bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics and conceptual framework of the Easy-Play Model
Authors: Lu Chunlei , Steele Kyle
Published: March 2014

The Easy-Play Model offers a defined framework to organize games that promote an inclusive and enjoyable sport experience. The model can be implemented by participants playing sports in educational, recreational or social contexts with the goal of achieving an active lifestyle in an inclusive, cooperative and enjoyable environment. The Easy-Play Model offers a framework for modifying team sports in order to establish challenging and supportive playing opportunities in a context where competition is optimized. Arousal-seeking play theory, complexity theory and self-determination theory inform the theoretical foundations and comprehension of this model. The Easy-Play Model addresses many of the challenges that affect how frequently children and adolescents participate in physical activity through sport. This model’s alternative approach tackles physical inactivity and its health consequences by way of encouraging participation in sport. Its framework emphasizes a healthy, optimal competitiveness that appeals to all players regardless of age, skill and ability.
What did they learn in school today? A method for exploring aspects of learning in physical education
Authors: Quennerstedt Mikael , Annerstedt Claes , Barker Dean , Karlefors Inger , Larsson Håkan , Redelius Karin , Öhman Marie
Published: March 2014

This paper outlines a method for exploring learning in educational practice. The suggested method combines an explicit learning theory with robust methodological steps in order to explore aspects of learning in school physical education. The design of the study is based on sociocultural learning theory, and the approach adds to previous research within the field, both in terms of the combination of methods used and the claims made in our studies. The paper describes a way of collecting and analysing the retrieved data and discusses and illustrates the results of a study using this combination of explicit learning theory and robust methodological steps.
Motivations for game play and the social capital and civic potential of video games
Authors: Dalisay Francis , Kushin Matthew J , Yamamoto Masahiro , Liu Yung-I , Skalski Paul
Published: March 2014

This study examined the relationships between video game play motivations identified by Yee (2006), social capital (measured by social trust and neighborliness), political participation, and civic engagement. Results of a survey of 465 college students in the United States showed that the Social motivation for video game play was positively associated with neighborliness. A factor consisting of Discovery/Role-playing/Customization, subcomponents of the Immersion motivation, was positively associated with civic engagement. Also, two marginally significant associations were found: a positive one between the Achievement motivation and civic engagement, and a negative one between Escapism, a subcomponent of the Immersion motivation, and trust. Implications were discussed.
A quasi-dimensional model of turbulence and global charge motion for spark ignition engines with fully variable valvetrains
Authors: Grasreiner Sebastian , Neumann Jens , Luttermann Christoph , Wensing Michael , Hasse Christian
Published: March 2014

In this article, a new in-cylinder turbulence modeling approach aims at the improvement of quasi-dimensional simulations for modern spark ignition engines with fully variable valvetrains. Within the derived quasi-dimensional turbulence model, the turbulent production term can physically react on a change of engine operation (e.g. intake valve lift, intake valve timing, engine speed and boost pressure). Moreover, the approach offers access to detailed charge motion quantities for the first time in quasi-dimensional calculations. Hence, it is able to satisfy qualitative and quantitative turbulence descriptions within the entire operating range of the engine.
Read-alouds in preschool – A matter of discipline?
Authors: Damber Ulla
Published: March 2014

The enquiries in this study were directed towards the reading of children’s literature in preschool with the aim of describing and analysing how read-alouds were carried out in 39 preschools in the northern and southern parts of Sweden. How often were read-alouds performed? How long were they? How was literature chosen? Who initiated the read-alouds? Did dialogues and follow-up activities occur? In what context did the read-alouds take place? Student preschool teachers and preschool teachers in in-service training carried out observations over the course of one week. The results indicate that read-alouds mostly occurred once each day and that they were seldom planned or embedded in a context. Books were chosen randomly. Follow-up activities occurred on 27% of reading occasions. Thus, we conclude that read-alouds had primarily a disciplinary focus. The negative effects of these findings are discussed in relation to an ideological versus an autonomous view of literacy.
Determinants of Success in the National Football League’s Postseason
Authors: Pitts Joshua D.
Published: March 2014

This study investigates many commonly purported beliefs by fans and media concerning a team’s likelihood of advancing in the National Football League’s (NFL) postseason, including the impact of a team’s previous playoff experience on its future postseason performance. Using data covering the 1966-2012 NFL postseasons, four empirical models are estimated to examine the factors that influence various outcomes associated with a team’s postseason performance. Overall, there is little evidence to suggest that a team’s previous playoff experience has a significant impact on its future postseason performance.
Involvement of redox balance in in vitro osteoclast formation of RAW 264.7 macrophage cells in response to LPS
Authors: Odkhuu Erdenezaya , Koide Naoki , Tsolmongyn Bilegtsaikhan , Jambalganiin Ulziisaikhan , Naiki Yoshikazu , Komatsu Takayuki , Yoshida Tomoaki , Yokochi Takashi
Published: March 2014

