bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermoelectric performance of various benzo-difuran wires
Authors: Péterfalvi Csaba G. , Grace Iain , Manrique Dávid Zs. , Lambert Colin J.
Published: May 2014

Using a first principles approach to electron transport, we calculate the electrical and thermoelectrical transport properties of a series of molecular wires containing benzo-difuran subunits. We demonstrate that the side groups introduce Fano resonances, the energy of which is changing with the electronegativity of selected atoms in it. We also study the relative effect of single, double, or triple bonds along the molecular backbone and find that single bonds yield the highest thermopower, approximately 22 μV/K at room temperature, which is comparable with the highest measured values for single-molecule thermopower reported to date.
Observation and modeling of mixing-layer development in high-energy-density, blast-wave-driven shear flow
Authors: Di Stefano C. A. , Malamud G. , Henry de Frahan M. T. , Kuranz C. C. , Shimony A. , Klein S. R. , Drake R. P. , Johnsen E. , Shvarts D. , Smalyuk V. A. , Martinez D.
Published: May 2014

In this work, we examine the hydrodynamics of high-energy-density (HED) shear flows. Experiments, consisting of two materials of differing density, use the OMEGA-60 laser to drive a blast wave at a pressure of ∼50 Mbar into one of the media, creating a shear flow in the resulting shocked system. The interface between the two materials is Kelvin-Helmholtz unstable, and a mixing layer of growing width develops due to the shear. To theoretically analyze the instability's behavior, we rely on two sources of information. First, the interface spectrum is well-characterized, which allows us to identify how the shock front and the subsequent shear in the post-shock flow interact with the interface. These observations provide direct evidence that vortex merger dominates the evolution of the interface structure. Second, simulations calibrated to the experiment allow us to estimate the time-dependent evolution of the deposition of vorticity at the interface. The overall result is that we are able to choose a hydrodynamic model for the system, and consequently examine how well the flow in this HED system corresponds to a classical hydrodynamic description.
Titanium embedded cage structure formation in AlnTi+ clusters and their interaction with Ar
Authors: Torres M. B. , Vega A. , Aguilera-Granja F. , Balbás L. C.
Published: May 2014

Recently, Ar physisorption was used as a structural probe for the location of the Ti dopant atom in aluminium cluster cations, AlnTi+ [Lang et al., J. Am. Soc. Mass Spectrom. 22, 1508 (2011)]. As an experiment result, the lack of Ar complexes for n > nc determines the cluster size for which the Ti atom is located inside of an Al cage. To elucidate the decisive factors for the formation of endohedrally AlnTi+, experimentalists proposed detailed computational studies as indispensable. In this work, we investigated, using the density functional theory, the structural and electronic properties of singly titanium doped cationic clusters, AlnTi+ (n = 16–21) as well as the adsorption of an Ar atom on them. The first endohedral doped cluster, with Ti encapsulated in a fcc-like cage skeleton, appears at nc = 21, which is the critical number consistent with the exohedral-endohedral transition experimentally observed. At this critical size the non-crystalline icosahedral growth pattern, related to the pure aluminium clusters, with the Ti atom in the surface, changes into a endohedral fcc-like pattern. The map of structural isomers, relative energy differences, second energy differences, and structural parameters were determined and analyzed. Moreover, we show the critical size depends on the net charge of the cluster, being different for the cationic clusters (nc = 21) and their neutral counterparts (nc = 20). For the \documentclass[12pt]{minimal}\begin{document}${\rm Al_{\rm n}Ti^+\,{\cdot}\,Ar}$\end{document} Al n Ti +· Ar complexes, and for n < 21, the preferred Ar adsorption site is on top of the exohedral Ti atom, with adsorption energy in very good agreement with the experimental value. Instead, for n = 21, the Ar adsorption occurs on the top an Al atom with very low absorption energy. For all sizes the geometry of the AlnTi+ clusters keeps unaltered in the Ar-cluster complexes. This fact indicates that Ar adsorption does not influence the cluster structure, providing support to the experimental technique used. For nc = 21, the smallest size of endohedral Ti doped cationic clusters, the Ar binding energy decreases drastically, whereas the Ar-cluster distance increases substantially, point to Ar physisorption, as assumed by the experimentalists. Calculated Ar adsorption energies agree well with available experimental binding energies.
Strongly asymmetric discrete Painlevé equations: The additive case
Authors: Grammaticos B. , Ramani A. , Tamizhmani K. M. , Tamizhmani T. , Satsuma J.
Published: May 2014

We examine a class of discrete Painlevé equations which present a strong asymmetry. These equations can be written as a system of two equations, the right-hand-sides of which do not have the same functional form. We limit here our investigation to two canonical families of the Quispel-Roberts-Thompson (QRT) classification both of which lead to difference equations. Several new integrable discrete systems are identified.
Quantification and comparison of low frequency microparticle collection mechanism in an open rectangular chamber
Authors: Agrawal Prashant , Gandhi Prasanna S. , Neild Adrian
Published: May 2014

