bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial distributions of secondary minerals in the Martian meteorite MIL 03346,168 determined by Raman spectroscopic imaging
Authors: Ling Zongcheng , Wang Alian
Published: May 2015

Miller Range (MIL) 03346 is a nakhlite meteorite that has been extensively studied due to its unique complex secondary mineral phases and their potential implications for the hydrologic history of Mars. We conducted a set of Raman spectroscopic and Raman imaging studies of MIL 03346,168, focusing on the secondary mineral phases and their spatial distributions, with a goal to better understand the possible processes by which they were generated on Mars. This study revealed three types of calcium sulfates, a solid solution of (K, Na)‐jarosite and two groups of hydrated species with low crystallinity (HSLC) in the veins and/or mesostasis areas of the meteorite. The most abundant Ca‐sulfate is bassanite that suggests two possible paths for its direct precipitation from a Ca‐S‐H2O brine, either having low water activity or with incomplete development (producing bassanite with gypsum microcrystals) on Mars. The second most abundant Ca‐sulfate is soluble γ‐CaSO4 which raises a new question on the origins of this phase in the Martian meteorite, since γ‐CaSO4 readily hydrates in the laboratory but is apparently stable in Atacama Desert. The close spatial relationship of (K, Na)‐jarosite solid solutions with rasvumite (KFe2S3), magnetite, HSLC, and fine‐grained low‐crystallinity alkali feldspar in mesostasis suggests a potential in situ formation of mesostasis jarosite from these Fe‐K,Na‐S‐O‐H2O species.
Predicting the magnetic vectors within coronal mass ejections arriving at Earth: 1. Initial architecture
Authors: Savani N. P. , Vourlidas A. , Szabo A. , Mays M. L. , Richardson I. G. , Thompson B. J. , Pulkkinen A. , Evans R. , Nieves‐Chinchilla T.
Published: May 2015

The process by which the Sun affects the terrestrial environment on short timescales is predominately driven by the amount of magnetic reconnection between the solar wind and Earth's magnetosphere. Reconnection occurs most efficiently when the solar wind magnetic field has a southward component. The most severe impacts are during the arrival of a coronal mass ejection (CME) when the magnetosphere is both compressed and magnetically connected to the heliospheric environment. Unfortunately, forecasting magnetic vectors within coronal mass ejections remain elusive. Here we report how, by combining a statistically robust helicity rule for a CME's solar origin with a simplified flux rope topology, the magnetic vectors within the Earth‐directed segment of a CME can be predicted. In order to test the validity of this proof‐of‐concept architecture for estimating the magnetic vectors within CMEs, a total of eight CME events (between 2010 and 2014) have been investigated. With a focus on the large false alarm of January 2014, this work highlights the importance of including the early evolutionary effects of a CME for forecasting purposes. The angular rotation in the predicted magnetic field closely follows the broad rotational structure seen within the in situ data. This time‐varying field estimate is implemented into a process to quantitatively predict a time‐varying Kp index that is described in detail in paper II. Future statistical work, quantifying the uncertainties in this process, may improve the more heuristic approach used by early forecasting systems.
Arabidopsis: Flower Development and Patterning
Authors: Krizek Beth A
Published: May 2015

The development of flowers and floral organs is directed by intricate genetic programmes, many aspects of which appear to be shared among angiosperms. Early acting genes establish floral meristem identity in flower primordia initiated at the periphery of the inflorescence meristem. Later, floral organ primordia arise at precise positions within these floral meristems and take on one of the four distinct identities (sepals, petals, stamens and carpels). The ABCE model, supported by both molecular and genetic experiments inArabidopsis, explains how a small number of regulatory genes (called floral homeotic genes or floral organ identity genes) act in different combinations to specify these different organ types. The floral organ identity genes encode transcription factors that form distinct higher order protein complexes in different regions of a flower primordium to control the expression of target genes responsible for organogenesis.

Key Concepts

Lateral organs produced by the shoot apical meristem during reproductive development acquire their identity as flowers through the action of floral meristem identity genes such asLEAFYandAPETALA1.

The identities of each of the four organ types of a flower (sepal, petal, stamen and carpel) is conferred by a unique combination of floral organ identity gene activities, referred to as class A, B, C and E in the ABCE model.

The activities of the class A, B and C genes are restricted to particular regions within a developing flower primarily, but not exclusively, through transcriptional regulation.

The MADS domain transcription factors encoded by the class A, B, C and E genes form unique tetrameric transcriptional regulatory complexes in cells of each floral whorl.

The transcriptional regulatory complexes formed by the A, B, C and E proteins regulate distinct sets of genes at different stages of flower development.

Many aspects of the genetic programmes conferring floral meristem identity and floral organ identity are conserved among all angiosperms.
Cell Wall Biosynthesis
Authors: Kumar Manoj , Turner Simon
Published: May 2015

Plant cell walls encase the plant cells and provide many structural and functional roles. Cell walls are complex structures consisting mainly of polysaccharides (cellulose, hemicellulose and pectin), glycoproteins and phenolic compounds (lignin). Most plant cell wall polymers are synthesised from ‘activated’ precursors by the action of transferases. Cellulose is synthesised at the plasma membrane (PM) by a large complex moving in the plane of PM and extruding cellulose chains into the wall. The hemicelluloses are synthesised in the endomembrane system by resident glycosyl transferase enzymes and transported to the wall. These individual components are then cross‐linked and assembled into the complex matrix structure that comprises functional cell walls. Woody cell walls also contain lignin. Lignin is synthesised in the wall by oxidative coupling of individual monomeric subunits.