Here we report that LPS induces osteoclast (OC) formation in murine RAW 264.7 macrophage cells in RPMI-1640 medium but not in α-minimum essential medium (α-MEM) as the original culture medium. LPS-induced OC formation in both media was examined to clarify the differential response. Receptor activator of NF-κB ligand induced OC formation in either α-MEM or RPMI-1640 medium. However, LPS-induced OC formation in RAW 264.7 cells maintained in RPMI-1640 medium, but not α-MEM, which was also supported by mouse bone marrow-derived macrophages, although they were less sensitive to LPS than RAW 264.7 cells. LPS augmented the expression of nuclear factor of activated T-cells (NFATc1) as a key transcription factor of osteoclastogenesis in cells maintained in RPMI-1640 medium, but reduced it in cells maintained in α-MEM. A high concentration of LPS was cytotoxic against cells maintained in α-MEM. Glutathione exclusively present in RPMI-1640 medium prevented LPS-induced cell death in α-MEM and augmented LPS-induced NFATc1 expression, followed by enhanced LPS-induced OC formation. LPS induced higher generation of reactive oxygen species in α-MEM than RPMI-1640 medium. An antioxidant enhanced LPS-induced OC formation, whereas a pro-oxidant reduced it. Taken together, redox balance in the culture condition was suggested to regulate in vitro LPS-induced OC formation.
Éthique de la recherche en santé mondiale : la relation Nord–Sud, quel partenariat pour quelle justice sociale ?
Authors: Godard Béatrice , Hunt Matthew , Moube Zéphirin
Published: March 2014

La recherche en santé mondiale s’inscrit dans une volonté de mobiliser des connaissances au service d’interventions et de politiques publiques pour l’atteinte équitable du bien-être commun, notamment en matière de santé. Elle joue un rôle primordial en ce sens, en favorisant l’implication des communautés et leur autonomisation et de nombreuses lignes directrices supportent un tel partenariat. Néanmoins, certains enjeux éthiques sont liés au financement de la recherche, aux environnements de recherche, à la priorisation des problématiques de recherche, aux mécanismes d’évaluation éthique posent souvent un problème de justice sociale au niveau de la redistribution des ressources et de la reconnaissance des différences culturelles. Comment alors déterminer quelle est la façon « idéale » d’agir en tenant compte de la globalité des individus et du pluralisme culturel des sociétés pour « bien faire », pour satisfaire l’exigence de l’équité? Une réflexion et une démarche éthique demeurent essentielles, ainsi qu’un dialogue entre les chercheurs du Nord et du Sud, et leurs autres partenaires que sont les décideurs, les responsables locaux et les communautés. Un tel dialogue, établi dans un continuum du développement de projets de recherche à leur pérennité, peut grandement contribuer à limiter les problèmes de justice sociale et à viser un développement plus égalitaire des savoirs scientifiques. Plusieurs chercheurs se sont déjà engagés dans cette voie, et leurs initiatives devraient être encouragées pour mettre les nouveaux savoirs au service des populations.
An Evaluation of Rules for Assigning Tables to Walk-in Parties in Restaurants
Authors: Thompson Gary M.
Published: March 2014

A survey of 276 restaurant and food-service managers found that, when it comes to seating walk-in guests, just over half maintain a policy of seating the party that has waited the longest. About one-fifth of the respondents seated the largest waiting party and the remainder used some combination of the two approaches. With that in mind, this paper uses an extensive simulation to evaluate the relative revenue outcomes for nine rules for assigning walk-in parties to tables in restaurants, taking into account such variables as restaurant size and matching party size to the table size. I test three variants of each of the “largest party” and “longest wait” rules, along with two rules that blend largest and longest. I also include the outcome of allowing guests to seat themselves. I found that one of the blended rule using party size and waiting time performed the best across all levels of all of the experimental factors, but among the simple rules, the longest wait approach was effective in most cases. Except in the largest of restaurants, allowing guests to seat themselves is the least efficient approach.
Combinatorial effects of malaria season, iron deficiency, and inflammation determine plasma hepcidin concentration in African children
Authors: Atkinson Sarah H. , Armitage Andrew E. , Khandwala Shivani , Mwangi Tabitha W. , Uyoga Sophie , Bejon Philip A. , Williams Thomas N. , Prentice Andrew M. , Drakesmith Hal
Published: March 2014

Key Points

Iron status, erythropoietic drive, inflammation, and malaria season combine to control dynamic fluctuations of hepcidin in African children. At the end of the malaria season, hepcidin is low and ID is more prevalent, so iron therapy may be beneficial at this time.
BCG-induced pneumonitis with lymphocytic pleurisy in the absence of elevated KL-6
Authors: Tobiume Makoto , Shinohara Tsutomu , Kuno Takahira , Mukai Shinji , Naruse Keishi , Hatakeyama Nobuo , Ogushi Fumitaka
Published: March 2014

Background

Pneumonitis is a rare complication of bacillus Calmette-Guerin (BCG) immunotherapy seen in patients with urothelial cancer following the repeated administration of BCG. However, no case of BCG-induced pleurisy has been reported.

Case presentation

We here report the first case of pneumonitis with lymphocytic pleurisy following bacillus Calmette-Guerin (BCG) immunotherapy. Although marked T helper cell alveolitis was found by bronchoalveolar lavage and transbronchial biopsies, no acid-fast bacillus could be identified in recovered BALF or pleural effusion. The lymphocyte stimulation test of BCG was strongly positive. However, levels of serum and bronchoalveolar lavage fluid KL-6, a useful marker for hypersensitivity pneumonitis (HP), were within normal ranges.

