bluuebunny/crossref_metadata_2025 huggingface dataset:
Licensing Foreign Technology and the Moderating Role of Local R&D Collaboration: Extending the Relational View
Authors: Wang Yuandi , Li‐Ying Jason
Published: October 2014

The relational resource‐based view posits that performance differences among firms can be explained not only by the possession of internal resources but also by maintaining and developing relationships with external partners. However, studies in the extant literature usually address the separated roles of various external relationships of focal firms, but the literature has not addressed how relationships with different sets of knowledge partners are related to each other and influence focal firms' performance. Therefore, to fill this research gap, this study focuses on how technological resources acquired from one set of partners (licensing foreign technologies) may generate subsequent internal and relational rents in terms of technological innovation in the context of collaboration with an entirely different set of knowledge partners (local R&D partners). Specifically, we propose that local R&D collaborations need to be large in scale and broad in scope. The empirics are based on the analysis of a sample of 160 high‐tech Chinese firms observed from 2000 to 2011. Consistent with our predictions, our findings contribute to extending the relational view by addressing the relations among the relationships of focal firms.
Transnational Disorders: Returned Migrants at Oaxaca's Psychiatric Hospital
Authors: Duncan Whitney L.
Published: October 2014

This article examines experiences of returned migrants seeking mental health care at the public psychiatric hospital in Oaxaca, Mexico. Approximately one‐third of the hospital's patients have migration experience, and many return to Oaxaca due to mental health crises precipitated by conditions of structural vulnerability and “illegality” in the United States. Once home, migrants, their families, and their doctors struggle to interpret and allay these “transnational disorders”—disorders structurally produced and personally experienced within the borders of more than one country. Considering how space and time shape illness and treatment among transnational migrants, I contend that a critical phenomenology of illegality must incorporate migrant experience and political economy on both sides of the border before, during, and after migration.
Natural selection in a postglacial range expansion: the case of the colour cline in the European barn owl
Authors: Antoniazza Sylvain , Kanitz Ricardo , Neuenschwander Samuel , Burri Reto , Gaigher Arnaud , Roulin Alexandre , Goudet Jérôme
Published: October 2014

Gradients of variation—or clines—have always intrigued biologists. Classically, they have been interpreted as the outcomes of antagonistic interactions between selection and gene flow. Alternatively, clines may also establish neutrally with isolation by distance (IBD) or secondary contact between previously isolated populations. The relative importance of natural selection and these two neutral processes in the establishment of clinal variation can be tested by comparing genetic differentiation at neutral genetic markers and at the studied trait. A third neutral process, surfing of a newly arisen mutation during the colonization of a new habitat, is more difficult to test. Here, we designed a spatially explicit approximate Bayesian computation (ABC) simulation framework to evaluate whether the strong cline in the genetically based reddish coloration observed in the European barn owl (Tyto alba) arose as a by‐product of a range expansion or whether selection has to be invoked to explain this colour cline, for which we have previously ruled out the actions of IBD or secondary contact. Using ABC simulations and genetic data on 390 individuals from 20 locations genotyped at 22 microsatellites loci, we first determined how barn owls colonized Europe after the last glaciation. Using these results in new simulations on the evolution of the colour phenotype, and assuming various genetic architectures for the colour trait, we demonstrate that the observed colour cline cannot be due to the surfing of a neutral mutation. Taking advantage of spatially explicit ABC, which proved to be a powerful method to disentangle the respective roles of selection and drift in range expansions, we conclude that the formation of the colour cline observed in the barn owl must be due to natural selection.
Subject‐Involving Luck
Authors: Milburn Joe
Published: October 2014

In recent years, philosophers have tended to think of luck as being a relation between an event (taken in the broadest sense of the term) and a subject; to give an account of luck is to fill in the right‐hand side of the following biconditional: an event e is lucky for a subject S if and only if ____. We can call such accounts of luck subject‐relative accounts of luck, since they attempt to spell out what it is for an event to be lucky relative to a subject. This essay argues that we should understand subject‐relative luck as a secondary phenomenon. What is of philosophical interest is giving an account of subject‐involving luck, i.e., filling in the right‐hand side of this biconditional: it is a matter of luck that S ϕs iff ____. The essay argues that one of the upshots of focusing on subject‐involving luck is that lack of control accounts of luck (LCALs) become more attractive. In particular, a range of counterexamples to LCALs of subject‐relative luck do not apply to LCALs of subject‐involving luck.
Luck, Knowledge, and “Mere” Coincidence
Authors: Riggs Wayne D.
Published: October 2014

There are good reasons for pursuing a theory of knowledge by way of understanding the connection between knowledge and luck. Not surprisingly, then, there has been a burgeoning of interest in “luck theories” of knowledge as well as in theories of luck in general. Unfortunately, “luck” proves to be as recalcitrant an analysandum as “knows.” While it is well worth pursuing a general theory of luck despite these difficulties, our theory of knowledge might be made more manageable if we could find a more restricted notion that captured the core phenomena of luck that are relevant to whether or not someone knows. This essay makes the attempt to delineate such a notion, called “mere coincidence.”
The Unbearable Uncertainty Paradox
Authors: Roeser Sabine
Published: October 2014

