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Plant-fibre ancient-books with cultural significance should be protected from moisture and pollution. In this work, a strategy of surface in-situ protection (building composite coating) was adopted to achieve good hydrophobicity, moisture-proofness and ink-contamination resistance at the surface of archaistic paper. By pre-ring opening of epoxy-based poly(vinyl silsesquioxane) (POSS) and spray of POSS/polyvinylidene fluoride (PVDF) mixed solution, in-situ construction of POSS/PVDF composite coating at the surface of ancient paper was achieved. Compared to water-absorbing ancient paper, POSS/PVDF co-modified ancient paper shows strong humidity resistance. The surface of co-modified ancient paper (epoxy-group pre-ring opening for 45 min) displays high hydrophobicity (water contact angle of ~142.6°), ascribed to greatly improved surface roughness of paper fibres as well as complete coverage of high-content Si/F elements on fibre surface. POSS-modified and neat ancient-paper materials show surface water contact angles of ~113.9° and 0°, respectively. Robust ink-resistance of POSS/PVDF co-modified ancient-paper surface is realized. The innovation in this work lies in perfect synergy of cage-shaped POSS and threadlike PVDF in coating. This work might open a way for surface nondestructive-protection to ancient-books for damp-proof, hydrophobic and anti-fouling characteristics. [ABSTRACT FROM AUTHOR]

Paper and packaging materials a lignocellulose-based natural biodegradable polymer that spontaneously releases acetic acid, aldehydes, alcohol, and ester-based volatile organic compounds (VOCs) upon ageing and these VOCs start degrading the paper products and decline their mechanical strength properties. The reactivity of the paper of unbleached wheat straw pulp towards acetic acid and hexanal, which has been proven to have more degrading effects on paper than other VOCs, was considered in this work. The papers were exposed to these volatile compounds for 90 days in an air-tight vessel under ambient environmental conditions. The results showed that hexanal was more destructive than acetic acid with regards to cellulose degradation and depletion in the mechanical strength properties. The paper properties like, tensile, tear and burst index, viscosity, pH and carbonyl group content was measured. The growth of the carbonyl group, evidence of the ageing effects in the paper, detected more in the paper exposed to acetic acid. However, the strength of paper properties declined more with hexanal. FE-SEM analysis of the sample showed the development of pores and damage of cellulose fibre upon ageing. Similarly, the damaging effects of VOCs on cellulose, hemicelluloses and lignin were confirmed by significantly reduced peak detection through FT-IR \analysis. The high crystallinity index of the paper products due to exposure to VOCs was detected by XRD analysis, which confirmed the degradation of the low molecular weight cellulose molecule. Thus, the results are strongly recommended that VOCs that generates due to natural or artificial ageing could be the leading cause of paper degradation. [ABSTRACT FROM AUTHOR]

This paper presents the case of an adjunct university professor to illustrate the dilemma of using artificial intelligence (AI) technology to grade student papers. The hypothetical case discusses the benefits of using a commercial AI service to grade student papers—including discretion, convenience, pedagogical merits of consistent feedback for students, and advances made in the field that yield high-quality work—all of which are achieved quickly. Arguments against using AI to grade student papers involve cost, privacy, legality, and ethics. The paper discusses career implications for faculty members in both situations and concludes with implications for researchers within the discourse on academic integrity. [ABSTRACT FROM AUTHOR]

As China's demand for paper products increases, China's paper industry faces enormous pressure to reduce greenhouse gas emissions. By using material flow analysis in combination with input–output analysis, this study measured the waste paper recovery rate in a more accurate method and analyzed the impact of waste paper recycling on the carbon emissions from China's paper industry. China's waste paper recovery rate estimated in this study was close to 70% in 2017, much higher than that of 48% obtained with the traditional method. The regression results displayed a negative relationship between waste paper recovery rate and CO2 emissions per unit of paper consumption during 2000–2017 in China. The rolling regression results further indicated that the impact of waste paper recycling was becoming stronger on reducing CO2 emissions per unit of paper consumption in China. Since an inverted "U" shape relationship exists between waste paper recovery rate and its reduction effect on carbon emissions from the paper industry, the regression results suggested that China's waste paper recovery rate has not reached the optimal level with regard to carbon emissions from China's paper industry. Thus, although China's waste paper recovery rate has reached a relatively high level, currently waste paper recycling is still an effective method to reduce carbon emissions from China's paper industry. [ABSTRACT FROM AUTHOR]

