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This study aimed establish the variations in the phytotoxic activity of hexane, ethyl acetate and methanol extracts of Moutabea guianensis, and methyl caffeate and scopoletin isolated from the ethyl acetate extract, variyng the concentration and the receptor species. Phytotoxic activity bioassays of germination (at 25 °C and 12 hours of photoperiod) and development of radicle and hypocotyl (25 °C and 24 hours of photoperiod) were developed. The seed germination of Mimosa pudica was sensitive to the roots hexane, ethyl acetate and methanol extracts at 1% (w/v), with inhibition potentials in 92%, 100% and 100%, respectively. Comparative analysis on the phytotoxic activity of the tested compounds revealed that scopoletin showed a higher inhibition potential on the seed germination bioassay against Mimosa pudica. Senna obtusifolia was not sensitive to the tested compounds. Methyl caffeate showed the highest potential to inhibit the development of radicle and hypocotyls, and the intensity of the allelopathic effects varied with the concentrations.

Aumento da demanda mundial por combustíveis líquidos, aquecimento global, segurança e estabilidade energética, vontade política por desenvolvimento nos campos da agricultura, social e energético são pontos que mostram a necessidade do desenvolvimento de novas tecnologias para a produção do biodiesel, a partir de diversas culturas agrícolas espalhadas por todos os países bem como a busca dos aditivos que melhorem sua estabilidade e estocagem. Diante deste cenário, o objetivo deste estudo foi investigar o comportamento oxidativo do biodiesel de soja puro e com adição de antioxidantes sob condições de estocagem ao relento, avaliando as propriedades físicas, químicas, fluidodinâmicas, teor de água e suscetibilidade à oxidação do biodiesel comercial. O biodiesel de soja metílico foi obtido na sua forma comercial (com adição de antioxidante, BSA100 - TBHQ) e na sua forma pura (sem adição de antioxidante, BS100) e puro – com adição de antioxidantes naturais, BSM50 - 50% de biodiesel de soja puro e 50% de biodiesel de macaúba puro, BS100-13 e BS100-14 - aditivo de extrato de uva Syrah e Petit Verdot –, respectivamente. A Cromatografia gasosa identificou o biodiesel metílico de soja, verificando a existência de 50,41%, referente à linolenato de metila que influencia sensivelmente em sua susceptibilidade no processo de oxidação. As caracterizações físicas e químicas foram realizadas, determinando-se alguns parâmetros: índice de acidez, massa específica e viscosidade cinemática, demonstrando valores dentro do limite permitido, conforme Resolução ANP no 14/2012. Com o aumento do tempo de armazenamento, ocorreu um expressivo aumento do teor de água nos biodieseis bem superior ao limite (350 ppm). Os aditivos produziram pequenos acréscimos no valor da estabilidade à oxidação. Após 30 dias de armazenamento em frascos de aço-carbono, os biodieseis metílicos de soja não mais atenderão à regulamentação da ANP.

The aim of this study was to evaluate the effect of two sowing densities and levels of NPK (02-24- 12) on the production components of the JLM 08 strain of vegetable soybean, in the Savannah of Boa Vista, in the state of Roraima, Brazil. The experiment was carried out from November 2013 to March 2014 in the experimental area of the Centre for Agrarian Sciences at the Cauamé Campus of the Federal University of Roraima in Boa Vista. The experimental design was of randomised blocks in a factorial scheme (2 x 5) with three replications. The two densities (40,000 and 80,000 plants per hectare) comprised the first factor, while five levels of NPK (02-24-12) made up the second (0, 200, 400, 600 and 800 kg ha-1). The following were evaluated: height of insertion of the first and last pod; stem diameter; number of pods per plant having 1, 2, and 3 grains; total number of pods per plant; 100 grain weight and estimated grain yield. The height of insertion of the first and last pod in the JLM 08 genotype of the vegetable soybean is not influenced by the planting densities or levels of formulated fertiliser. At a density of 80,000 plants per hectare, the number of pods per plant is influenced by the levels of fertiliser, demonstrating a positive quadratic response. The level of fertiliser with the maximum technical efficiency (492.86 kg ha-1) gives an 18% increase in grain yield at the highest planting density. = Objetivou-se com este trabalho avaliar o efeito de duas densidades de semeadura e doses de NPK (02-24-12) nos componentes de produção da soja hortaliça linhagem JLM 08, na Savana de Boa Vista, Roraima. O experimento foi conduzido no período de novembro de 2013 a março de 2014, na área experimental do Centro de Ciências Agrária da Universidade Federal de Roraima, Campus Cauamé, em Boa Vista, Roraima. O delineamento experimental adotado foi em blocos ao acaso, em esquema fatorial (2 x 5), com três repetições. O primeiro fator correspondeu a duas densidades (40.000 e 80.000 plantas por hectare), enquanto o segundo a cinco doses de NPK (02-24-12) (0, 200, 400, 600 e 800 kg ha-1). Avaliaram-se a altura de inserção da primeira e da última vagem, diâmetro do caule, número de vagens por planta com 1, 2 e 3 grãos, número de vagens totais por planta, massa de 100 grãos, bem como a estimativa da produtividade de grãos. A altura de inserção da primeira e da última vagem do genótipo de soja-hortaliça JLM 08 não é influenciada pelas densidades de plantio nem pelas doses do adubo formulado. Na densidade de 80.000 plantas por hectare, o número de vagem por planta é influenciado pelas doses do adubo, apresentando resposta quadrática positiva. A dose de máxima eficiência técnica (492,86 kg ha-1) do adubo determina aumento de 18% na produtividade de grãos para a maior densidade de plantio.

