bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulación del temple en bolas de desgaste de acero
Authors: Zapata-Hernández Oscar , Reyes Luis A. , Camurri Carlos , Carrasco Claudia , Garza-Montes-de-Oca Nelson F. , Colás Rafael
Published: September 2015

Las transformaciones de fase en aceros de alto carbono durante su temple y un posterior periodo de estabilización fueron modelizadas por medio del uso de paquetes computacionales basados en el método del elemento finito y de la transformación cinética de los aceros. El modelo se usó para predecir los cambios de temperatura y microestructura que se presentan en bolas de dos diferentes tamaños empleadas en estaciones de molienda de minerales. Se encontró una buena correlación entre las temperaturas medidas mediante la inserción de termopares y aquellas predichas por el modelo una vez que se modificó la conductividad térmica del acero en el intervalo mixto de fases. La predicción de las transformaciones de fase se confirmó a través del análisis metalográfico.
Online Prevention and Early Intervention in the Field of Psychiatry Using Gamification in Internet Interventions
Authors: Hanusová Jana , Štěpánková Tereza , Tomanová Jana , Dočkalová Simona , Papežová Hana
Published: September 2015

Many individuals, who suffer from mental disorders, seek professional help late or not at all, which increases the risk of chronification and reduces the chance of recovery. Insufficient services in the place of living, lack of information, shame and fear of stigmatization often prevent seeking help. The potential to reduce these barriers can be seen in anonymous Internet interventions, many of them were proved to be effective. The main problem reported across the studies is low actual use of the programs when disseminated to the public. Gamification and serious computer games is seen to have the potential to increase user satisfaction with Internet interventions, motivation to use the programs and thus affect possible outcomes. We show examples of games targeting mental health improvement and awareness that have been scientifically evaluated. We also provide our experience with the development of a game targeting prevention and early intervention for eating disorders, disseminated in the Czech Republic together with the European prevention program ProYouth.
Research of Behaviour of Inorganic Matrix Composites Exposed to Extreme Temperatures
Authors: Dufka Ámos , Melichar Tomáš
Published: September 2015

The article is focused on complex analysis of the principles of degradation of composites based on alkali-activated materials exposed to extreme temperatures (max. temperature 1200 degree of Celsius). Thanks to specific properties these materials show a remarkable potential for the special application, for example for construction with high risk of fire etc. The effect of high temperatures shall be tested not only at such extreme levels but also at gradually increasing temperatures. The temperature effects shall be evaluated not only in of changes physic-mechanical parameters but also the physic-chemical determinations.
Effect of Polymer Admixtures on Mechanical Properties of Alkali-Activated Slag Mortars
Authors: Mikhailova Olesia , Rovnaník Pavel
Published: September 2015

Alkali-activated slag (AAS) binders have lower environmental impact due to its production process, but also have disadvantages as an increased shrinkage followed by formation of microcracks. The effect of polymer admixtures based on vinyl acetate, ethylene and acrylic acid ester, methyl metacrylate and different types of polyethylene glycol (PEG) and polypropylene glycol (PPG) on properties of alkali-activated slag concrete was studied. Admixtures used for mortars were tested to improve shrinkage, workability and compressive strength, flexural strength. The analysis also showed the effect of the admixtures on microstructure of the alkali-activated slag pastes and mortars.
Effect of Different Cooling Conditions on the Properties of Composite Materials with Cement Based Matrix
Authors: Melichar Tomáš , Bydžovský Jiří
Published: September 2015

This paper is focused on the study of the parameters of developed composite materials with a polymer-cement matrix modified by raw materials from alternative resources. Test specimens were gradually exposed to extreme temperatures and subsequently cooled in a controlled manner under different conditions. Heat stress was applied up to 1,000°C. The effects of controlled gradual or shock water cooling were monitored on the basis of physical and mechanical properties. The by-products currently produced by the power and metallurgical industries were used as substitution components for matrix modification.
Influence of the Fly Ash Character on Quality of Artificial Aggregate
Authors: Černý Vit
Published: September 2015

In a world is of ever-increasing pressure on the use of fly ash in building materials. Despite these efforts the majority of produced energy by-products end up as reclamation material and only small part as high-quality materials. Technology of sintered artificial aggregate is fully based on the fly ashes and allows processing a high percentage of this raw material. The work is devoted to assessing the impact of fly ash character on the quality artificial aggregate. There were selected three fly ashes from high-temperature combustion technology and two from the FBC combustion. The results clearly show that the FBC ashes are not too useful for sintered aggregate technology. For fly ashes is determined primarily by their fineness and the amount of amorphous silica phase.
The Use of Simulation Models for Complex Description of Permittivity of Building Materials
Authors: Kusák Ivo , Lunak Miroslav , Carbol Ladislav
Published: September 2015

