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Seagrasses are highly productive, but human nearshore activities have reduced their global distribution by >29% since the twentieth century. In the United States and Canada, the native seagrass Zostera marina (eelgrass) provides habitat for many species and multiple ecosystem services. By supplying spawning surface for fish and substrate for invertebrates, eelgrass creates foraging areas for high densities of migratory birds. Eelgrass beds stabilize sediment, protect adjacent shorelines, improve water quality, and sequester carbon in their underlying substrate. San Francisco Bay (California, USA) is a significant estuary for eelgrass, and recent surveys show that eelgrass beds are in decline. Protecting eelgrass is a conservation priority for federal, state, and local agencies, yet few studies have documented the extent of eelgrass loss due to human impacts such as boat anchoring. The purpose of our study was to provide factual evidence for policy makers by quantifying damage to eelgrass caused by illegal anchor-outs in San Francisco Bay, an issue that has been disputed for decades. Using aerial imagery and GIS analyses, we determined the amount of direct damage to eelgrass caused by anchor-outs. We found that boats damage up to 41% of the eelgrass bed, and each boat may cause up to 0.3 ha of damage. These results can be used to inform decisions about anchor-outs by stakeholders and government agencies. Furthermore, our efficient analytical approach could be implemented in other coastal regions.

We prove a Chevalley formula for anti-dominant weights in the torus-equivariant K-group of semi-infinite flag manifolds, which is described explicitly in terms of semi-infinite Lakshmibai-Seshadri paths (or equivalently, quantum Lakshmibai-Seshadri paths); in contrast to the Chevalley formula for dominant weights in our previous paper [17] , the formula for anti-dominant weights has a significant finiteness property. Based on geometric results established in [17] , our proof is representation-theoretic, and the Chevalley formula for anti-dominant weights follows from a certain identity for the graded characters of Demazure submodules of a level-zero extremal weight module over a quantum affine algebra; in the proof of this identity, we make use of the (combinatorial) standard monomial theory for semi-infinite Lakshmibai-Seshadri paths, and also a string property of Demazure-like subsets of the set of semi-infinite Lakshmibai-Seshadri paths of a fixed shape, which gives an explicit realization of the crystal basis of a level-zero extremal weight module.

Toxin-producing cyanobacteria are increasing in rivers and streams globally, leading to growing concerns over their potential impacts on aquatic ecosystems. The present study was designed to culture field-collected Phormidium in the laboratory, identify individual species, conduct chemical analyses to identify cyanotoxins, and conduct toxicity tests to investigate the potential for this genera to impact stream health. Freshwater toxicity tests were conducted with standard US Environmental Protection Agency invertebrate test protocols with culture water used to grow 3 Phormidium strains isolated from the Russian River (CA, USA). Enzyme linked immunosorbent assays were used to measure total anatoxin concentrations. Culture waters from the 3 Phormidium strains were highly toxic to Ceriodaphnia dubia, Hyalella azteca, and Chironomus dilutus. The C. dubia 7-d survival median lethal concentrations were 0.71, 0.49, and 0.56 μg/L anatoxin for Phormidum strains 1, 2, and 3, respectively. The 7-d reproduction inhibitory concentrations, 25% were 0.55, 0.32, and 0.30 μg/L anatoxin for strains 1, 2, and 3, respectively. Chironomus dilutus survival was reduced at concentrations

We introduce generalized global Weyl modules and relate their graded characters to nonsymmetric Macdonald polynomials and nonsymmetric q-Whittaker functions. In particular, we show that the series part of the nonsymmetric q-Whittaker function is a generating function for the graded characters of generalized global Weyl modules.