Low frequency actuations can be used in open fluid systems to manipulate particles at the solid-liquid interface. The generation of capillary waves at resonance at the liquid-air interface results in the collection of particles over multiple cycles. A simulated flow field for a rectangular chamber undergoing vertical vibrations is used, along with a particle tracing algorithm, to track the movement of particles at different regions in the chamber; these data have been supported by experimental findings. Particle motion over a cycle has been characterized for this system and compared with the collection observed in horizontally actuated chambers. The relationship between collection behavior and a range of different particle and fluid field parameters is presented qualitatively and quantitatively.
Evidence of significant down-conversion in a Si-based solar cell using CuInS2/ZnS core shell quantum dots
Authors: Gardelis Spiros , Nassiopoulou Androula G.
Published: May 2014

We report on the increase of up to 37.5% in conversion efficiency of a Si-based solar cell after deposition of light-emitting Cd-free, CuInS2/ZnS core shell quantum dots on the active area of the cell due to the combined effect of down-conversion and the anti- reflecting property of the dots. We clearly distinguished the effect of down-conversion from anti-reflection and estimated an enhancement of up to 10.5% in the conversion efficiency due to down-conversion.
Correlation buildup during recrystallization in three-dimensional dusty plasma clusters
Authors: Schella André , Mulsow Matthias , Melzer André
Published: May 2014

The recrystallization process of finite three-dimensional dust clouds after laser heating is studied experimentally. The time-dependent Coulomb coupling parameter is presented, showing that the recrystallization starts with an exponential cooling phase where cooling is slower than damping by the neutral gas friction. At later times, the coupling parameter oscillates into equilibrium. It is found that a large fraction of cluster states after recrystallization experiments is in metastable states. The temporal evolution of the correlation buildup shows that correlation occurs on even slower time scale than cooling.
Challenging the Rhetoric of Stigmatization: The Benefits of Concentrated Poverty in Toronto's Regent Park
Authors: August Martine
Published: May 2014

This paper analyzes the impacts of territorial stigmatization on the experiences and life strategies of residents of Regent Park, Canada's first and largest public housing estate. It centers on how discourses of isolation, disorganization, and danger (based on imported theories and depictions of life in social housing developed in a very different time and place than the Canadian inner city) have served to justify the state-driven gentrification of public housing via ‘socially mixed’ redevelopment. Drawing on semistructured, in-depth interviews with over thirty tenants, this paper offers a counternarrative documenting the many benefits and advantages of living in an area of ‘concentrated poverty’. It reveals that tenants have deep attachments to Regent Park despite its reputation, and enjoy a strong sense of community; they have access to dense networks of friendship and support, local amenities and convenience, and services and agencies that suit their needs. While these benefits are real, they are counteracted by the impacts of coping with a neglected physical environment resulting from welfare state retrenchment (particularly on the housing front); and coping with safety issues and drug-related activities. Socially mixed redevelopment holds questionable promise for meaningfully addressing these problems and may even diminish some of the benefits of community life.
Governing Urban Restructuring with City-Building Nonprofits
Authors: Fraser James C , Kick Edward L
Published: May 2014

Urban restructuring efforts aimed at redeveloping inner-city neighborhoods are common across the US. They typically involve coalitions of public and private actors that play complementary roles in promoting investments in locales that have been sites of disinvestment, rendering these geographies ripe for economic development and profitmaking (ie, gentrification). Nonprofits are not generally regarded as central players in these initiatives, although they often serve community-development functions for low-income populations living in impoverished city spaces. In this paper we draw on the concept of the shadow state and Foucault's theory of governmentality to examine a city-building nonprofit created by a public–private growth coalition to execute the redevelopment of urban space and, as an integral part, manage neighborhood resident participation in these efforts. As residents began to see themselves as agents of neighborhood change, they came into conflict with the revitalization objectives of the nonprofit's funders. And, while many residents actively challenged the direction that the neighborhood initiative took in focusing on housing redevelopment for more affluent populations, a core group maintained their commitment to a community building approach toward neighborhood redevelopment. Between 1998 and 2014, during CIC's initiative, over half of the original residents were displaced or left as neighborhood housing values dramatically increased, rendering the area inaccessible for low-income populations.
Another Letter from the Home Office: Reading the Material Politics of Asylum
Authors: Darling Jonathan
Published: May 2014

In an era of technologically mediated modes of border enforcement, this paper focuses upon a seemingly more anachronistic mode of governmental intervention: That of the letter. Exploring the use of letters by the UK Border Agency to communicate decisions on asylum claims I argue that taking the materiality of the letter seriously demands a reworking of the politics of asylum. Drawing on ethnographic research within a UK asylum drop-in centre, the paper opens by offering a governmental reading of letters as things which define the limits of present and future actions, whilst fixing individuals to specific locations. The paper then destabilises such a reading by considering how letters are understood through material-discursive entanglements of things, discourses, and spaces, such that letters are understood through, and help to constitute, different atmospheres, spaces, and subjectivities of asylum. Thus I argue that it is by taking seriously the connections between materials, discourses, and affective states that we might critically interrogate framings of the state as an oppressive force shaping the lives of those seeking asylum.
Dietary chromium picolinate of varying particle size improves carcass characteristics and insulin sensitivity in finishing pigs fed low- and high-fat diets
Authors: Hung A. T. , Leury B. J. , Sabin M. A. , Lien T. F. , Dunshea F. R.
Published: May 2014

