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Abstract Gels prepared from the polysaccharide gellan are used for aqueous poulticing treatments in paper conservation when the application of water must be restricted. Optimal use of the rigid, yet shapeable gel requires direct contact with the paper surface, which carries the risk of gel residues on the treated surface. We used acid methanolysis as a destructive analytical method to detect rhamnose as a component of gellan, which was undetectable with ATR-FTIR spectroscopy. We show that there is a significant probability of leaving gellan residues on the paper. Conservators should be aware of this potential side effect when considering the use of gellan poultices in direct contact with paper objects.

This article presents the information on the valorization of waste generated during the production of tissue paper. The possibility of bioconversion of the polysaccharide part of paper sludge into simple sugars has been evaluated. The options for processing the paper sludge before enzymic hydrolysis to achieve the maximum yield of monosaccharides have been considered. Pretreatment with acids has been found to be a key step before the biocatalytic cleavage of waste polysaccharides. An additional yield of enzymic hydrolysis products after pretreatment with acids has been obtained by pre-extraction of the paper sludge with spirit or acetone. It has been established that the most intense enzymic hydrolysis of readily available fractions of the paper sludge takes place in the first 10–12 hours. Further, the process slows down, probably due to the action of the remaining components of the fillers, as well as an increase in the proportion of the difficult-to-hydrolyze polysaccharide part. In all cases, the proportion of absolutely dry non-hydrolyzed residue has been about 43±2 % of the dry matter of the paper sludge. The main products of enzymic hydrolysis have been glucose and xylose. The resulting sugars have been used for mixotrophic cultivation of the Tetradesmus obliquus and Chlorella vulgaris algae. Yeast strains have been selected for the conversion of monosaccharides from the paper sludge. In a series of experiments on non-sterile yeast cultivation, the Candida utilis PAL D and Debaryomyces hansenii SWING R cultures have turned out to be the most productive (within 2.10±0.14 g of air-dry yeast weight/dm3 per 24 hours). The degree of conversion of hydrolysate sugars has been 70±2 %. Most of the remaining sugars (about 80 %) have been represented by xylose. Complete utilization of the sugars has taken place on the 2nd day when having added an extra nitrogen source to the medium. On the other hand, the spent nutrient medium after yeast separation has been suitable for mixotrophic cultivation of microalgae. It has been revealed that the economic costs of pre-treatment of the paper sludge with nitric acid can be leveled by using the resulting salts as a nitrogen source for cultivating yeast. In doing so, the yield of yeast biomass increases by almost 2 times.

Size presses on paper machines are used to apply a solution of a polymer – usually starch – to the surface of the sheet and thereby to increase the stiffness, surface strength, and printing quality of the product. This article reviews publications dealing with the size press equipment, the materials, and factors affecting both the operating efficiency and attributes of the resulting paper. The emergence of film-press equipment (e.g. blade-metering size presses) in the 1980s has greatly decreased the frequency of web breaks and increased productivity. Starch technology at the size press, though relatively mature, continues to evolve. By adjustment of starch attributes, solids levels, and incorporating other additives, modern papermakers can tune size press outcomes to meet a range of paper product requirements, including strength, hydrophobicity, and the reduction of air permeability. By application of various synthetic polymers, mineral particles, and even nanocellulose in combination with starch or other base polymers, there is potential to extend the technology to meet a range of future needs for paper products.

