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Does media choice cause polarization, or merely reflect it? We investigate a critical aspect of this puzzle: How partisan media contribute to attitude polarization among different groups of media consumers. We implement a new experimental design, called the Preference-Incorporating Choice and Assignment (PICA) design, that incorporates both free choice and forced exposure. We estimate jointly the degree of polarization caused by selective exposure and the persuasive effect of partisan media. Our design also enables us to conduct sensitivity analyses accounting for discrepancies between stated preferences and actual choice, a potential source of bias ignored in previous studies using similar designs. We find that partisan media can polarize both its regular consumers and inadvertent audiences who would otherwise not consume it, but ideologically opposing media potentially also can ameliorate the existing polarization between consumers. Taken together, these results deepen our understanding of when and how media polarize individuals.
The purpose of this work was to develop accurate calibration standards which were fully characterized in terms of uniformity and concentration using fundamental measuring methods. Three similar sets of vacuum deposits were commercially made, each set containing the single deposits CuS, KCl, CaF2, Cr, Fe, Cu, RbNO3, SrF2, MoO3 , BaF2, and Pb. Thickness variations in each deposit were measured with PIXEA (proton induced x-ray excitation analysis) measurements taken at 6 to 8 positions along the deposit diameters. Relative elemental concentrations on corresponding deposits from each set were measured using multiple XRF intercomparisons. One set of deposits was destructively analyzed at the National Bureau of Standards with isotope dilution thermal ionization mass spectrometry (IDMS) in order to calibrate the remaining sets of vacuum deposits. The calibrated deposits were compared with standards from two commercial sources. For seven elements heavier than chlorine there was an average deviation of 13.5% between the calibrated deposits and the commercial standards. Disagreements as large as 15% were observed between standards from the two commercial suppliers.
The objective was to compare the performance of the updated Charlson comorbidity index (uCCI) and classical CCI (cCCI) in predicting 30-day mortality in patients with Staphylococcus aureus bacteraemia (SAB). All cases of SAB in patients aged ⩾14 years identified at the Microbiology Unit were included prospectively and followed. Comorbidity was evaluated using the cCCI and uCCI. Relevant variables associated with SAB-related mortality, along with cCCI or uCCI scores, were entered into multivariate logistic regression models. Global model fit, model calibration and predictive validity of each model were evaluated and compared. In total, 257 episodes of SAB in 239 patients were included (mean age 74 years; 65% were male). The mean cCCI and uCCI scores were 3.6 (standard deviation, 2.4) and 2.9 (2.3), respectively; 161 (63%) cases had cCCI score ⩾3 and 89 (35%) cases had uCCI score ⩾4. Sixty-five (25%) patients died within 30 days. The cCCI score was not related to mortality in any model, but uCCI score ⩾4 was an independent factor of 30-day mortality (odds ratio, 1.98; 95% confidence interval, 1.05–3.74). The uCCI is a more up-to-date, refined and parsimonious prognostic mortality score than the cCCI; it may thus serve better than the latter in the identification of patients with SAB with worse prognoses.
Although associations between various somatic diseases and depression are well established, findings concerning the role of gender and anxiety disorders for these associations remain fragmented and partly inconsistent. Combining data from three large-scaled epidemiological studies in primary care, we aim to investigate interactions of somatic diseases with gender and anxiety disorders in the association with depression.
Self-reported depression according to the International Classification of Diseases, Tenth Edition (ICD-10) was assessed in n = 83 737 patients from three independent studies [DETECT (Diabetes Cardiovascular Risk Evaluation: Targets and Essential Data for Commitment of Treatment), Depression-2000 and Generalized Anxiety and Depression in Primary Care (GAD-P)] using the Depression Screening Questionnaire (DSQ). Diagnoses of depression, anxiety disorders and somatic diseases were obtained from treating physicians via standardised clinical appraisal forms.
In logistic regressions, adjusted for gender, age group and study, each somatic disease except for arterial hypertension and endocrine diseases was associated with self-reported depression (odds ratio, OR 1.3–2.6) and each somatic disease was associated with physician-diagnosed depression (OR 1.1–2.4). Most of these associations remained significant after additional adjustment for anxiety disorders and other somatic diseases. The associations with depression increased with a higher number of somatic diseases. Cardiovascular diseases (OR 0.8), diabetes mellitus (OR 0.8) and neurological diseases (OR 0.8) interacted with gender in the association with self-reported depression, while endocrine diseases (OR 0.8) interacted with gender in the association with physician-diagnosed depression. That is, the associations between respective somatic diseases and depression were less pronounced in females v. males. Moreover, cardiovascular diseases (OR 0.7), arterial hypertension (OR 0.8), gastrointestinal diseases (OR 0.7) and neurological diseases (OR 0.6) interacted with anxiety disorders in the association with self-reported depression, and each somatic disease interacted with anxiety disorders in the association with physician-diagnosed depression (OR 0.6–0.8). That is, the associations between respective somatic diseases and depression were less pronounced in patients with v. without anxiety disorders; arterial hypertension was negatively associated with self-reported depression only in patients with anxiety disorders, but not in patients without anxiety disorders.