The aim of the present study was to evaluate the effect of the different-sized particles of chromium (Cr) picolinate (CrPic) and dietary fat on growth performance, carcass traits and insulin sensitivity of finishing pigs. Ninety-six Large White × Landrace gilts were stratified on bodyweight, housed in pens of three pigs and then, on a pen basis, randomly allocated to eight treatment groups in a 2 × 4 factorial design for 6 weeks. The respective factors were dietary fat (2.2% or 5.7%) and dietary CrPic (0 mg/kg, 400 mg/kgnormal-size CrPic, 400 mg/kg 1-μm CrPic (μCrPic), or 400 mg/kg 100-nm CrPic (nCrPic)). Over the first 21 days, average daily gain (ADG) was increased by dietary CrPic (0.94 vs 1.01 kg/day, P = 0.021), although there was no difference (P = 0.17) between the CrPic particle sizes. High dietary fat also increased ADG over this period (0.96 vs 1.03 kg/day, P = 0.013). However, the responses to both dietary CrPic and fat diminished over time and so there was no effect of CrPic (P = 0.35) or fat (P = 0.93) on ADG over the full 42 days. Dietary CrPic increased carcass weight and muscle depth and decreased P2 backfat. Furthermore, dietary Cr decreased plasma insulin (7.66 vs 5.09 mU/L, P = 0.018) and the homeostatic model assessment (1.25 vs 0.82, P = 0.009), indicating an improvement in insulin sensitivity. In conclusion, dietary Cr can increase ADG and improve carcass traits and insulin sensitivity in lean pigs. There were few differences among particle sizes, possibly because the response to dietary CrPic may already be maximised at 400 mg/kg.
An Unexpected Coupling Reaction of 8-Quinolinolate at Elevated Temperature
Authors: Deacon Glen B. , Forsyth Craig M. , Gazukin Olga , Junk Peter C. , Meyer Gerd , Sierau Jennyfer , Turner David R.
Published: May 2014

Reactions of 8-hydroxyquinoline (HOQ) with elemental rare-earth and transition metal combinations or alloys at 200–300°C yielded a variety of complexes, albeit in very low yields, including two structurally characterised homometallic complexes containing an unexpected biquinolinolate ligand. Reaction of HOQ with SmCo5 alloy gives rise to the complexes [SmCo2(OQ)7] (1), [Co4(OQ)4(BQ)2] (2), and [Sm3(OQ)5(BQ)2(H2O)] (3Sm), where BQ is 2,7′-biquinoline-8,8′-diolate, resulting from an unusual coupling reaction between two OQ/HOQ species at the 2 and 7′ positions. Complexes 1–3 and HOQ co-crystal 2·2HOQ were isolated as single crystals from separate reactions although formation of other products under the reaction conditions used was likely. Analogues of 3Sm with erbium and ytterbium were obtained using respective rare-earth metal filing in combination with nickel powder. Reaction involving cobalt powder only, without any rare-earth metals, yielded a homoleptic complex containing only the 8-quinolinolate ligand i.e. [Co4(OQ)8] (4). These results highlight the rewards, in terms of rich synthetic chemistry, and pitfalls, in terms of yield and isolation, of the pseudo-solid state synthetic approach using 8-quinolinolate ligands.
Effects of banded ammonia and urea fertiliser on soil properties and the growth and yield of wheat
Authors: Angus J. F. , Gupta V. V. S. R. , Pitson G. D. , Good A. J.
Published: May 2014

Experiments conducted over three seasons in southern New South Wales tested the effects of concentrating anhydrous ammonia (AA) and urea fertiliser in bands occupying ~3.5% of the topsoil volume. Yield responses to applied nitrogen (N) were small or negative in a drought but larger (17 kg grain kg–1 N fertiliser) in favourable seasons. There was no consistent difference between AA and urea effects on yield, grain protein or efficiency of fertiliser-N recovery, and there were no consistent differences arising from banding depth or application time. Gaseous loss of ammonia to the atmosphere was negligible from urea granules or AA injected into the soil as gas or liquid. Soil ammonium concentration was >700 μg N g–1 in bands of ~5 cm diameter when measured 6 days after AA application but halved within 5 weeks due to nitrification. Within 1 day of banding AA or urea at sowing, pHwater in the bands rose from 6 to 8.5, leading to transient changes in microbial activity and populations. Immediately after banding, microbial biomass carbon and numbers of protozoa fell by about half, but numbers of ammonia- and nitrite-oxidisers were unchanged. Five weeks later, microbial biomass carbon and protozoa had partly recovered whereas numbers of ammonia- and nitrite-oxidisers increased 5–10-fold. After 7 months, there was a small reduction in microbial diversity in the bands, shown by analysis of fatty acid methyl esters. Seedling growth was slower where N fertiliser was applied in concentrated bands than when mixed throughout the topsoil, supporting previous research showing that roots avoid bands of highly concentrated ammonium. Banding thus provided a slow-release form of N to wheat crops, thereby reducing excessive seedling growth and the risks of haying-off.
Comparing alternatives for combining invertebrate and diatom assessment in stream quality classification
Authors: Mendes Tânia , Calapez Ana Raquel , Elias Carmen L. , Almeida Salomé F. P. , Feio Maria João
Published: May 2014

