bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclooxygenase‐2, prostaglandin E2 glycerol ester and nitric oxide are involved in muscarine‐induced presynaptic enhancement at the vertebrate neuromuscular junction
Authors: Lindgren Clark A. , Newman Zachary L. , Morford Jamie J. , Ryan Steven B. , Battani Kathryn A. , Su Zheng
Published: July 2013

Key points

The synapse between a nerve and muscle, called the neuromuscular junction (NMJ), undergoes a biphasic modulation, a decrease followed by an increase, when muscarinic acetylcholine receptors are continuously activated.

The initial depression is caused by the endocannabinoid 2‐arachidonylglycerol (2‐AG), which is synthesized in and released from the muscle; 2‐AG then activates cannabinoid receptors on the presynaptic nerve.

In the work presented here, we explored the mechanism responsible for the delayed enhancement, uncovering a role for the enzyme cyclooxygenase‐2 and locating it in the glial cells at the NMJ called perisynaptic Schwann cells (PSCs) where it converts 2‐AG into the glycerol ester of prostaglandin E2.

These results reveal a complex mechanism for regulating neurotransmitter release that involves the nerve, muscle and PSCs (i.e. the tripartite synapse) and may serve to ensure reliable neuromuscular transmission during periods of intense or long‐term activity.

Abstract  Previous work has demonstrated that activation of muscarinic acetylcholine receptors at the lizard neuromuscular junction (NMJ) induces a biphasic modulation of evoked neurotransmitter release: an initial depression followed by a delayed enhancement. The depression is mediated by the release of the endocannabinoid 2‐arachidonylglycerol (2‐AG) from the muscle and its binding to cannabinoid type 1 receptors on the motor nerve terminal. The work presented here suggests that the delayed enhancement of neurotransmitter release is mediated by cyclooxygenase‐2 (COX‐2) as it converts 2‐AG to the glycerol ester of prostaglandin E2 (PGE2‐G). Using immunofluorescence, COX‐2 was detected in the perisynaptic Schwann cells (PSCs) surrounding the NMJ. Pretreatment with either of the selective COX‐2 inhibitors, nimesulide or DuP 697, prevents the delayed increase in endplate potential (EPP) amplitude normally produced by muscarine. In keeping with its putative role as a mediator of the delayed muscarinic effect, PGE2‐G enhances evoked neurotransmitter release. Specifically, PGE2‐G increases the amplitude of EPPs without altering that of spontaneous miniature EPPs. As shown previously for the muscarinic effect, the enhancement of evoked neurotransmitter release by PGE2‐G depends on nitric oxide (NO) as the response is abolished by application of either NG‐nitro‐l‐arginine methyl ester (l‐NAME), an inhibitor of NO synthesis, or carboxy‐PTIO, a chelator of NO. Intriguingly, the enhancement is not prevented by AH6809, a prostaglandin receptor antagonist, but is blocked by capsazepine, a TRPV1 and TRPM8 receptor antagonist. Taken together, these results suggest that the conversion of 2‐AG to PGE2‐G by COX‐2 underlies the muscarine‐induced enhancement of neurotransmitter release at the vertebrate NMJ.
Operational Performance of the University of Minnesota 45 kWe High-Flux Solar Simulator
Authors: Krueger Katherine R. , Lipiński Wojciech , Davidson Jane H.
Published: July 2013

The University of Minnesota's high flux simulator delivers radiative power of approximately 9.2 kW over a Ø60 mm circular area located in the focal plane, corresponding to an average flux of 3200 kW m−2, with a peak flux of 7300 kW m−2.
Energy and Exergy Analyses of a New Triple-Staged Refrigeration Cycle Using Solar Heat Source
Authors: Khaliq Abdul , Kumar Rajesh , Dincer Ibrahim , Khalid Farrukh
Published: July 2013

In this paper, energy and exergy analyses of a new solar-driven triple-staged refrigeration cycle using Duratherm 600 oil as the heat transfer fluid are performed. The proposed cycle is an integration of absorption refrigeration cycle (ARC), ejector (EJE) refrigeration cycle (ERC), and ejector expansion Joule–Thomson (EJT) refrigeration cryogenic cycles which could produce refrigeration output of different magnitude at different temperature simultaneously. Both exergy destruction and losses in each component and hence in the overall system are determined to identify the causes and locations of the thermodynamic imperfection. Several design parameters, including the hot oil outlet temperature, refrigerant turbine inlet pressure, and the evaporator temperature of ERC and EJT cycle are also tested to evaluate their effects on energy and exergy performance. It is observed that largest contribution to cycle irreversibility comes from the central receiver and heliostat field with the heat recovery vapor generator (HRVG), condenser, and ejector of ERC itself also contributing considerably. The exergy efficiency of the solar-driven triple-staged refrigeration cycle is 4% which is much lower than its energy efficiency of 10%, respectively. The results clearly reveal that thermodynamic investigations based on energy analysis alone cannot legitimately be complete unless the exergy concept becomes a part of the analysis.
A Computational Aid for Problem Formulation in Early Conceptual Design
Authors: MacLellan Christopher J. , Langley Pat , Shah Jami , Dinar Mahmoud
Published: July 2013

