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Most research on the causes of women's underrepresentation examines one of two stages of the political pipeline: the development of nascent political ambition or specific aspects of the campaign and election process. In this article, we make a different kind of contribution. We build on the growing literature on gender, psychology, and representation to provide an analysis of what kinds of men and women make it through the political pipeline at each stage. This allows us to draw some conclusions about the ways in which the overall process is similar and different for women and men. Using surveys of the general U.S. population (N = 1,939) and elected municipal officials such as mayors and city councilors (N = 2,354) that measure the distribution of Big Five personality traits, we find that roughly the same types of men and women have nascent political ambition; there is just an intercept shift for sex. In contrast, male and female elected officials have different personality profiles. These differences do not reflect underlying distributions in the general population or the population of political aspirants. In short, our data suggest that socialization into political ambition is similar for men and women, but campaign and election processes are not.
Good education requires student experiences that deliver lessons about practice as well as theory and that encourage students to work for the public good—especially in the operation of democratic institutions (Dewey 1923; Dewy 1938). We report on an evaluation of the pedagogical value of a research project involving 23 colleges and universities across the country. Faculty trained and supervised students who observed polling places in the 2016 General Election. Our findings indicate that this was a valuable learning experience in both the short and long terms. Students found their experiences to be valuable and reported learning generally and specifically related to course material. Postelection, they also felt more knowledgeable about election science topics, voting behavior, and research methods. Students reported interest in participating in similar research in the future, would recommend other students to do so, and expressed interest in more learning and research about the topics central to their experience. Our results suggest that participants appreciated the importance of elections and their study. Collectively, the participating students are engaged and efficacious—essential qualities of citizens in a democracy.
Introduction: Medical transport services are essential in the regionalization of trauma care. Given the limited number of designated trauma centers, transport times can be prolonged, with patient care managed by paramedics for the duration of their transfer. Pain management is a paramount component, but oligoanalgesia can occur. The primary objective of this study was to evaluate pain management practices during transport of trauma patients by air. Methods: We conducted a 12-month review of ORNGE electronic paramedic records. ORNGE is the exclusive provider of air and land transport in Ontario, Canada. Cases from 1 January 2015 to 31 December 2015 were screened. Patients were identified according to inclusion (≥18 years old requiring transportation to designated trauma center) and exclusion criteria (GCS<14; intubation; accompanied by a nurse or physician). Information was collected in a standardized, piloted data form used by a single trained data extractor. Demographics, injury description, and transportation parameters were recorded. Outcomes included pain assessment according to changes on a 10-point numeric rating scale (NRS), patterns of analgesia administration, and analgesia-related adverse events (AEs). Results were reported as mean, (standard deviation), [range], or percentage. Results: Of 600 potential records, 372 patients met our inclusion criteria with the following characteristics: age 47.0 [19-92] years; 70.4% male; 97.0% blunt injury. Duration of transport was 82.4 (46.3) minutes. Pain was initially assessed in 90.0% of patients. Overall, NRS at baseline was 4.9 (2.8). Of the 62.4% who received analgesia, NRS at baseline was 5.9 (2.5). Fentanyl was most commonly administered (78.5%) at 44.3 [25-60] mcg. NRS after the first dose of analgesia decreased by 1.1 (1.6) points. A total of 73.7% of patients received further analgesia, equal to 2.4 [1-19] additional doses. While 23.4% of patients had no change in NRS after the first dose of analgesia, subsequent doses resulted in no change in NRS in over 65% [65.4-71.3] of patients. A total of 43 AEs (6.7%) were recorded after 638 doses of analgesia, and the most common AE was nausea (39.5%). Conclusion: The majority of patients were assessed for pain. Although the first analgesia administration had minimal effect on NRS, subsequent doses appeared to have even less of an impact. AEs were infrequent.
For each particle in an aggregate of point particles in the plane, the set of points having it as closest particle is a convex polygon, and the aggregate V of such Voronoi polygons tessellates the plane. The geometric and stochastic structure of a random Voronoi polygon relative to a homogeneous Poisson process is specified.
Similarly, those points of the plane possessing the same n nearest particles constitute a convex polygon cell in the generalized Voronoi tessellation 𝒱 (n = 2, 3, ·· ·). In fact, 𝒱 = 𝒱1, but to ease exposition n always takes the values 2, 3, ···. A key geometrical lemma elucidates the geometric structure of members of 𝒱n, showing it to be simpler in one important respect than that of members of 𝒱; in that, for each such N-gon of given ‘type', there is a uniquely determined set of N generating particles. The corresponding jacobian is given, and used to derive the basic ergodic structure of 𝒱n relative to a homogeneous Poisson process.