This research focuses on the development of paper from lignocellulosic agricultural wastes, viz., corn husk (CH), which is an underexplored material and sugarcane baggase (SB), in varying proportions, through soda pulping and enhancement of their functionalities through chitosan and beeswax–chitosan emulsion coatings. Fiber digestion was done at optimized conditions; followed by blowing, quenching and then refining of both treated CH and SB pulp to a Canadian Standard Freeness (CSF) of 400–450 mL. The handsheets of 80 GSM (grammage) were prepared as per the standard ISO-5269/1 and were tested for their mechanical and barrier properties as per standard methods of ISO. Handsheets developed from the blend of SB and CH (50:50) and SB fibers (100%) were found to have better mechanical strength (in terms of burst, tensile and tear strength) in comparison to CH fibers (100%). The effect of coatings on mechanical, water resistance, micro-structural, and biodegradable properties of the cellulose papers were also assessed. The chitosan coating significantly improved (p < 0.05) the mechanical properties of papers, the barrier properties against water vapor, moisture and air were also enhanced (up to 85%). Papers coated with beeswax–chitosan emulsion had the longest absorbency time, followed by chitosan-coated and uncoated papers. The results advocated for beeswax–chitosan emulsion as the best among the coatings tested, for aforementioned cellulose papers to enhance their barrier properties. [ABSTRACT FROM AUTHOR]

During graduate education, postgraduates have to spend considerable time finding papers to explore the development branches of their field. However, existing paper recommendation methods focus on several attributes (title, author, keyword, venue, etc.). The network schema constructed by these attributes is extremely sparse, which easily causes the loss of important semantic paths between attributes. This results in a lack of correlations among relevant papers, which affects paper recommendation efficiency. Moreover, the relationships between multiple semantic paths can be found through common homogeneous and heterogeneous attributes. These relationships can establish many correlations among relevant papers. To address the above problems, this paper proposes a new approach to fuse multi-semantic paths into a heterogeneous educational network (HEN) for personalized paper recommendation. After data processing, a new HEN schema is built by enriching nodes and edges in heterogeneous networks. Then, different semantic meta-paths are generated by projection sub-nets. Next, a new HEN embedding method is proposed by multi-semantic path fusion to generate rich HEN node sequences. Finally, personalized paper recommendation for postgraduates by targeted path similarity. The proposed method was performed on two paper datasets in the fields of educational intergenerational mobility from 1987 to 2021 and data mining and intelligent media from 1997 to 2021. Substantial experiments demonstrate that the proposed approach is effective. [ABSTRACT FROM AUTHOR]

In this research, we design and implement a small, convenient, and noninvasive paper-based microfluidic sweat sensor that can simultaneously detect multiple key biomarkers in human sweat. The origami structure of the chip includes colorimetric and electrochemical sensing regions. Different colorimetric sensing regions are modified with specific chromogenic reagents to selectively identify glucose, lactate, uric acid, and magnesium ions in sweat, as well as the pH value. The regions of electrochemical sensing detect cortisol in sweat by molecular imprinting. The entire chip is composed of hydrophilically and hydrophobically treated filter paper, and 3D microfluidic channels are constructed by using folding paper. The thread-based channels formed after the hydrophilic and hydrophobic modifications are used to control the rate of sweat flow, which in turn can be used to control the sequence of reactions in the differently developing colored regions to ensure that signals of the best color can be captured simultaneously by the colorimetric sensing regions. Finally, the results of on-body experiments verify the reliability of the proposed sweat sensor and its potential for the noninvasive identification of a variety of sweat biomarkers. [ABSTRACT FROM AUTHOR]

An efficient process for recycling paper and cardboard wastes via dissolution in N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) system and regeneration from solutions to obtain hydrogels has been developed. Pretreatment of waste paper has been carried out by thermal defibrillation of waste paper in water and homogenization to obtain fibrous samples. The dissolution of fiber materials was performed in two ways by varying the process temperature and the way the reagents were added. Regeneration from solutions was carried out by spontaneous gelation without the use of antisolvents, at room temperature and atmospheric pressure. As a result, hydrogels were obtained which differed in color and transparency depending on feedstock. The physicochemical properties of the hydrogels were characterized. It was shown that they were steady in an aqueous medium, capable of retaining a significant amount of water (over 4000 wt %), and they were porous systems which was confirmed by scanning electron microscopy. According to a wide-angle X-ray scattering, the crystallographic structure of the pristine waste paper samples corresponded to a structural modification of cellulose I. Regenerated samples as freeze-dried hydrogels had the structure of cellulose II. A functional and an elemental composition studied with FTIR spectroscopy and an energy-dispersive X-ray microanalysis characterized these hydrogels as the cellulose samples containing small amount of inorganic impurities. The resulting hydrogels had a system of open pores of different sizes, and this predetermined their use as adsorbents and active matrices. [ABSTRACT FROM AUTHOR]