A range of somatic diseases as well as anxiety disorders are linked to depression – and especially patients with co-/multi-morbidity are affected. However, interactions with gender and anxiety disorders are noteworthy and of relevance to potentially improve recognition and treatment of depression by physicians. Somatic diseases are associated more strongly with depression in males v. females as well as in patients without v. with anxiety disorders, primarily because women and patients with anxiety disorders per se are characterised by considerably increased depression prevalence that only marginally changes in the presence of somatic comorbidity.
Shiga toxin-producing Escherichia coli (STEC) is a significant cause of gastrointestinal infection and the haemolytic-uremic syndrome (HUS). STEC outbreaks are commonly associated with food but animal contact is increasingly being implicated in its transmission. We report an outbreak of STEC affecting young infants at a nursery in a rural community (three HUS cases, one definite case, one probable case, three possible cases and five carriers, based on the combination of clinical, epidemiological and laboratory data) identified using culture-based and molecular techniques. The investigation identified repeated animal contact (animal farming and petting) as a likely source of STEC introduction followed by horizontal transmission. Whole genome sequencing (WGS) was used for real-time investigation of the incident and revealed a unique strain of STEC O26:H11 carrying stx2a and intimin. Following a public health intervention, no additional cases have occurred. This is the first STEC outbreak reported from Israel. WGS proved as a useful tool for rapid laboratory characterization and typing of the outbreak strain and informed the public health response at an early stage of this unusual outbreak.
This is a status report on a continuing program using the Hubble Space Telescope (HST) Wide–Field Camera (WFC) to probe the stellar population of the Galactic bulge to fainter magnitudes. We seek the mean age of the stars and the initial mass function (IMF). Galactic bulge stars offer the only opportunity to investigate the IMF of a super metal–rich population. They are 100 times closer than the next nearest sample.
Laboratory reconnection experiments dedicated to problems of space and astrophysics are briefly reviewed with the purpose of demonstrating that such experiments can provide important insights of considerable value to the development of reconnection theory. Moreover, many of these insights are of a kind not likely to be perceived either when working directly with space observations or while pursuing a course of pure theoretical reasoning without reference to laboratory results.
Objectives: The present study examined differences in neurocognitive outcomes among non-Hispanic Black and White stroke survivors using the NIH Toolbox-Cognition Battery (NIHTB-CB), and investigated the roles of healthcare variables in explaining racial differences in neurocognitive outcomes post-stroke. Methods: One-hundred seventy adults (91 Black; 79 White), who participated in a multisite study were included (age: M=56.4; SD=12.6; education: M=13.7; SD=2.5; 50% male; years post-stroke: 1–18; stroke type: 72% ischemic, 28% hemorrhagic). Neurocognitive function was assessed with the NIHTB-CB, using demographically corrected norms. Participants completed measures of socio-demographic characteristics, health literacy, and healthcare use and access. Stroke severity was assessed with the Modified Rankin Scale. Results: An independent samples t test indicated Blacks showed more neurocognitive impairment (NIHTB-CB Fluid Composite T-score: M=37.63; SD=11.67) than Whites (Fluid T-score: M=42.59, SD=11.54; p=.006). This difference remained significant after adjusting for reading level (NIHTB-CB Oral Reading), and when stratified by stroke severity. Blacks also scored lower on health literacy, reported differences in insurance type, and reported decreased confidence in the doctors treating them. Multivariable models adjusting for reading level and injury severity showed that health literacy and insurance type were statistically significant predictors of the Fluid cognitive composite (p<.001 and p=.02, respectively) and significantly mediated racial differences on neurocognitive impairment. Conclusions: We replicated prior work showing that Blacks are at increased risk for poorer neurocognitive outcomes post-stroke than Whites. Health literacy and insurance type might be important modifiable factors influencing these differences. (JINS, 2017, 23, 640–652)
Increasingly, the evidence from optical and infra–red wavebands suggests that the difference between Seyfert 1 and Seyfert 2 nuclei is due largely to orientation effects rather than intrinsic differences between the two classes, but the evidence from radio observations has been less clear–cut. We have observed the CfA Seyfert Sample at 8.4 GHz using the VLA in A– and C–configurations. At this frequency our A–array maps have a resolution of 0.25″ – much higher than those achieved in previous surveys – whilst the 3″ C–array beam is ideal for measuring the total radio flux of the active nucleus. The 1–sigma noise in both sets of observations was 70 μJy.