The present study aimed to determine if a predictive model integrating freshwater assemblages from different trophic levels (macroinvertebrates and diatoms) produces a more sensitive assessment of stream health than single-assemblage assessments combined a posteriori. For this purpose, individual and combined models based on two approaches (BEAST and RIVPACS) were developed for Portuguese streams: two for diatoms; two for macroinvertebrates; and two combining diatoms and macroinvertebrates as a single community. Twenty-three sites affected by organic contamination, industrial effluents and mine drainage were evaluated with the predictive models and also by the official biotic indices used in Portugal. The sensitivity of the RIVPACS assessment to disturbance was improved by the a priori combination of diatoms and macroinvertebrates, whereas for BEAST the a posteriori approaches were slightly more sensitive. Diatom and invertebrate indices combined a posteriori performed better than single-assemblage indices but with lower sensitivity than combined models. We conclude that the a priori combination of the two biological assemblages is valuable (more sensitive to disturbance) for the RIVPACS approach and that the a posteriori combination of assessments for individual biological elements may not always provide the most realistic indication of stream health.
Fringe-mediated extension of
O
-linked fucose in the ligand-binding region of Notch1 increases binding to mammalian Notch ligands
Authors: Taylor Paul , Takeuchi Hideyuki , Sheppard Devon , Chillakuri Chandramouli , Lea Susan M. , Haltiwanger Robert S. , Handford Penny A.
Published: May 2014

Significance

The Notch pathway is a crucial metazoan cell–cell signaling pathway. The Notch receptor is regulated by
O
-glycosylation, a sugar modification that involves a series of enzyme-catalyzed additions to residues within EGF domains. Here, we demonstrate that the Fringe enzyme modification enhances the affinity of a receptor fragment for its ligand. X-ray crystallographic analysis demonstrates that the backbone structure does not change as a consequence of the modification, suggesting that the Fringe addition directly enhances ligand binding, although indirect effects cannot be ruled out. These data help to explain the Notch–Delta signaling increase seen in the presence of Fringe, but suggest that the inhibitory effects observed with the Jagged/Serrate ligand class are mediated by other regions of modified Notch.
Simultaneous assessment of the macrobiome and microbiome in a bulk sample of tropical arthropods through DNA metasystematics
Authors: Gibson Joel , Shokralla Shadi , Porter Teresita M. , King Ian , van Konynenburg Steven , Janzen Daniel H. , Hallwachs Winnie , Hajibabaei Mehrdad
Published: May 2014

Significance

Ecological and evolutionary investigations require accurate and high-resolution biodiversity information. Conventional morphological approaches to identifying species in species-rich tropical ecosystems are often unavailable or incapable of timely, cost-effective identification. We show that next-generation sequencing (NGS) of cytochrome c oxidase subunit I (COI) DNA barcodes can accurately detect 83.5% of individually sequenced species (corresponding to 91% of individuals) in a bulk sample of terrestrial arthropods from a Costa Rican species-rich site. Additionally, the 16S and 18S ribosomal DNA gene regions obtained also provide an assessment of the bacteria and protozoa in the bulk sample. This metasystematic approach provides the initial infrastructure for a next generation of biodiversity assessment and environmental monitoring. It can lead to more effective understanding, appreciation, and management of complex ecosystems.
A Comparison of Environmental Contamination by Patients Infected or Colonized with Methicillin-Resistant Staphylococcus aureus or Vancomycin-Resistant Enterococci: A Multicenter Study
Authors: Knelson Lauren P. , Williams David A. , Gergen Maria F. , Rutala William A. , Weber David J. , Sexton Daniel J. , Anderson Deverick J. ,   on behalf of the Centers for Disease Control and Prevention Epicenters Program
Published: May 2014

A total of 1,023 environmental surfaces were sampled from 45 rooms with patients infected or colonized with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE) before terminal room cleaning. Colonized patients had higher median total target colony-forming units (CFU) of MRSA or VRE than did infected patients (median, 25 CFU [interquartile range, 0–106 CFU] vs 0 CFU [interquartile range, 0–29 CFU]; P = .033).

Infect Control Hosp Epidemiol 2014;35(7):872–875
Positivity conjectures for Kazhdan-Lusztig theory on twisted involutions: the universal case
Authors: Marberg Eric
Published: May 2014

Let

(
W
,
S
)

(W,S)

be a Coxeter system and let

w
↦

w
∗

w \mapsto w^*

be an involution of

W
W

which preserves the set of simple generators

S
S

. Lusztig and Vogan have recently shown that the set of twisted involutions (i.e., elements

w
∈
W

w \in W

with

w

−
1

=

w
∗

w^{-1} = w^*

) naturally generates a module of the Hecke algebra of

(
W
,
S
)

(W,S)

with two distinguished bases. The transition matrix between these bases defines a family of polynomials

P

y
,
w

σ

P^\sigma _{y,w}

which one can view as “twisted” analogues of the much-studied Kazhdan-Lusztig polynomials of

(
W
,
S
)

(W,S)

. The polynomials

P

y
,
w

σ

P^\sigma _{y,w}

can have negative coefficients, but display several conjectural positivity properties of interest. This paper reviews Lusztig’s construction and then proves three such positivity properties for Coxeter systems which are universal (i.e., having no braids relations), generalizing previous work of Dyer. Our methods are entirely combinatorial and elementary, in contrast to the geometric arguments employed by Lusztig and Vogan to prove similar positivity conjectures for crystallographic Coxeter systems.
The regulator of G protein signaling (RGS) domain of G protein–coupled receptor kinase 5 (GRK5) regulates plasma membrane localization and function
Authors: Xu Hua , Jiang Xiaoshan , Shen Ke , Fischer Christopher C. , Wedegaertner Philip B.
Published: May 2014

