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Thermomechanical processing of metallic glasses can, remarkably, induce significant changes in structure and properties, even when the imposed macroscopic strains are well within the elastic regime. The changes can take the glasses to higher-energy "rejuvenated" or lower-energy "aged" states, with rejuvenation being of particular interest as it improves their mechanical properties. It has generally been assumed that the induced property changes would evolve monotonically with the extent of processing. We show that with sufficiently intense ultrasonic elastic processing, the intrinsic structural competition between damage and repair facilitated by increased atomic mobility can lead to oscillatory energy storage. The uncovering of this behavior forces reconsideration about the range of energy states attainable in metallic glasses by elastic deformation and may provide opportunities. [ABSTRACT FROM AUTHOR]

Abstract Integral-algebraic equations (IAEs) are coupled systems of Volterra integral equations of the first and second kind which naturally arise in many applications in mathematical physics. In this paper, we solve the IAEs of index-1 by Sinc-collocation discretization and prove that the discrete solutions converge to the true solutions of the IAEs exponentially. The discrete solutions are determined by linear systems which can be effectively solved by suitable iteration methods. Numerical examples are given to illustrate the effective performance of our method. [ABSTRACT FROM AUTHOR]

In this work, we present an efficient spectral-collocation method for numerical solution of a class of nonlinear weakly singular Volterra integral equations. This type of equations typically has a singular behavior at the left endpoint of the interval of integration. For overcoming this non-smooth behavior, we apply the Jacobi-collocation method. The convergence analysis of the proposed method is investigated in the L ∞ and the weighted L 2 norms and the results of several numerical experiments are presented which support the theoretical results. The computed results are compared wherever possible with those already available in the literature. [ABSTRACT FROM AUTHOR]

Cucumis melo L. subsp . agrestis var. agrestis (Naudin) Pangalo (wild melon) is an invasive plant in many parts of Asia and North America. The reproduction of this species is by seeds, thus laboratory experiments were conducted in order to determine the cardinal temperatures and the effects of fluctuating temperature, heat, flooding stress, pH, seed longevity, and depth of burial on wild melon seed germination and seedling emergence. Of the three models tested, the intersected lines model best estimated the cardinal temperatures. The base, optimum, and maximum temperatures for wild melon seed germination were estimated as 20, 35, and 45 °C, respectively. The highest germination rates of wild melon were obtained at 30/20 °C and 35/25 °C (day/night). Only long exposure periods (up to 10 days) at 90 °C or greater than 5 min at 120 °C were efficient at reducing the germination of wild melon seeds. Flooding had limited impact on reducing wild melon seed germination until the third month after the treatment. The seeds of this weed germinated across a wide range of pH values, but germination rates were higher under acidic (pH 5) rather than basic (pH 8 and 9) conditions. Seed germination of wild melon, declined to 50% by the 23rd month after burial in the soil at 15 cm depth. Emergence of wild melon seedlings was higher at shallower burial depths than at deeper ones. These results suggest that the successful invasion of wild melon in an area can be explained, in part, by its tolerance to a wide range of environmental conditions. The combination of seed longevity, lack of seed dormancy and rapid seed germination under favourable climatic conditions may explain its rapid establishment as a weed in summer crops. Among the management strategies that can be used to limit the infestation of wild melon in the fields, burying seed deeply during soil preparation seems to be the most promising. [ABSTRACT FROM AUTHOR]

The kinetics of glass transition and the fragility of Zr 55 Cu 30 Al 10 Ni 5 and (Zr 55 Cu 30 Al 10 Ni 5) 98 Nb 2 metallic glasses were investigated by the calorimetric measurements. The Nb minor addition narrows the width of glass transition, accelerates the relaxation process during glass transition, and decreases the energy barrier of glass transition. In addition, the fragility was evaluated in terms of the kinetic fragility index. While both alloys can be classified as intermediate glass formers, the Nb minor addition remarkably decreases the fragility and a stronger glass is achieved by the microalloying process. The lower fragility in the Nb-containing alloy is accompanied by higher degree of short-range ordering inferred from structural characterizations, formation of nanoscale chemical heterogeneities evidenced from the energy-dispersive X-ray spectroscopy (EDS) results, and deteriorated plasticity evaluated from the bending experiments. Our results highlight positive correlations between the fragility and the plasticity of the studied glasses. [Display omitted] • Glass transition kinetics and fragility of Zr 55 Cu 30 Al 10 Ni 5 and (Zr 55 Cu 30 Al 10 Ni 5) 98 Nb 2 metallic glasses were studied. • The activation energy of glass transition as well as the width of glass transition decrease by Nb addition. • Nb-containing alloy is a stronger glass former and has considerably smaller values of the kinetic fragility index. • Nb minor addition introduces nanoscale chemical heterogeneities. • Correlations between fragility and plasticity were observed. [ABSTRACT FROM AUTHOR]