Distribution function of relaxation time mathematically describes frequency dependence of the complex permittivity. Empirical function describing the complex permittivity in the frequency domain needs to be broken down to real and imaginary part, and thus separated. The permittivity is a function of the frequency of the electric field and describes behavior of technical dielectric in an alternating electric field. In this case the dielectric is a building material. The paper describes application of simulation models with variable distribution parameters and relaxation time.
Possibilities of Aerated Concrete Remediation through the Usage of Injection Screens
Authors: Melichar Jindřich , Drochytka Rostislav , Dohnálek Pavel
Published: September 2015

Usage of hydroinsulating gels in order to create injection screens in various building materials to deny rising wetness is nowadays one of the most widespread methods of remediation of damaged structures. One of the biggest advantages of this method are its low impact on the building statics, relatively quick and easy application and low final cost. The main focus of this article is observation effectiveness and final functionality of various types of hydroinsulating gels in samples of aerated concrete.
Correct Choice of Maximum Length Sequence in Nondestructive Testing
Authors: Carbol Ladislav , Martinek Jan , Štefková Daniela
Published: September 2015

Maximum Length Sequence has great potential as testing signal in non-destructive testing. Because its autocorrelation is almost a delta function, the sequence can be used for speed of sound assessment. Resulting Impulse response contains very similar data as Impact-echo. Unlike Impact-echo, where strike energy is limited by nonlinear effects, Maximum Length Sequence can deliver virtually unlimited energy over time. Length of the sequence and also signal generation rate is a curtail choice in order to achieve the best results.
Comparison of Bond Behaviour between Reinforcement and UHPC and Ordinary Concrete in Extreme Conditions
Authors: Citek David , Mandlík Tomáš , Kolisko Jiří , Rehacek Stanislav
Published: September 2015

The UHPC (Ultra High Performance Concrete) is a promising material suitable for application in special structures. However, the knowledge on performance of this relatively new material is rather limited. The exceptional mechanical properties of UHPC allow for a modification of the design rules, which are applicable in ordinary or high strength concrete. The research executed already in the Czech Republic showed that the anchorage length of ordinary and prestressing steel may be significantly shorter than that which is usually required in code specifications. This paper deals in more detail with impact of thermal stress on bond of prestressing strands and UHPC. Samples were subjected to the cycling heat/frost device and effect of a number of cycles on final bond behaviour of both UHPC and ordinary concrete were investigated. The article describes differences between ordinary concrete and UHPC.
Hygrothermal Behaviour of Newly Developed Thermal Insulation Plasters with Natural Fibres
Authors: Hroudová Jitka , Sedlmajer Martin , Zach Jiří
Published: September 2015

Throughout history, natural fibres have been known to be added in plaster mixes in order in order to prevent the formation of microcracks. These plasters can still be encountered during reconstruction of historical buildings but are used in new buildings as well. The goal of this research was to develop new, low energy cost thermal insulation plasters with natural fibres and afterwards examine and analyse their hygrothermal transport. Given their presumable application in the rehabilitation of old and historical buildings which often suffer from damp and salt attack, the research was also focused on the examination of their capillary activity.
Experimental Tests of White UHPC Plates Reinforced by PVA Fibres and Textile Glass Reinforcement
Authors: Bittner Tomáš , Tej Petr , Vokáč Miroslav , Bouška Petr , Nenadálová Šárka
Published: September 2015

The paper is about a research focused on a development of thin slabs made from white UHPC. These slabs are reinforced by scattered PVA fibres and textile glass reinforcement in form of 2D net. The aim of the experiment is the development of tin slabs that can be used as facade or roof panels. The course of the experimental tests of these slabs and its correspondence with the numeric analysis made with ATHENA software is in the paper. Three slab specimens with size of 750 x 125 x 15 mm were tested in four-point bending. The white UHPC matrix was reinforced by the scattered PVA fibres and the 2D textile glass reinforcement with mesh 20 x 20 mm. The used 2D reinforcement was coated against alkali conditions, so called AR - Glass with 2400 TEX fineness. The reinforcement was placed and fixed near the lower surface of the slabs. The course of the tests was continually monitored by an automatic measuring unit where especially the acting force, the deformation in the middle of the span, the deformation in the supports and the progressive formation and development of cracks were detected. The numeric model was created in 3D surroundings of Gid 2011 program and then converted into ATENA software.
Diferencias territoriales en las percepciones políticas en Chile. Una aproximación operacional a la escala nacional y regional
Authors: Delamaza Gonzalo , Thayer Correa Luis Eduardo , Gaete José Manuel
Published: September 2015

La investigación que se presenta tiene por objetivo visibilizar algunas diferencias significativas en distintas escalas territoriales, en cuanto a percepciones políticas relevantes para la gobernanza democrática y la constitución de la esfera pública, como adhesión a la democracia y confianza interpersonal y hacia las instituciones, entre otros. Para ello se comparan resultados de encuestas nacionales con datos del Barómetro Regional 2013, una encuesta aplicada a muestras representativas de las regiones de Los Ríos, Los Lagos y Bío Bío. El análisis muestra que las opiniones y percepciones regionalizadas difieren significativamente, no solo respecto del conjunto del país, sino también entre las mismas regiones. Con ello se deja en evidencia que uno de los problemas de la esfera pública nacional es que aquello que se presenta como el “nosotros” –la comunidad política- estaría escindido de las experiencias y las subjetividades que ese “nosotros” pretende representar. Y que la incorporación de la diferenciación regional permite un enfoque más preciso sobre la gobernanza democrática.
Terrorismo y contraterrorismo en Colombia
Authors: Álvarez Rubio Ariel
Published: September 2015