O desmódio (Desmodium tortuosum) é uma planta invasora nas lavouras, mas apresenta alto teor de proteína bruta e boa palatabilidade, podendo ser usada na alimentação de ruminantes. No entanto, suas sementes apresentam dormência pela impermeabilidade do tegumento. Assim, objetivou-se com este trabalho avaliar a superação da dormência e influência de diferentes profundidades de semeadura na germinação de sementes de D. tortuosum. Dois experimentos foram realizados em condições controladas, utilizando o delineamento inteiramente casualizados, ambos com cinco tratamentos e seis repetições. No primeiro experimento foram testados cinco modos de quebra de dormência das sementes, e no segundo cinco profundidades de semeadura (0, 1, 2, 4 e 6 cm). A semeadura do segundo experimento ocorreu em bandejas plásticas, utilizando-se como substrato areia lavada e esterilizada em autoclave. Constatou-se que o método mais indicado para a superação da dormência de sementes de D. tortuosum é a escarificação manual com lixa n° 180. A germinação de sementes de D. tortuosum, quando escarificadas manualmente com lixa n° 180, sofre influência direta da profundidade de semeadura, havendo redução drástica com o incremento da profundidade no substrato. A percentagem de germinação das sementes é abruptamente reduzida em profundidade superior a 1,0 cm. A sobrevivência das plântulas aumenta com o aumento da profundidade de semeadura.

Jörg M Steiner, Craig G Ruaux, David A Williams Gastrointestinal Laboratory, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA Abstract: Measurement of serum concentration of pancreatic lipase immunoreactivity (PLI) has been shown to be highly specific for exocrine pancreatic function and sensitive for the diagnosis of canine pancreatitis. Currently, it is recommended that food be withheld for at least 12 hours before collecting a blood sample for analysis from dogs. However, it is unknown whether feeding has any influence on serum canine PLI concentration. Thus, the goal of this study was to evaluate the influence of feeding on serum canine PLI concentrations in healthy dogs. Food was withheld from eight healthy adult Beagle dogs for at least 17 hours and a baseline serum sample (0 minutes) was collected. Dogs were fed and serum samples were collected at 15, 30, 45, 60, 75, 90, 105, 150, 180, 210, 240, 300, 360, 420, and 480 minutes. There was no significant difference in serum canine PLI concentrations at any time after feeding (P=0.131). We conclude that feeding has no significant influence on serum canine PLI concentrations. Keywords: dog, pancreatic function, pancreatitis, biomarker, diagnostic test

Fred Friedberg,1 David A Williams,2 William Collinge31Department of Psychiatry and Behavioral Science, Stony Brook University, Stony Brook, New York; 2Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, 3Collinge and Associates, Kittery, Maine, USAAbstract: Fibromyalgia (FM) is a persistent and disabling widespread pain condition often accompanied by chronic fatigue, cognitive problems, sleep disturbance, depression, anxiety, and headache. To date, the most thoroughly studied non-pharmacological approaches to managing FM are those with a focus on changing patient activities and beliefs that affect the illness. These interventions are intended to facilitate enduring improvement in pain and functional status. Lifestyle-oriented treatments include patient education, aerobic or other physical exercise, and cognitive-behavioral therapy (CBT). These interventions in FM can be delivered in medical or behavioral health care settings by trained professionals, through patient-oriented treatment manuals, or via remote-access technologies. Non-pharmacological treatments, in particular exercise and CBT, have yielded effect sizes and cost–benefit ratios comparable to medications. This paper describes lifestyle-oriented non-pharmacological treatments for FM and highlights selected literature reviews of these interventions. In addition, behavioral and practical issues are addressed that may affect these non-pharmacological treatments, including patient expectations, participant burden, and treatment availability. Recommendations are made to facilitate these interventions and potentially improve outcomes. In particular, the increasing availability of convenient home-based mobile technologies to deliver these non-pharmacological treatments is described.Keywords: cognitive-behavior therapy, exercise, education, mobile technology