Background Cardiovascular disease ( CVD) is the main cause of death in people with abdominal aortic aneurysm ( AAA). There is little evidence that screening for AAA reduces all-cause or cardiovascular mortality. The aim of the study was to assess whether subjects with a small or medium AAA (3·0-5·4 cm), without previous history of clinical CVD, had raised levels of CVD biomarkers or increased total mortality. Methods This prospective study included subjects with a small or medium AAA and controls, all without a history of clinical CVD. CVD biomarkers (high-sensitivity C-reactive protein, hs- CRP; heart-type fatty acid-binding protein, H- FABP) were measured, and survival was recorded. Results Of a total of 815 people, 476 with an AAA and 339 controls, a cohort of 86 with small or medium AAA (3-5·4 cm) and 158 controls, all with no clinical history of CVD, were identified. The groups were matched for age and sex. The AAA group had higher median (i.q.r.) levels of hs- CRP (2·8 (1·2-6·0) versus 1·3 (0·5-3·5) mg/l; P < 0·001) and H- FABP (4·6 (3·5-6·0) versus 4·0 (3·3-5·1) µg/l; P = 0·011) than controls. Smoking was more common in the AAA group; however, hs- CRP and H- FABP levels were not related to smoking. Mean survival was lower in the AAA group: 6·3 (95 per cent confidence interval (c·i.) 5·6 to 6·9) years versus 8·0 (7·6 to 8·1) years in controls ( P < 0·001). Adjusted mortality was higher in the AAA group (hazard ratio 3·41, 95 per cent c·i. 2·11 to 9·19; P < 0·001). Conclusion People with small or medium AAA and no clinical symptoms of CVD have higher levels of hs- CRP and H- FABP, and higher mortality compared with controls. They should continue to receive secondary prevention against CVD. [ABSTRACT FROM AUTHOR]

Highlights: [•] We applied large strain machining on aluminum 6061-O samples. [•] Temperature effect on microstructure evolution was considered. [•] Inverse relation between hardness and strain versus cutting velocity was observed. [•] Contact length parameter significantly influences the final microstructure. [•] Production of continuous ultra-fine grain chip even in high velocities. [Copyright &y& Elsevier]

In this article, we present the uniform convergence analysis and accuracy estimation of hybrid functions (HFs) method for finding the solution of nonlinear Volterra and Fredholm integral equations. The properties of HFs which consist of block-pulse functions (BPFs) and Legendre polynomials are used to reduce the solution of nonlinear integral equations to the solution of algebraic equations. The superiority and accuracy of the HFs method to BPF and Legendre polynomial methods are illustrated through some numerical examples. [ABSTRACT FROM PUBLISHER]

A three-generation resource population was developed using two distinct Japanese quail strains, wild and white, to map quantitative trait loci underlying hatching weight and growth traits. Eight pairs of white and wild birds were crossed reciprocally and 34 F1 birds were produced. The F1 birds were intercrossed to generate 422 F2 offspring. All of the animals from three generations (472 birds) were genotyped for eight microsatellite markers on chromosome 1. Liveweight data from hatch to 5 weeks of age were collected on the F2 birds. Quantitative trait loci (QTL) analysis was conducted applying the line-cross model and the least-squares interval mapping approach. The results indicated QTL affecting hatching weight and several growth related traits on chromosome 1. The F2 phenotypic variance explained by the detected additive QTL effects ranged from 1.0 to 3.7 for different traits. Modelling both additive and dominance QTL effects revealed additional QTL with significant dominance mode of action affecting pre-slaughter weight. However, there was no evidence for imprinting (parent-of-origin) effects. The variance due to the reciprocal cross effect ranged between 3.0 and 19.1% for weight at 1 week of age and hatching weight, respectively. Genetic mapping of loci underlying economic traits in Japanese quail is of great interest both for biologists and animal breeders. The results of this study indicated significant regions on chromosome 1 affecting hatching weight and growth-related traits. These results pave the way for future gene discovery in Japanese quail as an animal model species. [ABSTRACT FROM AUTHOR]