Conceptual design is a high-level cognitive activity that draws upon distinctive human mental abilities. An early and fundamental part of the design process is problem formulation, in which designers determine the structure of the problem space they will later search. Although many tools have been developed to aid the later stages of design, few tools exist that aid designers in the early stages. In this paper, we describe Problem Formulator, an interactive environment that focuses on this stage of the design process. This tool has representations and operations that let designers create, visualize, explore, and reflect on their formulations. Although this process remains entirely under the user's control, these capabilities make the system well positioned to aid the early stages of conceptual design.
Design Optimization of Complex Hydromechanical Transmissions
Authors: Pettersson Karl , Krus Petter
Published: July 2013

Demands for higher fuel efficiency for off-highway applications motivate manufacturers to replace existing drive transmissions with more complex, high-efficiency transmissions. Increased intelligence and more advanced architectures are, however, more difficult to design and prototype. This leads to longer product development processes and a greater need for early product evaluation. The great variety of existing concepts also requires a methodology to support the choice of architecture. This paper proposes a design methodology for complex hydromechanical transmissions based on optimization. The main objective is to maximize energy efficiency and adapt the design to suit the typical operating behavior of the application. The methodology is also implemented on a multiple mode transmission concept sui for a heavy wheel loader application. It is shown that the design of the gearbox heavily influences the energy consumption and the necessity to use optimization when designing the gearbox.
Updating Kriging Surrogate Models Based on the Hypervolume Indicator in Multi-Objective Optimization
Authors: Shimoyama Koji , Sato Koma , Jeong Shinkyu , Obayashi Shigeru
Published: July 2013

This paper presents a comparison of the criteria for updating the Kriging surrogate models in multi-objective optimization: expected improvement (EI), expected hypervolume improvement (EHVI), estimation (EST), and those in combination (EHVI + EST). EI has been conventionally used as the criterion considering the stochastic improvement of each objective function value individually, while EHVI has recently been proposed as the criterion considering the stochastic improvement of the front of nondominated solutions in multi-objective optimization. EST is the value of each objective function estimated nonstochastically by the Kriging model without considering its uncertainties. Numerical experiments were implemented in the welded beam design problem, and empirically showed that, in an unconstrained case, EHVI maintains a balance between accuracy, spread, and uniformity in nondominated solutions for Kriging-model-based multiobjective optimization. In addition, the present experiments suggested future investigation into techniques for handling constraints with uncertainties to enhance the capability of EHVI in constrained cases.
Reversing Roles for Innervation
Authors: Ferrarelli Leslie K.
Published: July 2013

Tumor necrosis factor (TNF) receptor in target tissues may guide the innervation of TNF-positive sympathetic axons in postnatal development.
Role of 6-Gingerol in Reduction of Cholera Toxin Activity
In Vitro
and
In Vivo
Authors: Saha Pallashri , Das Bornita , Chaudhuri Keya
Published: July 2013

Vibrio cholerae
is one of the major bacterial pathogens responsible for the devastating diarrheal disease called cholera. Chemotherapy is often used against
V. cholerae
infections; however, the emergence of
V. cholerae
with multidrug resistance (MDR) toward the chemotherapeutic agents is a serious clinical problem. This scenario has provided us with the impetus to look into herbal remediation, especially toward blocking the action of cholera toxin (CT). Our studies were undertaken to determine the antidiarrheal potential of 6-gingerol (6G) on the basis of its effect on CT, the virulence factor secreted by
V. cholerae
. We report here that 6G binds to CT, hindering its interaction with the GM1 receptor present on the intestinal epithelial cells. The 50% inhibitory concentration (IC
50
) was determined to be 10 μg/ml. The detailed mechanistic study was conducted by enzyme-linked immunosorbent assay (ELISA), fluorescence spectroscopy, and isoelectric focusing. These results were validated with
in vitro
studies performed with the CHO, HeLa, and HT-29 cell lines, whereas a rabbit ileal loop assay was done to estimate the
in vivo
action, which confirms the efficacy of 6G in remediation of the choleragenic effects of CT. Thus, 6G can be an effective adjunctive therapy with oral rehydration solution for severe CT-mediated diarrhea.
In Vitro
Antifungal Activity of Naftifine Hydrochloride against Dermatophytes
Authors: Ghannoum M. , Isham N. , Verma A. , Plaum S. , Fleischer A. , Hardas B.
Published: July 2013

The incidence of superficial dermatophytoses is high in developed countries, and there remains a need for effective topical antifungals. In this study, we evaluated the
in vitro
antifungal activity of naftifine hydrochloride, the active ingredient in naftifine hydrochloride cream and gel 1% and 2%, against dermatophytes. The MICs and minimum fungicidal concentrations (MFCs) of naftifine hydrochloride against 350 clinical strains, including
Trichophyton rubrum
,
T. mentagrophytes
,
T. tonsurans
,
Epidermophyton floccosum
, and
Microsporum canis
, were determined using the CLSI methodology. Subsets from this test panel were subsequently tested in a time-kill assay at 0.125×, 0.25×, 0.5×, and 1× the MFC for each isolate. CFU counts were performed over a period of 48 h of incubation. Additionally, in order to determine the potential for resistance development, six strains were subjected to 15 serial passages in concentrations higher than the MIC for each strain. MICs were determined following each passage. The MIC range against the dermatophyte isolates tested was 0.015 to 1.0 μg/ml, with naftifine hydrochloride being fungicidal against 85% of the
Trichophyton
species. The time-kill assay showed dose-dependent activity, with the greatest reduction in the numbers of CFU corresponding to the highest drug concentration. There was no increase in MIC for any strains following repeated exposure to naftifine hydrochloride. Naftifine hydrochloride demonstrated potent activity against all dermatophytes tested, and none of the isolates within this test panel demonstrated the potential for the development of resistance. Thus, future clinical studies of naftifine hydrochloride against dermatophytes may be warranted for the treatment of superficial dermatophytoses.
Identification of Genes Involved in Neisseria meningitidis Colonization
Authors: Jamet Anne , Euphrasie Daniel , Martin Patricia , Nassif Xavier
Published: July 2013

