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Two endoglucanases were purified to electrophoretic homogeneity from the culture filtrate of a mutant strain Trichoderma sp. M7. EG-III and EG-IV had Mr of 49.7 and 47.5 kDa, and estimated pi values of 3.7 and 6.35, respectively. The optimal pH and temperature values were determined to be pH 5.0 and 60°C for the first cellulase, whereas pH 5.2 and 50 °C were optimal for the other. Endoglucanases exhibited typical Michaelis-Menten kinetics with Km and V values of 2.9 mg ml−1 and 60498.5 μmol min−1 mg−1 for EG-III and 3.8 mg ml−1 and 22650.9 μmol min−1 mg−1 for EG-IV, respectively. Mn2+, Cu2+ and Pd2+ strongly inhibited the enzymes. EC-IV catalyzed the hydrolysis of Na-CMC and hydroxyethyl cellulose (HEC) only, whereas EG-III displayed high activity towards xylans, also. Different preferences towards cellulosic substrates and their regions define a different role of the investigated enzymes in the degradation of plant biomass. [ABSTRACT FROM AUTHOR]

The modern and rapidly developing paper and board industry requires more efficient agents for the surface of paper in order to improve the mechanical properties. The starch coating used for the reinforcement of schrenz (110 g/m2) contained ultrasonicated nanoparticles of the mineral sepiolite. The viscosity of starch dispersions modified with different concentration of sepiolite was followed at the temperature of the coating on schrenz. The values of the breaking length, bursting strength and CMT-strength of the paper reinforced with modified starch were increased by up to 20%. The viscoelastic properties as storage modulus were increased, too. Scanning electron microscopy of the samples showed deagglomeration and homogeneity of the sepiolite nanoparticles. [ABSTRACT FROM AUTHOR]

The present contribution evaluates the methods of degradation and stabilization of alum-containing paper with a focus on the alkaline environment achieved by deacidification procedures. In terms of reviewed subjects, the contribution focuses on alum-rosin sized paper, which is still used as a carrier of knowledge and information; however, it also mentions cellulose itself and other brands of paper. The contribution summarizes the results on the homogeneity of the distribution of alum and rosin in the paper mass and on the paper surface. It provides the knowledge gained in the field of alkaline hydrolysis and oxidation with special regard to transition metal species. It shows the values of alkaline reserves achieved in the main mass-deacidification processes. On the basis of the acquired knowledge, the contribution emphasizes the procedures of paper stabilization. Criteria of "increased mechanical permanence and lifetime prolongation" adopted to evaluate and compare the efficacy of individual mass-deacidification processes were applied and corresponding data are introduced. The contribution also draws attention to the existence of open issues in the area of paper degradation and stabilization. [ABSTRACT FROM AUTHOR]

Although degradation of iron gall ink containing paper has been scientifically studied for almost 250 years, we still do not have a good understanding of the kinetics of the process. While many studies focussed on model samples to avoid the inhomogeneity of real historic samples or the need for sampling, this research was conducted on a selection of real documents. Accelerated degradation experiments were performed at six combinations of temperature and relative humidity (RH) in the intervals 50–80 °C/20–80% RH. The analytical methods were optimised such that sample consumption was minimised and errors and uncertainties were evaluated. The results show that the rate of degradation, measured as change in the degree of polymerisation of cellulose in paper beneath ink, can be described in Arrhenius terms, and that the apparent activation energy for the process depends on the moisture content in the material. The variation is consistent with the process of hydrolysis becoming less prominent at lower moisture content values, although the results indicate that hydrolytic degradation predominates during natural ink-induced degradation. In the context of the historic samples used in the study, the presence of ink accelerated the degradation of paper by a constant factor of 1.59 in comparison to paper without ink, across the range of experimental T and RH. This indicates that a dose-response function could be developed for ink-induced degradation of paper. [ABSTRACT FROM AUTHOR]

Copyright of Slovenská Literatúra: Revue Pre Literárnu Vedu is the property of Institute of Slovak Literature 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.)