People can be risk seeking and risk averse, but people can also be uncertainty averse: in other words, if risk is at least the possibility of an unwanted affect, then it is not only the unwanted effect that they want to avoid, it can also be the uncertainty inherent in the possibility that they wish to avoid. This uncertainty aversion can even lead to a state where someone prefers a certain outcome at all costs, even when it is the worst case. This gives rise to the following paradox: the worst case seems to be more acceptable than the state where there is still a chance that it will not materialize. We can call this the Unbearable Uncertainty Paradox. This essay provides a first conceptual sketch of this phenomenon that seems to be widespread but nevertheless does not appear to have been identified before, either by philosophers or by psychologists.
Exogenous H2S enhances mice gastric smooth muscle tension through S‐sulfhydration of KV4.3, mediating the inhibition of the voltage‐dependent potassium current
Authors: Liu D.‐H. , Huang X. , Meng X.‐M. , Zhang C.‐M. , Lu H.‐L. , Kim Y.‐C. , Xu W.‐X.
Published: October 2014

Background

Hydrogen sulfide (H2S) has been shown to have an excitatory effect on gastric motility, but the underlying molecular mechanism is unclear. In this study, we aimed to investigate the possible targets of H2S and determine how H2S affects its target proteins during H2S‐induced contraction.

Methods

Patch‐clamp and potentiometric fluorescence dye were utilized to measure the electrophysiological changes. The Biotin‐switch assay was utilized to detect the protein S‐sulfhydration. The isometric tension measurement was conducted too.

Key Results

Exogenous H2S enhanced the tonic contraction of gastric antral smooth muscle, and voltage‐dependent potassium channel (KV) blocker and Dithiothreitol (DTT, a reducing agent) abolished the excitatory effect of NaHS. Exogenous H2S inhibited the fast inactivation component of the voltage‐dependent potassium channel current (IKVfast) in isolated gastric antral smooth muscle cells. H2S inhibited the KV4.3 current in H293 cells with heterologous expression of KV4.3, but did not inhibit the KV4.1 and KV4.2 currents, which together contribute greatly to IKVfast. NaHS significantly decreased the membrane potential in cultured gastric smooth muscle cells, but the NaHS‐induced depolarization was suppressed by knockdown of KV4.3 and N‐ethylamaleimide (NEM), a free thiol group blocker. In addition, NaHS sulfhydrated KV4.3 in H293 cells and in gastric smooth muscle tissue. However, this S‐sulfhydration was inhibited by NEM and DTT. Meanwhile the NaHS‐induced inhibition of IKVfast and KV4.3 was also blocked by NEM and DTT.

Conclusions & Inferences

These results suggest that exogenous H2S sulfhydrates KV4.3 to decrease the membrane potential, thereby enhancing the basal tension of gastric antral smooth muscle.
Is ‘peak N’ key to understanding the timing of flowering in annual plants?
Authors: Guilbaud Camille S. E. , Dalchau Neil , Purves Drew W. , Turnbull Lindsay A.
Published: October 2014

Flowering time in annual plants has large fitness consequences and has been the focus of theoretical and empirical study. Previous theory has concluded that flowering time has evolved over evolutionary time to maximize fitness over a particular season length.

We introduce a new model where flowering is cued by a growth‐rate rule (peak nitrogen (N)). Flowering is therefore sensitive to physiological parameters and to current environmental conditions, including N availability and the presence of competitors.

The model predicts that, when overall conditions are suitable for flowering, plants should never flower after ‘peak N’, the point during development when the whole‐plant N uptake rate reaches its maximum. Our model further predicts correlations between flowering time and vegetative growth rates, and that the response to increased N depends heavily on how this extra N is made available. We compare our predictions to observations in the literature.

We suggest that annual plants may have evolved to use growth‐rate rules as part of the cue for flowering, allowing them to smoothly and optimally adjust their flowering time to a wide range of local conditions. If so, there are widespread implications for the study of the molecular biology behind flowering pathways.
Imagining World War III—In 2034
Authors: LUKIN ARTYOM
Published: October 2014

In 1990, right after the Berlin Wall fell, NPQ published our Spring edition, titled “The New World Disorder,” about the nationalistic chaos and up‐in‐theair sensibility of that fraught new historical moment.

Nearly a quarter of a century later, the regime of globalization that had supplanted the Cold War world of blocs is itself coming apart at the seams. Even Henry Kissinger these days says “the world order is crumbling.”

Will this New World Disorder 2.0 revert to a system of conflicting blocs, as during the Cold War, or will we be mature enough to save the interdependence of plural identities that is the foundation of a new global civilization?