Neisseria meningitidis
is a worldwide cause of meningitis and septicemia leading at least to 50,000 deaths every year. Nevertheless,
N. meningitidis
is also a commensal bacterium that asymptomatically colonizes the epithelial cells of the nasopharynx of 10 to 30% of healthy individuals. Occasionally,
N. meningitidis
crosses the nasopharyngeal barrier and enters the bloodstream. During bacteremia,
N. meningitidis
may adhere to endothelial cells of brain vessels and invade meninges. To identify the genes required for meningococcal host colonization, we screened a signature-tagged transposon mutagenesis library using an innovative
in vitro
colonization model in order to identify mutants displaying decreased capacity to colonize human epithelial cells. Approximately 1,600 defined insertion mutants of invasive serogroup C strain NEM8013 were screened. Candidate mutants were tested individually for quantification of bacterial biomass with confocal microscope and COMSTAT software. Five mutants were demonstrated to exhibit significantly decreased colonization ability. The identified genes, including
narP
and
estD
, appeared to be involved in adaptation to hypoxic conditions and stress resistance. Interestingly, the genes
fadD1
,
nnrS
, and
NMV_2034
(encoding a putative thioredoxin), prior to this study, had not been shown to be involved in colonization. Therefore, we provide here insights into the meningococcal functions necessary for the bacterium to adapt to growth on host cells.
Identification and Characterization of Cryptosporidium parvum Clec, a Novel C-Type Lectin Domain-Containing Mucin-Like Glycoprotein
Authors: Bhalchandra Seema , Ludington Jacob , Coppens Isabelle , Ward Honorine D.
Published: July 2013

Cryptosporidium
species are waterborne apicomplexan parasites that cause diarrheal disease worldwide. Although the mechanisms underlying
Cryptosporidium
-host cell interactions are not well understood, mucin-like glycoproteins of the parasite are known to mediate attachment and invasion
in vitro
. We identified
C. parvum
Clec (
Cp
Clec), a novel mucin-like glycoprotein that contains a C-type lectin domain (CTLD) and has orthologs in
C. hominis
and
C. muris
. CTLD-containing proteins are ligand-binding proteins that function in adhesion and signaling and are present in a wide range of organisms, from humans to viruses. However, this is the first report of a CTLD-containing protein in protozoa and in
Apicomplexa. Cp
Clec is predicted to be a type 1 membrane protein, with a CTLD, an O-glycosylated mucin-like domain, a transmembrane domain, and a cytoplasmic tail containing a YXXϕ sorting motif. The predicted structure of
Cp
Clec displays several characteristics of canonical CTLD-containing proteins, including a long loop region hydrophobic core associated with calcium-dependent glycan binding as well as predicted calcium- and glycan-binding sites.
Cp
Clec expression during
C. parvum
infection
in vitro
is maximal at 48 h postinfection, suggesting that it is developmentally regulated. The 120-kDa mass of native
Cp
Clec is greater than predicted, most likely due to O-glycosylation.
Cp
Clec is localized to the surface of the apical region and to dense granules of sporozoites and merozoites. Taken together, these findings, along with the known functions of
C. parvum
mucin-like glycoproteins and of CTLD-containing proteins, strongly implicate a significant role for
Cp
Clec in
Cryptosporidium
-host cell interactions.
Edwardsiella tarda Ivy, a Lysozyme Inhibitor That Blocks the Lytic Effect of Lysozyme and Facilitates Host Infection in a Manner That Is Dependent on the Conserved Cysteine Residue
Authors: Wang Chong , Hu Yong-hua , Sun Bo-guang , Li Jun , Sun Li
Published: July 2013

Edwardsiella tarda
is a Gram-negative bacterial pathogen with a broad host range that includes fish and humans. In this study, we examined the activity and function of the lysozyme inhibitor Ivy (named Ivy
Et
) identified in the pathogenic
E. tarda
strain TX01. Ivy
Et
possesses the Ivy signature motif CKPHDC in the form of
82
CQPHNC
87
and contains several highly conserved residues, including a tryptophan (W55). For the purpose of virulence analysis, an isogenic TX01 mutant, TXivy, was created. TXivy bears an in-frame deletion of the

ivy
Et

gene. A live infection study in a turbot (
Scophthalmus maximus
) model showed that, compared to TX01, TXivy exhibited attenuated overall virulence, reduced tissue dissemination and colonization capacity, an impaired ability to replicate in host macrophages, and decreased resistance against the bactericidal effect of host serum. To facilitate functional analysis, recombinant Ivy
Et
(rIvy) and three mutant proteins, i.e., rIvyW55A, rIvyC82S, and rIvyH85D, which bear Ala, Ser, and Asp substitutions at W55, C82, and H85, respectively, were prepared.
In vitro
studies showed that rIvy, rIvyW55A, and rIvyH85D were able to block the lytic effect of lysozyme on a Gram-positive bacterium, whereas rIvyC82S could not do so. Likewise, rIvy, but not rIvyC82S, inhibited the serum-facilitated killing effect of lysozyme on
E. tarda
.
In vivo
analysis showed that rIvy, but not rIvyC82S, restored the lost pathogenicity of TXivy and enhanced the infectivity of TX01. Together these results indicate that Ivy
Et
is a lysozyme inhibitor and a virulence factor that depends on the conserved C82 for biological activity.
Donor CD8+T Cells Prevent Toxoplasma gondii De-Encystation but Fail To Rescue the Exhausted Endogenous CD8+T Cell Population
Authors: Bhadra Rajarshi , Cobb Dustin A. , Khan Imtiaz A.
Published: July 2013