El presente artículo da cuenta de un análisis referido al terrorismo y a las acciones contraterroristas evidenciadas en Colombia, con énfasis en el período comprendido entre el fin de la guerra fría y el año 2013. Este estudio abarca tanto la tipología emergente del terrorismo presente en Colombia, como también las políticas de Estado, establecidas para enfrentar, en el mismo lapso de tiempo, las amenazas impuestas por el terrorismo. Los antecedentes evaluados, permiten inferir el grado de responsabilidad histórica que le compete tanto a las Fuerzas Armadas Revolucionarias de Colombia – Ejército del Pueblo (FARC-EP) como al propio Estado, respecto del grave estado de violencia en que se encuentra sumida la sociedad colombiana.
Molecular Dynamics Approach in the Comparison of Wild-Type and Mutant Paraoxonase-1 Apoenzyme Form
Authors: Amine Khadija , Miri Lamia , Naimi Adil , Saile Rachid , Kharrim Abderrahmane El , Mikou Afaf , Kettani Anass
Published: September 2015

There is some evidence linking the mammalian paraoxonase-1 (PON1) loops (L1 and L2) to an increased flexibility and reactivity of its active site with potential substrates. The aim of this work is to study the structural, dynamical, and functional effects of the most flexible regions close to the active site and to determine the impact of mutations on the protein. For both models, wild-type (PON1wild) and PON1 mutant (PON1mut) models, the L1 loop and Q/R and L/M mutations were constructed using MODELLER software. Molecular dynamics simulations of 20 ns at 300 K on fully modeled PON1wild and PON1mut apoenzyme have been done. Detailed analyses of the root-mean-square deviation and fluctuations, H-bonding pattern, and torsion angles have been performed. The PON1wild results were then compared with those obtained for the PON1mut. Our results show that the active site in the wild-type structure is characterized by two distinct movements of opened and closed conformations of the L1 and L2 loops. The alternating and repetitive movement of loops at specific times is consistent with the presence of 11 defined hydrogen bonds. In the PON1mut, these open-closed movements are therefore totally influenced and repressed by the Q/R and L/M mutations. In fact, these mutations seem to impact the PON1mut active site by directly reducing the catalytic core flexibility, while maintaining a significant mobility of the switch regions delineated by the loops surrounding the active site. The impact of the studied mutations on structure and dynamics proprieties of the protein may subsequently contribute to the loss of both flexibility and activity of the PON1 enzyme.
Directed Differentiation of Pluripotent Stem Cells into Kidney
Authors: Morizane Ryuji , Lam Albert Q.
Published: September 2015

Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), represent an ideal substrate for regenerating kidney cells and tissue lost through injury and disease. Recent studies have demonstrated the ability to differentiate PSCs into populations of nephron progenitor cells that can organize into kidney epithelial structures in three-dimensional contexts. While these findings are highly encouraging, further studies need to be performed to improve the efficiency and specificity of kidney differentiation. The identification of specific markers of the differentiation process is critical to the development of protocols that effectively recapitulate nephrogenesis in vitro. In this review, we summarize the current studies describing the differentiation of ESCs and iPSCs into cells of the kidney lineage. We also present an analysis of the markers relevant to the stages of kidney development and differentiation and propose a new roadmap for the directed differentiation of PSCs into nephron progenitor cells of the metanephric mesenchyme.
“Now I Can Do Better”: A Study of Obese Women's Experiences following a Nonprescriptive Nutritional Intervention
Authors: Ulian Mariana D. , Gualano Bruno , Benatti Fabiana B. , de Campos-Ferraz Patricia L. , Roble Odilon J. , Modesto Bruno T. , Brito Bruna C. , Murakawa Karina A. , Torre Mariana D. , Tritto Aline C.C. , Unsain Ramiro F. , de Sato Priscila M. , Scagliusi Fernanda B.
Published: September 2015

The present study analyzed obese women's experiences following a nonprescriptive nutritional intervention, implemented through a 1-year program based on the Health at Every Size® philosophy. We employed an action research method and conducted three focus groups during the intervention. We identified five interpretative axes across the focus groups, as follows: conflicts and perceptions; gaining motivation, perspective, and positioning; becoming autonomous eaters; acquiring tools; and the meetings between the nutritional therapist and participant. Our findings revealed varying levels of readiness among participants in adapting to the intervention and varying valuations of achievements related to eating and health, independent of body-weight changes. Participants reported benefiting from and expressed approval of the intervention. Participants reported positive behavioral and attitudinal changes to their diet and improvements to diet quality, diet structure, and consumption. Finally, participants seemed to show increased autonomy concerning diet and indicated increased confidence, comfort, flexibility, and positivity of attitude regarding eating.
Expression Divergence of Duplicate Genes in the Protein Kinase Superfamily in Pacific Oyster
Authors: Gao Dahai , Ko Dennis C. , Tian Xinmin , Yang Guang , Wang Liuyang
Published: September 2015