Key Concepts

All plant cells are encased in a multilayered cell wall.

Plant cell walls are an important renewable resource.

Plant cell walls are composed of polysaccharides (cellulose, hemicellulose and pectin), cell wall proteins and phenolic compounds.

Most of the polysaccharides are synthesised from activated precursors, NDP sugars and incorporated into the growing polymer catalysed by the action of glycosyl transferases (GTs).

Cellulose is synthesised by the cellulose synthase complex (CSC) moving in the plane of plasma membrane, extruding cellulose chains into the cell wall.

Hemi‐celluloses and pectin are synthesised and modified in the endomembrane system before being deposited into the apoplast for assembly into the cell wall.

Lignin monomers are synthesised in the cytoplasm and transported to the wall.

Laccases have an essential role in lignin formation by catalysing the oxidative coupling of the lignin monomers in the apoplast.

Cell wall composition varies greatly between cell types and can change as the cell differentiates and with the developmental stages of cells and the plant.

The cell wall has an important function in regulating how plant cells achieve their final size and shape and consequently have an essential role in regulating plant growth.
Collective Cell Migration in Tissue Building
Authors: Muñoz‐Soriano Verónica , Paricio Nuria
Published: May 2015

Collective cell migration (CCM) is an essential process during tissue building and morphogenesis of animal body plans, but it can also occur in pathogenic situations. A detailed study of this cell behaviour in several model systems has allowed to determine that cells move coordinately but interact differently while migrating together, thus defining several categories of collective cell movements. They are regulated by guidance signals that act as chemoattractants and allow directionality of movement and whose levels, together with the action of repulsive molecular cues, influence this movement. Besides, cells in the moving group affect each other through cell–cell interactions but they also interplay with the environment. Here, we describe the specific features of CCM and its different manifestations
in vivo
. We also discuss the potential relevance of the results obtained in the study of this cell behaviour in deciphering the molecular and cellular mechanisms underlying tumour invasion and metastasis.

Key Concepts

Cells can move either individually or collectivelly.

Collective cell migration occurs during morphogenesis of animal body plans.

Abnormal collective migration underlies pathological states such as tumour cell invasion and metastasis.

During collective cell migration, groups of cells move together directionally and in a coordinated manner.

Collective cell movements are regulated by dynamic gradients of extracellular signalling molecules, environmental geometrical constraints and intercellular communication.

Different types of collective cell movements have been defined according to the interactions among the cells in the moving cluster.

The use of
in vitro
,
in vivo
and theoretical models is contributing to understand how collective cell migration occurs.
Culture and Social Networks
Authors: Fuhse Jan A.
Published: May 2015

Since the early 1990s, social networks and culture are increasingly seen as intertwined and studied in conjunction. This “cultural turn” of network research is based on the relational sociology of Harrison White and others. It links classical structuralism with cultural analysis. Three approaches to the linkage of culture and social networks can be distinguished: The first traces cultural developments, for example, in science or in art, to network constellations: collective identities arise out of densely connected networks; new styles emerge at the intersection of network clusters from the combination of previously unconnected repertoires. The second approach views social networks themselves as intricately interwoven with culture. Roles in a network (e.g., kinship roles) are built on culturally available blueprints (institutions). As are relationships that varyingly adopt relationship frames such as “love” or “patronage.” Styles and collective identities develop from network constellations and shape them in turn. The third approach analyzes culture itself as a network of symbols and concepts. Their meaning lies in the relations to other concepts and symbols. Network analyses of culture have frequently analyzed the meaning of role categories and of relationship frames, thus linking the three approaches. Areas of particular interest for going forward include research on micro‐events in networks, the interplay of networks with ethnic categories and cultural differences, and the role of networks in societal fields.
Evolutionary Perspectives on Animal and Human Personality
Authors: Manson Joseph H. , Fairbanks Lynn A.
Published: May 2015

Among many nonhuman animals, individuals differ consistently in their response tendencies (e.g., shy vs bold) across multiple contexts. Researchers have tested evolutionary hypotheses accounting for these phenomena, and have also begun exploring evolutionary explanations for human personality variation. For evolutionary biologists, a trait's significance lies in its effects on
fitness
, that is, the lifetime reproductive success of individuals who bear the trait, including indirect effects through the reproductive success of genetic relatives. Recent evolutionary personality research has pursued several alternative theoretical lines of inquiry:
balancing selection
models explore whether optimal levels of personality traits vary across time, space, or trait frequency distribution;
mutation‐selection balance
models propose that selection for a single optimum personality configuration is undermined by mutations at multiple genetic loci; and
facultative calibration models
hold that personality trait levels are adjusted, during individual development, to other characteristics that affect social bargaining power. A promising general approach links personality variation to variation in life history strategy, that is, the allocation of effort among the competing demands of growth, somatic maintenance, mate acquisition, and parental investment. Emerging areas of research include relationships between personality variation and biological fitness in humans and other primates; the extent to which personality trait levels are adjusted based on individual condition; the degree to which situational flexibility varies among individuals; and whether proposed structural models of personality, such as the human five‐factor model (extraversion, neuroticism, agreeableness, conscientiousness, and openness to experience) are species‐typical or are affected by variable ecological and social conditions.
Global Income Inequality
Authors: Firebaugh Glenn
Published: May 2015