In this section our contributors offer their perspectives on what the future holds.
Sugar demand of ripening grape berries leads to recycling of surplus phloem water via the xylem
Authors: KELLER MARKUS , ZHANG YUN , SHRESTHA PRADEEP M. , BIONDI MARCO , BONDADA BHASKAR R.
Published: October 2014

We tested the common assumption that fleshy fruits become dependent on phloem water supply because xylem inflow declines at the onset of ripening. Using two distinct grape genotypes exposed to drought stress, we found that a sink‐driven rise in phloem inflow at the beginning of ripening was sufficient to reverse drought‐induced berry shrinkage. Rewatering accelerated berry growth and sugar accumulation concurrently with leaf photosynthetic recovery. Interrupting phloem flow through the peduncle prevented the increase in berry growth after rewatering, but interrupting xylem flow did not. Nevertheless, xylem flow in ripening berries, but not berry size, remained responsive to root or shoot pressurization. A mass balance analysis on ripening berries sampled in the field suggested that phloem water inflow may exceed growth and transpiration water demands. Collecting apoplastic sap from ripening berries showed that osmotic pressure increased at distinct rates in berry vacuoles and apoplast. Our results indicate that the decrease in xylem inflow at the onset of ripening may be a consequence of the sink‐driven increase in phloem inflow. We propose a conceptual model in which surplus phloem water bypasses the fruit cells and partly evaporates from the berry surface and partly moves apoplastically to the xylem for outflow.
The Legitimacy of U.S. Government Agency Power
Authors: Feldman Daniel L.
Published: October 2014

A synthesis of the work of two political and legal scholars, John Rohr and Lon Fuller, properly balances constitutional and managerial values, supplementing other theories that offer useful but insufficient support for American government agency legitimacy. Agencies reflecting that balance would strengthen their legitimacy—a particularly valuable goal in an era of low confidence in American government. Rohr's focus on the constitutional oath of office and American regime values, and Fuller's insistence that law must serve human needs, leave a great deal indeterminate and discretionary but nevertheless set boundaries. Bureaucrats who risked or sacrificed their jobs to avoid transgressing those boundaries offer models of loyalty to the Rohr‐Fuller balance of values. The behavior of officials in the Office of the Comptroller of the Currency in thwarting measures that could have averted the financial crisis of 2007 offers a model of bureaucrats who violated those boundaries.
Financial Constraints and the Extensive and Intensive Margin of Firm Exports: Panel Data Evidence from China
Authors: Egger Peter H. , Kesina Michaela
Published: October 2014

Some theoretical work suggests credit constraints to hamper exports while other work suggests that they deter firms' sales at large. Hence, credit constraints might reduce the export–sales ratio or not. This paper assesses the role of credit constraints for the export–sales ratio at the firm level. We explore this hypothesis empirically, using cross‐section and panel data on Chinese enterprises compiled by the National Bureau of Statistics of China. We approximate credit constraints by a firm's ratio of liquid debt to sales and, alternatively, the ratio of liquid assets to total assets. In particular, we estimate the impact of these financial fundamentals on the extensive and the intensive margins of firm‐level exports in two‐part fractional response models. Fixed effects panel regressions point to a negative relationship between export–sales ratios and credit constraints only at the extensive margin.
Multinational Enterprises, Absorptive Capacity and Export Spillovers: Evidence from Polish Firm‐level Data
Authors: Cieślik Andrzej , Hagemejer Jan
Published: October 2014

An important benefit attributed to the activity of multinational enterprises (MNEs) in developing and transition countries is its effect on international market access. Through a variety of channels the presence of MNEs is expected to reduce the costs faced by indigenous firms in breaking into international markets and in turn boost their export prospects. In this paper we use an extensive Polish firm‐level dataset for the period 2000–2008 to verify whether MNEs have positively contributed to the export performance of indigenous firms. We track not only sectoral and geographical spillovers stemming from the activity of MNEs but also control for firm‐specific characteristics that affect indigenous firms' decisions to export including their absorptive capacity. Our empirical results support the existence of positive spillovers (related to MNE export activity) at the sectoral level but not at the regional level. Finally, we find that individual absorptive capacity determines the size of export spillovers.
The Death of German Firms: What Role for Foreign Direct Investment?
Authors: Franco Chiara , Weche Gelübcke John P.
Published: October 2014

This paper aims at examining the role played by inward foreign direct investment (FDI) in affecting the exit probabilities of German manufacturing firms in the pre‐crisis year 2008. We introduce two main novelties: in the first place, we include the FDI variable, dividing it between types of foreign investor (industrial versus financial) besides the analysis with the division by country of origin. Second, we analyse whether FDIs may have effects not only on the probability that a firm exits from the domestic market, but also on whether it stops being internationally involved, that is, whether it stops importing or exporting. We find that German firms, in most cases, suffer from higher competition introduced by foreign firms except when they are part of a high‐R&D region or a high‐tech sector, because they have enough absorptive capacity to take advantage of possible spillover effects. We also find that US FDIs have a crowding out effect for firms located in low‐tech sectors but not in high‐tech sectors. The results are reversed when considering financial investments instead of industrial investments. Finally, we find that FDIs are negatively correlated with exits from export markets but positively with those from import markets.
Experimental study of the oscillation of spheres in an acoustic levitator
Authors: Andrade Marco A. B. , Pérez Nicolás , Adamowski Julio C.
Published: October 2014

