bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparison of Speech Sound Intervention Delivered by Telepractice and Side-by-Side Service Delivery Models
Authors: Grogan-Johnson Sue , Schmidt Anna Marie , Schenker Jason , Alvares Robin , Rowan Lynne E. , Taylor Jacquelyn
Published: May 2013

Telepractice has the potential to provide greater access to speech-language intervention services for children with communication impairments. Substantiation of this delivery model is necessary for telepractice to become an accepted alternative delivery model. This study investigated the progress made by school-age children with speech sound impairments in side-by-side intervention compared with telepractice intervention. Fourteen children aged 6 through 10 years with identified speech sound disorders were randomly assigned to intervention delivered in a side-by-side or telepractice service delivery model. Intervention was provided twice a week for 30-min individual sessions during a 5-week summer intervention program. Children in both service delivery models made improvement in their speech sound production during the program. There were no significant differences between the two groups on postintervention assessments including standardized assessment and listener judgments of word productions. Measurements of treatment fidelity were also reported. The results of this study support the use of telepractice in the intervention of children’s speech sound disorders.
Disrupting Myths of Poverty in the Face of Resistance
Authors: Pollock Katina , Lopez Ann , Joshee Reva
Published: May 2013

This case disrupts some of the prevalent myths about families from low-income and poor households held by educators. Recognizing the inherent tensions, this case demonstrates the importance of creating equitable and inclusive learning environments. We presented some of the challenges faced by Marcus, a progressive principal, as he attempts to challenge the myths about low-income and poor families held by his teaching staff to create a positive and inclusive learning environment where all students can learn.
Morel_Moreau_Morella: The Metamorphoses of Adolfo Bioy Casares’ Invention in a (Re)Animating Universe
Authors: Lorenzo Hernández María
Published: May 2013

Adolfo Bioy Casares’ short novel The Invention of Morel (La invención de Morel, 2003[1940]) envisioned the wish of human beings to define themselves through technology, indeed to reanimate the human as a technological double in an environment that gradually becomes virtual. This article develops the relationships connecting The Invention of Morel with three animating forms – the phantasmagoria, the automaton, and the machine-environment – to stress the privileged association they make between invention and (re)animation. With this purpose, this article examines key contributions to our understanding of simulation and automata in the field of animation theory, such as Alan Cholodenko’s ‘Speculations on the animation automaton’, but also Joubert-Laurencin’s La lettre volante. Quatre essais sur le cinema d’animation, which directly addresses Bioy Casares’ story as a metaphor of animated cinema. Sigmund Freud’s psychoanalytical approach to the field of aesthetics in ‘The Uncanny’, and subsequent theories like Masahiro Mori’s ‘The Uncanny Valley’, are also taken into consideration.
The Aesthetics of Keyframe Animation: Labor, Early Development, and Peter Foldes
Authors: Tai Peng-yi
Published: May 2013

This article discusses weightless kinetics of computer graphics animation by investigating its core mechanism and aesthetics through the practice of ‘keyframing’, that is, the generation of computer animation by setting ‘keyframes’. The author argues that it is the practice of keyframing that contributes most to the impression of a lack of gravity associated with computer graphics. More importantly, the method of deformation employed in keyframing inadvertently evokes rubber hose animation, the style popular in early animation. Rubbery movement was what struck Eisenstein as ‘plasmatic’ in Disney. Rubber hose animation resurfaced in the pioneering computer animation works by Peter Foldes, who explored free distortion and metamorphosis with the new automated movement. In the end, the technology of keyframe animation may be part of the teleology of labor rationalization, but it has come full circle back to where the animation industry began with rubber hose animation.
Twenty-year route of prevalence of risk factors, treatment patterns, complications, and mortality rate of acute myocardial infarction in Iran
Authors: Ghaffari Samad , Hakim Hadi , Pourafkari Leili , Asl Elnaz Sagheb , Goldust Mohamad
Published: May 2013

Objectives:

Coronary artery diseases are regarded as the main cause of mortality in most countries. The present study aims at evaluating variations and studying its complications in Iranian patients within past 20 years.

Methods:

This cross-sectional analytical–descriptive study retrospectively evaluated the files of 600 patients with acute myocardial infarction during a 20-year period. Basic data and laboratory information, chemotherapies and intervention treatments of patients were registered in special forms and compared regarding the mentioned time intervals.

Results:

There were 440 (73.3%) male and 160 (26.7%) female patients and mean age of the patients was 60.03 ± 11.61 years. Mean duration of hospitalization ( p < 0.001) and prevalence of smoking ( p < 0.001) had significantly decreased in the past two decades. There was no meaningful difference when considering mortality rate ( p = 0.533) and cardiac insufficiency ( p = 0.403).