Gene duplication has been proposed to serve as the engine of evolutionary innovation. It is well recognized that eukaryotic genomes contain a large number of duplicated genes that evolve new functions or expression patterns. However, in mollusks, the evolutionary mechanisms underlying the divergence and the functional maintenance of duplicate genes remain little understood. In the present study, we performed a comprehensive analysis of duplicate genes in the protein kinase superfamily using whole genome and transcriptome data for the Pacific oyster. A total of 64 duplicated gene pairs were identified based on a phylogenetic approach and the reciprocal best BLAST method. By analyzing gene expression from RNA-seq data from 69 different developmental and stimuli-induced conditions (nine tissues, 38 developmental stages, eight dry treatments, seven heat treatments, and seven salty treatments), we found that expression patterns were significantly correlated for a number of duplicate gene pairs, suggesting the conservation of regulatory mechanisms following divergence. Our analysis also identified a subset of duplicate gene pairs with very high expression divergence, indicating that these gene pairs may have been subjected to transcriptional subfunctionalization or neofunctionalization after the initial duplication events. Further analysis revealed a significant correlation between expression and sequence divergence (as revealed by synonymous or nonsynonymous substitution rates) under certain conditions. Taken together, these results provide evidence for duplicate gene sequence and expression divergence in the Pacific oyster, accompanying its adaptation to harsh environments. Our results provide new insights into the evolution of duplicate genes and their expression levels in the Pacific oyster.
PVFMM: A Parallel Kernel Independent FMM for Particle and Volume Potentials
Authors: Malhotra Dhairya , Biros George
Published: September 2015

We describe our implementation of a parallel fast multipole method for evaluating potentials for discrete and continuous source distributions. The first requires summation over the source points and the second requiring integration over a continuous source density. Both problems require (N2) complexity when computed directly; however, can be accelerated to (N) time using FMM. In our PVFMM software library, we use kernel independent FMM and this allows us to compute potentials for a wide range of elliptic kernels. Our method is high order, adaptive and scalable. In this paper, we discuss several algorithmic improvements and performance optimizations including cache locality, vectorization, shared memory parallelism and use of coprocessors. Our distributed memory implementation uses space-filling curve for partitioning data and a hypercube communication scheme. We present convergence results for Laplace, Stokes and Helmholtz (low wavenumber) kernels for both particle and volume FMM. We measure efficiency of our method in terms of CPU cycles per unknown for different accuracies and different kernels. We also demonstrate scalability of our implementation up to several thousand processor cores on the Stampede platform at the Texas Advanced Computing Center.
Airborne measurements of new particle formation in the free troposphere above the Mediterranean Sea during the HYMEX campaign
Authors: Rose C. , Sellegri K. , Freney E. , Dupuy R. , Colomb A. , Pichon J.-M. , Ribeiro M. , Bourianne T. , Burnet F. , Schwarzenboeck A.
Published: September 2015

Abstract. While atmospheric new particle formation (NPF) has been observed in various environments and was found to contribute significantly to the total aerosol particle concentration, the production of new particles over open seas is poorly documented in the literature. Nucleation events were detected and analysed over the Mediterranean Sea using two condensation particle counters and a scanning mobility particle sizer on board the ATR-42 research aircraft during flights conducted between 11 September and 4 November 2012 in the framework of the HYMEX (HYdrological cycle in Mediterranean EXperiment) project. The main purpose of the present work was to characterize the spatial extent of the NPF process, both horizontally and vertically. Our findings show that nucleation is occurring over large areas above the Mediterranean Sea in all air mass types. Maximum concentrations of particles in the size range 5–10 nm (N5–10) do not systematically coincide with lower fetches (time spent by the air mass over the sea before sampling), and significant N5–10 values are found for fetches between 0 and 60 h depending on the air mass type. These observations suggest that nucleation events could be more influenced by local precursors originating from emission processes occurring above the sea, rather than linked to synoptic history. Vertical soundings were performed, giving the opportunity to examine profiles of the N5–10 concentration and to analyse the vertical extent of NPF. Our observations demonstrate that the process could be favoured above 1000 m, i.e. frequently in the free troposphere, and more especially between 2000 and 3000 m, where the NPF frequency is close to 50 %. This vertical distribution of NPF might be favoured by the gradients of several atmospheric parameters, together with the mixing of two air parcels, which could also explain the occurrence of the process at preferential altitudes. In addition, increased condensation sinks collocated with high concentrations of small particles suggest the occurrence of NPF events promoted by inputs from the boundary layer, most probably associated with convective clouds and their outflow. After their formation, particles slowly grow at higher altitudes to diameters of at least 30 nm while not being greatly depleted or affected by coagulation. Our analysis of the particle size distributions suggests that particle growth could decrease with increasing altitude.
Interannual variability of upper tropospheric and lower stratospheric (UTLS) region over Ganges–Brahmaputra–Meghna basin based on COSMIC GNSS RO data
Authors:   Khandu, Awange J. , Forootan E.
Published: September 2015