The spontaneous oscillation of solid spheres in a single-axis acoustic levitator is experimentally investigated by using a high speed camera to record the position of the levitated sphere as a function of time. The oscillations in the axial and radial directions are systematically studied by changing the sphere density and the acoustic pressure amplitude. In order to interpret the experimental results, a simple model based on a spring-mass system is applied in the analysis of the sphere oscillatory behavior. This model requires the knowledge of the acoustic pressure distribution, which was obtained numerically by using a linear finite element method (FEM). Additionally, the linear acoustic pressure distribution obtained by FEM was compared with that measured with a laser Doppler vibrometer. The comparison between numerical and experimental pressure distributions shows good agreement for low values of pressure amplitude. When the pressure amplitude is increased, the acoustic pressure distribution becomes nonlinear, producing harmonics of the fundamental frequency. The experimental results of the spheres oscillations for low pressure amplitudes are consistent with the results predicted by the simple model based on a spring-mass system.
Stationary noise responses in a nonlinear model of cochlear mechanics: Iterative solutions in the frequency domain
Authors: Liu Yi-Wen
Published: October 2014

To examine quasilinear filtering properties in cochlear mechanics, Liu and Neely [(2012). What Fire is in Mine Ears: Progress in Auditory Biomechanics, edited by C. A. Shera and E. S. Olson (AIP, Melville, NY), pp. 218–223] calculated Wiener kernels of a nonlinear cochlear model; it was verified that the model's responses to noise could be accurately predicted by treating the kernels as the impulse responses of an equivalent linear system. However, this previous work fell short of showing that the quasilinear filters could be realized under the same structure of the model, a property predicted by de Boer [(1997). Aud. Neurosci. 3, 377–388]. To address the issue of realizability, this paper presents a method that computes the cochlear model's responses to noise iteratively in the frequency domain. First, cochlear transfer functions are calculated as if the system is linear; then, the efficiency of the outer hair cell electromechanical transduction is adjusted. The two steps repeat until the transfer functions converge. Simulation shows that, as the stimulus level increases, the magnitude response of the cochlea decreases and the latency shortens. The corresponding impulse responses are approximately equal to the Wiener kernels obtained in time-domain simulation; as the stimulus varies, the approximation error is <5% in terms of energy. Thus, the Wiener kernels are effectively computed via the present method, which guarantees that the structure of the model is preserved.
Study of the effects of vocal tract constriction on glottal vibration
Authors: Mittal Vinay Kumar , Yegnanarayana B. , Bhaskararao Peri
Published: October 2014

Characteristics of glottal vibration are affected by the obstruction to the flow of air through the vocal tract system. The obstruction to the airflow is determined by the nature, location, and extent of constriction in the vocal tract during production of voiced sounds. The effects of constriction on glottal vibration are examined for six different categories of speech sounds having varying degree of constriction. The effects are examined in terms of source and system features derived from the speech and electroglottograph signals. It is observed that a high degree of constriction causing obstruction to the flow of air results in large changes in these features, relative to the adjacent steady vowel regions, as in the case of apical trill and alveolar fricative sounds. These changes are insignificant when the obstruction to the airflow is less, as in the case of velar fricative and lateral approximant sounds. There are no changes in the excitation features when there is a free flow of air along the auxiliary tract, despite constriction in the vocal tract, as in the case of nasals. These studies show that effects of constriction can indeed be observed in the features of glottal vibration as well as vocal tract resonances.
The edge wave on an elastically supported Kirchhoff plate
Authors: Kaplunov Julius , Prikazchikov Danila A. , Rogerson Graham A. , Lashab Mohamed I.
Published: October 2014

This Letter deals with an analysis of bending edge waves propagating along the free edge of a Kirchhoff plate supported by a Winkler foundation. The presence of a foundation leads to a non-zero cut-off frequency for this wave, along with a local minimum of the associated phase velocity. This minimum phase velocity corresponds to a critical speed of an edge moving load and is analogous to that in the classical 1D moving load problem for an elastically supported beam.
Acoustic tracking of migrating salmon
Authors: Kupilik Matthew J. , Petersen Todd
Published: October 2014

Annual salmon migrations vary significantly in annual return numbers from year to year. In order to determine when a species' sustainable return size has been met, a method for counting and sizing the spawning animals is required. This project implements a probability hypothesis density tracker on data from a dual frequency identification sonar to automate the process of counting and sizing the fish crossing an insonified area. Data processing on the sonar data creates intensity images from which possible fish locations can be extracted using image processing. These locations become the input to the tracker. The probability hypothesis density tracker then solves the multiple target tracking problem and creates fish tracks from which length information is calculated using image segmentation. The algorithm is tested on data from the 2010 salmon run on the Kenai river in Alaska and compares favorably with statistical models from sub-sampling and manual measurements.
Modeling environmental noise exceedances using non-homogeneous Poisson processes
Authors: Guarnaccia Claudio , Quartieri Joseph , Barrios Juan M. , Rodrigues Eliane R.
Published: October 2014

