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Search Results: 1 - 10 of 462317 matches for " A. France "
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Relating Cone Penetration and Rutting Resistance to Variations in Forest Soil Properties and Daily Moisture Fluctuations  [PDF]
Marie-France Jones, Paul A. Arp
Open Journal of Soil Science (OJSS) , 2017, DOI: 10.4236/ojss.2017.77012
Abstract: Soil resistance to penetration and rutting depends on variations in soil texture, density and weather-affected changes in moisture content. It is therefore difficult to know when and where off-road traffic could lead to rutting-induced soil disturbances. To establish some of the empirical means needed to enable the “when” and “where” determinations, an effort was made to model the soil resistance to penetration over time for three contrasting forest locations in Fredericton, New Brunswick: a loam and a clay loam on ablation/ basal till, and a sandy loam on alluvium. Measurements were taken manually with a soil moisture probe and a cone penetrometer from spring to fall at weekly intervals. Soil moisture was measured at 7.5 cm soil depth, and modelled at 15, 30, 45 and 60 cm depth using the Forest Hydrology Model (ForHyM). Cone penetration in the form of the cone index (CI) was determined at the same depths. These determinations were not only correlated with measured soil moisture but were also affected by soil density (or pore space), texture, and coarse fragment and organic matter content (R2 = 0.54; all locations and soil depths). The resulting regression-derived CI model was used to emulate how CI would generally change at each of the three locations based on daily weather records for rain, snow, and air temperature. This was done through location-initialized and calibrated hydrological and geospatial modelling. For practical interpretation purposes, the resulting CI projections were transformed into rut-depth estimates regarding multi-pass off-road all-terrain vehicle traffic.
Editorial
France A. Córdova
JPUR : Journal of Purdue Undergraduate Research , 2011,
Abstract: Dr. France A. Córdova was appointed Purdue University’s eleventh president on July 16, 2007, as well as professor of physics and astronomy for the University. Prior to joining Purdue, she served as chancellor and distinguished professor of physics and astronomy at the University of California (UC) Riverside from 2002 to 2007. An internationally recognized astrophysicist, Córdova served from 1996 to 2002 as a professor of physics and vice chancellor for research at UC Santa Barbara and initiated a “Research Across Disciplines” program that funded and encouraged both interdisciplinary and “blue sky” projects. Before joining UC Santa Barbara, she was chief scientist at NASA from 1993 to 1996, serving as the primary scientific advisor to the NASA administration and the principal interface between NASA headquarters and the broader scientific community. In that role she evaluated the science mission and budget for NASA and worked with the National Science and Technology Council, federal government agencies, and National Academies on a broad range of science policy initiatives.
XMM-Newton observes flaring in the polar UZ For during a low state
Dirk Pandel,France A. Cordova
Physics , 2002, DOI: 10.1046/j.1365-8711.2002.05846.x
Abstract: During an XMM-Newton observation, the eclipsing polar UZ For was found in a peculiar state with an extremely low X-ray luminosity and occasional X-ray and UV flaring. For most of the observation, UZ For was only barely detected in X-rays and about 800 times fainter than during a high state previously observed with ROSAT. A transient event, which lasted about 900 s, was detected simultaneously by the X-ray instruments and, in the UV, by the Optical Monitor. The transient was likely caused by the impact of 10^17-10^18 g of gas on the main accretion region of the white dwarf. The X-ray spectrum of the transient is consistent with 7 keV thermal bremsstrahlung from the shock-heated gas in the accretion column. A soft blackbody component due to reprocessing of X-rays in the white dwarf atmosphere is not seen. The likely origin of the UV emission during the transient is cyclotron radiation from the accretion column. We conclude from our analysis that the unusual flaring during the low state of UZ For was caused by intermittent increases of the mass transfer rate due to stellar activity on the secondary.
