ABSTRACT
Chemically peculiar (CP) stars of the upper main sequence are characterized by specific anomalies in the photospheric abundances of some chemical elements. The group of CP2 stars, which ...encompasses classical Ap and Bp stars, exhibits strictly periodic light, spectral, and spectropolarimetric variations that can be adequately explained by the model of a rigidly rotating star with persistent surface structures and a stable global magnetic field. Using observations from the Kepler K2 mission, we find that the B9pSi star HD 174356 displays a light curve variable in both amplitude and shape, which is not expected in a CP2 star. Employing archival and new photometric and spectroscopic observations, we carry out a detailed abundance analysis of HD 174356 and discuss its photometric and astrophysical properties in detail. We employ phenomenological modelling to decompose the light curve and the observed radial velocity variability. Our abundance analysis confirms that HD 174356 is a silicon-type CP2 star. No magnetic field stronger than 110 G was found. The star’s light curve can be interpreted as the sum of two independent strictly periodic signals with $P_1=4{_{.}^{\rm d}}043\, 55(5)$ and $P_2=2{_{.}^{\rm d}}111\, 69(3)$. The periods have remained stable over 17 yr of observations. In all spectra, HD 174356 appears to be single-lined. From the simulation of the variability characteristics and investigation of stars in the close angular vicinity, we put forth the hypothesis that the peculiar light variability of HD 174356 arises in a single star and is caused by rotational modulation due to surface abundance patches (P1) and g-mode pulsation (P2).
American Democracy and Voter Suppression Fraga, Luis Ricardo; Ramírez, Ricardo; Fraga, Bernard L.
The Annals of the American Academy of Political and Social Science,
07/2023, Volume:
708, Issue:
1
Journal Article
Peer reviewed
Open access
We review the history, magnitude, and scope of voter suppression in the United States., showing that, when it is attempted, it targets the voting rights of a disfavored group. We argue that this is ...an important weakness of American democracy and that current efforts at voter suppression focus on states with major demographic shifts that are seen by some to be threatening. We then discuss the consequences of recent decisions by the Supreme Court to weaken key elements of the Voting Rights Act, arguing that a weakened Voting Rights Act has led to a resurgence of voter suppression in some states and that those same states often see a rise in countermobilization efforts aimed at encouraging targeted communities to register and vote. An undeniable impact of current attempts at voter suppression, we argue, is that it signals to certain communities that their participation in elections is not wanted.
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Voter identification (ID) laws have sparked concerns of vote suppression, but existing evidence relies on aggregate analyses or survey self-reports. We leverage unique information from Texas, where ...registrants without ID filed “reasonable impediment declarations” (RIDs) before voting. Linking 16,000 RID forms to the Texas voter file, we provide the first direct documentation of the traits of voters who would be stopped from voting under strict identification laws. Our preregistered analysis finds registrants voting without ID in 2016 were disproportionately Black and Latinx when compared to voters voting with ID. Examining voters’ stated reasons for not providing ID, we find socioeconomic hardships are not the most commonly cited impediment, but voters with hardships were less likely to vote in a strict-ID election than those who previously had identification. Our findings indicate that strict identification laws will stop a disproportionately minority, otherwise-willing set of registered voters from voting.
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We determined the activity of glyceroneogenesis from 2-14C-pyruvate, the phosphoenolpyruvate carboxykinase activity, 2-14C-pyruvate oxidation and total lipid levels in the hepatopancreas of the crab ...Neohelice granulata fed with a carbohydrate-rich (HC) diet or a high-protein (HP) diet and then subjected to 5weeks of starvation, in summer and winter, to determine whether the seasonal adjustments of lipid metabolism to food scarcity are modulated by the composition of the diet previously given to the crabs. The results demonstrated that glyceroneogenesis is an active pathway in N. granulata hepatopancreas, and is regulated by seasonal variations, diet composition and starvation. This study showed that in summer the increase in the hepatopancreas glyceroneogenesis activity is among the strategies used by N. granulata fed an HP diet, to maintain the triglyceride/fatty acid cycle during starvation, a normal condition in the biological cycle of this crab. However, the administration of an HC diet reduced the glyceroneogenesis capacity in response to starvation in summer. In winter, the decrease in the glyceroneogenesis capacity in both fed (HP and HC diets) and starved crabs seems to be a strategy to reduce energy consumption and/or requirement. In contrast to the summer results, the incorporation of 2-14C-pyruvate into 14CO2 was markedly higher in both diet (HC and HP) groups and in starved crabs during the winter. Four decades after the first study describing the glyceroneogenesis pathway in rat white adipose tissue, this pathway is evidenced for the first time in a crustacean.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Do parties face an electoral penalty when they nominate candidates of colour? We employ a regression discontinuity design using state legislative election data from 2018, 2019, and 2020 to isolate ...the effect of nominating a candidate of colour on a party's general election performance. Utilising this approach with real-world data heightens external validity relative to existing racial penalty studies, largely supported by surveys and experiments. We find no evidence that candidates of colour are disadvantaged in state legislative general elections relative to narrowly nominated white candidates from the same party. These findings challenge the leading explanations for the underrepresentation of racial/ethnic minority groups, with implications for candidate selection across the United States.