The purpose of this article is to work out the details of the Ram–Yip formula for nonsymmetric Macdonald–Koornwinder polynomials for the double affine Hecke algebras of not-necessarily reduced affine root systems. It is shown that the $$t\rightarrow 0$$ equal-parameter specialization of nonsymmetric Macdonald polynomials admits an explicit combinatorial formula in terms of quantum alcove paths, generalizing the formula of Lenart in the untwisted case. In particular, our formula yields a definition of quantum Bruhat graph for all affine root systems. For mixed type, the proof requires the Ram–Yip formula for the nonsymmetric Koornwinder polynomials. A quantum alcove path formula is also given at $$t\rightarrow \infty $$ . As a consequence, we establish the positivity of the coefficients of nonsymmetric Macdonald polynomials under this limit, as conjectured by Cherednik and the first author. Finally, an explicit formula is given at $$q\rightarrow \infty $$ , which yields the p-adic Iwahori–Whittaker functions of Brubaker, Bump, and Licata.

Toxin-producing cyanobacteria are increasing in rivers and streams globally, leading to growing concerns over their potential impacts on aquatic ecosystems. The present study was designed to culture field-collected Phormidium in the laboratory, identify individual species, conduct chemical analyses to identify cyanotoxins, and conduct toxicity tests to investigate the potential for this genera to impact stream health. Freshwater toxicity tests were conducted with standard US Environmental Protection Agency invertebrate test protocols with culture water used to grow 3 Phormidium strains isolated from the Russian River (CA, USA). Enzyme linked immunosorbent assays were used to measure total anatoxin concentrations. Culture waters from the 3 Phormidium strains were highly toxic to Ceriodaphnia dubia, Hyalella azteca, and Chironomus dilutus. The C. dubia 7-d survival median lethal concentrations were 0.71, 0.49, and 0.56 μg/L anatoxin for Phormidum strains 1, 2, and 3, respectively. The 7-d reproduction inhibitory concentrations, 25% were 0.55, 0.32, and 0.30 μg/L anatoxin for strains 1, 2, and 3, respectively. Chironomus dilutus survival was reduced at concentrations2 μg/L anatoxin by all 3 strains, and the H. azteca 96-h lethal concentrations, 25% were 2.82, 1.26, and 5.30 μg/L for strains 1, 2, and 3, respectively. Additional liquid chromatography-mass spectrometry analyses demonstrated that the likely anatoxin variant in these cultures was dihydro-anatoxin-a. The results suggest that anatoxins produced by Phormidium have the potential to impact stream macroinvertebrates. Environ Toxicol Chem 2018;37:2851-2859. © 2018 SETAC.

We study walk algebras and Hecke algebras for Kac-Moody root systems. Each choice of orientation for the set of real roots gives rise to a corresponding "oriented" basis for each of these algebras. We show that the notion of distinguished subexpression naturally arises when studying the transition matrix between oriented bases. We then relate these notions to the geometry of Kac-Moody flag varieties and Bott-Samelson varieties. In particular, we show that the number of points over a finite field in certain intersections of these varieties is given by change of basis coefficients between oriented bases of the Hecke algebra. Using these results we give streamlined derivations of Deodhar's formula for $R$-polynomials and point-counting formulas for specializations of nonsymmetric Macdonald polynomials $E_\lambda(\mathsf{q},t)$ at $\mathsf{q}=0,\infty$.

This work is devoted to the theory of nil-DAHA for the root system A1 and its applications to symmetric and nonsymmetric (spinor) global q-Whittaker functions, integrating the q-Toda eigenvalue problem and its Dunkl-type nonsymmetric version.