Objetivou-se com este trabalho avaliar o efeito de duas densidades e semeadura e doses de NPK (02-24-12) nos componentes de Produção da soja hortaliça linhagem JLM 08, na Savana de Boa Vista, Roraima. O experimento foi conduzido no período de novembro de 2013 a março de 2014, na área experimental do Centro de Ciências Agrária da Universidade Federal de Roraima, Campus Cauamé, em Boa Vista, Roraima. O delineamento experimental adotado foi em blocos ao acaso, em esquema fatorial (2 x 5), com três repetições. O primeiro fator correspondeu a duas densidades (40.000 e 80.000 plantas por hectare), enquanto o segundo a cinco doses de NPK (02-24-12) (0, 200, 400, 600 e 800 kg ha-1). Avaliaram-se a altura de inserção da primeira e da última vagem, diâmetro do caule, número de vagens por planta com 1, 2 e 3 grãos, número de vagens totais por planta, massa de 100 grãos, bem como a estimativa da produtividade de grãos. A altura de inserção da primeira e da última vagem do genótipo de soja-hortaliça JLM 08 não é influenciada pelas densidades de plantio nem pelas doses do adubo formulado. Na densidade de 80.000 plantas por hectare, o número de vagem por planta é influenciado pelas doses do adubo, apresentando resposta quadrática positiva. A dose de máxima eficiência técnica (492,86 kg ha-1) do adubo determina aumento de 18% na produtividade de grãos para a maior densidade de plantio.

Dark matter is a key piece of the current cosmological scenario, with weakly interacting massive particles (WIMPs) a leading dark matter candidate. WIMPs have not been detected in their conventional parameter space (100 GeV ≲M χ ≲ 100 TeV), a mass range accessible with current Imaging Atmospheric Cherenkov Telescopes. As ultraheavy dark matter (UHDM; M χ ≳ 100 TeV) has been suggested as an underexplored alternative to the WIMP paradigm, we search for an indirect dark matter annihilation signal in a higher mass range (up to 30 PeV) with the VERITAS γ-ray observatory. With 216 hr of observations of four dwarf spheroidal galaxies, we perform an unbinned likelihood analysis. We find no evidence of a γ-ray signal from UHDM annihilation above the background fluctuation for any individual dwarf galaxy nor for a joint-fit analysis, and consequently constrain the velocity-weighted annihilation cross section of UHDM for dark matter particle masses between 1 TeV and 30 PeV. We additionally set constraints on the allowed radius of a composite UHDM particle.

Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.

Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.

Asteroids provide fundamental clues to the formation and evolution of planetesimals. Collisional models based on the depletion of the primordial main belt of asteroids predict 10-15 craters >400 km should have formed on Ceres, the largest object between Mars and Jupiter, over the last 4.55 Gyr. Likewise, an extrapolation from the asteroid Vesta would require at least 6-7 such basins. However, Ceres' surface appears devoid of impact craters >∼280 km. Here, we show a significant depletion of cerean craters down to 100-150 km in diameter. The overall scarcity of recognizable large craters is incompatible with collisional models, even in the case of a late implantation of Ceres in the main belt, a possibility raised by the presence of ammoniated phyllosilicates. Our results indicate that a significant population of large craters has been obliterated, implying that long-wavelength topography viscously relaxed or that Ceres experienced protracted widespread resurfacing.

