bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebral Cortex
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

The cerebrum is divided into four lobes: frontal, parietal, occipital, and temporal and into two gyri: the cingulate and insular. The four lobes were named based on their relationship to the overlying skull bones. There is a left and right hemisphere and each of these lobes has a distinct function. The major cell types in the cerebrum consist of two types—spiny or nonspiny stellate and pyramidal cell. The cortex of the cerebrum is laminated and is divided into six layers: layer 1, molecular or plexiform; layer Ii, external granular; layer iii, external pyramidal; layer iv, internal granular; layer v, internal or large and giant pyramidal cell layers; and layer vi, multiform or fusiform and spindle cell layer. Callosal fibers originate from the external three layers; all layers form associational fibers; the major thalamic input is into layer iv or i. The major output from the cerebrum onto subcortical regions is from layer v for brain stem and spinal cord and Brodmann divided the cerebral cortex into 52 different areas based on the differences noted in the lamination of the cortical layers.
Motor System and Movement
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

There are central pattern generators that initiate movements in the spinal cord and mesencephalon. In order to understand motor functions, we have listed the effects of transection of the spinal cord compared to decerebrate and decorticate lesions. The cerebral cortex forms the optical righting. The motor cortex is area 4 in the precentral gyrus of the frontal lobe. The pyramidal tract, corticospinal pathway, originates in the motor sensory cortex and over 90% of the fibers cross over to the other side. The premotor and supplemental motor areas in the frontal lobe prepare and sequence the motor functions that permit fine movements of the limbs and vocal cords that are controlled by the motor cortex.
Visual System
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

The visual system begins in the eye in the orbit and with the receptors for vision the rods and cones in the retinae with their axons ending on the ganglion cells, which form the optic nerve that exits the orbit via the optic foramen. The optic nerve undergoes a partial decussation in the optic chiasm forming the optic nerve, whose fibers terminate in the six-layered lateral geniculate nucleus of the thalamus. The crossed fibers of the optic nerve end in layers 1, 4, and 6 of the lateral geniculate, while the uncrossed fibers end in layers 2, 3, and 5. The visual radiation that originates from the lateral geniculate is so extensive that is cannot pass directly into the occipital lobe with the most dorsally placed fibers found deep in the parietal lobe and the more ventrally placed fibers actually passing forward in Myers’ loop deep in the temporal lobe on their way to the occipital lobe. The primary visual cortex, area 17, striate cortex, is found in the calcarine cortex. The visual associational areas, 18 and 19, are found on the lateral surface of the occipital lobe.
Case History Problem Solving
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

This chapter includes problem solving for cases demonstrating deficits in the cerebrum.
Case History Problem Solving
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

This chapter includes problem solving for diseases of the cerebral hemispheres with lesion diagrams and case histories.
Atlas of the Cerebrum
Authors: Marcus Elliott M. , Jacobson Stanley , Sabin Thomas D.
Published: April 2015

This chapter includes an Atlas of gross brain sections.
Probing the Properties of Dough with Low‐Intensity Ultrasound
Authors: Scanlon Martin G. , Page John H.
Published: April 2015

Ultrasonic assessments of the properties of dough have been used over the past 15–20 years to complement studies of dough properties that use other physical testing techniques. After the principles and techniques of low‐intensity ultrasound are introduced, its use as a tool for investigating the rheology and structure of dough is reviewed. One important outcome from ultrasonic assessments of dough properties is an understanding of how bubbles alter dough rheology.
Compliance with Surgical Care Improvement Project for Body Temperature Management (SCIP Inf-10) Is Associated with Improved Clinical Outcomes
Authors: Scott Andrew V. , Stonemetz Jerry L. , Wasey Jack O. , Johnson Daniel J. , Rivers Richard J. , Koch Colleen G. , Frank Steven M.
Published: April 2015

AbstractAbstract

Data from 45,304 noncardiac surgical patients at a single academic medical center found that 1,240 were noncompliant (body temperature < 36°C or no use of active warming). Noncompliant patients had an increased risk of infection, ischemic events, and mortality, supporting maintenance of normothermia as a useful perioperative quality measure.

Background:

In an effort to measure and improve the quality of perioperative care, the Surgical Care Improvement Project (SCIP) was introduced in 2003. The SCIP guidelines are evidence-based process measures designed to reduce preventable morbidity, but it remains to be determined whether SCIP-measure compliance is associated with improved outcomes.

Methods:

The authors retrospectively analyzed the electronic medical record data from 45,304 inpatients at a single institution to assess whether compliance with SCIP Inf-10 (body temperature management) was associated with a reduced incidence of morbidity and mortality. The primary outcomes were hospital-acquired infection and ischemic cardiovascular events. Secondary outcomes were mortality and hospital length of stay.

