bluuebunny/crossref_metadata_2025 huggingface dataset:
Property $(T_B)$ and Property $(F_B)$ restricted to a representation without non-zero invariant vectors
Authors: Tanaka Mamoru
Published: February 2015

In this paper, we give a necessary and sufficient condition for a finitely generated group to have a property like Kazhdan's Property

(T)

restricted to one isometric representation on a strictly convex Banach space without non-zero invariant vectors. Similarly, we give a necessary and sufficient condition for a finitely generated group to have a property like Property

(FH)

restricted to the set of the affine isometric actions whose linear part is a given isometric representation on a strictly convex Banach space without non-zero invariant vectors. If the Banach space is the

\ell^p

space

(1<p<\infty)

on a finitely generated group, these conditions are regarded as an estimation of the spectrum of the

p

-Laplace operator on the

\ell^p

space and on the

p

-Dirichlet finite space respectively.
The Atiyah conjecture for the Hecke algebra of the infinite dihedral group
Authors: Okun Boris , Scott Richard
Published: February 2015

We prove a generalized version of the Strong Atiyah Conjecture for the infinite dihedral group

W

, replacing the group von Neumann algebra

\mathcal N W

with the Hecke–von Neumann algebra

\mathcal N_qW

.
On the classification of free Bogoljubov crossed product von Neumann algebras by the integers
Authors: Raum Sven
Published: February 2015

We consider crossed product von Neumann algebras arising from free Bogoljubov actions of

\mathbb Z

. We describe several presentations of them as amalgamated free products and cocycle crossed products and give a criterion for factoriality. A number of isomorphism results for free Bogoljubov crossed products are proved, focusing on those arising from almost periodic representations. We complement our isomorphism results by rigidity results yielding non-isomorphic free Bogoljubov crossed products and by a partial characterisation of strong solidity of a free Bogoljubov crossed products in terms of properties of the orthogonal representation from which it is constructed.
Pseudo-Anosov subgroups of fibered 3-manifold groups
Authors: Dowdall Spencer , Kent IV Richard P. , Leininger Christopher J.
Published: February 2015

Let

S

be a hyperbolic surface and let

\mathring{S}

be the surface obtained from

S

by removing a point. The mapping class groups

\mathrm {Mod}(S)

and

\mathrm {Mod}(\mathring{S})

fit into a short exact sequence

1 \to \pi_1(S) \to \mathrm {Mod}(\mathring{S}) \to \mathrm {Mod}(S) \to 1.

If

M

is a hyperbolic

3

-manifold that fibers over the circle with fiber

S

, then its fundamental group fits into a short exact sequence

1 \to \pi_1(S) \to \pi_1(M) \to \mathbb Z \to 1

that injects into the one above. We show that, when viewed as subgroups of

\mathrm {Mod} (\mathring{S})

, finitely generated purely pseudo-Anosov subgroups of

\pi_1(M)

are convex cocompact in the sense of Farb and Mosher. More generally, if we have a

\delta

-hyperbolic surface group extension

1 \to \pi_1(S) \to \Gamma_\Theta \to \Theta \to 1,

any quasiisometrically embedded purely pseudo-Anosov subgroup of

\Gamma_\Theta

is convex cocompact in

\mathrm {Mod}(\mathring{S})

. We also obtain a generalization of a theorem of Scott and Swarup by showing that finitely generated subgroups of

\pi_1(S)

are quasiisometrically embedded in hyperbolic extensions

\Gamma_\Theta

.
Transversally pseudoconvex semiholomorphic foliations
Authors: Mongodi Samuele , Tomassini Giuseppe
Published: February 2015

A
semiholomorphic foliations of type (n, d)
is a differentiable real manifold

X

of dimension

2n+d

, foliated by complex leaves of complex dimension

n

. The aim of the present note is to outline some results obtained in studying such spaces along the lines of the classical theory of complex spaces. Complete proofs will appear elsewhere.
Some applications of numerosities in measure theory
Authors: Benci Vieri , Bottazzi Emanuele , Di Nasso Mauro
Published: February 2015

We present some applications of the notion of numerosity to measure theory, including the construction of a non-Archimedean model for the probability of infinite sequences of coin tosses.
On the critical polynomial of functionals related to $p$-area (for $1 < p < \infty$) and $p$-Laplace $(1 < p≤2)$ type operators
Authors: Cingolani Silvia , Degiovanni Marco , Vannella Giuseppina
Published: February 2015

We consider a class of quasilinear elliptic equations whose principal part includes the

p

-area (for

1 < p < \infty

) and the

p

-Laplace (for

1 < p≤ 2)

operator. For the critical points of the associated functional, we provide estimates of the corresponding critical polynomial.
On a Dirichlet problem with $p$-Laplacian and asymmetric nonlinearity
Authors: Marano Salvatore A. , Papageorgiou Nikolaos S.
Published: February 2015

The existence of at least two nonnegative smooth solutions to a homogeneous Dirichlet problem with

p

-Laplacian and reaction (

p

–1)-linear, but asymmetric, at ±

\infty

is investigated through variational and truncation techniques. The case

p = 2

is separately examined, obtaining a third nontrivial smooth solution via Morse’s theory.
Multiplicity of solutions of nonlinear scalar field equations
Authors: Molle Riccardo , Passaseo Donato
Published: February 2015

