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The evolution of grain boundary character distribution (GBCD) in the CoCrMo alloys processed by SLM and post-heat treatments (aging and solid solution) has been investigated by the electron backscatter diffraction (EBSD) and transmission electron microscope techniques. A high fraction of Σ3n (n = 1, 2, 3) grain boundaries and the corresponding clusters occur in the solid solution-treated samples at 1150 °C, which indicates GBCD optimization is somewhat realized. The coherent and incoherent Σ3 boundaries were distinguished via the single-section trace analysis method based on EBSD measurements. Σ3 boundaries in the SLMed and aged samples were determined as incoherent, while those in the solid solution-treated sample are coherent. Regular e precipitation did not occur in the solid solution-treated samples as in the aged samples. Instead, stacking fault bands associated with coherent Σ3 twin boundaries are dominant. It suggests that post-heat treatment has a significant influence on the GBCD, especially the Σ3 grain boundary characteristics.

Plasmodiophora brassicae is a biotrophic pathogen causing clubroots of cruciferous crops. The Brassica rapa accession T1-145 has an ability to produce small spheroid galls (SSGs), which represent neither a fully compatible interaction nor a complete resistance. To explore the defense response in SSGs induced by P. brassicae infection, global transcriptome profiling SSGs was performed at different time points. By comparing gene expression patterns, we identified many defense related genes. The first group included genes encoding receptor-like protein/kinases, such as cysteine-rich receptor-like protein kinases, receptor-like proteins, phloem intercalated with xylem/tracheary element differentiation inhibitory factor receptor (PXY/TDR), PXY-correlated 1, wall-associated kinases, nuclear shuttle protein-interacting kinase, lectin receptor-like kinases, and flagelin-sensitive 2, which might activate a basal defense. The second group involved robust effector-triggered immunity response genes such as resistance to leptosphaeria maculans 1B, constitutive shade-avoidance 1, target of avirulence B operation 1, ribosomal protein of the small subunit 6, resistance to Pseudomonas maculicola 1-interacting protein 4, enhanced disease resistance 2L, and recognition of Peronospora parasitica 13-like protein 4. The third group included genes encoding secondary cell wall formation related protein/s, a nodulin-like protein, a germin-like protein, a jacalin-related lectin, a defensin-like protein, tumor inhibitors, and sugars will eventually be exported transporter, which might contribute to quantitative resistance against P. brassicae. The gene expressions were the highest at the late stage of infection. To our knowledge, it is the first report on exploring defense response genes during SSG occurrence by a transcriptome analysis. Our data would provide useful information to further explore molecular mechanisms of the incomplete resistance.

Background Although work stress and impaired sleep are established risk factors for cardiovascular disease (CVD) among healthy individuals, their impact on hypertensive workers is largely unknown. Design Prospective cohort study design. Methods Hypertensive workers (N = 1959), derived from the population-based MONICA/KORA study in Southern Germany, who were free of any cardiovascular disease and diabetes were interviewed at baseline for work stress (high demand plus low control) and impaired sleep (difficulties falling asleep and/or maintaining sleep). Hazard ratios and 95% confidence intervals (CIs) were estimated by multivariate Cox proportional hazards models with adjustment for relevant covariates. Results During a mean follow-up of 17.8 years covering 34,900 person-years, 134 fatal CVD and 73 coronary heart disease (CHD) events were observed. In comparison to participants with low work stress and non-impaired sleep, participants with work stress (hazard ratio (HR) 1.56, 95% CI 0.81-2.98), or impaired sleep (HR 1.76, 95% CI 0.96-3.22) had an increased risk of CVD, while participants with both work stress and impaired sleep had the highest risk of CVD mortality (HR 2.94, 95% CI 1.18-7.33). Participants with both risk conditions had an absolute CVD mortality risk of 7.13 cases per 1000 person-years in comparison to 3.05 cases per 1000-person years in the reference group. Similar risk patterns were found for CHD mortality. Conclusions Our findings add a new piece of evidence that work stress together with impaired sleep increase risk of coronary and cardiovascular mortality in hypertensive workers.