Abstract To compare the urine Congo‐red dot paper test (CRD) with dipstick urinalysis to screen preeclampsia (PE). A total of 409 paired spot urine samples were obtained prospectively from women with suspected pre‐eclampsia attending for routine hospital visits. Congo‐red dot paper test and dipstick urinalysis were examined and compared to screen pre‐eclampsia. The agreement between the two urinary test is modest (kappa coefficient = 0.28, 95% CI 0.14–0.42). The specificity of CRD was higher than urinalysis (97.4% vs. 90.4%, p

Contemporary ESL education focuses on screen-based reading, specifically in the context of university level learners. Also, a sudden shift from paper bound reading activities to screen-based tasks was inevitable in response to COVID-19 outbreak. In this regard, the case of inferential and advanced level reading among the young ESL learners of developing countries appears researchable because of the general low digital literacy of these learners. This study, therefore, aimed to investigate the effect of reading mode shift from paper to screen on the inferential comprehension performance among Pakistani ESL learners at university level. A total of 426 undergraduate learners were sampled from Bachelor of Science program in a well-known university in the city of Lahore, Pakistan. Inferential reading was conceptualized through Bloom’s higher order thinking skills, that is, Analyzing, Evaluating and Creating skills therefore the reading comprehension test was based on these skills. Adopting sequential test administration, first the paper-based reading test, and later the screen-based reading was given. The obtained data were analyzed using Rendell’s XCALIBRE and SPSS V. 26.0. The logit scale descriptives, learner ability (θ), and mean scores demonstrated that the learners performed significantly higher in the paper test as compared to screen test. Moreover, it was found that the effect of reading mode shift was larger in Creating skill. The findings may have significant implications for reading mode selection, enhancement of digital competence and effect of reading mode shift in developing countries with inadequate IT facilitation and digital literacy among ESL learners.

The present study was conducted to draw the co-authorship network of hot papers of science citation index in the Web of Science (WOS) database from 2020 to 2021. This investigation is a descriptive study using a scientometrics approach. This research was conducted using social network analysis indices to visualize the co-authorship networks of hot papers in the science citation index. The structure of the co-authorship network of researchers of hot papers in the field of science consists of 47,045 authors who have contributed to the publication of 3475 hot papers from 2020 to 2021, which indicates the high co-authorship of these authors. Moreover, it was found that among the co-authorship patterns of these researchers, the most significant number of articles during the studied years was related to the five-author collaborations. Moreover, the average Collaboration Coefficient (CC) of the authors of hot papers was higher than 0.80, indicating the authors' strong tendency to produce joint articles. The high collaboration of the authors of hot papers in the science citation index can be one of the reasons for increasing the level of visibility and the potential for using them.

Reliable data on U.S. paper and cardboard waste by location and type are critical for developing waste-reduction solutions, but detailed geographic analysis is lacking in the literature. In this study, we employ statistical and geospatial methods to assess paper and cardboard waste in the United States by type at the national, state, county, and local levels. Of the estimated 110 million tons of paper and cardboard waste managed domestically in 2019, approximately 56% was landfilled, 6% was combusted, and 38% was recycled. The estimated market value of paper and cardboard lost to landfilling in 2019 was $4 billion, and the estimated losses of embodied energy and combustion energy were equivalent to 9% and 4% of U.S. primary industrial energy consumption, respectively. Associated landfilling fees amounted to almost $4 billion. This study aims to inform efforts to implement beneficial waste-management strategies by policy makers, researchers, businesses, and communities across the United States and to provide a model for similar studies in other parts of the world.

Introduction: Monitoring the atypical antipsychotic drug clozapine is crucial to ensure patient safety. This article showcases a high-throughput analytical method for measuring clozapine and its primary metabolite norclozapine (N-desmethylclozapine) in serum using paper spray mass spectrometry (PS-MS). Objectives: This study aimed to assess the viability of a PS-MS method for the rapid measurement of clozapine and norclozapine in human serum samples as an alternative to liquid chromatography mass spectrometry (LC-MS). Methods: Serum samples were processed by protein precipitation followed by deposition of the supernatant containing labelled internal standards onto paper spray substrates mounted in cartridges. Analytes were then analyzed using a triple quadrupole mass spectrometer equipped with a commercial paper spray ionization source. The results obtained from the patient samples were compared to those from a validated LC-MS assay. Results: PS-MS calibrations for clozapine and norclozapine were linear (R2 > 0.99) over five days. Between-run precision was below 8 %, and within-run precision did not exceed 10 %. When compared to a validated LC-MS method, the mean bias for 39 patient samples was −9% for clozapine and −1% for norclozapine, with no outliers. Mass spectrometry ion ratio comparisons indicated no interference for patient samples above the lower limit of quantification. There was less than 7 % change in the measured concentrations of both analytes over five days for samples dried on paper substrates. Notably, virtually no maintenance of the MS source was required during this study. Conclusion: This study illustrates the potential of PS-MS for serum drug monitoring in the clinical laboratory.