This essay describes the evolution of global income inequality over the past two‐and‐a‐half centuries, and its likely evolution during the twenty‐first century. Global income inequality—the sum of inequality within and between nations—is massive today, the legacy of uneven growth in the world's regions since the advent of the Industrial Revolution. Because incomes shot up in the West while lagging behind in Asia and Africa over most of this period, between‐nation income inequality grew dramatically, and most global income inequality now lies between nations. Economic growth remains uneven across the world's regions, but the fastest growth is occurring in populous poor regions of the world, compressing between‐nation inequality. As a result, global income inequality is currently receding, according to most (but not all) investigations of the matter. The compression of global inequality is attributable to rapid economic growth in China and India: If the rate of economic growth in China and India were the same as in the rest of the world, global income inequality would not be declining. The slow rate of economic growth in sub‐Saharan Africa, on the other hand, is retarding the decline. A high level of global income inequality is problematic in large part because it results in abject poverty for masses of people. If average income in the world continues to rise, alleviating abject poverty in the twenty‐first century, for future generations the level of global income inequality might matter much less than the level of income inequality within local communities.
Health and Social Inequality
Authors: Pescosolido Bernice A.
Published: May 2015

The link between social cleavages and life chances has been a mainstay of sociology, social science, and public health's contribution to understanding well‐being, morbidity, and mortality. From early classic work to the most recent studies, inequality has been associated with the incidence and prevalence of disease, access to health care, and higher‐than‐expected death rates, even for infants. Importantly, these differences have been documented for individuals, for neighborhoods, and for nations. On all of these key indicators, there is a clear gradient, whether measured by socioeconomic status (SES), education, or even social networks. Recent work has restated and expanded the impact of inequality through the Theory of Fundamental Causes and a focus on “health disparities.” The latter targets group membership by race, ethnicity, and/or gender, to name a few social characteristics. However, challenges arise from pushing our understandings of the role of inequalities further as status configurations, for example, only proxy the social interactions, social conditions, and social experiences that produce inequality. New theoretical and empirical research also suggests that incorporating biology into our understanding of how social inequality translates into poor health, unequal treatment, and premature death can be done by synthesizing new visions of sociocultural embeddedness with biological embedding into a complex systems framework for health and health care research. This integration dismisses the “old silos” and calls for increased collaborations across the sociomedical sciences, medicine, and genetics.
Implicit Attitude Measures
Authors: Mitchell Gregory , Tetlock Philip E.
Published: May 2015

Owing to concerns about the willingness and ability of people to report their attitudes accurately in response to direct inquiries, psychologists have developed a number of unobtrusive, or implicit, measures of attitudes. The most popular contemporary implicit measures equate spontaneous responses to stimuli with attitudes about those stimuli. Although these measures have been used to open important new lines of inquiry, they suffer from reliability and construct validity problems and administration limitations. Researchers conducting basic research on attitudes may fruitfully utilize implicit measures as part of a multipronged measurement strategy, but researchers seeking to predict behavior from attitudes should continue to rely on explicit measures of attitudes, taking care to minimize reactive bias and to formulate the attitude questions at the same level of specificity as the behavior to be predicted.
Leadership
Authors: Tecza Adrienne , Johnson Dominic
Published: May 2015

Historically, research on human leadership has been the sole domain of the social sciences, and has focused on the formalized role leaders have come to play in modern institutions. However, an independent yet parallel body of work has recently emerged in biology, where evolutionary theory is being used to investigate the origins and function of leader–follower dynamics in nonhuman animals. In recent years, interdisciplinary scholars in evolutionary psychology have attempted to merge these previously disparate research traditions, investigating whether the leader–follower relationships that evolved to help our species overcome challenges in the past holds insights for leadership strategies in our modern world. In this essay, we investigate the feasibility of such an interdisciplinary approach, the obstacles it faces, and the promise it holds for the future of leadership research.
Immigrant Sociocultural Adaptation, Identification, and Belonging
Authors: Mahler Sarah J.
Published: May 2015

For over 150 years and motivated by mass rural‐to‐urban migrations precipitated by industrialization, social scientists have been studying the experiences of newcomers into established sociocultural contexts. They rightly hypothesized that people's identifications with their social groups, their feelings of belonging in particular, might be altered in societies where the scope and scale of social life rapidly expanded well beyond the face‐to‐face relations characteristic of smaller‐scale societies. In addition, new forms of social solidarities and polarizations were swiftly emerging and taking hold. Early theorists faced the daunting task of not only chronicling these changes but also of theorizing in an age of newly forged and not yet sharpened social science analytical tools. Today the opposite is true; multiple models and almost innumerable publications compete to shed just a little more light on this complex social reality. Yet there is still room for innovation. Toward that goal I identify an approach meriting twenty‐first century focus: bridging heretofore separate approaches to understanding the experiences of immigrant versus native newcomers, that is, acculturation versus enculturation. Scholars of immigration have studied acculturation intensively—the processes of adapting to new cultural contexts by people who come to these contexts firmly established culturally from their homelands. Meanwhile, the same scholars almost completely ignore enculturation—the processes involved in learning culture and belonging that occupy infants and young children. Drawing upon advances in understanding the brain‐culture nexus, this essay argues that knowing more about enculturation can inform and improve understanding of acculturation. These concepts should form an analytical continuum examining how people come to identify and belong socially and how and why these shift in the course of life—particularly with migration.
Resistive Switching of a Quasi‐Homogeneous Distribution of Filaments Generated at Heat‐Treated TiO2 (110)‐Surfaces
Authors: Rogala Maciej , Bihlmayer Gustav , Speier Wolfgang , Klusek Zbigniew , Rodenbücher Christian , Szot Krzysztof
Published: May 2015