An approach was developed for the preparation of cryogenic ground spiked filter papers with Cu and Zn for use as synthetic calibrating standards for direct solid microanalysis. Solid sampling graphite furnace atomic absorption spectrometry was used to evaluate the microhomogeneity and to check the applicability of the synthetic calibrating standards for the direct determination of Cu and Zn in vegetable certified reference materials. The found concentrations presented no statistical differences at the 95% confidence level. The homogeneity factors ranged from 2.7 to 4.2 for Cu and from 6.4 to 11.5 for Zn. [ABSTRACT FROM AUTHOR]

Paper‐based surface‐enhanced Raman scattering (SERS) substrates have gained growing interest as an eco‐friendly and low‐cost tool for chemical and biosensing. However, paper‐based SERS substrates often suffer relatively low signal spatial homogeneity because of their nonuniform hot‐spot distribution. In this paper, a nanofibrillated cellulose paper (nanopaper) based SERS multiwell plate is developed for trace chemical detection with high sensitivity and high signal homogeneity. The SERS plate is fabricated from ultrasmooth (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl‐oxidized NFC paper (TO‐nanopaper) through wax‐printing‐based multiwell patterning followed by silver nanoparticle (AgNP) growth based on a successive ionic layer adsorption and reaction (SILAR) process. Taking advantage of the abundance of carboxyl groups on the TO‐nanopaper, uniformly distributed and densely arranged AgNPs are successfully synthesized through the SILAR process on the NFC multiwell surface under ambient conditions. The SERS performance of the device is evaluated for testing two Raman marker chemicals, rhodamine B and 2‐naphthalenethiol, and picomolar detection limit and high Raman enhancement factor (up to 1.46 × 109) are achieved. The Raman signal mapping results show superior signal spatial homogeneity of the device with low variations (≤11%). The nanopaper‐based SERS device represents a promising SERS platform for chemical and biomolecule detections with high sensitivity and high repeatability. [ABSTRACT FROM AUTHOR]

The classification of urban functional zones helps to understand the spatial structure of urban functions. However, achieving high classification accuracy is challenging, because of the complexity and randomness of urban components and their spatial distribution. An important idea in existing urban functional zone classification research is to extract the spatial context of points of interest (POIs) based on their spatial relationships, embed the POI representations, and then calculate the vector representation of the urban functional zones for classification. Important features that could be extracted from the spatial relationships between the POIs are the homogeneity and structural similarity between POIs. Although their important impact on urban functional zone classification has received attention, most studies construct urban functional zone classification methods that are based on the homogeneity of POIs. Limited studies combine them to construct urban functional zone classification methods. In this paper, a novel method for urban functional zone classification was proposed by integrating the homogeneity and structural similarity between POIs. First, the neighborhood structure of the POIs is defined based on the spatial relationships between POIs. Second, biased random walking strategies are designed to generate the spatial contexts of POIs. Third, the spatial contexts of the POIs are input into the Skip-Gram model to generate vectors for the POI types. Then, the vectors of urban functional zones are calculated. Finally, the support vector machine (SVM) is used for urban functional zone classification that is based on their vectors. The model was applied in Chaoyang District, Beijing. The feasibility, accuracy, and stability of the model were verified by comparing it with the Place2vec and the DeepWalk models. [ABSTRACT FROM AUTHOR]

To address complex issues, facilitated modelling aims to represent and accommodate plural worldviews from many stakeholders and experts. In these contexts, group homogeneity can become problematic when participants' plurality of perspectives and information is missing and people attending facilitated sessions have similar problem perceptions and interests. This is a challenge because it can lead to narrow discussion, groupthink and undermine output quality. Despite not being uncommon, effective approaches to deal with homogeneity are hardly reported. This paper presents a new role—the New Devil's Advocate—in which some facilitators leave their neutrality-oriented stance and act as the missing stakeholders. The paper illustrates a first application to a group model building process aimed at supporting the development of energy efficiency policies in the UK. To evaluate the results, workshop transcripts were coded, participants' and facilitators' feedback collected, and the modelling output assessed with respect to the New Devil's Advocate interventions during the workshop. Although the role performance appears to increase facilitators' workload and be influenced by role performers' personality and background, the analysis shows positive results as a promising practice to address homogeneity. Additionally, it offers a practical experience of how facilitation teams may temporarily abandon neutrality and intervene on content. [ABSTRACT FROM AUTHOR]