Improved Hybrid Circuit Assembly Yields and Reliability by Glassivation of the Semiconductor Chip
B. C. Heap,S. A. France
Active and Passive Electronic Components , 1977, DOI: 10.1155/apec.4.117
Abstract:
The X-ray Behavior of Two CVs: TT Ari and DP Leo
Craig R. Robinson,France A. Cordova
Physics , 1993,
Abstract: We present ROSAT PSPC observations of the nova-like, or intermediate polar, TT Ari and the eclipsing polar DP Leo. Observations of TT Ari were performed as part of a simultaneous multiwavelength campaign. The X-ray spectrum of TT Ari from ROSAT was combined with Ginga observations to suggest the presence of three distinct emission components: an optically thin plasma, a dominating bremsstrahlung continuum and one or more iron emission lines. Simultaneous and later IUE observations show modulation in the absorption component of the P Cygni-like CIV line on the spectroscopic period indicating a complex wind structure. Three eclipses were observed from the DP Leo system with intensity dips, not previously observed, occurring prior to each eclipse. The dips are interpreted as the eclipse of the main emission region by an accretion stream varying in impact position or stream shape with time. The DP Leo spectrum is well fit by either a 25 eV blackbody or a soft power law. No evidence exists for accretion onto the stronger magnetic pole and severe limits were placed upon the flux from any hard bremsstrahlung component. We constrained distances to this system based upon model fits to the data.
EVALUACION DE CEPAS NATIVAS DE Metarhizium anisopliae var. anisopliae SOBRE Otiorhynchus sulcatus Fab. (COLEOPTERA: CURCULIONIDAE)
Gerding G.,Macarena; France I.,Andrés; Cisternas A.,Ernesto;
Agricultura Técnica , 2000, DOI: 10.4067/S0365-28072000000300002
Abstract: the pathogenicity of three isolates of metarhizium anisopliae var. anisopliae against the black vine weevil (otiorhynchus sulcatus) was evaluated in a laboratory test. the isolates were applied in increasing concentrations (0 to 108 conidia ml-1) to the last instar larvae. larval mortality was evaluated for 20 days, and lethal concentration lc50 lc90, and mortality rates were calculated. the three isolates varied (p£ 0.01) in the rate of mortality at different concentrations. the lc50 and lc90 for the most virulent isolate were about 106 and 108 conidia ml-1, respectively. future field studies will determine the potential of this fungus as a biological control agent for otiorhynchus sulcatus in chile.
EVALUACION DE CEPAS NATIVAS DE Metarhizium anisopliae var. anisopliae SOBRE Otiorhynchus sulcatus Fab. (COLEOPTERA: CURCULIONIDAE) Evaluation of Chilean strains of Metarhizium anisopliae var. anisopliae against Otiorhynchus sulcatus Fab. (Coleoptera: Curculionidae)
Macarena Gerding G.,Andrés France I.,Ernesto Cisternas A.
Agricultura Técnica , 2000,
Abstract: Se evaluó en laboratorio la patogenicidad de tres aislamientos de Metarhizium anisopliae var. anisopliae sobre el gorgojo de la frutilla (Otiorhynchus sulcatus). Los aislamientos fueron aplicados en concentraciones crecientes (0 a 10(8) conidias mL-1) sobre larvas en el último estadío de desarrollo. Se evaluó durante 20 días la mortalidad de larvas, calculándose la concentración letal CL50 y CL90 , y la tasa de mortalidad. La tasa de mortalidad a distintas concentraciones fue distinta para los tres aislamientos (P<= 0,01). La CL50 y CL90 para el aislamiento más agresivo, fue de 10(6) y 10(8) respectivamente. Futuros estudios a nivel de campo permitirán determinar el potencial de este hongo como agente de control biológico de O. sulcatus en Chile. The pathogenicity of three isolates of Metarhizium anisopliae var. anisopliae against the black vine weevil (Otiorhynchus sulcatus) was evaluated in a laboratory test. The isolates were applied in increasing concentrations (0 to 10(8) conidia mL-1) to the last instar larvae. Larval mortality was evaluated for 20 days, and lethal concentration LC50 LC90, and mortality rates were calculated. The three isolates varied (P<= 0.01) in the rate of mortality at different concentrations. The LC50 and LC90 for the most virulent isolate were about 10(6) and 10(8) conidia mL-1, respectively. Future field studies will determine the potential of this fungus as a biological control agent for Otiorhynchus sulcatus in Chile.