Conclusion:

The results indicate prominent improvement in the management process of patients suffering from acute myocardial infarction within the past 20 years.
Technique Tip
Authors: Bleazey Scott T. , Brigido Stephen A. , Protzman Nicole M.
Published: May 2013

Open reduction with screw fixation is considered the standard surgical approach for injuries of the Lisfranc complex in athletes. However, multiple incisions are required, which increase the risk for postoperative complications. We present a novel percutaneous reduction and solid screw fixation technique that may be a viable option to address partial incongruous injuries of the Lisfranc complex in athletes. At our institution, no intraoperative or postoperative complications have been encountered. Screw breakage did not occur. Reduction of the second metatarsal was considered anatomic across all patients. All patients have returned to their respective sport without limitation. The percutaneous approach appears to decrease complications while the targeting-reduction guide appears to precisely reduce the injury. Consequently, outcomes have been more consistent and predictable. The authors note that this percutaneous approach is specific to partial incongruous injuries of the Lisfranc complex. When presented with more extensive injuries, the authors advocate an open approach.

Levels of Evidence: Expert Opinion, Level V
Health Literacy Part 1
Authors: Pontius Deborah J.
Published: May 2013

Health literacy promotion techniques are important for the school nurse’s toolkit. Health literacy, an Institute of Medicine objective, is “the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions.” Forty-three percent of the adult population has difficulty understanding basic health information. This article is the first of two articles that will describe techniques for improving verbal (part 1) and written (part 2) health communication.
Application of Platelet-Rich Plasma to Disorders of the Knee Joint
Authors: Metcalf Kathryn B. , Mandelbaum Bert R. , McIlwraith C. Wayne
Published: May 2013

Importance:

The promising therapeutic potential and regenerative properties of platelet-rich plasma (PRP) have rapidly led to its widespread clinical use in musculoskeletal injury and disease. Although the basic scientific rationale surrounding PRP products is compelling, the clinical application has outpaced the research.

Objective:

The purpose of this article is to examine the current concepts around the basic science of PRP application, different preparation systems, and clinical application of PRP in disorders in the knee.

Evidence Acquisition:

A systematic search of PubMed for studies that evaluated the basic science, preparation and clinical application of platelet concentrates was performed. The search used terms, including platelet-rich plasma or PRP preparation, activation, use in the knee, cartilage, ligament, and meniscus. Studies found in the initial search and related studies were reviewed.

Results:

A comprehensive review of the literature supports the potential use of PRP both nonoperatively and intraoperatively, but highlights the absence of large clinical studies and the lack of standardization between method, product, and clinical efficacy. Conclusions and Relevance. In addition to the call for more randomized, controlled clinical studies to assess the clinical effect of PRP, at this point, it is necessary to investigate PRP product composition and eventually have the ability to tailor the therapeutic product for specific indications.
The road to performance ratings is paved with intentions
Authors: Spence Jeffrey R. , Keeping Lisa M.
Published: May 2013

Employee performance appraisals are complex events in organizations. They occur in contextually rich environments and have implications for careers, training opportunities, remuneration, and interpersonal relationships. For years, the study of performance appraisals has mirrored this complexity and has revealed a multitude of variables that can influence the accuracy of performance ratings. Of late, the importance of managers’ intentions as a determinant of performance ratings has gained prominence. What is less understood is where these intentions come from and what determines their relative strength or weakness. In the current paper, we present a model that explains the simultaneous presence and strength of multiple rating intentions that managers can have when rating employee performance.
Acute high-altitude illness: a clinically orientated review
Authors: Smedley Tom , Grocott Michael PW
Published: May 2013

Acute high-altitude illness is an encompassing term for the range of pathology that the unacclimatised individual can develop at increased altitude. This includes acute mountain sickness, high-altitude cerebral oedema and high-altitude pulmonary oedema. These conditions represent an increasing clinical problem as more individuals are exposed to the hypobaric hypoxic environment of high altitude for both work and leisure. In this review of acute high-altitude illness, the epidemiology, risk factors and pathophysiology are explored, before their prevention and treatment are discussed. Appropriate ascent rate remains the most effective acute high-altitude illness prevention, with pharmacological prophylaxis indicated in selected individuals. Descent is the definitive treatment for acute high-altitude illness, with the adjuncts of oxygen and specific drug therapies.
Spiritual Well-Being and Its Relationship to Resilience in Young People
Authors: Smith Lindsay , Webber Ruth , DeFrain John
Published: May 2013

Questions have arisen recently about the role of spiritual well-being in strengthening resilience of youth. To explore this association, this case study focused on the relationships and connectedness of young people who attend one religious organization as a means of enhancing their spiritual well-being. In line with the purposes of an instrumental case study, different sources of data (quantitative and qualitative) were collected on the phenomenon of interest—spiritual well-being. A theoretical purposive sample of 65 people participated in the study. A mixed methods research approach guided this case study, which incorporated both single- and multicase study techniques. Through an abductive analysis process, spiritual well-being and resilience were shown to be interrelated and ecologically bound. This mixed methods case study presents one possible explanation for the often observed yet poorly understood relationship between spiritual well-being and positive youth outcomes, such as resilience.
Grade Retention
Authors: Renaud Gia A.
Published: May 2013

