bluuebunny/crossref_metadata_2025 huggingface dataset:
Prediction of microstructure and mechanical properties of line pipe welded joints based on hardness map
Authors: Kavousi Sisi A. , Mirsalehi S. E.
Published: July 2015

In this article, the variation of hardness in cross-section of X52 microalloyed steel joints before and after post-weld heat treatment and also the relationship of hardness with ultimate tensile strength, yield strength and microstructure have been investigated. For this purpose, the specimens were prepared in two conditions of as welded and post-weld heat treated, and the hardness maps of their cross-section were provided. Then, some equations were suggested to correlate the obtained hardness with the grain size and tensile and yield strengths. The equations made it possible to predict tensile and yield strengths with high accuracy. According to the results, the maximum hardness and strength belong to the weld junction. Normalisation of the joints at 950°C reduced significantly the hardness difference (and also the strength difference) in various joint areas and homogenised the microstructure considerably. The grain size distribution was also modelled acceptably for the post-weld heat treated joint, and the grain size map was obtained.
Microstructure and deformation behaviour of laser welded dissimilar dual phase steel joints
Authors: Dong D. , Liu Y. , Wang L. , Yang Y. , Jiang D. , Yang R. , Zhang W.
Published: July 2015

The microstructure, microhardness, tensile properties, deformation and fracture behaviour of the Nd:YAG laser welded dissimilar joints between 780 and 980 MPa dual phase steels over a wide strain rate range were investigated. The welded joint shows hardening in fusion zone, supercritical and intercritical heat affected zones and softening in subcritical heat affected zones. For the dissimilar welded joint, the changing trend of the ductility is similar to those of the base metals with respect to the strain rate. The reason for the strain rate sensitivity of the failure location of the welded joint is that the major factor influencing the failure location changes from the content of ferrite to the content of ferrite/martensite interface with increasing strain rate.
Characteristics of short-circuit behaviour and its influencing factors in self-shielded flux-cored arc welding
Authors: Zhu Z. , Fan K. , Liu H. , Ma G.
Published: July 2015

The characteristics of short-circuit behaviour during the process of self-shielded flux-cored arc welding and its corresponding welding electric information are investigated by a synchronous acquisition system of high-speed images and welding electric information. The research results show that when the welding arc between the wire tip and the weld pool extinguishes, a short-circuit event occurs and its corresponding arc voltage is below ∼10 V, which can be used to judge the occurrence of the short-circuit procedure. Meanwhile, the influence of welding process setting parameters on the short-circuit behaviour is explored in detail. The existence of liquid slag increases the difficulty of arc re-ignition, which makes it easy to produce weld defects. Therefore, the short-circuit procedure in self-shielded flux-cored arc welding should be avoided as much as possible.
Weldability assessment of friction stir spot welded lightweight alloys using pin and pinless tools
Authors: Shin H.-S. , de Leon M.
Published: July 2015

Friction stir spot welding (FSSW), a solid state welding process, can join materials that are difficult to joint by fusion welding processes. In this study, similar FSSW of lightweight alloy sheets, such as aluminium and magnesium alloys, was performed using tools without thread. The histories of vertical plunge load applied to lapped sheets and the temperature distribution around the stirred surface of the upper positioned sheet during friction stirring were examined. Friction stir spot welding characteristics were discussed regarding the lap shear failure load and fractographic observations after tensile shear tests. A retracted tool produced the highest lap shear failure load for similar aluminium welds, while a pin tool produced the highest lap shear failure load for similar magnesium welds. The failure mode that brought a combination of shear and pullout fracture produced the highest lap shear failure load, which was closely related to the geometry of the tool that developed the enlarged fracture path.
Influence of alloy type, peak temperature and constraint on residual stress evolution in Satoh test
Authors: Galler J. P. , DuPont J. N. , Siefert J. A.
Published: July 2015

The evolution of residual stress in welds is affected by a variety of factors such as joint design, welding parameters, material properties and the possible presence of phase transformations. The Satoh test can be useful as a method to understand differences in welding residual stresses among various materials. This study compares the evolution of residual stress measured in the Satoh test for ferritic and stainless steels. For weld thermal cycles with a peak temperature above Ac3, the ferritic alloys exhibit lower residual stresses than the austenitic alloys due to the well known reduction in stress from the martensitic or bainitic transformation. However, the residual stress levels among these alloys are similar for peak temperatures below Ac3. The application of constraint during both the heating and cooling portions of the thermal cycle affects the final magnitude of residual stress in a way that is not often considered.
Acylcarnitines are anticoagulants that inhibit factor Xa and are reduced in venous thrombosis, based on metabolomics data
Authors: Deguchi Hiroshi , Banerjee Yajnavalka , Trauger Sunia , Siuzdak Gary , Kalisiak Ewa , Fernández José A. , Hoang Linh , Tran Minerva , Yegneswaran Subramanian , Elias Darlene J. , Griffin John H.
Published: July 2015

Key Points

Untargeted and targeted metabolomics showed association of low plasma acylcarnitines levels with venous thrombosis risk. Long-chain acylcarnitines are anticoagulants that inhibit factor Xa by binding to factor Xa outside the γ-carboxy glutamic acid domain.
Evidence for Kinetic Limitations as a Controlling Factor of Ge Pyramid Formation: a Study of Structural Features of Ge/Si(001) Wetting Layer Formed by Ge Deposition at Room Temperature Followed by Annealing at 600 °C
Authors: Storozhevykh Mikhail S. , Arapkina Larisa V. , Yuryev Vladimir A.
Published: July 2015

