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Many results are known about test ideals and $F$-singularities for ${\bf Q}$-Gorenstein rings. In this paper we generalize many of these results to the case when the symbolic Rees algebra $O_X \oplus O_X(-K_X) \oplus O_X(-2K_X) \oplus ...$ is finitely generated (or more generally, in the log setting for $-K_X - \Delta$). In particular, we show that the $F$-jumping numbers of $\tau(X, a^t)$ are discrete and rational. We show that test ideals $\tau(X)$ can be described by alterations as in Blickle-Schwede-Tucker (and hence show that splinters are strongly $F$-regular in this setting -- recovering a result of Singh). We demonstrate that multiplier ideals reduce to test ideals under reduction modulo $p$ when the symbolic Rees algebra is finitely generated. We prove that Hartshorne-Speiser-Lyubeznik-Gabber type stabilization still holds. We also show that test ideals satisfy global generation properties in this setting., Comment: Lemma 2.10 was incorrect, it stated something that was too strong. We have restated Lemma 2.10 correctly we believe. Fortunately, we only needed the new weaker statement. This also corrects the published version

Digestive efficiency (DE) is influenced by many factors including food type or quality. Assimilation efficiency (AE) and DE of 12 captive harp seals (Phoca groenlandica) were estimated for five prey types in large outdoor seawater tanks. In trials of > 9 days' duration, the seals were fed Atlantic cod (Gadus morhua), Arctic cod (Boreogadus saida), Greenland halibut (Reinhardtius hippoglossoides), Atlantic herring (Clupea harengus), and capelin (Mallotus villosus). Fish were marked with inert tracers so that faecal samples could be matched to individual animals. AE (digestibility of dry matter) was estimated from the relative concentration of Mn2+in food and faeces. DE (digestible energy) was estimated from the relative concentrations of both Mn2+and energy in food and faeces. AE and DE values were high, but varied among the fish species (DE: Atlantic cod 93.5%; Arctic cod 93.5%; halibut 94.7%; capelin 95.7%; herring 96.6%). Both estimates of digestive efficiency were positively correlated with prey energy density. For most prey, AE and DE were not correlated with meal size, number of prey in a meal, size of prey, or seal body mass. However, digestive efficiency was greater in seals fed smaller Atlantic cod, or meals of greater mass. Quantifying estimates of digestive efficiency is important for formulating energy-based population consumption models, and so should be improved. It is recommended that more pinniped species be studied in captivity, that experiments last longer, and that the number of individuals studied be increased so that individual differences can be investigated.

Asymptotic inference results for the coefficients of variation of normal populations are presented in this article. This includes formulas for test statistics, power, confidence intervals, and simultaneous inference. The results are based on the asymptotic normality of the sample coefficient of variation as derived by Miller (1991). An example which compares the homogeneity of bone test samples produced from two different methods is presented.

Background: In a prior study, a DNA prime / adenovirus boost vaccine (DNA/Ad) expressing P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1) (NMRC-M3V-D/Ad-PfCA Vaccine) induced 27% protection against controlled human malaria infection (CHMI). To investigate the contribution of DNA priming, we tested the efficacy of adenovirus vaccine alone (NMRC-M3V-Ad-PfCA ) in a Phase 1 clinical trial. Methodology/Principal Findings: The regimen was a single intramuscular injection with two non-replicating human serotype 5 adenovectors encoding CSP and AMA1, respectively. One x 1010 particle units of each construct were combined prior to administration. The regimen was safe and well-tolerated. Four weeks later, 18 study subjects received P. falciparum CHMI administered by mosquito bite. None were fully protected although one showed delayed onset of parasitemia. Antibody responses were low, with geometric mean CSP ELISA titer of 381 (range < 50–1626) and AMA1 ELISA of 4.95 µg/mL (range 0.2–38). Summed ex vivo IFN-γ ELISpot responses to overlapping peptides were robust, with geometric mean spot forming cells/million peripheral blood mononuclear cells [sfc/m] for CSP of 273 (range 38–2550) and for AMA1 of 1303 (range 435–4594). CD4+ and CD8+ T cell IFN-γ responses to CSP were positive by flow cytometry in 25% and 56% of the research subjects, respectively, and to AMA1 in 94% and 100%, respectively. Significance: In contrast to DNA/Ad, Ad alone did not protect against CHMI despite inducing broad, cell-mediated immunity, indicating that DNA priming is required for protection by the adenovirus-vectored vaccine. ClinicalTrials.gov Identifier: NCT00392015.

