Multi-CMP system with data communication on the fly

The paper concerns new communication solutions for hierarchical Chip Multiprocessor (CMP) systems composed of many CMP modules interconnected by a global data exchange network. New architectural solutions for internal module data communication are presented in the presence of hierarchical data caches in CMP modules. Inside CMP modules, dynamic shared memory core clusters are organized around L1–L2 data cache busses. Such clusters enable a group-oriented data communication based on reads on the fly to L1 banks of data present on the busses by many cores at a time. Dynamic switching of cores between such L1–L2 busses is done with porting data in core’s L1 caches. Together with data reads on the fly, it provides a very efficient intercluster “communication on the fly,” especially useful for transfers of strongly shared data. It provides fast cache to cache group data transmissions and eliminates standard transactions based on shared memory in the system. Comparative experimental results based on automatic scheduling of program data flow graphs and execution in a simulator of the proposed architecture evaluate the assumed architectural solutions. The multi-CMP system structure is assessed while taking into account technological limitations of the size of the single CMP module.     

Relating Task Demand,Mental Effort and Task Difficulty with Physicians’ Performance during Interactions with Electronic Health Records (EHRs)

Objective was to assess the relationship between task demand, mental effort, task difficulty, and performance during physicians’ interaction with electronic health records (EHRs). Seventeen physicians performed three EHR-based scenarios with varying task demands. Mental effort was measured using eye tracking measures via task evoked pupillary responses (TEPR), blink frequency, and gaze speed; task difficulty (or user behavior) was measured using frequent mouse click patterns and task flow; user performance was quantified using two types of omission errors: (i) omission errors with no evidence of trying to complete the task and (ii) omission error with evidence of trying but unable to complete the task. The results indicated that task demand significantly increased mental effort, but not task difficulty. Task demand, mental effort, and task difficulty all predicted performance. Specifically, there was a significant relationship between (i) task demand, TEPR and omission errors with no evidence of trying to complete the task, and (ii) blink frequency, repeated search clicks and omission error with evidence of trying but unable to complete the task. In concert, results suggest that physicians’ performance during EHR interaction was negatively affected by task demands and increase in mental effort. This highlight the need for implementation of appropriate quality assurance (QA) measures, in addition to EHR usability improvement, to minimize omission errors and improve physician’s performance. Additionally, the lack of relationship between task demand and task difficulty highlights a need for further methodological and empirical studies to advance our understanding from theory to application during physician–EHR interaction.     

Ontology engineering step in design science research methodology: a technique to gather and reuse knowledge

Design science (DS) is an emerging research paradigm in the information systems field. One of its challenges is to systematically structure knowledge for business solution artefacts. In this paper, we address this challenge by presenting an ontology engineering process. It structures gathered knowledge based on domain-specific concepts and relations. Application of the process results in an improvement in DS artefacts in terms of representational information quality. The goal of the paper is to place the ontology engineering process in the DS research methodology and provide pragmatic steps to follow the process.     

Anisotropy of Mechanical Properties in a Hot‐Pressed Boron Carbide

Effects of microstructure and material properties on the mechanical behavior of hot‐pressed boron carbide are presented. The microstructure and intrinsic microstructural inhomogeneities have been characterized using scanning electron microscopy characterization techniques (SEM/EDS/EBSD). In situ mechanical characterizations of the boron carbide microstructure and its larger inhomogeneities have been performed by nanoindentation. Macroscopic dynamic and quasi‐static compressive responses have been studied in two characteristic orientations (parallel and perpendicular to the hot‐pressing direction) using a modified compression Kolsky bar setup (strain rates of /s) and standard MTS test machine (strain rates of /s). The microstructure characterization showed that boron carbide has a fine‐grained microstructure with a complex superposition of nonmetallic inclusions, such as free carbon, AlN, and BN. Nanoindentation tests conducted in three principal planes of the plate revealed an anisotropy of the mechanical properties. The compression tests revealed that the strength of this hot‐pressed boron carbide is orientation dependent. Detailed SEM analysis indicated transgranular fracture and microcracking originating at large carbon inclusions. Influences of microstructural anisotropy on the mechanical response of the material are discussed.     

Influence of selected WMA additives on viscoelastic behaviour of asphalt mixes and pavements

Warm mix asphalt additives are effective in decreasing production, laying and compaction temperatures of asphalt mixes. However, there are still questions concerning influence of warm mix additives on properties of asphalt mixes and pavement performance. This paper presents results of the comprehensive research of viscoelastic behaviour of asphalt mixes and pavement structures with layers made with warm mix asphalt additives at high temperatures. Two additives of significantly different effects on mixes at higher temperatures were selected for analysis, namely aliphatic synthetic wax produced with the use of Fisher–Tropsch method and formulation of surfactant- based molecules (ionic and non-ionic). Viscoelastic properties of mixes with these two additives and, as a reference mix, with neat unmodified asphalt binder were determined in uniaxial compression with sinusoidal loading using Asphalt Mixture Performance Test. The viscoelastic analysis of pavement structures was performed with use of the VEROAD software and data from laboratory testing. Two different pavement structures were analysed, for light and heavy traffic. The temperature distribution in pavement structure during the hottest summer day in northern Poland in 2012 was taken into account. The model of pavement was loaded with moving wheel at different speeds. The analysis has shown that two tested warm mix additives had different effect on viscoelastic transient response at high temperatures. One of them (Fischer–Tropsch wax) evidently caused an increase in resistance of asphalt mix and pavement structure to loading at high temperature. The second additive (formulation of surfactant-based molecules) slightly reduced resistance of asphalt mix and pavement to loading at high temperatures as compared with the reference mix.     

