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Alkali-activated slag recycled coarse aggregate concrete (AAS-RAC) is a novel type of green building material with significant growth potential, utilizing waste slag and construction waste effectively. However, its large shrinkage and poor toughness limit its further utilization. Adding fiber is the crucial way to limit its shrinkage. Therefore, the effects of fiber type and content on the shrinkage performance of AAS-RAC were systematically studied. The results show that the incorporation of recycled aggregate increases the shrinkage of AAS-RAC, and AAS-RAC of full recycled aggregate is 59% higher than that of undoped aggregate. The addition of steel fiber, polypropylene fiber and basalt fiber can effectively reduce the shrinkage of AAS-RAC. Among them, steel fiber has the best inhibition effect, and 0.6% steel fiber can reduce the shrinkage of AAS-RAC by 30.6%. The AAS-RAC shrinkage model considering the influence of fiber content and recycled aggregate is established. The research results provide an effective way to reduce the shrinkage of AAS-RAC. [ABSTRACT FROM AUTHOR]

The dowel-bearing properties of a newly laminated flattened-bamboo (LFB) composite for engineering use was studied in this research by using the 5% bolt diameter offset method. The effects of specimen dimensions, bolt diameter, density, and bolt placed direction were included. Computed tomography (CT) and scanning electron microscope (SEM) were used to identify the failure type. The test results indicate that the parallel-to-grain dowel-bearing strength of LFB generally increased with an increasing density. When the bolt was placed along the LFB's radial direction, the parallel-to-grain dowel-bearing strength approximately remained a constant (52 MPa) with the change of specimen dimensions and bolt diameter, while when the bolt was along the tangential direction, the dowel-bearing strength increased with the raising ratio of specimen thickness and bolt diameter. The first failure type was a crushing failure of bamboo fiber underneath the bolt, it happened when bolt diameter was small (12 mm and 14 mm) and placed along LFB's radial direction. The second type was a splitting failure due to the lateral force generated by the bolt embedded into specimen, bamboo fiber splitting failure dominated for specimens with bolt along radial direction, while when bolt along tangential direction, glue layer splitting happened. The measured dowel-bearing strength was compared to the predictions obtained from equations in current wood specifications and articles. The results indicated that, except for the predicted values from the NDS equation (max error = 36%), which showed relatively reasonable agreement with the test values, the remaining predicted values exhibited discrepancies with the test values. To obtain proper predicted values, equations include density and ratio of specimen thickness and bolt diameter were proposed for calculation of LFB's parallel-to-grain dowel-bearing strength. [ABSTRACT FROM AUTHOR]

This article reports a comparative analysis between glass waste and fly ash (which is the most studied waste for the alkali-activated products) to measure their effectiveness as a sole precursor to produce geopolymers. Globally, around 11.4 million tonnes of glass waste is generated per annum, and this needs to be managed properly. To address this issue, in this study, glass waste which was mostly manufactured bottles and containers was used in pulverized form. The molarity of the sodium hydroxide (NaOH) solution was kept as 6 M, 8 M, and 10 M. The sodium silicate-to-sodium hydroxide (Na2SiO3/NaOH) solution mix ratio was varied between 1.5 and 3.5. Mechanical (compressive and flexural strength) and durability (resistance to different levels of sulfuric acid) aspects were studied along with micro-analysis (structural, elemental, and thermal). Controlled ambient temperature curing was followed for all the samples. Our findings showed that mechanical properties were dependent on the molarity, silicate modulus, and alkaline mixture (AM) ratio. The glass waste showed substantial amount of long-term strength development over fly ash with a maximum compressive strength gain at 28 d and 90 d curing age of 90% and 194% for 8M1.5AM and 6M1.5AM mixture, respectively. For flexural strength, it was 49% and 62% gain at 28-d and 90-d curing, respectively, for 10M1.5AM mixture. The glass waste also offered relatively higher resistance to acid attack with a maximum compressive strength loss of 61% and 55.7%, whereas fly ash-based mixtures recorded 75% and 71.73% reduction for 5% and 3% H2SO4 attack for 28 d, respectively. Field emission scanning electron microscopy (FE-SEM) revealed that the glass waste specimens were more compact than fly ash-based specimens. Thermogravimetric analysis (TGA) results indicate that glass waste-based geopolymers are more thermally resistant than fly ash-based geopolymers when exposed to a systematic increment in temperature. Ultimately, promising results in terms of mechanical and durability aspects propose the use of glass waste as a binder in geopolymeric masonry mortar applications. Glass waste has a full potential to be a sole precursor to produce geopolymer under ambient temperature curing conditions. This will contribute towards sustainable environment by paving path for an effective utilization of the glass waste. [ABSTRACT FROM AUTHOR]

