581 research outputs found
Crafting Relevant Community Partnerships Using Archives
Historically, archives have told the stories of the dominant society. Increasingly, archives are exploring and filling some of the silences left by the exclusion of many voices. Oral history is a way of actively collecting stories which may not exist in written form. Both the University of Nebraska at Omahaâs LGBTQ+ Voices: The Queer Omaha Archives Oral History Project and the University of Nebraska at Kearney Archives and Special Collectionsâ Coming to the Plains: Latin@ Stories in Central Nebraska project engage members of diverse communities in telling their own stories. This session will talk about the origins of each project, the challenges faced, the evolution of the projects, and future pathways. Specific issues discussed will include planning oral history projects, collaborating with communities, faculty, and students on all stages of an oral history project, gaining grant funding to scale up projects, and publicizing and sharing the products of oral histories
Assimilation de données d'humidité des sols pour la prévision de crues : comparaison d'un modÚle pluie-débit conceptuel et d'un modÚle intégrant une interface sol-végétation-atmosphÚre
Le but de cet article est de prĂ©senter une mĂ©thodologie de mise Ă jour des paramĂštres de modĂšles pluie-dĂ©bit en pĂ©riode de crue. Elle a Ă©tĂ© mise au point afin d'amĂ©liorer un des aspects de la gestion des rĂ©servoirs dans un contexte opĂ©rationnel de protection contre les crues: la rĂ©duction des incertitudes sur la prĂ©vision des dĂ©bits. L'originalitĂ© de la mĂ©thode proposĂ©e rĂ©side dans le fait que l'on utilise non seulement une information sur les dĂ©bits mais aussi une information sur l'humiditĂ© du sol. L'objectif de l'Ă©tude est d'Ă©valuer l'intĂ©rĂȘt de l'introduction de cette information supplĂ©mentaire. Pour cela, les donnĂ©es d'humiditĂ© du sol sont introduites au sein du modĂšle par l'intermĂ©diaire d'une relation de passage Ă©tablie entre l'humiditĂ© mesurĂ©e in situ et l'humiditĂ© calculĂ©e implicitement ou explicitement par les modĂšles. Cette mĂ©thodologie a Ă©tĂ© testĂ©e dans le cadre du projet europĂ©en AIMWATER sur quatre sous-bassins de la Seine en amont de Paris (France). Deux modĂšles pluie-dĂ©bit sont utilisĂ©s dans cette Ă©tude, un modĂšle conceptuel semi-emprique et un modĂšle conceptuel couplĂ© Ă un schĂ©ma de surface simulant une interface sol-vĂ©gĂ©tation-atmosphĂšre et permettant de calculer l'Ă©volution de l'humiditĂ© du sol Ă diffĂ©rentes profondeurs. Cette approche comparative Ă©tudie l'intĂ©rĂȘt d'un tel modĂšle couplĂ© par rapport au modĂšle conceptuel semi-empirique sans reprĂ©sentation explicite des phĂ©nomĂšnes se produisant Ă l'interface sol-vĂ©gĂ©tation-atmosphĂšre.Improving the accuracy of rainfall-runoff models and in particular their performances in flood prediction is a key point of continental hydrology. Methods have been developed to improve flood prediction in hydrology based on a better compliance of the model with current observations prior to its use in forecasting mode. This operation has been termed updating in hydrology and assimilation in meteorology. The fundamental idea is that if model predictions diverge from observations at a given time, there is little chance that future estimations will approach correct values. The improvement then comes from a correction of the trajectory of the model based on observations during the period preceding the day when a prediction into the immediate or long-term future is desired. This can be dealt with by a correction of model parameters, which is usually called "parameter updating".The inability of rainfall-runoff models to produce correct streamflow values generally translates into parameter uncertainty. Parameter calibration is the means used by a model structure to adjust to a given set of data. Therefore, a parameter updating methodology seems to be a natural way to amend errors in streamflow values. In this paper, a specific methodology of parameter updating is presented. The main feature of this method is that it does not carry out updating by reference only to recent streamflow observations, as classic procedures do, but also to soil moisture measurements, which can be retrieved daily from TDR probes. Indeed, it appears that the integration of soil moisture data allows better control of the evolution of the model and improves its performances, in particular in terms of forecasting.The aim of the research was to assess the usefulness of this additional soil moisture information. To this end, an approach has been suggested that gradually introduces additional information thanks to a constraint relationship between observed and modelled soil moisture. In fact, soil moisture can be calculated implicitly or explicitly by the model when extracting step-by-step the values of the model's store contents. This methodology was put forward for use in the European AIMWATER project on four catchments within the Seine River basin upstream of Paris (France). The other issue addressed in this paper was whether or not it is necessary to use a model that simulates explicitly the evolution of soil moisture at different depths. One can argue that if the model employed does not feature a store that can be identified closely to the observed soil moisture, there would be no possibility of benefiting from such measurements. On the other hand, it can be argued that if soil moisture is a model output, all the information drawn from soil moisture observations will be directed at