Screening of Self-Assembling of Collagen IV Fragments into Stable Structures Potentially Useful in Regenerative Medicine

The aim of the research was to check whether it is possible to use fragments of type IV collagen to obtain, as a result of self-assembling, stable spatial structures that could be used to prepare new materials useful in regenerative medicine. Collagen IV fragments were obtained by using DMT/NMM/TosO⁻ as a coupling reagent. The ability to self-organize and form stable spatial structures was tested by the CD method and microscopic techniques. Biological studies covered: resazurin assay (cytotoxicity assessment) on BJ, BJ-5TA and C2C12 cell lines; an alkaline version of the comet assay (genotoxicity), Biolegend Legendplex human inflammation panel 1 assay (SC cell lines, assessment of the inflammation activity) and MTT test to determine the cytotoxicity of the porous materials based on collagen IV fragments. It was found that out of the pool of 37 fragments (peptides 1–33 and 2.1–2.4) reconstructing the outer sphere of collagen IV, nine fragments (peptides: 2, 4, 5, 6, 14, 15, 25, 26 and 30), as a result of self-assembling, form structures mimicking the structure of the triple helix of native collagens. The stability of spatial structures formed as a result of self-organization at temperatures of 4 °C, 20 °C, and 40 °C was found. The application of the MST method allowed us to determine the K_d of binding of selected fragments of collagen IV to ITGα1β1. The stability of the spatial structures of selected peptides made it possible to obtain porous materials based on their equimolar mixture. The formation of the porous materials was found for cross-linked structures and the material stabilized only by weak interactions. All tested peptides are non-cytotoxic against all tested cell lines. Selected peptides also showed no genotoxicity and no induction of immune system responses. Research on the use of porous materials based on fragments of type IV collagen, able to form stable spatial structures as scaffolds useful in regenerative medicine, will be continued.     

Thymosin β4 Is an Endogenous Iron Chelator and Molecular Switcher of Ferroptosis

Thymosin β4 (Tβ4) was extracted forty years agofrom calf thymus. Since then, it has been identified as a G-actin binding protein involved in blood clotting, tissue regeneration, angiogenesis, and anti-inflammatory processes. Tβ4 has also been implicated in tumor metastasis and neurodegeneration. However, the precise roles and mechanism(s) of action of Tβ4 in these processes remain largely unknown, with the binding of the G-actin protein being insufficient to explain these multi-actions. Here we identify for the first time the important role of Tβ4 mechanism in ferroptosis, an iron-dependent form of cell death, which leads to neurodegeneration and somehow protects cancer cells against cell death. Specifically, we demonstrate four iron²⁺ and iron³⁺ binding regions along the peptide and show that the presence of Tβ4 in cell growing medium inhibits erastin and glutamate-induced ferroptosis in the macrophage cell line. Moreover, Tβ4 increases the expression of oxidative stress-related genes, namely BAX, hem oxygenase-1, heat shock protein 70 and thioredoxin reductase 1, which are downregulated during ferroptosis. We state the hypothesis that Tβ4 is an endogenous iron chelator and take part in iron homeostasis in the ferroptosis process. We discuss the literature data of parallel involvement of Tβ4 and ferroptosis in different human pathologies, mainly cancer and neurodegeneration. Our findings confronted with literature data show that controlled Tβ4 release could command on/off switching of ferroptosis and may provide novel therapeutic opportunities in cancer and tissue degeneration pathologies.     

基于虚拟变形法的移动质量识别方法研究

在车-桥耦合系统的移动质量(荷载)识别反问题中,识别移动质量会面临重构系统、优化缓慢的问题;而若直接识别移动荷载常常会遇到病态问题且对噪音敏感。针对这些缺陷,根据虚拟变形法(VDM)的结构快速重分析思想,提出移动动态影响矩阵,实现利用较少的传感器即可快速而准确地识别移动质量(荷载)。以移动质量为优化变量,避免了识别荷载常遇到的病态问题,对噪音鲁棒性强;且需要传感器信息少。每步优化中,利用移动动态影响矩阵,无需时时重构车-桥耦合系统的时变系统参数矩阵,优化效率高。VDM方法的思想是将实际结构的响应计算转化为初始结构模型在相同外荷载作用下的响应,与在结构模型发生改变的位置施加相关的虚拟变形或虚拟力引起的响应的线性叠加。通过简支梁模型和框架梁模型验证了该方法的可行性和有效性,即使在5%的噪声影响下,利用一个传感器就可以很好地识别多个移动质量。     

Life cycle assessment of opencast lignite mining

The life cycle phase of fossil fuel extraction is mainly considered in the life cycle assessment (LCA) when evaluating the energy production processes.It is the...