A systematic mapping study on the combination of static and dynamic quality assurance techniques

Context

A lot of different quality assurance techniques exist to ensure high quality products. However, most often they are applied in isolation. A systematic combination of different static and dynamic quality assurance techniques promises to exploit synergy effects, such as higher defect detection rates or reduced quality assurance costs. However, a systematic overview of such combinations and reported evidence about achieving synergy effects with such kinds of combinations is missing.

Objective

The main goal of this article is the classification and thematic analysis of existing approaches that combine different static and dynamic quality assurance technique, including reported effects, characteristics, and constraints. The result is an overview of existing approaches and a suitable basis for identifying future research directions.

Method

A systematic mapping study was performed by two researchers, focusing on four databases with an initial result set of 2498 articles, covering articles published between 1985 and 2010.

Results

In total, 51 articles were selected and classified according to multiple criteria. The two main dimensions of a combination are integration (i.e., the output of one quality assurance technique is used for the second one) and compilation (i.e., different quality assurance techniques are applied to ensure a common goal, but in isolation). The combination of static and dynamic analyses is one of the most common approaches and usually conducted in an integrated manner. With respect to the combination of inspection and testing techniques, this is done more often in a compiled way than in an integrated way.

Conclusion

The results show an increased interest in this topic in recent years, especially with respect to the integration of static and dynamic analyses. Inspection and testing techniques are currently mostly performed in an isolated manner. The integration of inspection and testing techniques is a promising research direction for the exploitation of additional synergy effects.     

Experimental and theoretical studies of the influence of surface conditions on radiative properties of opaque materials

Radiative properties of opaque materials strongly depend on their surface condition. The fabrication of superficial cavities of various forms and dimensions modifies the directional spectral emissivities or absorptivities. They are usually increased compared to those of optically smooth material; the gain depends on the material, the type of cavities, as well as the wavelength and the direction of the emitted or incident radiation. When grooves of dimensions larger than are fabricated in a sample, the models, taking into account the successive reflections on their inner sides, give a good agreement with experimental data. But a similar theory does not explain the substantial increase of the infrared emissivity of ballblasted samples.     

Loss of Nckx3 Exacerbates Experimental DSS-Induced Colitis in Mice through p53/NF-κB Pathway

Inflammatory bowel diseases (IBDs) comprises a range of chronic inflammatory conditions of the intestinal tract. The incidence and prevalence of IBDs are increasing worldwide, but the precise etiology of these diseases is not completely understood. Calcium signaling plays a regulatory role in cellular proliferation. Nckx3, a potassium-dependent Na⁺/Ca²⁺ exchanger, is not only expressed in the brain but also in the aortic, uterine, and intestinal tissues, which contain abundant smooth muscle cells. This study investigated the role of Nckx3 in intestinal inflammation. Microarray analyses revealed the upregulation of the innate immune response-associated genes in the duodenum of Nckx3 knockout (KO) mice. The Nckx3 KO mice also showed an increase in IBD- and tumorigenesis-related genes. Using dextran sodium sulfate (DSS)-induced experimental colitis mice models, the Nckx3 KO mice showed severe colitis. Furthermore, the pathways involving p53 and NF-κB signaling were significantly upregulated by the absence of Nckx3. Overall, Nckx3 plays a critical role in the innate immune and immune response and may be central to the pathogenesis of IBD.     

Efficient Large-Scale Filter/Filterbank Design via LMI Characterization of Trigonometric Curves

Many filter and filterbank design problems can be posed as the optimization of linear or convex quadratic objectives over trigonometric semi-infinite constraints. Recent advances in design methodology are based on various linear matrix inequality (LMI) characterizations of the semi-infinite constraints, and semidefinite programming (SDP) solutions. Despite these advances, the design of filters of several hundredth order, which typically arise in multicarrier communication and signal compression, cannot be accommodated. This hurdle is due mainly to the large number of additional variables incurred in the LMI characterizations. This paper proposes a novel LMI characterization of the semi-infinite constraints that involves additional variables of miminal dimensions. Consequently, the design of high-order filters required in practical applications can be achieved. Examples of designs of up to 1200-tap filters are presented to verify the viability of the proposed approach.     

Comparison of test protocols for the standard room/corner test

As part of international efforts to evaluate alternative reaction‐to‐fire tests, several series of room/corner tests have been conducted. Materials tested were mostly different wood products but included gypsum board and a few foam plastics. This is a review of the overall results of related studies in which the different test protocols for the standard room/corner test were used. Differences in the test protocols involved two options for the ignition burner scenario and whether or not the ceiling was also lined with the test materials. The test materials were placed on three walls of the room in all the tests. The two burner scenarios were (1) 40 kW for 300 s followed by 160 kW for 300 s and (2) 100 kW for 600 s and 300 kW for 600 s. The 40 and 160 kW burner scenario without the ceiling lined did not provide a severe enough test for flashover to occur with fire‐retardant‐treated materials. Use of the 100 and 300 kW burner scenario without lining the ceiling provided the ability to differentiate between wood products with ASTM E 84 flame spread indexes of 70 to 125 and those with higher flame spread indexes. Lining the ceiling with test material creates a more severe test.     