The article presents an experimental study of an issue of whether the formation of arrays of Ge quantum dots on the Si(001) surface is an equilibrium process or it is kinetically controlled. We deposited Ge on Si(001) at the room temperature and explored crystallization of the disordered Ge film as a result of annealing at 600 °C. The experiment has demonstrated that the Ge/Si(001) film formed in the conditions of an isolated system consists of the standard patched wetting layer and large droplike clusters of Ge rather than of huts or domes which appear when a film is grown in a flux of Ge atoms arriving on its surface. We conclude that the growth of the pyramids appearing at temperatures greater than 600 °C is controlled by kinetics rather than thermodynamic equilibrium whereas the wetting layer is an equilibrium structure.

PACS:

Primary 68.37.Ef; 68.55.Ac; 68.65.Hb; 81.07.Ta; 81.16.Dn
Laser microdissection-based gene expression analysis in the aleurone layer and starchy endosperm of developing rice caryopses in the early storage phase
Authors: Ishimaru Tsutomu , Ida Masashi , Hirose Sakiko , Shimamura Satoshi , Masumura Takehiro , Nishizawa Naoko K. , Nakazono Mikio , Kondo Motohiko
Published: July 2015

Background

Rice endosperm is composed of aleurone cells in the outermost layers and starchy endosperm cells in the inner part. The aleurone layer accumulates lipids, whereas starchy endosperm mainly accumulates starch. During the ripening stage, the starch accumulation rate is known to be asynchronous, depending on the position of the starchy endosperm. Different physiological and molecular mechanisms are hypothesized to underlie the qualitative and quantitative differences in storage products among developing rice endosperm tissues.

Results

Target cells in aleurone layers and starchy endosperm were isolated by laser microdissection (LM), and RNAs were extracted from each endosperm tissue in the early storage phase. Genes important for carbohydrate metabolism in developing endosperm were analyzed using qRT-PCR, and some of the genes showed specific localization in either tissue of the endosperm. Aleurone layer-specific gene expression of a sucrose transporter, OsSUT1, suggested that the gene functions in sucrose uptake into aleurone cells. The expression levels of ADP-glucose pyrophosphorylase (AGPL2 and AGPS2b) in each endosperm tissue spatially corresponded to the distribution of starch granules differentially observed among endosperm tissues. By contrast, expressions of genes for sucrose cleavage—hexokinase, UDP-glucose pyrophosphorylase, and phosphoglucomutase—were observed in all endosperm tissues tested. Aleurone cells predominantly expressed mRNAs for the TCA cycle and oxidative phosphorylation. This finding was supported by the presence of oxygen (8 % concentration) and large numbers of mitochondria in the aleurone layers. In contrast, oxygen was absent and only a few mitochondria were observed in the starchy endosperm. Genes for carbon fixation and the GS/GOGAT cycle were expressed highly in aleurone cells compared to starchy endosperm.

Conclusions

The transcript level of AGPL2 and AGPS2b encoding ADP-glucose pyrophosphorylase appears to regulate the asynchronous development of starch granules in developing caryopses. Aleurone cells appear to generate, at least partially, ATP via aerobic respiration as observed from specific expression of identified genes and large numbers of mitochondria. The LM-based expression analysis and physiological experiments provide insight into the molecular basis of the spatial and nutritional differences between rice aleurone cells and starchy endosperm cells.
Body fatness during childhood and adolescence and breast density in young women: a prospective analysis
Authors: Bertrand Kimberly A. , Baer Heather J. , Orav E. John , Klifa Catherine , Shepherd John A. , Van Horn Linda , Snetselaar Linda , Stevens Victor J. , Hylton Nola M. , Dorgan Joanne F.
Published: July 2015

Introduction

Overweight and obesity in childhood and adolescence are associated with reduced breast cancer risk, independent of adult body mass index (BMI). These associations may be mediated through breast density.

Methods

We prospectively examined associations of early life body fatness with adult breast density measured by MRI in 182 women in the Dietary Intervention Study in Children (DISC) who were ages 25–29 at follow-up. Height, weight, and other factors were measured at baseline (ages 8–10) and annual clinic visits through adolescence. We used linear mixed-effects models to quantify associations of percent breast density and dense and non-dense breast volume at ages 25–29 with quartiles of age-specific youth body mass index (BMI) Z-scores, adjusting for clinic, treatment group, current adult BMI, and other well-established risk factors for breast cancer and predictors of breast density.

Results

We observed inverse associations between age-specific BMI Z-scores at all youth clinic visits and percent breast density, adjusting for current adult BMI and other covariates (all p values <0.01). Women whose baseline BMI Z-scores (at ages 8–10 years) were in the top quartile had significantly lower adult breast density, after adjusting for current adult BMI and other covariates [least squares mean (LSM): 23.4 %; 95 % confidence interval (CI): 18.0 %, 28.8 %] compared to those in the bottom quartile (LSM: 31.8 %; 95 % CI: 25.2 %, 38.4 %) (p trend <0.01). Significant inverse associations were also observed for absolute dense breast volume (all p values <0.01), whereas there were no clear associations with non-dense breast volume.

Conclusions

These results support the hypothesis that body fatness during childhood and adolescence may play an important role in premenopausal breast density, independent of current BMI, and further suggest direct or indirect influences on absolute dense breast volume.