In this work a non-homogeneous Poisson model is considered to study noise exposure. The Poisson process, counting the number of times that a sound level surpasses a threshold, is used to estimate the probability that a population is exposed to high levels of noise a certain number of times in a given time interval. The rate function of the Poisson process is assumed to be of a Weibull type. The presented model is applied to community noise data from Messina, Sicily (Italy). Four sets of data are used to estimate the parameters involved in the model. After the estimation and tuning are made, a way of estimating the probability that an environmental noise threshold is exceeded a certain number of times in a given time interval is presented. This estimation can be very useful in the study of noise exposure of a population and also to predict, given the current behavior of the data, the probability of occurrence of high levels of noise in the near future. One of the most important features of the model is that it implicitly takes into account different noise sources, which need to be treated separately when using usual models.
Shedding Light on the Genome’s Dark Matter
Authors: Mefford Heather C.
Published: October 2014

Recurrent mutations in noncoding DNA have been found in human tumors.
Gynoecial ontogeny of Anthurium: contributions for floral developmental studies in Araceae (Alismatales)
Authors: Poli Letícia Peres , Temponi Lívia Godinho , Coan Alessandra Ike
Published: October 2014

Studies on floral development have widened the knowledge on the floral morphology of Araceae, particularly in genera delimited through classical taxonomic treatments. In Pothoideae, floral ontogenetic studies are limited to some representatives of Pothoidium Schott and Pothos L. and only one species of Anthurium Schott, with no focus on gynoecium. This background reveals a lack of ontogenetic data on the largest genus in the clade. This paper presents gynoecial ontogeny of species circumscribed in different sections of Anthurium, describes gynoecial developmental patterns, and evaluates the relevance of ontogenetic characteristics in the taxonomy of the sections studied. New data for the Araceae include the recognition of four floral developmental phases, the carpellary nature of the ovarian septum, and the development of the symplicate and synascidiate zones of the gynoecium. The apical septum described in Anthurium scandens (Aubl.) Engl. is first reported for the genus in this study. We also highlight the importance of these ontogenetic data as new information for the Pothoideae within Araceae and to understand the notable phases of floral development in the reproductive biology of Anthurium.
The diversity and antimicrobial activity of endophytic fungi associated with medicinal plant Baccharis trimera (Asteraceae) from the Brazilian savannah
Authors: Vieira Mariana L.A. , Johann Susana , Hughes Frederic M. , Rosa Carlos A. , Rosa Luiz H.
Published: October 2014

The fungal endophyte community associated with Baccharis trimera, a Brazilian medicinal plant, was characterized and screened for its ability to present antimicrobial activity. By using molecular methods, we identified and classified the endophytic fungi obtained into 25 different taxa from the phyla Ascomycota and Basidiomycota. The most abundant species were closely related to Diaporthe phaseolorum, Pestalotiopsis sp. 1, and Preussia pseudominima. The differences observed in endophytic assemblages from different B. trimera specimens might be associated with their crude extract activities. Plants that had higher α-biodiversity were also those that contributed more to the regional (γ) diversity. All fungal isolates were cultured and their crude extracts screened to examine the antimicrobial activities. Twenty-three extracts (12.8%) displayed antimicrobial activities against at least one target microorganism. Among these extracts, those obtained from Epicoccum sp., Pestalotiopsis sp. 1, Cochliobolus lunatus, and Nigrospora sp. presented the best minimum inhibitory concentration values. Our results show that the endophytic fungal community associated with the medicinal plant B. trimera included few dominant bioactive taxa, which may represent sources of compounds with antifungal activity. Additionally, the discovery of these bioactive fungi in association with B. trimera suggests that Brazilian plants used as folk medicine may shelter a rich fungal diversity as well as taxa able to produce bioactive metabolites with antimicrobial activities.
MEASURING TRADE COSTS FROM RELATIVE PRICES: THE ROLE OF LOCATION AND GOODS CHARACTERISTICS
Authors: HUH IN , LEE INKOO
Published: October 2014

This paper estimates the trade costs from international relative prices, and studies the economic determinants of implied trade costs. We find that the magnitude of trade costs depends on the characteristics of both the type of good and set of locations under examination. In particular, it is found that higher non-traded input share and trade barriers, and lower tradability of goods lead to a larger trade cost, as does a lower proximity of geographic distance between locations.
Possible effects of the large extra dimensions on ZZW production at the LHC
Authors: Chen Chong , Guo Lei , Ma Wen-Gan , Zhang Ren-You , Li Xiao-Zhou , Zhang Yu
Published: October 2014

We investigate the possible large extra dimensions (LED) effects induced by the Kaluza–Klein (KK) gravitons up to the QCD next-to-leading order (NLO) on ZZW production at the large hadron collider (LHC). The integrated cross-sections and some kinematic distributions are presented in both the Standard Model (SM) and the LED model. The numerical results demonstrate that the NLO QCD corrections are sizeable and remarkably reduce the leading order (LO) LED effect depending strongly on the phase space. The NLO LED relative discrepancies of the total cross-section could become sizable for the ZZW production, if we apply proper event selection criteria. We find that the LO result overestimates the LED effect and is insufficient to provide a believable theoretical prediction.
The dispersion relation for matter waves in a two-phase vacuum
Authors: Wesson Paul S.
Published: October 2014