Academic accountability is of great concern, therefore grade retention is being considered for both students with and without disabilities who are not meeting end-of-the-year achievement benchmarks. The purpose of this study was to investigate teacher attitudes toward grade retention and whether practices differ when recommending retention of students with or without disabilities. This mixed-methods study utilized a paper-and-pencil questionnaire using a Likert-type scale, as well as two open-ended questions and a checklist. Teacher interviews were also conducted. The findings of this study indicate that teachers are considering a multitude of factors when considering grade retention for their struggling students. Academic performance was the factor that teachers (77%) indicated the most frequently. Although teachers felt pressure and accountability from high stakes testing, they felt test results should be one of many factors considered in the retention decision.
Physical properties of solution cast poly(styrene–butadiene–styrene)/heteroaromatic poly(azo-thiourea) blends
Authors: Kausar Ayesha , Hussain Syed Tajammul
Published: May 2013

The heteroaromatic azo-polymer poly(azo-thiourea) has been prepared using 4-(4-aminobenzyl)benzenamine and diazonium salt solution of 2,6-diaminopyridine. The polymer was processable using polar organic solvents and had high molar mass of 62 × 103 gmol−1. Various concentrations of azo-filler were blended in solution phase using tetrahydrofuran or dimethylformamide with poly(styrene–butadiene–styrene). Morphology, thermal, and mechanical properties of styrene–butadiene–styrene/poly(azo-thiourea)blends have been studied using field-emission scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, and tensile tests. Field-emission scanning electron microscopy micrographs of styrene–butadiene–styrene/poly(azo-thiourea) blends revealed fine granular filler dispersion in the matrix and development of conducting pathways. Accordingly, filler content from 10 to 60 wt% increased the conductivity from 0.99 × 10−1 to 1.61 S cm−1. A relationship between poly(azo-thiourea) loading and thermal stability of the materials was evident. Temperature for 10 wt% thermogravimetric weight loss increased from 467℃ to 483℃, while glass transition was enhanced from 151℃ to 155℃. Thermal and conductivity properties showed better results relative to pristine elastomer but less significant than the conducting filler used. Tensile properties were also dependent on the solvent used. In the dimethylformamide cast system, elongation at break was 345–387% versus the tetrahydrofuran system at 33–38%. The dimethylformamide cast blends tensile modulus was 599–769 MPa versus 876–1032 MPa for the tetrahydrofuran system. Thermal and conductivity behaviors were the same for both hybrid systems. Stress-induced birefringence in these blends has also been studied to find out the suitability of materials for waveguide applications.
Synthesis and properties of poly(thiourea-azo-naphthyl)/multi-walled carbon nanotube composites
Authors: Kausar Ayesha , Hussain Syed Tajammul
Published: May 2013

An aromatic azo-polymer, poly(thiourea-azo-naphthyl), has been synthesized using 1-(5-thiocarbamoylaminonaphthyl)thiourea and diazonium salt solution of 2,6-diaminopyridine. Poly(thiourea-azo-naphthyl) was easily processable using polar solvents and had high molar mass, 57 × 103 g/mol. Electrically conducting and mechanically and thermally stable polymer/multi-walled carbon nanotube nanocomposites were obtained via melt processing technique. Fine distribution of multi-walled carbon nanotubes in a polymer matrix played an essential role in the preparation of polymer/multi-walled carbon nanotube nanocomposites based on interfacial interaction between multi-walled carbon nanotubes and polymer matrix. Field emission-scanning electron microscopy images revealed good dispersion of filler and adhesion of matrix on the surface of multi-walled carbon nanotubes. Accordingly, increasing the amount of multi-walled carbon nanotubes from 1 to 5 wt% increased the electrical conductivity from 2.42 to 4.11 S cm−1. Percolation behavior of the composite was also studied. Tensile modulus for 1 wt% nanocomposite was 4.2 GPa, which increased up to 6.8 GPa on 5 wt% filler addition. A relationship between nanotube loading and thermal stability of the materials was also observed. Ten percent gravimetric loss increased from 502℃ to 538℃ in the presence of 1 wt% multi-walled carbon nanotube. Similarly, glass transition increased from 227℃ to 245℃ in the presence of 5 wt% multi-walled carbon nanotube. Enhancement of the physical properties of multi-walled carbon nanotube-reinforced polymer nanocomposites was accredited to the non-covalent interactions (π–π interactions and secondary bond forces).
Effect of magnetohydrodynamics on Newtonian calendering
Authors: Siddiqui AM , Zahid M , Rana MA , Haroon T
Published: May 2013

In this paper, an analysis has been presented for the calendering process of incompressible magnetohydrodynamics Newtonian fluid. The lubrication approximation is used to simplify the equations of motion. Exact solutions for velocity profile, pressure gradient, flow rate per unit width, rate of strain, shear stress, maximum shear rate and shear stress at the roll surface are obtained. The value of λ, the distance from the nip to the point where the sheet leaves the rolls, is calculated using Newton–Cotes formula along with the regula-falsi method. Numerical results are presented for pressure distribution, power transmitted to the fluid by both rolls, force separating the two rolls using Newton–Cotes formula with regula-falsi method and Simpson’s rule for different values of magnetic parameter, [Formula: see text]and the corresponding values of λ. Some results are shown graphically. It is found that the magnetic field provides the controlling parameter to increase or decrease power transmission, separation force and distance between attachment and detachment points, which are useful for the calendaring process.
Morphology and crystallographic phase of V–C particles formed in Fe–Cr–Ni–V–C alloys
Authors: Takeda M , Mitome M , Hayakawa H , Nishiuchi S , Tanabe T , Yamamoto S
Published: May 2013