Air-Liquid-Interface Differentiated Human Nose Epithelium: A Robust Primary Tissue Culture Model of SARS-CoV-2 Infection

The global urgency to uncover medical countermeasures to combat the COVID-19 pandemic caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has revealed an unmet need for robust tissue culture models that faithfully recapitulate key features of human tissues and disease. Infection of the nose is considered the dominant initial site for SARS-CoV-2 infection and models that replicate this entry portal offer the greatest potential for examining and demonstrating the effectiveness of countermeasures designed to prevent or manage this highly communicable disease. Here, we test an air–liquid-interface (ALI) differentiated human nasal epithelium (HNE) culture system as a model of authentic SARS-CoV-2 infection. Progenitor cells (basal cells) were isolated from nasal turbinate brushings, expanded under conditionally reprogrammed cell (CRC) culture conditions and differentiated at ALI. Differentiated cells were inoculated with different SARS-CoV-2 clinical isolates. Infectious virus release into apical washes was determined by TCID₅₀, while infected cells were visualized by immunofluorescence and confocal microscopy. We demonstrate robust, reproducible SARS-CoV-2 infection of ALI-HNE established from different donors. Viral entry and release occurred from the apical surface, and infection was primarily observed in ciliated cells. In contrast to the ancestral clinical isolate, the Delta variant caused considerable cell damage. Successful establishment of ALI-HNE is donor dependent. ALI-HNE recapitulate key features of human SARS-CoV-2 infection of the nose and can serve as a pre-clinical model without the need for invasive collection of human respiratory tissue samples.     

3-Alkylated (R)-2,3-Dihydroxyalkyl p-Toluenesulfonates – homochiral building blocks for modified steroid side chains

Oxidative cleavage of 1,2:5,6-di-0-cyclohexylidene-D-mannitol ( 2 ) with lead (IV) acetate yields (R)-2,3-0-cyclohexylideneglyceraldehyde, which was transformed by oxidation and esterification into methyl 2,3-0-cyclohexylideneglycerate. Grignard reaction with various alkylmagnesium halides followed by acid-catalyzed removal of the acetal group and reaction with p-toluenesulfonyl chloride in pyridine furnished the title compounds ( 8a – d ) in good chemical overall yield and high enantiomeric purity. The compounds were prepared as intermediates for the synthesis of a series of steroids with a modified side chain.     

Heat resistance in Escherichia coli and its implications on ground beef cooking recommendations in Canada

This study assessed the adequacy of the current cooking recommendations in relation to heat resistant Escherichia coli by evaluating eight potentially heat resistant E. coli strains (four generic and four E. coli O157:H7) along with AW1.7. The D_60°C-values for these strains varied from 1.3 to 9.0 min, with J3 and AW1.7 being the least and most heat resistant strains, respectively. The D_60°C-values for E. coli 62 and 68 were similar and were not affected by growth medium, while the heat resistance of C37, J3, and AW1.7 varied with the growth medium. When heated in extra lean ground beef (100 g) in vacuum pouches, the mean D_54°C, D_57°C, and D_60°C-values were 44.8, 18.6, and 2.9 min for C37, 13.8, 6.9, and 0.9 min for J3, and 40.5, 9.1, and 6.1 min for AW1.7. Burger temperatures continued to rise after being removed from heat when the target temperature was reached, by 3–5°C, and resting of 1 min would result in a destruction of 133, 374 and 14 log C37, J3 and AW1.7. These findings along with the very low occurrence of heat resistant E. coli expected in ground beef show that cooking ground beef to 71°C should be adequate.     

VHCF properties of nitrided 18Ni maraging steel thin sheets with different Co and Ti content

High cycle fatigue (HCF) and very high cycle fatigue (VHCF) properties of two 18Ni maraging steels with different cobalt and titanium content and similar static strength are investigated. Ultrasonic fatigue tests are performed with thin sheets with nitrided surfaces at load ratio R = 0.1. The specimens are mounted on a carrier and are forced to joint vibrations at approximately 20 kHz. The increase of Co content and the elimination of Ti improved the HCF and VHCF strength of 18Ni maraging steel. TiN inclusions if Ti is present and Al₂O₃ inclusions in the Ti free material with sizes (area_INC)^1/2 smaller than 10 µm were preferential crack initiation locations. Considering inclusions as initial cracks, the minimum stress intensity range for VHCF failure is 1.2 MPam^1/2 for TiN inclusions and 1.8 MPam^1/2 for Al₂O₃ inclusions. Data scatter may be slightly reduced if lifetimes are presented versus stress amplitudes multiplied by (area_INC)^1/12 rather than in an S–N diagram.     

做专市场合作共赢——记 H3C 2007 中国区渠道招募大会

4月6日,H3C在杭州举办了主题为“合作成就未来”的“H3C 2007中国区渠道招募大会”,与全国400家渠道合作伙伴共同分享了H3C 2007中国市场战略。值得关注的是,此次在H3C本部杭州举办的渠道招募大会受邀渠道商锁定在安全、存储以及监控领域有丰富经验和市场优势的专业渠道代理商,明确传递出H3C由单一网络产品向多元产品战略转变的意图,并打造专业渠道,目标直抵专业市场。