The cosmological constant Λ of general relativity is a natural consequence of embedding Einstein's theory in a five-dimensional (5D) theory of the type needed for unification. The exact 5D solution for Λ<0 shows waves in ordinary three-dimensional (3D) space with properties similar to those of de Broglie or matter waves. Here the dispersion relation is derived for matter waves in a toy two-phase model, where regions with Λ<0 and Λ>0 average on the large scale to Λ≃0, thus providing in principle a resolution of the cosmological-constant problem. A striking result of the analysis is that the dispersion relation is bimodal, with a well-defined window of high-frequency transmission which effectively defines the speed of light.
Lamb wave band gaps in one-dimensional radial phononic crystal slabs
Authors: Li Yinggang , Chen Tianning , Wang Xiaopeng
Published: October 2014

In this paper, we theoretically investigate the band structures of Lamb wave in one-dimensional radial phononic crystal (PC) slabs composed of a series of alternating strips of epoxy and aluminum. The dispersion relations, the power transmission spectra and the displacement fields of the eigenmodes are calculated by using the finite element method based on two-dimensional axial symmetry models in cylindrical coordinates. The axial symmetry model is validated by three-dimensional finite element model in Cartesian coordinates. Numerical results show that the proposed radial PC slabs can yield several complete band gaps with a variable bandwidth exist for elastic waves. Furthermore, the effects of the filling fraction and the slab thickness on the band gaps are further explored numerically. It is worth observing that, with the increase of the filling fraction, both the lower and upper edges of the band gaps are simultaneously shifted to higher frequency, which results from the enhancement interaction between the rigid resonance of the scatterer and the matrix. The slab thickness is the key parameter for the existence and the width of complete band gaps in the radial PC slabs. These properties of Lamb waves in the radial PC plates can potentially be applied to optimize band gaps, generate filters and design acoustic devices in the rotary machines and structures.
Some Intuitionist Fuzzy Weighted Geometric Distance Measures and Their Application to Group Decision Making
Authors: Peng Bo , Ye Chunming , Zeng Shouzhen
Published: October 2014

The ordered weighted distance (OWD) measure developed by Xu and Chen having been proved suitable to deal with the situation where the input arguments are represented in exact numerical values. In this paper, we develop some new geometric distance measures with intuitionistic fuzzy information, which are the generalization of some widely used distance measures, including the intuitionistic fuzzy weighted geometric distance (IFWGD) measure, the intuitionistic fuzzy ordered weighted geometric distance (IFOWGD) measure, the intuitionistic fuzzy ordered weighted geometric Hamming distance (IFOWGHD) measure, the intuitionistic fuzzy ordered weighted geometric Euclidean distance (IFOWGED) measure, the intuitionistic fuzzy hybrid weighted geometric distance (IFHWGD) measure. These developed weighted geometric distance measures are very suitable to deal with the situation where the input arguments are represented in intuitionistic fuzzy values. And then, we present a consensus reaching process based on the developed distance measures with intuitionistic fuzzy preference information for group decision making. Finally, we apply the developed approach with a numerical example to group decision making under intuitionistic fuzzy environment.
An Archimedean Copula Family with Hyperbolic Cotangent Generator
Authors: Najjari Vadoud , Bacigál Tomáš , Bal Hasan
Published: October 2014

Hyperbolic cotangent function is proposed as a generator of new Archimedean copula family and several properties are revealed. To show performance in real data analysis, application to modeling dependence between monthly temperature extremes as well as between flood peak and volume is given.
CHARACTERIZATION AND MICROHARDNESS OF ELECTRODEPOSITED Ni–W COATINGS OBTAINED FROM GLUCONATE BATH
Authors: BERA PARTHASARATHI , KUMAR M. DINESH , ANANDAN CHINNASAMY , SHIVAKUMARA C.
Published: October 2014

Ni – W alloy coatings are electrodeposited with direct and pulse current using gluconate bath at pH5. Effects of direct current (DC) and pulse current (PC) on structural characteristics of the coatings have been investigated by energy dispersive X-ray spectroscopy (EDXS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). EDXS shows that W contents are 13.3 and 12.6 at.% in DC and PC (10:40) Ni – W coatings, respectively. FESEM analysis exhibits the homogeneous coarse nodular morphology in DC plated deposits. DSC studies reveal that Ni – W coatings are thermally stable up to 400°C. XPS studies demonstrate that DC plated coating has significant amount of Ni and W in elemental form along with their respective oxidized species. In contrast, mainly oxidized metals are present in the as-deposited coatings prepared with PC plating. The microhardness of pulse current (100:400) deposited Ni – W coating is about 750 HK that is much higher than DC plated coating (635 HK). Heat treatment of the deposits carried out at different temperatures show a significant increase in microhardness which can be comparable with hard chromium coatings.
Density functional theoretical study on the reaction mechanism ofSiHFradical with HNCO
Authors: Hou Li-Jie , Wu Bo-Wan , Han Yan-Xia , Kong Chao , Chen Dong-Ping , Gao Li-Guo
Published: October 2014

