348 research outputs found
Do You See What I See? Problems with Juror Bias in Viewing Body-Camera Video Evidence
In the wake of the Michael Brown shooting in Ferguson, Missouri, advocates and activists called for greater oversight and accountability for police. One of the measures called for and adopted in many jurisdictions was the implementation of body cameras in police departments. Many treated this implementation as a sign of change that police officers would be held accountable for the violence they perpetrate. This Note argues that although body-camera footage may be useful as one form of evidence in cases of police violence, lawyers and judges should be extremely careful about how it is presented to the jury. Namely, the jury should be made aware of their own implicit biases and of the limited nature of the footage. Taking a look at the biases that all jurors hold as well as the inherent subjectivity of video footage, this Note shows how implicit biases and the myth of video objectivity can create problems in viewing body-camera footage and the footage should, therefore, be treated carefully when introduced at trial
Os isotopic composition and Os and Re distribution in the active mound of the TAG hydrothermal system, Mid-Atlantic Ridge
Drilling during ODP Leg 158 took place on the active mound of the TAG hydrothermal field on the Mid-Atlantic Ridge. The dominant mineral precipitating from the hydrothermal fluid is pyrite. Its Re and Os concentration and the Os isotopic composition provide constraints on the nature of the hydrothermal fluid circulating in the TAG mound. The 187Os/186Os ratios of massive pyrite samples vary from 4.9 to 8.9. The highest ratios have been observed in the upper part of the sulfide mountain (<20 mbsf) and the lowest in the stockwork zone at ~80 mbsf. This range of Os isotopic compositions is likely the result of mixing of seawater with hydrothermal fluid. The Os concentrations are very low, ranging from 0.04 to 4.2 ppt, and the massive pyrite zone at the top of the mound is enriched in Os relative to the interior of the hydrothermal system. A hyperbolic relationship between Os isotopic composition and Os concentration reflects the systematic addition of seawater-derived Os to the hydrothermal Os component at stratigraphically shallower levels. From this relationship it is estimated that pyrite precipitating from the hydrothermal fluid contains 0.02 to 0.04 ppt Os provided the 187Os/186Os value of the fluid ranges from about 1.3 to 4.7. Because of the great mobility of Os in the high-temperature hydrothermal system, it is assumed that its partition coefficient between pyrite and hydrothermal fluid is <1. This implies that the hydrothermal fluid contains more than 0.02 ppt Os. The occurrence of anhydrite-rich lithologies at ~30–40 mbsf corroborates that seawater is penetrating the hydrothermal system and contaminating the hydrothermal fluid circulating in the upper part of the mound. This partly explains why the Os of sulfides that precipitated above this level has a strong seawater-like isotopic signature. In addition, the massive pyrite zone of the upper part of the TAG mound formed by accumulation of sulfides derived from chimneys and the fall-out material of the hydrothermal plume above the TAG field. Both sulfide components formed during mixing of seawater and hydrothermal fluid and their Os should also have a distinct seawater component. These processes, especially the entrainment of seawater, appear to control the distribution of Os and Re within the hydrothermal system. The Os enrichment in the upper part of the mound can be explained if the element is co-precipitated with sulfides or adsorbed on mineral surface during the accumulation of sulfides on the TAG mound. As a significant amount of Os can be dissolved in the hydrothermal fluid, remobilization of Os within the hydrothermal system could lead to further Os enrichment at the top of the mound but to very low Os concentrations in the stockwork zone. The Re concentrations indicate a distribution opposite to that of Os: the highest concentrations of about 60 ppb have been observed more than 15 mbsf, but the concentrations decrease from 50 to 2 ppb in samples from the top of the sulfide mound (<15 mbsf). The behavior of Re appears to be controlled by the redox conditions in the TAG hydrothermal system, which, in turn, could be determined by the relative proportions of oxidized seawater and reduced hydrothermal fluid. Deep within the mound, where the hydrothermal fluid component dominates, Re is rather immobile and becomes concentrated. In the upper part of the sulfide mound where larger quantities of seawater mix with the fluid, however, the redox potential should be more oxidizing, and Re would be more soluble and released to the ocean
Oxidative stress as markers in identification of aluminum-tolerant peach tree rootstock cultivars and clonal selections.