Objective. To examine racial–ethnic differences in asthma controller medication use among insured U.S. children. Data Sources. Linked nationally representative data from the Medical Expenditure Panel Survey (2005–2008), the 2000 Decennial Census, and the National Health Interview Survey (2004–2007). Study Design. The study quantifies the portion of racial–ethnic differences in children's controller use that are attributable to differences in need, enabling and predisposing characteristics. Principal Findings. Non-Hispanic black and Hispanic children were less likely to use controllers than non-Hispanic white children. Blinder-Oaxaca decomposition results indicated that observable characteristics explain less than 40 percent of the overall differential in controller use between non-Hispanic whites and non-Hispanic blacks. In contrast, observable characteristics explain more than two-thirds (71.3 percent) of the overall non-Hispanic white-Hispanic differential in controller use. For non-Hispanic blacks, a majority of the explained differential in controller use were attributed to enabling characteristics. For Hispanics, a significant portion of the explained differential in controller use was attributed to predisposing characteristics. In addition, a larger portion of the differential in controller use was explained by observable characteristics for publicly insured non-Hispanic black and Hispanic children. Conclusions. The large observed differences in controller use highlight the continuing challenges of ensuring that all U.S. children have access to quality asthma care.

Faeces were collected from four captive harbour seals (Phoca vitulina) that consumed known amounts of herring (Clupea harengus), walleye pollock (Theragra chalcogramma), Pacific hake (Merluccius productus), surf smelt (Hypomesus pretiosus), and juvenile chinook salmon (Oncorhynchus tshawytscha). The goal was to determine which structures (hard parts) passed through the digestive tract (e.g., eye lenses, scales, vertebrae, otoliths), and which of these could be used to determine the type and number of fish consumed. Nearly 5000 fish were consumed, from which over 50 000 hard parts were recovered from seal faeces. Scales were the most numerous of the 23 structures recovered (>20 000), followed by vertebrae, eye lenses, and otoliths. Morphological distinctiveness and digestive erosion of the structures varied among fish taxa. Two to five structures accounted for over 90% of the taxon-specific elements recovered, depending upon the species of fish consumed. Otoliths, which are used routinely to characterize pinniped diets, accounted for only 17% of the identified taxon-specific hard parts. The variation in types of structures and rates of recovery across taxa underscores the importance of using several types of hard parts to identify prey. Identifying several different prey structures increases the likelihood of identifying a prey type.

For many readers the term “microsimulation” may connote the use of data on persons (or establishments) to evaluate the possible consequences of a new or proposed policy. Such a definition, however, captures only some of the ways simulation is used within health services research. Consider studies that call for measures of after-tax income, eligibility for public insurance, or adherence to treatment regimes. In each case, micro data are enhanced using information from outside the dataset (tax rules, eligibility rules, or treatment guidelines), creating measures of value for researchers and policy makers. Simulated measures such as these can serve as building blocks for policy evaluations, but they may also play important roles in descriptive or behavioral analyses. In this article, we simulate the tax subsidy to private employer-sponsored insurance (ESI). ESI is the predominant form of health insurance in the nonelderly US population, covering 67.7 percent of adults and 58.3 percent of children for at least part of the year in 2009 (authors' calculations using the 2009 MEPS-HC). Current tax law provides strong subsidies to ESI by exempting employer premium contributions and most employee contributions from income and payroll taxes. The resulting “tax expenditure” is more than twice the tax expenditure for home mortgage interest and approximately half the size of Medicare or Medicaid.1 ESI tax subsidies are an ongoing source of policy debate. On the one hand, some have argued that ESI subsidies serve as the “glue” holding ESI risk pools together, mitigating predictable losses as low-risk workers cross-subsidize those with higher expected spending (Monheit, Nichols, and Selden 1996; Selden 1999; Selden and Bernard 2004). On the other hand, ESI subsidies tend to be poorly targeted, conferring the largest benefits on higher income families who are the least likely to be uninsured or covered by public insurance (Gruber 2002; Chernew, Cutler, and Keenan 2005). ESI subsidies may also encourage higher than optimal levels of coverage and medical care consumption (Feldstein 1973; Pauly 1986; Newhouse 1992). The Patient Protection and Affordable Care Act (PPACA) modifies ESI tax subsidies in several respects, increasing subsidies for small employers and reducing subsidies for high-premium plans (Kaiser Family Foundation 2011a). Nevertheless, concerns over equity and efficiency, in conjunction with concerns over federal debt, have motivated proposals for additional changes in this largest of individual tax preferences (Antos, Wilensky, and Kuttner 2008; Buchmueller et al. 2008; Furman 2008; Pauly 2008). Despite the policy importance of the ESI tax subsidy, the implicit nature of this “expenditure” means that it cannot be directly measured. Rather, it must be simulated. In principle, this appears to involve straightforward calculations based on marginal tax rates and premium contributions. However, worker marginal tax rates and employer/employee contributions are generally not found on a common dataset, so researchers must combine information from multiple sources (Gillette et al. 2010; Gruber 2011). Indeed, prior to 2012 even Internal Revenue Service (IRS) tax records have not contained the premium contribution data required to calculate ESI tax expenditures.2 Our approach uses data on workers from the Medical Expenditure Panel Survey Household Component (MEPS-HC) to create synthetic workforces for each establishment in the MEPS Insurance Component (IC), refining the method developed in Selden and Gray (2006). Another computational challenge is that tax subsidy calculations require assumptions regarding the incidence of employer contributions. Economists generally agree that workers bear the burden of employer ESI premium contributions through lower cash wages. There is far less agreement, however, on exactly how employers adjust cash wages when workers have heterogeneous health risks and make heterogeneous decisions regarding take-up and plan choice. Tax subsidy estimates typically rely on the “Statutory” assumption that each enrolled worker bears the cost of the employer's premium contribution to the plan in which he/she enrolled. The (implicit) assumption is that employers set cash wages after observing take-up and plan choice and that cash wage offsets do not reflect the health risks of workers (or their covered dependents). Relatively little is known, however, about the sensitivity of tax subsidy estimates to assumptions regarding the incidence of employer contributions. Selden and Bernard (2004) used simulation to explore the implications of alternative incidence assumptions for studies examining progressivity across households and worker incentives for risk pooling. We build on their approach, using simulation to explore the implications of assumptions regarding employer targeting of cash wage offsets for estimates of the aggregate ESI subsidy and its incidence across establishments. The next two sections describe the MEPS-IC and HC databases that we use and our simulation methods. The last two sections present our results and conclusions.