An approximation method is developed for the solution of high-order non-linear Volterra-Fredholm integro-differential (NVFID) equations under the mixed conditions. The approach is based on the orthogonal Chebyshev polynomials. The operational matrices of integration and product together with the derivative operational matrix are presented and are utilized to reduce the computation of Volterra-Fredholm integro-differential equations to a system of non-linear algebraic equations. Numerical examples illustrate the pertinent features of the method. [ABSTRACT FROM AUTHOR]

Abstract: Orthogonal Chebyshev polynomials are developed to approximate the solutions of linear and nonlinear Volterra integral equations. Properties of these polynomials and some operational matrices are first presented. These properties are then used to reduce the integral equations to a system of linear or nonlinear algebraic equations. Numerical examples illustrate the pertinent features of the method. [Copyright &y& Elsevier]

Abstract: An efficient method based on the Legendre wavelet approach is proposed for approximate the solution of Fredholm integral equations of the first kind. The continues Legendre wavelets constructed on [0,1] are utilized as a basis in Galerkin method to reduce the solution of linear integral equations to a system of algebraic equations. For solving this system, we use the CG method. Furthermore, we suggest a convergence analysis and error estimation for this method. For showing efficiency of method some test problems, for which the exact solution is known, are considered. [Copyright &y& Elsevier]

The effects of stress relief on the magnetic characteristics of Fe-based metallic glass (MG) ribbons are investigated under external stress through various annealing treatments. We found that long-time annealing treatments benefit for making softer magnetic MGs under applied bending stress. We show that the irreversible domain wall movement region and the irreversible domain wall rotation region in the M-H curve represent the stress relief, which can be well reflected by the demagnified magnetic anisotropy. The magnetic coercivity and effective permeability variations in the lower frequency regime also represent the stress relief state. These observations have implications for understanding the relationship between the stress relief, microstructure change, and magnetic softness in magnetic MGs and might be helpful for the performance improvement of the ferromagnetic glassy materials. [ABSTRACT FROM AUTHOR]

Coincidence Doppler Broadening Spectroscopy of positron annihilation radiation is developed using high energy gamma-rays instead of standard positron source for defect assessment in thick samples. A 2.5 MeV proton beam of a Van de Graaff accelerator is used to generate high-energy gamma-ray through 19 F p , α γ 16 O nuclear reaction. The collimated gamma-ray is used to generate positron inside the sample. The performance of the technique to support the positron annihilation spectroscopy experiment is evaluated by investigation of the defect evolution of five low-carbon steel samples preloaded during the uniaxial tension test. The variation of the S-parameter versus strain is investigated and discussed considering the engineering stress-strain curve of the samples. Moreover, the advantages and limitations of the technique over the conventional CDBS are discussed. The developed spectrometer provides a systematic approach for the defect assessment in thick high-Z elements samples. [ABSTRACT FROM AUTHOR]

Structural heterogeneity of metallic glass is critical in cryogenic rejuvenation but chemical heterogeneity is seldom explored. Here we show that cryogenic rejuvenation of a nominal La 60 Al 25 Ni 15 (at.%) metallic glass can be enabled with little impurities of Ce and Fe inside the material. Besides, these impurities can significantly enlarge the plastic strain conveyed by the material in bending. In addition, the heterogeneous structure is observed in the sample containing these chemical heterogeneities. Although the glass forming ability of the metallic glass is worsened, our study highlights the impact of chemical heterogeneity on the cryogenic rejuvenation of metallic glasses. Image 1 • The importance of chemical heterogeneity on cryogenic rejuvenation of metallic glasses. • A little impurity can enable energy-increase in La 60 Al 25 Ni 15 (at.%) metallic glass. • Plasticity-enhancement of rejuvenated glass. [ABSTRACT FROM AUTHOR]

