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The quantitative concentration of alloying elements in low-alloyed copper alloys is an important factor in forming electrical and mechanical characteristics. It is known that severe plastic deformation is accompanied by both a substantial refinement of the structure and changes in the kinetics of phase transformations during the deformation and the post-deformation thermal treatment. This paper presents the results of a comparative analysis of the Cu–0.2Cr and Cu–1.1Cr alloys subjected to equal-channel angular pressing at room temperature. The analysis was performed for the grain structure, solid solution, and second-phase particles using transmission electron microscopy, scanning electron microscopy, X-ray crystal analysis, and the small-angle diffraction method. It was found that the level of structure refinement and mechanical characteristics after equal-channel angular pressing was almost the same for both studied alloys. Post-deformation aging of the Cu–0.2Cr alloy leads to the development of polygonization and re-crystallization within it. The aging of the Cu–1.1Cr alloy shows a better thermal stability than that of the Cu–0.2Cr alloy. In the Cu–1.1Cr alloy, after aging, in comparison with Cu–0.2Cr, a denser-packed ensemble of fine particles with an average size of 54 ± 2 nm is formed. In this case, the average size of fragments is 270 ± 15 nm and the ultimate tensile strength reaches 485 MPa.

A growing interest in wrought magnesium alloys has been noticed recently, mainly due to development of various SPD (severe plastic deformation) methods that enable significant refinement of the microstructure and – as a result – improvement of various functional properties of products. However, forming as-cast magnesium alloys with the increased aluminum content at room temperature is almost impossible. Therefore, application of heat treatment before forming or forming at elevated temperature is recommended for these alloys. The paper presents the influence of selected heat treatment conditions on the microstructure and the mechanical properties of the as-cast AZ91 alloy. Deformation behaviour of the as-cast AZ61 alloy at elevated temperatures was analysed as well. The microstructure analysis was performed by means of both light microscopy and SEM. The latter one was used also for fracture analysis. Moreover, the effect of chemical composition modification by lithium addition on the microstructure of the AZ31-based alloy is presented. The test results can be helpful in preparation of the magnesium-aluminum alloys for further processing by means of SPD methods.

Equal channel angular rolling (ECAR) is a severe plastic deformation (SPD) process in order to achieve ultrafine-grained (UFG) structure. In this paper, the mechanical properties of ECAR process using artificial neural network (ANN) and nonlinear regression have been illustrated. For this purpose, a multilayer perceptron (MLP) based feed-forward ANN has been used to predict the mechanical properties of ECARed Al6061 alloy sheets. Channel oblique angle, number of passes and the route of feeding are considered as ANN inputs and tensile strength, elongation and hardness are considered as the outputs of ANN. In addition, the relationship between input parameters and mechanical properties were extracted separately using nonlinear regression method. Comparing the outputs of models and experimental results shows that models used in this study can estimate the mechanical properties appropriately. Where, the performance of ANN model is better than the correlations to predict mechanical properties. Finally, the developed outputs of trained neural network model are used to analyze the effects of input parameters on tensile strength, elongation and hardness of ECARed Al6061 alloy sheets. The results showed that the ANN model, without highly expensive tests and experiments, is an efficient tool to predict the mechanical properties of ECARed Al6061 sheets.

Although maladaptive sensory processing has been observed among individuals with persistent heightened anxiety, it is unclear if difficulties processing sensory input early in life lead to anxiety disorders in adulthood and what mechanisms would drive this progression. In a transdiagnostic clinical sample of 231 adults characterized by heightened difficulties with emotion regulation, the present study sought to examine whether: (a) childhood sensory processing disorder (SPD) symptoms predict an increased probability of an anxiety disorder diagnosis in adulthood; and (b) difficulties with emotion regulation and adult SPD symptoms mediate this relationship. Participants were administered the Structured Clinical Interview for Axis-I disorders and self-reported symptoms of SPD experienced in childhood and adulthood. Results suggested that childhood SPD symptoms were significantly associated with a higher likelihood of a lifetime anxiety disorder diagnosis. Difficulties with emotion regulation fully mediated the relationship between childhood SPD and (a) any anxiety disorder in adulthood and, specifically (b) current generalized anxiety disorder (GAD). Further, we found evidence for a candidate model accounting for the relationship among childhood SPD, adulthood SPD, difficulties with emotion regulation, and anxiety disorders in adulthood. Specifically, our data indicated that high symptoms of SPD in childhood may lead to high SPD symptoms in adulthood, which then lead to high emotion dysregulation, ultimately conferring vulnerability for an anxiety disorder diagnosis. Taken together, these findings provide preliminary evidence for how sensory processing impairments in childhood may relate to anxiety through difficulties regulating emotion regulation.

