Data Feminism D'Ignazio, Catherine; Klein, Lauren F
The MIT Press eBooks,
03/2020
eBook
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A new way of thinking about data science and data ethics that is informed by the ideas of intersectional feminism.
The open access edition of this book was made possible by generous funding from the ...MIT Libraries.
Today, data science is a form of power. It has been used to expose injustice, improve health outcomes, and topple governments. But it has also been used to discriminate, police, and surveil. This potential for good, on the one hand, and harm, on the other, makes it essential to ask: Data science by whom? Data science for whom? Data science with whose interests in mind? The narratives around big data and data science are overwhelmingly white, male, and techno-heroic. In Data Feminism, Catherine D'Ignazio and Lauren Klein present a new way of thinking about data science and data ethics—one that is informed by intersectional feminist thought.
Illustrating data feminism in action, D'Ignazio and Klein show how challenges to the male/female binary can help challenge other hierarchical (and empirically wrong) classification systems. They explain how, for example, an understanding of emotion can expand our ideas about effective data visualization, and how the concept of invisible labor can expose the significant human efforts required by our automated systems. And they show why the data never, ever “speak for themselves.”
Data Feminism offers strategies for data scientists seeking to learn how feminism can help them work toward justice, and for feminists who want to focus their efforts on the growing field of data science. But Data Feminism is about much more than gender. It is about power, about who has it and who doesn't, and about how those differentials of power can be challenged and changed.
Talc formation via silica‐metasomatism of ultramafic rocks is believed to play key roles in subduction zone processes. Yet, the conditions of talc formation remain poorly constrained. We used ...thermodynamic reaction‐path models to assess the formation of talc at the slab‐mantle interface and show that it is restricted to a limited set of pressure–temperature conditions, protolith, and fluid compositions. In contrast, our models predict that chlorite formation is ubiquitous at conditions relevant to the slab‐mantle interface of subduction zones. The scarcity of talc and abundance of chlorite is evident in the rock record of exhumed subduction zone terranes. Talc formation during Si‐metasomatism may thus play a more limited role in volatile cycling, strain localization, and in controlling the decoupling‐coupling transition of the plate interface. Conversely, the observed and predicted ubiquity of chlorite corroborates its prominent role in slab‐mantle interface processes that previous studies attributed to talc.
Plain Language Summary
In subduction zones, talc can form during chemical reactions of mantle rocks with silica‐enriched fluids at the interface between descending oceanic plates and the overriding mantle. Its formation and distribution in subduction zones are believed to affect the volatile budget, rheological properties, and the down‐dip limit of the decoupling of the slab‐mantle interface. Therefore, illuminating the conditions that facilitate talc formation at high pressure‐temperature conditions is key in assessing its roles in fundamental subduction zone processes. Using thermodynamic reaction‐path models, we show that the formation of talc at the slab‐mantle interface is restricted to a limited set of environmental conditions, because its formation is highly sensitive to the compositions of the mantle rocks and reactant fluids. Contrary to common belief, talc is unlikely to form in high abundance in ultramafic rocks metasomatized by Si‐rich slab‐derived fluids. Rather, our models predict the ubiquitous formation of chlorite along with other silicate minerals during Si‐metasomatism due to the competing effects from other dissolved components that favor their formation over talc. This study calls into question the importance of talc during Si‐metasomatism in subduction zones but highlights the more predominant role of chlorite.
Key Points
Limited talc formation by Si‐metasomatism of ultramafic rocks in subduction zones
Chlorite formation is likely pervasive at the slab‐mantle interface
Preferential formation of chlorite has wide‐ranging chemical and physical implications for subduction zone processes
This essay offers seven intersectional feminist principles for equitable and actionable COVID-19 data, drawing from the authors' prior work on data feminism. Our book, Data Feminism (D'Ignazio and ...Klein, 2020), offers seven principles which suggest possible points of entry for challenging and changing power imbalances in data science. In this essay, we offer seven sets of examples, one inspired by each of our principles, for both identifying existing power imbalances with respect to the impact of the novel coronavirus and its response, and for beginning the work of change.