Despite sophisticated technologies for representational fidelity in hybrid meetings, in which co-located and remote participants collaborate via video or audio, meetings are still often disrupted by practical problems with trying to include remote participants. In this paper, we use micro-analysis of three disruptive moments in a hybrid meeting from a global software company to unpack blended technological and conversational practices of inclusion and exclusion. We argue that designing truly valuable experiences for hybrid meetings requires moving from the traditional, essentialist, and perception-obsessed user-centered design approach to a phenomenological approach to the needs of meetings themselves. We employ the metaphor of 'configuring the meeting' to propose that complex ecologies of people, technology, spatial, and institutional organization must be made relevant in the process of design. [ABSTRACT FROM AUTHOR]

The disposal of highly alkaline and hazardous bauxite residue mud generated from the Bayer process in the alumina industry leads to the serious environmental impact on natural resources. Effective and bulk utilization of red mud needs to be done to minimize an adverse impact on environment. The present study contracts to explore the possible utilization of red mud as a geomaterial by modifying its properties with fly ash (Class 'F'). Detailed geotechnical properties (plasticity characteristics, compaction characteristics, swell index and Unconfined compressive strength (UCS)), physicochemical properties (pH and electrical conductivity) and micro-analyses (XRD, SEM, EDAX and FTIR) have been performed in the red mud amended with varying fly ash content up to 80%. The characterization of red mud demonstrates the higher value of specific gravity, liquid limit, optimum water content (OWC), maximum dry density (ρdmax), pH value, and electrical conductivity than that of the same of fly ash. Further, the amendment with various fly ash content has observed a significant effect on the plasticity and compaction characteristics of the red mud. The results show a significant reduction in liquid limit, plastic limit, OWC and ρdmax of red mud with an increase in fly ash content. Ultimate increase in the UCS of red mud is observed at its substitution with 15% fly ash which can be considered as an Optimum Fly Ash Content (OFC) from strength point of view. Further, experimental results are elucidated through physicochemical and microanalyses. [ABSTRACT FROM AUTHOR]

This paper reports on activities carried out as part of a pre-conservation studies of the painting by Dmitry Levitsky, "The Portrait of F.P. Makerovsky in a Masquerade Costume" (1789, the State Tretyakov Gallery). Samples were taken and prepared for further study within the following algorithm. Using optical microscopy of cross-sections of the samples taken, structural elements of layered compositions were revealed and external differences between them were established. X-ray fluorescence spectroscopy was used to evaluate the elemental composition of the painting surface and cross-sections of samples. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy was used to clarify the elemental composition of each of the structural elements of the samples taken, their submicro- and microdimensional inclusions, to map the distribution of chemical elements over the studied surface, and to determine the dispersion of organic and inorganic components contained in the material. Micro-FTIR was used to identify functional groups and to determine the main classes of inorganic compounds, as well as binders, used, including in the local analysis of micro-inclusions. The list of specific chemical compounds in the composition of the studied paint layers and grounds, which included an examination of the varnish coating, was determined with micro-Raman spectroscopy using data obtained by the above methods. As a result of the study, complementary information was obtained on the chemical composition of the inorganic components used, of the binder and of the varnish coating, which is required for further conservation of this work of art. [ABSTRACT FROM AUTHOR]