Results:

Body temperature on admission to the postoperative care unit was higher in the SCIP-compliant group (36.6° ± 0.5°C; n = 44,064) compared with the SCIP-noncompliant group (35.5° ± 0.5°C; n = 1,240) (P < 0.0001). SCIP compliance was associated with improved outcomes in both nonadjusted and risk-adjusted analyses. SCIP compliance was associated with a reduced incidence of hospital-acquired infection (3,312 [7.5%] vs.160 [12.9%] events; risk-adjusted odds ratio [OR], 0.68; 95% CI, 0.54 to 0.85), ischemic cardiovascular events (602 [1.4%] vs. 38 [3.1%] events; risk-adjusted OR, 0.60; 95% CI, 0.41 to 0.92), and mortality (617 [1.4%] vs. 60 [4.8%] events; risk-adjusted OR, 0.41; 95% CI, 0.29 to 0.58). Median (interquartile range) hospital length of stay was also decreased: 4 (2 to 8) versus 5 (2 to 14) days; P < 0.0001.

Conclusion:

Compliance with SCIP Inf-10 body temperature management guidelines during surgery is associated with improved clinical outcomes and can be used as a quality measure.
ESPGHAN and NASPGHAN Report on the Assessment of Exocrine Pancreatic Function and Pancreatitis in Children
Authors: Taylor Christopher J. , Chen Kathy , Horvath Karoly , Hughes David , Lowe Mark E. , Mehta Devendra , Orabi Abrahim I. , Screws Jeremy , Thomson Mike , Van Biervliet Stephanie , Verkade Henkjan J. , Husain Sohail Z. , Wilschanski Michael
Published: April 2015

The purpose of this clinical report is to discuss several recent advances in assessing exocrine pancreatic insufficiency (EPI) and pancreatitis in children, to review the array of pancreatic function tests, to provide an update on the inherited causes of EPI, with special emphasis on newly available genetic testing, and to review newer methods for evaluating pancreatitis.
Rational design of metal nitride redox materials for solar-driven ammonia synthesis
Authors: Michalsky Ronald , Pfromm Peter H. , Steinfeld Aldo
Published: April 2015

Fixed nitrogen is an essential chemical building block for plant and animal protein, which makes ammonia (NH
3
) a central component of synthetic fertilizer for the global production of food and biofuels. A global project on artificial photosynthesis may foster the development of production technologies for renewable NH
3
fertilizer, hydrogen carrier and combustion fuel. This article presents an alternative path for the production of NH
3
from nitrogen, water and solar energy. The process is based on a thermochemical redox cycle driven by concentrated solar process heat at 700–1200°C that yields NH
3
via the oxidation of a metal nitride with water. The metal nitride is recycled via solar-driven reduction of the oxidized redox material with nitrogen at atmospheric pressure. We employ electronic structure theory for the rational high-throughput design of novel metal nitride redox materials and to show how transition-metal doping controls the formation and consumption of nitrogen vacancies in metal nitrides. We confirm experimentally that iron doping of manganese nitride increases the concentration of nitrogen vacancies compared with no doping. The experiments are rationalized through the average energy of the dopant d-states, a descriptor for the theory-based design of advanced metal nitride redox materials to produce sustainable solar thermochemical ammonia.
The social acceptance of artificial photosynthesis: towards a conceptual framework
Authors: Sovacool Benjamin K. , Gross Allan
Published: April 2015

Advancements in artificial photosynthesis have the potential to radically transform how societies convert and use energy. Their successful development, however, hinges not only on technical breakthroughs, but also acceptance and adoption by energy users. This article introduces a conceptual framework enabling analysts, planners and even investors to determine environments where artificial photosynthesis may thrive, and those where it may struggle. Drawn from work looking at the barriers and acceptance of solar photovoltaic and wind energy systems, the article proposes that social acceptance has multiple dimensions—socio-political, community and market—that must be met holistically in order for investors and users to embrace new technologies. The article argues that any future market acceptance for artificial photosynthesis will depend upon the prevalence of nine factors, which create conducive environments; the lack of the conditions engenders environments where they will likely be rejected. The conditions are (i) strong institutional capacity; (ii) political commitment; (iii) favourable legal and regulatory frameworks; (iv) competitive installation and/or production costs; (v) mechanisms for information and feedback; (vi) access to financing; (vii) prolific community and/or individual ownership and use; (viii) participatory project siting; and (ix) recognition of externalities or positive public image.
Biosolar cells: global artificial photosynthesis needs responsive matrices with quantum coherent kinetic control for high yield
Authors: Purchase R. L. , de Groot H. J. M.
Published: April 2015