Titanium alloy Ti-6Al-4V processed by electron beam melting (EBM) has a great potential for orthopedic and aerospace applications. However, the process induced porosity and microstructure anisotropy will have a significant impact on the material properties. This work has found that spherical and elongated pores with strong size effect are common characteristics for the as-EBM samples made with horizontal, diagonal, and vertical orientations w.r.t. the substrate. Furthermore, the major axis of the elongated pores is perpendicular to build direction for samples with different build orientations. The microstructure consists of columnar prior β grains delineated by grain boundary α and transformed α/β structures with α’ marteniste and basket weave morphology. Of note is that a high fraction of twin boundaries are prevalent in α (α’) phase. The configuration of the applied load w.r.t. the major axis of the elongated pores is the most significant influencing factor to mechanical properties, while the columnar prior β grain structure is secondary. Fractography reveals that microcracks tend to originate from elongated pores for cleavage fracture. In addition, the co-existing local terrace-like and shallow dimples are attributed to the intergranular crack propagation from the lamella α grain boundaries. Thus, the anisotropy of porosity and microstructure is of significance to enhance mechanical properties in process development.

Ceramic implants have superior performance due to the excellent wear resistance and biocompatibility. However, the poor machinability limits their applications. Plasma sprayed ceramic coating on the additively manufactured metal substrate not only provides a 3-dimensional conformal implant coating and but also forms a highly wear-resistant surface layer. In this paper, three types of ceramic coatings of Al2O3, ZrO2, and Al2O3–ZrO2 composite have been fabricated by atmosphere plasma spray on the CoCrMo alloy substrate prepared by selective laser melting (SLM). It has been found that the Al2O3–ZrO2 composite coating has better corrosion and wear resistance compared with the ceramic coating (Al2O3, ZrO2) and the CoCrMo substrate. The adhesion strength between the Al2O3–ZrO2 composite coating and the substrate reaches 238 MPa. In addition, the wear and corrosion resistance increase with wear progression for all the fabricated ceramic coatings. The highly dense microstructure, fewer microcracks, and the amorphous phases are deterministic factors responsible for the superior tribological and corrosion performance of the Al2O3–ZrO2 composite coating. The fabrication route has been proved very promising to manufacture high-performance implants with ceramic coating.

Laser additive manufacturing offers a unique way of tuning microstructure to improve alloy properties with a high degree of freedom by modifying the process parameters such as energy density. This work focuses on the energy density dependence of texture anisotropy and mechanical properties processed by selective laser melting (SLM) of IN 718 superalloy at different laser scanning speeds. It was found that strong columnar grains and 〈001〉 fiber texture become insignificant due to insufficient epitaxial growth as energy density decreases. The discrepancies in Taylor factor distributions induced by texture anisotropy are mainly responsible for the difference in tensile mechanical properties for samples built at different orientations. High Taylor factors lead to the increased strength of diagonally built testing samples. In addition, grain refinement enhances the strengthening effect as energy density decreases.

Background: Obesity and depression both individually contribute to the risk of Type II Diabetes (T2DM). The extent to which obesity can be set-off by depression is unknown.Methods: In a sample of 9340 participants followed for 15.4 years (79,372 person-years) from the prospective MONICA/KORA population-based cohort conducted in Southern Germany, we investigated the impact of obesity, defined as Body Mass Index (BMI) _a 30, and depression on the incidence of T2DM using Cox Proportional Hazards Regression.Results: The relative risk of T2DM was over 6 fold higher among obese participants in comparison to normal weight participants (HR 6.05; 95% CI 4.82 to 7.59; p

Electrical discharge machining (EDM) is advantageous in machining high strength and high-aspect-ratio components. However, EDM-induced thermal damage would detrimentally reduce fatigue life...

Select laser melting (SLM) is one of the practical metal additive manufacturing processes to fabricate complex structures. The inhomogeneous microstructure and high residual stress are typically resulted from a non-uniform melting and rapid solidification during a SLM process, which has the significant impact on part dimensional instability, corrosion resistance, and mechanical properties. The bulk of current research is limited to the general characterization of grain size, texture, and mechanical properties. However, grain boundary character distribution (GBCD) and its relationship with texture are yet to be understood. This study has shown that the preferred 〈110〉 along building direction and 〈100〉 along laser scanning direction were produced. The high density of low angle grain boundary (LAGB) can be an indicator of residual stress levels in the as-SLMed samples. The newly-developed ∑3, ∑9 and ∑27 grain boundaries were heavily populated, and the cluster of grains interfaced by ∑3n (n = 0, 1, 2…) was introduced at the expense of LAGB only at high recrystallization annealing (1150°C or over). The research results suggest that GBCD optimization be possible in the SLMed Inconel 625 alloy via suitable post annealing, which allows improving intergranular corrosion resistance and enhancing mechanical properties.

