bluuebunny/crossref_metadata_2025 huggingface dataset:
Bingham plastic fluid flow model in tape casting of ceramics using two doctor blades – analytical approach
Authors: Jabbari M. , Hattel J.
Published: October 2013

One of the most common processes used in manufacturing of multilayer ceramic packages, multilayer capacitors and large scale integration circuits is tape casting. In this process, the wet tape thickness is one of the single most determining parameters affecting the final properties of the product, and it is therefore of great interest to be able to control it. One way to control the tape thickness is to use a two doctor blade configuration in the tape casting machine. In this case, it becomes important to fix the height of the slurry in front of both doctor blades according to the desired tape thickness and casting speed (belt velocity). In the present work, the flow in both doctor blade regions of a slurry is described with a steady state momentum equation in combination with a Bingham plastic constitutive equation, and this is integrated to a closed form analytical solution for both reservoirs based on the desired wet tape thickness and casting speed. The developed model is used to investigate the impact of different material parameters and machine designs on the required slurry height. The solution is compared with experimental findings from the literature, and good agreement is found.
Model for multiple stress affected martensitic transformations, microstructural entropy and consequences on scatter in properties
Authors: Bhadeshia H. K. D. H. , Chintha A. , Kundu S.
Published: October 2013

Building on previous work on stress affected martensitic transformations, a simple theory is presented to enable the calculation of the volume fractions of each martensite variant in an austenite grain, as a function of temperature. Polycrystalline austenite is dealt with by introducing specific textures, so that the orientation of the martensite in any region of the sample is defined. The calculations show that there is strong variant selection even with relatively small applied stresses, and the evolution of overall volume fraction is dominated by the favoured variants. The notion of microstructural entropy, which indicates the level of heterogeneity in the microstructure, is then used to indicate consequences on properties such as the scatter to be expected in toughness. These and further detailed consequences of stress affected transformation are described.
Analysis of damage behaviour based on EBSD method under creep–fatigue conditions for polycrystalline nickel base superalloys
Authors: Kobayashi D. , Miyabe M. , Kagiya Y. , Nagumo Y. , Sugiura R. , Matsuzaki T. , Yokobori A. T.
Published: October 2013

In order to detect creep–fatigue damage before the crack initiation stage, an investigation into damage behaviour based on the electron backscattered diffraction (EBSD) method for a polycrystalline nickel base superalloy has been carried out. The average misorientation within grains increases linearly up to the initiation of cracks with the increase in creep strains. Even if stress distributions exist by stress concentration, assessment in all the damage areas allowed the evaluation of creep damage regardless of geometrical influence. Furthermore, the influence of strain rates, introducing fatigue and testing temperatures are hardly observed in the misorientation analysis. Misorientation almost corresponded to inelastic strain regardless of those influences. Quite a small misorientation caused by fatigue led to an equivalent result between creep conditions and creep–fatigue conditions. It is concluded that the misorientation analysis of damaged materials based on the EBSD method allows the quantitative estimation of creep strain and the assessment of remaining creep fracture life.
Lamellar orientation control of directionally solidified Ti–46Al–0·5W–0·5Si alloy by self-seeding technology
Authors: Fan J. , Guo J. , Long W. , Su Y. , Li X. , Li F. , Fu H.
Published: October 2013

Lamellar structures of Ti–46Al–0·5W–0·5Si (at-) alloy solidifying through the primary α phase were successfully aligned parallel to the growth direction using a self-seeding technology in a Bridgman type directional solidification furnace. At the growth rate of 20 μm s−1 and temperature gradient of 12·1 K mm−1, the α phase grows along the [Formula: see text] direction. Therefore, the parallel lamellar structures, whose lamellar orientation is [Formula: see text] direction, can grow continuously until the end of solidification under these solidification parameters. The original lamellar structures of the unmelted region parallel to the growth direction and suitable solidification parameters are necessary for TiAl alloys solidifying through the primary α phase to control the lamellar orientation. The self-seeding technology gets rid of the cutting and fixing of seeds and simplifies the processing of controlling the lamellar orientation of TiAl alloys. It can promote the engineering applications of the lamellar orientation control of TiAl alloys.
Effect of silicon on recrystallisation of V–Ti microalloyed steel
Authors: Wu D. Y. , Pei J. P. , Gong Y. L. , Fan W. B. , Xiao F. R. , Liao B.
Published: October 2013

The dynamic recrystallisation (DRX) and static recrystallisation (SRX) behaviours of three V–Ti microalloyed steels were studied by the analysis of the true stress–strain curves and the stress relaxation curves under different deformation conditions. The results of DRX showed that deformation activation energy Qdef, peak stress and peak strain increased, as a result of the solute strengthening and dragging effect due to Si. The results of SRX showed that Si increased the SRX activation energy QSRX. The solute retardation parameter for static recrystallisation of Si was calculated. Based on the SRX results, to quantify the drag effect of Si and V, a new model was proposed to describe the time for 50 recrystallisation ( t0·5), which was tested and verified by previously published data on similar steels. Precipitation during recrystallisation could lead to a lower value of the Avrami exponent.
Water modelling of effects of pouring basin and sprue geometry on entrance of air bubbles into mould
Authors: Afsharpour M. , Homayun B. , Boutorabi S. M. A.
Published: October 2013