Abstract: Peach rootstock and scion cultivars are selected in breeding programs considering resistance to pests and diseases, salt tolerance, drought tolerance, and vigor. However, rootstock tolerance to aluminum (Al), which is markedly present in tropical and subtropical soils of the world, is not considered. Thus, it is essential to define potential markers that can contribute to the selection of Al-resistant or Al-tolerant peach rootstocks. The objective of this study was to identify Al-tolerant peach tree rootstock cultivars and clonal selections using physiological and oxidative stress variables. A completely randomized experimental design was used in a 13 (rootstock cultivars and clonal selections) × 2 (with and without Al) factorial arrangement, with three replications. Nursery peach trees of own-rooted ‘BRS Mandinho’ (without rootstock) and nursery trees of ‘BRS Mandinho’ grafted on different rootstock cultivars and clonal selections were grown in a hydroponic system, consisting of two treatments, with and without 100 mg L-1 of Al. Dry biomass, photosynthetic variables, pigment concentration, hydrogen peroxide content, membrane lipid peroxidation, and activity of the antioxidant enzymes were evaluated. The total dry matter production of the own-rooted ‘BRS Mandinho’ trees and the SS-CHI-09-39 and SS-CHI-09-40 selections is affected by the Al presence, representing a decline of 35.4, 37.2, and 24.4 %, respectively, compared to the treatment with Al. The highest total dry matter production in Al presence was observed for the ‘Sharpe’ rootstock. ‘Capdeboscq’, DB-SEN-09-23, FB-ESM-09-43, JB-ESM-09-13, JAH-MAC-09-77, SAS-SAU-09-71, and VEH-GRA-09-55 rootstock selections are tolerant to Al. The use of physiological and biochemical variables shows potential for the selection of clonal rootstocks tolerant or resistant to Al. Resumo: Os porta-enxertos e cultivares de pessegueiro são selecionados em programas de melhoramento considerando a resistência a pragas e doenças, tolerância ao sal, tolerância à seca e vigor. Contudo, a tolerância do porta-enxerto ao alumínio (Al), que está marcadamente presente nos solos tropicais e subtropicais do mundo, não é considerada. Assim, é essencial definir potenciais marcadores que possam contribuir para a seleção de porta-enxertos de pessegueiro resistentes ou tolerantes ao Al. O objetivo deste estudo foi identificar cultivares de porta-enxertos de pessegueiro tolerantes ao Al e seleções clonais utilizando variáveis fisiológicas e de estresse oxidativo. O delineamento experimental utilizado foi inteiramente casualizado, em arranjo fatorial 13 (cultivares de porta-enxertos e seleções clonais) x 2 (com e sem Al), com três repetições. Pessegueiros de mudas 'BRS Mandinho' de raiz própria (sem porta-enxerto) e mudas de 'BRS Mandinho' enxertados em diferentes cultivares de porta-enxertos e seleções clonais foram cultivados em sistema hidropônico, composto por dois tratamentos, com e sem 100 mg L- 1 de Al. Foram avaliadas biomassa seca, variáveis fotossintéticas, concentração de pigmentos, teor de peróxido de hidrogênio, peroxidação lipídica de membrana e atividade de enzimas antioxidantes. A produção total de matéria seca das árvores 'BRS Mandinho' de raiz própria e das seleções SS-CHI-09-39 e SS-CHI-09-40 é afetada pela presença de Al, representando um declínio de 35,4, 37,2 e 24,4 %, respectivamente, em comparação ao tratamento com Al. A maior produção total de matéria seca na presença de Al foi observada para o porta-enxerto ‘Sharpe’. 'Capdeboscq', DB-SEN-09-23, FB-ESM-09-43, JB-ESM-09-13, JAH-MAC-09-77, SAS-SAU-09-71 e VEH-GRA-09 -55 seleções de porta-enxertos são tolerantes ao Al. A utilização de variáveis fisiológicas e bioquímicas apresenta potencial para seleção de porta-enxertos clonais tolerantes ou resistentes ao Al
Nucleosynthetic osmium isotope anomalies in acid leachates of the Murchison meteorite
We present osmium isotopic results obtained by sequential leaching of the
Murchison meteorite, which reveal the existence of very large internal
anomalies of nucleosynthetic origin. The Os isotopic anomalies are correlated,
and can be explained by the variable contributions of components derived from
the s, r and p-processes of nucleosynthesis. Much of the s-process rich osmium
is released by relatively mild leaching, suggesting the existence of an easily
leachable s-process rich presolar phase, or alternatively, of a chemically
resistant r-process rich phase. The s-process composition of Os released by
mild leaching diverges slightly from that released by aggressive digestion
techniques, perhaps suggesting that the presolar phases attacked by these
differing procedures condensed in different stellar environments. The
correlation between 190Os and 188Os can be used to constrain the s-process
190Os/188Os ratio to be 1.275 pm 0.043. Such a ratio can be reproduced in a
nuclear reaction network for a MACS value for 190Os of ~200 pm 22 mbarn at 30
keV. We also present evidence for extensive internal variation of 184Os
abundances in the Murchison meteorite. This suggests that p process rich
presolar grains (e.g., supernova condensates) may be present in meteorites in
sufficient quantities to influence the Os isotopic compositions of the
