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Compositional End Members in Gale Crater, Mars
Geochemical data returned from the Mars Science Laboratory’s Curiosity rover over 1296 sols, has revealed a previously unforeseen martian geochemical complexity. Before Curiosity landed in Gale Crater, Martian SNC meteorite studies along with previous orbiter, rover and lander data showed Mars as being a predominantly basaltic planet with little magmatic differentiation. But through using ChemCam density contour plots to collate compositional data obtained by that instrument, we can identify 4 compositional end members in Gale sedimentary and igneous samples
Formative Evaluation of an Online Access to Justice Triage and Intake System
The objective of this project is to evaluate the usability of Legal Aid of Nebraska’s LawHelp Nebraska online intake and triage system. A mixed-methods approach consisting of observations, semi-structured interviews, and validated survey were used with 14 participants as they interacted with the system. A convenience sample was used through recruitment of clients at Legal Aid of Nebraska’s Omaha office during legal assistance walk-in hours. To analyze the qualitative data from the semi-structured interviews and retrospective observation forms, researchers used thematic analysis. For quantitative data collected through a survey, researchers used descriptive analysis and validated scoring. The project and results were used to comply with Legal Aid of Nebraska’s grant requirements for LawHelp Nebraska. Recommendations developed through the evaluation were given to Legal Aid of Nebraska’s administrators to make appropriate changes to the LawHelp Nebraska system
Duration discrimination of brief visual stimuli
Visual flash duration discrimination and decision theory analysis of effects of temporal and brightness difference
APPLICATION OF AN AVIAN BIOENERGETICS SIMULATION MODEL TO RED-WINGED BLACKBIRD - CROP RELATIONS
The impact of bird populations upon the properties or processes of ecosystems is mediated through patterns and magnitudes of energy flow. This impact may be either direct, by processing of large quantities of energy or nutrients, or indirect, through feedback control of other ecosystem rate processes or components. In either case, however, the impact is a result of the population dynamics and the pattern and magnitude of food consumption of the birds. Recent research by several groups points to a relatively small direct impact on birds on most natural ecosystems (Wiens 1973). Impact through feedback control, a more difficult relationship to study, is just beginning to receive close attention in a total systems framework. In managed ecosystems, however, where our interest is in either the bird population or its prey as an aesthetic or economic resource, the direct impacts are of considerable importance. These direct impacts are a reflection of prey consumption, which in turn is a result of the interactions of prey selection and energy demand. There is little field information available on either of these components for most bird populations, however, and we have therefore employed simulation modelling, coupled with existing information on dietary composition, to generate estimates of prey consumption rates and thus of potential impact. Our modelling tactic has been to stress generality and biological realism at the expense of precision (Levins 1966), since we are interested in models which are both robust and broadly applicable. Also, we recognize that the data base of the model is frequently imprecise, and it seems intuitively illogical to build extremely precise models for imprecise data inputs, even though this if often done
State of stress before and after the 1994 Northridge Earthquake
The state of tectonic stress in the epicentral area of the 17 January 1994, Northridge earthquake (Mw 6.7) is investigated by applying a stress inversion method to P-wave polarity data from earthquakes in Northridge from July 1981 to January 1994 and from the Northridge aftershocks during January 1994 to December 1995. A 3-D crustal model is used to trace the rays taking off from the hypocenter, which reduced the effects of large structural heterogeneities on the determination of the stress tensor. We found significant temporal changes of stress orientations induced by the Northridge earthquake. The principal pressure (P) axis is oriented N32°E from 1981 to June 1992, and N30°E from 28 June 1992 to 16 January 1994, suggesting that the stress field in Northridge was not affected by the 1992 Landers earthquake. During two weeks following the Northridge mainshock, the P-axis is oriented N13°E, which is a significant (17°) change from that before the earthquake (N30°E). Between February 1994 and August 1995 the P-axis orientation changes from N18°E to N26°E, and finally ends up at N34° by the end of 1995, which is close to that before the Northridge earthquake. These results suggest that the stresses rotated coseismically, then rotated more slowly back to their original orientation. The aftershocks caused by the mainshock changed the stress distribution in the crust, which showed up as a regional stress change. The stress recovery appears to have completed within two years after the mainshock, which is very short compared to the time scale of the earthquake cycle
Impact of COVID-19 on tuberculosis notifications