It has been shown that passing of air through molten metal can have a great contribution to the formation of oxide defects in casting of aluminium alloys. In gravity casting of these alloys, the design of gating system has a considerable effect on the formation of air bubbles and their behaviour afterwards. This paper is aimed to study the effect of pouring basin and sprue design on the quantity of air bubbles entering the mould cavity. In order to do this, water modelling of pouring into several gating systems varying in pouring basin and sprue design was conducted, and quantified results were used to compare the designs in terms of the ability to prevent bubble formation and entrainment. It was concluded that the offset basin with a 1 in. high barrier in bottom is the most efficient design in preventing bubble entrainment.
Constitutive model for AZ31 magnesium alloy based on isothermal compression test
Authors: Luan J. , Sun C. , Li X. , Zhang Q.
Published: October 2013

Isothermal compression tests at temperatures ranging from 523 to 723 K and strain rates from 0·01 to 10 s−1 were performed on AZ31 magnesium alloy to reveal the deformation characteristics. The flow stress–strain curves show that the flow stress reaches a peak value and then decreases to steady values, which characterise a dynamic flow softening. The measured flow stress was modified by friction and temperature correction, which reflect the friction corrected flow stresses are lower than the measured ones and the effect of temperature rise on flow stress is obvious at high strain rate (≥1 s−1). The corrected flow curves were employed to develop the constitutive model. The influence of strain was also incorporated in the constitutive equation by considering the effects of strain on material constants, which were identified using sixth order polynomial. The flow stress predicted by the constitutive model shows good agreement with the corrected stress, which confirmed that the proposed model is effective and accurate for the flow stress of AZ31 magnesium alloy.
Depressing liquid phase separation and macrosegeregation of Fe–Sn immiscible alloys by Cu alloying
Authors: Lu W. Q. , Zhang S. G. , Li J. G.
Published: October 2013

The effect of Cu addition on the liquid phase separation and macrosegregation of Fe0·42Sn0·58 immiscible alloy was investigated based on thermal analysis, microstructural observations, thermodynamic and dynamic calculations. By increasing the Cu content, a structure with drastically diminished or even free of macrosegregation was realised. It revealed that Cu alloying has reduced the Gibbs free energy of mixing and temperature dependent coefficient of interfacial tension of liquids, thus depressing not only the frequency of collision and coagulation of the minor phase globules but also the liquid phase separation. As a viable and convenient means, alloying shows promise in obtaining homogeneous structure of immiscible materials.
Enhancing strength and ductility of AZ31 magnesium alloy sheets by the trapezoid extrusion
Authors: Yang Q. S. , Jiang B. , Zhou G. Y. , He J. J. , Pan F. S.
Published: October 2013

The microstructure evolutions and mechanical properties of AZ31 magnesium alloy sheets processed by the conventional extrusion and the trapezoid extrusion (TE) were investigated. The textural evolutions of TE sheets at near surface are different throughout the sheet thickness direction due to an additional shear deformation. This enforces the basal plane to tilt toward the direction of shear deformation. Moreover, it weakens the basal texture intensity. Trapezoid extrusion process exhibits a considerable grain refinement. Improved strength and ductility of magnesium alloys sheets were achieved by TE approach due to the tilted weak basal texture and the grain refinement.
Effect of high temperature aging on microstructure and mechanical properties of HR3C heat resistant steel
Authors: Bai X. , Pan J. , Chen G. , Liu J. , Wang J. , Zhang T. , Tang W.
Published: October 2013

Microstructure and mechanical properties of the HR3C austenite heat resistant steel were investigated after artificial aging at 650°C for time up to 3000 h. The results show that as the aging time increased, the room temperature tensile and impact fracture mechanisms of the HR3C steel change from trans- to intergranular fracture. M23C6 type carbides and MX type carbonitrides continuously precipitate during aging, leading to the change of the mechanical properties and fracture mode of the steel. Moreover, the dissolution of the coherent twins and the transformation from the incoherent twins to the thermodynamically stable austenite subgrains have great effects on the mechanical properties of the aged steel, too. When increasing the aging time to ≥2000 h, the microstructure and mechanical properties of the steel are nearly constant, indicating a good thermal stability of the HR3C steel at elevated temperature.
Hot ductility of C–Mn and microalloyed steels evaluated for thin slab continuous casting process
Authors: Giri S. K. , Chanda T. , Chatterjee S. , Kumar A.
Published: October 2013

Hot ductility of three grades of C–Mn steel and four grades of microalloyed steel have been evaluated simulating the bending or straightening operation in thin slab continuous casting process. The minimum bending or straightening temperature has been determined from the hot ductility curves generated by plotting per cent reduction in cross-sectional area of specimens against different test temperatures. The results have been discussed by analysing the force elongation curves and the fractographs of all the steels, and possible explanations for the results obtained have been presented. In microalloyed steels containing Nb, multiple troughs are observed in the hot ductility curves instead of single trough observed for remaining steel grades. The ductility is not recovered at 700°C in steels containing Nb, unlike the remaining steel grades. Among the C–Mn steels, steels with higher S content show less ductility. Intergranular fracture is observed in specimens in which ductility obtained is low.
Strain induced martensite formation characteristics of austenite stainless steel during various loading conditions
Authors: Okayasu M. , Fukui H. , Ohfuji H. , Shiraishi T.
Published: October 2013