Abstract. Poor reliability of radiosonde observational networks across South Asia imposes serious challenges in understanding climate variability and thermodynamic structure of the upper-tropospheric and lower-stratospheric (UTLS) region. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission launched in April 2006 have overcome many observational limitations that are inherent in conventional atmospheric sounding instruments. This study investigated the interannual variability of the UTLS region over the Ganges–Brahmaputra–Meghna (GBM) basin based on COSMIC radio occultation (RO) data from August 2006 to December 2013. Detailed comparisons were also made with various different radiosonde types and Numerical Weather Prediction (NWP) products. The results indicated that Indian Meteorological Department (IMD) radiosondes performed poorly despite upgrading to newer techniques. ShangE (of China) sonde showed the best agreement with COSMIC RO data with a mean temperature difference of −0.06 °C and a standard deviation of 1.44 °C while the older version (ShangM) indicated a cold bias of 0.61 °C in the UTLS region. The inter-annual variability of temperature in the UTLS region based on COSMIC RO data indicated a clear pattern of El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) while the stratospheric temperature anomalies reflected all three major Sudden Stratospheric Warming (SSW) events since 2007. The mean tropopause temperature varied from −70 to −80 °C, with an average height of about 15.5 to 16.3 km from winter to summer, indicating a pronounced annual cycle. The annual amplitudes of tropopause were found to be in the order of 0–6 °C and 0–1.5 km from tropical south to subtropical north. The anomalies of tropopause temperature and height exhibited the patterns of ENSO and IOD exceptionally well with a correlation of 0.65 and −0.52, respectively. The temperature data from Modern-Era Retrospective Analysis for Research Application (MERRA) agreed very well with COSMIC RO data.
Computation of vertically averaged velocities in irregular sections of straight channels
Authors: Spada E. , Tucciarelli T. , Sinagra M. , Sammartano V. , Corato G.
Published: September 2015

Abstract. Two new methods for vertically averaged velocity computation are presented, validated and compared with other available formulas. The first method derives from the well-known Huthoff algorithm, which is first shown to be dependent on the way the river cross section is discretized into several subsections. The second method assumes the vertically averaged longitudinal velocity to be a function only of the friction factor and of the so-called "local hydraulic radius", computed as the ratio between the integral of the elementary areas around a given vertical and the integral of the elementary solid boundaries around the same vertical. Both integrals are weighted with a linear shape function equal to zero at a distance from the integration variable which is proportional to the water depth according to an empirical coefficient β. Both formulas are validated against (1) laboratory experimental data, (2) discharge hydrographs measured in a real site, where the friction factor is estimated from an unsteady-state analysis of water levels recorded in two different river cross sections, and (3) the 3-D solution obtained using the commercial ANSYS CFX code, computing the steady-state uniform flow in a cross section of the Alzette River.
Glacier dynamics over the last quarter of a century at Jakobshavn Isbræ
Authors: Muresan I. S. , Khan S. A. , Aschwanden A. , Khroulev C. , Van Dam T. , Bamber J. , van den Broeke M. R. , Wouters B. , Kuipers Munneke P. , Kjær K. H.
Published: September 2015

Abstract. Observations over the past two decades show substantial ice loss associated with the speedup of marine terminating glaciers in Greenland. Here we use a regional 3-D outlet glacier model to simulate the behaviour of Jakobshavn Isbræ (JI) located in west Greenland. Using atmospheric and oceanic forcing we tune our model to reproduce the observed frontal changes of JI during 1990–2014. We identify two major accelerations. The first occurs in 1998, and is triggered by moderate thinning prior to 1998. The second acceleration, which starts in 2003 and peaks in summer 2004, is triggered by the final breakup of the floating tongue, which generates a reduction in buttressing at the JI terminus. This results in further thinning, and as the slope steepens inland, sustained high velocities have been observed at JI over the last decade. As opposed to other regions on the Greenland Ice Sheet (GrIS), where dynamically induced mass loss has slowed down over recent years, both modelled and observed results for JI suggest a continuation of the acceleration in mass loss. Further, we find that our model is not able to capture the 2012 peak in the observed velocities. Our analysis suggests that the 2012 acceleration of JI is likely the result of an exceptionally long melt season dominated by extreme melt events. Considering that such extreme surface melt events are expected to intensify in the future, our findings suggest that the 21st century projections of the GrIS mass loss and the future sea level rise may be larger than predicted by existing modelling results.
The Role of Error Analysis in Teaching and Learning of Second and Foreign Language
Authors: Jabeen Agsa , Kazemian Bahram , Shahbaz Mustafai Muhammad
Published: September 2015

