bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Effective Policy Implementation Affect Municipal Solid Waste Management in Bandung?
Authors: Keita Sandi
Published: May 2024

The continuous increase in generation and volume of solid waste  in cities including Bandung could severely have a negative effect on health of the population and  on the environment. This phenomenon is expected to continue as the population of Bandung keeps growing due to urbanization. However, the city government of Bandung formulated regional waste management regulation. while regional cleaning company PDK was tasked and subsidized by the city government to carry out the implementation of waste management regulation of the city. The implementation of the regulation and the management of waste is analyzed using descriptive and quantitative analysis methods. The results of the analysis shows that the regulations are not effectively implemented and the waste management is affected by lack of adequate infrastructure, human resource, public awareness and technology.
Performance Evaluation of Bentonite/Nano-SiO2 Composite as Bleaching Earth in Crude Palm Oil Processing
Authors: Yahya Agung Kurnia , Nurmalasari Enny , Aini Apsari Puspita , Ulya Hana Nikma
Published: May 2024

In crude palm oil (CPO) processing industries, bleaching is important to remove unwanted impurities. Most industries use various bleaching earth with 0.8-2% w/v concentration during the bleaching process. As bleaching earth is single-used for the bleaching process, materials with higher adsorption ability are preferable to reduce the use of bleaching earth. This study aimed to evaluate the performance of bentonite/nano SiO2 composite (BE-SiO2) as bleaching earth in the bleaching process of CPO. The prepared BE-SiO2 was used in the bleaching process with various BE-SiO2 concentrations (0.1-1.3% w/v), process duration (0-2.5 hours), and process temperature (70-150°C). From the results, the rise in BE-SiO2 concentration during the CPO bleaching process initially led to a decrease in the β-carotene concentration, acid content, free fatty acids (FFA), and DOBI number up to 1% w/v of BE-SiO2. Subsequently, these parameters exhibited an increase with the addition of BE-SiO2. The bleaching process effectively reduced the β-carotene concentration, acid content, FFA, and DOBI number within the first 1.5 hours of operation. While a higher amount of β-carotene was adsorbed during the adsorption process at higher temperatures, the bleached palm oil (BPO) quality was compromised due to the heat. The results showed that the most effective condition of the bleaching process was performed with 1% w/v BE-SiO2 concentration for 1.5 hours at 90°C. From those conditions, the BPO had a β-carotene concentration of 312.311 ppm, water content of 0.112%, acid number of 0.0076, FFA of 4.864%, DOBI number of 1.311, and red/yellow of 1.5/15.
Evaluation of renal sodium handling in heart failure with preserved ejection fraction: A pilot study
Authors: Agarwal Adhish , Beddhu Srinivasan , Boucher Robert , Rao Veena , Ramkumar Nirupama , Rodan Aylin R. , Fang Jacob , Wynne Brandi M. , Drakos Stavros G. , Hanff Thomas , Cheung Alfred K. , Fang James C.
Published: May 2024

The pathophysiology behind sodium retention in heart failure with preserved ejection fraction (HFpEF) remains poorly understood. We hypothesized that patients with HFpEF have impaired natriuresis and diuresis in response to volume expansion and diuretic challenge, which is associated with renal hypo‐responsiveness to endogenous natriuretic peptides. Nine HFpEF patients and five controls received saline infusion (0.25 mL/kg/min for 60 min) followed by intravenous furosemide (20 mg or home dose) 2 h after the infusion. Blood and urine samples were collected at baseline, 2 h after saline infusion, and 2 h after furosemide administration; urinary volumes were recorded. The urinary cyclic guanosine monophosphate (ucGMP)/plasma B‐type NP (BNP) ratio was calculated as a measure of renal response to endogenous BNP. Wilcoxon rank‐sum test was used to compare the groups. Compared to controls, HFpEF patients had reduced urine output (2480 vs.3541 mL; p = 0.028), lower urinary sodium excretion over 2 h after saline infusion (the percentage of infused sodium excreted 12% vs. 47%; p = 0.003), and a lower baseline ucGMP/plasma BNP ratio (0.7 vs. 7.3 (pmol/mL)/(mg/dL)/(pg/mL); p = 0.014). Patients with HFpEF had impaired natriuretic response to intravenous saline and furosemide administration and lower baseline ucGMP/plasma BNP ratios indicating renal hypo‐responsiveness to NPs.
Using Bland-Altman plot-based harmonization algorithm to optimize the harmonization for immunoassays
Authors: Fang Huiling , Yang Ruifeng , Guo Jiayue , Ren Xinxin , Chang Xin , Kang Lan , Zhu Yuqing
Published: May 2024

Objectives

Harmonization has been recommended by the International Organization for Standard (ISO) to achieve equivalent results across in vitro diagnostic measurement devices (IVD-MDs). We aim to evaluate the effectiveness of Bland-Altman plot-based harmonization algorithm (BA-BHA) created in this study and compare it with weighted Deming regression-based harmonization algorithm (WD-BHA) proposed in ISO 21151:2020.