In this Note we present new multiplicity results for the solutions of nonlinear elliptic problems of the form

-\Delta u +a(x)u=|u|^{p-1}u

in

\mathbb R^N

,

u\in H^1(\mathbb R^N)

, where

N\ge 2

,

p>1

,

p<{N+2\over N-2}

if

N\ge 3

,

a\in L^{N/2}_{\mathrm {loc}} (\mathbb R^N)

,

\inf_{\mathbb R^N}a>0

. In particular, we have infinitely many positive solutions when there exists

a_\infty>0

such that

\lim_{|x|\to\infty}a(x)=a_\infty

and

\lim_{|x|\to\infty}[a(x)-a_\infty]\,e^{\eta|x|}=+\infty

\forall\eta>0

.
Sets of admissible shifts of convex measures
Authors: Arutyunyan Lavrentin M. , Kosov Egor D.
Published: February 2015

We prove that for any convex probability measure on a linear space the set of its non-singular shifts is convex and the set of its equivalent shifts is a linear subspace.
Analysis of Plastic Oil-Gas Separator for Diesel Engine Valve Chamber Cover
Authors: Xinjie Zhang
Published: February 2015

Three different configurations of plastic oil-gas separator for diesel engine valve chamber cover were studied using numerical simulations. The distribution of flow velocity, pressure and oil droplets collection from simulation results were assessed to find out an optimum design for the oil-gas separator. Further, the oil-gas separation efficiency from simulation and experimental test was also reviewed to verify the simulation model as well as selection of the best design amongst the considered three configurations of the oil-gas separator.
Experimental Evaluation of an Empirical Model for Wedge Disc Brake using Box-Behnken Design
Authors: Ghazaly N.M. , Makrahy M.M. , Gwwad K.A.A.E. , Mahmoud K.R. , Tawwab A.M.A.E.
Published: February 2015

This article is a case study of Box-Behnken design application for development and evaluation a new empirical model to predict the performance of wedge disc brake. Box-Behnken design is used to study the applied pressure, rotational speed, wedge inclination angle and quantity of water spraying. A total of 27 experimental tests are conducted using brake dynamometer to estimate the main and interaction effect of these parameters. The results of analysis of variance for the braking forces from the input parameters are obtained to evaluate the goodness of the developed empirical model through F- and P-values. It is found that a strong correlation between the empirical regression model and the actual results. Moreover, in order to confirm the validity of the empirical model, additional 16 experimental tests are carried out using Taguchi method. The results showed a good agreement between the predicted empirical model and experimental results. This indicates that the developed empirical model based on operating parameters can be used successfully to predict the wedge disc brake performance.
Dry Contact and Coupled Thermomechanical Analyses of Brake Disc-Pad using Finite Element Simulation
Authors: Belhocine Ali , Ghazali Nouby Mahdi , Abdullah Oday Ibraheem
Published: February 2015

The motivation of this work is to identify the thermal effects on the structural and contact behaviour of a disc-pad assembly using a finite element approach. The first analysis is performed on the disc-pad model without the presence of thermal properties. Structural performance of the disc-pad model such as deformation and Von Mises stress is predicted. Next, thermomechanical analysis is performed on the same disc-pad model with the inclusion of convection, adiabatic and heat flux elements. The prediction results of temperature distribution, deformation, stress and contact pressure are presented. Comparison of the structural performance between the mechanical and thermomechanical is also made. Three disc-pad designs are assessed using the developed finite element model.
Investigation of Vehicle Parameters in Regenerative Coil Suspension Design
Authors: Selvan T.A. , Navin S. , Ram Ganesh K.R.
Published: February 2015

Regenerative type suspensions are employed to recover energy that is unproductively dissipated in dampers in automotive suspension system. In order to effectively recover energy from suspension, an attempt has been made in the design to capitalize the vehicle parameters and concoct a suitable linear generator in unison with helical spring. The performance characteristics drawing suitable inferences between the vehicle parameters and suspension specifications are well investigated.
Dry Sliding Wear and Friction of Aluminium Alloy Silicon Carbide Particulates Reinforced Composites
Authors: Muthukumar S. , Mathiyalagan P. , Mariappan R. , Jayavelu S.
Published: February 2015

In this work, the dry sliding wear behaviour and friction characteristics of aluminium alloy Al6061 silicon carbide particulates (SiCp) of size 43 Âµm reinforced composites were evaluated through laboratory experiments. The content of SiCp in the alloy was varied from 5% to 35% in steps of 5% by weight. The metal matrix composites were manufactured using stir casting technique. A pin-on-disc wear testing machine was used to evaluate the wear rate, in which an EN-31 steel disc was used as a counter face. Results indicated that the wear rates of the composites were lower than that of the matrix alloy and further reduction in wear rate was achieved by increasing the SiCp content. The wear rate increased for an increase in the load and sliding velocity. Increase in the applied load increased the wear severity by changing the wear mechanism from abrasion to particle cracking. The observations have been explained using scanning electron microscopy analysis of the worn surfaces. The coefficient of friction was evaluated using friction forces measured from the tests. The coefficient of friction decreased for an increase in the SiCp content at low sliding velocity.
Process and Content of DSM-5
Authors: Widiger Thomas A. , Crego Cristina
Published: February 2015