The aim of this paper is to investigate errors made by second and foreign language (L2) learners so as to understand the strategies and techniques used in the process of second and foreign language learning. Error analysis is a very important area of applied linguistics as well as of second and foreign language learning. It is also a systematic method to analyze learners' errors. Errors are not always bad, rather they are crucial parts and aspects in the process of learning a language. They may provide insights into the complicated processes of language development as well as a systematic way for identifying, describing and explaining students' errors. Errors may also help to better understand the process of second and foreign language acquisition. This study tries to investigate why Pakistani ESL and Iranian EFL learners fail to produce grammatically correct sentences in English, in spite of having English as a compulsory subject at all levels in their learning institutions and schools. What are the reasons for their poor English written performance? In the present study, the writing assignments of university students as well as intermediate English learners were analyzed for the purpose of error analysis. Results of the analysis suggest that students lack grammatical accuracy in their writing and are not sure of the grammatical rules that may apply in their writing in English. The study concludes that they are highly influenced by the rules of their first language (L1).
Relating Maslow’s Hierarchy of Needs with Employee Turnover and Retention: Case Study of Local Telco
Authors: Hanif Ayesha , Khalid Wajiha , Khan Tahir Nawaz
Published: September 2015

Purpose: In this case study, we investigate the frequency and reasons for the junior employees’ turnover problems being faced by a growing Telco in Pakistan. Having identified the root causes, creative HR people practices have been suggested as solutions for retaining valuable talent. Methodology: A survey questionnaire was administered among the staff of the company under study to identify their needs satisfaction level and then asked them to rate factors instrumental for retaining high performing talent. A Multi-point Rating Scale (1-5 and 1-7) was used for the 33 items. Findings: The results explore which employee retention measures can be taken so as to improve employee job satisfaction, loyalty and productivity. The trend points along dimensions of financial benefits, improved work environment and growth opportunities. Practical Implication: On broader platform, we can generalize the employee retention factors ranking to other Telco/IT companies operating in the hyper-inflated environment of Pakistan.   Value: In many local growing organizations, effort and finance is not invested to determine Employee Satisfaction Index on an annual basis. This study will serve the purpose of preliminary survey in this regard for this company in addition to providing insight into common Pakistani lower-cadre employee needs.  Keywords: Employee Turnover, Employee Retention, Employee Satisfaction, Pakistan
Toward Enhancing Police-Community Relations in Nigeria: Problems and Prospects
Authors: Madaki Maikano , Kurfi Mustapha Hashim
Published: September 2015

This paper examines the existing relationship between the police and members of the public in Nigeria, highlighting the various problems endemic in both parties (the police and the public). The paper provides the essential pragmatic means of further enhancing this relationship for a better and peaceful society through the principles of community policing. The authors take a multi-dimensional approach to the police public relationship (P-PR) in Nigeria positing thatprimarily, there are structural, organizational, and attitudinal factors that led to the deteriorating nature of the P-PR in Nigeria. The paper posits that co-operation between the police and the public is a prerequisite for the success of any law enforcement agency, notably the police as well as a better, peaceful, and harmonious society. The police alone cannot achieve this without support from the members of the public whom they serve. For that kind of good working condition to be created, the police need to be polite, friendly, approachable, honest, law abiding and demonstrate high sense of responsibility in dealing with members of the public and in discharging their duties. On the other hand, the public must understand that maintaining law and order is a collective responsibility between the parties and should do everything possible to assist the police in protecting lives and property. Good and objective partnership between the community and the police will help bring positive response to crimes and other social problems.This can be achieved by ensuring proper and genuine police reform in the country to overhaul the organization and by bringing to book corrupt officers and men as general and specific deterrence.
Ethnicity, Mobility and Role of Informal Channels: Evidence from Delhi Slums
Authors: Jha Amit Kumar , Singh Nitesh Kumar
Published: September 2015

This study has focused on the well-being of the migrants and explored the role of informal channels among different ethnic groups and its effect on upward mobility. This was made possible by conducting primary surveys in the slums of Delhi. It was found that the extent of upward income movement seems to exceed the downward income movement though the cases of stagnancy and downward occupational mobility aren’t to be ignored.  We concluded that evidences in favour of upward mobility are not overwhelming but it would be equally erroneous to overlook the change that has occurred. With regard to the role of informal channels, we   found that in the initial stages while entering the urban labour market, close relatives (from their regional background) matter a lot but subsequently, it is individual inspiration that keeps him going in the labour market.
De 3 uit 6-voorwaarde voor export van Nederlandse studiefinanciering door niet-actieve EU-burgers
Authors: van Ooik R.H.
Published: September 2015

Het Hof van Justitie had al beslist dat Nederland door een woonplaatsvereiste voor te schrijven, de zogenoemde 3 uit 6-voorwaarde, voor migrerende werknemers en hun gezinsleden om Nederlandse financiering voor buiten Nederland gevolgd hoger onderwijs te kunnen verkrijgen, zijn verplichtingen krachtens artikel 45 VWEU en artikel 7 lid 2 van Verordening (EEG) nr. 1612/68 betreffende het vrije verkeer van werknemers niet was nagekomen. In de hier besproken uitspraak Martens is het de vraag of deze 3 uit 6-voorwaarde ook voor economisch niet-actieve EU-burgers verboden is, vanwege strijd met de bepalingen over het Europees Burgerschap (art. 20 en 21 VWEU).