Clinical Trials Registration Number

NCT00458588; April 9, 2007
Measuring disease activity in adults with systemic lupus erythematosus: the challenges of administrative burden and responsiveness to patient concerns in clinical research
Authors: Mikdashi Jamal , Nived Ola
Published: July 2015

Measuring lupus disease activity accurately remains a challenging and demanding task given the complex multi-system nature of lupus, an illness known for its variability between patients and within the same patient over time. Many have attempted to define what disease activity means and how it should be measured, and several instruments were devised for a standardized assessment of disease activity and outcome domains in clinical research. Several of these measuring tools have been able to detect clinical improvement and have demonstrated adequate reliability, validity, and sensitivity to change in observational studies, and some were found to be useful in randomized controlled trials. However, several failed clinical trials have confronted these metrics, as they were not intended for clinical trials. The Outcome Measures Rheumatology group and the US Food and Drug Administration have recommended using measures of disease activity, cumulative organ damage, health-related quality of life, and adverse events as outcomes of interest. Composite responder indices that determine disease global improvement, ensure no significant worsening in unaffected organ systems, and include a physician’s global assessment have been used in randomized clinical trials. Yet unmet therapeutic needs were further challenged by the complex content and psychometric information of the updated instruments, including increased administrative burden associated with demanding training and cost of instruments, and small effect size associated with responsiveness to patient concerns. Nevertheless, with the progress of novel targeted therapy, refining the disease activity metrics is essential. Selection of the disease activity endpoints which is a defining aspect of clinical trial design must be tailored to the outcome of interest and measured by a reliably rated scale characterized by minimal administrative burden. An optimal scale should be simple and practical and incorporate elements of patient concerns.
Pathophysiology of cutaneous lupus erythematosus
Authors: Achtman Jordan C , Werth Victoria P
Published: July 2015

The pathophysiology of cutaneous lupus erythematosus (CLE) encompasses the complex interactions between genetics, the environment, and cells and their products. Recent data have provided enhanced understanding of these interactions and the mechanism by which they cause disease. A number of candidate genes have been identified which increase the risk of developing CLE. Ultraviolet radiation, the predominant environmental exposure associated with CLE, appears to initiate CLE lesion formation by inducing apoptosis, precipitating autoantigen presentation, and promoting cellular production of specific cytokines. Autoantibodies are a well-known entity in CLE, but their exact role remains unclear. Finally, cells ranging from native skin cells to innate and adaptive immune cells produce cytokines and other molecules and play specific roles in lesion formation and perpetuation. Native skin cells implicated in CLE include keratinocytes and endothelial cells. Innate immune cells crucial to CLE pathophysiology include dendritic cells and neutrophils. The primary adaptive immune cells thought to be involved include Th1 cells, Th17 cells, cytotoxic T cells, and invariant natural killer T cells. Though the pathophysiology of CLE has yet to be fully characterized, current research provides direction for future research and therapies.
Sustained biologic-free and drug-free remission in rheumatoid arthritis, where are we now?
Authors: Nagy György , van Vollenhoven Ronald F
Published: July 2015

The advent of new medications and new treatment strategies for rheumatoid arthritis has made it possible to achieve remission in more patients than before. Furthermore, recent clinical trials and register studies suggest that some patients who initially required aggressive therapy may achieve biologic-free remission or even the ultimate goal of therapy, drug-free remission, resembling recovery. Here, we present a discursive review of the most important studies addressing these issues. Based on the overall results, it remains unclear if achieving biologic-free and drug-free remissions are primarily due to the natural course of the disease or to the early therapeutic intervention according to the ‘window of opportunity’ hypothesis. Although medication-free remission is only achievable in a small subset of patients, characterizing this patient cohort may provide important information about beneficial prognostic factors and the underlying mechanisms. In summary, in a subset of patients biologic-free and even drug-free remission can be achieved; pursuing these possibilities in practice may decrease the risk for long-term side effects and attenuate the economic burden of the disease.
Convergence theorems for finite family of a general class of multi-valued strictly pseudo-contractive mappings
Authors: Chidume Charles E , Okpala Mmaduabuchi E , Bello Abdulmalik U , Ndambomve Patrice
Published: July 2015

Let H be a real Hilbert space, K a nonempty subset of H, and $T:K\rightarrow \mathit{CB}(K)$
T
:
K
→
CB
(
K
)
a multi-valued mapping. Then T is called a generalizedk-strictly pseudo-contractive multi-valued mapping if there exists $k\in[0,1)$
k
∈
[
0
,
1
)
such that, for all $x,y\in D(T)$
x
,
y
∈
D
(
T
)
, we have $D^{2}(Tx,Ty)\leq\|x-y\|^{2}+kD^{2}(Ax,Ay)$

D
2

(
T
x
,
T
y
)
≤

∥
x
−
y
∥

2

+
k

D
2

(
A
x
,
A
y
)
, where $A:=I-T$
A
:
=
I
−
T
, and I is the identity operator on K. A Krasnoselskii-type algorithm is constructed and proved to be an approximate fixed point sequence for a common fixed point of a finite family of this class of maps. Furthermore, assuming existence, strong convergence to a common fixed point of the family is proved under appropriate additional assumptions.
Fixed point theorems for Ćirić type mapping and application to integral equation
Authors: Ume Jeong Sheok
Published: July 2015