leachates.Comment: 40 pages, 9 figures, 2 tables. Accepted for publication in Earth and
Planetary Science Letter
Evidence for weathering and volcanism during the PETM from Arctic Ocean and Peri-Tethys osmium isotope records
Sudden global warming during the Paleocene–Eocene Thermal Maximum (PETM, 55.9 Ma) occurred because of the rapid release of several thousand gigatonnes of isotopically light carbon into the oceans and atmosphere; however, the cause of this release is not well understood. Some studies have linked carbon injection to volcanic activity associated with the North Atlantic Igneous Province (NAIP), while others have emphasised carbon cycle feedbacks associated with orbital forcing. This study presents the osmium isotope compositions of mudrocks that were deposited during the PETM at four locations (one from the Arctic Ocean, and three from the Peri-Tethys). The Os-isotope records all exhibit a shift of similar magnitude towards relatively radiogenic values across the PETM. This observation confirms that there was a transient, global increase in the flux of radiogenic Os from the weathering of continental rocks in response to elevated temperatures at that time. The tectonic effects of NAIP volcanic emplacement near the onset of the PETM is recorded by anomalously radiogenic Os-isotope compositions of PETM-age Arctic Ocean samples, which indicate an interval of hydrographic restriction that can be linked tectonic uplift due to hotspot volcanism in the North Atlantic seaway. The Peri-Tethys data also document a transient, higher flux of unradiogenic osmium into the ocean near the beginning of the PETM, most likely from the weathering of young mafic rocks associated with the NAIP. These observations support the hypothesis that volcanism played a major role in triggering the cascade of environmental changes during the PETM, and highlight the influence of paleogeography on the Os isotope characteristics of marine water masses
Treatment of active lupus nephritis with the novel immunosuppressant 15-deoxyspergualin: an open-label dose escalation study
Introduction: As the immunosuppressive potency of 15-deoxyspergualin (DSG) has been shown in the therapy of renal transplant rejection and Wegener's granulomatosis, the intention of this study was to evaluate the safety of DSG in the therapy of lupus nephritis (LN). Methods: Patients with histologically proven active LN after prior treatment with at least one immunosuppressant were treated with 0.5 mg/kg normal body weight/day DSG, injected subcutaneously for 14 days, followed by a break of one week. These cycles were repeated to a maximum of 9 times. Doses of oral corticosteroids were gradually reduced to 7.5 mg/day or lower by cycle 4. Response was measured according to a predefined decision pattern. The dose of DSG was adjusted depending on the efficacy and side effects. Results: 21 patients were included in this phase-I/II study. After the first DSG injection, one patient was excluded from the study due to renal failure. 5 patients dropped out due to adverse events or serious adverse events including fever, leukopenia, oral candidiasis, herpes zoster or pneumonia. 11/20 patients achieved partial (4) or complete responses (7), 8 were judged as treatment failures and one patient was not assessable. 12 patients completed all 9 cycles; in those patients, proteinuria decreased from 5.88g/day to 3.37g/day (P = 0.028), Selena-SLEDAI decreased from 17.6 to 11.7. In 13/20 patients, proteinuria decreased by at least 50%; in 7 patients to less than 1g/day. Conclusions: Although the number of patients was small, we could demonstrate that DSG provides a tolerably safe treatment for LN. The improvement in proteinuria encourages larger controlled trials
The δ44Ca-temperature calibration on fossil and cultured Globigerinoides sacculifer: New tool for reconstruction of past sea surface temperatures
We report direct δ44Ca-temperature calibration on cultured and fossil calcite foraminifera, showing that Ca isotopes are potentially a new proxy for past sea surface temperatures (SST). Samples have been analyzed using a 43Ca-48Ca double spike and thermal ionization mass spectrometry (TIMS). In order to avoid species-dependent isotope fractionation we focused our investigations on a single foraminifera species (Globigerinoides sacculifer), which is known to inhabit shallow euphotic waters in tropical and subtropical oceans. Ca isotope measurements were performed on cultured G. sacculifer that grew in seawater kept at temperatures of 19.5°, 26.5°, and 29.5°C. A δ44Ca change of 0.24 ± 0.02 per 1°C is defined by the weighted linear regression through reproduced δ44Ca data of the three temperatures (95% confidence level). Application of this new method to fossil G. sacculifer of an Equatorial East Atlantic sediment core (GeoB1112; 5°46.7′S, 10°45.0′W, 3125 m) indicates that the δ44Ca difference between marine isotope stage 1 (MIS-1) and MIS-2 is 0.71 ± 0.24. According to the current δ44Ca-temperature calibration this value corresponds to a temperature difference between MIS-1 and MIS-2 of ∼3.0 ± 1.0°C
The amyloid imaging for the prevention of Alzheimer's disease consortium: A European collaboration with global impact