Background: Supply, processing, and distribution (SPD) model is sparingly used in hospitals in China. We evaluated its effects on the management efficiency, quality control, and operating costs of medical consumables (MCs) in the clinical nursing surroundings in a single Chinese hospital-Anhui Provincial Hospital from 2014 to 2015. Methods: Amount-based packages (ABP) and procedure-based packages (PBP) models were created. They were introduced the use of quick response (QR) code scanning for using in clinical nursing departments (CNDs). Questionnaires were prepared by referring to previous literature and using Delphi method repeatedly, further discussed and formalized. Partial results of the formal questionnaire were analyzed using SPSS. Results: Frequency of MCs claims reduced without any requirements of MCs in 70% of CNDs. Average time spent on the inventory per week decreased and the time required to procure MCs reduced. Moreover, the average satisfaction score with MCs management increased, reaching 100%. Average space occupied by MCs decreased significantly, reducing by 1.2444m3. Overall, 100% of the respondents concluded that the management of MCs improved effectively and the inventory turnover rate had accelerated. The cost of MCs decreased by 15% with more than 10% increase in in-hospital amount, and the average daily cost of MCs also showed decrease. Conclusion: SPD can improve the efficiency of MCs management in CNDs, reducing medical risks and disputes, saving hospital operating costs, and decreasing capital occupation.

En este estudio, se evaluó el efecto de la técnica de presión calibrada, sobre las propiedades mecánicas y la microestructura de probetas de acero inoxidable AISI 316L, hasta lograr una deformación equivalente de ε~4,64. Dicha evaluación se realizó antes y después de aplicar la deformación plástica. Los resultados obtenidos mostraron un aumento en la dureza, el límite elástico y la resistencia útima a la tracción debido a la reducción del tamaño de grano, el maclado de mecánico y la transformación martensítica.

Background: Synthetic patient data (SPD) generation for survival analysis in oncology trials holds significant potential for accelerating clinical development. Various machine learning methods, including classification and regression trees (CART), random forest (RF), Bayesian network (BN), and conditional tabular generative adversarial network (CTGAN), have been used for this purpose, but their performance in reflecting actual patient survival data remains under investigation., Objective: The aim of this study was to determine the most suitable SPD generation method for oncology trials, specifically focusing on both progression-free survival (PFS) and overall survival (OS), which are the primary evaluation end points in oncology trials. To achieve this goal, we conducted a comparative simulation of 4 generation methods, including CART, RF, BN, and the CTGAN, and the performance of each method was evaluated., Methods: Using multiple clinical trial data sets, 1000 data sets were generated by using each method for each clinical trial data set and evaluated as follows: (1) median survival time (MST) of PFS and OS; (2) hazard ratio distance (HRD), which indicates the similarity between the actual survival function and a synthetic survival function; and (3) visual analysis of Kaplan-Meier (KM) plots. Each method's ability to mimic the statistical properties of real patient data was evaluated from these multiple angles., Results: In most simulation cases, CART demonstrated the high percentages of MSTs for synthetic data falling within the 95% CI range of the MST of the actual data. These percentages ranged from 88.8% to 98.0% for PFS and from 60.8% to 96.1% for OS. In the evaluation of HRD, CART revealed that HRD values were concentrated at approximately 0.9. Conversely, for the other methods, no consistent trend was observed for either PFS or OS. CART demonstrated better similarity than RF, in that CART caused overfitting and RF (a kind of ensemble learning approach) prevented it. In SPD generation, the statistical properties close to the actual data should be the focus, not a well-generalized prediction model. Both the BN and CTGAN methods cannot accurately reflect the statistical properties of the actual data because small data sets are not suitable., Conclusions: As a method for generating SPD for survival data from small data sets, such as clinical trial data, CART demonstrated to be the most effective method compared to RF, BN, and CTGAN. Additionally, it is possible to improve CART-based generation methods by incorporating feature engineering and other methods in future work., (© Ippei Akiya, Takuma Ishihara, Keiichi Yamamoto. Originally published in JMIR Medical Informatics (https://medinform.jmir.org).)