We present two new connections between the inhomogeneous stochastic higher spin six vertex model in a quadrant and integrable stochastic systems from the Macdonald processes hierarchy. First, we show how Macdonald $q$-difference operators with $t=0$ (an algebraic tool crucial for studying the corresponding Macdonald processes) can be utilized to get $q$-moments of the height function $\mathfrak{h}$ in the higher spin six vertex model first computed in arXiv:1601.05770 using Bethe ansatz. This result in particular implies that for the vertex model with the step Bernoulli boundary condition, the value of $\mathfrak{h}$ at an arbitrary point $(N+1,T)\in\mathbb{Z}_{\ge2}\times\mathbb{Z}_{\ge1}$ has the same distribution as the last component $\lambda_N$ of a random partition under a specific $t=0$ Macdonald measure. On the other hand, it is known that $\mathbf{x}_N:=\lambda_N-N$ can be identified with the location of the $N$th particle in a certain discrete time $q$-TASEP started from the step initial configuration. The second construction we present is a coupling of this $q$-TASEP and the higher spin six vertex model (with the step Bernoulli boundary condition) along time-like paths providing an independent probabilistic explanation of the equality of $\mathfrak{h}(N+1,T)$ and $\mathbf{x}_N+N$ in distribution. Combined with the identification of averages of observables between the stochastic higher spin six vertex model and Schur measures (which are $t=q$ Macdonald measures) obtained recently in arXiv:1608.01553, this produces GUE Tracy--Widom asymptotics for a discrete time $q$-TASEP with the step initial configuration and special jump parameters., Comment: AMSLaTeX; 45 pages, 13 figures

Magnetotactic bacteria produce exquisitely ordered chains of uniform magnetite (Fe(3)O(4)) nanocrystals, and the use of the bacterial mms6 protein allows for the shape-selective synthesis of Fe(3)O(4) nanocrystals. Cobalt ferrite (CoFe(2)O(4)) nanoparticles, on the other hand, are not known to occur in living organisms. Here we report on the use of the recombinant mms6 protein in a templated synthesis of CoFe(2)O(4) nanocrystals in vitro. We have covalently attached the full-length mms6 protein and a synthetic C-terminal domain of mms6 protein to self-assembling polymers in order to template hierarchical CoFe(2)O(4) nanostructures. This new synthesis pathway enables facile room-temperature shape-specific synthesis of complex magnetic crystalline nanomaterials with particle sizes in the range of 40-100 nm that are difficult to produce using conventional techniques.

UNTIL recently the standard teaching in law and economics was that a doctrine of comparative negligence was inferior to the common-law rule that treated an injured party's contributory negligence as an absolute bar to tort recovery. The reasons for this position were twofold. First, it was generally believed that comparative negligence conveys no additional incentive for precautionary behavior by parties potentially involved in an accident. Second, it was urged that the adoption of comparative negligence introduces a deadweight loss (due to an inefficiently high outlay on precaution), which weighs against the "benefit" of more equitable loss distribution. That view of comparative negligence was first grounded in the informal analyses of Calabresi' and Posner.2 Thereafter, it was supported in formal analysis by Brown.3 More recently, it has been challenged in papers by Haddock and Curran4 and Cooter and Ulen.5 Cooter and Ulen show that Brown's analysis misconstrues the term "negligence" as applied to tort litigation; similarly, the conclusions of Calabresi and Posner were asserted (but not shown) to hinge on the very simple and highly restrictive pattern of effective accident-reducing behavior (here called "precaution technology") that they assume. Both Haddock and Curran and Cooter and Ulen find that in the presence of uncertainty