Functional exhaustion of CD8+T cells due to increased expression of inhibitory molecule PD-1 (Programmed Death-1) causes reactivation of latent disease during later phases of chronic toxoplasmosis. Onset of disease recrudescence results in decreased parasite cyst burden concomitant with parasites undergoing stage conversion from a primarily encysted, quiescent bradyzoite to a fast-replicating, highly motile tachyzoite. Thus, reduced cyst burden is one of the early hallmarks of disease recrudescence. This was further validated by depleting gamma interferon (IFN-γ), a cytokine known to control latent toxoplasmosis, in chronically infected prerecrudescent mice. Since CD8+T cells (an important source of IFN-γ) lose their functionality during the later phases of chronic toxoplasmosis, we next examined if adoptive transfer of functional CD8+T cells from acutely infected donors to the chronically infected prerecrudescent hosts could impede parasite de-encystation and rescue exhausted CD8+T cells. While the transfer of immune CD8+T cells temporarily restricted the breakdown of cysts, the exhausted endogenous CD8+T cell population was not rescued. Over time, the donor population got deleted, resulting in parasite de-encystation and host mortality. Considering that donor CD8+T cells fail to become long-lived, one of the cardinal features of memory CD8+T cells, it bears the implication that memory CD8 differentiation is impaired during chronic toxoplasmosis. Moreover, our data strongly suggest that while adoptive immunotherapy can prevent parasite de-encystation transiently, reduced antigen burden in the chronic phase by itself is insufficient for rescue of exhausted CD8+T cells. The conclusions of this study have profound ramifications in designing immunotherapeutics against chronic toxoplasmosis.
Necrotising fasciitis of odontogenic origin
Authors: Chunduri Nagendra Srinivas , Madasu Krishnaveni , Tammannavar Praveen Shrimant , C Pushpalatha
Published: July 2013

Necrotising fasciitis (NF) is a rare infection of the fascial planes, which is less common in head and neck, because of the rarity and higher vascularity in the region. We report a case of necrotising fasciitis in a 43-year-old man, arising from a dental infection treated successfully by early diagnosis, prompt surgical management, antibiotic therapy and adjunctive hyperbaric oxygen (HBO) therapy. The diagnosis of descending NF must always be considered in a patient who presents with a history of oropharyngeal infection with evidence of neck swelling, chest pain, and dyspnea or respiratory distress. Aggressive surgical debridement of all involved tissue along with intravenous antibiotic therapy should be initiated before aerobic and anaerobic cultures are obtained. HBO may also be of some benefit in the treatment of this potentially fatal infection.
Use of IABP in contrast media-induced anaphylactic shock: the ultimate lifesaver
Authors: Alam Rajib , Anantharaman Rajaram
Published: July 2013

Anaphylactic reaction to contrast media during selective coronary angiography is a rare occurrence. It can be occasionally resistant to medical treatment leading to cardiovascular collapse and death. The use of intra-aortic balloon pump (IABP) counter-pulsation when the supportive medical treatment fails during anaphylactic shock is not well documented in the literature. We report a case of a severe contrast media-induced anaphylactic shock which failed to respond to the supportive medical management and the timely insertion of IABP for further circulatory support that prevented death in a patient who had an elective diagnostic coronary angiography. The clinical diagnosis of anaphylaxis was challenging at the onset of shock as the typical rash developed after a few minutes.
Synchronous colorectal neoplasms in ulcerative pancolitis of 6 years duration: pathological and molecular heterogeneity
Authors: BM Shivakumar , Rao Lakshmi , K Satyamoorthy , Pai Ganesh C
Published: July 2013

Colorectal cancer (CRC) complicating ulcerative colitis (UC) accounts for about 1% of all cases of CRC. Such tumours develop from pre-existing foci of dysplasia in patients with extensive and long-standing UC. We report a case of UC-associated synchronous CRC and foci of high-grade dysplasia with an additional malignant focus in the appendix in a female patient after only 6 years of pancolitis who did not have other risk factors for the development of complications. The multiplicity and the timings of the early changes noted suggest that long-standing inflammation in UC randomly damages multiple genes in epithelial cells known to contribute to colorectal carcinogenesis. Current findings also support a molecular and pathological heterogeneity during multiclonal origin of synchronous tumours whereby differences occur at various sites that were absent during the initial stages of the disease.
Spatial modeling of Bering Sea walleye pollock with integrated age-structured assessment models in a changing environment
Authors: Hulson Peter-John F. , Quinn Terrance J. , Hanselman Dana H. , Ianelli James N.
Published: July 2013