In this study, a novel severe plastic deformation method, named as thin-walled open channel angular pressing (TWO-CAP), was developed and applied to AZ31 magnesium alloy beams in U-type cross-sectional shape. First of all, the principles of the method with all parameters were determined, and the analytical model of the system was generated, and then the study was supported with the numerical analysis. Then, a proper experimental setup was established by considering theoretic outputs. After that, AZ31 magnesium alloy specimens were machined from bulk material in U-type shape as to fit the die channel, and then these specimens were annealed and pressed along the TWO-CAP die. Following the experimental studies, the specimens were tested in order to define the changes in mechanical and microstructural properties. In this stage, the tension test and hardness test were applied to determine the mechanical properties, while optical microscope, scanning electron microscope, energy dispersive spectrometry, X-ray diffraction, and transmission electron microscope analyses were applied to see the changes in microstructure. As a result, an improvement on strength, hardness, and toughness was observed depending on the changes on the microstructure and grain refinement due to the large plastic deformation. [ABSTRACT FROM AUTHOR]

The nonlinear autoregressive network with exogenous inputs (NARX) is a recurrent dynamic neural architecture, which is commonly used for input–output modeling of nonlinear dynamical systems. Due to the lack of accurate mathematical model for the performance analysis on surge protective devices (SPDs), with the input of fast rising time electromagnetic pulse (FREMP), the NARX neural network is employed to predict the response characteristics of SPD in this paper. In order to verify the feasibility of this method, SPD test system is set up according to IEC 61000-4-24. The results show that the response curve estimated by the proposed model is in good agreement with experimental results, especially the waveform parameters such as response time, pulse peak, and residual voltage. The good forecasting performance of the network suggests that the NARX model used in this paper has good generalization ability. Moreover, with less measured data it can predict the response of the SPD under different voltage levels that were not yet measured. [ABSTRACT FROM AUTHOR]

This research is a numerical study of the effect of the constrained groove pressing (CGP) process and its impact on a thermoplastic polymer (polyamide PA 66). A simulation is performed using a finite element tool. The effect of the process conditions and the tool geometry on the mechanical properties is noted. The results are significant, the equivalent strain and Von Mises stress have been progressed accordingly to the number of cycles and the tool geometry. Concluding remarks on the alteration of the microstructure have been proclaimed at the end of this paper. [ABSTRACT FROM AUTHOR]