Abstract: Due to the organ shortage, many renal transplantation centers attempt to increase the donor pool by using non–heart-beating donors (NHBDs). These kidneys are generally regarded as “marginal” grafts. Many centers do not consider transplantation from an NHBD with a history of diabetes as it is a more suboptimal donor. We began our NHBD program in 1998 and have performed 5 renal transplants from diabetic NHBDs. Viability testing identified kidneys suitable for single or dual transplantation. Although kidneys from brain stem dead donors with diabetes have been used successfully, our data suggested that kidneys from diabetic NHBDs can also be used although we still need long-term results. [Copyright &y& Elsevier]

Abstract: To deal with the increasing gap between organ demand and supply for kidney transplantation, many centers have started to use non–heart-beating (NHB) donors. When we initiated our program to utilize kidneys from such donors in 1998, we had no protocol for the maximal agonal period. This however was audited in retrospect. Our current wait time is now a maximum of 5 hours. Concern has been expressed in the past about possible deterioration in the quality of the organs with a protracted agonal time. We aimed in this study to examine the effect of prolonging agonal period on the quality of kidneys retrieved from Maastricht category III donors: A total of 40 kidneys were transplanted from 29 category III donors between 1998 and 2004. Eleven kidneys had donor agonal times of >5 hours; the remainder, agonal times <5 hours. Both groups were matched for donor and recipient factors. The mean glomerular filtration rates at 12 months for <5 hours versus >5 hours agonal time were 43.8 ± 4.4 versus 49.8 ± 5.8, respectively (P = .24) and at 24 months, 46.83 ± 8.99 versus 37.67 ± 3.85, respectively (P = .24). In conclusion, intermediate graft function is comparable to ones with shorter agonal time, although we await long-term results. [Copyright &y& Elsevier]

Abstract: Kidneys transplanted from non-heart-beating donors (NHBD) are generally regarded as marginal or extended criteria grafts due to the associated period of warm ischemia. The most prolonged periods occurring in the category II (uncontrolled) donor. This potential for injury can adversely affect the glomular filtration rate (GFR), which in severe cases results in primary nonfunction. Viability testing can identify a group of kidneys that, although unsuitable for solitary transplantation, may be considered for dual transplant. This retrospective study examined a series of 11 dual renal transplants, comparing 3- and 12-month GFR outcome data with 81 single NHBD transplants. The mean GFR at 3 months in the dual group was 47.6 and at 12 months was 48.6. In the single group the GFR at 3 months was 40.6 and at 12 months was 41.9. Thus using viability testing to identify NHBD kidneys suitable for dual transplant appears reliable and predictable. [Copyright &y& Elsevier]

Abstract: Kidneys transplanted from non-heart-beating donors (NHBDs) have been exposed to varying degrees of ischemic damage after death. Category III donors have invariably been managed, treated, and investigated in a hospital setting prior to arrest and death. Some therefore exhibit evidence of renal dysfunction and even acute renal failure (ARF) before death. Many surgeons would regard a NHBD with pre-arrest evidence of ARF as too marginal for renal transplantation. This retrospective study examines five Maastricht category III NHBD donors with evidence of pre-arrest ARF. We compare 3- and 12-month GFR outcome data from the nine resulting transplants with 40 category III NHBD transplants with normal pre-arrest renal function. The mean GFR at 3 months was 45.4 and 43.8 for the ARF and normal group, respectively. At 12 months the GFR was 42.2 and 44.7 in the ARF and normal groups, respectively. Thus evidence of ARF pre-arrest does not preclude successful category III NHBD renal transplantation. [Copyright &y& Elsevier]

Abstract: The shortage of donor kidneys for renal transplantation is becoming more severe as the gap between the number of patients waiting for renal transplantation and the number of cadaveric organs available continues to widen. Therefore, many centres have started using non-heart-beating (NHB) donors. There was no clear plan for maximal duration of agonal period in Maastricht category NHB donors after withdrawal of treatment in Newcastle. This withdrawal has been audited in retrospect. Our current wait time is now a maximum of 5 hours; however, previously there have been some considerably longer periods. Concern has always been expressed about poor quality with protracted periods. Nonuse in this review of 58 kidneys can be expressed against time: 0 to 2 hours 13%, 2 to 5 hours 33%, and >5 hours 45%. Therefore, though the nonuse rate was significantly different between 0 to 2 hours and >5 hours (P < .05, chi-square), there were 16 transplants performed with kidneys >2 hours and 12 transplanted >5 hours. In conclusion, although good usable kidneys can still be used with protracted withdrawal, there are considerable logistical difficulties with our 5-hour cut-off, which means that one third of potential kidneys will not be utilized. [Copyright &y& Elsevier]

The article discusses a conference paper about the link between genetic variation and aggression from monoamine oxidase A (MAOA) that was presented at the International Conference for Healthcare & Medical Students held in Dublin, Ireland from October 11-12, 2013. It examines the impacts of allelic variation of the MAOA gene on criminal behaviour. It also highlights the involvement of biological, environmental and social factors in criminal behaviours.