In this paper, we introduce a new class of Ćirić type single-valued mapping with respect to u-distance and prove some fixed point theorems for this mapping. An example is given to show that our results are a proper extension of many well-known results. As an application, we establish the existence of a solution for an integral equation.
Rapid bone regeneration by
Escherichia coli
-derived recombinant human bone morphogenetic protein-2 loaded on a hydroxyapatite carrier in the rabbit calvarial defect model
Authors: Chung Chung-Hoon , Kim You-Kyoung , Lee Jung-Seok , Jung Ui-Won , Pang Eun-Kyoung , Choi Seong-Ho
Published: July 2015

Background

The aim of this study was to determine the osteoconductivity of hydroxyapatite particles (HAP) as a carrier for
Escherichia coli
-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2). Two 8-mm diameter bicortical calvarial defects were created in each of 20 rabbits. One of each pair of defects was randomly assigned to be filled with HAP only (HAP group) or ErhBMP-2 loaded HAP (ErhBMP-2/HAP group), while the other defect was left untreated (control group). The animals were killed after either 2 weeks (
n
 = 10) or 8 weeks (
n
 = 10) of healing, and histological, histomorphometric, and tomographic analyses were performed.

Results

All experimental sites showed uneventful healing during the postoperative healing period. In both histomorphometric and tomographic analyses, the new bone area or volume of the ErhBMP-2/HAP group was significantly greater than that of the HAP and control groups at 2 weeks (
p
 < 0.05). However, at 8 weeks, no significant difference in new bone area or volume was observed between the ErhBMP-2/HAP and HAP groups. The total augmented area or volume was not significantly different between the ErhBMP-2/HAP and HAP groups at 2 and 8 weeks.

Conclusions

Combining ErhBMP-2 with HAP could significantly promote rapid initial new bone formation. Moreover, HAP graft could increase new bone formation and space maintenance, therefore it might be one of the effective carriers of ErhBMP-2.
Paul Conduit
Authors: Conduit Paul
Published: July 2015

Paul Conduit was a research assistant in John Kilmartin's lab at the MRC/LMB in Cambridge, UK, before beginning his PhD in 2006 with Jordan Raff. In 2010 he moved with Jordan from the Gurdon Institute in Cambridge to the University of Oxford, where he continued his work as a postdoctoral fellow. Paul is now a Sir Henry Dale Wellcome Fellow at the University of Cambridge and has been a group leader at the Department of Zoology since April 2015. His lab studies microtubule nucleation from both centrosomes and from other microtubule-organising centres in the cell.
An Experimental Study of Stabilization of Trivalent Thallium by Natural Organic Matter
Authors: Watanabe Yusuke , Takahashi Yoshio
Published: July 2015

Stabilization of dissolved trivalent thallium, Tl(III), in water by complexation with humic acid and its analogue (poly(acrylic acid), PAA) was studied. Chromatographic analysis showed that Tl(III) was stabilized by the complexation, which allowed us to estimate the stability constant of Tl(III)–humate complex. Cyclic voltammograms of Tl showed that the redox potential of Tl(III)/Tl(I) redox couple in the presence of PAA was lower than that without PAA. These results suggest that Tl(III) can be present in natural water by the stabilization of Tl(III) rather than Tl(I) due to the formation of humate complex.
Complexes of the Noble Gases with H3O+: A Theoretical Investigation of Ng(H3O+) (Ng = He—Xe)
Authors: Borocci Stefano , Cecchi Patrizio , Giordani Maria , Grandinetti Felice
Published: July 2015

The geometries, harmonic vibrational frequencies, and binding energies (BEs) of the Ng(H3O+) complexes (Ng = He–Xe) were investigated at the coupled cluster level of theory, and their bonding situation was assayed by various methods of bonding analysis. The effects of Ng on H3O+ progressively increase from He to Xe, and only He can be regarded as an essentially “innocent” ligand. The BEs also increase in the same periodic order, and are by far dominated by the “noncovalent” ion-induced dipole interaction arising from the H3O+-induced polarization of Ng. For Ne, Ar, Kr, and Xe, this term has a larger contribution from the p orbital lying on the bond axis, and two smaller contributions from the p orbitals perpendicular to the bond axis. For the heaviest, Ar(H3O+), Kr(H3O+), and Xe(H3O+), the BE also has a “covalent” component, which is ascribed to the relatively-appreciable charge transfer from Ng to H3O+.
An Electrospray Ionization-Ion Mobility Spectrometer as Detector for High-Performance Liquid Chromatography
Authors: Zühlke Martin , Riebe Daniel , Beitz Toralf , Löhmannsröben Hans-Gerd , Zenichowski Karl , Diener Marc , Linscheid Michael W.
Published: July 2015