Copyright of Espacio, Tiempo y Forma: Serie V, Historia Contemporánea is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a study performed on time, frequency, and energy correlations of transient voltages generated by the cloud to cloud discharges. It revealed that the energy embedded in transient voltages have been lumped over few segments of time domain voltage profile than uniquely scattering over the time span. The study further determined that the energy concentration becomes higher in and around the vicinity of the time domain voltage maxima or minima, and such high energy-concentrated segments confined to a minute time span in comparison to the total time span of the transient voltage. The study also established that there is a small time lead or lag between the time domain voltage maxima or minima and the time of energy maximize. Moreover, the analysis deduced that the time lead or time lag phenomenon, is not sensitive to the orientation of the time domain voltage profile, but fuelled by the pulse type. The response time of surge protective devices can become crucial if the stipulated clamping voltages of the protection devices fall close to local peaks of the transient voltages. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polyamines and SICS (Manganese + Boron) are popular chemical compounds using for the improvement of qualitative traits of pear and apple fruits. In the present study, we investigated the effects of these compounds on self- and open-pollinated shoots of pear trees. Treatments included putrescine (Put) (0.1 and 0.25 mM), Spermine (Spm) and Spermidine (Spd) (0.05 and 0.25 mM), and SICS (1 and 2 mg/L) solely or along with coverage cotton bags (CCB) in order to prevent cross and open pollination. Based on the results, treatment of Put (0.1 mM) alone showed the highest oxidative material index (P < 0.05). Treatments containing Spd (0.25 mM) both solely and with cotton coverage, Spm (0.05 and 0.25 mM) both solely and with cotton coverage, SICS (1 mg/L) alone, and SICS (2 mg/L) both alone and with cotton coverage showed the lowest content of oxidative material index in comparison with control (P < 0.05). Spd (0.05 mM) alone increased the anthocyanin content (P < 0.05). Treatment of SICS (2 mg/L) alone had higher content of (TSS/TA or Index of Maturity) (P < 0.05). SICS at 2 mg/L with cotton coverage, Spd at 0.05 mM alone, and Spd and Spm (0.05 and 0.25 mM) with cotton coverage showed the highest rate of pH (P < 0.05). [ABSTRACT FROM AUTHOR]

Although maladaptive sensory processing has been observed among individuals with persistent heightened anxiety, it is unclear if difficulties processing sensory input early in life lead to anxiety disorders in adulthood and what mechanisms would drive this progression. In a transdiagnostic clinical sample of 231 adults characterized by heightened difficulties with emotion regulation, the present study sought to examine whether: (a) childhood sensory processing disorder (SPD) symptoms predict an increased probability of an anxiety disorder diagnosis in adulthood; and (b) difficulties with emotion regulation and adult SPD symptoms mediate this relationship. Participants were administered the Structured Clinical Interview for Axis-I disorders and self-reported symptoms of SPD experienced in childhood and adulthood. Results suggested that childhood SPD symptoms were significantly associated with a higher likelihood of a lifetime anxiety disorder diagnosis. Difficulties with emotion regulation fully mediated the relationship between childhood SPD and (a) any anxiety disorder in adulthood and, specifically (b) current generalized anxiety disorder (GAD). Further, we found evidence for a candidate model accounting for the relationship among childhood SPD, adulthood SPD, difficulties with emotion regulation, and anxiety disorders in adulthood. Specifically, our data indicated that high symptoms of SPD in childhood may lead to high SPD symptoms in adulthood, which then lead to high emotion dysregulation, ultimately conferring vulnerability for an anxiety disorder diagnosis. Taken together, these findings provide preliminary evidence for how sensory processing impairments in childhood may relate to anxiety through difficulties regulating emotion regulation. [ABSTRACT FROM AUTHOR]

The political scene of the Federal Republic of Germany was traditionally recognised as extraordinarily stable. However, in the second decade of the 21st century the pace of changes in it has clearly quickened and they are reshaping it in the long term. The changes are conditioned by internal policy as well as global trends. In the author's opinion, the change in the German political scene does not take place rapidly but one can see the weakening of the left wing, the change of the party playing the role of a pivotal one, and probably the movement of Christian democracy towards the right wing under the pressure of radical tendencies. The growing difference between the socalled old and new federal states constitutes the biggest threat because the latter prove to be much more vulnerable to the influence of radically right movements. [ABSTRACT FROM AUTHOR]

Numerous methods are available to produce ultrafine grained material in severe plastic deformation (SPD) techniques. Accumulative roll bonding (ARB) is the most effective techniques to produce ultrafine grained composites with superior properties. The present investigation deals with the fabrication and comparison of Al 8011 composite by introducing various reinforcements such as Titanium carbide (TiC), Tungsten carbide (WC), Boron carbide (B4C) and Zirconium carbide (ZrC) through ARB technique by deforming plastically. Here, four specimens were prepared by incorporating 8 wt.% each of aforementioned carbide particles in Al matrix and compared with each other and characterized through advanced microscopic techniques such as SEM, EDAX, EBSD and TEM besides XRD. Furthermore, Vickers microhardness test and tensile test were conducted. The introduced reinforcement particles were found dispersed evenly throughout the surface by increasing the passes up to eight times. Among these reinforcements, Al 8011 – B4C composite has provided better strength than other composites due to following reasons: (i) high bonding of the interface between the sheets (ii) interlocking of B4C particles within the matrix (iii) higher hardness and strength. Hence, B4C reinforced Al composite claims greater significance for being recommended as an effective alternative for the aluminum material in load carrying applications. [ABSTRACT FROM AUTHOR]