Purpose: This paper focuses on First Peoples Founders of for-profit entities in Australia and the role of the Indigenous Economic Development Agencies (IEDAs). We explore the challenges facing First Peoples enterprises, influenced by historical exclusion from white settler society, and the practices of the IEDAs from the perspectives of Founders and agencies. Design/methodology/approach: A qualitative study utilising Indigenous Standpoint Theory and Indigenous research methods, elevating Founder perspectives, in the Yaruwu language - the Nilangany Ngarrungunil, owners of knowledge, to that of research collaborators. Findings: The First Peoples economic landscape is continually evolving with IEDAs contributing to that evolution despite contentious identity ownership definitions. Founders secure in their own identity, are focused on self-determination and opportunities provided by IEDAs, government and corporate sector policies. However, opportunities are undermined by ongoing racism, discrimination and prevailing stereotypes leading to homogeneity, invisibility and exclusion. Founders question organisational commitments to overcoming systemic exclusion in particular their commitment to building respectful relationships and understanding First Peoples ways of working. Instead, Founders focus on building a sustainable First Peoples economic ecosystem through relationship-based practices rather than transactional reconciliation which ignores the reality of the lived experience of everyday racism. Originality/value: This study extends the scholarly discourse on First Peoples for-profit enterprise success written with an Indigenous voice. We demonstrate how this Founder generation are strengthened by culture with identity infused in organisational practices underpinning their aspirations of economic self-determination. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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 is focused on investigation of dielectric properties of various substrates for InkJet printing technology. In addition this paper included investigation of dielectric properties' homogeneity. Dielectric constant and loss tangent of polymeric flexible substrates (Polyimide DuPont Kapton HN, PET Mylar A, PEN Teonex Q51) and insulation paper (Nomex 410) were measured in GHz frequency area. Measurements were done by combination of vector network analyzer and split cylinder resonator. This measuring method provides dielectric properties at frequency around 10 GHz, the exact value of frequency may vary depends on specific material and its resonant frequency. Experiments included two types of samples, 6 x 6 cm which is recommended area for measurements of dielectric properties by split cylinder resonator and 12 x 12 cm for measurements of dielectric properties' homogeneity (one sheet contains 9 overlapping measuring areas 6 x 6 cm). All measured values of dielectric constant and dielectric losses were statistically processed and depicted by SigmaPlot software. The paper shows values of dielectric properties at GHz frequency area as they are lacking in datasheets from manufacturers and evaluate homogeneity of measured substrates. [ABSTRACT FROM AUTHOR]

In this paper, we examine topological partitions of topological spaces that arise in connection with continuous mappings of topological spaces. The content of the paper is closely related to such classical fundamental concepts of general topology as compactness, homogeneity, and Čech completeness. New facts related to these concepts are obtained. [ABSTRACT FROM AUTHOR]

This paper measures the stability of cross-linguistic register variation. A register is a variety of a language that is associated with extra-linguistic context. The relationship between a register and its context is functional: the linguistic features that make up a register are motivated by the needs and constraints of the communicative situation. This view hypothesizes that register should be universal, so that we expect a stable relationship between the extra-linguistic context that defines a register and the sets of linguistic features which the register contains. In this paper, the universality and robustness of register variation is tested by comparing variation within versus between register-specific corpora in 60 languages using corpora produced in comparable communicative situations: tweets and Wikipedia articles. Our findings confirm the prediction that register variation is, in fact, universal. [ABSTRACT FROM AUTHOR]

Collimated flat-top beam shapers primarily consisting of freeform lenses have a wide range of applications and pose challenges in terms of processing and integration when the diameter is less than millimeters. Metasurfaces represent a promising solution to planarize optics, can mimic any surface curvature without additional fabrication difficulty, and are suitable for flat-top optics. The conventional metasurface design approach relies on imparting the required phase using meta-atoms and encounters challenges in amplitude modulation due to near-field coupling and varying transmittances among meta-atoms with different phases, making the design of flat-top beam shapers difficult. In this paper, we propose a complex-amplitude constraint Gerchberg–Saxton algorithm for designing a collimated flat-top beam shaper metasurface doublet, which avoids the influence of strong near-field coupling on the amplitude distribution and simultaneously considers the amplitude-phase characteristics of the meta-atoms. A collimated flat-top beam with exceptional homogeneity Up of approximately 0.01, a wavefront error less than 0.1λ, and a transmittance higher than 86 % is experimentally obtained, comparable to commercial products based on freeform lenses. A collimated flat-top beam shaper metasurface doublet for generating flat-top beam is introduced, promoting efficient integration with laser systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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.)