The application of electrospray ionization (ESI) ion mobility (IM) spectrometry on the detection end of a high-performance liquid chromatograph has been a subject of study for some time. So far, this method has been limited to low flow rates or has required splitting of the liquid flow. This work presents a novel concept of an ESI source facilitating the stable operation of the spectrometer at flow rates between 10 μL min−1 and 1500 μL min−1 without flow splitting, advancing the T-cylinder design developed by Kurnin and co-workers. Flow rates eight times faster than previously reported were achieved because of a more efficient dispersion of the liquid at increased electrospray voltages combined with nebulization by a sheath gas. Imaging revealed the spray operation to be in a rotationally symmetric multijet mode. The novel ESI-IM spectrometer tolerates high water contents (≤90%) and electrolyte concentrations up to 10 mM, meeting another condition required of high-performance liquid chromatography (HPLC) detectors. Limits of detection of 50 nM for promazine in the positive mode and 1 μM for 1,3-dinitrobenzene in the negative mode were established. Three mixtures of reduced complexity (five surfactants, four neuroleptics, and two isomers) were separated in the millisecond regime in stand-alone operation of the spectrometer. Separations of two more complex mixtures (five neuroleptics and 13 pesticides) demonstrate the application of the spectrometer as an HPLC detector. The examples illustrate the advantages of the spectrometer over the established diode array detector, in terms of additional IM separation of substances not fully separated in the retention time domain as well as identification of substances based on their characteristic IMs.
USE OF MARKOV`S SUCCESSIONS IN DISTRIBUTION OF TRAF-FIC STREAM
Authors: Веневитина  , Venevitina Svetlana , Зеликов  , Zelikov Vladimir , Уточкина  , Utochkina Elena , Зеликова  , Zelikova O.
Published: July 2015

For mathematic description of traffic stream use of mathematic apparatus, that is used in theory of probability for Markov`s random process. Use of Mar-kov`s successions allows to set a problem of determining the probability of find-ing the traffic stream in any condition, as well as beingwith the help of Kolmogo-rov`s equations finding the possibility of denial, the possibility of maintenance, as well as absolute carrying capacity of the system.
Problem of free oscillations CAR
Authors: Веневитина  , Venevitina Svetlana , Зенина  , Zenina V. , Малыхин  , Malykhin V
Published: July 2015

We solve the problem of free vertical oscillations of the car, taking place in parallel to the plane of symmetry. We find conditions under which the only pos-sible vertical oscillation, or only the angular oscillations around the center of gravity. We find conditions that reduce the possibility of resonance.
SPECIFIC FAILURE TRACTION EQUIPMENT OF ROLLING STOCK
Authors: Карпенко  , Karpenko Stanislav
Published: July 2015

The design of electric locomotives VL80S nodes developed in the 60s of XX century, can not ensure failure operation for a reserve maintenance periods are constantly increasing. The largest number of failures accounted for traction motors and electrical equipment. The proposed Article measures and technical solutions will significantly reduce the number of failures of these products.
Cultivating Disaster Donors Using Data Analytics
Authors: Ryzhov Ilya O. , Han Bin , Bradić Jelena
Published: July 2015

Nonprofit organizations use direct-mail marketing to cultivate one-time donors and convert them into recurring contributors. Cultivated donors generate much more revenue than new donors, but also lapse with time, making it important to steadily draw in new cultivations. The direct-mail budget is limited, but better-designed mailings can improve success rates without increasing costs. We propose an empirical model to analyze the effectiveness of several design approaches used in practice, based on a massive data set covering 8.6 million direct-mail communications with donors to the American Red Cross during 2009–2011. We find evidence that mailed appeals are more effective when they emphasize disaster preparedness and training efforts over post-disaster cleanup. Including small cards that affirm donors’ identity as Red Cross supporters is an effective strategy, whereas including gift items such as address labels is not. Finally, very recent acquisitions are more likely to respond to appeals that ask them to contribute an amount similar to their most recent donation, but this approach has an adverse effect on donors with a longer history. We show via simulation that a simple design strategy based on these insights has potential to improve success rates from 5.4% to 8.1%.

This paper was accepted by Serguei Netessine, operations management.
Las redes de alta velocidad en los programas de formación de educadores
Authors: Romo Guerrón José Luis
Published: July 2015

Con la llegada de RENATA a Colombia y específicamente a San Juan de Pasto, se abren oportunidades de mejoramiento en la formación profesional con la puesta en práctica de redes académicas y trabajo colaborativo que coadyuvan a la integración interinstitucional. Diagnosticar las condiciones en que están los programas de formación de educadores para acceder a estas oportunidades es esencial. Las visitas a las universidades que los ofrecen, las encuestas a los docentes que brindan sus servicios y el análisis de las categorías consideradas como válidas presentan un panorama desolador. Al final del proceso, se encuentra que es prioritario hacer una planeación estratégica y construir experiencias educativas e investigativas de enseñanza y aprendizaje con el uso de TIC en los programas de educación.
Desarrollo de una metodología para integrar las TIC (Tecnologías de la Información y la Comunicación) en las IE (Instituciones Educativas) de Montería
Authors: Soto Jiménez Jan Carlos , Franco Enzuncho María Lucía , Giraldo Cardozo Juan Carlos
Published: July 2015

En este artículo, se presenta la metodología GITICIE (Gestión e integración de las tecnologías de la Información y Comunicación en las Instituciones educativas), desarrollada a través de un proceso de investigación-acción llevado a cabo entre los años 2010-2012 con la participación de docentes del área de Tecnología e Informática de 14 instituciones educativas públicas de la ciudad de Montería-Colombia. La metodología está fundamentada en siete ejes TIC y plantea cinco momentos que inician con la concientización sobre las bondades de integrar las TIC; posteriormente desarrolla una caracterización de las necesidades institucionales, que fundamentan la Planeación de las Mejoras TIC, diseñadas e implementadas por las comunidades educativas, encargadas del seguimiento, valoración y ajustes a las acciones en forma repetitiva hasta lograr resultados óptimos. En las instituciones permeadas se observó transformación en la dinámica del proceso de integración TIC, obteniendo como resultados el desarrollo de proyectos institucionales de GITIC como ejes orientadores de la integración, dinamizados por grupos de gestión que los coordinan.
Estrategias de enseñanza y aprendizaje de la lectura y escritura en educación primaria
Authors: Pérez Ruíz Violeta del Carmen , La Cruz Zambrano Amílcar Ramón
Published: July 2015