Background: Amyloid-β (Aβ) accumulation is considered the earliest pathological change in Alzheimer's disease (AD). The Amyloid Imaging to Prevent Alzheimer's Disease (AMYPAD) consortium is a collaborative European framework across European Federation of Pharmaceutical Industries Associations (EFPIA), academic, and ‘Small and Medium-sized enterprises’ (SME) partners aiming to provide evidence on the clinical utility and cost-effectiveness of Positron Emission Tomography (PET) imaging in diagnostic work-up of AD and to support clinical trial design by developing optimal quantitative methodology in an early AD population. The AMYPAD studies: In the Diagnostic and Patient Management Study (DPMS), 844 participants from eight centres across three clinical subgroups (245 subjective cognitive decline, 342 mild cognitive impairment, and 258 dementia) were included. The Prognostic and Natural History Study (PNHS) recruited pre-dementia subjects across 11 European parent cohorts (PCs). Approximately 1600 unique subjects with historical and prospective data were collected within this study. PET acquisition with [18F]flutemetamol or [18F]florbetaben radiotracers was performed and quantified using the Centiloid (CL) method. Results: AMYPAD has significantly contributed to the AD field by furthering our understanding of amyloid deposition in the brain and the optimal methodology to measure this process. Main contributions so far include the validation of the dual-time window acquisition protocol to derive the fully quantitative non-displaceable binding potential (BPND), assess the value of this metric in the context of clinical trials, improve PET-sensitivity to emerging Aβ burden and utilize its available regional information, establish the quantitative accuracy of the Centiloid method across tracers and support implementation of quantitative amyloid-PET measures in the clinical routine. Future steps: The AMYPAD consortium has succeeded in recruiting and following a large number of prospective subjects and setting up a collaborative framework to integrate data across European PCs. Efforts are currently ongoing in collaboration with ARIDHIA and ADDI to harmonize, integrate, and curate all available clinical data from the PNHS PCs, which will become openly accessible to the wider scientific community
Prevention of dementia using mobile phone applications (PRODEMOS): A multinational, randomised, controlled effectiveness–implementation trial
Background: The expected increase of dementia prevalence in the coming decades will mainly be in low-income and middle-income countries and in people with low socioeconomic status in high-income countries. This study aims to reduce dementia risk factors in underserved populations at high-risk using a coach-supported mobile health (mHealth) intervention. Methods: This open-label, blinded endpoint, hybrid effectiveness–implementation randomised controlled trial (RCT) investigated whether a coach-supported mHealth intervention can reduce dementia risk in people aged 55–75 years of low socioeconomic status in the UK or from the general population in China with at least two dementia risk factors. The primary effectiveness outcome was change in cardiovascular risk factors, ageing, and incidence of dementia (CAIDE) risk score from baseline to after 12–18 months of intervention. Implementation outcomes were coverage, adoption, sustainability, appropriateness, acceptability, fidelity, feasibility, and costs assessed using a mixed-methods approach. All participants with complete data on the primary outcome, without imputation of missing outcomes were included in the analysis (intention-to-treat principle). This trial is registered with ISRCTN, ISRCTN15986016, and is completed. Findings: Between Jan 15, 2021, and April 18, 2023, 1488 people (601 male and 887 female) were randomly assigned (734 to intervention and 754 to control), with 1229 (83%) of 1488 available for analysis of the primary effectiveness outcome. After a mean follow-up of 16 months (SD 2·5), the mean CAIDE score improved 0·16 points in the intervention group versus 0·01 in the control group (mean difference –0·16, 95% CI –0·29 to –0·03). 1533 (10%) invited individuals responded; of the intervention participants, 593 (81%) of 734 adopted the intervention and 367 (50%) of 734 continued active participation throughout the study. Perceived appropriateness (85%), acceptability (81%), and fidelity (79%) were good, with fair overall feasibility (53% of intervention participants and 58% of coaches), at low cost. No differences in adverse events between study arms were found. Interpretation: A coach-supported mHealth intervention is modestly effective in reducing dementia risk factors in those with low socioeconomic status in the UK and any socioeconomic status in China. Implementation is challenging in these populations, but those reached actively participated. Whether this intervention will result in less cognitive decline and dementia requires a larger RCT with long follow-up. Funding: EU Horizon 2020 Research and Innovation Programme and the National Key R&D Programmes of China. Translation: For the Mandarin translation of the abstract see Supplementary Materials section
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