The comprehensive review of research literature in accordance with the implementations of the accident causation models enables knowledge incomes for the contributing authors towards the advancement of the accident causation methodologies for administering the accidents' causal factors. For obtaining this objective, the systematic literature review meta‐analysis are developed by evaluating the parameter indicator linked to the most utilized causation methods in addressing the contributing factors in process industries. The methodological review process called preferred reporting items for systematic reviews and meta‐analyses (PRISMA) is implemented in this paper due to its capability to integrate both systematic reviews and meta‐analysis. This systematic literature review deeply investigates 149 papers by a thorough reading from the filtered 387 manuscripts published in the academic SCOPUS databases during 1980–2020. Additionally, the statistical analysis t test is performed to identify the homogeneity of literature papers resulting from research conclusions. The suggested future improvement in the domain of accident causation models is the advancement of administering the accident causal factors' values of correlations and interdependencies. While particularly for quantified accident causation models, the adoption of uncertainty analysis needs to further developed as a research suggestion in the future. [ABSTRACT FROM AUTHOR]

High brittleness materials such as ceramics and semiconductors are prone to fracture during cooling. Improving the sintering quality of such materials has been a problem explored by industry and scientific research. Here, the high brittleness semiconductor Zn4Sb3 was prepared by hot-press sintering. It was found that adding protective aluminum sheets with a similar expansion coefficient of Zn4Sb3 can significantly improve the sintering success rate of Zn4Sb3. The density and compositional homogeneity of the Zn4Sb3 were also significantly improved by the addition. The finite element simulation found the greatest increase in density when the thickness ratio of the sintered sample to the aluminum sheet was 1:1. The increase in density is due to the reduced stress during the cooling process and more uniform stress distribution on the sample. The improvement in composition homogeneity is due to the higher thermal conductivity of the aluminum sheets, which results in a smaller temperature difference inside the sample. In addition, the protective effect of the aluminum sheets reduces the volatilization of Zn. Materials with similar melting points have similar thermal expansion coefficients. High-quality sintering of brittle materials will no longer be difficult as long as a suitable sample protection material is found. [ABSTRACT FROM AUTHOR]

Keywords: chemical analysis and biosensing; nanofibrillated cellulose; nanopaper; paper-based device; surface-enhanced Raman scattering (SERS) A low-cost nanopaper SERS multiwell plate is fabricated by taking advantage of the SILAR process, which provides an ultra-high enhancement factor and excellent signal homogeneity. Chemical analysis and biosensing, nanofibrillated cellulose, nanopaper, paper-based device, surface-enhanced Raman scattering (SERS). [Extracted from the article]

Compressed and stabilized earth block (CSEB) masonry is a locally appropriate alternative for low-rise dwellings that offers attractive affordability, sustainability, and durability features. From a designer's perspective, the availability of standards for material characterization and design codes is essential for CSEB masonry to be accepted and adopted. However, current standards and codes are limited—this is certainly the case in North America—and largely rely on empirical and prescriptive provisions that are adapted from those for conventional masonry (e.g., fired-clay or cinder-block). Advancing standardization and codification calls for advances in the fundamental understanding of material and structural behavior as a function of constituents and manufacturing methods. For CSEBs that are customarily compacted using metallic molds and hydraulic presses, a fundamental gap lies in the understanding of whether the heterogeneity of stabilized soil mixtures, together with their manufacturing process, result in block materials that can be approximated as homogeneous and isotropic at the scale of specimens used for physicomechanical characterization. This paper reports on an investigation of a CSEB material whose constituent properties and manufacturing process are representative of those frequently encountered in North America. Homogeneity and isotropy are established based on empirical evidence from microscopic and chemical analysis, and on the statistical analysis of uniaxial compressive strength and stiffness data obtained from samples that were extracted from different areas of different source blocks, and then tested by applying loads parallel or perpendicular to the compaction direction. [ABSTRACT FROM AUTHOR]

This paper explores a new approach to improving satellite measurements of cloud optical thickness and droplet size by considering the radiative impacts of horizontal heterogeneity in boundary-layer cumulus clouds. In contrast to the usual bottom-up approach that retrieves cloud properties for individual pixels and subsequently compiles large-scale statistics, the proposed top-down approach first determines the effect of 3D heterogeneity on large-scale cloud statistics and then distributes the overall effects to individual pixels. The potential of this approach is explored by applying a regression-based scheme to a simulated dataset containing over 3000 scenes generated through large eddy simulations. The results show that the new approach can greatly reduce the errors in widely used bispectral retrievals that assume horizontal homogeneity. Errors in large-scale mean values and cloud variability are typically reduced by factors of two to four for 1 km resolution retrievals—and the reductions remain significant even for a 4 km resolution. The calculations also reveal that over vegetation heterogeneity-caused droplet size retrieval biases are often opposite to the biases found over oceans. Ultimately, the proposed approach shows potential for improving the accuracy of both old and new satellite datasets. [ABSTRACT FROM AUTHOR]