Climate change may affect the spatial distribution of fish populations in ways that would affect the accuracy of spatially aggregated age-structured assessment models. To evaluate such scenarios, spatially aggregated models were compared with spatially explicit models using simulations. These scenarios were based on hypothetical climate-driven distribution shifts and reductions in mean recruitment of walleye pollock (Gadus chalcogrammus) in the eastern Bering Sea. Results indicate that biomass estimates were reasonably accurate for both types of estimation models and precision improved with the inclusion of tagging data. Bias in some aggregated model scenarios could be attributed to unaccounted-for process errors in annual fishing mortality rates and was reduced when estimating effective sample size or time-varying selectivity. Spatially explicit models that allow estimation of variability in movement and ontogenetic parameters (specified as a random walk process) were shown to be feasible, whereas models that misspecified ontogenetic movement and climate change effects resulted in biased biomass and movement parameter estimates. These results illustrate that more complex models may characterize processes better but may be less robust for management advice.
The interplay between dispersal and gene flow in anadromous Arctic char (Salvelinus alpinus): implications for potential for local adaptation
Authors: Moore Jean-Sébastien , Harris Les N. , Tallman Ross F. , Taylor Eric B.
Published: July 2013

Dispersal can influence the process of local adaptation, particularly when the dispersers successfully breed in the non-natal habitat. Anadromous Arctic char (Salvelinus alpinus) display a complex migratory behaviour that makes the distinction between breeding and nonbreeding dispersal especially important. This species does not reproduce every year, but individuals must migrate to fresh water to overwinter such that a large proportion of fish running up-river are not in breeding condition and have no potential for gene flow. We used a genetic assignment approach to identify dispersers among populations of char from Baffin Island, Canada. Estimates of dispersal varied between 15.8% and 25.5% depending on the assignment method, suggesting that Arctic char disperse at a higher rate than other salmonids. Nonbreeding individuals were more likely to use non-natal habitats than breeding individuals, thus resulting in estimates of dispersal that overestimate the potential for gene flow among populations. Finally, we parameterized a population genetic model showing that gene flow is probably sufficiently low to allow for local adaptation among populations, given realistic selection coefficients. Our results underscore the importance of understanding patterns of dispersal to appropriately evaluate their potential consequences for local adaptation and management.
SOME REMARKS ON EVOLUTIONARY STABILITY IN MATRIX GAMES
Authors: MALLIKARJUNA RAO K. S. , SHAIJU A. J.
Published: July 2013

In this article, we revisit evolutionary stability in matrix games. We provide a new direct proof to characterize a pure evolutionarily stable strategy (ESS), in games with exactly two pure strategies, as a strategy that is evolutionarily stable against multiple mutations. This direct proof yields generalizations to k × k games which explains why such a characterization is not possible in general. Furthermore, we prove other necessary/sufficient conditions for evolutionary stability against multiple mutations.
AVERAGE RULES FOR COOPERATIVE TU GAMES
Authors: SUGUMARAN A. , THANGARAJ V. , RAVINDRAN G.
Published: July 2013

In this paper, we propose a new single valued rule based on the concept of fair division for all cooperative transferable utility (TU) games. In any cooperative TU game, primarily the coalitions that are likely to form are identified and each such coalition is fixed with a payoff vector based on the notion of fairness. The value of the single valued rule is obtained from the collection of all coalition structures consisting of the coalitions that are likely to form. The uniqueness of the new rule is followed by its existence and computational simplicity for all TU games. Finally, a linear average rule is defined, and some of its properties are discussed.
IMPACT OF RETAILER COMPETITION ON MANUFACTURER'S DECISIONS AND PROFITS AT EQUILIBRIUM
Authors: HOTKAR PARSHURAM S. , MOHAN USHA
Published: July 2013

As most of the supply chains in practice are decentralized, a key issue in supply chain management is to study the coordination of supply chain. The interactions among players are typically of two types, viz. vertical competition and horizontal competition. We use a game theoretic framework to analyze a two-stage supply chain. The supply chain is modeled as a Stackelberg game with a manufacturer as leader and multiple retailers as followers. We consider multiple retailers competing on quantities (Cournot competition) and study its impact on manufacturer's equilibrium decisions and profits. We show that the wholesale price contract does not achieve Nash equilibrium when retailers offer uniform pricing. On the other hand, in case of perfect price discrimination we prove the existence of unique Nash equilibrium in both deterministic and stochastic demand set-up. Under stochastic demand set-up, we consider information asymmetry between the manufacturer and retailers with respect to demand signal. Furthermore, we show the retailers' selling effort boost up the sales. As variance of sales can hurt the manufacturer's production decisions badly, we conjecture that the manufacturer can offer a retailer incentive contract which can manipulate retailers' equilibrium decision.
ON FULLY SEMIMONOTONE MATRICES
Authors: MURTHY G. S. R. , PARTHASARATHY T. , SRIDHAR R.
Published: July 2013

The class of fully semimonotone matrices is well known in the study of the linear complementarity problem. Stone [(1981) Ph.D. thesis, Dept. of Operations Research, Stanford University, Stanford, CA] introduced this class and conjectured that the principal minors of any fully semimonotone Q0-matrix are non-negative. While the problem is still open, Murthy and Parthasarathy [(1998) Math. Program.82, 401–411] introduced the concept of incidence using which they proved that the principal minors of any matrix in the class of fully copositive Q0-matrices, a subclass of fully semimonotone Q0-matrices, are non-negative. In this paper, we study some properties of fully semimonotone matrices in connection with incidence. The main result of the paper shows that Stone's conjecture is true in the special case where the complementary cones have no partial incidence. We also present an interesting characterization of Q0 for matrices with a special structure. This result is very useful in checking whether a given matrix belongs to Q0 provided it has the special structure. Several examples are discussed in connection with incidence and Q0 property.
DEGRADATION EFFECT OF SEAWATER ON THE LONG-TERM DYNAMIC BEHAVIOR OF ARTIFICIALLY CEMENTED SAND
Authors: LI BO , CAI YUANQIANG , ZENG XIANGWU , PAN LINYOU
Published: July 2013