COVID-19, caused by SARS-CoV-2, lacks effective therapeutics. Additionally, no antiviral drugs or vaccines were developed against the closely related coronavirus, SARS-CoV-1 or MERS-CoV, despite ...previous zoonotic outbreaks. To identify starting points for such therapeutics, we performed a large-scale screen of electrophile and non-covalent fragments through a combined mass spectrometry and X-ray approach against the SARS-CoV-2 main protease, one of two cysteine viral proteases essential for viral replication. Our crystallographic screen identified 71 hits that span the entire active site, as well as 3 hits at the dimer interface. These structures reveal routes to rapidly develop more potent inhibitors through merging of covalent and non-covalent fragment hits; one series of low-reactivity, tractable covalent fragments were progressed to discover improved binders. These combined hits offer unprecedented structural and reactivity information for on-going structure-based drug design against SARS-CoV-2 main protease.
The promoter effect of alkali causes an increased 1-alkene selectivity, a slightly increased reaction rate, an increased growth probability of hydrocarbons and an increased resistance against ...oxidation by water. These effects are interpreted by a novel hypothesis of the reaction mechanism of F.T.-synthesis.
▪
The promoter effect of alkali on Fischer-Tropsch iron catalysts causes an increased 1-alkene selectivity, a slightly increased reaction rate, an increased growth probability of hydrocarbon chains and also an increased resistance against oxidation of iron by the reaction product water. Experiments are presented which show that for cobalt catalysts alkali addition also leads to increased 1-alkene selectivity. However, the reaction rate is markedly reduced.
The effect on the 1-alkene selectivity is without doubt due to increased adsorption strength of carbon monoxide causing an enhanced displacement of 1-alkenes while the propensity towards hydrogenation is hardly reduced. For iron catalysts the 1-alkene selectivity increases in the turn of Li, Na, K, Cs. With respect to the bimodal Anderson-Schulz-Flory (ASF) distribution the strong effect on the growth probability
α
2 is independent of the nature of the alkali cation while the fraction
f
2 of the distribution that is characterized by
α
2 increases in the turn Li, Na, K, and Cs.
These strong promoter effects are interpreted on the basis of a novel mechanism of Fischer-Tropsch synthesis whereby the alkali cation takes part in the catalytic circle.
Finally an analogy of the promoter effect of alkali on iron for the ammonia synthesis and the Fischer-Tropsch synthesis is suggested.
Functional connectivity analyses of resting-state fMRI data are rapidly emerging as highly efficient and powerful tools for in vivo mapping of functional networks in the brain, referred to as ...intrinsic connectivity networks (ICNs). Despite a burgeoning literature, researchers continue to struggle with the challenge of defining computationally efficient and reliable approaches for identifying and characterizing ICNs. Independent component analysis (ICA) has emerged as a powerful tool for exploring ICNs in both healthy and clinical populations. In particular, temporal concatenation group ICA (TC-GICA) coupled with a back-reconstruction step produces participant-level resting state functional connectivity maps for each group-level component. The present work systematically evaluated the test–retest reliability of TC-GICA derived RSFC measures over the short-term (<45 min) and long-term (5–16 months). Additionally, to investigate the degree to which the components revealed by TC-GICA are detectable via single-session ICA, we investigated the reproducibility of TC-GICA findings. First, we found moderate-to-high short- and long-term test–retest reliability for ICNs derived by combining TC-GICA and dual regression. Exceptions to this finding were limited to physiological- and imaging-related artifacts. Second, our reproducibility analyses revealed notable limitations for template matching procedures to accurately detect TC-GICA based components at the individual scan level. Third, we found that TC-GICA component's reliability and reproducibility ranks are highly consistent. In summary, TC-GICA combined with dual regression is an effective and reliable approach to exploratory analyses of resting state fMRI data.