The strain induced martensitic transformation (SMT) of the austenite stainless steel (SUS 304) under cyclic loading and static loading was investigated directly using electron backscattered diffraction. Two different SMT characteristics are observed, which are attributed to the differences of plastic and twinning deformation. The maximum cyclic stress has a strong influence on the SMT. The total area fraction of the Fe- α′ phase increases significantly when the maximum cyclic load is >80 σUTS. In other words, the SMT is apparently absent when the samples are loaded with less than σmax = 70 σUTS, although such samples are fractured completely. Moreover, there is a clear R ratio effect on the SMT. For example, the loading condition R = −1 gives rise to a strong SMT compared to R = 0·1 due to the more severe strain caused by the compressive stress. In contrast, no clear frequency effect (1 versus 30 Hz) on the SMT is detected, which may be attributed to the same maximum cyclic stress. Like the SMT characteristics under cyclic loading, the proportion of Fe- α′ phase shows no clear increase until the sample is loaded statically to a tensile stress <70 σUTS.
Influence of tungsten on microstructure and wear resistance of iron base hardfacing alloy
Authors: Liu D. S. , Liu R. P. , Wei Y. H.
Published: October 2013

A series of iron based hardfacing alloys with varying tungsten contents were fabricated using slag free self-shielded flux cored wire, and the effects of tungsten addition on microstructure and wear performance were investigated. The experimental results showed that the iron base tungsten free hardfacing alloy has a typical hypereutectic microstructure, which consists of primary hexagonal M7(C, B)3 carbides and eutectic long bar-like M3(C, B) carbides in the austenite and martensite matrix. The addition of tungsten increases the size of primary hexagonal M7(C, B)3 carbides and promotes the formation of martensite, as well as changes the morphology of eutectic carbides. It was found that the eutectic carbides change from the long bar-like shape to the scattered web shape with the increase in tungsten content to 9 wt-, and subsequently change to the plate shape with further increasing the tungsten content to 12 wt-. For the all tungsten containing hardfacing alloys, tungsten exists in both the carbides and matrix uniformly. Results also showed that the wear loss of the sample with 9 wt- tungsten was the smallest among all the samples owing to the higher hardness and reinforced microstructure.
Effect of heat treatment on Al–7Si–0·35Mg–2Cu cast alloys
Authors: Zhang X. H. , Su G. C. , Tang H. Q. , Huang X. Z.
Published: October 2013

The microstructure and mechanical properties of the optimised Al–0·35Mg–7·0Si cast alloys subjected to solid solution treatment followed by aging treatment have been analysed. The results indicate that the overheating treatment temperature of optimised alloy is 508°C. The mechanical properties of alloy with 495°C ×5 h and 500°C ×4 h solid solution treatment are better than that of other experiment conditions. Tensile strength is 239–243 MPa. Hardness is ∼104 HB. Elongation is 4·4–4·8. The main precipitation phases may have Si, Al2Cu, Al6Cu3Ni and AlxCuCe phases whose morphology may be long strip, round, ellipse, flake and block. All specimens were fractured in a mixed mode fracture character consisting of a ductile and brittle manner, and the fractographs are in good agreement with the variations in fracture modes and mechanical properties of different samples.
Study on cracking characteristics on aging of super duplex stainless steel weld metal
Authors: Park H. J. , Lee H. W.
Published: October 2013

In the present study, we carried out a flux cored arc welding using a super duplex stainless steel as a filler metal and analysed the cause of cracking that occurred at the aging treatment for 30 min at 850°C. The stress concentration effect by the notch of the welding bead affected the hot cracking susceptibility, and the impact value of weldment was remarkably decreased due to the precipitation of secondary phases. In addition, the precipitation of σ of the adjacent area to the crack was measured to be higher by ∼12 wt- than the non-adjacent area to the crack. As a result of analysis of fracture plane, it was embrittled by segregation of impurities or inclusions, which acted as a starting point of the crack, and the crack grew according to the widely distributed σ phase.
Toughness anisotropy in X70 and X80 linepipe steels
Authors: Joo M. S. , Suh D.-W. , Bae J.-H. , Bhadeshia H. K. D. H.
Published: October 2013

The anisotropy of mechanical properties in the context of steels used to fabricate large diameter pipes can be detrimental to the design and performance of the pipes. We examine here the anisotropy of strength and toughness, and with the help of detailed characterisation show that there is a complex interaction between the ability of the steel to delaminate on the rolling plane and the crystallographic texture, which promotes brittle fracture on the macroscopic fracture plane of Charpy specimens.
Effect of aging treatment on microstructure and creep behaviour of Sn–Ag and Sn–Ag–Bi solder alloys
Authors: Abd El-Rehim A. F. , Zahran H. Y.
Published: October 2013

The present study was undertaken to investigate the influence of aging temperature on the creep behaviour of Sn–Ag and Sn–Ag–Bi solder alloys at testing temperatures ranging from 333 to 363 K under constant stress of 7·80 MPa. The steady state creep rate was found to increase continuously with increasing aging temperature at all testing temperatures. Results show that addition of Bi to the binary Sn–Ag solder alloy led to a significant increase in the strength and improvement in the creep resistance. The activation energy for the creep process of Sn–Ag and Sn–Ag–Bi solder alloys was found to have an average value of 36 and 45 kJ mol−1 respectively. This might be characterised by diffusion of Ag in Sn. The microstructure of the aged samples for both alloys examined by X-ray diffraction measurements supported the improvement in the creep resistance for Sn–Ag alloy by adding a small trace of Bi.
Evaluation of microstructural evolution of Mg–4Al–xRE in SIMA process based on statistical approach
Authors: Nayyeri M. J. , Haghshenas D. F.
Published: October 2013