Resistive switching of thermally treated rutile single crystals with (110) orientation is studied. A heat treatment procedure is developed that involves reduction and oxidation steps and allows to induce low resistance states in switchable regions at the surface by low‐voltage electrical stimulation with the conducting tip of an atomic force microscope. This way, it is possible to electrically imprint quasi‐homogeneous switchable regions over several square micrometers. These regions are identified to consist of nanofilaments crossing the surface with a density of around 1012 cm−2, much higher in density than observed for single crystals so far. Experimental evidence is given that these nanofilaments are not related to inherent structural imperfections such as dislocations, but may originate from the linear agglomeration of oxygen vacancies as predicted by theory. Ab initio calculations and electrical simulations are performed to analyze the filamentary structures and their network in the effort to explain the observed filamentary switching of heat‐treated single‐crystalline TiO2.
Self‐Healing Actuating Adhesive Based on Polyelectrolyte Multilayers
Authors: Gu Yuanqing , Zacharia Nicole S.
Published: May 2015

Creating actuators capable of mechanical motion in response to external stimuli is a key for design and preparation of smart materials. The lifetime of such materials is limited by their eventual wear. Here, self‐healable and adhesive actuating materials are demonstrated by taking advantage of the solvent responsive of weak polyelectrolyte multilayers consisting of branched poly(ethylenimine)/poly(acrylic acid) (BPEI/PAA). BPEI/PAA multilayers are dehydrated and contract upon contact with organic solvent and become sticky when wetted with water. By constructing an asymmetric heterostructure consisting of a responsive BPEI/PAA multilayer block and a nonresponsive component through either layer‐by‐layer assembly or the paste‐to‐curl process, smart films that actuate upon exposure to alcohol are realized. The curl degree, defined as degrees from horizontal that the actuated material reaches, can be as high as ≈228.9°. With evaporation of the ethanol, the curled film returns to its initial state, and water triggers fast self‐healing extends the actuator's lifetime. Meanwhile, the adhesive nature of the wet material allows it to be attached to various substrates for possible combination with hydrophobic functional surfaces and/or applications in biological environments. This self‐healable adhesive for controlled fast actuation represents a considerable advance in polyelectrolyte multilayers for design and fabrication of robust smart advanced materials.
Metal‐Phosphide‐Containing Porous Carbons Derived from an Ionic‐Polymer Framework and Applied as Highly Efficient Electrochemical Catalysts for Water Splitting
Authors: Han Sheng , Feng Yunlong , Zhang Fan , Yang Chongqing , Yao Zhaoquan , Zhao Wuxue , Qiu Feng , Yang Lingyun , Yao Yefeng , Zhuang Xiaodong , Feng Xinliang
Published: May 2015

A novel phosphorus‐containing porous polymer is efficiently prepared from tris(4‐vinylphenyl)phosphane by radical polymerization, and it can be easily ionized to form an ionic porous polymer after treatment with hydrogen iodide. Upon ionic exchange, transition‐metal‐containing anions, such as tetrathiomolybdate (MoS4
2−) and hexacyanoferrate (Fe(CN)6
3−), are successfully loaded into the framework of the porous polymer to replace the original iodide anions, resulting in a polymer framework containing complex anions (termed HT‐Met, where Met = Mo or Fe). After pyrolysis under a hydrogen atmosphere, the HT‐Met materials are efficiently converted at a large scale to metal‐phosphide‐containing porous carbons (denoted as MetP@PC, where again Met = Mo or Fe). This approach provides a convenient pathway to the controlled preparation of metal‐phosphide‐loaded porous carbon composites. The MetP@PC composites exhibit superior electrocatalytic activity for the hydrogen evolution reaction (HER) under acidic conditions. In particular, MoP@PC with a low loading of 0.24 mg cm−2 (on a glass carbon electrode) affords an iR‐corrected (where i is current and R is resistance) current density of up to 10 mA cm−2 at 51 mV versus the reversible hydrogen electrode and a very low Tafel slope of 45 mV dec−1, in rotating disk measurements under saturated N2 conditions.
Laccase‐Catalyzed Dimerization of Piceid, a Resveratrol Glucoside, and its Further Enzymatic Elaboration
Authors: Gavezzotti Paolo , Bertacchi Federica , Fronza Giovanni , Křen Vladimír , Monti Daniela , Riva Sergio
Published: May 2015

The laccase‐catalyzed oxidation of piceid, the 3‐β‐D‐glucopyranosyl derivative of the stilbenic phytoalexin resveratrol, allowed isolation of the corresponding β‐5 like trans‐dehydrodimer in good yield (45%) avoiding chromatography. This compound was then submitted to the action of a small library of commercially available hydrolases. While the cellulase from Trichoderma viride was able to fully hydrolyze the diglycosylated dimer to give the corresponding β‐5 like trans‐dehydrodimer of resveratrol, the β‐glucosidase from almonds allowed the isolation of a monoglycosylated intermediate in reasonable yield. The diastereoisomers and the enantiomers of the isolated dimeric products were separated using a semi‐preparative chiral column. The basic antioxidant properties of these new dimers have been determined.