We have observed a complete sample of 21 nearby (D < 70h−1Mpc) Fanaroff & Riley Type I galaxies with HST/WFPC2 and detected dust disks and lanes in 19 of them. The radio jets are roughly perpendicular to the dust which is used to constrain the Doppler boosting factors of the radio jet and cores. The VLBA core flux correlates with the central Hα+[NII] flux which might indicate that the VLBA core is dominated by an isotropic component. Twelve galaxies show nuclear optical sources. We discuss various possible origins for this emission.
Since the date of the 1935 Paris meeting two total eclipses have been successfully observed. Throughout the long path crossing Siberia and Japan the weather on June 19, 1936 on the whole about lived up to predictions. On account of widely scattered clouds neighbouring expeditions had quite different luck with the weather. In contrast, the June 8, 1937 eclipse was seen throughout the whole track under universally clear skies, which is all the more surprising for the reason that eclipse expeditions to the tropics usually fare badly with the weather. Stewart and Stokley in a ship at sea were able to observe the eclipse with a measured duration of 7 min. 6 sec., the longest period of totality in 1200 years.
(i) 1936, June 19. The Eclipse Committees of Japan and the U.S.S.R. have been making preliminary meteorological studies of the weather conditions along the belt of totality in their respective countries. The Japanese Committee report (Bulldin, Kwasan Observatory, 283, 1934) that, while at the extreme east and west of their totality zone the weather prospects are unfavourable, for the central part, along the north-east coast of the island of Hokkaido, from Esasi to Monpetu and in a region round Syari the weather conditions are as good as in the best seasons of Tokyo and Kyoto in an ordinary year. A pamphlet giving all information is being prepared and will shortly be circulated in astronomical circles, but it may be mentioned that Monpetu and Syari are accessible by rail from the port of Otaru. There is electric current, 100 V, A.c., labour is readily available and accommodation will be possible for small parties.
Le présent rapport ressemblera peu à ceux présentés aux précédentes Assemblées Générales de l’Union; d’abord en raison des prescriptions du Comité Exécutif concernant la limitation du texte, la suppression des références bibliographiques et la latitude laissée au Président dans la conception même du Rapport; ensuite parce qu’il est apparu que la Commission 9 avait un rôle et une position assez différents de ceux de la plupart des autres Commissions et que l’un des points auxquels il convenait de s’attacher était précisément le re-modelage de son activité.
Toutefois, un certain nombre de membres de l’Union ayant bien voulu résumer l’activité de leurs Institutions ou de leurs pays dans le domaine de l’instrumentation astronomique, leurs contributions trouveront place dans le présent Rapport et fourniront ainsi aux membres de l’Union une information non exhaustive mais cependant des plus utiles, en attendant que soit mise au point une nouvelle forme de documentation.
Enfin, l’un des groupes de travail de la Commission - sur les Tubes à images - ayant poursuivi son travail de coordination et d’information comme par le passé, un rapport spécial sur son activité figurera à la suite du Rapport Général de la Commission 9.
At the Paris congress in 1935, Messrs Dittrich, Brasch and Pogo had proposed that Commission 5 should undertake the publication of classical works of astronomy (such as Ptolemy’s Almagest, the works of Copernicus, etc.) which were untranslated or for other reasons difficult of access. The commission decided to form a sub-commission, consisting of Mr Stroobant and the gentlemen named above, to study this question, especially the means for its realization. Mr Stroobant had announced his desire to take this work in hand personally. Prof. Stroobant, however, having deceased in July 1936, and his health having been deficient during several months in advance, the sub-commission has not been able to continue its work. This is a question that ought to be taken up at the Stockholm meeting.
La Commission n’a pas été informée de travaux particuliers importants concernant les matières d’optique. Il convient toutefois de mentionner dans cet ordre d’idées les résultats intéressants obtenus par application d’une pellicule d’aluminium comme surface réfléchissante, pour les miroirs astronomiques.
Le dépôt est fait par évaporation dans le vide et s’applique immédiatement aux miroirs en verre de petites dimensions. Pour les grandes surfaces, l’installation capable de résister à la pression atmosphérique peut présenter de grandes difficultés. Cependant, il a été possible de traiter ainsi, par exemple, le miroir de 90 cm. de diamètre de l’Observatoire de Lick. Plusieurs observatoires américains ont mis en service des miroirs aluminisés.