The third edition of the American Psychiatric Association's (APA) Diagnostic and Statistical Manual of Mental Disorders was a highly successful revision in large part because it was tremendously innovative. The authors of the fifth edition intended their version to provide another paradigm shift. However, the process of its construction was riddled with problems and controversies. Discussed herein is the presence of the internet, confidentiality contracts, no gold standard, and the inadequate documentation of empirical support. Also discussed was the failed attempt to provide a paradigm shift. Recommendations for the construction of future editions of the diagnostic manual are provided.
The Impact of DSM-5 on Autism Spectrum Disorder
Authors: Tsai Luke Y.
Published: February 2015

This paper reviews the evolution of the definition and diagnostic criteria of Autism Spectrum Disorder (ASD), the external validity of ASD subtypes, and the impacts of DSM-5 ASD on future studies of ASD epidemiology and genetics; on the treatments or interventions of individuals with ASD; and on the economy of health costs. Overall, it seems that the implementation of DSM-5 ASD may cause more negative results than provides positive influences.
The Potential Contribution of the Cognitive-Behavioral Model for the Classification of Emotional Disorders
Authors: Hofmann Stefan G.
Published: February 2015

The fifth edition of the Diagnostic and Statistical Manual (DSM-5) has been criticized for using arbitrary criteria to define mental disorders based on subjective data. The Research Domain Criteria (RDoC) initiative offers an alternative system that also considers biological and behavioral data, but shares the DSM-5's reliance on the latent disease model. Moreover, neither the DSM-5 nor RDoC provides any concrete treatment guidelines. In contrast, the cognitive behavioral model offers an empirically-based framework for a treatment-relevant classification system by focusing on maintaining rather than initiating factors. In contrast to the latent disease model of the DSM-5 and RDoC, the cognitive-behavioral framework is consistent with a complex causal network system network approach, which assumes that maladaptive cognitions and behaviors settle into a pathological state causing emotional distress. This framework offers concrete treatment implications while avoiding many shortcomings of a latent disease model.
Classification of Psychopathology and Unifying Theory the Ingredients of a Darwinian Paradigm Shift in Research Methodology
Authors: Mansell Warren , Carey Timothy A. , Tai Sara J.
Published: February 2015

The field of psychopathology needs a paradigm shift to revitalise its research methodology and translational practice. We describe Darwin's transformation of biology and its implications for science and culture, and we infer the implications of an analogous approach to psychopathology. Darwin challenged the assumptions of the biological classification system with compelling evidence to support a quantifiable, mechanistic theory of change across all life. Specifically, he showed that species were changeable, that individuals showed substantial variation in their features, and that these features were functional adaptations to the environment. Similarly, there is substantial evidence of continuous change, shared symptoms and functionality across the categories of psychiatric classification. Our novel research methodology, inspired by perceptual control theory, include both qualitative and quantitative methods, and entail the study of universal processes within heterogeneous samples and studying dynamic processes prospectively within individual cases, drawing direct analogies with evolutionary dynamic systems (e.g. trade-offs, speciation).
DSM-5 and the Assessment of Childhood Anxiety Disorders: Meaningful Progress, New Problems, or Persistent Diagnostic Quagmires?
Authors: Chou Tommy , Cornacchio Danielle , Cooper-Vince Christine E. , Crum Kathleen I. , Comer Jonathan S.
Published: February 2015

Having passed the one-year anniversary of the initial DSM-5 publication, this paper presents a guiding summary of key areas of change—and lack thereof—across DSM definitions of disorders affecting anxious youth, and offers data-informed evaluations and commentaries clarifying the areas in which DSM-5 should be celebrated as a meaningful advancement in the assessment of child anxiety, diagnostic dilemmas in child anxiety assessment from previous DSM editions that remain unresolved in DSM-5, and areas in which DSM-5 may have actually introduced new problems into the assessment of child anxiety. We organize our review and commentary around five of the meaningful changes in DSM-5 with implications for the assessment of anxious youth: (1) the new classification of selective mutism as an anxiety disorder; (2) the removal of the social anxiety disorder “generalized” specifier and the new addition of a “performance-only” specifier; (3) the revised operationalization of agoraphobia and the decoupling of agoraphobia from panic disorder; (4) the creation of a new category—disruptive mood dysregulation disorder—for diagnosing youth presenting with chronic irritability and severe temper outbursts; and (5) the revised classification of anxiety disorders not otherwise specified in the DSM. We then turn our attention to discuss four areas of noted diagnostic dilemmas in the assessment of child anxiety from DSM-IV that remain unresolved in the new DSM-5: (1) the phenomenological overlap between the OCD and generalized anxiety disorder (GAD) definitions; (2) the phenomenological overlap between GAD and major depressive disorder (MDD) definitions; (3) differential diagnostic utility across the separation anxiety disorder symptoms; and (4) the extent to which youth presenting with multiple marked and persistent fears should be assigned multiple distinct diagnoses of specific phobia.
The Brave New World of Personality Disorder-Trait Specified: Effects of Additional Definitions on Coverage, Prevalence, and Comorbidity
Authors: Clark Lee Anna , Vanderbleek Emily N. , Shapiro Jaime L. , Nuzum Hallie , Allen Xia , Daly Elizabeth , Kingsbury Thomas J. , Oiler Morgan , Ro Eunyoe
Published: February 2015