The COVID-19 pandemic has significantly impacted the control of diseases by overwhelming healthcare systems, and tuberculosis (TB) notifications may have been affected. This study aimed to analyze the impact of COVID-19 on TB notifications in the Sao Paulo State. This is a retrospective study examining TB notifications extracted from the TBweb database (Jan 2015 to Dec 2022). We conducted an interrupted time series (ITS) analysis of TB notifications using the declaration of the COVID-19 pandemic as the interrupting event (Bayesian causal impact analysis). A total of 177,103 notifications of TB incident cases were analyzed, revealing a significant decrease in 2020 (13%) and in 2021 (9%), which lost significance in 2022. However, changes were not associated with population density or the area of the regions. Future analyses of the effects of TB underdiagnosis might help describe the impact of underreporting on future TB incidence and mortality
Cell cycle-dependent phosphorylation of Theileria annulata schizont surface proteins
The invasion of Theileria sporozoites into bovine leukocytes is rapidly followed by the destruction of the surrounding host cell membrane, allowing the parasite to establish its niche within the host cell cytoplasm. Theileria infection induces host cell transformation, characterised by increased host cell proliferation and invasiveness, and the activation of anti-apoptotic genes. This process is strictly dependent on the presence of a viable parasite. Several host cell kinases, including PI3-K, JNK, CK2 and Src-family kinases, are constitutively activated in Theileria-infected cells and contribute to the transformed phenotype. Although a number of host cell molecules, including IkB kinase and polo-like kinase 1 (Plk1), are recruited to the schizont surface, very little is known about the schizont molecules involved in host-parasite interactions. In this study we used immunofluorescence to detect phosphorylated threonine (p-Thr), serine (p-Ser) and threonine-proline (p-Thr-Pro) epitopes on the schizont during host cell cycle progression, revealing extensive schizont phosphorylation during host cell interphase. Furthermore, we established a quick protocol to isolate schizonts from infected macrophages following synchronisation in S-phase or mitosis, and used mass spectrometry to detect phosphorylated schizont proteins. In total, 65 phosphorylated Theileria proteins were detected, 15 of which are potentially secreted or expressed on the surface of the schizont and thus may be targets for host cell kinases. In particular, we describe the cell cycle-dependent phosphorylation of two T. annulata surface proteins, TaSP and p104, both of which are highly phosphorylated during host cell S-phase. TaSP and p104 are involved in mediating interactions between the parasite and the host cell cytoskeleton, which is crucial for the persistence of the parasite within the dividing host cell and the maintenance of the transformed state
Seasonal and spatial variations in the ocean-coupled ambient wavefield of the Ross Ice Shelf
© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baker, M. G., Aster, R. C., Anthony, R. E., Chaput, J., Wiens, D. A., Nyblade, A., Bromirski, P. D., Gerstoft, P., & Stephen, R. A. Seasonal and spatial variations in the ocean-coupled ambient wavefield of the Ross Ice Shelf. Journal of Glaciology, 65(254), (2019): 912-925, doi:10.1017/jog.2019.64.The Ross Ice Shelf (RIS) is host to a broadband, multimode seismic wavefield that is excited in response to atmospheric, oceanic and solid Earth source processes. A 34-station broadband seismographic network installed on the RIS from late 2014 through early 2017 produced continuous vibrational observations of Earth's largest ice shelf at both floating and grounded locations. We characterize temporal and spatial variations in broadband ambient wavefield power, with a focus on period bands associated with primary (10–20 s) and secondary (5–10 s) microseism signals, and an oceanic source process near the ice front (0.4–4.0 s). Horizontal component signals on floating stations overwhelmingly reflect oceanic excitations year-round due to near-complete isolation from solid Earth shear waves. The spectrum at all periods is shown to be strongly modulated by the concentration of sea ice near the ice shelf front. Contiguous and extensive sea ice damps ocean wave coupling sufficiently so that wintertime background levels can approach or surpass those of land-sited stations in Antarctica.This research was supported by NSF grants PLR-1142518, 1141916, 1142126, 1246151 and 1246416. JC was additionally supported by Yates funds in the Colorado State University Department of Mathematics. PDB also received support from the California Department of Parks and Recreation, Division of Boating and Waterways under contract 11-106-107. We thank Reinhard Flick and Patrick Shore for their support during field work, Tom Bolmer in locating stations and preparing maps, and the US Antarctic Program for logistical support. The seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center at New Mexico Tech. Data collected are available through the IRIS Data Management Center under RIS and DRIS network code XH. The PSD-PDFs presented in this study were processed with the IRIS Noise Tool Kit (Bahavar and others, 2013). The facilities of the IRIS Consortium are supported by the National Science Foundation under Cooperative Agreement EAR-1261681 and the DOE National Nuclear Security Administration. The authors appreciate the support of the University of Wisconsin-Madison Automatic Weather Station Program for the data set, data display and information; funded under NSF grant number ANT-1543305. The Ross Ice Shelf profiles were generated using the Antarctic Mapping Tools (Greene and others, 2017). Regional maps were generated with the Generic Mapping Tools (Wessel and Smith, 1998). Topography and bathymetry data for all maps in this study were sourced from the National Geophysical Data Center ETOPO1 Global Relief Model (doi:10.7289/V5C8276M). We thank two anonymous reviewers for suggestions on the scope and organization of this paper