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Designer Microorganisms for Optimized Redox Cascade Reactions – Challenges and Future Perspectives
Authors: Bayer Thomas , Milker Sofia , Wiesinger Thomas , Rudroff Florian , Mihovilovic Marko. D.
Published: May 2015

An immense number of chemical reactions are carried out simultaneously in living cells. Nature’s optimization approach encompasses the assembly of reactions in cascades and to embed them in finely tuned metabolic networks. With the vast progress in the field of biocatalysis, man‐made cascades, especially redox cascades, have reached a degree of complexity that needs tools for improved control and optimization. Combined strategies from biocatalysis, metabolic engineering and synthetic biology lead to the establishment of artificial metabolic pathways with minimized interference with the cellular host environment. This review will focus on genetic and metabolic engineering tools for the assembly and introduction of de novo redox pathways into the host Escherichia coli and will present state of the art redox cascades performed by tailor‐made microbial cell factories.

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Prospective of Semiconductor Memory Devices: from Memory System to Materials
Authors: Hwang Cheol Seong
Published: May 2015

The ever‐increasing demand for higher‐capacity digital memory shows no sign of declining. The conventional strategy for meeting such demand, i.e. shrinking of the memory cell size, will no longer be useful at some point in the future, owing to economic reasons and performance degradation. Nevertheless, performance of computing systems will keep improving for the next generation information technology. This indicates the necessity to consider a fundamentally disparate approach to enhance memory technology. Here, the current status of computer memory chips is reviewed and the pros and cons of the present technology are discussed from computing system, fabrication technology, and materials points of view. Based on this knowledge, the limitations of the present technologies are described, and the possible solutions suggested up to now are reassessed. Finally, a shift in the fundamental computational paradigm from von Neumann computing to other alternatives such as neuromorphic computing and material implication, is commented upon.
In Situ Synthesis of a Hierarchical All‐Solid‐State Electrolyte Based on Nitrile Materials for High‐Performance Lithium‐Ion Batteries
Authors: Zhou Dong , He Yan‐Bing , Liu Ruliang , Liu Ming , Du Hongda , Li Baohua , Cai Qiang , Yang Quan‐Hong , Kang Feiyu
Published: May 2015

A hierarchical all‐solid‐state electrolyte based on nitrile materials (SEN) is prepared via in situ synthesis method. This hierarchical structure is fabricated by in situ polymerizing the cyanoethyl polyvinyl alcohol (PVA‐CN) in succinonitrile (SN)‐based solid electrolyte that is filled in the network of polyacrylonitrile (PAN)‐based electrospun fiber membrane. The crosslinked PVA‐CN polymer framework is uniformly dispersed in the SN‐based solid electrolyte, which can strongly enhance its mechanical strength and keeps it in a quasi‐solid state even over the melting point. The electrospun fiber membrane efficiently reduces the thickness of SEN film besides a further improvement in strength. Because of the unique hierarchical structure and structure similarity among the raw materials, the prepared SEN film exhibits high room‐temperature ionic conductance (0.30 S), high lithium ion transference number (0.57), favorable mechanical strength (15.31 MPa), excellent safety, and good flexibility. Furthermore, the in situ synthesis ensures an excellent adhesion between SEN and electrodes, which leads to an outstanding electrochemical performance for the assembled LiFePO4/SEN/Li cells. Both the superior performance of SEN and the simple fabricating process of SEN‐based all‐solid‐state cells make it potentially as one of the most promising electrolyte materials for next generation lithium‐ion batteries.
The geographic distribution of genetic diversity within gorillas
Authors: Fünfstück Tillmann , Vigilant Linda
Published: May 2015

Gorillas, like all non‐human great apes, are endangered. Understanding the distribution of genetic diversity across their range is important because low diversity may arise in small populations through increased inbreeding, and, by reducing reproductive fitness, may lead to decreased chances of persistence of a given population. Previous studies found higher genetic diversity in the western (Gorilla gorilla) than in the eastern gorillas (Gorilla beringei), but rarely employed individuals of known geographic origin to investigate the distribution of diversity across multiple populations. The present study fills that gap by analyzing 1,161 individuals from nine sites across all four currently recognizedGorillasubspecies. Genetic diversity at each site was estimated using published data from seven highly‐variable microsatellite loci. We found that the small and fragmented populations of Cross River gorillas, eastern lowland gorillas and mountain gorillas were less diverse than any of the five analyzed western lowland gorilla populations. The higher levels of genetic variation within the western lowland gorillas might be best explained by the facts that they (i) exhibit larger present and past effective population sizes than the other subspecies and (ii) maintain higher rates of gene flow through the existence of largely continuous habitat within their range. With regard to conservation, the high genetic diversity within western lowland gorillas is encouraging and retention of dispersal corridors between already protected areas is essential. Am. J. Primatol. 77:974–985, 2015. © 2015 Wiley Periodicals, Inc.
The Significance of Ion Conduction in a Hybrid Organic–Inorganic Lead‐Iodide‐Based Perovskite Photosensitizer
Authors: Yang Tae‐Youl , Gregori Giuliano , Pellet Norman , Grätzel Michael , Maier Joachim
Published: May 2015