The dynamic behavior of lightly cemented sand under long-term seawater attack was evaluated in this study. Resonant column and cyclic triaxial tests were employed to investigate the evolution of the shear modulus and damping ratio of cemented sand with respect to soaking period (SP), confining pressure, and cement content (CC). The results of this study show that the cementation of the sand is affected by soaking in seawater to a greater extent than by soaking in tap water. The shear modulus of the cemented sand soaked in seawater was smaller than that of the cemented sand soaked in tap water. The damping ratio increased significantly, as the SP increased and was greater for the cemented sand soaked in seawater than for the cemented sand soaked in tap water. The dynamic behavior of nonhomogenous specimens was examined. Crystallization of salts could be clearly observed and probably explains the evolution of the dynamic behavior of the cemented sand. Finally, the shear modulus was fitted using Rollins' Law [Rollins et al., 1998], which demonstrates that the parameters used in the equation can be reasonably fitted linearly over a range of SPs.
A Tax-Based Estimate of the Elasticity of Intertemporal Substitution
Authors: Gruber Jonathan
Published: July 2013

One of the most important behavioral parameters in macroeconomics is the elasticity of intertemporal substitution (EIS). Starting with the seminal work of Hall (Hall, R., 1978, Stochastic Implications of the Life Cycle — Permanent Income Hypothesis: Theory and Evidence, Journal of Political Economy 86, 971–987), researchers have used an Euler equation framework to estimate the EIS, relating the growth rate of consumption to the after-tax interest rate facing consumers. This large literature has, however, produced very mixed results, perhaps due to an important limitation: The impact of the interest rate on consumption or savings is identified by time-series movements in interest rates. Yet the factors that cause time-series movements in interest rates may themselves be correlated with consumption or savings decisions. I address this problem by using variation across individuals in the capital income tax rate. Conditional on observable characteristics of individuals, tax rate movements cause exogenous shifts in the after-tax interest rate. Using data on total non-durable consumption from the Consumer Expenditure Survey over two decades, I estimate a surprisingly high EIS of two. This finding is robust to a variety of specification checks.
A review of geomorphic processes and landforms in the Dry Valleys of southern Victoria Land: implications for evaluating climate change and ice-sheet stability
Authors: Marchant D. R. , Mackay S. L. , Lamp J. L. , Hayden A. T. , Head J. W.
Published: July 2013

The Dry Valleys are subdivided into three microclimate zones on the basis of summertime measurements of atmospheric temperature, soil moisture, relative humidity and wind-speed/ direction. Subtle variations in these climate parameters result in considerable differences in process geomorphology and in the development of unique landforms within each zone. The mapped zones include a coastal thaw zone, an inland mixed zone and a stable upland zone. Landforms within each zone are subdivided into macroscale features (e.g. valleys, slopes and gullies), mesoscale features (e.g. polygons and viscous-flow features) and microscale features (e.g. rock and near-surface soil features, including the effects of salt weathering, wind erosion and pitting). We present a review of landscape development in the Dry Valleys with implications for long-term climate change and ice-sheet stability. Chronological control is afforded by
40
Ar/
39
Ar dating of volcanic ash-fall deposits and cosmogenic nuclide analyses of surface boulders. Collectively, the data call for persistent cold and dry conditions in the stable upland zone for approximately the last 14 Ma, although some level of climatic amelioration and landform modification may have occurred within low-lying regions and in the inland mixed zone.
Provenance of Pleistocene sediments from Site U1359 of the Wilkes Land IODP Leg 318 – evidence for multiple sourcing from the East Antarctic Craton and Ross Orogen
Authors: Pant N. C. , Biswas P. , Shrivastava Prakash K. , Bhattacharya S. , Verma Kamlesh , Pandey Mayuri ,   Iodp Expedition 318 Scientific Party
Published: July 2013

Site U1359 is located on the eastern levée of the Jussieau submarine channel on the Wilkes Land margin, East Antarctica. The upper approximately 60 m of the sediment core records more than 2.5 Ma of the depositional history. Present work focuses on inferring provenance from the heavy mineral fraction from the Pleistocene sediments. Clay and non-clay fractions were characterized using X-ray diffraction and micro-beam techniques. Metamorphic minerals including orthopyroxene, high-Ca garnet and high-Ti biotite indicate a source in a high-grade metamorphic terrain. Mixing from a low- to medium-grade metamorphic component is also indicated. Several basaltic rock fragments, showing mineralogical affinities to the Ferrar volcanic province in the Ross Sea sector, are present. The metamorphic component is correlatable with the Proterozoic East Antarctic cratonic shield component. Ordovician–Silurian ages for the euhedral xenotime and monazite, coupled with the Ferrar equivalent basalts, indicate an additional sediment source from the Ross Orogen along with that from the craton.
The geological and tectonic evolution of the Transantarctic Mountains: a review
Authors: Elliot David H.
Published: July 2013