This contribution discusses why we should consider developing artificial photosynthesis with the tandem approach followed by the Dutch BioSolar Cells consortium, a current operational paradigm for a global artificial photosynthesis project. We weigh the advantages and disadvantages of a tandem converter against other approaches, including biomass. Owing to the low density of solar energy per unit area, artificial photosynthetic systems must operate at high efficiency to minimize the land (or sea) area required. In particular, tandem converters are a much better option than biomass for densely populated countries and use two photons per electron extracted from water as the raw material into chemical conversion to hydrogen, or carbon-based fuel when CO
2
is also used. For the average total light sum of 40 mol m
−2
d
−1
for The Netherlands, the upper limits are many tons of hydrogen or carbon-based fuel per hectare per year. A principal challenge is to forge materials for quantitative conversion of photons to chemical products within the physical limitation of an internal potential of
ca
2.9 V. When going from electric charge in the tandem to hydrogen and back to electricity, only the energy equivalent to 1.23 V can be stored in the fuel and regained. A critical step is then to learn from nature how to use the remaining difference of
ca
1.7 V effectively by triple use of one overpotential for preventing recombination, kinetic stabilization of catalytic intermediates and finally generating targeted heat for the release of oxygen. Probably the only way to achieve this is by using bioinspired responsive matrices that have quantum–classical pathways for a coherent conversion of photons to fuels, similar to what has been achieved by natural selection in evolution. In appendix A for the expert, we derive a propagator that describes how catalytic reactions can proceed coherently by a convergence of time scales of quantum electron dynamics and classical nuclear dynamics. We propose that synergy gains by such processes form a basis for further progress towards high efficiency and yield for a global project on artificial photosynthesis. Finally, we look at artificial photosynthesis research in The Netherlands and use this as an example of how an interdisciplinary approach is beneficial to artificial photosynthesis research. We conclude with some of the potential societal consequences of a large-scale roll out of artificial photosynthesis.
Does the world need a global project on artificial photosynthesis?
Authors: Faunce Thomas
Published: April 2015

This paper introduces a theme issue ofInterface Focusderived from papers presented at the Royal Society supported meeting ‘Do we need a global project on artificial photosynthesis?’ held at Chicheley Hall in July 2014. At that meeting, leaders of national solar fuels and chemicals projects and research presented ‘state of the art’ on artificial photosynthesis (AP) in the context of the policy challenges for globalizing a practical technology to address climate change and energy and food security concerns. The discussions included contributions from many experts with legal and policy skills and uniquely focused on producing principles for prioritizing and specializing work while enhancing the funding and attendant public policy profile. To this end, representatives of major public, philanthropic and private potential stakeholders in such a project (such as the Wellcome Trust, the Moore Foundation, Shell, the Leighty Foundation, the EPSRC and Deutsche Alternative Asset Management) were invited to provide feedback at various points in the meeting. For thisInterface Focusissue, speakers at the Chicheley Hall meeting were required to present a snapshot of their cutting edge research related to AP and then draw upon the Chicheley Hall discussions to innovatively analyse how their research could best be advanced by a global AP project. Such multidisciplinary policy analysis was not a skill many of these researchers were experienced or trained in. Nonetheless their efforts here represent one of the first published collections to attempt such a significant task. This introduction contains a brief summary of those papers, focusing particularly on their policy aspects. It then summarizes the core discussions that took place at the Chicheley Hall meeting and sets out some of the central ethical principles that were considered during those discussions.
Alkalimicrobium pacificum gen. nov., sp. nov., a marine bacterium in the family Rhodobacteraceae
Authors: Zhang Gaiyun , Yang Yanliu , Wang Shuang , Sun Zhilei , Jiao Kailin
Published: April 2015

A Gram-stain-negative, aerobic, non-motile, rod-shaped bacterium, designated strain F15T, was isolated from a deep-sea sediment of the western Pacific Ocean. The temperature, pH and NaCl ranges for growth were 4–50 °C, pH 6–11 and 0–10 % (w/v), respectively. Strain F15Tshowed the highest 16S rRNA gene sequence similarity toSagittula stellataE-37T(96.4 %), followed byPonticoccus litoralisCL-GR66T(96.4 %),Antarctobacter heliothermusEL-219T(96.3 %) andThalassococcus lentusYCS-24T(96.0 %). Phylogenetic analysis based on 16S rRNA gene sequence data showed that strain F15Tformed a lineage within the familyRhodobacteraceaeof the classAlphaproteobacteria. The polar lipid profile of strain F15Tcomprised significant amounts of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one unidentified glycolipid and one unidentified phospholipid. The predominant cellular fatty acids were summed feature 8 (C18 : 1ω7cand/or C18 : 1ω6c, 40.2 %), anteiso-C15 : 0(30.4 %) and anteiso-C17 : 0(9.7 %). The genomic DNA G+C content of strain F15Twas 60.2 mol% and the major respiratory quinone was Q-10. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain F15Tis considered to represent a novel species of a new genus within the familyRhodobacteraceae, for which the nameAlkalimicrobium pacificumgen. nov., sp. nov. is proposed. The type strain is F15T( = LMG 28107T = JCM 19851T = CGMCC 1.12763T = MCCC 1A09948T).
Site-specific amino-acid preferences are mostly conserved in two closely related protein homologs
Authors: Doud Michael B. , Ashenberg Orr , Bloom Jesse D.
Published: April 2015