The success of perovskite solar cells has sparked enormous excitement in the photovoltaic community not only because of unexpectedly high efficiencies but also because of the future potential ascribed to such crystalline absorber materials. Far from being exhaustively studied in terms of solid‐state properties, these materials surprised by anomalies such as a huge apparent low‐frequency dielectric constant and pronounced hysteretic current–voltage behavior. Here we show that methylammonium (but also formamidinium) iodoplumbates are mixed conductors with a large fraction of ion conduction because of iodine ions. In particular, we measure and model the stoichiometric polarization caused by the mixed conduction and demonstrate that the above anomalies can be explained by the build‐up of stoichiometric gradients as a consequence of ion blocking interfaces. These findings provide insight into electrical charge transport in the hybrid organic–inorganic lead halide solar cells as well as into new possibilities of improving the photovoltaic performance by controlling the ionic disorder.
Poly(l‐lactic acid) with the organic nucleating agent N,N,N′‐tris(1H‐benzotriazole) trimesinic acid acethydrazide: Crystallization and melting behavior
Authors: Cai Yan‐Hua , Tang Ying , Zhao Li‐Sha
Published: May 2015

N,N,N′‐Tris(1H‐benzotriazole) trimesinic acid acethydrazide (BD) was synthesized from 1H‐benzotriazole acetohydrazide and trischloride to serve as an organic nucleating agent for the crystallization of poly(l‐lactic acid) (PLLA). First, the thermogravimetric analysis of BD exhibited a high thermal decomposition temperature; this indicated that BD maybe used as a heterogeneous nucleating agent of PLLA. Then, the effect of BD on the crystallization and melting behavior of PLLA was investigated through differential scanning calorimetry, depolarized light intensity measurements, and wide‐angle X‐ray diffraction. The appearance of a nonisothermal crystallization peak and increases in the glass‐transition temperature and the intensity of the diffraction peak suggested that the presence of BD accelerated the overall PLLA crystallization. Upon cooling at a rate of 1°C/min, the addition of just 0.5 wt % BD to PLLA increased the onset crystallization temperature from 101.4 to 111.3°C, and the nonisothermal crystallization enthalpy increased from 0.1 to 38.6 J/g. The isothermal crystallization behavior showed that the crystallization half‐time of PLLA with 0.5 wt % BD (PLLA/0.5% BD) decreased from 49.9 to 1.1 min at 105°C. However, the equilibrium melting point of PLLA/0.5% BD was lower than that of the pristine PLLA; this resulted from the increasing nucleating density of PLLA. The melting behavior of PLLA/0.5% BD further confirmed that BD improved the crystallization of PLLA, and the double‐melting peaks of PLLA/0.5% BD were assigned to melting–recrystallization. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42402.
PROTEOMIC ANALYSIS OF UBIQUITINATED PROTEINS FROM DELTAMETHRIN‐RESISTANT AND SUSCEPTIBLE STRAINS OF THE DIAMONDBACK MOTH, Plutella Xylostella L.
Authors: Cheng Luogen , Du Yaqiong , Hu Junli , Jiao Dongxu , Li Jin , Zhou Zhou , Xu Qin , Li Fengliang
Published: May 2015

Ubiquitin, a small protein consisting of 76 amino acids, acts in protein degradation, DNA repair, signal transduction, transcriptional regulation, and receptor control through endocytosis. Using proteomics, we compared the differentially ubiquitinated proteins between a deltamethrin‐resistant (DR) strain and a deltamethrin‐sensitive (DS) strain in third‐instar larvae of the diamondback moth. We used polyubiquitin affinity beads to enrich ubiquitinated proteins and then performed one‐dimensional SDS‐PAGE separation and mass spectrometric identification. In the DR strain, We found 17 proteins that were upregulated (relative to the DS strain), including carbonic anhydrase family members, ADP ribosylation factor 102F CG11027‐PA, protein kinase 61C, phospholipase A2, dihydrolipoamide dehydrogenase, tyrosine hydroxylase, and heat shock proteins, and five proteins that were downregulated in the DS strain, including carboxylesterase and DNA cytosine‐5 methyltransferase. These results were also verified by qPCR. The differentially ubiquitinated proteins/enzymes were mainly responsible for protein binding, catalytic activity, and molecular transducer activity. These results improve our understanding of the relationship between protein ubiquitination and the deltamethrin stress response.
Student performance on practical gross anatomy examinations is not affected by assessment modality
Authors: Meyer Amanda J. , Innes Stanley I. , Stomski Norman J. , Armson Anthony J.
Published: May 2015