Methods

Eighty patient sera were used as the harmonization reference material (HRM) to develop IVD-MD-specific harmonization algorithms. Another panel of 40 patient sera was used to validate the effectiveness of harmonization algorithms. We compared regression slopes, intercepts, Bland-Altman plot layouts, percent differences, limits of agreement (LoAs), between-method coefficients of variation (CV) before and after harmonization.

Results

After harmonization by WD-BHA, acceptable slopes and intercepts between measured values and HRM targets were observed in weighted Deming regression, but not in Passing-Bablok analysis. Mean differences were −5.5 to 5.0 % and differences at specific levels were −33.9 to 23.9 %. LoAs were −64.6 to 74.6 %. Between-method CV was 22.9 % (±12.9 %). However, after harmonization by BA-BHA, both weighted Deming and Passing-Bablok regressions equations presented harmonized results. Mean differences were −0.3 to 0.2 % and differences at specific levels were −1.1 to 1.6 %. LoAs were −23.3 to 23.2 %. Between-method CV was 8.4 % (±4.0 %). The data points were evenly distributed at both sides of the mean in Bland-Altman plots.

Conclusions

The inequivalence of test results between different methods can be improved but unacceptable analytical differences at specific levels may be hidden in terms of an acceptable slope and intercept on WD-BHA. The new protocol BA-BHA may be a viable alternative to optimize the harmonization for immunoassays.
Assessment of anti-diabetic properties of Ziziphus oenopolia (L.) wild edible fruit extract: In vitro and in silico investigations through molecular docking analysis
Authors: Vadivu R. Shunmuga , Bakthavatchalam Senthil , Rani Vasthi Gnana , Hirad Abdurahman Hajinur , Wen Zhi-Hong , Yuan Chien-Han , Vinayagam Ramachandran
Published: May 2024

Globally, healthcare is concerned about the rising prevalence of type 2 diabetes. Phytochemicals from medicinal plants have shown great promise in improving human health. The present study aimed to determine the secondary metabolites of Ziziphus oenopolia (L.) fruit extract that contribute to its anti-diabetic activity. The anti-diabetic properties were assessed by in vitro and in silico approaches using α-amylase and α-glucosidase inhibitory assays. Gas chromatography and mass spectroscopy analyses were used to profile Z. oenopolia fruit contents, and a total of four bioactive chemicals and eight phytocompounds were tentatively identified, including flavonoids, terpenoids, phenols, steroids, tannins, and saponins. The Z. oenopolia fruit hydroalcoholic extract inhibits α-amylase and α-glucosidase enzymes in a dose-dependent manner (IC50 = 328.76 and 337.28 µg/mL, R
2 = 0.979 and 0.981). Additionally, phytochemicals found in Z. oenopolia fruit exhibit the ability to inhibit anti-diabetic targets, specifically α-amylase and α-glucosidase (2QV4 vs 3A4A; correlation coefficient, r = 0.955), as demonstrated by computational analysis. This establishes the fruit as a promising and environmentally friendly option for treating hyperglycemia, highlighting the positive correlation between anti-diabetic objectives.
On a generalization of the Opial inequality
Authors: Bosch Paul , Portilla Ana , Rodriguez Jose M. , Sigarreta Jose M.
Published: May 2024

Inequalities are essential in pure and applied mathematics. In particular, Opial’s inequality and its generalizations have been playing an important role in the study of the existence and uniqueness of initial and boundary value problems. In this work, some new Opial-type inequalities are given and applied to generalized Riemann-Liouville-type integral operators.
On Periodic solutions for implicit nonlinear Caputo tempered fractional differential problems
Authors: Bouriah Soufyane , Salim Abdelkrim , Benchohra Mouffak , Karapinar Erdal
Published: May 2024

The main goal of this article is to study the existence and uniqueness of periodic solutions for the implicit problem with nonlinear fractional differential equation involving the Caputo tempered fractional derivative. The proofs are based upon the coincidence degree theory of Mawhin. To show the efficiency of the stated result, two illustrative examples will be demonstrated.
CYP2D6 inhibition by diphenhydramine leading to fatal hydrocodone overdose
Authors: Whitt Aaron G. , Jortani Saeed A.
Published: May 2024

Objectives

Fatal drug overdoses often involve multiple co-intoxicants, including opioids. Hydrocodone, the most prescribed opioid for pain management, is metabolized to the active metabolite hydromorphone by hepatic CYP2D6. Inhibition of CYP2D6 by other compounds can disrupt the analgesic properties of hydrocodone and extend its half-life. Diphenhydramine is an over-the-counter cold medication and is known to inhibit CYP2D6 activity.