Evolution drives changes in a protein’s sequence over time. The extent to which these changes in sequence lead to shifts in the underlying preference for each amino acid at each site is an important question with implications for comparative sequence-analysis methods such as molecular phylogenetics. To quantify the extent that site-specific amino-acid preferences shift during evolution, we performed deep mutational scanning on two homologs of human influenza nucleoprotein with 94% amino-acid identity. We found that only a modest fraction of sites exhibited shifts in amino-acid preferences that exceeded the noise in our experiments. Furthermore, even among sites that did exhibit detectable shifts, the magnitude tended to be small relative to differences between non-homologous proteins. Given the limited change in amino-acid preferences between these close homologs, we tested whether our measurements could inform site-specific substitution models that describe the evolution of nucleoproteins from more diverse influenza viruses. We found that site-specific evolutionary models informed by our experiments greatly outperformed non-site-specific alternatives in fitting phylogenies of nucleoproteins from human, swine, equine, and avian influenza. Combining the experimental data from both homologs improved phylogenetic fit, partly because measurements in multiple genetic contexts better captured the evolutionary average of the amino-acid preferences for sites with shifting preferences. Our results show that site-specific amino-acid preferences are sufficiently conserved that measuring mutational effects in one protein provides information that can improve quantitative evolutionary modeling of nearby homologs.
The Regime Shifts Database: A Framework for Analyzing Regime Shifts in Social-Ecological Systems
Authors: Biggs Reinette (Oonsie) , Peterson Garry , Rocha Juan Carlos
Published: April 2015

This paper presents the Regime Shifts Database (RSDB), a new online, open-access database that uses a novel consistent framework to systematically analyze regime shifts based on their impacts, key drivers, underlying feedbacks, and management options. The database currently contains 27 generic types of regime shifts, and over 300 specific case studies of a variety of regime shifts. These regime shifts occur across diverse types of systems and are driven by many different types of processes. Besides impacting provisioning and regulating services, our work shows that regime shifts substantially impact cultural and aesthetic ecosystem services. We found that social-ecological feedbacks are difficult to characterize and more work is needed to develop new tools and approaches to better understand social-ecological regime shifts. We hope that the database will stimulate further research on regime shifts and make available information that can be used in management, planning and assessment.
Systematic interaction network filtering identifies CRMP1 as a novel suppressor of huntingtin misfolding and neurotoxicity
Authors: Stroedicke Martin , Bounab Yacine , Strempel Nadine , Klockmeier Konrad , Yigit Sargon , Friedrich Ralf P. , Chaurasia Gautam , Li Shuang , Hesse Franziska , Riechers Sean-Patrick , Russ Jenny , Nicoletti Cecilia , Boeddrich Annett , Wiglenda Thomas , Haenig Christian , Schnoegl Sigrid , Fournier David , Graham Rona K. , Hayden Michael R. , Sigrist Stephan , Bates Gillian P. , Priller Josef , Andrade-Navarro Miguel A. , Futschik Matthias E. , Wanker Erich E.
Published: April 2015

Assemblies of huntingtin (HTT) fragments with expanded polyglutamine (polyQ) tracts are a pathological hallmark of Huntington's disease (HD). The molecular mechanisms by which these structures are formed and cause neuronal dysfunction and toxicity are poorly understood. Here, we utilized available gene expression data sets of selected brain regions of HD patients and controls for systematic interaction network filtering in order to predict disease-relevant, brain region-specific HTT interaction partners. Starting from a large protein–protein interaction (PPI) data set, a step-by-step computational filtering strategy facilitated the generation of a focused PPI network that directly or indirectly connects 13 proteins potentially dysregulated in HD with the disease protein HTT. This network enabled the discovery of the neuron-specific protein CRMP1 that targets aggregation-prone, N-terminal HTT fragments and suppresses their spontaneous self-assembly into proteotoxic structures in various models of HD. Experimental validation indicates that our network filtering procedure provides a simple but powerful strategy to identify disease-relevant proteins that influence misfolding and aggregation of polyQ disease proteins.
The structure of a dual-specificity tyrosine phosphorylation-regulated kinase 1A–PKC412 complex reveals disulfide-bridge formation with the anomalous catalytic loop HRD(HCD) cysteine
Authors: Alexeeva Marina , Åberg Espen , Engh Richard A. , Rothweiler Ulli
Published: April 2015

Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) is a protein kinase associated with neuronal development and brain physiology. The DYRK kinases are very unusual with respect to the sequence of the catalytic loop, in which the otherwise highly conserved arginine of the HRD motif is replaced by a cysteine. This replacement, along with the proximity of a potential disulfide-bridge partner from the activation segment, implies a potential for redox control of DYRK family activities. Here, the crystal structure of DYRK1A bound to PKC412 is reported, showing the formation of the disulfide bridge and associated conformational changes of the activation loop. The DYRK kinases represent emerging drug targets for several neurological diseases as well as cancer. The observation of distinct activation states may impact strategies for drug targeting. In addition, the characterization of PKC412 binding offers new insights for DYRK inhibitor discovery.
Appropriate zone-axis orientations for the determination of crystal polarity by convergent-beam electron diffraction
Authors: Tanaka Katsushi , Okamoto Norihiko L. , Fujio Satoshi , Sakamoto Hiroki , Inui Haruyuki
Published: April 2015

