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We describe the survey design, calibration, commissioning, and emission-line detection algorithms for the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX). The goal of HETDEX is to measure the redshifts of over a million Lyα emitting galaxies between 1.88 < z < 3.52, in a 540 deg2 area encompassing a comoving volume of 10.9 Gpc3. No preselection of targets is involved; instead the HETDEX measurements are accomplished via a spectroscopic survey using a suite of wide-field integral field units distributed over the focal plane of the telescope. This survey measures the Hubble expansion parameter and angular diameter distance, with a final expected accuracy of better than 1%. We detail the project’s observational strategy, reduction pipeline, source detection, and catalog generation, and present initial results for science verification in the Cosmological Evolution Survey, Extended Groth Strip, and Great Observatories Origins Deep Survey North fields. We demonstrate that our data reach the required specifications in throughput, astrometric accuracy, flux limit, and object detection, with the end products being a catalog of emission-line sources, their object classifications, and flux-calibrated spectra.

Purpose: Successful voice therapy requires the patient to learn new vocal behaviors, but little is currently known regarding how vocal motor skills are improved and retained. To quantitatively characterize the motor learning process in a clinically meaningful context, a virtual task was developed based on the Vocal Function Exercises. In the virtual task, subjects control a computational model of a ball floating on a column of airflow via modifications to mean airflow (L/s) and intensity (dB-C) to keep the ball within a target range representing a normative ratio (dB × s/L). Method: One vocally healthy female and one female with nonphonotraumatic vocal hyperfunction practiced the task for 11 days and completed retention testing 1 and 6 months later. The mapping between the two execution variables (airflow and intensity) and one error measure (proximity to the normative ratio) was evaluated by quantifying distributional variability (tolerance cost and noise cost) and temporal variability (scaling index of detrended fluctuation analysis). Results: Both subjects reduced their error over practice and retained their performance 6 months later. Tolerance cost and noise cost were positively correlated with decreases in error during early practice and late practice, respectively. After extended practice, temporal variability was modulated to align with the task's solution manifold. Conclusions: These case studies illustrated, in a healthy control and a patient with nonphonotraumatic vocal hyperfunction, that the virtual floating ball task produces quantitative measures characterizing the learning process. Future work will further investigate the task's potential to enhance clinical assessment and treatments involving voice control.

What are the public opinion consequences when public policy moves in a more liberal or conservative direction? The accepted wisdom on ideology in public opinion is that it is largely ephemeral for most people. While this is undoubtedly true, it is also possible that the relative salience of ideology could vary over time. As ideological distinctions become more important in political debate, ideology itself may come to mean more to the mass public. In addition, while ideology may be a nebulous concept for individuals to grasp, perhaps on average it is sensitive to shifts in public policy.This paper represents an initial investigation of these questions, with an emphasis on the first question. It finds—tentatively—that as Congress and the President produce more major legislation that is polarized along ideological lines, people increasingly have ideologies, and those who have ideologies are increasingly polarized towards the ends of the scale.Prepared for delivery at the Colloquium on American Politics, October 31, 2005

What are the public opinion consequences when public policy moves in a more liberal or conservative direction? The accepted wisdom on ideology in public opinion is that it is largely ephemeral for most people. While this is undoubtedly true, it is also possible that the relative salience of ideology could vary over time. As ideological distinctions become more important in political debate, ideology itself may come to mean more to the mass public. In addition, while ideology may be a nebulous concept for individuals to grasp, perhaps on average it is sensitive to shifts in public policy. This paper represents an initial investigation of the these questions, with an emphasis on the first question. It finds—tentatively—that as Congress and the President produce more major legislation that is polarized along ideological lines, people increasingly have ideologies, and those who have ideologies are increasingly polarized towards the ends of the scale.

There are numerous models predicting the partisan distribution of seats in the U.S. House of Representatives using national-level variables. The partisan distribution in Congress is simply an aggregation of 435 separate elections. This paper is an attempt to formulate measures of differential partisan vulnerability in elections from individual election results. The measures constructed are compared to models in the literature. Findings indicate that either the measures are not indicative of the exposure thesis or that, similar to the literature on sociotropic versus “pocketbook” economic voting, the district-level causal mechanism is complex and unclear.

Recent successful tests of the Theater High-Altitude Air Defense System (THAAD) and the Exoatmospheric Kill Vehicle (EKV) against simulated incoming ballistic missiles have again thrust the issue of ballistic missile defense (BMD) into the policy spotlight. Scholars have typically included defense spending in studies of distributive politics. This paper studies the determinants of ballistic missile policy in Congress, distinguishing between the public sphere of floor voting and less-visible activism as measures of policy support. Many theories exist that purport to explain support for defense projects, yet few of them distinguish between different kinds of support. This paper advances the theory that funding support in Congress cannot be easily measured, and that voting is expected to show signs of rigid partisanship while cosponsorship–a better measure of true policy activism–reflects more nuanced influences. This theory is then tested against the data on Congress in the 1990s.