Restoring the Balance: First Nations Women, Community, and Culture
María del Carmen Rodríguez de France
International Indigenous Policy Journal , 2010,
Abstract: With empowering stories and histories from twelve Aboriginal women who are leaders in different contexts and communities, the book acknowledges and celebrates the contributions of Aboriginal women to diverse fields of work and disciplines such as art, culture, politics, language, law, community, education, and social activism. About the Authors Eric Guimond is an assistant director at the Strategic Research and Analysis Directorate at Indian and Northern Affairs Canada. Gail Guthrie Valaskakis was a Distinguished Professor Emeritus of Concordia University and was a leading authority on Aboriginal Media and Communication. She passed away in 2007. Madeleine Dion Stout is a former nurse and founding director of the Centre of Aboriginal Education, Research, and Culture at Carleton University.
A Fast Flare and Direct Redshift Constraint in Far-UV Spectra of the Blazar S50716+714
Charles W. Danforth,Krzysztof Nalewajko,Kevin France,Brian A. Keeney
Physics , 2012, DOI: 10.1088/0004-637X/764/1/57
Abstract: The BL Lacertae object S50716+714 is one of the most studied blazars on the sky due to its active variability and brightness in many bands, including VHE gamma rays. We present here two serendipitous results from recent far-ultraviolet spectroscopic observations by the Cosmic Origins Spectrograph onboard the Hubble Space Telescope. First, during the course of our 7.3 hour HST observations, the blazar increased in flux rapidly by ~40% (-0.45 mag/h) followed by a slower decline (+0.36 mag/h) to previous far-UV flux levels. We model this flare using asymmetric flare templates and constrain the physical size and energetics of the emitting region. Furthermore, the spectral index of the object softens considerably during the course of the flare from alpha(nu)=-1.0 to alpha(nu)=-1.4. Second, we constrain the source redshift directly using the ~30 intervening absorption systems. A system at z=0.2315 is detected in Lya, Lyb, OVI, and NV and defines the lower bound on the source redshift. No absorbers are seen in the remaining spectral coverage (0.2315
Characteristics of symptoms of imminent eclampsia: A case referent study from a tertiary hospital in Tanzania  [PDF]
John France, Projestine S. Muganyizi
Open Journal of Obstetrics and Gynecology (OJOG) , 2012, DOI: 10.4236/ojog.2012.23065
Abstract: Background: Maternal mortality in developing countries is unacceptably high with eclampsia being consistently among the top causes. As yet, primary prevention of this complication is not possible since causes of preeclampsia are largely unknown and bio-chemical, hematological and radiological markers have proved unsuitable for routine prediction of eclamptic fits. Although headache, visual disturbance, abdominal pain, nausea, and vomiting are routinely elicited when managing pre-eclampsia and have been reported to predict eclamptic fits, the literature attempting to characterize them is scanty. We sought to establish characteristics of the prodromal symptoms of eclampsia and compare them with similar symptoms as experienced by normotensive pregnant women at Muhimbili National Hospital (MNH) in Tanzania. Methods: This study was conducted at MNH in 2010 by enrolling 123 eclamptic and 123 normotensive women. Women in the two groups were interviewed about their experiences and characteristics of headache, visual disturbances, abdominal pain, nausea and vomiting using a semi structured questionnaire. The severity, nature and other characteristics of the symptoms were assessed using standard scale/methods and data compared among the two groups. Results: Prodromal symptoms of eclampsia were present in 90% of eclamptic women. Headache was more frequent among eclamptic women (88%) than the normotensive (43%), p < 0.001). The symptom was also more perceived as severe among eclamptic (46.3%) than the normotensive (5.7%), p < 0.001. The most frequent location for headache was frontal in 65.7% of eclamptic women compared to frontal (41.5%) or generalized (39.6%) for the normotensive. Likewise, visual problems were significantly more frequent among eclamptic women (39%) compared to the normotensive (3%), p < 0.001. Upper abdominal pain was significantly more reported by eclamptic (36%) than normotensive women (0.9%), p = 0.001. The general occurrence of abdominal pain, nausea and vomiting was not significantly different in the two groups. The time lag from development of a symptom to eclamptic fit was up to seven days for most symptoms except visual disturbances of which 98% developed fits within 12 hours. Conclusion: Whereas the prodromal symptoms of eclampsia and similar symptoms in normotensive women were common, the characteristics of headache and visual disturbance differ significantly in the two groups. The knowledge of these differences could be utilized to improve the quality of management of pre eclamptic women in order to prevent eclampsia.
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