A convergent-beam electron diffraction (CBED) method is proposed for polarity determination, in which polarity is determined from the intensity asymmetry of any of the hkl–\overline h\overline k\overline l Friedel pairs appearing in a zone-axis CBED pattern with a symmetric arrangement of Bijvoet pairs of reflections. The intensity asymmetry occurs as a result of multiple scattering among Bijvoet pairs of reflections in the CBED pattern. The appropriate zone-axis orientations for polarity determination are deduced for 19 of the 25 polar point groups from symmetry considerations so as to observe Bijvoet pairs of reflections symmetrically in a single CBED pattern. These appropriate zone-axis orientations deduced for the 19 polar point groups coincide with nonpolar directions. This is because the nonpolar directions for these point groups are perpendicular to an even-fold rotation axis, which guarantees the symmetric arrangement of Bijvoet pairs of reflections with respect to the symmetry (m–m′) line in a CBED pattern taken along any of the appropriate zone-axis orientations. The m–m′ line in the CBED pattern is proved to be perpendicular to the trace of the even-fold rotation axis. On the other hand, if the nonpolar direction is either perpendicular to a mirror plane or parallel to a roto-inversion axis as in the four point groups m, 3m1, 31m, \overline 6, the nonpolar direction cannot be used as the appropriate zone-axis orientation for polarity determination because the Bijvoet pairs of reflections are not arranged symmetrically in the CBED pattern. The validity of the CBED method is confirmed both by experiment and by calculation of CBED patterns.
A look-up table based approach to characterize crystal twinning for synchrotron X-ray Laue microdiffraction scans
Authors: Li Yao , Wan Liang , Chen Kai
Published: April 2015

An automated method has been developed to characterize the type and spatial distribution of twinning in crystal orientation maps from synchrotron X-ray Laue microdiffraction results. The method relies on a look-up table approach. Taking into account the twin axis and twin plane for plausible rotation and reflection twins, respectively, and the point group symmetry operations for a specific crystal, a look-up table listing crystal-specific rotation angle–axis pairs, which reveal the orientation relationship between the twin and the parent lattice, is generated. By comparing these theoretical twin–parent orientation relationships in the look-up table with the measured misorientations, twin boundaries are mapped automatically from Laue microdiffraction raster scans with thousands of data points. Taking advantage of the high orientation resolution of the Laue microdiffraction method, this automated approach is also applicable to differentiating twinning elements among multiple twinning modes in any crystal system.
AniCryDe: calculation of elastic properties in silicon and germanium crystals
Authors: Camattari Riccardo , Lanzoni Luca , Bellucci Valerio , Guidi Vincenzo
Published: April 2015

A code to calculate the anisotropic elastic properties in a silicon or germanium crystal is introduced. The program, named AniCryDe, allows the user to select the crystallographic configuration of interest. For the selected crystallographic orientation, AniCryDe calculates several key mechanical parameters, such as Young's modulus, Poisson's ratio and the shear modulus. Furthermore, the program displays both the compliance and the stiffness tensors concerning the crystallographic orientation of interest. The code enables the user to set several parameters through a user-friendly control stage. As a result, the user obtains the complete displacement field of a deformed crystal and the curvature of any crystallographic plane. Manufacturing wafer defects such as miscut and misflat angle are also taken into account.
Influence of sample preparation on the microstructure of tooth enamel apatite
Authors: Kallistová Anna , Skála Roman , Horáček Ivan , Miyajima Nobuyoshi , Malíková Radana
Published: April 2015

X-ray powder diffraction and transmission electron microscopy are widely used for determination of the basic characteristics of the biological apatite structure. Many different techniques have been adopted for separation of the enamel part of the tooth for use in these analytical methods, but their influence on the sample itself has not yet been studied. In this paper, six different preparation techniques have been applied on pigs' teeth to see their effect on the microstructure of dental hydroxyapatite. Although the only inorganic component of the tooth is the hydroxyapatite, new phases, such as calcite, aragonite, calcium hydrogen phosphate and calcium carbonate hydroxide, appeared when a drilling technique or deproteination of the sample was used. In addition, the crystallite size (especially in the c-axis direction) varies within a wide range (330–700 Å) depending on the preparation technique. Thus, the results indicate a strong effect of the enamel separation on the phase composition and crystallite size. The method providing results most consistent with previous studies is manual disintegration.
DSR: enhanced modelling and refinement of disordered structures with SHELXL
Authors: Kratzert Daniel , Holstein Julian J. , Krossing Ingo
Published: April 2015

One of the remaining challenges in single-crystal structure refinement is the proper description of disorder in crystal structures. This paper describes a computer program that performs semi-automatic modelling of disordered moieties in SHELXL [Sheldrick (2015). Acta Cryst. C71, 3–8.]. The new program contains a database that includes molecular fragments and their corresponding stereochemical restraints, and a placement procedure to place these fragments on the desired position in the unit cell. The program is also suitable for speeding up model building of well ordered crystal structures.
Inception and movement of a `subgrain boundary precursor' in ice under an applied stress, observed by X-ray synchrotron radiation Bragg imaging
Authors: Philip A. , Capolo L. , Meyssonnier J. , Baruchel J.
Published: April 2015