Strain induced melt activation (SIMA) for achieving as nearly as possible a spheroidal semisolid structure with minimum entrapped second phase is more practically/economically advantageous compared to other techniques. One prerequisite towards arriving at an effective SIMA process is the use of appropriate methodology for the evaluation/prediction of pertinent factors in such processes. In the present work, the effects of alloying element, induced strain and holding time on three responses, namely, shape factor, particle size diameter and fraction of liquid, were investigated using response surface methodology based on a central composite design. According to statistical analysis and the developed polynomial equation models, it was found that all the first order terms of the independent parameters as well as second order term of alloying element are statistically significant for all the responses. In the case of shape factor, the second order term of time and the interactive term of induced strain and alloying element have statistical significance.
Development of ternary Mg based alloy for soldering of AZ31B magnesium alloy
Authors: Chen Y. , Cong K. , Ma L. , Yao Y. , Liu S. , Long W.
Published: October 2013

Two kinds of ternary Mg based alloys were designed to join the AZ31B magnesium alloy plates by high frequency induction soldering with argon shielding gas. The microstructures and properties of the filler metals and joints were investigated by SEM, X-ray diffraction, differential scanning calorimetry, spreading test and tensile test. The results have shown that the microstructures of Mg–31·5Al–10Sn filler metal mainly consist of Mg17Al12, Mg2Sn and a trace amount of α-Mg phases, while the microstructures of Mg–29·5Zn–1Sn filler metal include α-Mg phase and Mg7Zn3 with a trace of α-Mg and Mg2Sn phases. Both of the filler metals have narrow melting zones; however, the spreading area of the Mg–31·5Al–10Sn filler metal is much larger than that of the Mg–29·5Zn–1Sn filler metal on the AZ31B base metal. The average tensile strength of solder joints with Mg–31·5Al–10Sn filler metal is a little higher than that of the latter solder joints with Mg–29·5Zn–1Sn filler metal.
Influence of addition of carbon nanotubes on structure–properties of Cu–Al–Ni shape memory alloys
Authors: Saud S. N. , Hamzah E. , Abu Bakar T. A. , Abdolahi A.
Published: October 2013

The influence of the addition of 0·2 wt- carbon nanotubes on the microstructure and mechanical properties of Cu based shape memory alloy with a composition of Cu–11·5 wt-Al–4·5 wt-Ni were investigated using optical microscopy, X-ray diffraction, scanning electron microscopy and a universal testing machine. The experimental results show that the carbon nanotubes’ (CNTs’) addition has an effective influence on the martensite–austenite transformation temperatures, type, behaviour and morphology. Furthermore, the addition of CNTs can control the grain size and thus the tensile strength, elongation, fracture stress–strain, yield strength and shape memory effect can be enhanced. Remarkably, the shape recovery ratio reached ∼68 of the original shape; this can be attributed to the precipitation and formation of the CNTs into the microstructure, effectively on the grain boundaries, which can help to reduce/relief the concentration of internal stress.
Effect of H3PO4 anodising variations on Al–epoxy adhesion strength
Authors: Mohagheghi S. , Hatefi A. , Kianvash A.
Published: October 2013

High adhesion strength of polymeric coatings on Al alloys requires special Al surface pretreatment. The formation of a thin layer of anodic Al oxide (AAO) leads to a strong polymer/Al bond. In this work, a thermosetting epoxy coating was applied on anodised Al surfaces. The effects of the electrolyte temperature, anodising voltage and time on the adhesion strength of coated samples were examined using a pull-off method. Surface morphology and topography of AAO layer were studied using field emission scanning electron microscopy and atomic force microscopy, respectively. Hydrophilic behaviour of the nanostructure anodised layer was investigated by a contact angle test. The results showed that the morphology of AAO layer has a remarkable impact on the adhesion strength. Morphological changes in the AAO layer from customary pore- to whisker-like structure led to a noticeable improvement in the strength of epoxy coatings; the latter structure was highly hydrophilic.
Prospective cohort study comparing intravenous busulfan to total body irradiation in hematopoietic cell transplantation
Authors: Bredeson Christopher , LeRademacher Jennifer , Kato Kazunobu , DiPersio John F. , Agura Edward , Devine Steven M. , Appelbaum Frederick R. , Tomblyn Marcie R. , Laport Ginna G. , Zhu Xiaochun , McCarthy Philip L. , Ho Vincent T. , Cooke Kenneth R. , Armstrong Elizabeth , Smith Angela , Rizzo J. Douglas , Burkart Jeanne M. , Pasquini Marcelo C.
Published: October 2013

Key Points

Compared with TBI, IV-BU resulted in superior survival with no increased risk for relapse or TRM. The results support the use of myeloablative IV-BU vs TBI-based conditioning regimens for treatment of myeloid malignancies.
The scoring of poses in protein-protein docking: current capabilities and future directions
Authors: Moal Iain H , Torchala Mieczyslaw , Bates Paul A , Fernández-Recio Juan
Published: October 2013

Background

Protein-protein docking, which aims to predict the structure of a protein-protein complex from its unbound components, remains an unresolved challenge in structural bioinformatics. An important step is the ranking of docked poses using a scoring function, for which many methods have been developed. There is a need to explore the differences and commonalities of these methods with each other, as well as with functions developed in the fields of molecular dynamics and homology modelling.