The intent of this research was to determine if disability, body mass index (BMI), and serious psychological distress are associated withfood insecurity among residents of California. We conducted a secondary analysis of 61,274 Californians who responded to the California Health Interview Survey (CHIS) for 2013-2015. Disability was measured as having a physical, mental, or emotional condition. Serious psychological distress (SPD) was measured using the Kessler-6 Scale. Food security was measured as either beingfood secure, food insecure without hunger, or food insecure with hunger. The relationship between food insecurity status, disability, BMI, and SPD was assessed by means of multivariate logistic regression analyses using STATA/SE 14.2 for Windows. Of the 61,274 participants, 15.4 percent reported food insecurity. Among the food insecure, we found that individuals born outside of the US accounted for 54.8 percent, Latinos accounted for 60.1 percent, individuals on food stamps accounted for 24.7 percent, individuals with serious psychological distress accounted for 11.7 percent, disabled individuals accounted for 45.1 percent, and obese individuals accounted for 34.5 percent. From our multivariate logistic regression results, food insecurity was associated with being on food stamps (Odds Ratio [OR] 3.50), having serious psychological distress (OR 2.42), beingforeign born (OR 2.38), and being disabled (OR 1.92). The data showed food insecurity was prevalent among immigrants in California and it was significantly associated with Supplemental Nutrition Assistance Program (SNAP), SPD, disability, and being overweight or obese. These results show a need for culturally appropriate interventions targeting immigrants in California dealing withpsychological distress and other mental, physical, and emotional disabilities. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Papers of Electrical & Control Engineering Faculty Technical University of Gdansk / Zeszyty Naukowe Wydzialu Elektrotechniki & Automatyki Politechniki Gdanskiej is the property of Gdansk University of Technology, Faculty of Electrical & Control Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Non-edible parts of crustaceans could be a rich source of valuable bioactive compounds such as the carotenoid astaxanthin and peptides, which have well-recognized beneficial effects. These compounds are widely used in nutraceuticals and pharmaceuticals, and their market is rapidly growing, suggesting the need to find alternative sources. The aim of this work was to set up a pilot-scale protocol for the reutilization of by-products of processed shrimp, in order to address the utilization of this valuable biomass for nutraceutical and pharmaceuticals application, through the extraction of astaxanthin-enriched oil and antioxidant-rich protein hydrolysates. Astaxanthin (AST) was obtained using “green extraction methods,” such as using fish oil and different fatty acid ethyl esters as solvents and through supercritical fluid extraction (SFE), whereas bioactive peptides were obtained by protease hydrolysis. Both astaxanthin and bioactive peptides exhibited bioactive properties in vitro in cellular model systems, such as antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities (IA). The results show higher astaxanthin yields in ethyl esters fatty acids (TFA) extraction and significant enrichment by short-path distillation (SPD) up to 114.80 ± 1.23 µg/mL. Peptide fractions of

The present study was initiated to investigate the influence of an ECAP die on the microstructure evolution and properties of commercial Al-Mg aluminum alloy in as-cast state. To characterize microstructural features an optical microscope was used. The properties of the as processed and initial state material were evaluated based on the hardness measurements. It was found that the applied ECAP die has the meaningful influence on the microstructure as well as the properties of the material.