The alternative dimensional model for personality disorder (PD) in DSM-5, Section III (DSM-5–III) includes two main criteria: (A) personality-functioning impairment, and (B) personality-trait pathology; provides specific functioning-and-trait criteria for six PD-type diagnoses; and introduces PD-trait specified (PD-TS), which requires meeting the general PD criteria and not meeting criteria for any specific PD type. We termed this Simple PD-TS and developed two additional definitions: Mixed PD-TS, meeting criteria for one or two PD types and having five or more additional pathological traits; and Complex PD-TS, meeting criteria for three or more PD types. In a mixed sample of 165 outpatients and 215 community adults screened to be at highrisk for PD, we investigated the effect of these additional definitions on coverage, prevalence, comorbidity, and within-diagnosis heterogeneity, and conclude that eliminating the PD-type diagnoses and thus having PD-TS as the only PD diagnosis would be both more parsimonious and more useful clinically.
Integrating dimensional assessment and categorical diagnosis in DSM-5: The benefits and challenges of the paradigm shift for the anxiety disorders
Authors: LeBeau Richard , Bögels Susan , Möller Eline , Craske Michelle
Published: February 2015

With DSM-5, the American Psychiatric Association (APA) strongly encourages clinicians and researchers to supplement traditional categorical diagnoses with dimensional ratings of severity. To that end, several scales have been created for or adopted by the APA that are brief, psychometrically sound, and easily accessible. Despite these scales' inclusion in the text and online, awareness of them remains low one year after DSM-5's publication. In the present paper, we review the APA's guidelines for dimensional assessment and examine several issues relevant to dimensional assessment including: persuading clinicians of the utility of dimensional assessment, raising awareness of the scales, establishing guidelines for interpretation, incorporating data from multiple informants, assessment across diverse groups, and the risks and benefits of scales accessible to the general public. These issues will be illustrated through the example of the anxiety disorders, due to the fact that this diagnostic category has made significant progress with regard to dimensional classification.
Imagine there's no diagnosis, it's easy if you try
Authors: Kinderman Peter
Published: February 2015

The recent discussions over the reliability, validity, utility, humanity and epistemology of psychiatric diagnosis have had wider implications than might at first sight be apparent. Diagnosis is, for many people, both the entry-point to services and the starting-point for public debate. Challenges to the scientific and professional basis for diagnosis, therefore, can have profound implications. Such is the dominance of traditional diagnostic thinking about mental health care that it is often wrongly assumed that there is little alternative – or that any possible alternatives would require lengthy and expensive periods of development. In fact, there is no present impediment to the development of new ways of thinking and delivering services, and especially no impediment to practical and scientifically valid alternatives to diagnosis.
Science Teachers’ Assessment and Grading Practices in Swedish Upper Secondary Schools
Authors: Carmen Gómez Maria del , Jakobsson Anders
Published: February 2015

This study examines science teachers’ assessment and grading practices as well as student participation in the assessment process in the upper secondary school. The teachers were asked about how and when they assess students and what was crucial when grading students. We asked when they considered students to have developed the following knowledge criteria: aptitude for critical thinking, analytical and practical skills and how they assessed students regarding these skills. We report overall evidence-based assessment practices from the teachers’ comments in face-to-face interviews. Teachers’ comments are closely aligned and associated with long-established beliefs. The assessment and grading practices were found to be at odds with modern perspectives of assessment as well as its role in learning.
Comportamiento de los sedimentos fluviales en Honduras. Rendimiento y pérdida de suelo Zona Central y Oriental
Authors: Ávalos Lingan Roberto Fredy
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1815
Análisis de la contaminación del Río Choluteca y sus efectos sobre la población a su paso por Tegucigalpa
Authors: Ponce de Montoya Beatriz
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1816
El manejo del agua en Honduras
Authors: Ochoa Álvarez Rodolfo
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1818
Del sexo a la rosa: Erotismo en la poesía de Clementina Suárez
Authors: Torres Claudia S
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1819
Vinculo estrategia de operaciones-tecnología en la industria hondureña: Ajuste de selectión
Authors: Ortega Jimenéz César H
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1821
Registro de un nuevo helecho para la Flora de Honduras
Authors: Hernández Cibrian Ruth Karina , Nelson Sutherland Cyril Hardy
Published: February 2015

DOI: http://dx.doi.org/10.5377/rct.v0i2.1822
Different types of theta rhythmicity are induced by social and fearful stimuli in a network associated with social memory
Authors: Tendler Alex , Wagner Shlomo
Published: February 2015