Besides scientific impact, papers can also achieve a technological impact that remains less known in the scientific community. Cited papers in the patents are considered as the index to measure the technological impact. This study aimed to analyze the technological impact of Iranian publications using co-authorship and co-word map, their evolution, the journals, and the subject areas of these publications. This applied research focuses on the quantitative study and visualization with a scientometric approach. The research population was all studies (4554 records) that were published during 2011-2020 in one of the Iranian institutions and had been cited by one of the international patents. The data collection tool was the SciVal database. CiteSpace and Excel spreadsheets were used to analyze the data. Of the 4,554 papers cited by the scholarly outputs that have been cited in patents e patents, most of them were published in collaboration with the USA (9%). Islamic Azad University and Tehran University of Medical Sciences (13% each) were the most active Iranian universities. The number of Iranian papers cited in patents had a downward trend from 686 in 2011 to 57 in 2020. RSC Advances journal was the first top journal to publish these papers. Of 27 subject areas, engineering (24.1%) was the first popular subject that patents cite in their publications. The cluster analysis of keywords identified 8 clusters, including “x-ray diffraction,” “animal,” “adult,” “escherichia coli,” “tissue engineering,” “coronavirus infection,” “neural network,” and “methane.” The technological impact of Iranian research has declined in recent years. It is suggested that research policymakers should consider scholarly outputs that have been cited in patents, which, in a way, shows the flow of knowledge to the industry and encourages researchers to produce such papers.

Abstract Soot stain from diverse sources is the most common stain that stains historical paper documents found in libraries, museums, and storage facilities. It is believed to be one of the types of deterioration that arises from the contact between stains and paper sheets. Therefore, in the present work, the effectiveness of the synthesized hybrid nanogel consisting of carbopol and nanoparticles (NPs) of ZnO, TiO2, or Fe3O4, in low and high-viscosity forms, for eliminating soot stains from historical paper manuscripts was conducted. The prepared hybrid nanogels were characterized utilizing the TEM, AFM, XRD, DLS, and Zeta Potential techniques. Following preparation, the soot-stained paper samples were heated to 105 °C for 6 days, a process known as accelerated thermal aging. Surface morphology, mechanical properties and the color change of the paper samples were investigated. The prepared hybrid nanogel had a spherical shape with well-defined edges and uniform size, with an average particle diameter ranging from 30 to 35 nm. There was no significant NPs agglomeration seen, suggesting uniform dispersion in the carbopol matrix. Additionally, the prepared gels' crystal structure and phase purity were revealed by the XRD analysis results. Paper fibers were visible in some parts of the treated sample with TiO2/carbopol hybrid nanogel at high-viscosity before aging. Cleaning soot-stained paper samples using high-viscosity Fe3O4/carbopol hybrid nanogel is more successful than using low-viscosity nanogel. the sample treated with high-viscosity ZnONPs/carbopol hybrid nanogel produced the highest total color differences (ΔE) (26.17). The paper sample treated with high-viscosity ZnO/carbopol hybrid nanogel exhibited the maximum tensile strength (61.8 N/mm2) and elongation at break (1.174%). The evaluation of the paper samples both before and after the cleaning process revealed that, the treatment with high-viscosity ZnO/carbopol hybrid nanogel gave the best results in removing soot stains from stained paper samples.