This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle (UAV) in the presence of parameter uncertainties, unmodeled uncertainties and wind disturbances. First, a fixed-time disturbance observer (FXDO) based on the bi-limit homogeneity theory is designed to estimate the lumped disturbance of the convertible UAV model. Then, a fixed-time integral sliding mode control (FXISMC) is combined with the FXDO to achieve strong robustness and chattering reduction. Bi-limit homogeneity theory and Lyapunov theory are applied to provide detailed proof of the fixed-time stability. Finally, numerical simulation experimental results verify the robustness of the proposed algorithm to model parameter uncertainties and wind disturbances. In addition, the proposed algorithm is deployed in a open-source UAV autopilot and its effectiveness is further demonstrated by hardware-in-the-loop experimental results. [ABSTRACT FROM AUTHOR]

Kathryn F. Porter wrote a nice paper about several definitions of local homogeneity [Local homogeneity, JP Journal of Geometry and Topology 9 (2009), 129–136]. In this paper, she mentions that G. S. Ungar defined a uniformly locally homogeneous space [Local homogeneity, Duke Math. J. 34 (1967), 693–700]. We realized that this notion is very similar to what we call the uniform property of Effros [On Jones' set function 풯 and the property of Kelley for Hausdorff continua, Topology Appl. 226 (2017), 51–65]. Here, we compare the uniform property of Effros with the uniform local homogeneity. We also consider other definitions of local homogeneity given in Porter's paper and compare them with the uniform property of Effros. We show that in the presence of compactness, the uniform property of Effros is equivalent to uniform local homogeneity and the local homogeneity according to Ho. With this result, we can change the hypothesis of the uniform property of Effros in Jones' and Prajs' decomposition theorems to uniform local homogeneity and local homogeneity according to Ho. We add to these two results the fact that the corresponding quotient space also has the uniform property of Effros. [ABSTRACT FROM AUTHOR]

Hyperspectral radiance measurements in the oxygen A band are sensitive to the vertical distribution of atmospheric scatterers, which in principle allows to retrieve aerosol height from future instruments like TROPOMI, OCO2, FLEX, and CarbonSat. Discussed in this paper is a fast and flexible forward operator for the simulation of hyperspectral radiances in the oxygen A band and, based on this scheme, a sensitivity study about the inversion quality of aerosol optical thickness, aerosol mean height, and aerosol type. The forward operator is based on a lookup table with efficient data compression based on principal component analysis. Linear interpolation and computation of partial derivatives is performed in the much smaller space of expansion coefficients rather then wavelength. Thus, this approach is computationally fast and at the same time memory efficient. The sensitivity study explores the impact of instrument design on the retrieval of aerosol optical thickness and aerosol height. Considered are signal to noise ratio, spectral resolution, and spectral sampling. Also taken into account are surface inhomogeneities and variations of the aerosol type. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Sustainable Development / Problemy Ekorozwoju is the property of Faculty of Environmental 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.)

In this paper, we study the maximal truncated singular integral operators with rough kernel along certain compound curves, which contain many classical model examples. We prove the Lp boundedness of such maximal singular integral operators under very weak conditions on the integral kernels both on the unit sphere and the radial direction. The main results essentially improve and extend certain previous results. [ABSTRACT FROM AUTHOR]

We present bottom gate staggered oxide semiconductor TFTs manufactured by using a highly selective wet-chemical backchannel etch step. To achieve stable contacts and great threshold voltage homogeneity we introduced oxygen barriers to suppress oxygen flow within the device. An AMLCD was realized to show the feasibility for industrial application. [ABSTRACT FROM AUTHOR]

Sensor-based human activity recognition has been widely used in various fields; however, there are still challenges involving recognition of daily complex human activities using sensors. In order to solve the problem of timeliness and homogeneity of recognition functions in human activity recognition models, we propose a human activity recognition model called 'BSTCA-HAR' based on a long short-term memory (LSTM) network. The approach proposed in this paper combines an attention mechanism and a temporal convolutional network (TCN). The learning and prediction units in the model can efficiently learn important action data while capturing long time-dependent information as well as features at different time scales. Our series of experiments on three public datasets (WISDM, UCI-HAR, and ISLD) with different data features confirm the feasibility of the proposed method. This method excels in dynamically capturing action features while maintaining a low number of parameters and achieving a remarkable average accuracy of 93 % , proving that the model has good recognition performance. [ABSTRACT FROM AUTHOR]