Este artículo muestra los resultados de un estudio cuyo propósito fue analizar las estrategias de enseñanza y aprendizaje de la lectura y la escritura en Educación Primaria del Municipio Maracaibo del Estado Zulia en Venezuela. Sustentado en las teorías de González (2008), Mohammad (2006), Álvarez (2004), se enmarca en una investigación de tipo descriptivo, con un diseño no experimental transeccional de campo. Se utilizó la técnica de la encuesta, y como instrumento el cuestionario. La validez del instrumento se constató con la opinión de cinco expertos y su confiabilidad se obtuvo con el coeficiente de Alfa Cronbach, con un puntaje de 0.98. Entre las conclusiones obtenidas se puede mencionar que casi nunca se cumple con las estrategias metacognitivas de atención, comprensión, memorización, que el indicador repetición presenta debilidades, mientras que la organización y la elaboración son fortalezas en las estrategias de enseñanza y aprendizaje, por lo que se recomienda aplicar talleres para el personal docente que faciliten estrategias sobre lectura y escritura.
La deserción estudiantil UIS, una mirada desde la responsabilidad social universitaria
Authors: Zárate Rueda Ruth , Mantilla Pinilla Eduardo
Published: July 2015

La deserción estudiantil en las instituciones de educación superior se ha convertido en un problema social que aqueja a las poblaciones más vulnerables dentro de la estructura socioeconómica, limitando las posibilidades del desarrollo humano y, por ende, el desarrollo de una nación, debiendo ser abordada la problemática desde las políticas institucionales de educación superior en el marco de su Responsabilidad Social Universitaria –RSU– con la comunidad y el Estado. De ahí, la importancia del abordaje del tema de deserción UIS desde una mirada cuanti-cualitativa y en referencia a la RSU.
Construcción y validación de un instrumento para medir las competencias ciudadanas en estudiantes universitarios
Authors: Zambrano Ojeda Elizabeth , Fernández Candama Federico , Rivera Cisnero Antonio , Zapata Zapata Emperatriz
Published: July 2015

El objeto de esta investigación fue construir y validar un instrumento para medir las competencias ciudadanas en estudiantes universitarios. Se hizo la construcción del instrumento tomando como referencia las Pruebas Saber de Competencias Ciudadanas de los años 2003-2005 y los estándares de Competencias Ciudadanas del Ministerio de Educación Nacional (MEN) de la República de Colombia. Este instrumento se estructuró en cinco componentes distribuidos en conocimientos (ciudadanos) y competencias (comunicativas, emocionales, cognitivas e integradoras). Las competencias se subdividen en: ambientes democráticos, empatía, emociones, pensamiento crítico, consideración de consecuencias, y acciones y actitudes. Se evaluaron tres tipos de validez. Validez de contenido: haciendo uso de la bibliografía relacionada, la valoración de un par académico y las recomendaciones de los expertos en elaboración de cuestionarios; validez de constructo: utilizando el análisis factorial; y la validez de consistencia y confiabilidad: utilizando el método Alfa de Cronbach, el cual arrojó 0.75, un nivel de consistencia interna bueno.
О задаче Дирихле для эллиптического уравнения
Authors: Гущин Анатолий Константинович , Gushchin Anatolii Konstantinovich
Published: July 2015

Хорошо известно, что естественно возникающее из вариационных принципов и удобное в применении понятие обобщeнного решения из соболевского пространства $W_2^1$ задачи Дирихле для эллиптического уравнения второго порядка не является в буквальном смысле обобщением понятия классического решения: не любая непрерывная на границе области функция является следом функции из $W_2^1$. Обобщение обоих этих понятий было предложено в 1976 году Валентином Петровичем Михайловым, памяти которого посвящена настоящая работа. В определении Михайлова граничное значение решения берется из $L_2$; естественно обобщается это понятие и на случай граничной функции из $L_p$, $p > 1$. Впоследствии автором настоящей работы было доказано, что при выполнении не слишком обременительных условий такие решения обладают свойством $(n-1)$-мерной непрерывности. Это свойство аналогично классическому определению равномерной непрерывности, но вместо значения функции в точке следует рассматривать еe следы на мерах из специального класса, немного более узкого, чем класс мер Карлесона. След функции на мере является элементом пространства $L_p$ по этой мере. $(n-1)$-мерная непрерывность означает, что следы на мерах близки, если близки эти меры. Определение близости мер учитывает близость (в специальном смысле) их носителей, а расстояние между следами (они элементы различных пространств) вводится с помощью погружения в пространство функций удвоенного числа переменных. Свойство $(n-1)$-мерной непрерывности позволило дать другое, по форме весьма близкое к классическому определение решения - $(n-1)$-мерно непрерывное решение. Как и понятия классического и обобщeнного решений оно не требует условий гладкости границы рассматриваемой области. В отличие от случаев классического и обобщeнного решений задача Дирихле в постановке Михайлова и тем более с $(n-1)$-мерно непрерывным решением исследована недостаточно полно. Прежде всего это относится к условиям на правую часть уравнения, при которых задача Дирихле разрешима. В работе приведeн ряд новых результатов в этом направлении. Кроме того, обсуждаются условия на коэффициенты уравнения, границу ограниченной области, в которой рассматривается задача, и заданные граничные значения решений. При этом результаты о разрешимости и о граничном поведении решений сравниваются с аналогичными теоремами, относящимися к случаю классического и обобщeнного решений, обсуждаются некоторые возникающие при таком сравнении нерешeнные задачи.
Ультраметрическая диффузия в сильном центрально-симметричном поле
Authors: Сизова Ольга Михайловна , Sizova Olga Mikhailovna
Published: July 2015