Rhythmic activity in the theta range is thought to promote neuronal communication between brain regions. In this study, we performed chronic telemetric recordings in socially behaving rats to monitor electrophysiological activity in limbic brain regions linked to social behavior. Social encounters were associated with increased rhythmicity in the high theta range (7–10 Hz) that was proportional to the stimulus degree of novelty. This modulation of theta rhythmicity, which was specific for social stimuli, appeared to reflect a brain-state of social arousal. In contrast, the same network responded to a fearful stimulus by enhancement of rhythmicity in the low theta range (3–7 Hz). Moreover, theta rhythmicity showed different pattern of coherence between the distinct brain regions in response to social and fearful stimuli. We suggest that the two types of stimuli induce distinct arousal states that elicit different patterns of theta rhythmicity, which cause the same brain areas to communicate in different modes.
Inhibition of mutant EGFR in lung cancer cells triggers SOX2-FOXO6-dependent survival pathways
Authors: Rothenberg S Michael , Concannon Kyle , Cullen Sarah , Boulay Gaylor , Turke Alexa B , Faber Anthony C , Lockerman Elizabeth L , Rivera Miguel N , Engelman Jeffrey A , Maheswaran Shyamala , Haber Daniel A
Published: February 2015

Treatment of EGFR-mutant lung cancer with erlotinib results in dramatic tumor regression but it is invariably followed by drug resistance. In characterizing early transcriptional changes following drug treatment of mutant EGFR-addicted cells, we identified the stem cell transcriptional regulator SOX2 as being rapidly and specifically induced, both in vitro and in vivo. Suppression of SOX2 sensitizes cells to erlotinib-mediated apoptosis, ultimately decreasing the emergence of acquired resistance, whereas its ectopic expression reduces drug-induced cell death. We show that erlotinib relieves EGFR-dependent suppression of FOXO6, leading to its induction of SOX2, which in turn represses the pro-apoptotic BH3-only genes BIM and BMF. Together, these observations point to a physiological feedback mechanism that attenuates oncogene addiction-mediated cell death associated with the withdrawal of growth factor signaling and may therefore contribute to the development of resistance.
Superthermal electron transport model for Mars
Authors: Xu Shaosui , Liemohn Michael W.
Published: February 2015

This study presents a multistream superthermal electron transport model for the Mars space environment. This model includes the magnetic inhomogeneity effects, which is vital to understand electron motion around Mars. The convergence tests on the step sizes of variables are carried out and appropriate grid setups are determined. In addition, we have examined three physical parameters, F10.7 values, thermal electron/plasma density, and neutral densities. Through the investigation of F10.7 values, an interesting fact about the Hinteregger model is found that the photon flux of each wavelength is scaled differently. The resultant photoelectron fluxes also show a nonuniform percentage of increase. The results of plasma density and neutral densities tests are consistent with previous theories, such as the expected degradation of fluxes in the low‐energy range with increased thermal electron/plasma density, and the elevated peak altitude of photoelectron fluxes with increased neutral densities. The examination of these physical parameters indicates the model's ability to simulate various environments and verifies the model's performance. Finally, a data‐model comparison is carried out and the modeled omnidirectional fluxes agree well (within a factor of 2) with the observation.
Dust deposition in the eastern Indian Ocean: The ocean perspective from Antarctica to the Bay of Bengal
Authors: Grand Maxime M. , Measures Christopher I. , Hatta Mariko , Hiscock William T. , Buck Clifton S. , Landing William M.
Published: February 2015

Atmospheric deposition is an important but still poorly constrained source of trace micronutrients to the open ocean because of the dearth of in situ measurements of total deposition (i.e., wet + dry deposition) in remote regions. In this work, we discuss the upper ocean distribution of dissolved Fe and Al in the eastern Indian Ocean along a 95°E meridional transect spanning the Antarctic margin to the Bay of Bengal. We use the mixed layer concentration of dissolved Al in conjunction with empirical data in a simple steady state model to produce 75 estimates of total dust deposition that we compare with historical observations and atmospheric model estimates. Except in the northern Bay of Bengal where the Ganges‐Brahmaputra river plume contributes to the inventory of dissolved Al, the surface distribution of dissolved Al along 95°E is remarkably consistent with the large‐scale gradients in mineral dust deposition and multiple‐source regions impacting the eastern Indian Ocean. The lowest total dust deposition fluxes are calculated for the Southern Ocean (66 ± 60 mg m−2 yr−1) and the highest for the northern end of the south Indian subtropical gyre (up to 940 mg m−2 yr−1 at 18°S) and in the southern Bay of Bengal (2500 ± 570 mg m−2 yr−1). Our total deposition fluxes, which have an uncertainty on the order of a factor of 3.5, are comparable with the composite atmospheric model data of Mahowald et al. (2005), except in the south Indian subtropical gyre where models may underestimate total deposition. Using available measurements of the solubility of Fe in aerosols, we confirm that dust deposition is a minor source of dissolved Fe to the Southern Ocean and show that aeolian deposition of dissolved Fe in the southern Bay of Bengal may be comparable to that observed underneath the Saharan dust plume in the Atlantic Ocean.
Baroclinic energy flux at the continental shelf edge modified by wind‐mixing
Authors: R. Stephenson Gordon , Hopkins Joanne E. , Mattias Green J. A. , Inall Mark E. , Palmer Matthew R.
Published: February 2015