Results

We present an evaluation of 115 scoring functions on an unbound docking decoy benchmark covering 118 complexes for which a near-native solution can be found, yielding top 10 success rates of up to 58%. Hierarchical clustering is performed, so as to group together functions which identify near-natives in similar subsets of complexes. Three set theoretic approaches are used to identify pairs of scoring functions capable of correctly scoring different complexes. This shows that functions in different clusters capture different aspects of binding and are likely to work together synergistically.

Conclusions

All functions designed specifically for docking perform well, indicating that functions are transferable between sampling methods. We also identify promising methods from the field of homology modelling. Further, differential success rates by docking difficulty and solution quality suggest a need for flexibility-dependent scoring. Investigating pairs of scoring functions, the set theoretic measures identify known scoring strategies as well as a number of novel approaches, indicating promising augmentations of traditional scoring methods. Such augmentation and parameter combination strategies are discussed in the context of the learning-to-rank paradigm.
The expression of diacylglycerol kinase theta during the organogenesis of mouse embryos
Authors: Ueda Shuji , Tu-Sekine Becky , Yamanoue Minoru , Raben Daniel M , Shirai Yasuhito
Published: October 2013

Background

Diacylglycerol kinase (DGK) is a key enzyme that regulates diacylglycerol (DG) turnover and is involved in a variety of physiological functions. The isoform DGKθ has a unique domain structure and is the sole member of type V DGK. To reveal the spatial and temporal expression of DGKθ we performed immunohistochemical staining on paraffin sections of mouse embryos.

Results

At an early stage of development (E10.5 and 11.5), the expression of DGKθ was prominently detected in the brain, spinal cord, dorsal root ganglion, and limb bud, and was also moderately detected in the bulbus cordis and the primordium of the liver and gut. At later stages (E12.5 and 14.5), DGKθ expression persisted or increased in the neocortex, epithalamus, hypothalamus, medulla oblongata, and pons. DGKθ was also evident in the epidermis, and nearly all epithelia of the oropharyngeal membrane, digestive tract, and bronchea. At prenatal developmental stages (E16.5 and E18.5), the expression pattern of DGKθ was maintained in the central nervous system, intestine, and kidney, but was attenuated in the differentiated epidermis.

Conclusion

These results suggest that DGKθ may play important physiological roles not only in the brain, but also in diverse organs and tissues during the embryonic stages.
Stacking resistance to crown gall and nematodes in walnut rootstocks
Authors: Walawage Sriema L , Britton Monica T , Leslie Charles A , Uratsu Sandra L , Li YingYue , Dandekar Abhaya M
Published: October 2013

Background

Crown gall (CG) (Agrobacterium tumefaciens) and the root lesion nematodes (RLNs) (Pratylenchus vulnus) are major challenges faced by the California walnut industry, reducing productivity and increasing the cost of establishing and maintaining orchards. Current nematode control strategies include nematicides, crop rotation, and tolerant cultivars, but these methods have limits. Developing genetic resistance through novel approaches like RNA interference (RNAi) can address these problems. RNAi-mediated silencing of CG disease in walnut (Juglans regiaL.) has been achieved previously. We sought to place both CG and nematode resistance into a single walnut rootstock genotype using co-transformation to stack the resistance genes.A.tumefaciens, carrying self-complimentary iaaM and ipt transgenes, andAgrobacterium rhizogenes, carrying a self-complimentary Pv010 gene fromP.vulnus, were used as co-transformation vectors. RolABC genes were introduced by the resident T-DNA in theA.rhizogenesRi-plasmid used as a vector for plant transformation. Pv010 and Pv194 (transgenic control) genes were also transferred separately usingA.tumefaciens. To test for resistance, transformed walnut roots were challenged withP.vulnusand microshoots were challenged with a virulent strain ofA.tumefaciens.

Results

Combining the two bacterial strains at a 1:1 rather than 1:3 ratio increased the co-transformation efficiency. Although complete immunity to nematode infection was not observed, transgenic lines yielded up to 79% fewer nematodes per root followingin vitroco-culture than untransformed controls. Transgenic line 33-3-1 exhibited complete crown gall control and 32% fewer nematodes. The transgenic plants had thicker, longer roots than untransformed controls possibly due to insertion of rolABC genes. When the Pv010 gene was present in roots with or without rolABC genes there was partial or complete control of RLNs. Transformation using only one vector showed 100% control in some lines.

Conclusions

CG and nematode resistance gene stacking controlled CG and RLNs simultaneously in walnuts. Silencing genes encoding iaaM, ipt, and Pv010 decrease CG formation and RLNs populations in walnut. Beneficial plant genotype and phenotype changes are caused by co-transformation usingA.tumefaciensandA.rhizogenesstrains. Viable resistance against root lesion nematodes in walnut plants may be accomplished in the future using this gene stacking technology.
Impacts of clinicopathologic and operative factors on short-term and long-term survival in renal cell carcinoma with venous tumor thrombus extension: a multi-institutional retrospective study in Japan
Authors: Hirono Masanori , Kobayashi Mikio , Tsushima Tomoyasu , Obara Wataru , Shinohara Nobuo , Ito Keiichi , Eto Masatoshi , Takayama Tatsuya , Fujii Yasuhisa , Nishikido Masaharu , Kimura Go , Kishida Takeshi , Takahashi Masayuki , Miyao Noriomi , Naya Yukio , Abe Takashige , Fujioka Tomoaki , Ito Kazuto , Naito Seiji ,   Members of the Japanese Society of Renal Cancer
Published: October 2013