Basal slip of dislocations, the easiest deformation mechanism of ice crystals, does not allow a response to any strain state. The first steps of another mechanism, with a moving subgrain boundary precursor region, which permits accommodating the effect of an applied load, is investigated on an ice single crystal, mainly using synchrotron radiation Bragg diffraction imaging. During this process, the evolution of the local integrated intensity shows that there is both a general multiplication of dislocations within the crystal and a movement of basal dislocations towards the surface. The `subgrain boundary precursor' region evolves towards a classical grain boundary when further deformed.
Determination of small crystal structures from a minimum set of diffraction intensities by homotopy continuation
Authors: Leggas Dimitri , Tsodikov Oleg V.
Published: April 2015

No deterministic approach to obtaining a crystal structure from a set of diffraction intensities exists, despite significant progress in traditional probabilistic direct methods. One of the biggest hurdles in determining a crystal structure algebraically is solving a system of many polynomial equations of high power on intensities in terms of atomic coordinates. In this study, homotopy continuation is used for exhaustive investigation of such systems and an optimized homotopy continuation method is developed with random restarts to determine small (N< 5) crystal structures from a minimum set of error-free intensities.
Icosahedral symmetry breaking: C60to C84, C108and to related nanotubes
Authors: Bodner Mark , Bourret Emmanuel , Patera Jiri , Szajewska Marzena
Published: April 2015

This paper completes the series of three independent articles [Bodneret al.(2013).Acta Cryst. A69, 583–591, (2014),PLOS ONE, 10.1371/journal.pone.0084079] describing the breaking of icosahedral symmetry to subgroups generated by reflections in three-dimensional Euclidean space {\bb R}^3 as a mechanism of generating higher fullerenes from C60. The icosahedral symmetry of C60can be seen as the junction of 17 orbits of a symmetric subgroup of order 4 of the icosahedral group of order 120. This subgroup is noted byA1×A1, because it is isomorphic to the Weyl group of the semi-simple Lie algebraA1×A1. Thirteen of theA1×A1orbits are rectangles and four are line segments. The orbits form a stack of parallel layers centered on the axis of C60passing through the centers of two opposite edges between two hexagons on the surface of C60. These two edges are the only two line segment layers to appear on the surface shell. Among the 24 convex polytopes with shell formed by hexagons and 12 pentagons, having 84 vertices [Fowler & Manolopoulos (1992).Nature (London),355, 428–430; Fowler & Manolopoulos (2007).An Atlas of Fullerenes. Dover Publications Inc.; Zhanget al. (1993).J. Chem. Phys.98, 3095–3102], there are only two that can be identified with breaking of theH3symmetry toA1×A1. The remaining ones are just convex shells formed by regular hexagons and 12 pentagons without the involvement of the icosahedral symmetry.
Crystal structure ofcatena-poly[bis[μ3-2-(2-nitrophenyl)acetato-κ3O:O:O′]disilver(I)]
Authors: Danish Muhammad , Tahir Muhammad Nawaz , Iftikhar Sana , Ahmad Nazir
Published: April 2015

The title compound, [Ag2(C8H6NO4)2]n, is a silver complex of 2-(2-nitrophenyl)acetic acid. The molecules are not conventional crystallographic inversion dimers but consist of two independent ligands and two AgIions, each with a distorted T-shaped coordination environment. The dihedral angles between acetate groups and the benzene rings are 51.1 (2) and 57.9 (2)°. The nitro groups are oriented at dihedral angles of 23.6 (5) and 32.3 (3)° with respect to the parent benzene rings. The dimers form polymeric chains along thea-axis direction. The Ag...Ag separation within a dimer is 2.8200 (5) and between symmetry-related dimers is 3.6182 (5) Å. The polymeric chains are interlinked by C—H...O hydrogen-bond interactions.
Crystal structure of bis(2-amino-5-chloropyridinium) tetrachloridocobaltate(II)
Authors: Mghandef Marwa , Boughzala Habib
Published: April 2015

The title salt, (C5H6ClN2)2[CoCl4], was synthesized by slow evaporation of an aqueous solution at room temperature. The asymmetric unit consists of two essentially planar (C5H6ClN2)+cations [maximum deviations = 0.010 (3) and 0.014 (3) Å] that are nearly perpendicular to each other [dihedral angle = 84.12 (7)°]. They are bonded through N—H...Cl hydrogen bonds to distorted [CoCl4]2−tetrahedra, leading to the formation of undulating layers parallel to (100). The structure is isotypic with the Zn analogue [Kefiet. al(2011).Acta Cryst.E67, m355–m356.]
Crystal structure ofcatena-poly[[[tetraaquazinc(II)]-μ-1,4-bis[4-(1H-imidazol-1-yl)benzoyl]piperazine] dinitrate monohydrate]
Authors: Hou Chen , Gan Hong-Mei , Liu Jia-Cheng
Published: April 2015