Temperature and current measurements from two moorings onshore of the Celtic Sea shelf break, a well‐known hot spot for tidal energy conversion, show the impact of passing summer storms on the baroclinic wavefield. Wind‐driven vertical mixing changed stratification to permit an increased on‐shelf energy transport, and baroclinic energy in the semidiurnal band appeared at the moorings 1–4 days after the storm mixed the upper 50 m of the water column. The timing of the maximum in the baroclinic energy flux is consistent with the propagation of the semidiurnal internal tide from generation sites at the shelf break to the moorings 40 km away. Also, the ∼3 day duration of the peak in M2 baroclinic energy flux at the moorings corresponds to the restratification time scale following the first storm.
Ion beta dependence on the development of Alfvénic fluctuations in reconnection jets
Authors: Higashimori Katsuaki , Hoshino Masahiro
Published: February 2015

The generation of magneto‐hydro‐dynamic (MHD) to ion‐scale fluctuations in collisionless magnetic reconnection is discussed using a two‐dimensional electromagnetic hybrid code. It is shown that reconnection jets become turbulent specifically in low beta conditions, βi0<0.1–0.2 (where βi0 is the ion plasma beta in initial inflow regions). The fluctuations observed in reconnection jets consist of outgoing Alfvénic fluctuations. As probable candidates for the origin of Alfvénic fluctuations, this study focused on the dynamics in the plasma sheet boundary layer (PSBL) and a current sheet. We suggest that PSBL ion dynamics play an important part in excitation and suppression of waves. PSBL beam ions drive Alfvén waves in MHD to ion scale, kλi<0.5 (λi is ion inertial length), independent of βi0. On the other hand, because the beam temperature is highly correlated with that of inflowing ions, the waves decay by cyclotron damping as the value of the inflow ion beta increases. Local linear analysis suggests that this damping signature changes in βi0∼0.1–0.2 and suppresses the wave activity of Alfvén modes in high beta reconnection jets.
Interpreting Ulysses data using inverse scattering theory: Oblique Alfvén waves
Authors: Wheeler Harry R. , Reynolds M. A. , Hamilton R. L.
Published: February 2015

Solitary wave structures observed by the Ulysses spacecraft in the solar wind were analyzed using both inverse scattering theory and direct numerical integration of the derivative nonlinear Schrödinger (DNLS) equation. Several of these structures were found to be consistent with soliton solutions of the DNLS equation. Such solitary structures have been commonly observed in the space plasma environment and may, in fact, be long‐lived solitons. While the generation of these solitons may be due to an instability mechanism, e.g., the mirror instability, they may be observable far from the source region due to their coherent nature.
The global context of the 14 November 2012 storm event
Authors: Hwang K.‐J. , Sibeck D. G. , Fok M.‐C. H. , Zheng Y. , Nishimura Y. , Lee J.‐J. , Glocer A. , Partamies N. , Singer H. J. , Reeves G. D. , Mitchell D. G. , Kletzing C. A. , Onsager T.
Published: February 2015

From 2 to 5 UT on 14 November 2012, the Van Allen Probes observed repeated particle flux dropouts during the main phase of a geomagnetic storm as the satellites traversed the post‐midnight to dawnside inner magnetosphere. Each flux dropout corresponded to an abrupt change in the magnetic topology, i.e., from a more dipolar configuration to a configuration with magnetic field lines stretched in the dawn‐dusk direction. Geosynchronous GOES spacecraft located in the dusk and near‐midnight sectors and the LANL constellation with wide local time coverage also observed repeated flux dropouts and stretched field lines with similar occurrence patterns to those of the Van Allen Probe events. THEMIS recorded multiple transient abrupt expansions of the evening‐side magnetopause ∼20–30 min prior to the sequential Van Allen Probes observations. Ground‐based magnetograms and all sky images demonstrate repeatable features in conjunction with the dropouts. We combine the various in situ and ground‐based measurements to define and understand the global spatiotemporal features associated with the dropouts observed by the Van Allen Probes. We discuss various proposed hypotheses for the mechanism that plausibly caused this storm‐time dropout event as well as formulate a new hypothesis that explains the combined in situ and ground‐based observations: the earthward motion of magnetic flux ropes containing lobe plasmas that form along an extended magnetotail reconnection line in the near‐Earth plasma sheet.
Multiscale seismic reflectivity of shallow thermoclines
Authors: Ker S. , Le Gonidec Y. , Marié L. , Thomas Y. , Gibert D.
Published: February 2015