Conclusion

We speculate that the pathogenesis of our case may be a hypersensitive reaction to the proteic component of BCG entering the lung and pleural space, which is different from the etiology of the common type of HP.
Effects of curcuminoids identified in rhizomes of Curcuma longa on BACE-1 inhibitory and behavioral activity and lifespan of Alzheimer’s disease Drosophila models
Authors: Wang Xue , Kim Jun-Ran , Lee Seong-Baek , Kim Young-Joon , Jung Moon Young , Kwon Hyung-Wook , Ahn Young-Joon
Published: March 2014

Background

Alzheimer’s disease (AD) is the most common type of presenile and senile dementia. The human β-amyloid precursor cleavage enzyme (BACE-1) is a key enzyme responsible for amyloid plaque production, which implicates the progress and symptoms of AD. Here we assessed the anti-BACE-1 and behavioral activities of curcuminoids from rhizomes of Curcuma longa (Zingiberaceae), diarylalkyls curcumin (CCN), demethoxycurcumin (DMCCN), and bisdemethoxycurcumin (BDMCCN) against AD Drosophila melanogaster models.

Methods

Neuro-protective ability of the curcuminoids was assessed using Drosophila melanogaster model system overexpressing BACE-1 and its substrate APP in compound eyes and entire neurons. Feeding and climbing activity, lifespan, and morphostructural changes in fly eyes also were evaluated.

Results

BDMCCN has the strongest inhibitory activity toward BACE-1 with 17 μM IC50, which was 20 and 13 times lower than those of CCN and DMCCN respectively. Overexpression of APP/BACE-1 resulted in the progressive and measurable defects in morphology of eyes and locomotion. Remarkably, supplementing diet with either 1 mM BDMCCN or 1 mM CCN rescued APP/BACE1-expressing flies and kept them from developing both morphological and behavioral defects. Our results suggest that structural characteristics, such as degrees of saturation, types of carbon skeleton and functional group, and hydrophobicity appear to play a role in determining inhibitory potency of curcuminoids on BACE-1.

Conclusion

Further studies will warrant possible applications of curcuminoids as therapeutic BACE-1 blockers.
Mesenchymal cell interaction with ovarian cancer cells induces a background dependent pro-metastatic transcriptomic profile
Authors: Lis Raphael , Touboul Cyril , Halabi Najeeb M , Madduri Abishek Sainath , Querleu Denis , Mezey Jason , Malek Joel A , Suhre Karsten , Rafii Arash
Published: March 2014

Background

The cross talk between the stroma and cancer cells plays a major role in phenotypic modulation. During peritoneal carcinomatosis ovarian cancer cells interact with mesenchymal stem cells (MSC) resulting in increased metastatic ability. Understanding the transcriptomic changes underlying the phenotypic modulation will allow identification of key genes to target. However in the context of personalized medicine we must consider inter and intra tumoral heterogeneity. In this study we used a pathway-based approach to illustrate the role of cell line background in transcriptomic modification during a cross talk with MSC.

Methods

We used two ovarian cancer cell lines as a surrogate for different ovarian cancer subtypes: OVCAR3 for an epithelial and SKOV3 for a mesenchymal subtype. We co-cultured them with MSCs. Genome wide gene expression was determined after cell sorting. Ingenuity pathway analysis was used to decipher the cell specific transcriptomic changes related to different pro-metastatic traits (Adherence, migration, invasion, proliferation and chemoresistance).

Results

We demonstrate that co-culture of ovarian cancer cells in direct cellular contact with MSCs induces broad transcriptomic changes related to enhance metastatic ability. Genes related to cellular adhesion, invasion, migration, proliferation and chemoresistance were enriched under these experimental conditions. Network analysis of differentially expressed genes clearly shows a cell type specific pattern.

Conclusion

The contact with the mesenchymal niche increase metastatic initiation and expansion through cancer cells’ transcriptome modification dependent of the cellular subtype. Personalized medicine strategy might benefit from network analysis revealing the subtype specific nodes to target to disrupt acquired pro-metastatic profile.
Pegloticase immunogenicity: the relationship between efficacy and antibody development in patients treated for refractory chronic gout
Authors: Lipsky Peter E , Calabrese Leonard H , Kavanaugh Arthur , Sundy John S , Wright David , Wolfson Marsha , Becker Michael A
Published: March 2014

Introduction

The efficacy of pegloticase, a polyethylene glycol (PEG)-conjugated mammalian recombinant uricase, approved for chronic refractory gout, can be limited by the development of antibodies (Ab). Analyses from 2 replicate, 6-month, randomized controlled trials were performed to characterize Ab responses to pegloticase.

Methods

Anti-pegloticase, anti-PEG, and anti-uricase Ab were determined by validated enzyme-linked immunosorbent assays. Ab titers were analyzed for possible relationships with serum pegloticase concentrations, serum uric acid (sUA) lowering, and risk of infusion reactions (IRs).