Background

Although the percentage of patients with renal cell carcinoma (RCC) extending into venous systems is unexpectedly high, the prognostic impact and independency of venous tumor thrombus-related factors on overall survival (OS) remain controversial. Furthermore, the prognostic impact of various clinicopathologic factors including tumor thrombus-related factors on OS may change with elapsed years after the intervention and also with follow-up duration of participants. The aim of the study is to explore independent and universal predictive preoperative and intraoperative clinicopathologic factors on OS in patients with RCC extending into venous systems using subgroup analysis in terms of restricted follow-up duration and yearly-based survivors.

Methods

Between 1980 and 2009, 292 patients diagnosed with RCC with venous tumor thrombus were retrospectively registered for this study. The prognostic impacts of various clinicopathologic and surgical treatment factors including levels of venous thrombus, venous wall invasion status and likelihood of aggressive cytoreductive operation, were investigated using Kaplan-Meier method and following multivariate Cox proportional hazards model for all patients and those still alive at 1, 2, and 3 years of follow-up. To investigate the impact of follow-up duration on the statistical analyses, multivariate logistic regression analyses were used to explore prognostic factors using restricted data until 1, 2, and 3 years of follow-up.

Results

The median follow-up duration was 40.4 months. The 5-year OS was 47.6%. Several independent predictive factors were identified in each subgroup analysis in terms of yearly-based survival and restricted follow-up duration. The presence of tumor thrombus invading to venous wall was independently related to OS in the full-range follow-up data and in survivors at 2 and 3 years of follow-up. Using restricted follow-up data until 1, 2, and 3 years of follow-up, many independent predictive factors changed with follow-up duration, but surgical category could be universal and independent predictive factors.

Conclusion

The most universal factors affecting improvement both in short-term and long-term survivals could be cytoreductive surgery and absence of venous wall invasion. It may mean that feasible aggressive cytoreductive operation following more reliable preoperative imaging for predicting venous wall invasion status would improve OS for patients with RCC extending into venous systems.
Application of proteomics to identify the target molecules involved in Lonicera japonica-induced photokilling in human lung cancer CH27 cells
Authors: Liao Jung C , Chang Wen T , Lan Yu H , Hour Mann J , Lee Hong Z
Published: October 2013

Background

The Lonicera japonica has been used as natural and healthy drink for its anti-inflammatory effect and pleasant odor in China and Taiwan.

Methods

2D electrophoresis was used to analyze the proteins involved in photoactivated Lonicera japonica-induced CH27 cell apoptosis. The fluorescent dyes MitoTracker Red CMXRos, calcein AM and JC-1 were used to elucidate mitochondrial function. The protein expression was performed by Western blotting. Fluorescent image of endoplasmic reticulum was accomplished by using ER-Tracker Green. This study used fluorescent dye CM-H2DCFDA to detect intracellular generation of reactive oxygen species.

Results

The identified proteins can be classified into three major groups, which include proteins involved in mitochondrial function, cytoskeleton-related proteins and proteins associated with endoplasmic reticulum (ER) stress. Photoactivated Lonicera japonica caused a significant effect on the mitochondrial function and ER stress in CH27 cells. The reactive oxygen species producing was found to be involved in photoactivated Lonicera japonica-induced CH27 cell apoptosis.

Conclusion

Mitochondria and endoplasmic reticulum are the integral targets in photoactivated Lonicera japonica-induced CH27 cell apoptosis. We also demonstrated that ethyl acetate fraction of Lonicera japonica extracts caused photocytotoxicity in a dose-dependent manner in CH27 cells. This could explain the fact that the ethyl acetate fraction of Lonicera japonica extracts may contain compounds which exhibit the photosensitizing activity in CH27 cells.
Hyper secretion of Thermobifida fusca β-glucosidase via a Tat-dependent signal peptide using Streptomyces lividans
Authors: Miyazaki Takaya , Noda Shuhei , Tanaka Tsutomu , Kondo Akihiko
Published: October 2013

Background

Protein production as secretory-form is a powerful tool in industrial enzyme production due to the simple purification procedure. Streptomyces lividans is a versatile host for secretory production of useful proteins. In order to expand the amount of secreted protein, signal peptide sequences, which encourage protein secretion from inside cell to extracellular environment, are one of the most significant factors. In this study, we focused on Streptomyces lividans as a host strain to secrete useful proteins, and screened for signal peptides from the biomass-degradation enzymes derived from Thermobifida fusca YX and S. lividans.

Results

Three candidate signal peptides were isolated and evaluated for their protein secretion ability using β-glucosidase derived from T. fusca YX, which is a non-secreted protein, as a model protein. Using S. lividans xylanase C signal peptide, the amount of produced the β-glucosidase reached 10 times as much as that when using Streptomyces cinnamoneus phospholipase D signal peptide, which was identified as a versatile signal peptide in our previous report. In addition, the introduction of the β-glucosidase fused to xylanase C signal peptide using two kinds of plasmid, pUC702 and pTYM18, led to further protein secretion, and the maximal level of produced the β-glucosidase increased up to 17 times (1.1 g/l) compared to using only pUC702 carrying the β-glucosidase fused to S. cinnamoneus phospholipase D signal peptide.