Seismic oceanography is coming of age as an established technique of observation of the thermohaline structure of the ocean. The present paper deals with the seismic reflectivity of the Armorican Shelf seasonal thermocline, west of France, based on two seismic experiments performed with a sparker source. The peak frequency was 500 Hz for the ASPEX experiment, where the thermocline was located at 27 m water depth, and reduced to 400 Hz associated to a higher source level for the IFOSISMO experiment, where the thermocline was 12 m deeper. Despite these settings, only the first experiment could clearly highlight the thermocline reflector, providing the first seismic observation of a shallow oceanic structure. To better understand the limitation of high‐resolution seismic devices in detecting weak oceanic features, we develop a wavelet‐based seismic analysis and consider, as a first approximation, a simple thermocline modeled by a Gauss error function, allowing an analytical expression for the associated seismic reflectivity. We show that the acoustic impedance profile of the thermocline is mainly controlled by a sound velocity proportional to the temperature. We show that the seismic reflectivity is controlled by the reflection coefficient of the large‐scale structure of the thermocline and by an attenuation factor which depends on the ratio between the seismic wavelength and the characteristic size of the thermocline. Depending on this ratio, the strength of the thermocline‐related reflection may be too weak to be detected by seismic measurement.
Updated PMC trends derived from SBUV data
Authors: DeLand Matthew T. , Thomas Gary E.
Published: February 2015

Previous analysis of polar mesospheric clouds (PMCs) observed by Solar Backscatter Ultraviolet (SBUV) instruments found that long‐term variations in PMC brightness and occurrence frequency were anticorrelated with solar activity and that an increasing secular trend was present at most latitudes. In this paper, long‐term PMC variations are presented in terms of ice water content (IWC), a physically based variable which is easier to interpret than previously reported UV albedo values. This model‐based conversion from albedo to IWC removes most scattering angle effects. The derived long‐term PMC variations in the SBUV data set are qualitatively the same using either an empirically derived adjustment for local time effects or no adjustment (i.e., assuming cancelation of interannual variations in tidally induced amplitude and/or phase). When we use stratospheric ozone variations as a proxy for mesospheric temperature changes, as suggested by recent model studies, we can explain more of the long‐term IWC variability than if we use a linear trend. These results show that PMC ice water content in bright clouds increased rapidly from 1979 through the late 1990s and has been approximately constant from the late 1990s through 2013. The numerical value and sign of this trend during the last 15 years depend on the choice of end points and latitude band. Simultaneously, the solar response of IWC observed by SBUV has weakened during the most recent cycle in the Northern Hemisphere, but increased in the Southern Hemisphere.
An accurate and fast forward model of three‐dimensional electromagnetic wave scattering in a layered structure with multilayer rough interfaces
Authors: Wu Chao , Zhang Xiaojuan , Fang Guangyou , Shi Jiancheng , Liu Shiyin
Published: February 2015

We develop an accurate and fast forward model for calculating the compact closed‐form high‐order perturbative solutions of the problem of three‐dimensional (3‐D) radiation and propagation electromagnetic fields in a layered structure with multilayer rough interfaces. The proposed method for the fast forward model is first demonstrated by strictly theoretical formulas derivation in the framework of classical small perturbation method (SPM) without other else approximation and equivalent process. The kernel functions of high order are proposed for calculating the radar cross sections with more efficiency and clear physical meanings for better use in practice. What is more, we give the clear physical interpretation of the first‐order fully polarimetric electromagnetic wave scattering mechanism in the layered structure with multilayer rough interfaces. The proposed forward model is necessary to insure a successful inversion process. Furthermore, the high‐order SPM solutions derived by employing the proposed method are validated with existing methods and numerical results. Finally, we study the performance of the high‐order fully polarimetric electromagnetic wave scattering according to the numerical results and analyze the scattering enhancement phenomena.
Porphyrias
Authors: Besur Siddesh , Bonkovsky Herbert L
Published: February 2015

The porphyrias are a group of eight disorders of haem biosynthesis characterised by overproduction of haem precursors secondary to partial enzyme deficiencies or, in one porphyria, gain of function of the rate‐controlling enzyme of the pathway in erythroid cells. Patients suffer from acute neurovisceral attacks, always associated with overproduction of porphyrin precursors, skin lesions caused by photosensitisation by porphyrins or both together. All are inherited, apart from sporadic porphyria cutanea tarda. The three porphyrias in which acute attacks occur (acute intermittent porphyria, hereditary coproporphyria and variegate porphyria) and familial porphyria cutanea tarda are low penetrance autosomal dominant disorders and one is an X‐linked disorder. All others are autosomal recessive. Enzyme activities in the autosomal recessive porphyrias and in the homozygous variants of other porphyrias are usually less than 20% of normal.

Key Concepts

The porphyrias are disorders of haem biosynthesis.

Each of the eight porphyrias is caused by an abnormality of a different enzyme of haem biosynthesis.

Each enzyme abnormality leads to overproduction of haem precursors in a specific pattern that defines the disorder.

Overproduction of porphyrin precursors leads to acute neurovisceral attacks that characterise the three autosomal dominant acute porphyrias and one rare recessive porphyria.

Overproduction of porphyrins leads to photosensitisation of the skin with either skin fragility and blisters or, when only protoporphyrin accumulates, acute painful photosensitivity.

All autosomal dominant porphyrias have low clinical penetrance.

Most patients with the commonest inherited cutaneous porphyria, erythropoietic protoporphyria, have inherited a low expression ferrochelatase allele trans to a deleterious ferrochelatase mutation.