Let $k$ be an arbitrary field (of arbitrary characteristic) and let $X=[x_{i,j}]$ be a generic $m\times n$ matrix of variables. Denote by $I_{2}(X)$ the ideal in $k[X]=k[x_{i,j}:i=1,\ldots,m;j=1,\ldots,n]$ generated by the $2\times2$ minors of $X$. Using Grobner basis, we give a recursive formulation for the lengths of the $k[X]$-module $k[X]/(I_{2}(X)+(x_{1,1}^{q},\ldots,x_{m,n}^{q}))$ as $q$ varies over all positive integers. This is a generalized Hilbert–Kunz function, and our formulation proves that it is a polynomial function in $q$. We apply our method to give closed forms for these Hilbert–Kunz functions for cases $m\le2$.

The present paper describes the planning and preliminary design of passing lanes in difficult terrain in Southern California and is based on an investigation of approximately 560 km (350 mi) of two-lane highways in Imperial, San Diego, and Riverside counties. The need for passing opportunities has arisen for several reasons, the most important being the fact that long sections of highways are marked as no passing zones, which leads to extensive delays, driver frustration, an increased accidents. The planning techniques described herein include the use of video-logs to create a computer file documenting existing highway conditions and a two-lane highway simulation model. The TRARR (traffic on rural roads) simulation model was used to determine the impact of proposed passing lanes and turnouts on level of service. The use of the simulation model allowed the evaluation of a range of passing lane alternatives (including length and location) for a wide range of traffic, vehicle, and driver characteristics. In total, 117 new passing lanes and four turnouts were recommended for the 560 km (350 mi) of State routes that were evaluated.

The $F$-pure threshold is a numerical invariant of prime characteristic singularities, that constitutes an analogue of the log canonical thresholds in characteristic zero. We compute the $F$-pure thresholds of determinantal ideals, i.e., of ideals generated by the minors of a generic matrix.

The classical Witt vectors are a ubiquitous object in algebra and number theory. They arise as a functorial construction that takes perfect fields k of prime characteristic p > 0 to p-adically complete discrete valuation rings of characteristic 0 with residue field k and are universal in that sense. A. Dress and C. Siebeneicher generalized this construction by producing a functor W_G attached to any profinite group G. The classical Witt vectors are those attached to the p-adic integers. Here we examine the ring structure of W_G(k) for several examples of pro-p groups G and fields k of characteristic p. We will show that the structure is surprisingly more complicated than the classical case., 25 pages, 4 figures