The morphology and crystallographic phase of V–C carbide particles formed in cast Fe–Cr–Ni–V–C alloys were investigated by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy (TEM). The combination of results obtained with these techniques revealed that cuboidal, cruciform and spherical carbide particles were formed, depending on the alloy composition, all having the cubic-VC1−x structure (Fm-3m). Detailed TEM observations suggested that small carbide particles were initially cubic in shape and became spherical with increasing particle size. All cuboidal and spherical carbides were single crystallites with no grain boundary at any particle sizes, even after growing to 6 μm in diameter.
Biomimetic deposition of apatite coatings on biomedical NiTi alloy coated with amorphous titanium oxide by microarc oxidation
Authors: Liu F , Qiu W , Wang H R , Song Y , Wang F P
Published: May 2013

The biomedical NiTi alloy was treated by microarc oxidation (MAO) in H3PO4 electrolyte using DC power supply. The amorphous titanium oxide coating with porous and rough structure was formed on NiTi alloy. The MAO treated NiTi was soaked in a simulated body fluid (1·0SBF) to investigate the biomimetic deposition of apatite on the surface of titanium oxide coated NiTi alloy. It was found that titanium oxide coated NiTi alloy shows an excellent apatite forming ability after soaking in a simulated body fluid (1·0SBF) for 28 days, while no apatite forming ability was observed on bared NiTi alloy, even though soaking time is up to 28 days. The Fourier transformed infrared and X-ray photoelectron spectroscopy results showed that apatite deposited on MAO treated NiTi is a kind of [Formula: see text] incorporated and Ca deficient apatite.
Effect of native oxide film on interaction between stainless steels and liquid Sn
Authors: Zhao Y , Cheng C Q , Cao Z Y , Zhao J
Published: May 2013

The effect of native oxide films on the reaction of liquid Sn with stainless steels has been investigated by analysing the growth of intermetallic layers. The diversity of the oxide layers has been employed by exposure of various stainless steels [martensite stainless steel (MSS), austenite stainless steel (ASS) and duplex stainless steel (DSS)] in air for different times. Liquid tin was prone to metallurgically interact with MSS by formation of interfacial (Fe, Cr)Sn2 intermetallics. The native oxide film on MSS decreased (Fe, Cr)Sn2 layer thickness growth but cannot prevent the intermetallic formation. The reaction of Sn with ASS was hindered by the native oxide layer, and the thickness and coverage ratio of the (Fe, Cr)Sn2 intermetallics decreased with the increasing exposure time in air. The oxide film grown on DSS was stable enough to prevent the formation of (Fe, Cr)Sn2 and changed the tin from metallurgical interaction to physical attachment.
Effect of indium addition on microstructural, mechanical and oxidation properties of suction cast Nb–Si eutectic alloy
Authors: Tiwary C S , Kashyap S , Chattopadhyay K
Published: May 2013

The paper reports effect of small ternary addition of In on the microstructure, mechanical property and oxidation behaviour of a near eutectic suction cast Nb–19·1 at-Si–1·5 at-In alloy. The observed microstructure consists of a combination of two kinds of lamellar structure. They are metal–intermetallic combinations of Nbss– β-Nb5Si3 and Nbss– α-Nb5Si3 respectively having 40–60 nm lamellar spacings. The alloy gives compressive strength of 3 GPa and engineering strain of ∼3 at room temperature. The composite structure also exhibits a large improvement in oxidation resistance at high temperature (1000°C).
Effect of recalescence on microstructure and phase transformation in high carbon steel
Authors: Lenka S , Kundu S , Chandra S , Singh S B
Published: May 2013

This paper deals with the effect of recalescence on the microstructure of high carbon steels. Controlled experiments are conducted with varying cooling rates and different specimen geometries in a thermomechanical simulator to completely or partially suppress the transformation enthalpy. Different amounts of recalescence obtained from various experiments are then correlated with the final microstructures. The results clearly indicate the importance of recalescence and also show the limitations of using thermomechanical simulators in predicting the characteristics of γ→pearlite transformation in high carbon steels. A mathematical model has been developed to predict the phase transformation in high carbon steels under continuous cooling conditions incorporating the influence of recalescence. The newly developed model gives better prediction of microstructure than currently available models in high carbon steels under higher cooling rates.
Life assessment methodologies incoroporating shot peening process effects: Mechanistic consideration of residual stresses and strain hardening Part 1 – effect of shot peening on fatigue resistance
Authors: Soady K A
Published: May 2013