The development of the Transantarctic Mountains was initiated with the rifting of Rodinia and the formation of a late Neoproterozoic passive continental margin. In Cambrian time this rift setting evolved into an active margin with batholith emplacement into deformed and lightly metamorphosed upper Neoproterozoic–Cambrian strata, creating the Ross Orogen. Denudation and erosion of the Ross Orogen led to the formation of the pre-Devonian Kukri Erosion Surface on which Devonian quartzose sandstones accumulated in a continental setting. Palaeozoic magmatic arcs were intermittently active along the distal Panthalassan margin. Intra-cratonic basins developed in Permian time, one of which evolved into a foreland basin clearly related to a Permo-Triassic magmatic arc. The Palaeozoic–early Mesozoic arcs can be traced into both Australasia and South America. In Early Jurassic time the margin migrated outboard simultaneously with the advent of proximal silicic volcanism, emplacement of the Ferrar Large Igneous Province and Gondwana break-up. These events marked the onset of plate margin reorganization, and with it the early uplift of the Transantarctic Mountains. During Cretaceous and later time episodic uplift of the Transantarctic Mountains was accompanied by formation of a major crustal and lithospheric boundary marking the edge of the East Antarctic craton and the regions of crustal attenuation in the Ross (West Antarctic Rift System) and Weddell embayments.
Periglacial processes and landforms of the Antarctic: a review of recent studies and directions
Authors: Hall Kevin
Published: July 2013

The wide range of periglacial environments of the Antarctic, from the wet, mild oceanic sub-Antarctic through to the cold, dry continent, provides not only an extensive modern laboratory, but also one that offers insights into conditions in the Northern Hemisphere at the height of the last glacial, is an analogue for periglacial conditions on other planets, and can be used for monitoring climatic change. Almost the whole known suite of periglacial landforms is present. Recent research directions show strong linkages between the biotic components and the abiotic responses, offering new insights into periglacial synergies and hence landform development. Other new directions are those of using the Antarctic as an analogue for periglacial conditions on Mars, and multinational undertakings monitoring permafrost and active layer changes. During the past three decades there have been a number of reviews of periglacial landforms and processes for both the area as a whole as well as for specific locations or regions. Here information regarding material post-dating the most recent reviews is provided and an attempt is made to highlight new directions and findings. This broad-based review provides a foundation for more detailed accounts on some of the periglacial attributes provided in other papers within these volumes.
Depth synthesis and local warps for plausible image-based navigation
Authors: Chaurasia Gaurav , Duchene Sylvain , Sorkine-Hornung Olga , Drettakis George
Published: July 2013

Modern camera calibration and multiview stereo techniques enable users to smoothly navigate between different views of a scene captured using standard cameras. The underlying automatic 3D reconstruction methods work well for buildings and regular structures but often fail on vegetation, vehicles, and other complex geometry present in everyday urban scenes. Consequently, missing depth information makes Image-Based Rendering (IBR) for such scenes very challenging. Our goal is to provide
plausible
free-viewpoint navigation for such datasets. To do this, we introduce a new IBR algorithm that is robust to missing or unreliable geometry, providing plausible novel views even in regions quite far from the input camera positions. We first oversegment the input images, creating superpixels of homogeneous color content which often tends to preserve depth discontinuities. We then introduce a
depth synthesis
approach for poorly reconstructed regions based on a graph structure on the oversegmentation and appropriate traversal of the graph. The superpixels augmented with synthesized depth allow us to define a local shape-preserving warp which compensates for inaccurate depth. Our rendering algorithm blends the warped images, and generates plausible image-based novel views for our challenging target scenes. Our results demonstrate novel view synthesis in real time for multiple challenging scenes with significant depth complexity, providing a convincing immersive navigation experience.
CompCertTSO
Authors: Ševčík Jaroslav , Vafeiadis Viktor , Zappa Nardelli Francesco , Jagannathan Suresh , Sewell Peter
Published: July 2013

In this article, we consider the semantic design and verified compilation of a C-like programming language for concurrent shared-memory computation on x86 multiprocessors. The design of such a language is made surprisingly subtle by several factors: the relaxed-memory behavior of the hardware, the effects of compiler optimization on concurrent code, the need to support high-performance concurrent algorithms, and the desire for a reasonably simple programming model. In turn, this complexity makes verified compilation both essential and challenging.

We describe ClightTSO, a concurrent extension of CompCert’s Clight in which the TSO-based memory model of x86 multiprocessors is exposed for high-performance code, and CompCertTSO, a formally verified compiler from ClightTSO to x86 assembly language, building on CompCert. CompCertTSO is verified in Coq: for any well-behaved and successfully compiled ClightTSO source program, any permitted observable behavior of the generated assembly code (if it does not run out of memory) is also possible in the source semantics. We also describe some verified fence-elimination optimizations, integrated into CompCertTSO.
Revisiting “forward node-selecting queries over trees”
Authors: Cheney James
Published: July 2013

In “Forward Node-Selecting Queries over Trees,” Olteanu [2007] gives three rewriting systems for eliminating reverse XPath axis steps from node-selecting queries over trees, together with arguments for their correctness and termination for a large class of input graphs, including cyclic ones. These proofs are valid for tree or acyclic formulas, but two of the rewrite systems (
TRS
2
and
TRS
3
) do not terminate on cyclic graphs; that is, there are infinite rewrite sequences that never yield a normal form. We investigate the reasons why the termination arguments do not work for general cyclic formulas, and develop alternative algorithms that can be used instead. We prove that
TRS
2
is weakly normalizing, while
TRS
3
is not weakly normalizing, but it can be extended to a weakly normalizing system
TRS
3
○
. The algorithms and proof techniques illustrate unforeseen subtleties in the handling of cyclic queries.
Check before storing
Authors: Bianchi Giuseppe , Detti Andrea , Caponi Alberto , Blefari Melazzi Nicola
Published: July 2013