The safety of several strategies using novel adeno-associated viral (AAV) vectors (serotypes-1,-5,-7,and -8) to skeletal muscle of large animals have been hampered by the immune response to the transgene (Blood103: 85, 3303, and 3330). Dendritic cells (DC) are potent antigen-presenting cells that govern the immune responses. The involvement of proteases is critical to DC antigen processing and presentation. Proteases’ effects on cells are mediated by protease-activated receptor (PAR) a group of four G-protein-coupled receptors. Bone marrow-derived DC from PAR-2 knockout mice do not spontaneously develop to mature state and only do so upon stimulations of inflammatory signals, therefore, PAR-2 proved critical for DC activation. Work with selective PAR-2 agonists and knockout animals suggests a in vivo contribution of this receptor to several chronic inflammatory diseases and tumor development. In fact, small peptides functioning as PAR-2 antagonists are now being tested as anti-angiogenic agents. We sought to determine whether inhibiting specific targets on the T-cell activation cascade would provide a strategy to prevent the development of antibody following IM injection of AAV. To do this we evaluated the risk of inhibitior formation to clotting factor IX (FIX) in PAR-2 deficient mice compared with heterozygous (+/−) or normal (+/+) genotypes. Mice received IM injection of AAV-1 encoding human FIX (hFIX) at two different doses (low and high cohorts). FIX and antibody levels were monitored weekly. PAR-2(−/ −) mice(n=4) given the low dose exhibited circulating FIX levels of 500± 99ng/ml which remained stable for the duration of the experiment(10 weeks), and no antibody for FIX was detected. In three PAR-2(+/+) mice, FIX expression was transiently detected at week 2 followed by a period of 4 weeks with undetectable levels. This was due to the formation of FIX specific IgG-1 antibody, which results from activation of CD4+ T-cell mainly of Th2 subset, that peaked at week 6. These antibodies inhibit FIX clotting activity as determined by a functional assay at titre of 3–5.5BU (Bethesda Unit) in all 3 mice. High dose AAV-1 treated PAR-2(−/ −) mice(n=6) resulted in continuous expression of FIX(1,500±353ng/ml) in the absence of FIX antibody. In contrast, inhibitors of FIX were detected in all mice(5 per group) PAR-2(+/−) or PAR-2(+/+). All animals develop IgG-1 antibodies to FIX through 10 weeks of observation. At week 6 post-injection, FIX inhibitors were detected in 3/10 mice at levels of ~1 BU. Continuous follow-up showed that a decrease in antibody titers to FIX was associated with slowly increasing FIX antigen. In addition, splenocytes from PAR-2 (+/+) mice exhibit significant increase (p

A generalized version of the Modigliani-Hohn production smoothing model is analyzed, and two types or classes of theorem are proved. (Theorems 1 and 2): The planning horizon (defined as a minimal interval of sufficient length to yield optimal current decisions) depends critically on the existence of “bottleneck” conditions; in the case of the original M-H model, a bottleneck arises out of the inventory nonnegativity constraint, and it is here shown that an additional interesting bottleneck condition arises out of an inventory storage capacity constraint. Whether a particular type of bottleneck defines a horizon will depend, interestingly, on the terminal inventory condition that is imposed for the original optimization process. (Theorems 3 and 4): The sensitivity of horizon length to two economic parameters, the discount factor and the marginal storage cost, will depend on whether the horizon-determining bottleneck is due to a binding inventory capacity constraint, or a binding nonnegativity constraint. The capacity constraint will yield “perverse” horizon sensitivities first noted by Charnes, Dreze and Miller [Charnes, Abraham, Drèze, Jaques, Miller, Merton. 1966. Decision and horizon rules for stochastic planning problems: a linear example. Econometrica 34 307–330.] in their work on the warehousing problem. In light of these results, the importance of horizons as a programming concept can be questioned.

The smoothing of fluctuations in production and inventory has been handled successfully as a problem in servomechanisms: an optimal linear filter (production scheduling policy) balances costs of inventory fluctuation and costs of production fluctuation. This approach requires the system to respond (by making production rate changes) either continuously or at regular intervals: the usual assumption is that the cost of responding is proportional to the size of the response. This paper explores some reasons why the frequency of production changes may have to be controlled, and offers a new class of policies, called random walk policies, to accomplish this. One of these, the (a, b, c) policy, is investigated for stationary operating characteristics, and a specific example is provided to illustrate the technique of finding optimal values for policy parameters. Some of the characteristics of systems in which random walk inventory policies may be useful are discussed; and more general techniques for identifying the form of the optimal control policy are mentioned.

The possibility that some time series that arise in economics have error or innovation terms that come from infinite variance distributions throws doubt on most of the classical methods of analysis. The evidence in favor of infinite-variance is discussed and a variety of alternative explanations of the long-tailed property of observed distributions examined. Some of these alternative explanations are based on mixtures of distributions and suggest data-transformations that reduce or remove the problem. Clipping of the series seems to be a particularly useful technique and is applied to U.S. Treasury daily cash flow data.