Shot peening is a well known process applied to components in order to improve their fatigue resistance. In recent years, there has been an increasing interest in including the effects of the shot peening process in life assessment models since this would allow a reduction in conservatism compared to those in current application. The present paper seeks to review firstly the effects of the shot peening process (surface roughening, strain hardening and compressive residual stresses) and how the magnitude of these effects can be determined both experimentally and numerically. The reasons for the beneficial effect of shot peening on fatigue resistance are reviewed; this includes consideration of how different operating conditions can affect the magnitude of the benefit. The second part of the review details the life assessment approaches which have been developed to date incorporating these effects and seeks to identify the areas in which further development is still required before the models can be applied in structural integrity assessments.
Microstructure evolution and mechanical properties of high performance Mg–10Gd–2Y–0·5Zn–0·3Zr alloy during heat treatments
Authors: Han X Z , Xu W C , Yuan L , Shan D B
Published: May 2013

The microstructure evolution and mechanical properties of as cast Mg–10Gd–2Y–0·5Zn–0·3Zr during heat treatments were investigated in the present study. The appropriate solution treatment temperature of 530°C for the alloy was identified. The peak tensile yield strength of 202 MPa and elongation of 4·5 are obtained in the alloy aged at 200°C for 80 h. The high strength of the peak aged alloy is mainly ascribed to the dense precipitation of 14H type long period stacking ordered phase and β′ in the matrix during aging process. The different strengthening sources are reasonably evaluated by some conventional strengthening models. In the solution treated alloy, the solid solution strengthening is the main strengthening source to the total tensile yield strength. Nevertheless, the precipitation strengthening is the largest contributor (∼55) to the tensile yield strength of the peak aged alloy also due to the strong strengthening effect of β′ and long period stacking ordered phase. The age hardening response of the cast T6 alloy is compared with that of the forged alloy. Results show that the combined effects of strengthening sources such as microstructure refinement by plastic deformation and precipitation strengthening during aging process are the optimal strengthening method of the present alloy.
First principle study of electronic structure and mechanical properties of Zr doped Al2Cu
Authors: Xu Z. F. , Peng J. Z. , Feng X. Z.
Published: May 2013

First principle calculations are adopted using the pseudopotential plane wave method scheme to investigate the electronic structure and mechanical properties of Zr doped Al–Cu intermetallic compounds Al2Cu. Replacing an Al atom or a Cu atom with a Zr atom, this compound forms the crystal structure of Al15Cu8Zr or Al16Cu7Zr. The results show that the structural stability and alloying ability of doped structures are larger than Al2Cu. Moreover, the structural stability and alloying ability of Al15Cu8Zr are higher than that of Al16Cu7Zr. This indicates that Zr is preferred to replace the position of Al. The mechanical properties of doped structures are increased, such as stiffness and plasticity. However, the ductility decreases, and the corresponding room temperature brittleness becomes larger. Theoretical analysis reveals that these two compounds have strong hybridisation between Al s, p states and Zr d states, which leads to intensify the atomic interaction. Therefore, chemical bonds show a character of covalent bond, and the ductility reduces.
Preparation of Fe2O3/Fe foils by anodic oxidation in saturated NaF solution and calcination
Authors: Su C.-W. , Yang W. , Li J.-M. , Guo J.-M. , Zhang Y.-J.
Published: May 2013

Fe2O3/Fe foils were prepared by anodic oxidation of Fe foils in saturated NaF solution kept at 70°C and subsequent calcination at 400°C. The morphology of anodised Fe foils was affected remarkably by anodic voltage and time. When pulse anodisation was applied, clusters that consisted of nanograins were formed on the Fe foils. The X-ray diffraction and Fourier transform infrared data suggested that the cluster products transformed to Fe2O3 after calcining at 400°C for 2 h. According to thermogravimetry–differential scanning calorimetry data, the transformation began at ∼350°C. The Fe2O3/Fe anodes for Li ion batteries were analysed by means of cyclic voltammograms, electrochemical impedance spectroscopies and discharge/charge curves.
Study of nanostructured Al doped ZnO films
Authors: Rahman A. , Jayaganthan R. , Jain R. K. , Chawla A. K. , Chandra R. , Ambardar R.
Published: May 2013

Electroless Al doped ZnO nanostructured thin films were deposited on soda lime glass in the present work. The wet deposited films were dried in air and subsequently annealed in a muffle furnace in air environment. The film deposited samples were characterised by field emission SEM/energy dispersive spectroscopy, X-ray diffraction and ultraviolet-visible spectrophotometer. Microstructure of the Al doped ZnO film is strongly affected by increasing the deposition time and annealing temperature. Surface and cross-sectional morphology of Al doped ZnO film exhibited the dense microstructure as compared to undoped ZnO films. X-ray analysis shows a (101) preferential growth in all the films. The optical properties of the films were analysed in the spectral range of 300–800 nm. The obtained samples are highly transparent with a visual transmittance of >80% at 450 nm.
Fabrication of ordered ripple patterns on GaAs(100) surface using 60 keV Ar+ beam irradiation
Authors: Kumar T , Kumar M , Verma S , Kanjilal D
Published: May 2013

