism than that applicable in graphitic carbon black suspensions is presented. The calculated second hyperpolarizability agrees with experimentally reported values.

TEL-AML1 positivity in relapsed B cell precursor acute lymphoblastic leukemia in childhood

Studies were conducted to evaluate the efficacy of scopolamine, absorbed through intact skin, in preventing motion sickness at sea. Efficacy of transdermal scopolamine was compared with oral dimenhydrinate and placebo. Transdermal applications were made 4 to 16 hr before exposure to motion. Dimenhydrinate or placebo was given 1.5 hr before motion and again 2.5 hr after motion began. Comparison with placebo indicated that transdermal scopolamine provided protection against motion sickness at a significance level of p = 0.0001 and oral diphenhydrinate at a level of p = 0.05. Dry mouth, drowsiness, and blurred vision associated with transdermal scopolamine therapy were minimal. Clinical Pharmacology and Therapeutics (1981) 29, 414–419; doi:10.1038/clpt.1981.57

Les ionenes de formule {[NMe2(CH2)5NMe2(CH2)n]2I}p (avec Me=radical methyl;n=3, 4, 5; etp le degre de polymerization) ont ete prepares. Leur spectre RMN et IR est presente et discute. Associes a de l'iodure d'argent, ils donnent des composes conducteurs qui suivent la loi d'Arrhenius. Le systeme AgI-polydiiodure de N pentylene N′ propylene tetramethyl N, N, N′, N′ diammonium possede a 25°C une conductivite maximale de 0.01 Ω cm−1 pour une composition renfermant 80% en equivalent de AgI. Cette etude se place dans une perspective de mise au point de generateurs tout solide.

The overall frequency and types of complications associated with diagnostic coloscopy and coloscopic polypectomy are unknown. A statewide survey of coloscopists was conducted to determine the morbidity and mortality associated with coloscopy. Twenty-eight physicians performed a total of 1,106 coloscopic procedures. 9 colonic perforations and 5 episodes of colonic bleeding resulted in a 1.3% complication rate. Explanations for several of the complications are identified and preventive measures proposed. 1 patient died of an unrecognized perforation of the sigmoid colon, resulting in a 0.09% mortality rate. Of 14 complications reported in this series, 12 occurred during the early experience (less that 40 procedures) of the coloscopist. Training programs in coloscopy need to be established in order to reduce the morbidity and mortality associated with a physician's early coloscopic experience.