Case presentation

A woman in her late 50s was prescribed hydrocodone/acetaminophen (Norco® 10/325). Days before her death, she began taking diphenhydramine for cold symptoms. A post-mortem toxicology report detected the following compounds by High Performance Liquid Chromatography/Time of Flight-Mass Spectrometry (LC/TOF-MS) analysis: acetaminophen (14 μg/mL), hydrocodone (410 ng/mL), dihydrocodeine (24 ng/mL), and diphenhydramine (150 ng/mL). Hydromorphone was not detected (<2 ng/mL). All compounds were detected in therapeutic concentrations, except for hydrocodone, which was present at lethal concentrations.

Conclusions

This case highlights a fatal drug-drug interaction between hydrocodone and diphenhydramine. The estimated total body burden of hydrocodone was 6- to 12-fold higher than acetaminophen, which is unexpected, as these two drugs were administered as a single formulation and have similar half-lives. Furthermore, hydromorphone was undetectable. Taken together, these findings are highly suggestive of a fatal opioid overdose precipitated by diphenhydramine.
Comparative study on enzyme activity, microstructure, drying kinetics, and physicochemical properties of apple slices affected by microwave and steam blanching
Authors: Fang Kuo , Xu Huihuang , Wu Min
Published: May 2024

The influence of microwave blanching (MWB) at different times (30–120 s) on the physicochemical properties, microstructure, and drying characteristics of apple slices, compared to steam blanching (SB) was investigated. Results showed that MWB resulted in greater weight loss and more efficient enzyme inactivation efficiency than SB. The MWB process facilitated the moisture diffusion, resulting in a significant (p < 0.05) reduction in drying time of up to 27.78 % and specific energy consumption of up to 50.00 %. Microstructural observations confirmed that this result stemmed from the development of microporous channels within the cellular tissue structure. The Page model exhibited a higher applicability to the drying of apple slices. Moreover, MWB was more effective than SB in inhibiting browning and retaining phenolic compounds. However, concerning amino acid retention, the dried samples treated with SB for 30 s (21.36 ± 0.83 mg/g DW) showed superior performance compared to dried samples treated with MWB. In addition, molecular docking results suggested that amino acids could form the distinctive flavor of dried apple slices through hydrogen bonding with taste receptors.
Invariant pseudoparallel submanifold of an SQ-Sasakian manifolds
Authors: Atçeken Mehmet , Mert Tuğba , Uygun Pakize
Published: May 2024

The aim of the present paper is to study invariant pseudoparallel
submanifolds in an SQ-Sasakian manifold with respect to semisymmetric metric
connection. We search the necessary and sufficient conditions for an
invariant submanifold to be totally geodesic under the some hypotheses.
On recovering Sturm–Liouville operators with two delays
Authors: Vojvodić Biljana , Vladičić Vladimir
Published: May 2024

We study the inverse spectral problems of recovering Sturm–Liouville differential operator with two constant delays

a
1

{a_{1}}

and

a
2

{a_{2}}

greater than one third of the interval. It has been proved that the operator can be recovered uniquely from four spectra under the condition

2
⁢

a
1

+

a
2

2

≥
π

{2a_{1}+\frac{a_{2}}{2}\geq\pi}

, while it is not possible otherwise.
Transvaginal three-dimensional ultrasound assessment of embryonic genital tubercle at 8–10+6 weeks of gestation
Authors: Hata Toshiyuki , Kawahara Tomomi , Takayoshi Riko , Miyagi Yasunari , Miyake Takahito
Published: May 2024

Objectives

To assess embryonic genital tubercle using transvaginal three-dimensional (3D) ultrasound at 8–10+6 weeks of gestation.