The G protein–coupled receptor (GPCR) kinases (GRKs) phosphorylate activated GPCRs at the plasma membrane (PM). Here GRK5/GRK4 chimeras and point mutations in GRK5 identify a short sequence within the regulator of G protein signaling (RGS) domain in GRK5 that is critical for GRK5 PM localization. This region of the RGS domain of GRK5 coincides with a region of GRK6 and GRK1 shown to form a hydrophobic dimeric interface (HDI) in crystal structures. Coimmunoprecipitation (coIP) and acceptor photobleaching fluorescence resonance energy transfer assays show that expressed GRK5 self-associates in cells, whereas GRK5-M165E/F166E (GRK5-EE), containing hydrophilic mutations in the HDI region of the RGS domain, displays greatly decreased coIP interactions. Both forcing dimerization of GRK5-EE, via fusion to leucine zipper motifs, and appending an extra C-terminal membrane-binding region to GRK5-EE (GRK5-EE-CT) recover PM localization. In addition, GRK5-EE displays a decreased ability to inhibit PAR1-induced calcium release compared with GRK5 wild type (wt). In contrast, PM-localized GRK5-EE-CaaX (appending a C-terminal prenylation and polybasic motif from K-ras) or GRK5-EE-CT shows comparable ability to GRK5 wt to inhibit PAR1-induced calcium release. The results suggest a novel model in which GRK5 dimerization is important for its plasma membrane localization and function.
MgcRacGAP interacts with cingulin and paracingulin to regulate Rac1 activation and development of the tight junction barrier during epithelial junction assembly
Authors: Guillemot Laurent , Guerrera Diego , Spadaro Domenica , Tapia Rocio , Jond Lionel , Citi Sandra
Published: May 2014

The regulation of Rho-family GTPases is crucial to direct the formation of cell–cell junctions and tissue barriers. Cingulin (CGN) and paracingulin (CGNL1) control RhoA activation in epithelial cells by interacting with RhoA guanidine exchange factors. CGNL1 depletion also inhibits Rac1 activation during junction assembly. Here we show that, unexpectedly, Madin–Darby canine kidney epithelial cells depleted of both CGN and CGNL1 (double-KD cells) display normal Rac1 activation and tight junction (TJ) formation, despite decreased junctional recruitment of the Rac1 activator Tiam1. The expression of the Rac1 inhibitor MgcRacGAP is decreased in double-KD cells, and the barrier development and Rac1 activation phenotypes are rescued by exogenous expression of MgcRacGAP. MgcRacGAP colocalizes with CGN and CGNL1 at TJs and forms a complex and interacts directly in vitro with CGN and CGNL1. Depletion of either CGN or CGNL1 in epithelial cells results in decreased junctional localization of MgcRacGAP but not of ECT2, a centralspindlin-interacting Rho GEF. These results provide new insight into coordination of Rho-family GTPase activities at junctions, since apical accumulation of CGN and CGNL1 at TJs during junction maturation provides a mechanism to spatially restrict down-regulation of Rac1 activation through the recruitment of MgcRacGAP.
Systematic spatial mapping of proteins at exocytic and endocytic structures
Authors: Larson Ben T. , Sochacki Kem A. , Kindem Jonathan M. , Taraska Justin W.
Published: May 2014

Vesicular secretion (exocytosis) involves the release and then compensatory recycling of vesicle components through endocytosis. This fundamental cellular process is controlled by the coordinated assembly and interactions of dozens of proteins at the plasma membrane. Understanding the molecular composition of individual exocytic and endocytic structures and their organization across the plasma membrane is critical to understanding the behavior and regulation of these two cellular processes. Here we develop a high-resolution and high-throughput fluorescence imaging–based approach for the unbiased mapping of 78 proteins at single exocytic vesicles and endocytic structures in neuroendocrine PC12 cells. This analysis uses two-color single-frame images to provide a systems-level map of the steady-state distributions of proteins at individual exocytic and endocytic structures in the cell. Along with this quantitative map, we find that both calcium-regulated exocytic vesicles (dense core vesicles) and endocytic structures (clathrin-coated structures) and the proteins associated with these structures exhibit a random spatial distribution in unstimulated neuroendocrine PC12 cells. This approach is broadly applicable for quantitatively mapping the molecular composition and spatial organization of discrete cellular processes with central molecular hubs.
Environment and the Natural World
Authors: Cooper Alix
Published: May 2014

Over the course of the early modern period, Europeans came to look at, engage with, and even transform nature and the environment in new ways, as they studied natural objects, painted landscapes, drew maps, built canals, cut down forests, and transferred species from one continent to another. The term “nature” meant many things during this period, from the inmost essence of something to those parts of the world that were nonhuman, such as the three famous “kingdoms” of nature: the animal, the vegetable, and the mineral. This article focuses on nature in this latter sense and broadens it out to include more recent understandings of the modern term “environment,” so as to encompass not only plants, animals, and rocks but also entire landscapes. Scholars from a wide variety of fields, ranging from the histories of science, art, and literature through historical geography, historical archeology, historical ecology, and landscape history, have long been interested in issues related to the environment and the natural world; more recently, they have been joined by practitioners of “environmental history” and additional branches of the environmental humanities and social sciences, who have drawn on these preexisting approaches and brought still further perspectives to the table.
History of Linguistics
Authors: Joseph John E.
Published: May 2014