Systematic review and meta-analysis of the pharmacokinetics of benznidazole in the treatment of Chagas disease
Chagas disease is a neglected parasitic illness affecting approximately 8 million people, predominantly in Latin America. Benznidazole is the drug of choice for treatment, although its availability has been limited. A paucity of knowledge of the pharmacokinetic properties of this drug has contributed to its limited availability in several jurisdictions. The objective of this study was to conduct a systematic literature review and a Bayesian meta-analysis of pharmacokinetic studies to improve estimates of the basic pharmacokinetic properties of benznidazole. A systematic search of the Embase, Medline, LILACS, and SciELO (Scientific Electronic Library Online) databases was conducted. Eligible studies reported patient-level data from single-100-mg-dose pharmacokinetic evaluations of benznidazole in adults or otherwise provided data relevant to the estimation of pharmacokinetic parameters which could be derived from such studies. A Bayesian hierarchical model was used for analysis. Secondary data (i.e., data from studies that did not include patient-level, single-100-mg-dose data) were used for the generation of empirical priors for the Bayesian analysis. The systematic search identified nine studies for inclusion. Nine pharmacokinetic parameters were estimated, including the area under the concentration-time curve (AUC), the maximum concentration of drug in plasma (Cmax), the time to Cmax, the elimination rate constant (kel), the absorption rate constant (Ka), the absorption and elimination half-lives, the apparent oral clearance, and the apparent oral volume of distribution. The results showed consistency across studies. AUC and Cmax were 51.31 mg · h/liter (95% credible interval [CrI], 45.01, 60.28 mg · h/liter) and 2.19 mg/liter (95% CrI, 2.06, 2.33 mg/liter), respectively. Ka and kel were 1.16 h-1 (95% CrI, 0.59, 1.76 h-1) and 0.052 h-1 (95% CrI, 0.045, 0.059 h-1), respectively, with the corresponding absorption and elimination half-lives being 0.60 h (95% CrI, 0.38, 1.11 h) and 13.27 h (95% CrI, 11.79, 15.42 h), respectively. The oral clearance and volume of distribution were 2.04 liters/h (95% CrI, 1.77, 2.32 liters/h) and 39.19 liters (95% CrI, 36.58, 42.17 liters), respectively. A Bayesian meta-analysis was used to improve the estimates of the standard pharmacokinetic parameters of benznidazole. These data can inform clinicians and policy makers as access to this drug increases.Fil: Wiens, Matthew O.. University of British Columbia; CanadáFil: Kanters, Steve. Precision Global Health;Fil: Mills, Edward. Mc Master University; CanadáFil: Peregrina Lucano, Alejandro A.. Universidad de Guadalajara; MéxicoFil: Gold, Silvia. Fundación Mundo Sano; ArgentinaFil: Ayers, Dieter. Precision Global Health;Fil: Ferrero, Luis. Fundación Mundo Sano; ArgentinaFil: Krolewiecki, Alejandro Javier. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Salta. Instituto de PatologÃa Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de PatologÃa Experimental; Argentin
The association of statin use after cancer diagnosis with survival in pancreatic cancer patients: a SEER-medicare analysis.
BackgroundPancreatic cancer has poor prognosis and existing interventions provide a modest benefit. Statin has anti-cancer properties that might enhance survival in pancreatic cancer patients. We sought to determine whether statin treatment after cancer diagnosis is associated with longer survival in those with pancreatic ductal adenocarcinoma (PDAC).MethodsWe analyzed data on 7813 elderly patients with PDAC using the linked Surveillance, Epidemiology, and End Results (SEER) - Medicare claims files. Information on the type, intensity and duration of statin use after cancer diagnosis was extracted from Medicare Part D. We treated statin as a time-dependent variable in a Cox regression model to determine the association with overall survival adjusting for follow-up, age, sex, race, neighborhood income, stage, grade, tumor size, pancreatectomy, chemotherapy, radiation, obesity, dyslipidemia, diabetes, chronic pancreatitis and chronic obstructive pulmonary disease (COPD).ResultsOverall, statin use after cancer diagnosis was not significantly associated with survival when all PDAC patients were considered (HR = 0.94, 95%CI 0.89, 1.01). However, statin use after cancer diagnosis was associated with a 21% reduced hazard of death (Hazard ratio = 0.79, 95% confidence interval (CI) 0.67, 0.93) in those with grade I or II PDAC and to a similar extent in those who had undergone a pancreatectomy, in those with chronic pancreatitis and in those who had not been treated with statin prior to cancer diagnosis.ConclusionsWe found that statin treatment after cancer diagnosis is associated with enhanced survival in patients with low-grade, resectable PDAC
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