An obesity paradox has been proposed in many conditions including HIV. Studies conducted to investigate obesity and its effect on HIV disease progression have been inconclusive and are lacking for African settings. This study investigated the relationship between overweight/obesity (BMI≥25 kg/m2) and HIV disease progression in HIV+ asymptomatic adults not on antiretroviral treatment (ART) in Botswana over 18 months. A cohort study in asymptomatic, ART-naïve, HIV+ adults included 217 participants, 139 with BMI of 18·0–24·9 kg/m2 and seventy-eight participants with BMI≥25 kg/m2. The primary outcome was time to event (≥25 % decrease in cluster of differentiation 4 (CD4) cell count) during 18 months of follow-up; secondary outcomes were time to event of CD4 cell count<250 cells/µl and AIDS-defining conditions. Proportional survival hazard models were used to compare hazard ratios (HR) on time to events of HIV disease progression over 18 months. Higher baseline BMI was associated with significantly lower risk of an AIDS-defining condition during the follow-up (HR 0·218; 95 % CI 0·068, 0·701; P=0·011). Higher fat mass at baseline was also significantly associated with decreased risk of AIDS-defining conditions during the follow-up (HR 0·855; 95 % CI 0·741, 0·987; P=0·033) and the combined outcome of having CD4 cell count≤250/µl and AIDS-defining conditions, whichever occurred earlier (HR 0·918; 95 % CI 0·847, 0·994; P=0·036). All models were adjusted for covariates. Higher BMI and fat mass among the HIV-infected, ART-naïve participants were associated with slower disease progression. Mechanistic research is needed to evaluate the association between BMI, fat mass and HIV disease progression.
In orthodox dynamo theory (Stix, 1976), the two basic processes, generation of toroidal from poloidal field and conversion of toroidal into reversed poloidal field, are both located in the high β regime convection zone. Generation requires that regime, since its function demands it be driven by mechanical forces. But the function and therefore the operating requirements of conversion are entirely different, and there seems to be no à priori reason, other than historical tradition coupled with failure to recognize those differences, for the assumption that conversion must also operate there. Conversion transforms the topological structure of generated flux by altering the field line connectivity, so that the principal task performed is reconnection. Reconnection is a spontaneous process which must compress and accelerate plasma if any is present. Obviously it must perform much more work in the high β convection zone than in the low β solar atmosphere. It seems natural, therefore, to expect the reconnection aspect of conversion to be located there, where the least work needs to be performed. To transfer the generated flux there, we may add to conversion another spontaneous process: eruption of bipolar structure (Parker, 1955). To transfer the reconnected flux back down, we add to generation another mechanically driven process called topological pumping (Drobyshevski and Yuferev, 1974). Topological pumping depends on the diamagnetic effect of eddy-motion (Wiess, 1966), the kind possessed by supergranulation: 3-dimensional arrangement of isolated rising plumes, surrounded by a continuous network of descending sheet-like flow. In the two-level dynamo presented here, conversion may be observed directly, since we expect it to express itself in terms of all forms of solar activity: sunspots, flares, faculae, filaments, coronal structures including coronal holes, etc., and their organization and evolution in a “solar meteorology”. It is clearly important to investigate a model that thus unites the two disciplines of solar activity and dynamo theory. Each strengthens the other and brings a greater unity to solar physics.
A search of several thousand plates in the Lowell Observatory collection yielded 28 groups of plates on which the positions of well-defined transient bright spots (often assumed to be clouds) could be followed on a nearly daily basis. These groups of plates were from 15 different oppositions of Mars, starting from 1907 and ending with 1958. All but two of these spanned four nights or more, and the maximum interval covered was thirty nights. Whether they appeared to show motion or not, the successive positions and shapes of all apparently associated bright spots or clouds were plotted on Mercator projections with the use of a projection plate reader especially designed at the Planetary Research Center for planet image studies of this kind. Clouds near the limb were avoided.
The 28 groups of plates yielded 95 cloud histories. More than half appeared to be relatively stationary. Others showed definite motion well in excess of observational error but sometimes followed paths that partly doubled back upon themselves. The mean velocity for non-stationary clouds was found to be 5.6 km per hour, and the most commonly occurring direction of motion was eastward, particularly at high latitudes. The range of velocities found by this mapping procedure is nearly an order of magnitude smaller than values that have been estimated earlier by others from visual observations. These earlier observations are evidently in error, unless there exist clouds at high elevation, visible only on the limb, that can move much faster than those that were mapped from this photographic survey. More clouds were found in the northern hemisphere than in the southern, and there seemed to be an avoidance of the relatively darker areas of the Martian surface. Certain regions seem to be more favored than others. A few recurrences at identical positions suggest the existence of related topographic features.