Anatomical education is becoming modernized, not only in its teaching and learning, but also in its assessment formats. Traditional “steeplechase” examinations are being replaced with online gross anatomy examinations. The aims of this study were to: (1) determine if online anatomy practical examinations are equivalent to traditional anatomy practical examinations; and (2) to examine if students' perceptions of the online or laboratory testing environments influenced their performance on the examinations. In phase one, 10 third‐year students were interviewed to generate perception items to which five anatomy lecturers assigned content validity. In phase two, students' gross anatomical knowledge was assessed by examinations in two modes and their perceptions were examined using the devised survey instrument. Forty‐five second‐year chiropractic students voluntarily participated in Phase Two. The two randomly allocated groups completed the examinations in a sequential cross‐over manner. Student performance on the gross anatomy examination was not different between traditional “steeplechase” (mean ± standard deviation (SD): 69 ± 11%) and online (68 ± 15%) modes. The majority of students (87%) agreed that they felt comfortable using computers for gross anatomy examinations. However, fewer students found it easy to orientate images of cadaver specimens online. The majority of students (85%) agreed that they felt comfortable working with cadavers but there was less agreement on the effect of moving around the laboratory during practical examinations. This data will allow anatomists to confidently implement online assessments without fear of jeopardizing academic rigor or student performance. Anat Sci Educ 9: 111–120. © 2015 American Association of Anatomists.
Cautious Defection: Group Representatives Cooperate and Risk Less than Individuals
Authors: Atanasov Pavel , Kunreuther Howard
Published: May 2015

Individuals often make decisions that affect groups, yet the propensities of group representatives are not as well understood than those of independent decision makers or deliberating groups. We ask how responsibility for group payoffs—in the absence of group deliberation—affects the choice. The experiment utilizes the Interdependent Security Dilemma paradigm. In its deterministic version, the game is identical to a finitely repeated Prisoner's Dilemma. In the stochastic version, potential losses are larger but uncertain, occurring with a predefined probability when one or both players choose to forgo investment in protection. Participants were assigned to play either as individuals, or as representatives of three‐person groups, with each member's choices equally likely to determine the group's payoffs. In the deterministic condition, individuals were more likely to invest (cooperate) than group representatives (80% vs. 62% of rounds). In the stochastic condition, the pattern was reversed as representatives were slightly, but not significantly, more likely to invest than individuals (46% vs. 40%). The significant interaction effect suggested that group representatives were not only less cooperative but also more risk averse than individuals. A follow‐up study supported this account by showing participants who construed the invest strategy as low‐risk than those who perceived this strategy to be high risk. Overall, group representatives exhibited a tendency to act more competitively and more cautiously than individuals acting alone. Copyright © 2015 John Wiley & Sons, Ltd.
Quantification of length‐bias in screening trials with covariate‐dependent test sensitivity
Authors: Heltshe Sonya L. , Kafadar Karen , Prorok Philip C.
Published: May 2015

Length‐biased sampling exists in screening programs where longer duration disease is detected during the preclinical stage because a longer sojourn time (preclinical duration) has a higher probability of being screen detected. By modeling the course of disease, we quantify the effect of length‐biased sampling on clinical duration when cases are subject to periodic screening with variable test sensitivity. We use the highly flexible bivariate lognormal density to jointly model preclinical and clinical durations, and we model screening test sensitivity as a function of the sojourn time and number of previous false negative screens. We show that the mean clinical duration among screen‐detected cases can be up to 40% higher, with shrinking standard deviation, than those among nonscreen‐detected cases, due to biased sampling alone, irrespective of any possible benefit (increased survival time arising from earlier detection or reduction in mortality). These findings will aid in the design and interpretation of screening trials.
In vitro generation of functional dendritic cells differentiated from CD34 negative cells isolated from human umbilical cord blood
Authors: Park Yo Seph , Shin Changsik , Hwang Han Sung , Zenke Martin , Han Dong Wook , Kang Young Sun , Ko Kisung , Do Yoonkyung , Ko Kinarm
Published: May 2015

Dendritic cells (DCs) are the most potent antigen‐presenting cells that play a crucial role in the initiation of an immune response. As DC‐based therapeutic applications is increasing, large‐scale DC production is required for transplantation. Human umbilical cord blood (UCB) has been shown to contain a rare and precious population of hematopoietic stem cells (HSCs), which can give rise to DCs. The CD34 antigen has been widely used as a cell surface marker to identify HSCs. In this study, we used CD34 antibody to isolate CD34+ and CD34− cells and compared the ability to differentiate into DCs. We used a two‐step method combined with the magnetic bead sorting system to isolate CD34+ and CD34− cells from human UCB. Analysis of cellular properties and functionality using a migration assay and T cell proliferation assay revealed no significant differences between CD34+ cells and CD34− cells in their ability to generate DCs.
Management for traumatic chronic subdural hematoma patients with well‐controlled shunt system for hydrocephalus
Authors: Yamada Shoko Mitrrt , Tomia Yusuke , Murakami Hideki , Nakane Makoto
Published: May 2015

Key Clinical Message

Traumatic CSDH enlarged in two cases with VP or LP shunt system although the shunt valve pressure was increased to 200 mmH2O. In surgery, the hematoma cavity pressure was found to be 130 and 140 mmH2O, suggesting that to raise the shunt valve pressure is not effective for decreasing CSDH volume.
Tracking Non‐Uniform Mesoscale Transport in LiFePO4 Agglomerates During Electrochemical Cycling
Authors: Nelson Weker Johanna , Li Yiyang , Shanmugam Rengarajan , Lai Wei , Chueh William C.
Published: May 2015