Рассмотрен случайный процесс на границе конечного регулярного дерева, помещeнного во внешнее центрально-симметричное поле, относительно введeнной ультраметрики. Показана процедура сведения этой задачи к задаче меньшей размерности. Также рассматривается случай предельно сильного поля, который удаeтся решить аналитически. Приводятся решение для частного случая линейного роста иерархии барьеров переходов и оценка кинетики перехода в основное состояние.
Нелокальная задача для уравнения с частной производной дробного порядка
Authors: Репин Олег Александрович , Repin Oleg Aleksandrovich , Тарасенко Анна Валерьевна , Tarasenko Anna Valerievna
Published: July 2015

Для уравнения с частными производными смешанного типа (уравнение диффузии дробного порядка) в конечной области исследована нелокальная задача, краевое условие которой содержит линейную комбинацию обобщeнных операторов дробного интегро-дифференцирования от значений решения на характеристиках со значениями решения и его производной на линии вырождения.
Единственность решения задачи доказана с помощью модифицированного метода Трикоми, а существование решения эквивалентно редуцировано к вопросу разрешимости интегральных уравнений Фредгольма второго рода.
Interview with a Celebrity Cartographer: Jim Meacham
Authors: Tierney Lauren , Meacham Jim
Published: July 2015

James E. Meacham is a Senior Research Associate at the University of Oregon, and Executive Director and co-founder of the InfoGraphics Lab in the University’s Department of Geography. He received his MA in Geography from the UO in 1992, and has served as the president of NACIS. His interests include map and atlas design, and data visualization. He is a co-creator of the Atlas of Yellowstone (2012), Archaeology and Landscape in the Mongolian Altai: An Atlas (2010), and the Atlas of Oregon (2001). He teaches cartography courses at the University of Oregon. His current projects include the development of the Atlas of Wildlife Migration: Wyoming’s Ungulates.
Indien sehen und sterben. Die Indienreisen Alexanders des Großen in MS London Jews’ College no. 145
Authors: Bedeković Nataša
Published: July 2015

The journey to India is an intrinsic part of the Alexander romances. Once transferred to fabulous surroundings, his journey becomes a suitable foundation for discussing and questioning diverse ethical values and cultural models. The Hebrew Alexander romance in MS London Jews’ College no. 145 divides Alexander’s Indian conquest into three parts, which are all told in the same manner. In each section of the journey he gains different experiences as he crosses inaccessible territories and fights against marvellous and monstrous creatures. They change his view of the world and make him understand that he is mortal. Alexander comes to India as a conqueror of the world who aspires to immortality, he travels there as an explorer, getting acquainted with the habits and philosophies of foreign cultures, and returns to Babylon as a sovereign who has been confronted with his own mortality.
Die Rolle jüdischer Finanziers bei reichsstädtischen Expansionsbestrebungen im späten Mittelalter
Authors: Scholl Christian
Published: July 2015

This article deals with the role Jewish moneylenders played in the expansion policy of Imperial Cities in the Later Middle Ages. It focuses on the examples of Zurich , Bern and Ulm because it was in these cases that Jews made the most important contributions to the creation of urban territories. As will be shown, there were several ways by which city councils could make use of Jewish money to support their territorial ambitions: Unfortunately, one way of acquiring money for territorial expansion was the plundering of Jewish communities, which happened in Ulm in 1385, for example. Apart from that, the city councils could gain territorial profit from Jewish businessmen granting loans to noblemen who were endowed with landed property in the vicinity of the cities. When these nobles could not repay their loans to the Jews, they were forced to cede their territories to the city councils which, in return, repaid the noble’s loans to the Jewish moneylenders. Probably due to the high interests, the city councils themselves, however, hardly ever took out loans to finance territorial expansion directly.
Teacher’s and student’s competence beliefs according to scenario theory
Authors: Čerešník Michal
Published: July 2015

The article is connected with the problem of personal teacher’s and student’s competence, resp. saturation of need for competence, which reflects our desire to sense that our activity, abilities and effort are crucial for our impression that we influence our environment, for our feeling that we are respectable people. We are interested mainly in the problem of perceived control in the context of specific scenario teacher-student.
Measuring of educational service quality (focused on universities)
Authors: Kamoďa Ján
Published: July 2015

This paper deals with common problems in the process of education at the university level. It focuses on the quality of education process. The aim of this paper is to determine the principal criteria of the quality measurement of the education service.
Rice as food and medication in ancient and Byzantine medical literature
Authors: Kokoszko Maciej , Jagusiak Krzysztof , Rzeźnicka Zofia
Published: July 2015