HvJ 25 februari 2015, zaak C-359/13, B. Martens/Minister van Onderwijs, Cultuur en Wetenschap,
Terra firma-forme dermatosis: A report of ten individuals with Duncan’s dirty dermatosis and literature review
Authors: Greywal Tanya , Cohen Philip R.
Published: September 2015

Background: Terra-firma forme dermatosis, also known as Duncan’s dirty dermatosis, is a benign skin condition that presents as dirt-like plaques in patients of all ages.

Purpose: We describe a series of ten patients that presented with terra-firma forme dermatosis.

Methods and Materials: We reviewed PubMed for the following terms: dermatosis, Duncan’s dirty dermatosis, isopropyl alcohol, terra firma, and terra firma-forme dermatosis. We also reviewed papers containing these terms and their references.

Results: The diagnosis of terra firma-forme dermatosis was confirmed in all patients who had complete resolution of each lesion after the application of 70% isopropyl alcohol.

Conclusions: Terra-firma forme dermatosis is easily diagnosed and treated with 70% isopropyl alcohol. It is important to recognize this benign dermatologic condition since it can be confused with other cutaneous disorders. Therefore, in order to avoid unnecessary referrals, biopsies, blood tests, and medications, we suggest a trial of wiping the skin lesion with 70% isopropyl alcohol pads when the diagnosis of terra-firma forme dermatosis is considered.
Full‐Scale Prechlorine Removal: Impact on Filter Performance and Water Quality
Authors: Stoddart Amina K. , Gagnon Graham A.
Published: September 2015

Conversion from direct filtration to biofiltration in a full‐scale drinking water treatment plant in Halifax, N.S., was assessed in terms of filter performance (e.g., turbidity, head loss) and water quality during a 48‐month project. Conversion was achieved by removing prechlorination, with the overall objective of reducing disinfection by‐product formation. As a result of prechlorine removal, it was hypothesized that the anthracite‐sand filters would provide both particle removal and biological treatment in a single process step. When prechlorine was removed, adenosine triphosphate concentrations on the filter media increased from ∼50 to ∼200–500 ng/cm3. Filter performance analysis revealed that conversion increased the filter effluent turbidity and reduced the filter head loss accumulation rate. Unit filter run volumes and filter run times were maintained. Water quality monitoring indicated that finished water total disinfection by‐products were reduced by ∼10–20 μg/L for trihalomethanes and ∼6–10 μg/L for haloacetic acids.
New Concept for Dual-Layer Hydrophilic/Hydrophobic Composite Membrane for Membrane Distillation
Authors: Bilad Muhammad R. , Al Marzooqi Faisal A. , Arafat Hassan A.
Published: September 2015

This study presents a new concept of a simple method for the synthesis of dual layer hydrophilic/hydrophobic composite membranes for membrane distillation (MD). The membranes were prepared of poly(vinylidenefluoride) (PVDF) by phase inversion. The synthesis was realized by allowing a full or partial penetration of the polymer solution through one or two non-woven support (NWS) layers. This was achieved by proper selection of a thin NWS having high stiffness, high porosity and low surface tension, in combination with a runny polymer solution and sufficient time gap between casting and coagulation. The applied preparation method was effective in yielding dual layer composite membranes. The first layer atop the NWS was a hydrophilic or slightly hydrophobic one (contact angle (CA) of 88-92º), while the bottom layer beneath the NWS was highly hydrophobic (CA=132-140º). The difference in surface energy between the top and bottom layers originated from a difference in morphology. A smooth and dense top layer is formed as a result of an instantaneous demixing, while a porous and multi-scale network with some degrees of spherulitical structure was formed on the bottom by a delayed demixing mechanism. Direct contact MD (DCMD) results showed that the obtained flux was comparable to other composite MD membranes with high salt rejection. Membrane alignment inside the MD module is a critical element in determining the membrane performance and is shown to significantly increase flux when a top facing feed configuration is used.
Composition of late summer diet by semi-domesticated reindeer in different grazing conditions in northernmost Finland
Authors: Bezard Pauline , Brilland Sophie , Kumpula Jouko
Published: September 2015