The term linguistics is a product of the nineteenth century, as are the academic field and the form of enquiry that it designates. This enquiry is however continuous with modes of analysis that date back to ancient times, as practiced in various traditions in Asia and Europe (together with the African parts of the Alexandrian Empire). The History of Linguistics itself has mid-19th-century beginnings and has taken its scope as ranging over the whole of this ancient-to-modern continuum. Given that language and its analysis have played a part in every academic area, and that modern linguistics has interests that overlap with those of anthropology, artificial intelligence, education, informatics, legal theory, literary criticism, philosophy, psychology, semiotics, sociology, and other subjects, it is not obvious where the boundaries of the History of Linguistics lie, and scholarly disputes over where to draw them are not uncommon. This bibliography will focus on the prototypical areas of language analysis, while not excluding those areas that, if more peripheral, have nevertheless had a considerable impact on what linguists think and do.
Venezuelan Americans
Authors: Troconis Irina , Stavans Ilan
Published: May 2014

The term “Venezuelan Americans” refers to US citizens who trace their heritage, or part of their heritage, to Venezuela. Traditionally a “receiving country,” welcoming immigrants from all over the world, Venezuela has slowly become a “sending country,” with the United States being the preferred destination of many of its emigrants. The significant wave of migration toward the United States started during the 1980s, when Venezuelans experienced economic crisis and political discontent as a result of the decline of the oil prices. The wave of migration steadily increased during the 1990s, when the country witnessed two coups, a presidential impeachment, another major financial crisis, and the election of Hugo Chávez. Chávez’s regime brought along important changes to the traditional party system and led to an environment of economic and institutional crisis, personal insecurity, and political violence that forced many Venezuelans to look for a better life in countries such as the United States, Canada, and Spain. By 2000, Venezuelans ranked second as the fastest-growing Latino population subgroup in the United States, increasing to more than twice its size by 2010, which shows that, under Chávez’s regime, the migration wave suffered an unusual increase. In 2011, a record number of 6,853 Venezuelans obtained the American citizenship. Nevertheless, Venezuela is one of the countries with the lowest rate of naturalization, because many of its emigrants see their stay in the United States as provisional. The US Census Briefs from 1990, 2000, and 2010 consistently characterize the Venezuelan immigrant population as typically young and well educated, with training in skilled jobs and a high average annual income. They are located mainly in the South and more specifically in Florida. Only recently has this population received attention from sociological studies and academic articles; most research on the topic of migration and ethnicity in the United States has traditionally focused on Mexican and Cuban immigrants, who constitute the majority of the Latino population. Moreover, studies from the 1970s and 1980s and some from the 1990s group Venezuelans under the category of “South Americans,” limiting access to information specifically related to this population. Although there are now more articles and chapters that focus exclusively on Venezuelan Americans, the information available about this group is scarce and dispersed. This article’s purpose is to construct a bibliography that brings together the most-important sources available on the topic. The hope is that this article will help current research on Venezuelan Americans and will encourage more research to be done in areas where important information is lacking.
Poverty and Living Standards since 1949
Authors: Piazza Alan
Published: May 2014

Trends in poverty and living standards in China were mixed during the period from 1949 to 1978. In the 1950s and 1970s, the more egalitarian distribution and increased production of food, combined with improvements in access to basic education and public health, reduced poverty, and improved living standards. During the Great Leap Forward period (1959–1962), however, the collapse of food production and the failure to take corrective measures led to widespread famine of historic proportions and a sharp decline in living standards. China’s subsequent tremendous success in reducing extreme poverty during the economic reform period (1978–2013) is widely recognized. World Bank estimates indicate that the number of absolute poor (that is, those people consuming less than $1.25 per day in Purchasing Power Parity terms) in China declined by more than 600 million from about 835 million in 1981 to 173 million in 2008. Based on a much more austere poverty line, official government estimates indicate that the number of poor was significantly lower than the World Bank estimates throughout the economic reform period but confirm a similar sharp decline in poverty over these years. Moreover, these consumption- and income- based estimates of the decline in poverty are matched by broad-based improvements in nutritional status, educational attainment, health, and other indicators of well-being since the late 1990s. While there is consensus on the massive reduction in poverty in China during the economic reform period, there is continuing debate on the effectiveness of the government’s poverty reduction program. Other important issues include the deterioration of access to basic education and public health in rural areas resulting from the dissolution of the commune system during 1978–1984 and the widening of income disparity beginning in the mid-1980s. In addition, while very large-scale Labor Migration has made a massive contribution to economic growth and poverty reduction, there are also many well-recognized adverse social consequences to this demographic trend. There is also concern that ethnic minority people, people with disabilities, the elderly, and women are known to represent disproportionately large shares of China’s remaining absolute poor and suffer the greatest deprivation. China has actively collaborated with a host of international partners on its poverty reduction program during the economic reform period. Consistent with China’s strong economic growth, the Chinese government has begun the transition from development aid recipient to aid donor, and is expanding its role in international poverty reduction and development work. This article was compiled with the assistance of Wang Yilin.
Development of a Quantitative Polymerase Chain Reaction Detection Protocol for Cercospora kikuchii in Soybean Leaves and Its Use for Documenting Latent Infection as Affected by Fungicide Applications
Authors: Chanda A. K. , Ward N. A. , Robertson C. L. , Chen Z.-Y. , Schneider R. W.
Published: May 2014