Unlike 𝒱 no 𝒱n contains any triangles. As n →∞, the vertices of the quadrangles of 𝒱n tend to circularity, so that the sums of their opposite interior angles tend to π.
We conducted a blind tasting sensory evaluation experiment and a chemical analysis of four craft hard apple ciders from the Pacific Northwest of the USA. Using the sensory and demographic data collected during the experiment, we estimated the consumer willingness-to-pay (WTP), using a contingent valuation model. Overall liking, taste, and aroma, from the sensory evaluation, as well as age of the sampler and if the sampler was a cider drinker, contributed positively to the WTP. In contrast, if the subject was a beer drinker this reduced their WTP. From the chemical analysis we found that tannin level had a positive effect on WTP, but an increased level of sweetness, as part of a ratio of specific gravity to acid, decreased consumer WTP. (JEL Classifications: C91, D12, L66, Q13)
Reliability and degradation processes in broad-area InGaAs-AlGaAs strained quantum well (QW) lasers are under intensive investigation because these lasers are the key components for fiber lasers and amplifiers that have found both industrial and military applications in recent years. Unlike single-mode lasers that were developed for high reliability telecom applications, broad-area lasers were mainly targeted for applications that require less stringent reliability of the lasers until recently. Especially, the lack of field reliability data is a concern for satellite communication systems where high reliability is required of lasers for long-term duration. For our present study, we addressed this concern by performing long-term life-tests of broad-area InGaAs-AlGaAs strained QW lasers and also by studying mechanisms that are responsible for catastrophic degradation of the lasers.
Little is known regarding the underlying relationship between smoking initiation and current quantity smoked during adolescence into young adulthood. It is possible that the influences of genetic and environmental factors on this relationship vary across sex and age. To investigate this further, the current study applied a common causal contingency model to data from a Virginia-based twin study to determine: (1) if the same genetic and environmental factors are contributing to smoking initiation and current quantity smoked; (2) whether the magnitude of genetic and environmental factor contributions are the same across adolescence and young adulthood; and (3) if qualitative and quantitative differences in the sources of variance between males and females exist. Study results found no qualitative or quantitative sex differences in the relationship between smoking initiation and current quantity smoked, though relative contributions of genetic and environmental factors changed across adolescence and young adulthood. More specifically, smoking initiation and current quantity smoked remain separate constructs until young adulthood, when liabilities are correlated. Smoking initiation is explained by genetic, shared, and unique environmental factors in early adolescence and by genetic and unique environmental factors in young adulthood; while current quantity smoked is explained by shared environmental and unique environmental factors until young adulthood, when genetic and unique environmental factors play a larger role.
The electronic structure of delta plutonium (δ-Pu) and plutonium compounds is investigated using photoelectron spectroscopy (PES). Results for δ-Pu show a small component of the valence electronic structure which might reasonably be associated with a 5f6 configuration. PES results for PuTe are used as an indication for the 5f6 configuration due to the presence of atomic multiplet structure. Temperature dependent PES data on δ-Pu indicate a narrow peak centered 20 meV below the Fermi energy and 100 meV wide. The first PES data for PuCoIn5 indicate a 5f electronic structure more localized than the 5fs in the closely related PuCoGa5. There is support from the PES data for a description of Pu materials with an electronic configuration of 5f5 with some admixture of 5f6 as well as a localized/delocalized 5f5 description.
We have examined spectrally resolved photoconductivity and photoluminescence from InAs/Ga1–xInxSb strained-layer superlattices, which have been proposed as infrared detectors in the 8-14 μm region. Our measurements indicate that the energy gaps of the strained–layer superlattices are substantially smaller than those of InAs/GaSb superlattices with similar layer thicknesses, in agreement with previous theoretical predictions. Measurements on InAs/Ga1–xInxSb superlattices with x=0 and 0.25 and layer thicknesses of 25 – 45 A indicate superlattice band gaps of 3 – 15 μm, in excellent agreement with gaps calculated by a two band k · p model. Our results demonstrate that far-infrared energy gaps are compatible with the thin layers necessary for strong optical absorption in type-IT superlattices, and suggest that InAs/Ga1–xInxSb superlattices are promising candidates for far-infrared detection.