The prevalence of erythropoietic protoporphyria and the proportion of families showing pseudo‐dominant inheritance are determined by the population frequency of the low expression allele.
Protein Kinases in the Era of Precision Medicine
Authors: Moiani Davide , Tabaian Amir , Suto Robert K , Doyle David M , Sowadski Janusz M
Published: February 2015

Precision medicine signals the beginning of an era in which each patient is a distinct individual from a diagnostic, treatment and health management perspective. In this article, we present a description of a methodology to develop a therapy, based on kinase inhibitors, and a strategy to retarget a therapy in rapid response to a patient's relapse. The idea is to translate the genomic data of an evolving cancer into a three‐dimensional structure to enable a better understanding of the mechanism of resistance, and to then control it with a specific and precise drug targeting therapy based on the
SNP
resistance mutation. In many cases, a combination of approved drug treatments can assist in controlling the disease. However, the clinical trials selection process is changing from randomised populations to selected populations so that genetic tests can more clearly define the presence of specific mutations in the relapsing patient. This knowledge of the subpopulation will also help identify new small molecules that target multiple kinases based on their specificity profiles. The tendency at present is to define an eligibility criteria based on the genetics of the patients.

Key Concepts

The crystallographic characterisation of kinase inhibitor complexes drove the approval of 27 drugs targeting kinome.

Organising the kinase three‐dimensional (3D) structures in a uniquely aligned library has enabled us to predict the functionality, in a 3D space, of any variants that are found in a patient's genome.

Accurate specificity profiles of approved kinase inhibitors inform a rational combination of inhibitors for a specific genetic subpopulation of patients.

Kinase inhibitor therapy can be matched to critical mutations in the kinase 3D structure and a companion diagnostics approach can then be used in specific clinical trial to more accurately select patients.

The targeting of both the kinase‐activating mutation and the drug‐resistant mutations can be optimised by the chemistry of the intermediate conformations of the DFG motif.

The drug resistance requires frequent genetic monitoring utilising a liquid biopsy.

Overcoming the drug resistance on the target is possible by combining approved drugs based on the enhanced knowledge of the highly accurate specificity profiles.
Vertebrate Embryo: Neural Patterning
Authors: Itasaki Nobue
Published: February 2015

Neural patterning is the process of providing regional identities in neural cells in accordance with their location in the neural tube. Allocation of regional identities is prerequiscent for the following processes of neuronal circuit formation. The neural tube is longitudinal among the body axis thus having anterior–posterior polarity (rostral–caudal in aves, future superior–inferior in adult human). It also has dorsal–ventral polarity and right and left sides. Neural patterning commences as the neural induction takes place progressively in the anterior to posterior direction. By signalling and tissue interaction, the neural tube is divided into the forebrain, midbrain, hindbrain and the spinal cord along the anterior–posterior axis. Further divisions follow to produce differentiation of functional compartments that are defined by the combinatorial expression of molecular markers. The same principle, the initial subdivision by signalling followed by refined compartmentalisation, applies to the acquisition of dorsal–ventral specification as well.

Key Concept

Depending on the actual position in the body, cells are specified with respect to the position (positional specification), thus positional identity is acquired. Cells then interpret their positions to differentiate accordingly, thus spatial patterns are formed (see Wolpert, 2011).

Neural patterning is the process through which neural progenitors acquire positional identities. The initial allocation of positional information is governed by signalling mechanisms. This is followed by expression of transcription factors, such asHoxgenes for the anterior–posterior axis.
Foot‐and‐Mouth Disease
Authors: Belsham Graham J , Charleston Bryan , Jackson Terry , Paton David J
Published: February 2015

Foot‐and‐mouth disease (
FMD
) is an economically important, highly contagious disease of cloven‐hoofed animals characterised by the appearance of vesicles (blisters) on the feet and in, and around, the mouth. The causative agent, foot‐and‐mouth disease virus (
FMDV
), was the first mammalian virus to be discovered. It has a ribonucleic acid (
RNA
) genome enclosed within a protein coat (capsid). The virus replicates very rapidly within the cytoplasm of cells. The
RNA
genome has to function both as a messenger
RNA
(
mRNA
) and as a template for
RNA
replication. The
RNA
encodes a single large polyprotein that is processed, by virus‐encoded proteases, to about 12 mature products (plus functionally important precursors) that are required for virus replication and assembly. Some of these viral proteins modify host cell activities to block antivirus defence systems. Thus, this small virus displays a remarkably complex array of biological activities.

Key Concepts

Foot‐and‐mouth disease has worldwide economic importance.

Foot‐and‐mouth disease virus (FMDV) is able to infect a wide range of different cloven‐hoofed animals.

Seven different serotypes of FMDV are known and there is considerable antigenic diversity within each serotype.

FMDV uses specific cell‐surface molecules (including specific integrins) as receptors to gain entry into cells.

The viral RNA is sufficient to initiate an infection.

The RNA displays diverse activities, as a messenger RNA, as a template for RNA replication and as the genome.

The virus‐encoded polyprotein is processed by proteases present within itself to make about 12 different mature products (plus important precursors).

Viral proteins are required both for viral RNA replication and virus assembly; in addition, some also modify specific cellular functions in order to block host antiviral responses.

Current vaccines rely on the production and then chemical inactivation of infectious virus.

Non‐infectious empty capsid particles can be produced, which are candidates as new, safer vaccines.