Cercospora leaf blight (CLB) of soybean, caused by Cercospora kikuchii, is a serious disease in the southern United States. A sensitive TaqMan probe-based real-time quantitative polymerase chain reaction (qPCR) assay was developed to specifically detect and quantify C. kikuchii in naturally infected soybean plants. The sensitivity was 1 pg of genomic DNA, which was equivalent to about 34 copies of genome of C. kikuchii. Using this qPCR assay, we documented a very long latent infection period for C. kikuchii in soybean leaves beginning at the V3 growth stage (as early as 22 days after planting). The levels of biomass of C. kikuchii remained low until R1, and a rapid increase was detected from the R2/R3 to R4/R5 growth stages shortly before the appearance of symptoms at R6. The efficacy of various fungicide regimens under field conditions also was evaluated over a 3-year period using this qPCR method. Our results showed that multiple fungicide applications beginning at R1 until late reproductive stages suppressed the development of C. kikuchii in leaves and delayed symptom expression. Different fungicide chemistries also had differential effects on the amount of latent infection and symptom expression during late reproductive growth stages.
Testing the optimality properties of a dual antibiotic treatment in a two-locus, two-allele model
Authors: Peña-Miller Rafael , Fuentes-Hernandez Ayari , Reding Carlos , Gudelj Ivana , Beardmore Robert
Published: May 2014

Mathematically speaking, it is self-evident that the optimal control of complex, dynamical systems with many interacting components cannot be achieved with ‘non-responsive’ control strategies that are constant through time. Although there are notable exceptions, this is usually how we design treatments with antimicrobial drugs when we give the same dose and the same antibiotic combination each day. Here, we use a frequency- and density-dependent pharmacogenetics mathematical model based on a standard, two-locus, two-allele representation of how bacteria resist antibiotics to probe the question of whether optimal antibiotic treatments might, in fact, be constant through time. The model describes the ecological and evolutionary dynamics of different sub-populations of the bacterium
Escherichia coli
that compete for a single limiting resource in a two-drug environment. We use
in vitro
evolutionary experiments to calibrate and test the model and show that antibiotic environments can support dynamically changing and heterogeneous population structures. We then demonstrate, theoretically and empirically, that the best treatment strategies should adapt through time and constant strategies are not optimal.
Ribosomal frameshifting used in influenza A virus expression occurs within the sequence UCC_UUU_CGU and is in the +1 direction
Authors: Firth A. E. , Jagger B. W. , Wise H. M. , Nelson C. C. , Parsawar K. , Wills N. M. , Napthine S. , Taubenberger J. K. , Digard P. , Atkins J. F.
Published: May 2014

Programmed ribosomal frameshifting is used in the expression of many virus genes and some cellular genes. In eukaryotic systems, the most well-characterized mechanism involves –1 tandem tRNA slippage on an X_XXY_YYZ motif. By contrast, the mechanisms involved in programmed +1 (or −2) slippage are more varied and often poorly characterized. Recently, a novel gene, PA-X, was discovered in influenza A virus and found to be expressed via a shift to the +1 reading frame. Here, we identify, by mass spectrometric analysis, both the site (UCC_UUU_CGU) and direction (+1) of the frameshifting that is involved in PA-X expression. Related sites are identified in other virus genes that have previously been proposed to be expressed via +1 frameshifting. As these viruses infect insects (chronic bee paralysis virus), plants (fijiviruses and amalgamaviruses) and vertebrates (influenza A virus), such motifs may form a new class of +1 frameshift-inducing sequences that are active in diverse eukaryotes.
Asymptotic behaviour of Stokes flow in a thin domain with a moving rough boundary
Authors: Fabricius J. , Koroleva Y. O. , Tsandzana A. , Wall P.
Published: May 2014

We consider a problem that models fluid flow in a thin domain bounded by two surfaces. One of the surfaces is rough and moving, whereas the other is flat and stationary. The problem involves two small parameters
ϵ
and
μ
that describe film thickness and roughness wavelength, respectively. Depending on the ratio λ=
ϵ
/
μ
, three different flow regimes are obtained in the limit as both of them tend to zero. Time-dependent equations of Reynolds type are obtained in all three cases (Stokes roughness, Reynolds roughness and high-frequency roughness regime). The derivations of the limiting equations are based on formal expansions in the parameters
ϵ
 and 
μ
.
Is discrimination enhanced at the boundaries of perceptual categories? A negative case
Authors: Danilova M. V. , Mollon J. D.
Published: May 2014

The human visual system imposes discrete perceptual categories on the continuous input space that is represented by the ratios of excitations of the cones in the retina. Is discrimination enhanced at the boundaries between perceptual hues, in the way that discrimination may be enhanced at the boundaries between speech sounds in hearing? In the chromaticity diagram, the locus of unique green separates colours that appear yellowish from those that appear bluish. Using a two-alternative spatial forced choice and an adapting field equivalent to the Daylight Illuminant D65, we measured chromatic discrimination along lines orthogonal to the locus of unique green. In experimental runs interleaved with these performance measurements, we obtained estimates of the phenomenological boundary from the same observers. No enhancement of objectively measured discrimination was observed at the category boundary between yellowish and bluish hues. Instead, thresholds were minimal at chromaticities where the ratio of long-wave to middle-wave cone excitation was the same as that for the background adapting field.
Streptococcus
cuniculi sp. nov., isolated from the respiratory tract of wild rabbits
Authors: Vela A. I. , Sánchez del Rey V. , Zamora L. , Casamayor A. , Domínguez L. , Fernández-Garayzábal J. F.
Published: May 2014