Background: Lignocellulosic biomasses produced from agriculture and forest-based industries are the cheapest or negative-cost biomass with a great potential for biotransformation to value-added bioproducts. Paper mill sludge, an important lignocellulosic biomass creates an environmental threat, which requires financial input for disposal. Thus, this study was aimed to isolate a novel bacterial strain capable of degrading cellulosic biomass including paper mill sludge to produce reducing sugar and other value-added bioproducts. Results: A novel bacterial strain Arthrobacter woluwensis TDS9 isolated from the soil was screened for its cellulolytic activity using carboxymethyl cellulose (CMC) as the sole carbon source. The incubation period, temperature, pH, carbon, and nitrogen sources are the most important factors ruling the CMCase and sugar productions of the strain A. woluwensis TDS9, and an alkaline pH (pH 8.0) led to enhanced sugar production up to 1100.09 μg/mL after 72 h of incubation at 25°C in a medium containing 1.5% CMC and 1.25% beef extract. The optimal conditions for maximum CMCase activity were defined, and the potassium ion boosted the CMCase activity up to 1.06 U/mL when the enzymatic reaction was performed for 30 min at 50°C and pH 8 using CMC as a substrate. Moreover, the strain A. woluwensis TDS9 produced 433.33 μg/mL reducing sugar from 1% pretreated paper mill sludge. Significant alterations in the structural arrangement of cellulosic fiber of paper mill sludge observed under microscope after each step of chemical treatment process helped for loosening the cellulose fibers and increased the saccharification for enzymatic hydrolysis. Endoglucanase IV (33 KDa) and beta-glucosidase II (53 KDa) were identified in crude enzyme based on the zymogram analysis and substrate specificity. Conclusions: The research has for the first time proved that this A. woluwensis TDS9 strain can efficiently convert cellulose. Therefore, the strain TDS9 could be a potential candidate for cellulase production in an industrial biotransformation process of paper mill sludge to produce reducing sugar. This sugar stream can be further used as a substrate to produce biofuels and other organic acids using another microorganism, which represents a greener alternative to add value to the paper production helping paper mill industries. [ABSTRACT FROM AUTHOR]

Nanozymes are nanomaterials that possess intrinsic enzyme mimicking activity. In this study, the application of silver nanoparticles coated filter paper (AgNPs/FP) that exhibits a peroxidase-like catalytic activity as a potential sensor is reported. A simple chemical reduction method was used to produce AgNPs/FP. The formation of the particles on filter paper were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and surface-enhanced Raman spectroscopy (SERS). In the presence of hydrogen peroxide, AgNPs/FP oxidized the colorless o-phenylenediamine (OPD) and 3,3′,5,5′-tetramethylbenzidine (TMB) solutions to a yellow colored 2,3-diaminophenazine (DAP) and deep blue colored oxidized TMB (oxTMB), respectively. In the presence of thiocyanate, however, the peroxidase-like activity was inhibited in a concentration dependent manner. This makes the AgNPs/FP a promising catalyst and employed for colorimetric detection of thiocyanate via inhibition of the peroxidase-like activity. The application can be further extended to other environmentally and biologically important analytes. [ABSTRACT FROM AUTHOR]

Paper-based electronics have attracted much attention due to their softness, degradability, and low cost. However, paper-based sensors are difficult to apply to high-humidity environments or even underwater. Here, we report a fully paper-integrated piezoresistive sensing system that exhibits flexibility, waterproofing, air permeability, and biocompatibility. This system consists of hydrophobic paper as the substrate and encapsulation layer, conductive paper with a double 'zig-zag' and dotted surface structure as the sensing layer, and silver paste films as the interconnects. The structural design of the sensing layer helps to increase the contact area in adjacent layers under pressure and further improves the pressure sensitivity. The piezoresistive system can be worn on human skin in the ambient environment, wet environment, and water for real-time monitoring of physiological signals with air permeability and waterproofing due to its hydrophobic fiber structure. Such a device provides a reliable, economical, and eco-friendly solution to wearable technologies. [ABSTRACT FROM AUTHOR]