Selective laser melting (SLM) is a promising technology to manufacture functional (end-use) metal parts with complex geometry directly from CAD data. The process induced high tensile residual stress and part distortion due to the non-uniform heat input during a SLM process would detrimentally affect the part performance. However, it is extremely challenging to predict distortion of a practical SLMed part if each single track is taken into account by using the conventional modeling methods The complex multiphysics phenomenon such as fluid flow in the melt pool, phase transformation during cooling, and resulted anisotropic properties further complicate this issue. In this study, a temperature-thread multiscale modeling approach has been developed to effectively predict residual stress and part distortion of a twin cantilever. An equivalent body heat flux has been proposed from the microscale laser scan model and imported as the “temperature-thread” to the subsequent mesoscale layer hatch model. The hatched layer is then heated up by the equivalent body heat flux and used as a basic unit to build up the macroscale part in a layer by layer fashion. The thermal history and residual stress fields of the twin cantilever during the SLM process were simulated. The predicted cantilever distortion agrees with the measured data with a reasonable accuracy.

The unique thermal history of different metal additive manufacturing processes would have profound impacts on the resulting microstructure and material properties. However, few have conducted benchmark research on the impacts. This work provides a comprehensive benchmark comparison on microstructure, mechanical properties, and their underlying mechanisms in selective laser melting (SLM), electron beam melting (EBM), and mill-annealing of Ti–6Al–4V alloys. The results have shown that the SLMed and EBMed samples possess very fine acicular α′ martensite while the conventional mill-annealed ones have granular α phase. The SLMed samples exhibit the highest tensile and yield strength resulted from the combined effects of refined α’ martensite and high microscale residual stress. The lowest tensile and yield strength and intermediate elongation of the EBMed samples are attributed to the relatively high number of type-II pores and in-situ annealing for residual stress relief during the printing process. The mill-annealed samples have the highest elongation due to the fully dense structure, the negligible microscale residual stress, and favorable grain orientation. It is expected to improve the ductility of SLMed samples via appropriate post-annealing and enhance the strength of EBMed samples by reducing the number of type-II pores through process optimization. The fundamental differences in microstructure and properties are attributed to the unique thermal histories of the concerned processes.

The objective of this study was to determine the ileal digestible energy (IDE), ME, and MEn of rice, broken rice, and rice bran. The birds were fed a standard starter diet from day 0 to 14 and experimental diets from day 15 to 21 after hatching. A total of 336 birds were grouped by BW and assigned to 7 diets, each diet comprised 8 replicates with 6 birds per replicate. The diets comprised a reference diet (RD) and 6 test diets (TD). The TD contained 2 levels of rice, broken rice or rice bran that partly replaced the energy sources in the RD at 120 or 240 g/kg (rice and broken rice) or 150 or 300 g/kg (rice bran). Addition of rice or broken rice to RD linearly increased (P

Objective We aimed to assess whether patients' knowledge about acute myocardial infarction (AMI) has an impact on the prehospital delay-time. Methods This investigation was based on 486 AMI patients who participated in the cross-sectional Munich-Examination-of-Delay-in-Patients-Experiencing-Acute-Myocardial-Infarction (MEDEA) study. A modified German-version of the ACS-Response-Index Questionnaire was used. Multivariate logistic-regression models were used to identify factors associated with knowledge-level as well as the impact of knowledge-level on delay-time. Results High AMI-knowledge shortened median delay-time in men (168[92–509] vs. 276[117–1519] mins, p =0.0069), and in women (189[101–601] vs. 262[107–951]mins, p =0.34). Almost half-of-patients (n=284,58%) demonstrated high AMI-knowledge. High-knowledge were independently associated with male-gender ( OR = 1.47[1.17–1.85]) and General-Practitioner as a knowledge-source ( OR = 1.42[1.14–1.77] ). Old-age ( OR = 0.87[0.86–0.89] ) and previous AMI-history/stent-placement ( OR = 0.65[0.46–0.93] ) were significantly associated with lower-knowledge. Although the majority (476,98%) correctly recognized at least one AMI-symptom, 69(14.2%) patients correctly identified all AMI-symptoms. Additionally, one-in-three believed that heart-attack is always accompanied with severe chest-pain. Elderly-patients and women were more likely to be less-knowledgeable about atypical-symptoms ( p =0.006), present with atypical AMI-presentation ( p p Conclusions Knowledge of AMI-symptoms remains to be substandard, especially knowledge of atypical-symptoms. Knowledge is essential to reduce delay-times, but it is not a panacea, since it is not sufficient alone to optimize prehospital delay-times.