Results

Sixty-nine (41%) of 169 patients receiving pegloticase developed high titer anti-pegloticase Ab (> 1:2430) and 40% (67/169) developed anti-PEG Ab; 1 patient receiving placebo developed high titer anti-pegloticase Ab. Only 14% (24/169) of patients developed anti-uricase Ab, usually at low titer. In responders, patients showing sustained UA lowering, mean anti-pegloticase titers at week 25 (1:837 ± 1687 with biweekly and 1:2025 ± 4506 with monthly dosing) were markedly lower than in nonresponders (1:34,528 ± 42,228 and 1:89,658 ± 297,797, respectively). Nonresponder status was associated with reduced serum pegloticase concentrations. Baseline anti-pegloticase Ab, evident in 15% (31/212) of patients, did not predict subsequent loss of urate-lowering response. Loss of sUA response preceded IRs in 44 of 56 (79%) pegloticase-treated patients.

Conclusions

Loss of responsiveness to pegloticase is associated with the development of high titer anti-pegloticase Ab that increase clearance of pegloticase and are associated with a loss of the sUA lowering effect and increased IR risk. Pre-infusion sUA can be used as a surrogate for the presence of deleterious anti-pegloticase Ab.

Trial registration

NCT00325195. Registered 10 May 2006, NCT01356498. Registered 27 October 2008.
Quantitative reconstruction of leukocyte subsets using DNA methylation
Authors: Accomando William P , Wiencke John K , Houseman E Andres , Nelson Heather H , Kelsey Karl T
Published: March 2014

Background

Cell lineage-specific DNA methylation patterns distinguish normal human leukocyte subsets and can be used to detect and quantify these subsets in peripheral blood. We have developed an approach that uses DNA methylation to simultaneously quantify multiple leukocyte subsets, enabling investigation of immune modulations in virtually any blood sample including archived samples previously precluded from such analysis. Here we assess the performance characteristics and validity of this approach.

Results

Using Illumina Infinium HumanMethylation27 and VeraCode GoldenGate Methylation Assay microarrays, we measure DNA methylation in leukocyte subsets purified from human whole blood and identify cell lineage-specific DNA methylation signatures that distinguish human T cells, B cells, NK cells, monocytes, eosinophils, basophils and neutrophils. We employ a bioinformatics-based approach to quantify these cell types in complex mixtures, including whole blood, using DNA methylation at as few as 20 CpG loci. A reconstruction experiment confirms that the approach could accurately measure the composition of mixtures of human blood leukocyte subsets. Applying the DNA methylation-based approach to quantify the cellular components of human whole blood, we verify its accuracy by direct comparison to gold standard immune quantification methods that utilize physical, optical and proteomic characteristics of the cells. We also demonstrate that the approach is not affected by storage of blood samples, even under conditions prohibiting the use of gold standard methods.

Conclusions

Cell mixture distributions within peripheral blood can be assessed accurately and reliably using DNA methylation. Thus, precise immune cell differential estimates can be reconstructed using only DNA rather than whole cells.
Memorials
Authors: Hughes Larry , Zonge Lynn , Van Reed Emmett , Carlson Norman , Lide Chet , Urquhart Scott , Wynn Jeff , Young Gary N. , Roth Jerry
Published: March 2014

Memorials for: Kenneth Zonge
Shared signaling systems in myeloid cell-mediated muscle regeneration
Authors: Tidball James G. , Dorshkind Kenneth , Wehling-Henricks Michelle
Published: March 2014

Much of the focus in muscle regeneration has been placed on the identification and delivery of stem cells to promote regenerative capacity. As those efforts have advanced, we have learned that complex features of the microenvironment in which regeneration occurs can determine success or failure. The immune system is an important contributor to that complexity and can determine the extent to which muscle regeneration succeeds. Immune cells of the myeloid lineage play major regulatory roles in tissue regeneration through two general, inductive mechanisms: instructive mechanisms that act directly on muscle cells; and permissive mechanisms that act indirectly to influence regeneration by modulating angiogenesis and fibrosis. In this article, recent discoveries that identify inductive actions of specific populations of myeloid cells on muscle regeneration are presented, with an emphasis on how processes in muscle and myeloid cells are co-regulated.
Monitoring ferumoxide-labelled neural progenitor cells and lesion evolution by magnetic resonance imaging in a model of cell transplantation in cerebral ischaemia
Authors: Panizzo Rachael A , Gadian David G , Sowden Jane C , Wells Jack A , Lythgoe Mark F , Ferretti Patrizia
Published: March 2014

Efficacy of neural stem/progenitor cell (NPC) therapies after cerebral ischaemia could be better evaluated by monitoring in vivo migration and distribution of cells post-engraftment in parallel with analysis of lesion volume and functional recovery. Magnetic resonance imaging (MRI) is ideally placed to achieve this, but still poses several challenges. We show that combining the ferumoxide MRI contrast agent Endorem with protamine sulphate (FePro) improves iron oxide uptake in cells compared to Endorem alone and is non-toxic. Hence FePro complex is a better contrast agent than Endorem for monitoring NPCs. FePro complex-labelled NPCs proliferated and differentiated normally in vitro, and upon grafting into the brain 48 hours post-ischaemia they were detected in vivo by MRI. Imaging over four weeks showed the development of a confounding endogenous hypointense contrast evolution at later timepoints within the lesioned tissue. This was at least partly due to accumulation within the lesion of macrophages and endogenous iron. Neither significant NPC migration, assessed by MRI and histologically, nor a reduction in the ischaemic lesion volume was observed in NPC-grafted brains.  Crucially, while MRI provides reliable information on engrafted cell location early after an ischaemic insult, pathophysiological changes to ischaemic lesions can interfere with cellular imaging at later timepoints.
Improving Money’s Worth Ratio Calculations: The Case of Singapore’s Pension Annuities
Authors: Fong Joelle H. , Lemaire Jean , Tse Yiu K.
Published: March 2014