Conclusion

In the present study, we focused on signal peptide sequences derived from biomass degradation enzymes, which are usually secreted into the culture supernatant, and screened for signal peptides leading to effective protein secretion. Using the signal peptides, the hyper-protein secretion system was successfully demonstrated for the cytoplasmic β-glucosidase.
Adherence to human lung microvascular endothelial cells (HMVEC-L) of Plasmodium vivax isolates from Colombia
Authors: De las salas Briegel , Segura Cesar , Pabón Adriana , Lopes Stefanie CP , Costa Fabio TM , Blair Silvia
Published: October 2013

Background

For years Plasmodium vivax has been considered the cause of benign malaria. Nevertheless, it has been observed that this parasite can produce a severe disease comparable to Plasmodium falciparum. It has been suggested that some physiopathogenic processes might be shared by these two species, such as cytoadherence. Recently, it has been demonstrated that P. vivax-infected erythrocytes (Pv-iEs) have the capacity to adhere to endothelial cells, in which intercellular adhesion molecule-1 (ICAM-1) seems to be involved in this process.

Methods

Adherence capacity of 21 Colombian isolates, from patients with P. vivax mono-infection to a microvascular line of human lung endothelium (HMVEC-L) was assessed in static conditions and binding was evaluated at basal levels or in tumor necrosis factor (TNF) stimulated cells. The adherence specificity for the ICAM-1 receptor was determined through inhibition with an anti-CD54 monoclonal antibody.

Results

The majority of P. vivax isolates, 13 out of 21 (61.9%), adhered to the HMVEC-L cells, but P. vivax adherence was at least seven times lower when compared to the four P. falciparum isolates. Moreover, HMVEC-L stimulation with TNF led to an increase of 1.6-fold in P. vivax cytoadhesion, similar to P. falciparum isolates (1.8-fold) at comparable conditions. Also, blockage of ICAM-1 receptor with specific antibodies showed a significant 50% adherence reduction.

Conclusions

Plasmodium vivax isolates found in Colombia are also capable of adhering specifically in vitro to lung endothelial cells, via ICAM-1 cell receptor, both at basal state and after cell stimulation with TNF. Collectively, these findings reinforce the concept of cytoadherence for P. vivax, but here, to a different endothelial cell line and using geographical distinct isolates, thus contributing to understanding P. vivax biology.
An efficient framework for estimation of muscle fiber orientation using ultrasonography
Authors: Ling Shan , Chen Bin , Zhou Yongjin , Yang Wan-Zhang , Zhao Yu-Qian , Wang Lei , Zheng Yong-Ping
Published: October 2013

Background

Muscle fiber orientation (MFO) is an important parameter related to musculoskeletal functions. The traditional manual method for MFO estimation in sonograms was labor-intensive. The automatic methods proposed in recent years also involved voting procedures which were computationally expensive.

Methods

In this paper, we proposed a new framework to efficiently estimate MFO in sonograms. We firstly employed Multi-scale Vessel Enhancement Filtering (MVEF) to enhance fascicles in the sonograms and then the enhanced images were binarized. Finally, line-shaped patterns in the binary map were detected one by one, according to their shape properties. Specifically speaking, for the long-and-thinner regions, the orientation of the targeted muscle fibre was directly computed, without voting procedures, as the orientation of the ellipse that had the same normalized second central moments as the region. For other cases, the Hough voting procedure might be employed for orientation estimation. The performance of the algorithm was evaluated using four various group of sonograms, which are a dataset used in previous reports, 33 sonograms of gastrocnemius from 11 young healthy subjects, one sonogram sequence including 200 frames from a subject and 256 frames from an aged subject with cerebral infarction respectively.

Results

It was demonstrated in the experiments that measurements of the proposed method agreed well with those of the manual method and achieved much more efficiency than the previous Re-voting Hough Transform (RVHT) algorithm.

Conclusions

Results of the experiments suggested that, without compromising the accuracy, in the proposed framework the previous orientation estimation algorithm was accelerated by reduction of its dependence on voting procedures.
Magnetic resonance of the NiFe2O4 nanoparticles in the gigahertz range
Authors: Shi Zhenhua , Zhang Jing , Gao Daqiang , Zhu Zhonghua , Yang Zhaolong , Zhang Zhipeng , Xue Desheng
Published: October 2013

We report an adjustable magnetic resonance frequency from 1.45 to 2.54 GHz for NiFe2O4 nanoparticles which were prepared by a sol–gel process. X-ray diffraction and scanning electron microscopy results indicate that the samples are polycrystalline nanoparticles, and the size of the particles increases obviously with the thermal treatment temperature. The consequence of the surface composition suggests that the oxygen defects are present in the nanoparticle surface, and this surface magnetic state can show a strong surface anisotropy. With decreasing size of the particle, the surface magnetic effect is predominant, resulting in an increase of resonance frequency for NiFe2O4 nanoparticles. This finding provides a new route for NiFe2O4 materials that can be used in the gigahertz range.
Ability of HIV-1 Nef to downregulate CD4 and HLA class I differs among viral subtypes
Authors: Mann Jaclyn K , Byakwaga Helen , Kuang Xiaomei T , Le Anh Q , Brumme Chanson J , Mwimanzi Philip , Omarjee Saleha , Martin Eric , Lee Guinevere Q , Baraki Bemuluyigza , Danroth Ryan , McCloskey Rosemary , Muzoora Conrad , Bangsberg David R , Hunt Peter W , Goulder Philip JR , Walker Bruce D , Harrigan P Richard , Martin Jeff N , Ndung’u Thumbi , Brockman Mark A , Brumme Zabrina L
Published: October 2013

Background

The highly genetically diverse HIV-1 group M subtypes may differ in their biological properties. Nef is an important mediator of viral pathogenicity; however, to date, a comprehensive inter-subtype comparison of Nef in vitro function has not been undertaken. Here, we investigate two of Nef’s most well-characterized activities, CD4 and HLA class I downregulation, for clones obtained from 360 chronic patients infected with HIV-1 subtypes A, B, C or D.