CASE M. SPRENKLE (1969), in a refreshing departure from the elasticitygrubbing that constitutes most empirical work on money demand, examined predicted vs. reported levels of cash holdings in firms, using the equation derived by Baumol (1952) and Tobin (1956) as his predictor. Sprenkle concluded that compensating balance requirements, and not asset management decisions taken to cover transaction needs, are the most important data in explaining the amount of cash held by business firms. In this note, I argue that his results do not support his claim of showing "the uselessness of transaction demand models." Rather, they stem from (a) the inadequacy of the Baumol-Tobin (B-T) model as a representation of cash flows, and (b) the irrelevance of cash balance data contained in financial reports to empirical research on money holdings. I also show that Sprenkle's heavy reliance on the importance of compensating balances is misplaced. II. TRANSACTIONS DEMAND MODELS AS PREDICTORS He sets out to show "how little . . . [the B-T model] . . . really explains, how subject to error the results of the theory are, and how fruitless more sophisticated versions of the theory are apt to be." He shows that the model does a poor job of predicting the level of cash holdings in large business firms, and concludes with the obiter dictum that compensating balances determine the levels of business cash holdings. The Baumol-Tobin model depicts the cash flow as a sequence of k receipts per year, each one being followed by a steady stream of payments which just exhaust it. That representation is a priori unreasonable. A large part of any firm's cash transactions are with other firms, so few firms, if any, can show the cash flow pattern assumed in the B-T model. Also, direct evidence from a few firms shows a random mixture of odd-sized daily net receipts and payments. In those observed cases, the running mean of daily cash activity rapidly converges to a value close to zero; the daily flows have no significant underlying periodicity, and certainly no trend or "drift."' The B-T model, by contrast, assumes that the cash account level is extremely periodic, if it is left unadjusted. * NSF research support is gratefully acknowledged. This note is a spin-off from a longer paper that has been presented before several helpful audiences. Thanks are owed to R. Clower, M. Darby, J. Kindahl, A. Leijonhufvud, L. Meyer, R. Schmalensee, C. Sprenkle, and Jack M. Guttentag, for useful comments. The usual disclaimer on sources of error applies. ** Professor of Economics, University of California, San Diego. 1. One day is the ideal interval at which to observe cash flows, since returns on short-term securities can be realized on a daily basis, and banks monitor the demand deposit accounts of their customers once per day.

I. Introduction, 413. — II. A model of cash flows and the costs of cash management for business firms, 416; assumptions underlying the model, 417; optimal values of the policy parameters, 420; some properties of the solution, 423; implications for the demand for money by firms, 425; extension to allow for non-zero drift, 427.— III. The applicability of the model, 429. — Appendix, 433.

A cartel cannot control the price of a product unless all member firms adhere to the agreed price. If collulsive contracts are enforceable, price maintenance is straightforward; if contracts " in restrain-t of trade" are unenforceable, or illegal, this effective control of cheating is eliminated. Yet even without recourse to court-enforced sanctions, cartels have occasionally prospered.1 A cartel can survive by policing the members' behaviour, and threatening believable and punitive retaliation against cheating. In this article the requisite thoroughness of policing, and the deterrent powers of certain pricing strategies, are explored. In particular, it is shown that in an idealized homogeneous market, the cartel can make cheating unprofitable simply by threatening to establish a price that maximizes the profits of loyal member firms in the presence of cheaters. This pricing strategy is certainly believable; that it is also punitive to cheaters is shown in Sections 3-5. Another interesting pricing strategy is the matching of price cuts. This seems a natural course for a cartel confronted by a cheater: it was advocated by the Western Traffic Association in the U.S. when that cartel faced a -breakdown of its rate structure,2 and is suggested in recent theoretical literature as a viable means of enforcement.3 This pricing strategy is examined in Section 2.