This paper contributes to a better understanding of the risks involved in a life annuity investment. We study the full distribution of weighted annuity benefits and quantify risk measures such as dispersion and skewness, thereby extending the usefulness of the popular money’s worth valuation framework for life annuities. Using data from pension annuities in Singapore, we also introduce several risk measures that might appeal to less financially sophisticated retirees. A more detailed and accurate picture of the risk of investing in life annuities emerges, enabling prospective annuitants to differentiate among products that may appear seemingly uniform in terms of money’s worth, but vary widely in terms of their risk attributes.
Control of cellular motility by neuropilin-mediated physical interactions
Authors: Li Xiaobo , Parker Matthew W. , Kooi Craig W. Vander
Published: March 2014

The neuropilin (Nrp) family consists of multifunctional cell surface receptors with critical roles in a number of different cell and tissue types. A core aspect of Nrp function is in ligand-dependent cellular migration, where it controls the multistep process of cellular motility through integration of ligand binding and receptor signaling. At a molecular level, the role of Nrp in migration is intimately connected to the control of adhesive interactions and cytoskeletal reorganization. Here, we review the physiological role of Nrp in cellular adhesion and motility in the cardiovascular and nervous systems. We also discuss the emerging pathological role of Nrp in tumor cell migration and metastasis, providing motivation for continued efforts toward developing Nrp inhibitors.
Epigenetic regulations through DNA methylation and hydroxymethylation: clues for early pregnancy in decidualization
Authors: Gao Fei , Das Sanjoy K.
Published: March 2014

DNA methylation at cytosines is an important epigenetic modification that participates in gene expression regulation without changing the original DNA sequence. With the rapid progress of high-throughput sequencing techniques, whole-genome distribution of methylated cytosines and their regulatory mechanism have been revealed gradually. This has allowed the uncovering of the critical roles played by DNA methylation in the maintenance of cell pluripotency, determination of cell fate during development, and in diverse diseases. Recently, rediscovery of 5-hydroxymethylcytosine, and other types of modification on DNA, have uncovered more dynamic aspects of cell methylome regulation. The interaction of DNA methylation and other epigenetic changes remodel the chromatin structure and determine the state of gene transcription, not only permanently, but also transiently under certain stimuli. The uterus is a reproductive organ that experiences dramatic hormone stimulated changes during the estrous cycle and pregnancy, and thus provides us with a unique model for studying the dynamic regulation of epigenetic modifications. In this article, we review the current findings on the roles of genomic DNA methylation and hydroxymethylation in the regulation of gene expression, and discuss the progress of studies for these epigenetic changes in the uterus during implantation and decidualization.
Early years education, language and social background: A decade of changing policy and practice
Authors: Mroz Maria , Letts Carolyn
Published: March 2014

In recent years educationalists have been concerned that children from more socially deprived areas of the UK come to formal schooling at age five with poor language skills. In 2001 responses by early years professionals (responsible for children aged 0–5 years), to a questionnaire and follow-up interview, found that their general levels of training in language development were low. Since 2001 training has increased in the sector and there have been new initiatives around promoting language development in the early years. This paper aims to reflect on the educational context in the Early Years Foundation Stage (children aged 3–5) a decade ago; to consider how this context has changed; and, to discuss what potential impact the changes may have had on the training of Foundation Stage professionals in relation to children with speech, language and communication needs. It will draw on results from a large sample of children aged 2;0 to 7;6 years that were tested for language comprehension and production in 2010 as part of the standardisation of a redeveloped language test (New Reynell Developmental Language Scales (NRDLS): Edwards et al. 2011). There is some evidence from this study that the percentage of children from low socio-economic status (SES) backgrounds who have speech, language and communication needs (SLCN) or language delay may be decreasing.
Cryptanalysis of matrix conjugation schemes
Authors: Myasnikov Alex D. , Ushakov Alexander
Published: March 2014

In this paper we cryptanalyze two protocols: the Grigoriev–Shpilrain
authentication protocol and a public key cryptosystem due to Wang, Wang, Cao, Okamoto and Shao.
Both of these protocols use the computational hardness of some variations of the conjugacy search problem
in a class of noncommutative monoids. We devise a practical heuristic algorithm
solving those problems.
As a conclusion we claim that these protocols are insecure for the proposed parameter values.
Infinite secret sharing – Examples
Authors: Dibert Alexander , Csirmaz László
Published: March 2014

