Fano Schemes of Complete Intersections in Toric Varieties

We study Fano schemes $F_k(X)$ for complete intersections $X$ in a projective toric variety $Y\subset \mathbb{P}^n$. Our strategy is to decompose $F_k(X)$ into closed subschemes based on the irreducible decomposition of $F_k(Y)$ as studied by Ilten and Zotine. We define the expected dimension for these subschemes, which always gives a lower bound on the actual dimension. Under additional assumptions, we show that these subschemes are non-empty and smooth of the expected dimension. Using tools from intersection theory, we can apply these results to count the number of linear subspaces in $X$ when the expected dimension of $F_k(X)$ is zero.Comment: 26 pages, 3 figure

Hypergeometric decomposition of symmetric K3 quartic pencils

We study the hypergeometric functions associated to five one-parameter deformations of Delsarte K3 quartic hypersurfaces in projective space. We compute all of their Picard--Fuchs differential equations; we count points using Gauss sums and rewrite this in terms of finite field hypergeometric sums; then we match up each differential equation to a factor of the zeta function, and we write this in terms of global L-functions. This computation gives a complete, explicit description of the motives for these pencils in terms of hypergeometric motives.Comment: 70 pages, minor revision, to appear in Research in the Mathematical Science

A maximally-graded invertible cubic threefold that does not admit a full exceptional collection of line bundles

We show that there exists a cubic threefold defined by an invertible polynomial that, when quotiented by the maximal diagonal symmetry group, has a derived category which does not have a full exceptional collection consisting of line bundles. This provides a counterexample to a conjecture of Lekili and Ueda.Comment: 8 pages, minor revision, to appear in Forum of Math, Sigm

Exceptional Collections for Mirrors of Invertible Polynomials

We prove the existence of a full exceptional collection for the derived category of equivariant matrix factorizations of an invertible polynomial with its maximal symmetry group. This proves a conjecture of Hirano--Ouchi. In the Gorenstein case, we also prove a stronger version of this conjecture due to Takahashi. Namely, that the full exceptional collection is strong.Comment: 14 pages, Counterexample retracted thanks to K. Ueda. References adde

A survey of current reproducibility practices in linguistics publications

Poster: In order to move forward toward reproducible research in linguistics, we first need to know where we are now with regard to our practices for methodological clarity and data citation in publications. In this poster we share the results of a study of over 370 journal articles, dissertations, and grammars, which is taken as a sample of current practices in the field. The publications all come from a ten-year span. The journals were selected for broad coverage. Grammars included published grammars and dissertations written as grammars, with broad geographic coverage, both in terms of subject language and publisher or university.These publications are critiqued on the basis of transparency of data source, data collection methods, analysis, and storage. While we find examples of transparent reporting, most of the surveyed research does not include key metadata, methodological information, or citations that are resolvable to the data on which the analyses are based.In order to move forward toward reproducible research in linguistics, we first need to know where we are now with regard to our practices for methodological clarity and data citation in publications. In this poster we share the results of a study of over 370 journal articles, dissertations, and grammars, which is taken as a sample of current practices in the field. The publications all come from a ten-year span. The journals were selected for broad coverage. Grammars included published grammars and dissertations written as grammars, with broad geographic coverage, both in terms of subject language and publisher or university.These publications are critiqued on the basis of transparency of data source, data collection methods, analysis, and storage. While we find examples of transparent reporting, most of the surveyed research does not include key metadata, methodological information, or citations that are resolvable to the data on which the analyses are based.This material is based upon work supported by the National Science Foundation under grant SMA-1447886

Professional decision-making in medicine: Development of a new measure and preliminary evidence of validity

INTRODUCTION: This study developed a new Professional Decision-Making in Medicine Measure that assesses the use of effective decision-making strategies: seek help, manage emotions, recognize consequences and rules, and test assumptions and motives. The aim was to develop a content valid measure and obtain initial evidence for construct validity so that the measure could be used in future research or educational assessment. METHODS: Clinical scenario-based items were developed based on a review of the literature and interviews with physicians. For each item, respondents are tasked with selecting two responses (out of six plausible options) that they would choose in that situation. Three of the six options reflect a decision-making strategy; these responses are scored as correct. Data were collected from a sample of 318 fourth-year medical students in the United States. They completed a 16-item version of the measure (Form A) and measures of social desirability, moral disengagement, and professionalism attitudes. Professionalism ratings from clerkships were also obtained. A sub-group (n = 63) completed a second 16-item measure (Form B) to pilot test the instrument, as two test forms are useful for pre-posttest designs. RESULTS: Scores on the new measure indicated that, on average, participants answered 75% of items correctly. Evidence for construct validity included the lack of correlation between scores on the measure and socially desirable responding, negative correlation with moral disengagement, and modest to low correlations with professionalism attitudes. A positive correlation was observed with a clerkship rating focused on professionalism in peer interactions. CONCLUSIONS: These findings demonstrate modest proficiency in the use of decision-making strategies among fourth-year medical students. Additional research using the Professional Decision-Making Measure should explore scores among physicians in various career stages, and the causes and correlates of scores. Educators could utilize the measure to assess courses that teach decision-making strategies

Putting practice into words: The state of data and methods transparency in grammatical descriptions

Language documentation and description are closely related practices, often performed as part of the same fieldwork project on an un(der)-studied language. Research trends in recent decades have seen a great volume of publishing in regards to the methods of language documentation, however, it is not clear that linguists' awareness of the importance of robust data-collection methods is translating into transparency about those methods or data citation in resultant publications. We analyze 50 dissertations and 50 grammars from a ten-year span (2003-2012) to assess the current state of the field. Publications are critiqued on the basis of transparency of data collection methods, analysis and storage, as well as citation of primary data. While we found examples of transparent reporting in these areas, much of the surveyed research does not include key information about methodology or data. We acknowledge that descriptive linguists often practice good methodology in data collection, but as a field we need to build a better culture with regard to making this clear in research writing. Thus we conclude with suggested benchmarks for the kind of information we believe is vital for creating a rich and useful research methodology in both long and short format descriptive research writing.National Foreign Language Resource Cente

Temperature and CO\u3csub\u3e2\u3c/sub\u3e additively regulate physiology, morphology and genomic responses of larval sea urchins, strongylocentrotus purpuratus

Ocean warming and ocean acidification, both consequences of anthropogenic production of CO2, will combine to influence the physiological performance of many species in the marine environment. In this study, we used an integrative approach to forecast the impact of future ocean conditions on larval purple sea urchins (Strongylocentrotus purpuratus) from the northeast Pacific Ocean.In laboratory experiments that simulated ocean warming and ocean acidification, we examined larval development, skeletal growth, metabolism and patterns of gene expression using an orthogonal comparison of two temperature (138C and 188C) and pCO2 (400 and 1100 matm) conditions. Simultaneous exposure to increased temperature and pCO2 significantly reduced larval metabolism and triggered a widespread downregulation of histone encoding genes. pCO2 but not temperature impaired skeletal growth and reduced the expression of a major spicule matrix protein, suggesting that skeletal growth will not be further inhibited by ocean warming. Importantly, shifts in skeletal growth were not associated with developmental delay. Collectively, our results indicate that global change variables will have additive effects that exceed thresholds for optimized physiological performance in this keystone marine species. © 2013 The Author(s) Published by the Royal Society. All rights reserved