Racial/ethnic minorities and women continue to be underrepresented in public office in the United States. Here, we evaluate the role of general election political party support for women and ...minorities in structuring these inequalities, as a key part of general election success is support from party networks. With detailed data on party support and the demographics of congressional candidates, we use two difference-in-differences strategies to leverage within-district and candidate-constant change over time. Thus, we are able to separate the effect of race/ethnicity and gender from other factors we demonstrate to be associated with party support. We find that, all else equal, Democratic and Republican minority nominees do not receive less support than their white counterparts. We also find that white women receive more party support from Democrats than Democratic men or minority women in the general election and that this support is more responsive to changes in electoral competitiveness. These findings suggest that party elites may provide additional support to candidates from underrepresented groups in the general election to broaden their appeal to voters.
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Using the The SOuthern Astrophysical Research (SOAR) 4.1-m telescope, we report on the discovery of low amplitude pulsations for three stars previously reported as not-observed-to-vary (NOV) by ...Mukadam et al. and Mullally et al., which are inside the ZZ Ceti instability strip. With the two pulsators discovered by Castanheira et al., we have now found variability in a total of five stars previously reported as NOVs. We also report the variability of eight new pulsating stars, not previously observed, bringing the total number of known ZZ Ceti stars to 148. In addition, we lowered the detection limit for 10 NOVs located near the edges of the ZZ Ceti instability strip. Our results are consistent with a pure mass-dependent ZZ Ceti instability strip.
► The reduction of Cr(VI) to Cr(III) was characterized by multiple techniques. ► Use of peat or its fraction as adsorbents for the reduction/remotion of Cr(VI). ► Removal capacity of chromium was ...increased at lower pH. ► Removal efficiencies of chromium increased with the reduction of Cr(VI) to Cr(III).
The reduction of Cr(VI) to Cr(III) in aqueous solution, and the subsequent removal of Cr(III) using in natura peat or its humin fraction, was characterized by electron paramagnetic resonance (EPR), ultraviolet–visible (UV–Vis) spectroscopy and X-ray photoelectron (XPS) spectroscopy. EPR spectroscopy g-factors ranging from 2.0029 to 2.0030 indicated the presence of organic free radicals (OFR) associated with carbon atoms. The spin densities of the samples increased with pH in the range pH 2.0–pH 6.0. An XPS spectroscopy peak at 579.0eV was attributed to Cr(VI), and peaks at 576.8eV and 677.3eV to two different chemical forms of Cr(III). Removal of chromium increased with the reduction of Cr(VI) to Cr(III), and removal rates after 50h were 13% (peat) and 15% (humin) at pH 6.0, and 70% (peat) and 80% (humin) at pH 2.0. The greater efficiency of the humin fraction in the reduction/removal process is discussed in terms of the chemical structures of these materials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Variations in the pulsation arrival time of five independent pulsation frequencies of the DB white dwarf EC 20058-5234 individually imitate the effects of reflex motion induced by a planet or ...companion but are inconsistent when considered in unison. The pulsation frequencies vary periodically in a 12.9 year cycle and undergo secular changes that are inconsistent with simple neutrino plus photon-cooling models. The magnitude of the periodic and secular variations increases with the period of the pulsations, possibly hinting that the corresponding physical mechanism is located near the surface of the star. The phase of the periodic variations appears coupled to the sign of the secular variations. The standards for pulsation-timing-based detection of planetary companions around pulsating white dwarfs, and possibly other variables such as subdwarf B stars, should be re-evaluated. The physical mechanism responsible for this surprising result may involve a redistribution of angular momentum or a magnetic cycle. Additionally, variations in a supposed combination frequency are shown to match the sum of the variations of the parent frequencies to remarkable precision, an expected but unprecedented confirmation of theoretical predictions.
The Current Population Survey (CPS) is a key source of information on who votes. Turnout estimates derived from the CPS are often cited in academic research on participation, widely used in the ...calibration of surveys, and central to ongoing legal and policy debates over the protection of voting rights in the United States. We compare CPS estimates to official voter turnout records from 2008–18 and document consistent, significant discrepancies that call into question the reliability of CPS turnout statistics. Specifically, the CPS overestimates black and Hispanic turnout relative to non-Hispanic whites, whether relying on turnout rates as a share of eligible citizens or the racial/ethnic composition of the voting population. Sampling error and commonly used adjustments to CPS estimates do not account for or correct this bias, and thus academics and policy makers should use discretion when judging recent shifts in voter turnout with survey data.
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