Little has been published about Te-rich ZnSexTel−x grown at low temperatures, in spite of some successes in the fabrication of wide band gap light emitting devices from ZnSeTe alloys grown at higher temperatures. We present x-ray diffraction and photoluminescence (PL) spectra for ZnSeTe epilayers and ZnSeTe/ZnTe superlattices grown by molecular beam epitaxy (MBE). These we compare with measurements on ZnTe, ZnSe and CdZnTe epilayers and on CdZnTe/ZnTe superlattices grown under similar conditions and also with data published for ZnSeTe alloys grown at high temperatures. Equilibrium phase diagrams for the ZnSeTe alloy system suggest a large miscibility gap at MBE growth temperatures; this may account for some unusual features in the (PL) spectra and for large line widths in the x-ray data. In spite of these possible miscibility problems, we find that ZnSeTe alloys luminesce brightly.
The implications for recent reports of large valence band offsets the HgTe-CdTe heterojunction are examined. The variation of the band gap and effective mass for transport normal to the layers in the superlattice is examined in detail.
Rapid thermal chemical vapor deposition (RTCVD) oxides formed using TEOS and oxygen (O2) are compared with RTCVD oxides formed using silane (SiH4) and nitrous oxide (N2O). These oxides were deposited under varying pressure and gas composition to investigate the film step coverage and electrical properties. Cross-sectional scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used in determining the oxide step coverage. Excellent oxide conformality, greater than 90 %, was achieved with SiH4 and N2O over a wide range of aspect ratios. The average breakdown field obtained for the SiH4/N2O oxides is approximately 13 MV/cm, which is greater than values measured for oxides formed by conventional dry thermal process. Oxides deposited using TEOS typically have an average breakdown field of about 8 MV/cm. We conclude that the SiH4/N2O oxide process for the deposition of SiO2 films in a RTCVD reactor is a very promising candidate for sidewall spacer formation in advanced device applications.
Unimplanted n-type GaAs epitaxial layers have been annealed under the same conditions as those required to activate ion implants. If the duration of the anneal is sufficiently long (e.g. 10 min at 800°C) acceptor ions accumulate at the surface with a concentration of about 2×1022 m−3. Schottky contacts to annealed samples always show increased current densities up to six orders of magnitude greater than those in unannealed layers. This has the effect of lowering the Q values of varactor diodes made out of this material, up to frequencies of 1 GHz.
Rapid thermal chemical vapor deposition (RTCVD) has been investigated as an alternative to low pressure chemical vapor deposition (LPCVD) for formation of sidewall spacer dielectric. Silane (SiH 4 ) and tetraethylorthosilicate (TEOS) were chosen as the silicon gas sources in these studies. Reasonable deposition rates were obtained for RTCVD oxides, oxynitrides and nitrides for use in thin sidewall spacer application. Refractive index and etch rate measurements suggest that oxides deposited with a 2 % flow rate ratio of SiH 4 /N2O and annealed at 900 °C for 10 seconds produces films with excellent structural quality. Refractive index and wet etch rate both exhibit a linear dependence with the gas flow ratio. An increase in deposition pressure decreased the refractive index while increasing the etch rate. Oxide and oxynitride dielectrics formed using SiH 4 had a much superior step coverage over a wide range of aspect ratios than TEOS dielectrics. Dit and breakdown fields for oxides and oxynitrides with 3 atomic % nitrogen were comparable to that of thermal oxide indicating their good electrical quality. The results reported suggest that RTCVD sidewall spacers are a promising candidate for use in future MOSFET devices.
Recent progress on the use of molecular engineering approaches for the enhancement and spectral tuning of the optical limiting responses of phthalocyanine complexes is presented. Examples are given involving the use of the heavy-atom approach to enhance the limiting response of naphthalocyanines and of donor substitution of naphthalocyanines to red shift the optical limiting response, as demonstrated for indium and tin octabutoxynaphthalocyanines. These approaches have led to new materials for optical limiting with potential for high performance. An experimental demonstration of the “bottleneck” limiter concept, in which the optical-limiting material is distributed nonhomogeneously to permit strong pumping of excited-state population throughout the interaction region, is presented and shows an order-of-magnitude increase in pulse suppression compared to a homogeneous distribution, without an increase in linear absorbance.