If $X$ is Frobenius split, then so is its normalization and we explore conditions which imply the converse. To do this, we recall that given an $\mathcal{O}_X$-linear map $\phi : F_* \mathcal{O}_X \to \mathcal{O}_X$, it always extends to a map $\bar{\phi}$ on the normalization of $X$. In this paper, we study when the surjectivity of $\bar{\phi}$ implies the surjectivity of $\phi$. While this doesn't occur generally, we show it always happens if certain tameness conditions are satisfied for the normalization map. Our result has geometric consequences including a connection between $F$-pure singularities and semi-log canonical singularities, and a more familiar version of the ($F$-)inversion of adjunction formula., Comment: Minor changes, 21 pages, to appear in the Journal of Algebra

Acid–base transport in the renal collecting tubule is mediated by two canonical cell types: the β-intercalated cell secretes HCO 3 by an apical Cl:HCO 3 named pendrin and a basolateral vacuolar (V)-ATPase. Acid secretion is mediated by the α-intercalated cell, which has an apical V-ATPase and a basolateral Cl:HCO 3 exchanger (kAE1). We previously suggested that the β-cell converts to the α-cell in response to acid feeding, a process that depended on the secretion and deposition of an extracellular matrix protein termed hensin (DMBT1). Here, we show that deletion of hensin from intercalated cells results in the absence of typical α-intercalated cells and the consequent development of complete distal renal tubular acidosis (dRTA). Essentially all of the intercalated cells in the cortex of the mutant mice are canonical β-type cells, with apical pendrin and basolateral or diffuse/bipolar V-ATPase. In the medulla, however, a previously undescribed cell type has been uncovered, which resembles the cortical β-intercalated cell in ultrastructure, but does not express pendrin. Polymerization and deposition of hensin (in response to acidosis) requires the activation of β1 integrin, and deletion of this gene from the intercalated cell caused a phenotype that was identical to the deletion of hensin itself, supporting its critical role in hensin function. Because previous studies suggested that the conversion of β- to α-intercalated cells is a manifestation of terminal differentiation, the present results demonstrate that this differentiation proceeds from HCO 3 secreting to acid secreting phenotypes, a process that requires deposition of hensin in the ECM.

"History does not repeat itself," the British statesman A.J. Balfour once observed. "Historians repeat each other." Whatever its general validity, Balfour's remark seems applicable to many of the historical writings about the Vietnam War. For decades, Anglophone scholarship on the war has been polarized between the "orthodox" and "revisionist" schools. Those in the former group maintain that the war was unwinnable and America's defeat inevitable. The denizens of the latter camp insist just as stridently that a U.S. victory was attainable—and indeed was very nearly achieved, before it was abandoned due to incompetence, perfidy, or some combination of the two.

To compare users and nonusers of Veterans Affairs (VA) pharmacy services by age group.Cross-sectional.We used data on sociodemographics, health status, and medical conditions from the Medical Expenditure Panel Survey (MEPS) to compare users and nonusers of VA pharmacies for medications. Data were pooled for 2003-2005 to ensure adequate sample sizes. Student t tests were used to compare the means for each variable, and all analyses were adjusted for the complex sample design of the MEPS.Among both nonelderly (18-64 years) and elderly (or=65 years) veterans, a higher proportion who used VA pharmacy services versus those who did not use VA pharmacy services (1) were black (nonelderly: 17.7 % vs 7.4%, P.001; elderly: 9.4% vs 4.7%, P.001); (2) had no alternative insurance (nonelderly: 27.2% vs 4.8%, P.001; elderly: 36.3% vs 19.9%, P.001); (3) had lower incomes (nonelderly: 32.4% vs 11.5%, P.001; elderly: 32.4% vs 25.4%, P = .01); (4) had less than a high school education (nonelderly: 13.0% vs 6.5%, P.001; elderly: 27.5% vs 17.6%, P.001); (5) were disabled; and (6) reported poorer health. A higher percentage of nonelderly users reported a mental health condition (31.6% vs 19.4%, P.001).Veterans who use VA pharmacy services appear to be more ill than those who do not use VA pharmacy services. In addition, the VA appears to be a safety net for uninsured veterans who have mental health problems.

This affectionate but far from sentimental history was published in 1961 to mark the 450th anniversary of the foundation of St John's College, Cambridge. Edward Miller (1915–2000) was a medieval historian who spent most of his career teaching in Cambridge. An undergraduate and research fellow at St John's, he later went on to become Master of Fitzwilliam. His Portrait blends the history of St John's with wider developments in education, as well as social, political and economic history. As such it is a fine example of an institutional history written from within, with an unbiased assessment of the many changes the College had seen. The chapter on the period from 1918 to the early sixties, based on Miller's own reminiscences and those of his colleagues, is an important record of life in the college in an age of modernisation and change.