This study aims to investigate the diet composition of semi-domesticated reindeer (Rangifer tarandus tarandus) in late summer in different kinds of grazing conditions in northernmost Finland. The composition of diet by reindeer was determined on the grounds of microhistological analysis of feces samples collected in early August in different seasonal grazing areas (winter or summer/year-round grazing areas) in three reindeer management districts. Although the proportion of different plant groups varied between the studied districts, the quantified group of ground lichens (which also contained small amounts of mushrooms) was the most abundant, varying from 33.0 to 46.4% in the analyzed samples. In general, there were significant differences in the proportions of lichen between districts, but not between grazing areas. The proportion of lichen in samples increased significantly when the amount of lichen pasture around a sample site increased. The proportion of dwarf shrubs and leaves in samples varied from 24.9 to 37.9% and differed significantly between districts, but not between grazing areas. In the same way, the proportion of graminoids varied between 20.9 and 36.2% and differed significantly between districts and also between grazing areas. Higher amounts of graminoids in feces were observed in summer/year-round grazing areas than in winter grazing areas. Finally, the proportion of bryophytes varied between 2.9 and 6.5% and was significantly different between districts, but not between grazing areas. An increase in old and mature coniferous forest around a sample site significantly increased the amounts of bryophytes in samples. The results indicate that reindeer adapt their summer diet composition according to the availability of food plants. The results also show that when reindeer are allowed to select their summer ranges freely, reindeer tend to use lichen pastures intensively also during summer, which causes a considerable reduction in lichens due to grazing and trampling. Therefore, a proper seasonal pasture rotation system to protect lichen pastures from grazing and trampling, from early spring to late autumn, is an essential part of sustainable pasture use in reindeer herding.
Inferring the seasonal evolution of phytoplankton groups in the Senegalo‐Mauritanian upwelling region from satellite ocean‐color spectral measurements
Authors: Farikou O. , Sawadogo S. , Niang A. , Diouf D. , Brajard J. , Mejia C. , Dandonneau Y. , Gasc G. , Crepon M. , Thiria S.
Published: September 2015

We have investigated the phytoplankton dynamics of the Senegalo‐Mauritanian upwelling region, which is a very productive region, by processing a 13 year set of SeaWiFS satellite ocean‐color measurements using a PHYSAT‐like method. We clustered the spectra of the ocean‐color normalized reflectance (reflectance normalized by a reflectance dependent on chlorophyll‐a concentration only) into 10 significant spectral classes using a Self‐Organized Map (SOM) associated with a hierarchical ascendant classification (HAC). By analyzing a 13 year climatology of these classes, we have been able to outline a coherent scenario describing the Senegalo‐Mauritanian upwelling region in terms of spatiotemporal variability of phytoplankton groups: during the onset of the upwelling (December–February), we mainly observed nanoeukaryote‐type phytoplankton in the coastal area; in April–May, the period corresponding to the maximum chlorophyll‐a concentration, the nanoeukaryote types were replaced by diatom types. This scenario is in agreement with microscope phytoplankton cell observations done during several past cruises.
Gallium: Organometallic Chemistry
Authors: Dagorne Samuel
Published: September 2015

The organometallic chemistry of gallium has attracted significant interest over the past decade. Sterically bulky Ga organometallics with interesting structural/bonding features and the emergence of N‐heterocyclic carbenes for the stabilization of novel structural motifs constitute the most prominent developments. Recent studies on well‐defined Ga(I) organocations and on Ga compounds supported by redox‐active ligands also hold promise for the future of Ga organometallic chemistry.
Lead: Inorganic Chemistry
Authors: Swadźba‐Kwaśny Małgorzata
Published: September 2015

The article covers basic inorganic chemistry of lead. As an introduction, the properties and historical uses of metallic lead are discussed, followed by aspects of lead toxicity, including the toxicity origins and effects of lead poisoning. Properties of lead as a heavy p‐block element are discussed, with emphasis on the modern view of the so‐called “inert pair effect”, including its origin, the influence on stability of lead oxidation states, and on the coordination chemistry of lead(
II
), viz., “sterically active lone pair”. This is followed by an overview of lead inorganic compounds, including halides, pseudohalides, oxides and chalcogenides, hydroxides and their chalcogenide analogs, alkoxides, oxoacids, O‐donors, S‐ and Se‐donors, Group 15 donors, compounds with lead‐transition metal bonds, and finally metallic clusters (Zintl phases). This is by no means a comprehensive review, rather compounds representative for each class were presented. In most sections, structural aspects of each class of compounds are discussed, followed by applications, with the focus on modern uses in material science.
Morphology Controlled Poly(aminophenylboronic acid) Nanostructures as Smart Substrates for Enhanced Capture and Release of Circulating Tumor Cells
Authors: Ouyang Jun , Chen Ming , Bao Wen‐Jing , Zhang Qian‐Wen , Wang Kang , Xia Xing‐Hua
Published: September 2015

A strategy is proposed to achieve an enhanced capture efficiency of and low damage to human leukemic lymphoblasts (CCRF‐CEM) by the synergistic effect of topographical interactions and phenylboronic acid functional groups on nanostructures. To realize this purpose, a simple and template free method to synthesize boronic acid derivative polyaniline bioinspired nanostructures with controlled morphology is established. Different nanostructured morphologies such as nanotexture, nanofibers, nanoparticles, microsphere, and 3D porous network have been prepared by controlling the nucleation and growth rate for polymerization. The phenylboronic acid functional groups on the surface of the nanostructures during poly­merization are used as artificial lectins to reversibly capture and release circulating tumor cells (CTCs) with little damage to the cells. The method presented here is simple, rapid, and highly efficient for CTC capture and release with low cost in materials and instruments.