Due to the hydrophilic nature of paper mulch, it is easy to absorb water during use, which will reduce its mechanical properties and durability, thus affecting its performance. Therefore, the development of paper mulch is hindered. In this paper, in order to improve the hydrophobic performance of paper mulch, we successfully prepared superhydrophobic silicon dioxide/paper mulch by simple, efficient and environmentally friendly solution immersion method without the introduction of adhesive. The contact Angle and rolling Angle between the prepared super hydrophobic paper mulch and water are 156.4° and 1.8°, respectively. The water drop is easy to roll on its surface, and has excellent water drop bouncing performance, which can play an excellent water-repellent function. Studies have shown that the superhydrophobicity of silicon dioxide/paper mulch is less affected by its surface roughness, mainly because the surface covered by a layer of silicon dioxide reduces the surface energy of the paper mulch, and the silicon dioxide on the surface of the paper mulch is enough to reduce the damage of aging on the paper mulch. In addition, the decrease in the contact angle of the SiO2/paper mulch and the increase in the rolling angle after aging are due to the decrease in the amount of SiO2 adhesion on the surface of the paper mulch and the increase in the degree of exposure of fiber bundles. Studies have found that the superhydrophobic paper mulch can reduce the influence of its own aging on its rolling angle after being subjected to friction. [ABSTRACT FROM AUTHOR]

This research uses WP to investigate the effect of two types of Shredded Waste Paper (SWP) comprising Shredded Copier Waste Paper (SCPWP) and Shredded Cardboard Waste Paper (SCBWP) as additives on the properties of concrete and the structural behaviour of Reinforced Concrete Beam (RCB). The slump, compressive, flexural, and splitting tensile strengths increase by 4–13% for 5–10% addition of SCPWP and decrease by 16–23% for 15% addition of SCPWP compared to 0% addition. For SCBWP, the slump, compressive, flexural and splitting tensile strengths increase by 10–23% for 5–10% addition and decrease by 15–21% for 15% addition compared to 0% addition. 15% of SCPWP and SCBWP addition records the highest effect in water absorption and efflorescence, showing 11% and 10.28% increases with 15% addition of SCBWP and SCPWP. Scanning electron microscope (SEM) analysis reveals that the crack is repaired, and the presence of calcium hydroxide (Ca(OH)2) and calcium–silicate–hydrate (C–S–H) links enhances the concrete strength. The addition of 10% SCPWP and 10% SCBWP in the concrete mixtures improves the structural behaviour of RCB with stirrup spacing (SS) = 100 mm (full), 150 mm and 200 mm (reduced) by increasing the load and reducing the deflection. Apart from that, the concrete bending and shear strains also increase by 44.17% and 34.9%. The failure mode of the RCB changes from shear to bending. This study indicates that SCPWP and SCBWP can be used as additives in concrete at 5% and 10%, and 10% for RCB with significant strength and structural improvement. [ABSTRACT FROM AUTHOR]

Key summary points: Aim: To describe the evidence on the usefulness of a Comprehensive Geriatric Assessment (CGA)-based approach during the COVID-19 pandemic. Findings: The multidimensional, CGA-based approach allows better identification of individual risk profiles and frailty status of infected, recovered but with a post-COVID-19 condition, and non-infected older adults. Message: Capturing older patients' needs through CGA may offer the possibility to guide clinical decision and implement personalized medicine. Purpose: The COVID-19 pandemic has been a dramatic trigger that has challenged the intrinsic capacity of older adults and of society. Due to the consequences for the older population worldwide, the Special Interest Group on Comprehensive Geriatric Assessment (CGA) of the European Geriatric Medicine Society (EuGMS) took the initiative of collecting evidence on the usefulness of the CGA-based multidimensional approach to older people during the COVID-19 pandemic. Methods: A narrative review of the most relevant articles published between January 2020 and November 2022 that focused on the multidimensional assessment of older adults during the COVID-19 pandemic. Results: Current evidence supports the critical role of the multidimensional approach to identify older adults hospitalized with COVID-19 at higher risk of longer hospitalization, functional decline, and short-term mortality. This approach appears to also be pivotal for the adequate stratification and management of the post-COVID condition as well as for the adoption of preventive measures (e.g., vaccinations, healthy lifestyle) among non-infected individuals. Conclusion: Collecting information on multiple health domains (e.g., functional, cognitive, nutritional, social status, mobility, comorbidities, and polypharmacy) provides a better understanding of the intrinsic capacities and resilience of older adults affected by SARS-CoV-2 infection. The EuGMS SIG on CGA endorses the adoption of the multidimensional approach to guide the clinical management of older adults during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]