Ion beam induced ripples have limitations to be used in widespread nanoscale device applications due to the presence of deformity in surface patterns. Defect free ripples can only be produced on binary materials if the ion species, energy and angle of incidence are appropriately chosen. Fabrication of highly ordered defect free ripples is observed on GaAs(100) surfaces after the irradiation of 60 keV Ar+ ion beam for different fluences. Atomic force microscopy study demonstrates that the ordering as well as coarsening of ripples are increased with increase in fluence. X-ray photoelectron spectroscopy was carried out to study the significant role of altered surface composition for the generation of defect free ripples. The evolution of high degrees of order is explained with the help of existing formalisms of coupling between surface topography and preferential sputtering.
Cold spray coating process for corrosion protection: a review
Authors: Bala N. , Singh H. , Karthikeyan J. , Prakash S.
Published: May 2013

Cold spray deposition is an emerging technology that addresses many classic shortcomings of more traditional thermal spray processes. Efforts are under way as of this writing to develop a more comprehensive scientific basis for the cold spray process as well as a wider range of suitable materials and its applications for corrosion protection. This paper presents a tutorial introduction to the cold spray coating process, highlighting the coating formation mechanisms, its characteristics and applications. It includes the comparison of cold spray technique with some popular thermal spray techniques. A thorough survey on the combinations of coatings deposited on diverse substrates with their features has also been detailed with emphasis on its applications for oxidation/corrosion protection.
Defective K-Ras oncoproteins overcome impaired effector activation to initiate leukemia in vivo
Authors: Shieh Angell , Ward Ashley F. , Donlan Kegan L. , Harding-Theobald Emily R. , Xu Jin , Mullighan Charles G. , Zhang Chao , Chen Shann-Ching , Su Xiaoping , Downing James R. , Bollag Gideon E. , Shannon Kevin M.
Published: May 2013

Key Points

Defective Ras oncoproteins initiate T-ALL. Murine T-ALLs lacking PTEN have gene expression profiles similar to human early T-cell precursor ALL and are resistant to MEK inhibition.
Mutations in epigenetic modifiers in the pathogenesis and therapy of acute myeloid leukemia
Authors: Abdel-Wahab Omar , Levine Ross L.
Published: May 2013

Recent studies of the spectrum of somatic genetic alterations in acute myeloid leukemia (AML) have identified frequent somatic mutations in genes that encode proteins important in the epigenetic regulation of gene transcription. This includes proteins involved in the modification of DNA cytosine residues and enzymes which catalyze posttranslational modifications of histones. Here we describe the clinical, biological, and therapeutic relevance of mutations in epigenetic regulators in AML. In particular, we focus on the role of loss-of-function mutations in TET2, gain-of-function mutations in IDH1 and IDH2, and loss-of-function mutations in ASXL1 and mutations of unclear impact in DNMT3A in AML pathogenesis and therapy. Multiple studies have consistently identified that mutations in these genes have prognostic relevance, particularly in intermediate-risk AML patients, arguing for inclusion of mutational testing of these genetic abnormalities in routine clinical practice. Moreover, biochemical, biological, and epigenomic analyses of the effects of these mutations have informed the development of novel therapies which target pathways deregulated by these mutations. Our understanding of the effects of these mutations on hematopoiesis and potential for therapeutic targeting of specific AML subsets is also reviewed here.
The impact of HLA unidirectional mismatches on the outcome of myeloablative hematopoietic stem cell transplantation with unrelated donors
Authors: Hurley Carolyn Katovich , Woolfrey Ann , Wang Tao , Haagenson Michael , Umejiego John , Aljurf Mahmoud , Askar Medhat , Battiwalla Minoo , Dehn Jason , Horan John , Oudshoorn Machteld , Pidala Joseph , Saber Wael , Turner Victoria , Lee Stephanie J. , Spellman Stephen R.
Published: May 2013

Key Points

Unidirectional graft-versus-host vector 7/8 HLA mismatches have the same level of risk as bidirectional 7/8 mismatches. For HLA homozygous recipients, a mismatch at the homozygous locus is preferred over a mismatch at the heterozygous loci.
Implications of DPP4 modification of proteins that regulate stem/progenitor and more mature cell types
Authors: Ou Xuan , O’Leary Heather A. , Broxmeyer Hal E.
Published: May 2013

Dipeptidylpeptidase (DPP) 4 has the potential to truncate proteins with a penultimate alanine, proline, or other selective amino acids at the N-terminus. DPP4 truncation of certain chemokines, colony-stimulating factors, and interleukins have recently been linked to regulation of hematopoietic stem/progenitor cells, more mature blood cells, and other cell types. We believe that the potential role of DPP4 in modification of many regulatory proteins, and their subsequent effects on numerous stem/progenitor and other cell-type functions has not been adequately appreciated. This review addresses the potential implications of the modifying effects of DPP4 on a large number of cytokines and other growth-regulating factors with either proven or putative DPP4 truncation sites on hematopoietic cells, and subsequent effects of DPP4-truncated proteins on multiple aspects of steady-state and stressed hematopoiesis, including stem/progenitor cell, and more mature cell, function.
Role of exhaled nitric oxide as a predictor of atopy
Authors: Romero Karina M , Robinson Colin L , Baumann Lauren M , Gilman Robert H , Hamilton Robert G , Hansel Nadia N , Checkley William ,   PURA Study Investigators
Published: May 2013

Background

The fractional exhaled nitric oxide (FeNO) is a quantitative, noninvasive and safe measure of airways inflammation that may complement the assessment of asthma. Elevations of FeNO have recently been found to correlate with allergic sensitization. Therefore, FeNO may be a useful predictor of atopy in the general population. We sought to determine the diagnostic accuracy of FeNO in predicting atopy in a population-based study.