The article discusses rice (ὄρυζα) on the basis of medical writings compiled between the first and seventh centuries, and consists of four parts. The first tries to assess the spread of rice in the Greco-Roman agriculture. The results of the analysis support conclusions present in the literature and confirm the fact that rice was never popular in the Mediterranean in antiquity and later during the period of early and middle Byzantium. A gradual change in its status appeared along with the Arab agricultural revolution. The second chapter of the study is devoted to dietetic characterizations of rice and enlists features attributed to it, which were consistently made use of in medical procedures. The third part of the study tries to retrieve from medical writings main culinary guidelines concerning rice. The authors conclude that the cereal usually was the basis for preparation of cooked dishes and was hardly ever used in baking. The fourth chapter enumerates medical procedures which included rice (cure of intestinal problems, hemorrhages, other ailments resulting in excessive excretion of fluids of the body, gout etc.).
The “king of Francia” in De cerimoniis II, 48
Authors: Komatina Predrag
Published: July 2015

In what is known as the List of addresses to the foreign rulers of De cerimoniis aulae Byzantinae (II, 48) by Constantine VII Porphyrogenitus (913-959), there is an address to a ruler called “king of Francia”. This paper is devoted to an attempt to find the answer to the question of who this “king of Francia” might have been. Judging from the fact that in that address both the Roman emperors and the ruler it concerns are given very exalted epithets, the address to the “king of Francia” designates a ruler who was, for various reasons, considered by the imperial chancery more distinguished and more important than other rulers of Western Europe. Current opinion holds that the ruler in question was Otto I and that the address reflects the then prevailing view in Constantinople of Otto as the most serious candidate for the crown of the Western Empire. According to the research of Constantine Zuckerman, the List of addresses, along with other “diplomatic chapters” of the Book of Ceremonies, was composed in 946. In September 944 the marriage was concluded between Romanus II, the son of Constantine VII Porphyrogenitus, and Bertha, natural daughter of Hugh, then king of Italy. Describing that event, contemporary Byzantine writers refer to Hugh as the “king of Francia”. This paper examines the possibility of linking this “king of Francia” with the one in the List of addresses, on the basis of information concerning King Hugh in another work by emperor Constantine VII Porphyrogenitus - De administrando imperio.
Kaukasische Aristokraten auf byzantinischer Karriereleiter
Authors: Wassiliou-Seibt Alexandra-Kyriaki
Published: July 2015

The family Aspietes from the (Armeno-Iberian) Pakourianos-Clan has as ancestor the Aspietes (here it is a first name!), who was one of the most important generals of emperor Alexios I Komnenos. Anna Komnene speaks highly of his military virtues and capacity during the war against Robert Guiscard (1081), but disparages him as commander in Cilicia and Western Syria shortly after the First Crusade. There is little doubt that this Aspietes is identical with the Aspietes Pakourianos attested on seals as κουροπαλάτης and πρωτονωβελλίσιμος. One of his sons married in the 12th century an unknown daughter of Andronikos Komnenos σεβαστοκράτωρ as we learn from the metrical legend of a seal. They became the parents of three or four sons who used the first name of the ancestor Aspietes as family name to specify their branchwithin the Clan of the Pakourianoi.
On the truncated operator trigonometric moment problem
Authors: Zagorodnyuk Sergey
Published: July 2015

In this paper we study the truncated operator trigonometric moment problem. All solutions of the moment problem are described by a Nevanlinna-type parameterization. In the case of moments acting in a separable Hilbert space, the matrices of the operator coefficients in the Nevanlinna-type formula are calculated by the prescribed moments. Conditions for the determinacy of the moment problem are given, as well.
Extensions of symmetric operators I: The inner characteristic function case
Authors: Martin R.T.W.
Published: July 2015

Given a symmetric linear transformation on a Hilbert space, a natural problem to consider is the characterization of its set of symmetric extensions. This problem is equivalent to the study of the partial isometric extensions of a fixed partial isometry. We provide a new function theoretic characterization of the set of all self-adjoint extensions of any symmetric linear transformation B with finite equal indices and inner Livšic characteristic function θ
Interesting faunistic records of meniscus midges (Diptera: Dixidae) from Slovakia
Authors: Oboňa Jozef , Manko Peter , Matúšová Zuzana , Novikmec Milan , Svitok Marek
Published: July 2015

Records of meniscus midges (Diptera: Dixidae) are reported from lotic and lentic water bodies with of Slovakia. Midges were sampled during specifically aimed research of ponds (project BIOPOND) or during field works related to various studies of running waters. In total, occurrence of 3 species of genus Dixa and 1 species of genus Dixella are presented and shortly discussed. Record of Dixa dilatata Strobl, 1900 on the basis of adult specimen is reported from Slovakia for the first time.
Sensitivity of Czech Commercial Banks to a Run on Banks
Authors: Klepková Vodová Pavla
Published: July 2015

The aim of this paper is to thoroughly evaluate the sensitivity of Czech commercial banks to a run on banks. Our sample includes a significant part of the Czech banking sector in the period 2006-2013. We use three liquidity ratios that we stress via a stress scenario simulating a run on banks accompanied by a 20% withdrawal rate of deposits.We measure the impact of the scenario by the relative changes of these ratios. The results show that, in spite of a decrease in liquidity, most Czech banks would be able to finance such a scenario. The financial crisis influenced bank sensitivity to a run, but with a significant time lag. The severity of the impact of the bank run increases with the size of the bank; large banks are the most vulnerable. The resilience of banks is also determined by their strategy for liquidity risk management.