Methods

One-hundred and two transvaginal 3D ultrasound scans were performed for first-trimester dating at 8–10+6 weeks of gestation. The genital tubercle angle (GTA) and genital tubercle length (GTL) were measured with a mid-sagittal view of the embryo using the 3D ultrasound multiplanar mode. Intra- and inter-observer agreements regarding GTA and GTL were also assessed with Bland–Altman plots and intra- and inter-correlation coefficients.

Results

There were no significant differences in GTA between male and female embryos at 8, 9, 10 weeks, or 8–10+6 weeks of gestation, respectively. There were also no significant differences in GTL between male and female embryos at 8, 9, 10 weeks, or 8–10+6 weeks of gestation, respectively. However, GTL increased linearly with advancing gestation (r=0.8276, p<0.00001). Mean GTL (SD) values at 8, 9, and 10 weeks were 0.833 mm (0.274), 1.623 mm (0.262), and 2.152 mm (0.420), respectively (p<0.001). Intra- and inter-reproducibilities of GTA and GTL were excellent. The intra- and inter-correlation coefficients of GTA and GTL were 0.964 and 0.995, and 0.996 and 0.9933, respectively.

Conclusions

The genital tubercle could be identified using transvaginal 3D ultrasound at 8–10+6 weeks of gestation. However, sex differentiation could not be performed at this age. The genital tubercle linearly developed with advancing gestation during the mid-first trimester of pregnancy.
Dear ChatGPT – can you teach me how to program an app for laboratory medicine?
Authors: Meyer Annika , Ruthard Johannes , Streichert Thomas
Published: May 2024

Objectives

The multifaceted potential of ChatGPT in the medical domain remains underexplored, particularly regarding its application in software development by individuals with a medical background but limited information technology expertise.

Methods

This study investigates ChatGPT’s utility in creating a laboratory medicine application.

Results

Despite minimal programming skills, the authors successfully developed an automated intra-assay, inter-device precision test for immunophenotyping with a shiny user interface, facilitated by ChatGPT. While the coding process was expedited, meticulous oversight and error correction by the authors were imperative.

Conclusions

These findings highlight the value of large language models such as ChatGPT in code-based application development for automating work processes in a medical context. Particularly noteworthy is the facilitation of these tasks for non-technically trained medical professionals and its potential for digital medical education.
Preparation of sulfur nanoparticles in chitosan-copper complex and investigation of its nematicidal activity against Pratylenchus pratensis in vitro
Authors: Du Bui Duy , Nguyen Hong Nhung , Tran Phuoc Tho , Tuan Le Nghiem Anh , Nguyen Quoc Hien , Phan Dinh Tuan
Published: May 2024

Sulfur nanoparticles (SNPs) in chitosan-copper (CS-Cu2+) complex solution were prepared by hydrolysis of sodium thiosulfate (Na2S2O3) in an acidic medium of CS-Cu2+ complex. The size of SNPs was inversely proportional to the Cu2+/−NH2 molar ratio, decreasing from 35 to 22 nm corresponding to the Cu2+/−NH2 molar ratio increasing from 0/1 to 1/1. The SNPs/CS-Cu2+ complex was characterized by Ultraviolet-Visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) spectroscopy. The nematicidal activity against Pratylenchus pratensis in vitro was investigated by treating the CS-Cu2+ complex and SNPs/CS-Cu2+ complex with Cu2+/−NH2 molar ratio of 0.5/1. Results showed that the nematicidal activity of the SNPs/CS-Cu2+ complex was higher than that of the CS-Cu2+ complex, particularly the 50 % lethal dose (LC50) after 48 h of treatment was 77 and 89 mg/L, respectively. The results demonstrated that the prepared SNPs/CS-Cu2+ complex can be used as a nematicide for plants.
Restoration of the Information on De-colourized Architectural Cyanotypes
Authors: Sentoku Sawako , Kida Keiko
Published: May 2024

Cyanotypes are known to de-colourize with alkalis; however, not much research has been done to regain the lost information. This research examines two possibilities to bring back the information: one is to utilize elemental mapping by X-ray fluorescence spectroscopy analysis to regain the image non-invasively, and the second, to treat the cyanotype with acidic solutions. Both methods brought back the image to the extent that the information could be obtained. As photo reproductions, one of their greatest values is the information they convey. This research could be significant in that it opens possibilities to regain the lost information.
Demography, Economy and Policy Choices: The Three Corners of the Pension Conundrum
Authors: De Santis Gustavo
Published: May 2024