Methods

We conducted a cross-sectional study in an age- and sex- stratified random sample of 13 to 15 year-olds in two communities in Peru. We asked participants about asthma symptoms, environmental exposures and sociodemographics, and underwent spirometry, assessment of FeNO and an allergy skin test. We used multivariable logistic regression to model the odds of atopy as a function of FeNO, and calculated area-under-the-curves (AUC) to determine the diagnostic accuracy of FeNO as a predictor of atopy.

Results

Of 1441 recruited participants, 1119 (83%) completed all evaluations. Mean FeNO was 17.6 ppb (SD=0.6) in atopics and 11.6 ppb (SD=0.8) in non-atopics (p<0.001). In multivariable analyses, a FeNO>20 ppb was associated with an increase in the odds of atopy in non-asthmatics (OR=5.3, 95% CI 3.3 to 8.5) and asthmatics (OR=16.2, 95% CI 3.4 to 77.5). A FeNO>20 ppb was the best predictor for atopy with an AUC of 68% (95% CI 64% to 69%). Stratified by asthma, the AUC was 65% (95% CI 61% to 69%) in non-asthmatics and 82% (95% CI 71% to 91%) in asthmatics.

Conclusions

FeNO had limited accuracy to identify atopy among the general population; however, it may be a useful indicator of atopic phenotype among asthmatics.
CNV-TV: A robust method to discover copy number variation from short sequencing reads
Authors: Duan Junbo , Zhang Ji-Gang , Deng Hong-Wen , Wang Yu-Ping
Published: May 2013

Background

Copy number variation (CNV) is an important structural variation (SV) in human genome. Various studies have shown that CNVs are associated with complex diseases. Traditional CNV detection methods such as fluorescencein situhybridization (FISH) and array comparative genomic hybridization (aCGH) suffer from low resolution. The next generation sequencing (NGS) technique promises a higher resolution detection of CNVs and several methods were recently proposed for realizing such a promise. However, the performances of these methods are not robust under some conditions,e.g., some of them may fail to detect CNVs of short sizes. There has been a strong demand for reliable detection of CNVs from high resolution NGS data.

Results

A novel and robust method to detect CNV from short sequencing reads is proposed in this study. The detection of CNV is modeled as a change-point detection from the read depth (RD) signal derived from the NGS, which is fitted with a total variation (TV) penalized least squares model. The performance (e.g., sensitivity and specificity) of the proposed approach are evaluated by comparison with several recently published methods on both simulated and real data from the 1000 Genomes Project.

Conclusion

The experimental results showed that both the true positive rate and false positive rate of the proposed detection method do not change significantly for CNVs with different copy numbers and lengthes, when compared with several existing methods. Therefore, our proposed approach results in a more reliable detection of CNVs than the existing methods.
Expression pattern of Protein Kinase C ε during mouse embryogenesis
Authors: Carracedo Sergio , Braun Ursula , Leitges Michael
Published: May 2013

Background

Protein kinase C epsilon (PKCϵ) belongs to the novel PKC subfamily, which consists of diacylglycerol dependent- and calcium independent-PKCs. Previous studies have shown that PKCϵ is important in different contexts, such as wound healing or cancer. In this study, we contribute to expand the knowledge on PKCϵ by reporting its expression pattern during murine midgestation using the LacZ reporter gene and immunostaining procedures.

Results

Sites showing highest PKCϵ expression were heart at ealier stages, and ganglia in older embryos. Other stained domains included somites, bone, stomach, kidney, and blood vessels.

Conclusions

The seemingly strong expression of PKCϵ in heart and ganglia shown in this study suggests a important role of this isoform in the vascular and nervous systems during mouse development. However, functional redundancy with other PKCs during midgestation within these domains and others reported here possibly exists since PKCϵ deficient mice do not display obvious embryonic developmental defects.
Milk yield responses to changes in milking frequency during early lactation are associated with coordinated and persistent changes in mammary gene expression
Authors: Wall Emma H , Bond Jeffrey P , McFadden Thomas B
Published: May 2013

Background

The lactating mammary gland responds to changes in milking frequency by modulating milk production. This response is locally regulated and, in dairy cows, the udder is particularly sensitive during early lactation. Relative to cows milked twice-daily throughout lactation, those milked four-times-daily for just the first 3 weeks of lactation produce more milk throughout that lactation. We hypothesized that the milk yield response would be associated with increased mammary cell turnover and changes in gene expression during frequent milking and persisting thereafter. Cows were assigned to unilateral frequent milking (UFM; left udder halves milked twice-daily; right udder halves milked four-times daily) on days 1 to 21 of lactation, followed by twice-daily milking for the remainder of lactation. Relative to udder halves milked twice-daily, those milked four-times produced more milk during UFM; the difference in milk yield declined acutely upon cessation of UFM after day 21, but remained significantly elevated thereafter. We obtained mammary biopsies from both udder halves on days 21, 23, and 40 of lactation.