It is generally accepted that severe plastic deformation (SPD) has the ability to produce ultrafinegrained (UFG) and nanocrystalline materials in bulk. Recent developments in high pressure torsion (HPT) processes have led to the production of bimetallic composites using copper, aluminum or magnesium alloys. This article outlines a new approach to fabricate multilayered Ni-Ti nanocomposites by a patented SPD technique, namely, high speed high pressure torsion (HSHPT). The multilayered composite discs consist of Ni-Ti alloys of different composition: a shape memory alloy (SMA) Ti-rich, whose Mf > RT, and an SMA Ni-rich, whose Af < RT. The composites were designed to have 2 to 32 layers of both alloys. The layers were arranged in different sequences to improve the shape recovery on both heating and cooling of nickel-titanium alloys. The manufacturing process of Ni-Ti multilayers is explained in this work. The evolution of the microstructure was traced using optical, scanning electron and transmission electron microscopes. The effectiveness of the bonding of the multilayered composites was investigated. The shape memory characteristics and the martensitic transition of the nickel-titanium nanocomposites were studied by differential scanning calorimetry (DSC). This method opens up new possibilities for designing various layered metal-matrix composites achieving the best combination of shape memory, deformability and tensile strength.

This work considers the development and the application of combined severe plastic deformation (SPD) techniques to produce contact wire with an enhanced complex of physical, mechanical, and service properties used for high-speed railway lines. This type of processing can be used as an alternative to most conventional production methods, including rolling and drawing. The proposed technique is based on the combination of radial swaging and equal-channel angular pressing, bundled with the wire-forming process. Laboratory contact wire samples with an enhanced complex of physical, mechanical, and service properties were produced during physical experiments. The composition of processed alloy samples meets modern requirements for contact wires for high-speed railways. Ultimate tensile strength of 560 ± 20 MPa, electrical conductivity of 76 ± 2% IACS, and relative tensile elongation of 20 ± 2% are achieved through the formation of a band structure. Fragments of 300 ± 20 nm were formed inside strips with the precipitation of secondary phase particles of 20–100 nm along the fragment boundaries, mainly during the aging process.

In the present study, the wear behaviour of two aluminium alloys (AA-5754 and AA-5083) is analysed where these have been previously processed by severe plastic deformation (SPD) with equal channel angular pressing (ECAP). In order to achieve the objectives of this study, several disks made of these alloys are manufactured by isothermal forging from different initial states. The microstructures of the initial materials analysed in this study have different accumulated deformation levels. In order to compare the properties of the nanostructured materials with those which have not been ECAP-processed, several disks with a height of 6 mm and a diameter of 35 mm are manufactured from both aluminium alloys (that is, AA-5754 and AA-5083) isothermally forged at temperatures of 150 and 200 °C, respectively. These thus-manufactured disks are tested under a load of 0.6 kN, which is equivalent to a stress mean value of 18 MPa, and at a rotational speed of 200 rpm. In order to determine the wear values, the disks are weighed at the beginning, at 10,000 revolutions, at 50,000 revolutions and at 100,000 revolutions, and then the volume-loss values are calculated. This study was carried out using specific equipment, which may be considered to have a block-on-ring configuration, developed for testing in-service wear behaviour of mechanical components. From this, the wear coefficients for the two materials at different initial states are obtained. In addition, a comparison is made between the behaviour of the previously ECAP-processed aluminium alloys and those that are non-ECAP-processed. A methodology is proposed to determine wear coefficients for the aluminium alloys under consideration, which may be used to predict the wear behaviour. It is demonstrated that AA-5754 and AA-5083 aluminium alloys improve wear behaviour after the ECAP process compared to that obtained in non-ECAP-processed materials.

A magnesium alloy AZ31 as plate of dimensions (60 x 60 x 3) mm has been constrained groove pressed (CGP) four deformation passes (16 pressings) at 250 oC by simulation and experiments. On the basis of the analysis of calculation results about the deformation distribution in the alloy AZ31 workpieces, the mechanism for its microstructure evolution during the severe plastic deformation (SPD) process was partly clarified. On the other hand, deformation heterogeneity distribution developed in the workpieces by applying CGP caused the evolution of a non-uniform microstructure. The TEM microstructure analysis results provided clear evidence that across the plate both the banded deformed microstructure where dislocation cell structure and/or partially or fully recovered polygonized subgrain microstructure are present. The recovering dynamic and local polygonization process contributes significantly to the formation of ultra-fine materials (UFG) microstructure.