NDC (notional defined contribution) pension systems are usually considered the best in the PAYGO (pay-as-you-go) category: they mimic funding, seem to be well balanced, and have very limited distortionary effects on the labour market. In this paper, after highlighting of few of their weaknesses, I suggest an alternative solution to the pension problem: IPAYGO, or improved PAYGO. Its guiding principle, “everything is relative”, is applied consistently to both the economic and the demographic part of the problem: this makes the system viable in all possible demographic and economic scenarios. Depending on a few explicit policy (parametric) choices, IPAYGO may take very different shapes, and adapt to national preferences, such as early or late retirement, generous or limited pension benefits, and greater or lesser emphasis on actuarial equity. A properly designed IPAYGO, even in its basic form (the only one discussed here), can tackle issues such as inequities deriving from differential mortality (with the richer living longer), pension-induced low fertility, and quasi-capital gains and losses. While IPAYGO is conceived to be an operative instrument, it can also be used to evaluate existing pensions systems, and the phase a population is going through, with a novel measure of the so-called “demographic bonus” (or “malus”).
Exploring Ca2+Dynamics in Myelinating Oligodendrocytes through rAAV-Mediated jGCaMP8s Expression in Developing Spinal Cord Organ Cultures
Authors: Pachetti Maria , Palandri Anabela , de Castro Reis Fernanda , Recupero Luca , Ballerini Laura
Published: May 2024

Oligodendrocytes, the myelin-producing glial cells of the central nervous system (CNS), crucially contribute to myelination and circuit function. An increasing amount of evidence suggests that intracellular calcium (Ca2+) dynamics in oligodendrocytes mediates activity-dependent and activity-independent myelination. Unraveling how myelinating oligodendrocytes orchestrate and integrate Ca2+signals, particularly in relation to axonal firing, is crucial for gaining insights into their role in the CNS development and function, both in health and disease. In this framework, we used the recombinant adeno-associated virus/Olig001 capsid variant to express the genetically encoded Ca2+indicator jGCaMP8s, under the control of the myelin basic protein promoter. In our study, this tool exhibits excellent tropism and selectivity for myelinating and mature oligodendrocytes, and it allows monitoring Ca2+activity in myelin-forming cells, both in isolated primary cultures and organotypic spinal cord explants. By live imaging of myelin Ca2+events in oligodendrocytes within organ cultures, we observed a rapid decline in the amplitude and duration of Ca2+events across different in vitro developmental stages. Active myelin sheath remodeling and growth are modulated at the level of myelin–axon interface through Ca2+signaling, and, during early myelination in organ cultures, this phase is finely tuned by the firing of axon action potentials. In the later stages of myelination, Ca2+events in mature oligodendrocytes no longer display such a modulation, underscoring the involvement of complex Ca2+signaling in CNS myelination.
Device simulation and optimization of HTL-free perovskite solar cell with CH3NH3SnBr3 as the absorber layer using solar cell capacitance simulator software
Authors:   Department of Physics ,Sree Narayana College, Nattika,University of Calicut, Kerala, India,PIN-680566, Kavitha M. V. , Anjali C. K. ,   Department of Physics ,Sree Narayana College, Nattika,University of Calicut, Kerala, India,PIN-680566, Sudheer K. S. ,   Opto electronic Device simulation Research Lab, Department of Physics, Christ College (Autonomous), Irinjalakuda, University of Calicut, Kerala, India, PIN680125
Published: May 2024

Perovskite solar cells without a hole transport layer have gained popularity due to their stability and affordable manufacturing cost. In this work, device simulation of the solar cell structure is done using SCAPS-1D software with TiO2 as the Electron Transport Layer while toxic-free compound CH3NH3SnBr3 as the absorber material. The efficiency of the structure is found to be 12.63%. The cell performance parameters are investigated by varying individual cell parameters such as absorber layer thickness, absorber layer defect density and doping concentration, ETL thickness, ETL doping concentration, temperature and defect density of the absorber/ETL interface while holding others constant. Simulation with the optimised cell parameter values improves the efficiency to 24.02%.
Effects of composition on the structure, thermal and some physical characteristics of Bi2O3-B2O3-ZnO-SiO2 glasses
Authors:   Ukrainian State University of Chemical Technology, 8 Gagarin Avenue, Dnipro, 49005, Ukraine, Hordieiev Yu. S. , Zaichuk A. V. ,   Ukrainian State University of Chemical Technology, 8 Gagarin Avenue, Dnipro, 49005, Ukraine
Published: May 2024