The human brain is a complex dynamic system capable of generating a multitude of oscillatory waves in support of brain function. Using fMRI, we examined the amplitude of spontaneous low-frequency ...oscillations (LFO) observed in the human resting brain and the test–retest reliability of relevant amplitude measures. We confirmed prior reports that gray matter exhibits higher LFO amplitude than white matter. Within gray matter, the largest amplitudes appeared along mid-brain structures associated with the “default-mode” network. Additionally, we found that high-amplitude LFO activity in specific brain regions was reliable across time. Furthermore, parcellation-based results revealed significant and highly reliable ranking orders of LFO amplitudes among anatomical parcellation units. Detailed examination of individual low frequency bands showed distinct spatial profiles. Intriguingly, LFO amplitudes in the slow-4 (0.027–0.073 Hz) band, as defined by Buzsáki et al., were most robust in the basal ganglia, as has been found in spontaneous electrophysiological recordings in the awake rat. These results suggest that amplitude measures of LFO can contribute to further between-group characterization of existing and future “resting-state” fMRI datasets.
Diagnostics are essential for controlling the pandemic. Identifying a reliable and fast diagnostic device is needed for effective testing. We assessed performance and ease-of-use of the Abbott PanBio ...antigen-detecting rapid diagnostic test (Ag-RDT).
This prospective, multi-centre diagnostic accuracy study enrolled at two sites in Germany. Following routine testing with reverse-transcriptase polymerase chain reaction (RT-PCR), a second study-exclusive swab was performed for Ag-RDT testing. Routine swabs were nasopharyngeal (NP) or combined NP/oropharyngeal (OP) whereas the study-exclusive swabs were NP. To evaluate performance, sensitivity and specificity were assessed overall and in predefined sub-analyses accordingly to cycle-threshold values, days after symptom onset, disease severity and study site. Additionally, an ease-of-use assessment (EoU) and System Usability Scale (SUS) were performed.
1108 participants were enrolled between Sept 28 and Oct 30, 2020. Of these, 106 (9.6%) were PCR-positive. The Abbott PanBio detected 92/106 PCR-positive participants with a sensitivity of 86.8% (95% CI: 79.0% - 92.0%) and a specificity of 99.9% (95% CI: 99.4%-100%). The sub-analyses indicated that sensitivity was 95.8% in Ct-values <25 and within the first seven days from symptom onset. The test was characterized as easy to use (SUS: 86/100) and considered suitable for point-of-care settings.
The Abbott PanBio Ag-RDT performs well for SARS-CoV-2 testing in this large manufacturer independent study, confirming its WHO recommendation for Emergency Use in settings with limited resources.
Understanding brain dysfunction in sepsis Sonneville, Romain; Verdonk, Franck; Rauturier, Camille ...
Annals of intensive care,
05/2013, Letnik:
3, Številka:
1
Journal Article
Recenzirano
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Sepsis often is characterized by an acute brain dysfunction, which is associated with increased morbidity and mortality. Its pathophysiology is highly complex, resulting from both inflammatory and ...noninflammatory processes, which may induce significant alterations in vulnerable areas of the brain. Important mechanisms include excessive microglial activation, impaired cerebral perfusion, blood–brain-barrier dysfunction, and altered neurotransmission. Systemic insults, such as prolonged inflammation, severe hypoxemia, and persistent hyperglycemia also may contribute to aggravate sepsis-induced brain dysfunction or injury. The diagnosis of brain dysfunction in sepsis relies essentially on neurological examination and neurological tests, such as EEG and neuroimaging. A brain MRI should be considered in case of persistent brain dysfunction after control of sepsis and exclusion of major confounding factors. Recent MRI studies suggest that septic shock can be associated with acute cerebrovascular lesions and white matter abnormalities. Currently, the management of brain dysfunction mainly consists of control of sepsis and prevention of all aggravating factors, including metabolic disturbances, drug overdoses, anticholinergic medications, withdrawal syndromes, and Wernicke’s encephalopathy. Modulation of microglial activation, prevention of blood–brain-barrier alterations, and use of antioxidants represent relevant therapeutic targets that may impact significantly on neurologic outcomes. In the future, investigations in patients with sepsis should be undertaken to reduce the duration of brain dysfunction and to study the impact of this reduction on important health outcomes, including functional and cognitive status in survivors.
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