improving this specific output at the expense of improving streamflow values. To answer this issue, two models were tested. The first model, GR4j, has no explicit counterpart for soil moisture measurements. The second one, GRHum, has been especially developed to introduce a two-layer soil reservoir that simulates the surface and sub-surface soil moisture.Since the aim of the present research was to analyse different ways of accounting for soil moisture, and to identify the one that offers the best prospects, several tests were carried out, using different relationships between observed and modelled soil moisture. Indeed, TDR probes give point measurements of soil moisture at several depths and several store contents can be taken into account in a constraint relationship.First, for both GR4j and GRHum models, tests showed that performances for flood forecasting are significantly improved when assimilating in situ measurements of soil moisture at a daily time-step, especially for the basins where poor simulations are obtained. It is also noteworthy that performances are very dependent on the items taken into account in a constraint relationship.Secondly, the GRHum model did not appear to be more efficient than the GR4j model when assimilating both streamflow and soil moisture data. However, the GRHum model gave the best results when assimilating only streamflow data, and superficial soil moisture seemed to fit the GRHum better than the GR4j model.Finally, although the tests required perfect foreknowledge of rainfall, the results of the research are encouraging from an operational point of view. Another interesting perspective is provided by the Earth Observation data. Indeed, previous studies have shown that soil moisture can be derived from EO data using, for example, microwave spaceborne Synthetic Aperture Radar (SAR) images (QUESNEY et al., 2000). This type of catchment-scale data could be more relevant than a local measure given by TDR probes (PAUWELS et al., 2002)
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Early tumor response to intraarterial or intravenous administration of carboplatin to treat naturally occurring lower urinary tract carcinoma in dogs.
BackgroundSurvival times and tumor responses associated with malignant neoplasia of the lower urinary tract are poor despite the vast array of current treatments. Therefore, the evaluation of alternative treatments, such as intraarterial administration of chemotherapy (IAC) should be considered.ObjectiveTo describe a technique for superselective catheterization for IAC and to evaluate initial tumor response by ultrasonography after both IAC and intravenous administration of chemotherapy (IVC).AnimalsClient-owned dogs with lower urinary tract neoplasia treated with either IVC (n = 15) or IAC (n = 11).MethodsRetrospective study. An arterial approach via the carotid or femoral artery was utilized to obtain superselective access and administer chemotherapy in the IAC cases. Medical record review was performed, data were recorded, and recorded variables were evaluated statistically.ResultsIntraarterial chemotherapy was successfully administered in all cases. There was a significantly greater decrease in longest unidimensional measurement in the IAC group as compared to the IVC group (P = .013). The IAC group was also significantly more likely to have a tumor response as assessed by modified RECIST guidelines (P = .049). Dogs in the IAC group were significantly less likely to develop anemia (P = .001), lethargy (P = .010) and anorexia (P = .024).Conclusion and clinical importanceThis study demonstrated the feasibility and efficacy of performing IAC for lower urinary tract neoplasia. Further investigation is necessary as the follow-up time was short and the impact on long-term outcome and survival was not determined
Drug-eluting Bead Chemoembolization for the Treatment of Nonresectable Hepatic Carcinoma in Dogs: A Prospective Clinical Trial
Abstract Background Effective treatment options for nonresectable hepatic carcinoma (HC) in dogs are limited. Hypothesis/Objective Objectives were to report outcomes, complications, and tumor responses via computed tomography (CT) assessment after drugâeluting bead transarterial chemoembolization (DEBâTACE) for nonresectable HC in dogs. The authors hypothesized that major complications would be uncommon and shortâterm CT assessment would demonstrate stable disease or partial response. Animals Clientâowned dogs (n = 16) with nonresectable HC. Methods Prospective, singleâarm clinical trial. Drugâeluting bead transarterial chemoembolization was performed to varying levels of blood flow stasis. Computed tomography imaging was compared before and approximately 12âweeks after initial treatment. Results Drugâeluting bead transarterial chemoembolization was successfully administered in all attempts. Based on percent change in elliptical tumor volume response (mL), stable disease (8/13; 62%) was the most common outcome followed by partial response (3/13; 23%) and progressive disease (2/13; 15%) with a median of 74âdays (range, 39â125) after initial treatment. Median tumor volume (mL) after DEBâTACE decreased in volume by 13% (range, 56% decrease to 77% increase). Mild complications consistent with postembolization syndrome occurred after 7/27 (26%) treatments. Major complications occurred after 3/27 (11%) treatments: hepatic abscess/septicemia (2) and cholecystitis/death (1), resulting in treatmentâinduced death after 2/27 (7%) treatments. Median survival time after treatment was 337âdays (range, 22â1061). Dogs with a presenting complaint of weight loss (P = .02) had a significantly shorter median survival time (126âdays; range, 46â337) than those dogs without prior history of weight loss (582âdays; range, 22â1061). Conclusions Drugâeluting bead transarterial chemoembolization for nonresectable HC is a feasible procedure, which promoted stable disease or partial response in 85% of dogs in this study sample