Results

Single HIV-1 plasma RNA Nef clones were obtained from N=360 antiretroviral-naïve, chronically infected patients from Africa and North America: 96 (subtype A), 93 (B), 85 (C), and 86 (D). Nef clones were expressed by transfection in an immortalized CD4+ T-cell line. CD4 and HLA class I surface levels were assessed by flow cytometry. Nef expression was verified by Western blot. Subset analyses and multivariable linear regression were used to adjust for differences in age, sex and clinical parameters between cohorts. Consensus HIV-1 subtype B and C Nef sequences were synthesized and functionally assessed. Exploratory sequence analyses were performed to identify potential genotypic correlates of Nef function. Subtype B Nef clones displayed marginally greater CD4 downregulation activity (p = 0.03) and markedly greater HLA class I downregulation activity (p < 0.0001) than clones from other subtypes. Subtype C Nefs displayed the lowest in vitro functionality. Inter-subtype differences in HLA class I downregulation remained statistically significant after controlling for differences in age, sex, and clinical parameters (p < 0.0001). The synthesized consensus subtype B Nef showed higher activities compared to consensus C Nef, which was most pronounced in cells expressing lower protein levels. Nef clones exhibited substantial inter-subtype diversity: cohort consensus residues differed at 25% of codons, while a similar proportion of codons exhibited substantial inter-subtype differences in major variant frequency. These amino acids, along with others identified in intra-subtype analyses, represent candidates for mediating inter-subtype differences in Nef function.

Conclusions

Results support a functional hierarchy of subtype B > A/D > C for Nef-mediated CD4 and HLA class I downregulation. The mechanisms underlying these differences and their relevance to HIV-1 pathogenicity merit further investigation.
Deficiency for the ER-stress transducer OASIS causes severe recessive osteogenesis imperfecta in humans
Authors: Symoens Sofie , Malfait Fransiska , D’hondt Sanne , Callewaert Bert , Dheedene Annelies , Steyaert Wouter , Bächinger Hans Peter , De Paepe Anne , Kayserili Hulya , Coucke Paul J
Published: October 2013

Osteogenesis imperfecta (OI) is a clinically and genetically heterogeneous brittle bone disorder. Whereas dominant OI is mostly due to heterozygous mutations in either COL1A1 or COL1A2, encoding type I procollagen, recessive OI is caused by biallelic mutations in genes encoding proteins involved in type I procollagen processing or chaperoning. Hitherto, some OI cases remain molecularly unexplained. We detected a homozygous genomic deletion of CREB3L1 in a family with severe OI. CREB3L1 encodes OASIS, an endoplasmic reticulum-stress transducer that regulates type I procollagen expression during murine bone formation. This is the first report linking CREB3L1 to human recessive OI, thereby expanding the OI gene spectrum.
TEACCH-based group social skills training for children with high-functioning autism: a pilot randomized controlled trial
Authors: Ichikawa Kayoko , Takahashi Yoshimitsu , Ando Masahiko , Anme Tokie , Ishizaki Tatsuro , Yamaguchi Hinako , Nakayama Takeo
Published: October 2013

Background

Although social skills training programs for people with high-functioning autism (HFA) are widely practiced, the standardization of curricula, the examination of clinical effectiveness, and the evaluation of the feasibility of future trials have yet to be done in Asian countries. To compensate for this problem, a Japanese pilot randomized controlled trial (RCT) of the Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH)-based group social skills training for children with HFA and their mothers was conducted.

Methods

Eleven children with HFA, aged 5–6 years, and their mothers were randomly assigned to the TEACCH program (n=5) or a waiting-list control group (n=6). The program involved comprehensive group intervention and featured weekly 2-hour sessions, totaling 20 sessions over six months. The adaptive behaviors and social reciprocity of the children, parenting stress, and parent–child interactions were assessed using the Strengths and Difficulties Questionnaire (SDQ), Parenting Stress Index (PSI), Beck depression inventory-II (BDI-II), and Interaction Rating Scale (IRS).

Results

Through this pilot trial, the intervention and evaluation of the program has been shaped. There were no dropouts from the program and the mothers’ satisfaction was high. The outcome measurements improved more in the program group than in the control group, with moderate effect sizes (SDQ, 0.71; PSI, 0.58; BDI-II, 0.40; and IRS, 0.69). This pilot trial also implied that this program is more beneficial for high IQ children and mothers with low stress than for those who are not.

Conclusion

We have standardized the TEACCH program, confirmed the feasibility of a future trial, and successfully estimated the positive effect size. These findings will contribute to a larger trial in the future and to forthcoming systematic reviews with meta-analyses.

Trial registration

UMIN000004560