Copyright © 2014 Massachusetts Medical Society. All rights reserved. BACKGROUND In previous clinical trials involving children with X-linked severe combined immunodeficiency (SCID-X1), a Moloney murine leukemia virus-based γ-retrovirus vector expressing interleukin-2 receptor γ-chain (γc) complementary DNA successfully restored immunity in most patients but resulted in vector-induced leukemia through enhancermediated mutagenesis in 25% of patients. We assessed the efficacy and safety of a self-inactivating retrovirus for the treatment of SCID-X1.METHODS We enrolled nine boys with SCID-X1 in parallel trials in Europe and the United States to evaluate treatment with a self-inactivating (SIN) γ-retrovirus vector containing deletions in viral enhancer sequences expressing γc (SIN-γc).RESULTS All patients received bone marrow-derived CD34+ cells transduced with the SIN-γc vector, without preparative conditioning. After 12.1 to 38.7 months of follow-up, eight of the nine children were still alive. One patient died from an overwhelming adenoviral infection before reconstitution with genetically modified T cells. Of the remaining eight patients, seven had recovery of peripheral-blood T cells that were functional and led to resolution of infections. The patients remained healthy thereafter. The kinetics of CD3+ T-cell recovery was not significantly different from that observed in previous trials. Assessment of insertion sites in peripheral blood from patients in the current trial as compared with those in previous trials revealed significantly less clustering of insertion sites within LMO2, MECOM, and other lymphoid proto-oncogenes in our patients.CONCLUSIONS This modified γ-retrovirus vector was found to retain efficacy in the treatment of SCID-X1. The long-term effect of this therapy on leukemogenesis remains unknown.

This paper reports the results from three targeted searches of Milagro TeV sky maps: two extragalactic point source lists and one pulsar source list. The first extragalactic candidate list consists of 709 candidates selected from the Fermi-LAT 2FGL catalog. The second extragalactic candidate list contains 31 candidates selected from the TeVCat source catalog that have been detected by imaging atmospheric Cherenkov telescopes (IACTs). In both extragalactic candidate lists Mkn 421 was the only source detected by Milagro. This paper presents the Milagro TeV flux for Mkn 421 and flux limits for the brighter Fermi-LAT extragalactic sources and for all TeVCat candidates. The pulsar list extends a previously published Milagro targeted search for Galactic sources. With the 32 new gamma-ray pulsars identified in 2FGL, the number of pulsars that are studied by both Fermi-LAT and Milagro is increased to 52. In this sample, we find that the probability of Milagro detecting a TeV emission coincident with a pulsar increases with the GeV flux observed by the Fermi-LAT in the energy range from 0.1 GeV to 100 GeV. © 2014 Elsevier B.V. All rights reserved.

We present deep VERITAS observations of the blazar PKS 1424+240, along with contemporaneous Fermi Large Area Telescope, Swift X-ray Telescope, and Swift UV Optical Telescope data between 2009 February 19 and 2013 June 8. This blazar resides at a redshift of z ≥ 0.6035, displaying a significantly attenuated gamma-ray flux above 100 GeV due to photon absorption via pair-production with the extragalactic background light. We present more than 100 hr of VERITAS observations over three years, a multiwavelength light curve, and the contemporaneous spectral energy distributions. The source shows a higher flux of (2.1 ± 0.3) × 10-7 photons m-2 s -1 above 120 GeV in 2009 and 2011 as compared to the flux measured in 2013, corresponding to (1.02 ± 0.08) × 10-7 photons m-2 s-1 above 120 GeV. The measured differential very high energy (VHE; E ≥ 100 GeV) spectral indices are Γ = 3.8 ± 0.3, 4.3 ± 0.6 and 4.5 ± 0.2 in 2009, 2011, and 2013, respectively. No significant spectral change across the observation epochs is detected. We find no evidence for variability at gamma-ray opacities of greater than τ = 2, where it is postulated that any variability would be small and occur on timescales longer than a year if hadronic cosmic-ray interactions with extragalactic photon fields provide a secondary VHE photon flux. The data cannot rule out such variability due to low statistics. © 2014. The American Astronomical Society. All rights reserved..

TeV-flaring activity with timescales as short as tens of minutes and an orphan TeV flare have been observed from the blazar Markarian 421 (Mrk 421). The TeV emission from Mrk 421 is believed to be produced by leptonic synchrotron self-Compton (SSC) emission. In this scenario, correlations between the X-ray and the TeV fluxes are expected, TeV orphan flares are hardly explained, and the activity (measured as duty cycle) of the source at TeV energies is expected to be equal to or less than that observed in X-rays if only SSC is considered. To estimate the TeV duty cycle of Mrk 421 and to establish limits on its variability at different timescales, we continuously observed Mrk 421 with the Milagro observatory. Mrk 421 was detected by Milagro with a statistical significance of 7.1 standard deviations between 2005 September 21 and 2008 March 15. The observed spectrum is consistent with previous observations by VERITAS. We estimate the duty cycle of Mrk 421 for energies above 1 TeV for different hypotheses of the baseline flux and for different flare selections and we compared our results with the X-ray duty cycle estimated by Resconi et al. The robustness of the results is discussed. © 2014. The American Astronomical Society. All rights reserved..

Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored thenorthern sky during the period February 1997 through May 1998. With a largefield of view and high duty cycle, this instrument was used to perform a searchfor TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54gamma-ray bursts at keV energies were observed by the Burst And TransientSatellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. Thispaper describes the results of a preliminary analysis to search for TeVemission correlated with BATSE detected bursts. Milagrito detected an excess ofevents coincident both spatially and temporally with GRB 970417a, with chanceprobability $2.8 \times 10^{-5}$ within the BATSE error radius. No othersignificant correlations were detected. Since 54 bursts were examined thechance probability of observing an excess with this significance in any ofthese bursts is $1.5 \times 10^{-3}$. The statistical aspects and physicalimplications of this result are discussed.

Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored thenorthern sky during the period February 1997 through May 1998. With a largefield of view and high duty cycle, this instrument was used to perform a searchfor TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54gamma-ray bursts at keV energies were observed by the Burst And TransientSatellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. Thispaper describes the results of a preliminary analysis to search for TeVemission correlated with BATSE detected bursts. Milagrito detected an excess ofevents coincident both spatially and temporally with GRB 970417a, with chanceprobability $2.8 \times 10^{-5}$ within the BATSE error radius. No othersignificant correlations were detected. Since 54 bursts were examined thechance probability of observing an excess with this significance in any ofthese bursts is $1.5 \times 10^{-3}$. The statistical aspects and physicalimplications of this result are discussed.

Previous works have shown that water Cherenkov detectors have superiorsensitivity to those of scintillation counters as applied to detectingextensive air showers (EAS). This is in large part due to their much highersensitivity to EAS photons which are more than five times more numerous thanEAS electrons. Large area water Cherenkov detectors can be constructedrelatively cheaply and operated reliably. A sparse detector array has beendesigned which uses these types of detectors to substantially increase the areaover which the Milagro Gamma Ray Observatory collects EAS information.Improvements to the Milagro detector's performance characteristics andsensitivity derived from this array and preliminary results from a prototypearray currently installed near the Milagro detector will be presented.

The Milagro detector is an air shower array which uses the water Cherenkovtechnique and is capable of continuously monitoring the sky at energies near 1TeV. The detector consists of 20000 metric tons of pure water instrumented with723 photo-multiplier tubes (PMTs). The PMTs are arranged in a two-layerstructure on a lattice of 3 m spacing covering 5000 $m^2$ area. The directionof the shower is determined from the relative timing of the PMT signals,necessitating a common time reference and amplitude slewing corrections toimprove the time resolution. The calibration system to provide these consistsof a pulsed laser driving 30 diffusing light sources deployed in the pond toallow cross-calibration of the PMTs. The system is capable of calibrating timesand the pulse-heights from the PMTs using the time-over-threshold technique.The absolute energy scale is provided using single muons passing through thedetector. The description of the calibration system of the Milagro detector andits prototype Milagrito will be presented.

The Milagro Gamma Ray Observatory is the world's first large-area waterCherenkov detector capable of continuously monitoring the sky at TeV energies.Located in northern New Mexico, Milagro will perform an all sky survey of theNorthern Hemisphere at energies between ~250 GeV and 50 TeV. With a high dutycycle, large detector area (~5000 square meters), and a wide field-of-view (~1sr), Milagro is uniquely capable of searching for transient and DC sources ofhigh-energy gamma-ray emission. Milagro has been operating since February,1999. The current status of the Milagro Observatory and initial results will bediscussed.

Milagrito, a prototype for the Milagro detector, operated for 15 months in1997-8 and collected 8.9 billion events. It was the first extensive air shower(EAS) array sensitive to showers intiated by primaries with energy below 1 TeV.The shadows of the sun and moon observed with cosmic rays can be used to studysystematic pointing shifts and measure the angular resolution of EAS arrays.Below a few TeV, the paths of cosmic rays coming toward the earth are bent bythe helio- and geo-magnetic fields. This is expected to distort and displacethe shadows of the sun and the moon. The moon shadow, offset from the nominal(undeflected) position, has been observed with high statistical significance inMilagrito. This can be used to establish energy calibrations, as well as tosearch for the anti-matter content of the VHE cosmic ray flux. The shadow ofthe sun has also been observed with high significance.