The
motivation for extending secret sharing schemes to cases when either the
set of players is infinite or the domain from which the secret and/or the
shares are drawn is infinite or both, is similar to the case when switching
to abstract probability spaces from classical combinatorial probability. It
might shed new light on old problems, could connect seemingly unrelated
problems, and unify diverse phenomena.
Definitions equivalent in the finitary case could be very much different
when switching to infinity, signifying their difference. The standard
requirement that qualified subsets should be able to determine the secret
has different interpretations in spite of the fact that, by assumption, all
participants have infinite computing power. The requirement that unqualified
subsets should have no or limited information on the secret suggests that
we also need some probability distribution. In the infinite case events with
zero probability are not necessarily impossible, and we should decide
whether bad events with zero probability are allowed or not.
In this paper, rather than giving precise definitions, we enlist an abundance
of hopefully interesting infinite secret sharing schemes. These
schemes touch quite diverse areas of mathematics such as projective
geometry, stochastic processes and Hilbert spaces. Nevertheless our main
tools are from probability theory. The examples discussed here serve as
foundation and illustration to the more theory oriented companion paper
[arXiv:1310.7423].
Using a Centrifuge to Determine Moisture Properties of Lightweight Fine Aggregate for Use in Internal Curing
Authors: Miller A. E. , Barrett T. J. , Zander A. R. , Weiss W. J.
Published: March 2014

Internally cured (IC) concrete is frequently produced using pre-wetted lightweight aggregate (LWA). One important aspect associated with preparing quality IC concrete is being able to determine the absorbed moisture and surface moisture associated with the LWA which enables aggregate moisture corrections to be made for the concrete mixture. ASTM 1761-13b specifies the use of the “paper towel method” to define a surface dry state for pre-wetted LWA; however, this can be time consuming and hard to perform at the batching plant. This paper proposes an alternative method for obtaining a surface dry state of the aggregate based on spinning the pre-wetted LWA in a centrifuge. It is shown that using a centrifuge (with bowl radius of 11.4 cm) for 3 min at 2000 rpm permits a surface dry state to be obtained consistently which enables surface and absorbed moisture to be determined accurately and rapidly. The moisture values obtained using the centrifuge correspond well with those obtained using the paper towel method.
Nanoindentation Test Integrated with Numerical Simulation to Characterize Mechanical Properties of Rock Materials
Authors: Ban Hoki , Karki Pravat , Kim Yong-Rak
Published: March 2014

It is important to determine the mechanical properties of rock materials accurately from the viewpoint of the design, analysis, and modeling of various transportation infrastructure systems. Conventional methods have some drawbacks, including relatively inaccurate measurements, cumbersome testing-analysis processes, and high variability in measurements. A nanoindentation test integrated with a numerical modeling technique has been validated in other fields as an efficient and accurate tool for the characterization of the key mechanical properties of various irregularly shaped materials, such as the rock materials in this study. This paper presents an integrated experimental-numerical effort based on the nanoindentation measurement and finite-element modeling of a representative rock material, limestone. The experimental efforts, including specimen fabrication and laboratory tests, are presented, and the corresponding analyses of test results combined with the finite-element technique and linear interpolation to evaluate the property measurements are discussed. The elastic properties estimated from the nanoindentation test are similar to the simulation results, demonstrating the validity of the test method and modeling approach. The success of the proposed approach should facilitate the better design of mixtures and structures based on the more accurate characterization of the core material properties.
Noise in Neural Populations Accounts for Errors in Working Memory
Authors: Bays Paul M.
Published: March 2014

Errors in short-term memory increase with the quantity of information stored, limiting the complexity of cognition and behavior. In visual memory, attempts to account for errors in terms of allocation of a limited pool of working memory resources have met with some success, but the biological basis for this cognitive architecture is unclear. An alternative perspective attributes recall errors to noise in tuned populations of neurons that encode stimulus features in spiking activity. I show that errors associated with decreasing signal strength in probabilistically spiking neurons reproduce the pattern of failures in human recall under increasing memory load. In particular, deviations from the normal distribution that are characteristic of working memory errors and have been attributed previously to guesses or variability in precision are shown to arise as a natural consequence of decoding populations of tuned neurons. Observers possess fine control over memory representations and prioritize accurate storage of behaviorally relevant information, at a cost to lower priority stimuli. I show that changing the input drive to neurons encoding a prioritized stimulus biases population activity in a manner that reproduces this empirical tradeoff in memory precision. In a task in which predictive cues indicate stimuli most probable for test, human observers use the cues in an optimal manner to maximize performance, within the constraints imposed by neural noise.
Prenatal Deletion of the RNA-Binding Protein HuD Disrupts Postnatal Cortical Circuit Maturation and Behavior
Authors: DeBoer Erik M. , Azevedo Ricardo , Vega Taylor A. , Brodkin Jesse , Akamatsu Wado , Okano Hideyuki , Wagner George C. , Rasin Mladen-Roko
Published: March 2014