The 50A and 70A asphalts produced by the same oil source have great differences in macroscopic properties. However, Fourier transform infrared spectra of 50A and 70A asphalts are almost identical with no differentiation in fingerprint region which offers great difficulty in bifurcation in chemical compositions of the two types of asphalts. To cope with these deficiencies, this study is aimed to investigate the composition and micro-performance of 50A and 70A asphalts via other unequivocal techniques including elemental analysis, scanning electron microscopy, fluorescence microscopy, X-ray diffraction analysis, gel permeation chromatography and nuclear magnetic resonance spectroscopy. Through these analyses, it was found that high temperature sensitive property, i.e., low penetration index of 50A asphalt was due to its higher contents of alkane moieties. Similarly, the dynamic viscosity of 50A asphalt was much higher than that of 70A asphalt due to larger relative molecular weight, high aromatic carbon contents and more aromatic rings in the former. This study systematically explained the reasons responsible for the differences in the macroscopic phenomena of different types of asphalts produced from the same oil source, which can establish a bridge between the macro-test results and microscopic properties of asphalt and hence can best analyze asphalt produced from the same oil source resulting in collection of broader and diverse information. [ABSTRACT FROM AUTHOR]

Children with social communication disorders are known to experience more problematic peer relations than typically-developing children. However, detailed observation of their behaviour and communication during interaction with peers has not previously been undertaken. Micro-analytic observational methods were used to analyse the audio-taped interaction of children ( N = 112) selected from mainstream schools (ages 5-6 years-old) on a computerised dyadic collaborative task. Comparisons were made between children with average-to-high- and low-pragmatic language skill as measured by the Test of Pragmatic Skills. Dyads were composed of an average-to-high-skilled child plus a low-skilled child (32 dyads), or of two average-to-high-skilled children (24 dyads). Consistently with their pragmatic language scores, low-skilled children were more likely to ignore other children's questions and requests than were average-to-high-skilled children. When average-to-high-skilled children worked with low-skilled children, as opposed to with other average-to-high-skilled children, they showed some sensitivity and adaptation to these children's difficulties; they used significantly more directives, clarification and provided more information. However, there was a cost in terms of the emotional tone of these interactions; when working with low-skilled children, the average-to-high-skilled children expressed considerably more negative feelings towards their partners than with another average-to-high-skilled child. In conclusion, observation of the interaction of average-to-high- and low-skilled children suggests promise for peer-assisted interventions and specifies which communicative behaviours could be targeted. However, care should be taken to manage the affective climate of these interactions for the benefit of all children involved. [ABSTRACT FROM AUTHOR]

Objectives: This study assesses the accuracy of the immediate blood separation method, a novel blood sampling strategy that enables blood analysis in any possible location. Methods: We conducted a cross-validation study between data from immediate blood separation and conventional methods. During the annual medical examinations in 2006 of a company located in an Osaka suburb, blood was drawn from workers ( n = 256; males 200, females 56) by puncturing their middle finger as well as venipuncture of the antecubital vein, by medical personnel. The following nine parameters were evaluated by autoanalyzer: aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transpeptidase (γGT), triglyceride, total cholesterol, high-density lipoprotein (HDL) cholesterol, urea nitrogen, uric acid, and creatinine. Results: After comparing data from the two methods using correlation analysis and regression analysis, we found a close R value (coefficient of determination) relationship that ranged from 0.996 to 1.000 for each item. The R value was 0.998 for Log AST, 0.997 for Log ALT, 0.999 for Log γGT, 1.000 for Log triglyceride, 1.000 for total cholesterol, 0.999 for HDL cholesterol, 0.998 for urea nitrogen, 0.999 for uric acid, and 0.996 for creatinine. Relationship was satisfactory for all nine items tested. Conclusion: Our results prove the reliability of data from the immediate blood separation method in an occupational health setting. The method enables self-testing by medically unskilled people, which is an important process to prevent lifestyle-related diseases. [ABSTRACT FROM AUTHOR]