State‐of‐charge maps of a LiFePO4 electrode in standard nonaqueous electrolyte are recorded in operando with a resolution of tens of nanometers by using hard X‐ray spectroscopic microscopy. We observe spatially inhomogeneous charging and discharging of the composite electrode, with predominately Li‐rich and Li‐poor micron‐scale agglomerates. There appears to be no correlation between the agglomerate size and the (de)lithiation pathway. Additionally, we observe that the electrochemical heterogeneity exhibits a “last to delithiate, first to lithiate” behavior, in which the regions that are the last to charge are also the regions that are the first to discharge. These observations suggest that the nanoscale pore structure within the agglomerates dominates lithium‐ion transport.
On the Extreme Oxidation States of Iridium
Authors: Pyykkö Pekka , Xu Wen‐Hua
Published: May 2015

It has recently been suggested that the oxidation states of Ir run from the putative −III in the synthesized solid Na3[Ir(CO)3] to the well‐documented +IX in the species IrO4+. Furthermore, [Ir(CO)3]3−was identified as an 18‐electron species. A closer DFT study now finds support for this picture: The orbitals spanned by the 6s,6p,5d orbitals of the iridium are all occupied. Although some have considerable ligand character, the deviations from 18 e leave the orbital symmetries unchanged. The isoelectronic systems from Os−IVto Au−Ibehave similarly, suggesting further possible species. To paraphrase Richard P. Feynmann “there is plenty of room at the bottom”.
Experimental and Theoretical Investigations of the Stereoselective Synthesis of P‐Stereogenic Phosphine Oxides
Authors: Copey Laurent , Jean‐Gérard Ludivine , Framery Eric , Pilet Guillaume , Robert Vincent , Andrioletti Bruno
Published: May 2015

An efficient enantioselective strategy for the synthesis of variously substituted phosphine oxides has been developed, incorporating the use of (1S,2S)‐2‐aminocyclohexanol as the chiral auxiliary. The method relies on three key steps: 1) Highly diastereoselective formation of PV oxazaphospholidine, rationalized by a theoretical study; 2) highly diastereoselective ring‐opening of the oxazaphospholidine oxide with organometallic reagents that takes place with inversion of configuration at the P atom; 3) enantioselective synthesis of phosphine oxides by cleavage of the remaining PO bond. Interestingly, the use of a PIII phosphine precursor afforded a P‐epimer oxazaphospholidine. Hence, the two enantiomeric phosphine oxides can be synthesized starting from either a PV or a PIII phosphine precursor, which constitutes a clear advantage for the stereoselective synthesis of sterically hindered phosphine oxides.
ChemInform Abstract: Chemical and Structural Evolution in the Th—SeO32‐/SeO42‐System: From Simple Selenites to Cluster‐Based Selenate Compounds.
Authors: Xiao Bin , Langer Eike , Dellen Jakob , Schlenz Hartmut , Bosbach Dirk , Suleimanov Evgeny V. , Alekseev Evgeny V.
Published: May 2015

Single crystals of α‐Th(SeO3)2 (I) and β‐Th(SeO3)2 (II) are grown under hydrothermal conditions using Th(NO3)4, SeO2, and NaNO3 (for intentional Na‐containing compounds) in molar ratios of 1:3:5 and 1:1:3, resp.
ChemInform Abstract: The Mercury‐Richest Europium Amalgam Eu10Hg55.
Authors: Tambornino Frank , Hoch Constantin
Published: May 2015

Single crystals of Eu10Hg55 are prepared by isothermal electrocrystallization under anhydrous conditions from a solution of EuI3·8DMF in DMF on a reactive Hg cathode (amalgamated Cu spoon, 5 V, 72 h).
ChemInform Abstract: Many Metals Make the Cut: Quaternary Rare‐Earth Germanides RE4M2InGe4 (M: Fe, Co, Ni, Ru, Rh, Ir) and RE4RhInGe4 Derived from Excision of Slabs in RE2InGe2.
Authors: Oliynyk Anton O. , Stoyko Stanislav S. , Mar Arthur
Published: May 2015

Arc‐melting and annealing of the elements (evacuated silica tubes, 800 °C, 1 week) is used to prepare ≈50 new quaternary germanides of the series Ln4M2InGe4 (Ln: Ce—Lu except Eu and Yb; M: Fe, Co, Ni, Ru, Rh, Ir) and a different but closely related series Ln4RhInGe4.
ChemInform Abstract: Asymmetric Phase‐Transfer Catalysts Bearing Multiple Hydrogen‐Bonding Donors: Highly Efficient Catalysts for Enantio‐ and Diastereoselective Nitro‐Mannich Reaction of Amidosulfones.
Authors: Wang Bin , Liu Yuxin , Sun Cong , Wei Zhonglin , Cao Jungang , Liang Dapeng , Lin Yingjie , Duan Haifeng
Published: May 2015

A new class of bifunctional phase‐transfer catalysts derived from cinchona alkaloids and various β‐amino alcohols are prepared and applied in the title reaction.
ChemInform Abstract: Investigation of the Diastereoselective Mannich Reaction Using Imidazolidin‐2‐thione as a Chiral Auxiliary.
Authors: Zhu Liang , Lu Cuifen , Chen Zuxing , Yang Guichun , Li Yan , Nie Junqi
Published: May 2015

The strong Lewis acid TiCl4 is employed in the anti‐selective Mannich reaction of aromatic aldimines with aliphatic imidazolidin‐2‐thiones.