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) isolates of the clonal complex 398 are often resistant to a number of antimicrobial agents. Studies on the genetic basis of antimicrobial resistance in these bacteria identified SCCmec cassettes, various transposons and plasmids of different sizes that harbor antimicrobial resistance genes. While large plasmids that carry multiple antimicrobial resistance genes – occasionally together with heavy metal resistance genes and/or virulence genes – are frequently seen in LA-MRSA ST398, certain resistance genes are also associated with small plasmids of up to 15 kb in size. These small resistance plasmids usually carry only one, but in rare cases also two or three antimicrobial resistance genes. In the current review, we focus on small plasmids that carry the macrolide-lincosamide-streptogramin B resistance genes erm(C) or erm(T), the lincosamide resistance gene lnu(A), the pleuromutilin-lincosamide-streptogramin A resistance genes vga(A) or vga(C), the spectinomycin resistance gene spd, the apramycin resistance gene apmA, or the trimethoprim resistance gene dfrK. The detailed analysis of the structure of these plasmids allows comparisons with similar plasmids found in other staphylococci and underlines in many cases an exchange of such plasmids between LA-MRSA ST398 and other staphylococci including also coagulase-negative staphylococci.

Observations of refined microstructure of Commercial Purity titanium for applications in biomedical devices has been carried out. Refinement of titanium microstructure has been performed in process with complex strain scheme. Materials investigated in this work were: Commercial Purity titanium grade 2 and grade 4. Samples of as received materials were subjected to plastic deformation in complex loading process of extrusion combined with oscillation twisting (KoBo extrusion). Both types of samples were deformed in single step of extrusion, in temperature of 450 °C, with extrusion ratio 19.14 and 12.25 for grade 2 titanium and grade 4 titanium, respectively. Initial mean grain diameter for both types of materials was approximately 30 μm. Samples were investigated by means of crystal orientation microscopy. In both cases considerable microstructure refinement has been observed. Microstructures of deformed samples are heterogenous and consist of both elongated and fine equiaxed grains. Elongated grains (lamellae) are separated by High Angle Grain Boundaries and feature internal structure with subgrains and dislocation walls. Grain refinement is stronger in material with higher extrusion ratio and mean grain diameter in this case is equal to 1.48 μm compared to 8.07 μm. in material with lower extrusion ratio. Mean misorientation angle (24° and 27° for grade 4 and grade 2 titanium) indicates high fraction of HAGBs in microstructures of KoBo deformed samples. Misorientation fluctuations inside grains have been analyzed and distinct curvature of crystal lattice have been observed. Hardness of samples after plastic deformation increased from 174.6±3.4 and 234.9±3.5 to 205.0±3.2 and 251.2±2.2 for titanium grade 2 and grade 4 respectively.

A review on the microstructural evolution in magnesium alloys during severe plastic deformation waspresented. The challenges deserved to achieve ultrafine/ nanostructured magnesium were discussed.The characteristics of the processed materials are influenced by three main factors, including i)difficult processing at low temperatures, ii) high temperature processing and the occurrence ofdynamic recrystallization and grain growth processes, and iii) a combined effect of grain refinementand crystallographic texture changes. Reviewing the published results indicate that there are twopotential difficulties with severe deformation of magnesium alloys. First, it is very hard to achievehomogeneous ultrafined microstructure with initial coarse grains. The second is the dependency ofmicrostructure development on the initial grain size and on the imposed strain level. It was clarifiedthat different grain refining mechanisms may be contributed along the course of multi-pass severedeformation. It was clarified that discontinuous recrystallization takes places during the first stages ofdeformation, whereas continuous refinement of the recrystallized grain may be realized at consecutivepasses. Shear band formation as well as twinning were demonstrated to play a significant role in grainrefinement of magnesium alloy. Also, the higher the processing temperature employed the morehomogeneous microstructure may be achieved with higher share of low angle grain boundaries.