The proper functions of cortical circuits are dependent upon both appropriate neuronal subtype specification and their maturation to receive appropriate signaling. These events establish a balanced circuit that is important for learning, memory, emotion, and complex motor behaviors. Recent research points to mRNA metabolism as a key regulator of this development and maturation process. Hu antigen D (HuD), an RNA-binding protein, has been implicated in the establishment of neuronal identity and neurite outgrowthin vitro. Therefore, we investigated the role of HuD loss of function on neuron specification and dendritogenesisin vivousing a mouse model. We found that loss of HuD early in development results in a defective early dendritic overgrowth phase and pervasive deficits in neuron specification in the lower neocortical layers and defects in dendritogenesis in the CA3 region of the hippocampus. Subsequent behavioral analysis revealed a deficit in performance of a hippocampus-dependent task: the Morris water maze. Further,HuDknock-out (KO) mice exhibited lower levels of anxiety than their wild-type counterparts and were overall less active. Last, we found thatHuDKO mice are more susceptible to auditory-induced seizures, often resulting in death. Our findings suggest that HuD is necessary for the establishment of neocortical and hippocampal circuitry and is critical for their function.
Noradrenergic β-Receptor Antagonism within the Central Nucleus of the Amygdala or Bed Nucleus of the Stria Terminalis Attenuates the Negative/Anxiogenic Effects of Cocaine
Authors: Wenzel Jennifer M. , Cotten Samuel W. , Dominguez Hiram M. , Lane Jennifer E. , Shelton Kerisa , Su Zu-In , Ettenberg Aaron
Published: March 2014

Cocaine has been shown to produce both initial rewarding and delayed anxiogenic effects. Although the neurobiology of cocaine's rewarding effects has been well studied, the mechanisms underlying its anxiogenic effects remain unclear. We used two behavioral assays to study these opposing actions of cocaine: a runway self-administration test and a modified place conditioning test. In the runway, the positive and negative effects of cocaine are reflected in the frequency of approach-avoidance conflict that animals develop about entering a goal box associated with cocaine delivery. In the place conditioning test, animals develop preferences for environments paired with the immediate/rewarding effects of cocaine, but avoid environments paired with the drug's delayed/anxiogenic actions. In the present study, these two behavioral assays were used to examine the role of norepinephrine (NE) transmission within the central nucleus of the amygdala (CeA) and the bed nucleus of the stria terminalis (BNST), each of which has been implicated in drug-withdrawal-induced anxiety and stress-induced response reinstatement. Rats experienced 15 single daily cocaine-reinforced (1.0 mg/kg, i.v.) runway trials 10 min after intracranial injection of the β1 and β2 NE receptor antagonists betaxolol and ICI 118551 or vehicle into the CeA or BNST. NE antagonism of either region dose dependently reduced approach-avoidance conflict behavior compared with that observed in vehicle-treated controls. In addition, NE antagonism selectively interfered with the expression of conditioned place aversions while leaving intact cocaine-induced place preferences. These data suggest a role for NE signaling within the BNST and the CeA in the anxiogenic actions of cocaine.
Heteromeric Kv7.2/7.3 Channels Differentially Regulate Action Potential Initiation and Conduction in Neocortical Myelinated Axons
Authors: Battefeld Arne , Tran Baouyen T. , Gavrilis Jason , Cooper Edward C. , Kole Maarten H. P.
Published: March 2014

Rapid energy-efficient signaling along vertebrate axons is achieved through intricate subcellular arrangements of voltage-gated ion channels and myelination. One recently appreciated example is the tight colocalization of Kv7 potassium channels and voltage-gated sodium (Nav) channels in the axonal initial segment and nodes of Ranvier. The local biophysical properties of these Kv7 channels and the functional impact of colocalization with Navchannels remain poorly understood. Here, we quantitatively examined Kv7 channels in myelinated axons of rat neocortical pyramidal neurons using high-resolution confocal imaging and patch-clamp recording. Kv7.2 and 7.3 immunoreactivity steeply increased within the distal two-thirds of the axon initial segment and was mirrored by the conductance density estimates, which increased from ∼12 (proximal) to 150 pS μm−2(distal). The axonal initial segment and nodal M-currents were similar in voltage dependence and kinetics, carried by Kv7.2/7.3 heterotetramers, 4% activated at the resting membrane potential and rapidly activated with single-exponential time constants (∼15 ms at 28 mV). Experiments and computational modeling showed that while somatodendritic Kv7 channels are strongly activated by the backpropagating action potential to attenuate the afterdepolarization and repetitive firing, axonal Kv7 channels are minimally recruited by the forward-propagating action potential. Instead, in nodal domains Kv7.2/7.3 channels were found to increase Navchannel availability and action potential amplitude by stabilizing the resting membrane potential. Thus, Kv7 clustering near axonal Navchannels serves specific and context-dependent roles, both restraining initiation and enhancing conduction of the action potential.
Illegally Brilliant
Authors: Hinch Jim
Published: March 2014

The author spends a day with Linda Sanchez, an undocumented student at UC Berkeley. The article follows Linda as she works at two jobs, finds time to study, and discusses how she came to the United States as a child, and her aspirations for the future.
Recuerdos
Authors: Rael Ronald , San Fratello Virginia
Published: March 2014

Ronald Rael and Virginia San Fratello have created snow globes depicting eight fanciful uses for the border wall between the United States and Mexico. They call their snow globes recuerdos, Spanish for souvenirs, a term that defines both the trinkets one might purchase at tourist shops and memories. These recuerdos are tragic, sublime, and absurd, occasionally hyperbolized, but in all cases are based on their creators’ own experiences and actual events in the liminal space that defines the boundary between the United States and Mexico.
Progesterone induces apoptosis of insulin-secreting cells: insights into the molecular mechanism
Authors: Nunes V A , Portioli-Sanches E P , Rosim M P , Araujo M S , Praxedes-Garcia P , Valle M M R , Roma L P , Hahn C , Gurgul-Convey E , Lenzen S , Azevedo-Martins A K
Published: March 2014