The Milagrito water Cherenkov telescope operated for over a year. The mostprobable gamma-ray energy was ~1 TeV and the trigger rate was as high as 400Hz. We have developed an efficient technique for searching the entire sky forshort duration bursts of TeV photons. Such bursts may result from "traditional"gamma-ray bursts that were not in the field-of-view of any other instruments,the evaporation of primordial black holes, or some as yet undiscoveredphenomenon. We have begun to search the Milagrito data set for bursts ofduration 10 seconds. Here we will present the technique and the expectedresults. Final results will be presented at the conference.

Solar Energetic Particles from the 6 November 1997 solar flare/CME(coronalmass ejection) with energies exceeding 10 GeV have been detected by Milagrito,a prototype of the Milagro Gamma Ray Observatory. While particle accelerationbeyond 1 GeV at the Sun is well established, few data exist for protons or ionsbeyond 10 GeV. The Milagro observatory, a ground based water Cherenkov detectordesigned for observing very high energy gamma ray sources, can also be used tostudy the Sun. Milagrito, which operated for approximately one year in 1997/98,was sensitive to solar proton and neutron fluxes above ~5- 10 GeV. Milagritooperated in a scaler mode, which was primarily sensitive to muons, low energyphotons, and electrons, and the detector operated in a mode sensitive toshowers and high zenith angle muons. In its scaler mode, Milagrito registered arate increase coincident with the 6 November 1997 ground level event observedby Climax and other neutron monitors. A preliminary analysis suggests thepresence of >10 GeV particles.

The Milagro water Cherenkov detector near Los Alamos, New Mexico, has beenoperated as a sky monitor at energies of a few TeV between February 1997 andApril 1998. Serving as a test run for the full Milagro detector, Milagrito hastaken data during the strong and long-lasting 1997 flare of Mrk 501. We presentresults from the analysis of Mrk 501 and compare the excess and backgroundrates with expectations from the detector simulations.

Observing gamma ray bursts (GRBs) in the TeV energy range can be extremelyvaluable in providing insight to GRB radiation mechanisms and in constrainingsource distances. The Milagrito detector was an air shower array which used thewater Cherenkov technique to search for TeV sources. Data from this detectorwas analyzed to look for a TeV component of GRBs coincident with low energy-rays detected by the BATSE instrument on the Compton Gamma Ray Observatory. Asample of 54 BATSE GRBs which were in the field of view of the Milagritodetector during its lifetime (February 1997 to May 1998) was used.

The Milagrito water Cherenkov detector in the Jemez Mountains near LosAlamos, New Mexico took data from February 1997 to April 1998. Milagrito servedas a prototype for the larger Milagro detector, which has just begunoperations. Milagrito was the first large-aperture gamma-ray detector withsensitivity to gamma rays below 1 TeV. We report here on a search for steadyemission from point sources over most of the northern sky using data fromMilagrito.

Long-term bone marrow cultures have been useful in determining gene expression patterns in pre-B cells and in the identification of cytokines such as interleukin 7 (IL-7). We have developed a culture system to selectively grow populations of B lineage restricted progenitors (pro-B cells) from murine bone marrow. Pro-B cells do not grow in response to IL-7, Steel locus factor (SLF), or a combination of the two. c-kit, the SLF receptor, and the IL-7 receptor are both expressed by pro-B cells, indicating that the lack of response is not simply due to the absence of receptors. Furthermore, SLF is not necessary for the growth of pro-B cells since they could be expanded on a stromal line derived from Steel mice that produces no SLF. IL-7 responsiveness in pre-B cells is associated with an increase in n-myc expression and is correlated with immunoglobulin (Ig) gene rearrangements. Although members of the ets family of transcription factors and the Pim-1 kinase are expressed by pro-B cells, n-myc is not expressed. Pro-B cells maintain Ig genes in the germline configuration, which is correlated with a low level of recombination activating genes 1 and 2 (Rag-1 and 2) mRNA expression, but high expression of sterile mu and terminal deoxynucleotidyl transferase. Pro-B cells are unable to grow separated from the stromal layer by a porous membrane, indicating that stromal contact is required for growth. These results suggest that pro-B cells are dependent on alternative growth signals derived from bone marrow stroma and can be distinguished from pre-B cells by specific patterns of gene expression.