The reaction mechanism of SiHF radical with HNCO has been investigated by the B3LYP method of density functional theory (DFT), while the geometries and harmonic vibration frequencies of reactants, intermediates, transition states and products have been calculated at the B3LYP/6-311++G** level. To obtain more precise energy result, stationary point energies were calculated at the CCSD(T)/6-311++G**//B3LYP/6-311++G** level. In temperature range of 100 K to 1900 K, the statistical thermodynamics and Eyring transition state theory with Winger correction are used to study the thermodynamic and kinetic characters of the channel with low energy barrier at 1.0 Atm. SiHF + HNCO → IM 8 → TS 8 → SiFNHCHO ( P 3) was the main channel with low potential energy in the singlet state, SiFNHCHO was the main product. The analyses for the combining interaction between SiHF radical and HNCO with the atom-in-molecules (AIM) theory have been performed. There are three reaction channels in the triplet.
PIERO ontology for analysis of biochemical transformations: Effective implementation of reaction information in the IUBMB enzyme list
Authors: Kotera Masaaki , Nishimura Yosuke , Nakagawa Zen-Ichi , Muto Ai , Moriya Yuki , Okamoto Shinobu , Kawashima Shuichi , Katayama Toshiaki , Tokimatsu Toshiaki , Kanehisa Minoru , Goto Susumu
Published: October 2014

Genomics is faced with the issue of many partially annotated putative enzyme-encoding genes for which activities have not yet been verified, while metabolomics is faced with the issue of many putative enzyme reactions for which full equations have not been verified. Knowledge of enzymes has been collected by IUBMB, and has been made public as the Enzyme List. To date, however, the terminology of the Enzyme List has not been assessed comprehensively by bioinformatics studies. Instead, most of the bioinformatics studies simply use the identifiers of the enzymes, i.e. the Enzyme Commission (EC) numbers. We investigated the actual usage of terminology throughout the Enzyme List, and demonstrated that the partial characteristics of reactions cannot be retrieved by simply using EC numbers. Thus, we developed a novel ontology, named PIERO, for annotating biochemical transformations as follows. First, the terminology describing enzymatic reactions was retrieved from the Enzyme List, and was grouped into those related to overall reactions and biochemical transformations. Consequently, these terms were mapped onto the actual transformations taken from enzymatic reaction equations. This ontology was linked to Gene Ontology (GO) and EC numbers, allowing the extraction of common partial reaction characteristics from given sets of orthologous genes and the elucidation of possible enzymes from the given transformations. Further future development of the PIERO ontology should enhance the Enzyme List to promote the integration of genomics and metabolomics.
An effective differential expression analysis of deep-sequencing data based on the Poisson log-normal model
Authors: Wu Jun , Zhao Xiaodong , Lin Zongli , Shao Zhifeng
Published: October 2014

Tremendous amount of deep-sequencing data has unprecedentedly improved our understanding in biomedical science by digital sequence reads. To mine useful information from such data, a proper distribution for modeling all range of the count data and accurate parameter estimation are required. In this paper, we propose a method, called "DEPln," for differential expression analysis based on the Poisson log-normal (PLN) distribution with an accurate parameter estimation strategy, which aims to overcome the inconvenience in the mathematical analysis of the traditional PLN distribution. The performance of our proposed method is validated by both synthetic and real data. Experimental results indicate that our method outperforms the traditional methods in terms of the discrimination ability and results in a good tradeoff between the recall rate and the precision. Thus, our work provides a new approach for gene expression analysis and has strong potential in deep-sequencing based research.
Action Petri Net for Specifying Robot Motions
Authors: Choi Jongmyung , Lee Youngho , Ryoo Young-Jae , Choi Jongsun , Choi Jaeyoung
Published: October 2014

Smart robots and smart services using robots are promising research fields in academia and industry. However, those smart services are based on basic motions of the robot, such as grabbing objects, and moving them to a designated place. In this paper, we propose a way to produce new motions without programming, from existing motions, through a motion composition method. Our motion composition method utilizes an Action Petri net, which is a variance of a Petri net, with both interpolation and composition operations on a transition. In the Action Petri net, a place is a posture or a moving action of a robot, and it is represented as a diagonal matrix with the robot's joint motor values. Robot motions can be generated from one posture to another posture, and from composing different postures and moving actions. All operations performed to generate new motions are carried out as matrix manipulation operations. Our approach provides a formal method to generate new motions from existing motions, and a practical method to create new motions in low level motion control, without programming.
Symmetry operators and separation of variables for Dirac's equation on two-dimensional spin manifolds with external fields
Authors: Fatibene Lorenzo , McLenaghan Raymond G. , Rastelli Giovanni
Published: October 2014

The second-order symmetry operators that commute with the Dirac operator with external vector, scalar and pseudo-scalar potentials are computed on a general two-dimensional spin manifold. It is shown that the operator is defined in terms of Killing vectors, valence two Killing tensors and scalar fields defined on the background manifold. The commuting operator that arises from a non-trivial Killing tensor is determined with respect to the associated system of Liouville coordinates and compared to the second-order operator that obtained from the unique separation scheme associated with such operators. It is shown by the study of several examples that the operators arising from these two approaches coincide.
Population Biology of Aging in the Wild
Authors: Roach Deborah A. , Carey James R.
Published: October 2014