Here, we report primary and secondary nanoscale phase separation in Cu 46 Zr 46 Al 8 (at.%) bulk metallic glass (BMG) achieved by altering the casting temperature. The BMG rods were cast by using the melting currents of 160 A and 220 A which provide, respectively, higher and lower cooling rates. The transmission electron microscopy and energy-dispersive X-ray analysis revealed that the higher cooling rate conditions brings a primary phase separation of nanoscale Cu-rich amorphous regions which are evenly dispersed in the Cu-depleted amorphous matrix phase. However, lower cooling rates results in a bimodal microstructure comprising coarsened primary-separated nanograins and very fine secondary-separated nanograins throughout the amorphous matrix containing nanocrystals of smaller than 5 nm in size. This unique microstructure developed under lower cooling rates gives lower relaxation enthalpy, higher short-range ordering, and enhanced strain-hardening. Our study emphasizes the significant role of casting temperature on controlling the morphology of nanoscale phase separation in BMGs. • The effects of quenching conditions on the phase separation of Cu 46 Zr 46 Al 8 (at.%) BMG rods were studied. • Higher melt temperature (lower cooling rate) decreases relaxation and crystallization enthalpies. • Primary and secondary phase separation was observed at lower cooling rate conditions. • The underlying mechanism for the observed phase separations was delineated. [ABSTRACT FROM AUTHOR]

In this paper, we analyse the iterated collocation method for the nonlinear Urysohn operator equation x=y+K(x) with K a singular kernel. The paper extends the study [H. Kaneko, R.D. Noren, and P.A. Padilla, J. Comput. Appl. Math. 80 (1997), pp. 335-349] in which the convergence of the iterated collocation method for Urysohn equations is considered. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, mechanical properties and deformation behavior of Al/Al7075, two-phase material were investigated. The two-phase materials were fabricated by mixing commercially pure Al powder with Al7075 chips and consolidating the mixture through hot extrusion process at 500°C. Mechanical properties and deformation behavior of the fabricated samples were evaluated using tensile and compression tests. A scanning electron microscope was used to study the fracture surface of the samples including different amount of Al powder, after they were fractured in tensile test. The results of the tensile and compression tests showed that with decreasing the amount of Al powder, the strength increases and ductility decreases. Calculation of work hardening exponent (n) indicated that deformation behavior does not follow a regular trend. In a way that the n value was approved to be variable and a strong function of strain and Al powder wt% of the sample. The results of the fractography studies indicate that the type of fracture happened changes from completely ductile to nearly brittle by decreasing the wt% of Al powder from 90% to 40%. [Copyright &y& Elsevier]

Abstract: Graft thrombosis is one of the most devastating complications of transplantation. In obtaining consent prior to transplant, it is useful to share potential risk factors with the recipient. In order to do this, we explored the impact of different risk factors that could contribute to this complication. Using multivariate analysis we found that neither multiple vessels nor vascular injury had a bearing on the risk of graft thrombosis but atheroma did (P < .02). [Copyright &y& Elsevier]

Abstract: Non-heart-beating donor kidneys (NHBD) are being used to increase the donor pool due to the scarcity of cadaveric heart beating donors (HBD). We evaluated the long-term outcomes of renal transplantation using NHBD kidneys, comparing the first 100 NHBD kidneys transplanted at our facility to the next consecutive cadaveric HBD kidneys for graft survival, recipient survival, and quality of graft function. Recipient survival (P = .22) and graft survival (P = .19) at 6 years did not differ between recipients of NHBD (83%, 80%) and HBD (89%, 87%) kidneys. Quality of graft function using the mean glomular filtration rates were significantly lower in the NHBD group up to 3 months following discharge (41 ± 2 vs 47 ± 2, P = .007) but were then comparable up to 6 years following transplantation (43 ± 5 vs 46 ± 4, P = .55). [Copyright &y& Elsevier]