Equal-channel angular pressing (ECAP) combined with the Conform process provides a solution for the continuous production of ultrafine-grained materials. In the present study finite element method was executed to investigate the effects of die channel angle and friction on the strain homogeneity and the required torque in ECAP-Conform process. Deformation behaviour of Al 6061 wires was analyzed by using the ABAQUS/Explicit software. Finite element analyses by considering different channel angles (90ᵒ, 100ᵒ and 110ᵒ) and various friction conditions of 0.2, 0.3 and 0.4 were surveyed. The results revealed two distinct trends in which by increasing the channel angle among 90ᵒ to 110ᵒ, the amount of induced plastic strain through the wire reduced about 40%. Also required processing torque was decreased about50%. In addition more homogeneity was observed in higher angle values. The results regarding to equivalent strain, obtained from FE analyses, showed a good agreement with previous studies. Eventually plastic strains and required torque were increased about 8% and 12% when friction coefficient raised between (0.2-0.4).

Analysis of the results of the microstructure and the mechanical properties change in AA1050 aluminum alloy of technical purity processed using ECAP (Equal Channel Angular Pressing) and KoBo deformation methods are presented in the paper.. ECAP process was performed according to Bc scheme in the range from 1 up to 10 passes. Changes of microstructure were analyzed using scanning electrone microscope equipped with electron backscattered diffraction (EBSD) system. Microstructure and fraction of high-angle grain boundaries in KoBo processed samples were similar to those observed in ECAP processed samples after four passes. The most significant microstructure refinement was observed in ECAP processed sample submitted to 10 passes. In ECAP method the systematic increase of mechanical properties was observed along with increase of deformation degree.

RESUMOA produtividade de grãos do arroz é resultante da interação entre o ambiente e o cultivar utilizado. Entre os fatores que influenciam essa produtividade estão o arranjo das plantas no campo e a adubação nitrogenada. O objetivo deste trabalho foi determinar os efeitos do espaçamento entre fileiras e da adubação nitrogenada na altura e acamamento de plantas, nos componentes de produção e produtividade e na qualidade industrial de grãos de arroz de terras altas, cultivado no sistema plantio direto. O experimento foi desenvolvido durante a safra agrícola 2010/2011, em condições de campo, no município de Selvíria, MS. O delineamento experimental foi em blocos completos casualizados, no esquema fatorial 2 x 4, com quatro repetições. Os tratamentos constaram de combinações entre os espaçamentos entre fileiras (0,35 e 0,50 m) e as doses de N aplicadas na semeadura (0, 40, 80 e 120 kg ha-1). O menor espaçamento entre fileiras condicionou menor altura de plantas de arroz, maior número de panículas m-2, maior fertilidade das espiguetas e consequentemente maior produtividade de grãos de arroz. O incremento das doses de N na semeadura proporcionou maior altura e acamamento de plantas de arroz, ocasionando redução da produtividade e da massa hectolítrica de grãos da cultura. Espaçamento entre fileiras e nitrogênio não alteram a qualidade de grãos do arroz.

Highlights • Bistable metallic disks are manufactured by nanostructuring disks in a localized region. • Refined analytical models characterizing bistable behaviors are proposed. • Six transition types are found for bistable disks with different nanostructured regions. • Bistable metallic disks have good stabilities indicated by snapping forces. Abstract In contrast to conventional bistable disks manufactured using soft materials in spherical or domelike configurations, new bistable disks with designable configurations and high load-bearing capacities are proposed and developed based on the nanotechnology of surface mechanical attrition treatment (SMAT). A simple analytical model with explicit results, refined analytical models and numerical models are formulated to predict two stable configurations and study their transition processes. A simple algorithm that includes a confined equation for the formulated Ritz models is developed via a displacement control strategy to capture the full snapping processes of the bistable disks, which are actuated by a point force. The analytical models for the bistable disks identify various stable configurations and six transition strategies, and these are discussed systematically with respect to the design parameters. The ratio of the nanostructured region in the disks is found to have a critical influence on the stable configurations and the transition processes. The results from the experimentally manufactured bistable disks validate the obtained theoretical results. [ABSTRACT FROM AUTHOR]