The grain structures and crystallographic textures desired for various applications of aluminium alloys are usually modified by recrystallization during annealing. In this study, the interactions between recrystallization and precipitation were investigated using the same Al-Mn alloy but with different homogenization procedures (which gives different microchemistries in terms of solute level and second phase particle state) and prior cold deformation strains, both of which are easy to realize in industrial practice. The results show that recrystallization and precipitation kinetics are both promoted at large deformations but their mutual interactions also exist. Recrystallization is retarded by precipitation through the suppressing of nucleation and pinning of grain boundary migration, while early finish of recrystallization delays precipitation by reducing their nucleation sites. The delicate interplay between recrystallization and precipitation during annealing leads to different combinations of grain structures and textures. An equiaxed fine grain structure can be obtained when recrystallization is not affected by fine particles while the combined effects of a strong fibrous deformation structure, suppressed nucleation of recrystallization and preferential growth lead to a coarse elongated grain structure. Different crystallographic textures desired for typical applications of Al-Mn alloys can be obtained after annealing simply through the different combinations of homogenization procedures and prior cold deformations.

Rapid heating and cooling thermal cycle of metals in selective laser melting (SLM) generates high tensile residual stress which leads to part distortion. However, how to fast and accurately predict residual stress and the resulted part distortion remains a critical issue. It is not practical to simulate every single laser scan to build up a functional part due to the exceedingly high computational cost. Therefore, scaling up the material deposition rate via increasing heat source dimension and layer thickness would dramatically reduce the computational cost. In this study, a multiscale scalable modeling approach has been developed to enable fast prediction of part distortion and residual stress. Case studies on residual stress and distortion of the L-shaped bar and the bridge structure were presented via the deposition scalability and validation with the experimental data. High residual stress gradient in the building direction was found from high tensile on the surface to high compressive in the core. The part distortion can be predicted with reasonable accuracy when the block thickness is scaled up by 50 times the layer thickness from 30 μm to 1500 μm. The influence of laser scanning strategy on residual stress distribution and distortion magnitude of the bridges has shown that orthogonal scanning pattern between two neighboring block layers is beneficial for reducing part distortion.

Background: Anxiety has been identified as a cardiac risk factor. However, less is known about the impact of generalized anxiety disorder (GAD) on prehospital delay during an acute myocardial infarction (AMI). This study assessed the impact of GAD on prehospital delay and delay related cognition and behavior. Methods: Data were from the cross-sectional Munich examination of delay in patients experiencing acute myocardial infarction (MEDEA) study with a total of 619 ST-elevated myocardial infarction (STEMI) patients. Data on socio-demographic, clinical and psycho-behavioral characteristics were collected at bedside. The outcome was assessed with the Generalized Anxiety Disorder scale (GAD-7). A GAD-7 score greater than or equal to 10 indicates general anxiety disorder. Results: A total of 11.47% (n = 71) MI patients suffered from GAD. GAD was associated with decreased odds of delay compared to patients without GAD (OR 0.58, 95% CI 0.35–0.96), which was more significant in women (112 vs. 238 min, p = 0.02) than in men (150 vs. 198 min, p = 0.38). GAD was highly correlated with acute anxiety (p = 0.004) and fear of death (p = 0.005). Nevertheless, the effect remained significant after controlling for these two covariates. GAD patients were more likely to perceive a higher cardiovascular risk (OR 2.56, 95% CI 1.37–4.76) in 6 months before MI, which leads to the higher likelihood of making self-decision to go to the hospital (OR 2.68, 95% CI 1.48–4.85) in the acute phase. However, GAD was also highly associated with impaired psychological well-being, stress and fatigue (p < 0.0001). Conclusions: In AMI patients, GAD was independently associated with less prehospital delay, but led to an impaired psychological state.