Empirical studies reveal aging occurs in wild populations. Consideration of the ecological and evolutionary consequences of these findings is critical for many areas of research, including life-history evolution, sexual selection, behavior, and applied ecology. Variation in the patterns of age-dependent declines of phenotypic traits has been found both within and among individuals, and this raises future questions aimed at understanding what determines these trajectories across traits and across the tree of life. The presence of older, aging, individuals in populations can have transgenerational effects on offspring and can influence how individuals interact. In some species older individuals in populations can have positive impacts, influencing knowledge and leadership, postreproductive care, and population cycle stabilization. Aging and long life span also need to be recognized in an applied ecology context including management plans, vector-borne disease transmission, and ecotoxicology.
Biome Shifts and Niche Evolution in Plants
Authors: Donoghue Michael J. , Edwards Erika J.
Published: October 2014

What factors influence whether a lineage can successfully transition into a new biome, and why have some biome shifts been more frequent than others? To orient this line of research we develop a conceptual framework in which the likelihood of a biome shift is a function of (a) exposure to contrasting environments over time, (b) the evolutionary accessibility of relevant adaptations, and (c) changing biotic interactions. We evaluate the literature on biome shifts in plants in relation to a set of hypotheses on the size, connectedness, and absolute age of biomes, as well as on the adaptability of particular lineages and ecological interactions over time. We also critique the phylogenetic inference of past biomes and a “global” model-based approach to biome evolution. More robust generalizations about biome shifts will require detailed studies of well-sampled and well-resolved clades, accounting for changes in the relevant abiotic and biotic factors through time.
Dynamic Stall in Pitching Airfoils: Aerodynamic Damping and Compressibility Effects
Authors: Corke Thomas C. , Thomas Flint O.
Published: October 2014

Dynamic stall is an incredibly rich fluid dynamics problem that manifests itself on an airfoil during rapid, transient motion in which the angle of incidence surpasses the static stall limit. It is an important element of many manmade and natural flyers, including helicopters and supermaneuverable aircraft, and low–Reynolds number flapping-wing birds and insects. The fluid dynamic attributes that accompany dynamic stall include an eruption of vorticity that organizes into a well-defined dynamic stall vortex and massive excursions in aerodynamic loads that can couple with the airfoil structural dynamics. The dynamic stall process is highly sensitive to surface roughness that can influence turbulent transition and to local compressibility effects that occur at free-stream Mach numbers that are otherwise incompressible. Under some conditions, dynamic stall can result in negative aerodynamic damping that leads to limit-cycle growth of structural vibrations and rapid mechanical failure. The mechanisms leading to negative damping have been a principal interest of recent experiments and analysis. Computational fluid dynamic simulations and low-order models have not been good predictors so far. Large-eddy simulation could be a viable approach although it remains computationally intensive. The topic is technologically important owing to the desire to develop next-generation rotorcraft that employ adaptive rotor dynamic stall control.
Partial Purification and Characterization of a Heat Stable α-Amylase from a Thermophilic Actinobacteria,Streptomycessp. MSC702
Authors: Singh Renu , Kumar Vijay , Kapoor Vishal
Published: October 2014

A partial purification and biochemical characterization of the α-amylase fromStreptomycessp. MSC702 were carried out in this study. The optimum operational conditions for enzyme substrate reaction for amylolytic enzyme activity from the strain were evaluated. The optimum pH, temperature, and incubation period for assaying the enzyme were observed to be 5.0, 55°C, and 30 min, respectively. The extracellular extract was concentrated using ammonium sulfate precipitation. It was stable in the presence of metal ions (5 mM) such as K+, Co2+, and Mo2+, whereas Pb2+, Mn2+, Mg2+, Cu2+, Zn2+, Ba2+, Ca2+, Hg2+, Sn2+, Cr3+, Al3+, Ag+, and Fe2+were found to have inhibitory effects. The enzyme activity was also unstable in the presence of 1% Triton X-100, 1% Tween 80, 5 mM sodium lauryl sulphate, 1% glycerol, 5 mM EDTA, and 5 mM denaturant urea. At temperature 60°C and pH 5.0, the enzyme stability was maximum. α-amylase retained 100% and 34.18% stability for 1 h and 4 h, respectively, at 60°C (pH 7.0). The enzyme exhibited a half-life of 195 min at 60°C temperature. The analysis of kinetic showed that the enzyme hasKmof 2.4 mg/mL andVmaxof 21853.0 μmol/min/mg for soluble potato starch. The results indicate that the enzyme reflects their potentiality towards industrial utilization.
A Method of Waypoint Selection in Aerial Images for Vision Navigation
Authors: Song Lin , Cheng Yong-mei , Yu Lu , Yu Liang
Published: October 2014

We present a novel method to select waypoints from aerial images of candidate flying regions via matching suitability analysis, which is based on visual attention mechanism and feature attribute classification. At first, visual attention mechanism is used to get the saliency map of the initial image by low-rank recovery and sparse coding. The salient regions are selected to be as preparatory results with threshold constraint and nonmaxima suppression. Then we use support vector machine (SVM) to divide the preparatory results into two classes for suitable or unsuitable waypoints based on their feature attributes, which can be represented by two edge-based descriptors and two correlation-based descriptors. The experimental results show that the proposed method is valid and effective.