A prominent source of mutation in cancer is single-stranded DNA cytosine deamination by cellular APOBEC3 enzymes, which results in signature C-to-T and C-to-G mutations in TCA and TCT motifs. Although multiple enzymes have been implicated, reports conflict and it is unclear which protein(s) are responsible. Here we report the development of a selectable system to quantify genome mutation and demonstrate its utility by comparing the mutagenic activities of three leading candidates—APOBEC3A, APOBEC3B, and APOBEC3H. The human cell line, HAP1, is engineered to express the thymidine kinase (TK) gene of HSV-1, which confers sensitivity to ganciclovir. Expression of APOBEC3A and APOBEC3B, but not catalytic mutant controls or APOBEC3H, triggers increased frequencies of TK mutation and similar TC-biased cytosine mutation profiles in the selectable TK reporter gene. Whole genome sequences from independent clones enabled an analysis of thousands of single base substitution mutations and extraction of local sequence preferences with APOBEC3A preferring YTCW motifs 70% of the time and APOBEC3B 50% of the time (Y = C/T; W = A/T). Signature comparisons with breast tumor whole genome sequences indicate that most malignancies manifest intermediate percentages of APOBEC3 signature mutations in YTCW motifs, mostly between 50 and 70%, suggesting that both enzymes contribute in a combinatorial manner to the overall mutation landscape. Although the vast majority of APOBEC3A- and APOBEC3B-induced single base substitution mutations occur outside of predicted chromosomal DNA hairpin structures, whole genome sequence analyses and supporting biochemical studies also indicate that both enzymes are capable of deaminating the single-stranded loop regions of DNA hairpins at elevated rates. These studies combine to help resolve a long-standing etiologic debate on the source of APOBEC3 signature mutations in cancer and indicate that future diagnostic and therapeutic efforts should focus on both APOBEC3A and APOBEC3B. Author summary: A large source of mutation in cancer is attributable to single-stranded DNA cytosine to uracil (C-to-U) deamination by APOBEC3 family enzymes. Chromosomal DNA U's directly template the insertion of adenine (A), which results in C/G-to-T/A mutations. Chromosomal U's also trigger error-prone DNA repair processes, which less directly result in C/G-to-T/A mutations, C/G-to-G/C mutations, and more complex events such as insertion/deletion mutations. We report a human cell line for cancer mutation studies, where mutations can be identified selectively or by genomic DNA sequencing. Only APOBEC3A and APOBEC3B proved capable of inflicting the aforementioned types of single base substitution mutations. Interestingly, 70% and 50% of the single base substitution mutations attributable to APOBEC3A and APOBEC3B, respectively, occurred in TCA and TCT trinucleotide motifs preceded by a pyrimidine (T or C). This is significant because most APOBEC3-positive breast tumors exhibit an intermediate percentage of signature mutations in these broader tetranucleotide motifs, which supports the idea that both APOBEC3A and APOBEC3B contribute in a combinatorial manner to the overall mutation landscape in these tumors. [ABSTRACT FROM AUTHOR]

Aims: Primary head/neck mucosal melanomas (MMs) are rare and exhibit aggressive biologic behaviour and elevated mutational loads. The molecular mechanisms responsible for high genomic instability observed in head/neck MMs remain elusive. The DNA cytosine deaminase APOBEC3B (A3B) constitutes a major endogenous source of mutation in human cancer. A3B‐related mutations are identified through C‐to‐T/−G base substitutions in 5′‐TCA/T motifs. Herein, we present immunohistochemical and genomic data supportive of a role for A3B in head/neck MMs. Methods and results: A3B protein levels were assessed in oral (n = 13) and sinonasal (n = 13) melanomas, and oral melanocytic nevi (n = 13) by immunohistochemistry using a custom rabbit α‐A3B mAb (5210‐87‐13). Heterogeneous, selective‐to‐diffuse, nuclear only, A3B immunopositivity was observed in 12 of 13 (92.3%) oral melanomas (H‐score range = 9–72, median = 40) and 8 of 13 (62%) sinonasal melanomas (H‐score range = 1–110, median = 24). Two cases negative for A3B showed prominent cytoplasmic staining consistent with A3G. A3B protein levels were significantly higher in oral and sinonasal MMs than intraoral melanocytic nevi (P < 0.0001 and P = 0.0022, respectively), which were A3B‐negative (H‐score range = 1–8, median = 4). A3B levels, however, did not differ significantly between oral and sinonasal tumours (P > 0.99). NGS performed in 10 sinonasal MMs revealed missense NRAS mutations in 50% of the studied cases and one each KIT and HRAS mutations. Publicly available whole‐genome sequencing (WGS) data disclosed that the number of C‐to‐T mutations and APOBEC3 enrichment score were markedly elevated in head/neck MMs (n = 2). Conclusion: The above data strongly indicate a possible role for the mutagenic enzyme A3B in head/neck melanomagenesis, but not benign melanocytic neoplasms. [ABSTRACT FROM AUTHOR]