A novel approach to quench detection for high temperature superconducting (HTS) coils is proposed, which is mainly based on phase angle between voltage and current of two coils to detect the quench resistance voltage. The approach is analyzed theoretically, verified experimentally and analytically by MATLAB Simulink and LabVIEW. An analog quench circuit is built on Simulink and a quench alarm system program is written in LabVIEW. Experiment of quench detection is further conducted. The sinusoidal AC currents ranging from 19.9 A to 96 A are transported to the HTS coils, whose critical current is 90 A at 77 K. The results of analog simulation and experiment are analyzed and they show good consistency. It is shown that with the increase of current, the phase undergoes apparent growth, and it is up to 60° and 15° when the current reaches critical value experimentally and analytically, respectively. It is concluded that the approach proposed in this paper can meet the need of precision and quench resistance voltage can be detected in time.

Laser deposited Co-285+WC coating was heat treated at 500 °C (stress relief annealing) for 60 min and cooled to room temperature in a furnace. Optical, scanning microscopy and X-ray diffractometer were used to investigate the microstructure and phases in the coating. An X-ray stress analyzer was used to study the effect of heat treatment on the residual stress in the coating. A microhardness tester and wear tester were used to test the microhardness distribution and friction and wear behavior. A lot of precipitates formed in the annealed Co-285+WC coating. Residual stress and FWHM (full width at half-maximum) of the coating were decreased by annealing. Residual stress values and microhardness decreased by 22–88% and 39%, respectively. Friction coefficient seldom changed by annealing, but circulation of oxide films was brought forward. Relative wear resistance of the annealed Co-285+WC coating was 6.8 times that of the as-deposited coating. Mechanism of the effect of annealing on microstructure, FWHM, residual stress and wear properties were discussed.

Background and aims: Depressed mood and exhaustion (DEEX) have gained attention as a risk predictor for cardiovascular disease (CVD). Studies to estimate its ranking in prediction models are sparse. Methods: The study included 3428 men aged 45-74 years who participated in one of three population-based MONICA/KORA Augsburg surveys conducted between 1984 and 1995. Within a follow-up time of 10 years (31,791 person-years), 557 cases of all-cause mortality and 269 fatal CVD events were observed. Adjusted Cox proportional hazards models were used to assess mortality risks for DEEX and five classical cardiovascular risk factors. The predictive ability was evaluated by the area under the receiver-operating characteristic curve, the integrated discrimination improvement statistics and the net classification improvement. Results: The (crude) absolute mortality risk for DEEX was 23.1 cases per 1000 person-years for all-cause and 11.2 for CVD mortality. The adjusted hazard ratios of 1.52 for all-cause and 1.52 for CVD mortality (p < 0.01) were higher than those for hypercholesterolemia and obesity, but lower than for hypertension, smoking and diabetes. The improvements in risk prediction from DEEX were comparable to those of hypercholesterolemia and obesity, but substantially lower than those of hypertension, smoking and diabetes. The adjusted population-attributable risk (PAR) for DEEX accounted for about 15% for all-cause and CVD mortality, which gives DEEX a middle ranking amongst the classical risk factors. Conclusions: DEEX is a strong predictor of mortality risk, ranking in a medium position amongst classical somatic risk factors.

Objective During an acute myocardial infarction, patients often use denial as a coping mechanism which may provide positive mood regulating effects but may also prolong prehospital delay time (PHD). However, empirical evidences are still sparse. Methods This cross-sectional study included 533 ST-elevated myocardial infarction (STEMI) patients from the Munich Examination of Delay in Patients Experiencing Acute Myocardial Infarction (MEDEA) study. Data on sociodemographic, clinical and psycho-behavioral characteristics were collected at bedside. The outcome was assessed using the Cardiac Denial of Impact Scale (CDIS) with the median split as cutoff point. A total of 206 (41.8%) STEMI patients were thus classified as deniers. Results Deniers were less likely to suffer from major depression (p=0.04), anxiety (p=0.01) and suboptimal well-being (p=0.01) compared to non-deniers during the last six months prior to STEMI. During STEMI, they were less likely to perceive severe pain strength (p=0.04) and racing heart (p=0.02). Male deniers were also less likely to perceive shortness of breath (p=0.03) and vomiting (p=0.01). Denial was not associated with overall delay time. However, in the time window of 3 to 24h, denial accounted for roughly 40min extra delay (356 vs. 316.5min p=0.02 n=196). Conclusions Denial not only contributes to less suffering from acute heart related symptoms and negative affectivity but also leads to a clinically significant delay in the prevalent group.