This work is focused on the development of miniaturized instrumentation formats for integrated biochemical and biological sample preparation. In particular, the paper is focused on microfluidic systems for the purification of cells, uncoated nano particles, and surface coated nano particles. Microfluidic systems will be described for purifying cells from whole blood, sorting of blood cells based on their electrophysiological characteristics, and separating and purifying the components of a blood cell homogenate. Additionally, the microscale sample preparation systems will be shown to be effective in purifying complex samples of nano particles based on the particles physical size and effective electrical charge. The microsystems will be demonstrated for the purification of samples containing polystyrene nano particles with multiple diameters as well as for samples containing a mixture of uncoated and surface coated nano particles. The formats discussed in this work include the micro-electrophysiological characterization (μ-EPC) system; the micro-thermal field flow fractionation (μ-TFFF) system; and the micro-electrical field flow fractionation (μ-EFFF) system. The microscale cellular electrophysiological characterization system is used for cell sorting and selection. The cell sorting and selection is accomplished using impedance spectroscopy on single cells. The system has been shown to be effective in sorting blood cells by cell type (i.e., red, white) and by sub populations (e.g., viable leukocytes, non viable leukocytes). The μ-TFFF system is a chromatographic separation technique for fractionating particle samples based on the heat capacity, thermal conductivity and physical size of the particles. The μ-EFFF system fractionates particle samples based on the physical size and zeta potential (effective electrical charge) of the particles within the sample. The electrical and thermal FFF systems are capable of separating particle samples with constituents in the diameter range from approximately 1 nm to 1 μm. The separation and purification of a variety of nano particles will be demonstrated in the field flow fractionation systems including cells, cellular sub-components, uncoated polystyrene nano particles, and protein coated (Protein A) polystyrene nano particles. [ABSTRACT FROM AUTHOR]

Preneoplastic liver lesions were produced in female Wistar rats by oral administration of 2-acetyl-aminofluorene for 165 days succeeded by a carcinogen-free standard diet up to 420 days. During the treatment numerous altered hepatic foci (AHF) and hyperplastic nodules (HN) were detected histochemically by a focal decrease or lack of adenosine-5-triphosphatase and glucose-6-phosphatase (G-6-Pase) activities. In addition, the immunohistochemically demosntrable amount of L-type pyruvate kinase was clearly reduced. The histochemically demonstrated decrease of G-6-Pase was substantiated by microbiochemical determination of the enzyme activity in microdissected material. Moreover, during the experimental period a continuous decrease in glucokinase and an increase in hexokinase was detected microbiochemically within AHF and HN. These alterations indicate, a shift in the carbohydrate metabolism from gluconeogenesis to glucose utilization and pentose-phosphate-pathway for biosynthesis of nucleic acids. Beside other oncofetal markers, HK may be used as indicator of the early stages of liver carcinogenesis. [ABSTRACT FROM AUTHOR]

The ability to characterize individual microscopic particles is important in many areas of science and technology. A variety of microbeam analysis methods are capable of providing information on microscopic particles. With electron probe X-ray microanalysis quantitative analysis is possible under well controlled conditions. Using computer controlled electron microscopes it is feasible to characterize a large number of individual particles. The application of this technique requires the use of multivariate data analysis procedures for the interpretation of the large amount of data obtained. [ABSTRACT FROM AUTHOR]

The application of image processing in secondary ion mass spectrometry is discussed. The Cameca 4f SIMS uses a single microchannel plate and a highly sensitive camera in combination with an image processor with real time capabilities (Kontron IBAS). An automation procedure with image integration, extended dynamic range image acquisition and retro depth profiling is presented and illustrated with practical applications. [ABSTRACT FROM AUTHOR]

Spark source mass spectrometry in combination with principal component analysis and clustering analysis was used to investigate the trace element distributions in metallic samples. The analysis of Zn and Cu samples and a comparison with direct imaging secondary ion microscopy demonstrated the consistency of the approach. [ABSTRACT FROM AUTHOR]