Photosynthetic and growth response of freshwater picocyanobacteria are strain-specific and sensitive to photoacclimation
We investigated the effect of different light conditions on primary production and growth rates of three closely related freshwater picocyanobacterial strains from three different ribotypes in laboratory cultures. The primary goal was to test whether not only different pigment types (PC-rich versus PE-rich) but also other physiological characteristics suggested by different phylogenetic positions could affect growth and photosynthetic rates of picocyanobacteria. Secondly, we tested whether photacclimation is strain specific. Experiments were conducted over light intensities ranging from 6 to 1500 ÎŒmol photons mâ2 sâ1 with cultures that were acclimated to low (10 ÎŒmol photons mâ2 sâ1) and moderate (100 ÎŒmol photons mâ2 sâ1) irradiance. The PE-rich strain was sensitive to high light conditions and reached highest photosynthesis and growth rates at low light intensities. The relative effect of photoacclimation was different between the two PC-rich strains, with one strain showing only moderate changes in growth rates in response to the light level used during the acclimation period. Overall, growth rates differed widely in response to light intensity and photoacclimation. Photoacclimation significantly affected both primary production and growth rates of all three strains investigated. We conclude that strain-specific photoacclimation adds to the niche partitioning among closely related freshwater picocyanobacteria
Uncovering selective excitations using the resonant profile of indirect inelastic x-ray scattering in correlated materials: Observing two-magnon scattering and relation to the dynamical structure factor
Resonant inelastic x-ray scattering (RIXS) is a spectroscopic technique which
has been widely used to study various elementary excitations in correlated and
other condensed matter systems. For strongly correlated materials, besides
boosting the overall signal the dependence of the resonant profile on incident
photon energy is still not fully understood. Previous endeavors in connecting
indirect RIXS, such as Cu K-edge for example where scattering takes place only
via the core-hole created as an intermediate state, with the charge dynamical
structure factor S(q,\omega) neglected complicated dependence on the
intermediate state configuration. To resolve this issue, we performed an exact
diagonalization study of the RIXS cross-section using the single-band Hubbard
model by fully addressing the intermediate state contribution. Our results are
relevant to indirect RIXS in correlated materials, such as high Tc cuprates. We
demonstrate that RIXS spectra can be reduced to S(q,\omega) when there is no
screening channel for the core-hole potential in the intermediate state. We
also show that two-magnon excitations are highlighted at the resonant photon
energy when the core-hole potential in the corresponding intermediate state is
poorly screened. Our results demonstrate that different elementary excitations
can be emphasized at different intermediate states, such that selecting the
exact incident energy is critical when trying to capture a particular
elementary excitation.Comment: 11 pages, 3 figure
Phase diagram and optical conductivity of the one-dimensional spinless Holstein model
The effects of quantum lattice fluctuations on the Peierls transition and the
optical conductivity in the one-dimensional Holstein model of spinless fermions
have been studied by developing an analytical approach, based on the unitary
transformation method. We show that when the electron-phonon coupling constant
decreases to a finite critical value the Peierls dimerization is destroyed by
the quantum lattice fluctuations. The dimerization gap is much more reduced by
the quantum lattice fluctuations than the phonon order parameter. The
calculated optical conductivity does not have the inverse-square-root
singularity but have a peak above the gap edge and there exists a significant
tail below the peak. The peak of optical-conductivity spectrum is not directly
corresponding to the dimerized gap. Our results of the phase diagram and the
spectral-weight function agree with those of the density matrix renormalization
group and the exact diagonalization methods.Comment: 9 pages, 4 figures include
Exploring high-end climate change scenarios for flood protection of the Netherlands
This international scientific assessment has been carried out at the request of the Dutch Delta Committee. The "Deltacommissie" requested that the assessment explore the high-end climate change scenarios for flood protection of the Netherlands. It is a state-ofâthe art scientific assessment of the upper bound values and longer term projections (for sea level rise up to 2200) of climate induced sea level rise, changing storm surge conditions and peak discharge of river Rhine. It comprises a review of recent studies, model projections and expert opinions of more than 20 leading climate scientists from different countries around the North Sea, Australia and the US
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