Biochemical and molecular genetic studies were performed on four unknown Gram-stain-positive, catalase-negative, coccus-shaped organisms isolated from tonsils (n = 3) and nasal samples (n = 1) of four wild rabbits. The micro-organism was identified as a streptococcal species based on its cellular morphological and biochemical tests. Comparative 16S rRNA gene sequencing confirmed its identification as a member of the genus

Streptococcus

, but the organism did not correspond to any recognized species of this genus. The closest phylogenetic relative of the unknown cocci from wild rabbits was

Streptococcus acidominimus

NCIMB 702025T (97.9 % 16S rRNA gene sequence similarity). rpoB and sodA sequence analysis of the novel isolate showed interspecies divergence of 16.2 % and 20.3 %, respectively, from the type strain of its closest 16S rRNA gene phylogenetic relative,

S. acidominimus

. The novel bacterial isolate could be distinguished from the type strain of

S. acidominimus

by several biochemical characteristics, such as the production of esterase C4, acid phosphatase and naphthol-AS-BI-phosphohydrolase and acidification of different sugars. Based on both phenotypic and phylogenetic findings, it is proposed that the unknown bacterium be classified as a novel species of the genus

Streptococcus

, Streptococcus cuniculi sp. nov. The type strain is NED12-00049-6BT ( = CECT 8498T = CCUG 65085T).
Preparation of Cheonggukjang added onion (Allium cepa L.) and its antioxidative activity
Authors: Lee Minji , Lee Yu Geon , Cho Jung-Il , Na Kwang-Chool , Hwang Eom Ji , Kim Mi Seung , Moon Jae-Hak
Published: May 2014

Yellow and black soybean Cheonggukjangs (YBSC) prepared with an addition of onion (Allium cepa L.) in different contents (0, 5, 10, 20, and 30%, w/w) were manufactured, and the sensory evaluation was carried out. The optimum addition ratio of onion was determined to be 20%. Total phenolic and flavonoid contents of YBSC prepared with an addition of onion were higher than those of the YBSC prepared without an onion. In addition, YBSC prepared with an addition of onion showed higher 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activities than those prepared without an onion. Furthermore, rat blood plasma 1 hour after oral administration of YBSC prepared with an onion was more effective in suppressing the accumulation of cholesteryl ester hydroperoxide than those prepared without onion and control. These results indicated that the consumption of the YBSC prepared with onion may contribute to the antioxidant defense in vivo.
Monitoring and risk assessment of pesticide in school foodservice products in seoul, Korea
Authors: Seo Young-Ho , Moon Kwang-Deog
Published: May 2014

We tested for residual pesticide levels in school foodservice agricultural products in Seoul, Korea from 2010 to 2012. A total of 316 samples of 23 different types of agricultural products were analyzed via gas chromatography-nitrogen phosphate detector (GC-NPD), an electron capture detector (GC-μECD), a mass spectrometry detector (GC-MSD), and a high performance liquid chromatography-ultraviolet detector (HPLC-UV). We used multi-analysis methods to analyze 185 different pesticide types. Among the selected agricultural products, residual pesticides were detected in 26 samples (8.2%), of which 6 samples (1.9%) exceeded the Korea Maximum Residue limits (MRLs). We detected pesticide residue in more than 65% of the Chwinamul, while 6 among 9 analyzed samples contained pesticide residue, and 1 sample exceeded the Korea MRLs. Among the 185 kinds of pesticides that we have tested, 18 were detected, while 7 of them were detected more than twice. Data obtained were then used for estimating the potential health risks associated with the exposures to these pesticides. The most critical commodity is carbofuran in the perilla leaves, which has contributed 3.8% to the hazard index (HI). These results showed that the detected pesticides could not be considered as a serious public health problem. Nevertheless, constant supervision is recommended.
Sequence co-evolution gives 3D contacts and structures of protein complexes
Authors: Hopf Thomas A. , Schärfe Charlotta P.I. , Rodrigues João P.G.L.M. , Green Anna G. , Sander Chris , Bonvin Alexandre M.J.J. , Marks Debora S.
Published: May 2014

Protein-protein interactions are fundamental to many biological processes. Experimental screens have identified tens of thousands of interactions and structural biology has provided detailed functional insight for select 3D protein complexes. An alternative rich source of information about protein interactions is the evolutionary sequence record. Building on earlier work, we show that analysis of correlated evolutionary sequence changes across proteins identifies residues that are close in space with sufficient accuracy to determine the three-dimensional structure of the protein complexes. We evaluate prediction performance in blinded tests on 76 complexes of known 3D structure, predict protein-protein contacts in 32 complexes of unknown structure, and demonstrate how evolutionary couplings can be used to distinguish between interacting and non-interacting protein pairs in a large complex. With the current growth of sequence databases, we expect that the method can be generalized to genome-wide elucidation of protein-protein interaction networks and used for interaction predictions at residue resolution.