Results

Mammary cell proliferation and apoptosis were not affected by milking frequency. We identified 75 genes that were differentially expressed between paired udder halves on day 21 but exhibited a reversal of differential expression on day 23. Among those genes, we identified four clusters characterized by similar temporal patterns of differential expression. Two clusters (11 genes) were positively correlated with changes in milk yield and were differentially expressed on day 21 of lactation only, indicating involvement in the initial milk yield response. Two other clusters (64 genes) were negatively correlated with changes in milk yield. Twenty-nine of the 75 genes were also differentially expressed on day 40 of lactation.

Conclusions

Changes in milking frequency during early lactation did not alter mammary cell population dynamics, but were associated with coordinated changes in mammary expression of at least 75 genes. Twenty-nine of those genes were differentially expressed 19 days after cessation of treatment, implicating them in the persistent milk yield response. We conclude that we have identified a novel transcriptional signature that may mediate the adaptive response to changes in milking frequency.
Genome-wide analysis of the GH3 family in apple (Malus × domestica)
Authors: Yuan Huazhao , Zhao Kai , Lei Hengjiu , Shen Xinjie , Liu Yun , Liao Xiong , Li Tianhong
Published: May 2013

Background

Auxin plays important roles in hormone crosstalk and the plant’s stress response. The auxin-responsive Gretchen Hagen3 (GH3) gene family maintains hormonal homeostasis by conjugating excess indole-3-acetic acid (IAA), salicylic acid (SA), and jasmonic acids (JAs) to amino acids during hormone- and stress-related signaling pathways. With the sequencing of the apple (Malus × domestica) genome completed, it is possible to carry out genomic studies on GH3 genes to indentify candidates with roles in abiotic/biotic stress responses.

Results

Malus sieversii Roem., an apple rootstock with strong drought tolerance and the ancestral species of cultivated apple species, was used as the experimental material. Following genome-wide computational and experimental identification of MdGH3 genes, we showed that MdGH3s were differentially expressed in the leaves and roots of M. sieversii and that some of these genes were significantly induced after various phytohormone and abiotic stress treatments. Given the role of GH3 in the negative feedback regulation of free IAA concentration, we examined whether phytohormones and abiotic stresses could alter the endogenous auxin level. By analyzing the GUS activity of DR5::GUS-transformed Arabidopsis seedlings, we showed that ABA, SA, salt, and cold treatments suppressed the auxin response. These findings suggest that other phytohormones and abiotic stress factors might alter endogenous auxin levels.

Conclusion

Previous studies showed that GH3 genes regulate hormonal homeostasis. Our study indicated that some GH3 genes were significantly induced in M. sieversii after various phytohormone and abiotic stress treatments, and that ABA, SA, salt, and cold treatments reduce the endogenous level of axuin. Taken together, this study provides evidence that GH3 genes play important roles in the crosstalk between auxin, other phytohormones, and the abiotic stress response by maintaining auxin homeostasis.
NaMYC2 transcription factor regulates a subset of plant defense responses in Nicotiana attenuata
Authors: Woldemariam Melkamu G , Dinh Son Truong , Oh Youngjoo , Gaquerel Emmanuel , Baldwin Ian T , Galis Ivan
Published: May 2013

Background

To survive herbivore attack, plants have evolved potent mechanisms of mechanical or chemical defense that are either constitutively present or inducible after herbivore attack. Due to the costs of defense deployment, plants often regulate their biosynthesis using various transcription factors (TFs). MYC2 regulators belong to the bHLH family of transcription factors that are involved in many aspects of plant defense and development. In this study, we identified a novel MYC2 TF from N. attenuata and characterized its regulatory function using a combination of molecular, analytic and ecological methods.

Results

The transcript and targeted metabolite analyses demonstrated that NaMYC2 is mainly involved in the regulation of the biosynthesis of nicotine and phenolamides in N. attenuata. In addition, using broadly-targeted metabolite analysis, we identified a number of other metabolite features that were regulated by NaMYC2, which, after full annotation, are expected to broaden our understanding of plant defense regulation. Unlike previous reports, the biosynthesis of jasmonates and some JA-/NaCOI1-dependent metabolites (e.g. HGL-DTGs) were not strongly regulated by NaMYC2, suggesting the involvement of other independent regulators. No significant differences were observed in the performance of M. sexta on MYC2-silenced plants, consistent with the well-known ability of this specialist insect to tolerate nicotine.

Conclusion

By regulating the biosynthesis of nicotine, NaMYC2 is likely to enhance plant resistance against non-adapted herbivores and contribute to plant fitness; however, multiple JA/NaCOI1-dependent mechanisms (perhaps involving other MYCs) that regulate separate defense responses are likely to exist in N. attenuata. The considerable variation observed amongst different plant families in the responses regulated by jasmonate signaling highlights the sophistication with which plants craft highly specific and fine-tuned responses against the herbivores that attack them.