Progesterone has been associated with the development of gestational diabetes (GD) due to the enhancement of insulin resistance. As β-cell apoptosis participates in type 1 and type 2 diabetes pathophysiology, we proposed the hypothesis that progesterone might contribute to the development of GD through a mechanism that also involves β-cell death. To address this question, RINm5F insulin-producing cells were incubated with progesterone (25–100 μM), in the presence or absence of α-tocopherol (40 μM). After 24 or 48 h, membrane integrity and DNA fragmentation were analyzed by flow cytometry. Caspase activity was used to identify the mode of cell death. The involvement of endoplasmic reticulum stress in the action of progesterone was investigated by western blotting. Oxidative stress was measured by 2',7'-dichlorofluorescein diacetate (DCFDA) oxidation. Isolated rat islets were used in similar experiments in order to confirm the effect of progesterone in primary β-cells. Incubation of RINm5F cells with progesterone increased the number of cells with loss of membrane integrity and DNA fragmentation. Progesterone induced generation of reactive species. Pre-incubation with α-tocopherol attenuated progesterone-induced apoptosis. Western blot analyses revealed increased expression of CREB2 and CHOP in progesterone-treated cells. Progesterone caused apoptotic death of rat islet cells and enhanced generation of reactive species. Our results show that progesterone can be toxic to pancreatic β-cells through an oxidative-stress-dependent mechanism that induces apoptosis. This effect may contribute to the development of GD during pregnancy, particularly under conditions that require administration of pharmacological doses of this hormone.
A Complex Regulatory Network Coordinating Cell Cycles DuringC. elegansDevelopment Is Revealed by a Genome-Wide RNAi Screen
Authors: Roy Sarah H , Tobin David V , Memar Nadin , Beltz Eleanor , Holmen Jenna , Clayton Joseph E , Chiu Daniel J , Young Laura D , Green Travis H , Lubin Isabella , Liu Yuying , Conradt Barbara , Saito R Mako
Published: March 2014

The development and homeostasis of multicellular animals requires precise coordination of cell division and differentiation. We performed a genome-wide RNA interference screen in Caenorhabditis elegans to reveal the components of a regulatory network that promotes developmentally programmed cell-cycle quiescence. The 107 identified genes are predicted to constitute regulatory networks that are conserved among higher animals because almost half of the genes are represented by clear human orthologs. Using a series of mutant backgrounds to assess their genetic activities, the RNA interference clones displaying similar properties were clustered to establish potential regulatory relationships within the network. This approach uncovered four distinct genetic pathways controlling cell-cycle entry during intestinal organogenesis. The enhanced phenotypes observed for animals carrying compound mutations attest to the collaboration between distinct mechanisms to ensure strict developmental regulation of cell cycles. Moreover, we characterized ubc-25, a gene encoding an E2 ubiquitin-conjugating enzyme whose human ortholog, UBE2Q2, is deregulated in several cancers. Our genetic analyses suggested that ubc-25 acts in a linear pathway with cul-1/Cul1, in parallel to pathways employing cki-1/p27 and lin-35/pRb to promote cell-cycle quiescence. Further investigation of the potential regulatory mechanism demonstrated that ubc-25 activity negatively regulates CYE-1/cyclin E protein abundance in vivo. Together, our results show that the ubc-25-mediated pathway acts within a complex network that integrates the actions of multiple molecular mechanisms to control cell cycles during development.
Revisiting the nexus between financial development, FDI, and growth: New evidence from second generation econometric procedures in the Turkish context
Authors: Güngör Hasan , Katircioglu Salih , Mercan Mehmet
Published: March 2014

This study investigates the impact of the selected financial development proxies and foreign direct investment (FDI) on the growth in the case of Turkey, using annual data for the 1960–2011 period. The second-generation econometric procedure has been applied for the first time to the Turkish data with this respect. Unit root tests by Carrion-i-Silvestre et al. (2009) assume that real income, financial development proxies, and FDI are non-stationary at levels, but become stationary at first differences through multiple structural breaks. Cointegration results by Maki (2012) confirm the existence of a long-term equilibrium relationship between real income growth, financial development, and FDI, again through multiple structural breaks. Finally, this paper confirms that financial development and FDI are long-term drivers of real income, which enable it to react to its long-term path significantly.
The price of gold and the exchange rate: Evidence from threshold cointegration and threshold granger causality analyses for Turkey
Authors: Gürış Burak , Kiran Burcu
Published: March 2014

This paper explores the relationship between gold prices and the US dollar/Turkish lira exchange rate between 1990–2011 by using cointegration and Granger causality analyses. The empirical findings indicate that there is a threshold cointegration relationship between the two variables. The threshold value obtained from the estimation of threshold vector error correction model equals −3.268. The Granger test indicates that there is evidence of a bi-directional causal relationship between gold prices and the exchange rate, except when the threshold parameter exceeds the threshold value in the exchange rate equation. According to these findings, gold price can be used as a hedge against the exchange rate. However, since this relationship disappears above the threshold value, gold is only a weak hedge against exchange rate fluctuations.