No known research has examined the concentration and flux of dissolved organic carbon (DOC) for stemflow across temporal scales from within single storm events to seasonal and annual scales or employed UV-Vis spectral metrics to examine the chemical character of dissolved organic matter (DOM) of stemflow drainage. Thus, our study examined stemflow DOC concentration and flux and DOM character from American beech (Fagus grandifolia Ehrh.) and yellow poplar (Liriodendron tulipifera L.) to address this data gap. Intrastorm stemflow DOC concentrations and fluxes diminished by an order of magnitude over time for American beech but remained relatively constant for yellow poplar. Stemflow DOM aromaticity, however, generally increased and [E.sub.2]: [E.sub.3] ratios generally decreased as events progressed, suggesting transport of different compounds at different moments. Although less enriched in DOC than yellow poplar, American beech stemflow DOC fluxes were double per annum. Differential interspecific stemflow DOM characteristics are ascribed to (i) significant differences in [SUVA.sub.254] values (aromaticity) for the leafless season and annually and (ii) significantly higher [E.sub.2]: [E.sub.3] and [S.sub.R] ratios for yellow poplar stemflow than for American beech annually and across leafed and leafless seasons. Our results suggest that stemflow significantly affects the amount and chemical character of carbon flux to the forest floor that may engender hot spots around tree boles. Resume: Aucune recherche connue n'a porte sur la concentration et le flux de carbone organique dissout (COD) associe au ruissellement sur le tronc a differentes echelles temporelles: soit pendant des tempetes particulieres ou a des echelles saisonniere et annuelle, ni utilise des mesures spectrales dans l'ultraviolet et le visible pour etudier les caracteristiques chimiques de la matiere organique dissoute (MOD) associee au ruissellement sur le tronc. Par consequent, notre etude a porte sur le flux et la concentration de COD associe au ruissellement sur le tronc ainsi que sur les caracteristiques de la MOD chez le hetre a grandes feuilles (Fagus grandifolia Ehrh.) et le tulipier de Virginie (Liriodendron tulipifera L.) afin de combler cette lacune. Pendant les tempetes, le flux et la concentration de COD associe au ruissellement sur le tronc ont diminue avec le temps d'un ordre de grandeur chez le hetre a grandes feuilles mais sont demeures relativement constants chez le tulipier de Virginie. Cependant, l'aromaticite de la MOD associee au ruissellement sur le tronc a generalement augmente et le rapport [E.sub.2]: [E.sub.3] a generalement diminue a mesure que les evenements progressaient, ce qui indique que differents composes seraient transportes a differents moments. Bien que moins riche en COD, le flux de COD associe au ruissellement sur le tronc du hetre a grandes feuilles etait sur une base annuelle deux fois plus eleve que celui du tulipier de Virginie. Les differences interspecifiques dans les caracteristiques de la MOD associee au ruissellement sur le tronc sont dues a (i) d'importantes differences dans les valeurs de [SUVA.sub.254] (aromaticite) pendant la saison sans feuilles et annuellement et (ii) des poids moleculaires relatifs du COD (rapports [E.sub.2]: [E.sub.3] et [S.sub.R]) associe au ruissellement sur le tronc significativement plus eleves chez le tulipier de Virginie que chez le hetre a grandes feuilles annuellement et pendant les saisons avec et sans feuilles. Nos resultats indiquent que le ruissellement sur le tronc a un effet significatif sur la quantite et les caracteristiques chimiques du flux de carbone vers la couverture morte et qu'il peut engendrer des points chauds autour du tronc des arbres. [Traduit par la Redaction], Introduction Canopy-derived hydrologic fluxes travel to the forest floor along two flow paths: throughfall and stemflow (Levia and Frost 2003; Levia and Frost 2006). Throughfall is the partition of incident [...]

The veto is one of the few formal powers accorded to the president of the United States, yet it plays a central role in many theories of the executive branch and in theories of congressional action as well To be more precise, the threat of a future veto is generally held to be the important component. However, there have been few empirical or theoretical studies of veto threats. This article presents new systematic data on the veto 'threats' of President Dwight Eisenhower. These data are analyzed to test novel theories regarding the relation of future veto threats to the outcomes of past veto threats. Specifically, this theory extends concepts of credibility of threat to include information that is specific to both the president in question and that president's then-current history of congressional interactions. Support is found for the theory that a president who 'cries wolf' and fails to carry out threats will find Congress less responsive to future threats, unless and until the president's credibility is reestablished. DOI: 10.1080/07343469.2010.495249