In the title polymeric complex, {[Zn(C24H22N6O2)(H2O)4](NO3)2·2H2O}n, the ZnIIcation, located about a twofold rotation axis, is coordinated by two imidazole groups and four water molecules in a distorted N2O4octahedral geometry; among the four coordinate water molecules, two are located on the same twofold rotation axis. The 1,4-bis[4-(1H-imidazol-1-yl)benzoyl]piperazine] ligand is centro-symmetric, with the centroid of the piperazine ring located on an inversion center, and bridges the ZnIIcations, forming polymeric chains propagating along [201]. In the crystal, O—H...O and weak C—H...O hydrogen bonds link the polymeric chains, nitrate anions and solvent water molecules into a three-dimensional supramolecular architecture. A short O...O contact of 2.823 (13) Å is observed between neighboring nitrate anions.
Crystal structure of 4′-bromo-2,3,5,6-tetrafluorobiphenyl-4-carbonitrile
Authors: Heckel Ricarda , Hulliger Jürg , Schwarzer Anke , Weber Edwin
Published: April 2015

The title compound, C13H4BrF4N, synthesized from 1,4′-bromoiodobenzene and 4-bromo-2,3,5,6-tetrafluorobenzonitrile in a coupling reaction was found to crystallize in the orthorhombic space groupP212121. The two phenyl rings are rotated with respect to each other by 40.6 (6)°. The molecules interactviaaryl–perfluoroaryl stacking [3.796 (2) and 3.773 (2) Å], resulting in intermolecular chains along thea-axis direction. C—H...F contacts of about 2.45 Å connect these chains. In contrast to the structure of the parent compound 4′-bromobiphenyl-4-carbonitrile, CN...Br contacts that could have given rise to a linear arrangement of the biphenyl molecules desirable for non-linear optical (NLO) materials are not observed in the packing. Instead, several Br...F [3.2405 (17) and 3.2777 (18) Å] and F...F [2.894 (2) Å] contacts of side-on type II form an intermolecular network of zigzag chains. The crystal studied was refined as an inversion twin.
Employee perception of diversity in Morocco: empirical insights
Authors: Hassi Abderrahman , Foutouh Najoua , Ramid Souhail
Published: April 2015

Purpose

– The present paper aims to shed light on workers ' perception of diversity and their demographical characteristics as well as characteristics of their organizations.

Design/methodology/approach

– Descriptive statistics and multiple regression technique were used to, respectively, describe the sample and test the research hypothesis.

Findings

– The current study findings reveal that three variables influence employee perception about diversity within Moroccan organizations, namely, education, industry and nationality. The more employees are educated, the more positively they perceive diversity. The same logic applies to nationality and industry. Diversity is better perceived by foreign workers in Morocco and is most prevalent in the services industry.

Research limitations/implications

– The sample size (N= 87) is too small compared to the number of variables included in the research.

Practical implications

– Enhancing employees’ diversity climate perceptions may have financial and non-financial implications for organizations. Moreover, diversity perception is linked to worker attitudes in the workplace.

Social implications

– Policymakers in Morocco ought to design and enforce human resource policies that encourage organizations to recruit employees with diverse backgrounds. To do so, it is recommended that a commission or task force be created to fulfill the role of a “watchdog” in diversity-related spheres such as developing plans and models for employers, setting diversity-related goals and objectives and putting in place adequate and effective mechanisms and tools to assess the implementation of diversity initiatives by Moroccan organizations.

Originality/value

– The current research is the first survey-based study on the topic in the Moroccan context. Further, the fact the respondents are from various organizations, industries and sectors allows for the elimination of the normative influence of a single organizational culture.
Bountiful enlightenment and transcendence
Authors: Kazanjian Christopher , Choi Su-Jin
Published: April 2015

Purpose

– The purpose of this paper is to offer educators and social workers three innovative tools to engage diverse community environments.

Design/methodology/approach

– The methodology of this paper comes from extensive research into areas of the 1950s Beat culture, humanistic psychology and Bhuddism. The literature has been synthesized to create the tools.

Findings

– The result of the literature review is three diverse yet helpful tools that educators and social workers can use for to help them serve diverse communities.

Originality/value

– This paper is significant because communities around the world are diversifying. Educators and social workers need better tools to help their methods become more effective. The authors offer these three tools as a gateway.
Resilient leadership: a transformational-transactional leadership mix
Authors: Dartey-Baah Kwasi
Published: April 2015

Purpose

– This paper aims to bring to bear the resemblance between the current resilient leadership theory and the transformational–transactional leadership theories. It does this with the view of re-focusing discussions of leadership on an effective mix of the transformational–transactional leadership theories to achieve the desired organisational performance, rather than a new look at leadership from the resilient leadership perspective – which is quite the same.

Design/methodology/approach

– It achieves this purpose by reviewing literature on the three leadership styles; and further goes on to draw a conceptual link among them to buttress the point that resilient leadership is a repetition of the ideas underlying the two already existing theories – transformational and transactional.

Findings

– A review of the three leadership theories in literature showed that qualities such as strategic thinking, emotional intelligence, adaptation/change orientation, learning, performance orientation and collective leadership as captured under the resilient leadership theory are already considered under the transformational–transactional leadership theories, and thus, constitutes a repetition not needed in the search for the best leadership approach.