This paper investigates the mechanism of cleavage fracture in precracked specimen made of Q-T C–Mn steel at the lower shelf of ductile-to-brittle transition curves. The results reveal that the lower shelf region can be divided into three domains: (1) at the lower temperature end (−150 to −130 °C), cleavage is controlled by crack nucleation in the microscopic scale and is driven by increasing applied load which blunts the precrack tip in the macroscopic scale; (2) at moderate low temperatures (−130 to −90 °C) cleavage fracture is controlled by propagation of a second phase particle-crack into contiguous grains in the microscopic scale and is also driven by increasing applied load which further blunts the precrack tip in the macroscopic scale; (3) at the upper temperature end (−90 to −60 °C) the cleavage fracture is controlled by the propagation of the carbide crack into contiguous grains in the microscopic scale, yet in addition to the crack tip blunting for compensating the drop of the yield stress a short fibrous crack is needed to extend from the precrack tip to increase the peak normal stress and to move it closer to the precrack tip. The results also reveal that work hardening plays a key role in triggering cleavage fracture in this temperature region. The normal stress induced by dislocation pile-up impingement, which greatly enhances the applied normal stress, is the essential part of the cracking mechanism and is enhanced by increasing the applied load through strain-hardening effects.

Changes in various grain interfaces, including the grain boundary and phase boundary, are a strong indication of microstructural changes, particularly ultra-fined grains achieved by large strain deformation and subsequent annealing. After direct rolling and cross rolling with the same strain of ε = 2, the distributions of the interfaces in annealed UNS S32304 duplex stainless steel were investigated using electron backscatter diffraction (EBSD) in this study. The ferrite experienced continued recovery, and a high density of low-angle grain boundaries (LAGBs) was produced. The percentage and number of twin boundaries (TBs) and LAGBs varied within the austenite. TBs were frequently found within austenite, showing a deviation from the Kurdjumov-Sachs (K-S) orientation relationship (OR) with ferrite matrix. However, LAGBs usually occur in austenite, with the K-S OR in the ferrite matrix. LAGBs were prevalent in the precipitated austenite grains, and therefore a strong texture was introduced in the cross-rolled and annealed samples, in which the precipitated austenite readily maintained the K-S OR in the ferrite matrix. By contrast, more TBs and a less robust texture were found in the precipitated austenite in direct-rolled and annealed samples, deviating from the K-S OR.

The surface of dielectric barium strontium titanate (BST) film was modified by a self-assembled monolayer (SAM) of mono-dodecyl phosphate (DDPO4) from aqueous solutions of alkyl phosphate ammonium salts. The phosphate terminal groups were believed to anchor to the Ti atoms through oxygen bridges with the terminal methyl groups exposed outwardly, resulting in a highly hydrophobic surface with an advancing water contact angle (CA) of 99.8°, compared with the original CA 40.8° of the bare BST surface. X-ray photoelectron spectroscopy (XPS) showed the dense coverage of the SAM and immobilized BSA layer. The microscopic features and the biosensing properties were characterized by atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) in the presence of [Fe(CN)6]3−/4− as a redox couple. AFM images revealed that bovine serum albumin (BSA) was well-immobilized on the DDPO4-modified BST surface. The EIS showed a significant increase in the electron-transfer resistance. Specific binding of anti-BSA on the immobilized BSA surface was evidenced by AFM imaging and EIS. It was demonstrated that the specific binding of anti-BSA can be quantitatively detected by measuring the electron-transfer resistance. The investigation indicated the potential application of the dielectric film for electrochemical biosensors.

The truncated eigenvalue equations of lattice gauge theory are studied using truncation scheme that preserves the continuum limit. The order mixing problem due to the unimodular condition of group is studied. The third-order and the fourth-order results for long wavelength wavefunction and the mass gap of -dimensional theory are presented using various prescriptions for the definition of the order of a graph.