In some network and application scenarios, it is useful to cache content in network nodes on the fly, at line rate. Resilience of in-network caches can be improved by guaranteeing that all content therein stored is valid. Digital signatures could be indeed used to verify content integrity and provenance. However, their operation may be much slower than the line rate, thus limiting caching of cryptographically verified objects to a small subset of the forwarded ones. How this affects caching performance? To answer such a question, we devise a simple analytical approach which permits to assess performance of an LRU caching strategy storing a randomly sampled subset of requests. A key feature of our model is the ability to handle traffic beyond the traditional Independent Reference Model, thus permitting us to understand how performance vary in different temporal locality conditions. Results, also verified on real world traces, show that content integrity verification does not necessarily bring about a performance penalty; rather, in some specific (but practical) conditions, performance may even improve.
Workshop on internet economics (WIE2012) report
Authors: claffy kc , Clark David
Published: July 2013

On December 12-13 2012, CAIDA and the Massachusetts Institute of Technology (MIT) hosted the (invitation-only) 3rd interdisciplinary Workshop on Internet Economics (WIE) at the University of California's San Diego Supercomputer Center. The goal of this workshop series is to provide a forum for researchers, commercial Internet facilities and service providers, technologists, economists, theorists, policy makers, and other stakeholders to empirically inform current and emerging regulatory and policy debates. The theme for this year's workshop was "Definitions and Data". This report describes the discussions and presents relevant open research questions identified by participants. Slides presented at the workshop and a copy of this final report are available at [2]
A Noise-Insensitive Semi-Active Air Suspension for Heavy-Duty Vehicles with an Integrated Fuzzy-Wheelbase Preview Control
Authors: Xie Zhengchao , Wong Pak Kin , Zhao Jing , Xu Tao , Wong Ka In , Wong Hang Cheong
Published: July 2013

Semi-active air suspension is increasingly used on heavy-duty vehicles due to its capabilities of consuming less power and low cost and providing better ride quality. In this study, a new low cost but effective approach, fuzzy-wheelbase preview controller with wavelet denoising filter (FPW), is developed for semi-active air suspension system. A semi-active suspension system with a rolling lobe air spring is firstly modeled and a novel front axle vertical acceleration-based road prediction model is constructed. By adopting a sensor on the front axle, the road prediction model can predict more reliable road information for the rear wheel. After filtering useless signal noise, the proposed FPW can generate a noise-insensitive control damping force. Simulation results show that the ride quality, the road holding, the handling capability, the road friendliness, and the comprehensive performance of the semi-active air suspension with FPW outperform those with the traditional active suspension with PID-wheelbase preview controller (APP). It can also be seen that, with the addition of the wavelet filter, the impact of sensor noise on the suspension performance can be minimized.
Peanut Cultivar Response to Flumioxazin Applied Preemergence and Imazapic Applied Postemergence
Authors: Grichar W. J. , Dotray P. A. , Baring M. R.
Published: July 2013

Field studies were conducted during 2009 and 2010 in Texas at Yoakum and Lamesa to determine peanut cultivar response to flumioxazin applied preemergence (0.053, 0.107, and 0.214 kg ai ha−1) and imazapic applied postemergence (0.035, 0.071, and 0.141 kg ai ha−1). At Yoakum, two cultivars (Tamrun OL01, Tamrun OL07) were evaluated while at Lamesa, four cultivars (FlavorRunner 458, Tamrun OL01, Tamrun OL02, and Tamrun OL07) were evaluated. In 2009, no stunting was noted at Yoakum with any herbicide regardless of cultivar. At Lamesa, FlavorRunner 458 and Tamrun OL01 were stunted at least 6% with the 0.21 kg ha−1rate of flumioxazin and 6 to 17% with the 0.07 and 0.14 kg ha−1rate of imazapic. Tamrun OL02 was stunted by all rates of flumioxazin (5%) and imazapic (5 to 18%) while Tamrun OL07 was stunted by all rates of flumioxazin (6 to 12%) and imazapic (7 to 15%) with the exception of flumioxazin at 0.05 kg ha−1. Flumioxazin did not have an effect on yield while all imazapic rates reduced yields when compared with the non-treated control. In 2010 at Yoakum, little (<2%) or no herbicide stunting was noted on any cultivar and only imazapic at 0.14 kg ha−1caused significant stunting (7%). No yield differences were noted between herbicides regardless of cultivar. At Lamesa, all cultivars were affected (6 to 9% stunting) by herbicide treatments. No peanut stunting was noted with flumioxazin at 0.05 kg ha−1while imazapic at 0.04 kg ha−1and flumioxazin at 0.11 kg ha−1resulted in 4 and 6% stunting, respectively. Flumioxazin at 0.21 kg ha−1and imazapic at 0.07 kg ha−1resulted in 12% stunting and imazapic at 0.14 kg ha−1stunted peanut 19%. Both Tamrun OL01 and Tamrun OL07 produced lower yields (≤6369 kg ha−1) than FlavorRunner 458 (7252 kg ha−1). Tamrun OL02 yields were intermediate (6889 kg ha−1). Peanut yields from herbicide treatments were not different from the non-treated control.