Originality/value

– The current volatile, uncertain, complex and ambiguous environment calls for a new leadership thinking/approach – one that is known and empirically tested to yield best results. In this regard, the present study advocates for a consideration of the transformational–transactional approaches, which have been proven to yield best results, to focus the discussion on leadership.
How the litter‐feeding bioturbator Orchestia gammarellus promotes late‐successional saltmarsh vegetation
Authors: Schrama Maarten , van Boheemen Lotte A. , Olff Han , Berg Matty P.
Published: April 2015

Traditionally, studies on vegetation succession have focused either on plant–plant interactions or on interactions between plants and their physical environment, for example through organic matter build‐up and increased nutrient cycling. These interactions can change conditions for macrodetritivores that feed on plant litter, but their role in vegetation succession is rarely studied. In this paper, we explore whether the bioturbating crustacean macrodetritivore Orchestia gammarellus alters soil conditions in a saltmarsh ecosystem in such a way that it promotes late‐successional, less stress‐tolerant plant species at the expense of early successional species.

To answer this, we performed a field and a laboratory experiment in which we manipulated abundances of O. gammarellus, and studied the consequences for soil physical and chemical parameters and for vegetation community composition.

Our field experiment showed that O. gammarellus stimulated nitrogen mineralization, likely resulting from the positive effect of this macrodetritivore on soil aeration and litter decomposition. Moreover, results from the laboratory experiment showed that O. gammarellus negatively affected dicot seedling survival of mainly early successional plant species, likely through grazing, thus affecting plant community composition.

The experiments together provided evidence that O. gammarellus promotes late‐successional plant species in multiple ways: by alleviation of anoxic conditions, by promoting nutrient cycling and by selective herbivory on early successional species.

Synthesis. By demonstrating that a species traditionally considered as part of the detrital (‘brown’) food web is thus an important accelerator of vegetation succession, this study documents an important but often overlooked link in food web and ecosystem ecology.
The Open‐Economy Trilemma in China: Monetary and Exchange‐Rate Policy Interaction under Financial Repression
Authors: Wu Ying
Published: April 2015

This paper models China's monetary‐cum‐exchange rate policy, in which sterilization measures insulate base money from the full effects of capital inflow while the accumulation of net foreign assets (NFAs) limits exchange‐rate appreciation. I find that the negative‐risk premium in the interest rate—which compensates NFA holders for exchange‐rate risk with a higher relative rate of return on their NFAs—plays a pivotal role in influencing the magnitude of sterilization and in inducing endogenous change in the exchange rate. I show that a feedback loop between the exchange rate and capital inflow exists in the form of a multiplier mechanism that jeopardizes both monetary autonomy and exchange‐rate stability. The findings testify to the open‐economy trilemma challenging the effectiveness and sustainability of China's monetary‐cum‐exchange rate policy and point to a flexible exchange rate as a solution that can enhance monetary sovereignty, reduce financial repression and improve economic efficiency.
Asymmetric Information, Externalities and Incentives in Animal Disease Prevention and Control
Authors: Hennessy David A. , Wolf Christopher A.
Published: April 2015

Incentives influence behaviour while an understanding of farmer behaviour facilitates the control and prevention of infectious livestock disease. This paper lays out several perspectives on how information problems and other externalities affect biosecurity incentives. We use the principal–agent framework to examine livestock disease management in the presence of potential moral hazard and adverse selection. Moral hazard may apply to biosecurity decisions while adverse selection may apply to disease reporting. The example of compensation policies illustrates the importance of creating appropriate incentives: compensation must be sufficient to ensure early reporting but not so large as to discourage appropriate levels of biosecurity effort. Other cases of externalities are more diffuse than those modelled using principal–agent analysis, placing emphasis on third‐party effects and coordination problems. Three examples are provided. One concerns free‐riding when facing an endemic disease pool that can be managed by limiting sources and flows. Another regards coordination failure when securing against an exotic disease where farmer efforts complement and communicating actions are important. The last arises from absence of a risk market where an adverse infrastructural support externality could be managed by disease outbreak insurance.
Changes in food choice patterns in a weight loss intervention
Authors: Grafenauer Sara J. , Tapsell Linda C. , Beck Eleanor J. , Batterham Marijka J.
Published: April 2015

Aim

Analyses of changes in food choice patterns made during weight loss may be informative for practice. In this research, food categorisation may be critical. The aim of the present study was to identify key changes in food choice patterns in weight loss trials.

Methods

Changes in dietary patterns between baseline and three months were analysed for 231 participants from two weight loss trials in terms of grams of food, kilojoules and the number of food serves consumed. Two food categorisation systems were applied using six more traditional food groups and 17 newly defined food categories considering national food guidance systems, and specific criteria, including the scientific evidence on the relationships between consumption of specific foods and health outcomes associated with weight management.

Results

After three months, there was no significant change in the total weight of food consumed, yet mean energy intakes decreased by more than 3000 kJ. Where six categories were applied, all groups except milk and milk alternatives were altered by the diet prescription. However, with 17 categories, subtle changes were more clearly demonstrated. For example, the 17 categories showed increased intake of low‐fat dairy foods and decreased intake of fatty meats, non‐wholegrain (refined) cereals specifically, and non‐core foods and drinks more broadly.

Conclusions

Changes in food choice patterns can be identified during weight loss trials. Applying a greater number of categories in the analysis enables a greater identification of changes in choice of key foods reflecting actual dietary change.