The influence of composition on the structure, thermal, and some physical characteristics of bismuth borate glasses, formulated as 55Bi2O3–(35-x-y)B2O3–(5+x)ZnO–(5+y)SiO2 (where 0 ≤ x, y ≤ 15 mol%), was investigated. Comprehensive analyses were conducted using techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Differential Thermal Analysis (DTA), and Dilatometry. XRD confirmed the amorphous nature of the glass samples, while FTIR spectroscopy revealed that the glasses are primarily composed of BO4, BO3, BiO6, BiO3, ZnO4, and SiO4 structural units. DTA provided further evidence of the samples' glassy state and insights into key temperatures like glass transition (Tg), crystallization (Tc), and melting (Tm). The study finds that substituting B2O3 with SiO2 increases all characteristic temperatures, whereas replacing it with ZnO decreases Tg and Tc but increases Tm. The maximum thermal stability, indicated by a ΔT of 99°C, was observed in the glass with a 55Bi2O3–20B2O3–20ZnO–5SiO2 composition. Dilatometric measurements showed that the investigated glasses have a high coefficient of thermal expansion (10.0–10.7 ppm/°C) values, a low glass transition temperature (345–376°C), and a low dilatometric softening temperature (364–392°C). Additionally, the density and molar volume of the samples were accurately determined.
Novel synthesis and spectroscopic analysis of gallium oxide doped zinc phosphate glass
Authors:   School of Chemistry, University of the Punjab, New Campus Lahore 54590, Pakistan, Batool A. , Hussain Z. ,   School of Chemistry, University of the Punjab, New Campus Lahore 54590, Pakistan, Din M. I. ,   School of Chemistry, University of the Punjab, New Campus Lahore 54590, Pakistan
Published: May 2024

Phosphate glasses are known for their wide applications in the field of optical fiber, lasers, seals and sensors. Glass system containing (40-x) ZnO-xGa2O3-50P2O5- Na2O, where x=0 to 10mol % were prepared. The effect of gallium oxide on the properties of these glasses were studied. To observe the structure of prepared phosphate glasses FTIR was used under the wavelength range of 400-4000 cm-1 . The prominent peaks appeared in region 400 cm-1 to 2500 cm-1 . The glasses were transparent up to 1500 cm-1 which make them suitable in the field of lasers. The FTIR also confirmed that Q2 structure dominates these glasses
Teoría de la comprensión de lectura de Isabel Solé (1992): implementación desde el manga
Authors: Figueroa Galvis Laura Michelle
Published: May 2024

El objetivo de este artículo es ofrecer a los lectores los resultados de la investigación centrada en utilizar el manga para fortalecer la comprensión lectora de estudiantes de octavo grado del Instituto Arquidiocesano San Francisco de Asís; Pamplona, Norte de Santander, Colombia. Se designó como marco de inteligibilidad la teoría estrategias de lectura de Isabel Solé. La metodología estuvo apoyada por un enfoque cualitativo y un método de Investigación – Acción. Para recolectar la información se utilizó la entrevista a docentes, que arrojó una baja comprensión y poco interés de los estudiantes al ejercicio lector, ligado a la inadecuada presentación textual. Se utilizó el diario de campo y prueba diagnóstica y de salida. Aplicadas las estrategias de lectura literal e inferencial, se recolectaron aspectos para determinar la estructuración final de la propuesta pedagógica “Ya que no tenemos alas, debemos hallar otra forma de volar” que logró percibir un incremento en el nivel de lectura literal y la construcción de bases para una lectura inferencial.
Las giras educativas como estrategia de sensibilización para el personal docente de la durante las clases virtuales en pandemia
Authors: Ugalde Villalobos María Eugenia
Published: May 2024

The Professional Secretarial School (PSS) of the National University of Costa Rica, before the COVID-19 pandemic, as part of an outreach process, conducted two educational tours to the Tele-secondary school of Lanas de Puriscal, San José, Costa Rica. It is located two hours away from the center of this community, with a difficult road to access due to the dirt and mud, where there is hardly any electricity and even less internet in the students' homes. It is worth noting that two of them are now studying at the PSS. PSS professors conducted educational tours to train the students and teachers of that institution in Spanish, English, and Technology topics. However, due to the pandemic, these tours became a sensitization process for some teachers regarding virtual classes, as they were actual witnesses to the situation experienced by these students. Consequently, it is necessary to evaluate the sensitization the teachers underwent and how it modified their behavior with the students from the area during the pandemic. This essay was developed based on the following question: How did the educational tour influence the teachers' treatment of students in virtual classes during the pandemic?
Lignin Interdiffusion– A Mechanism Behind Improved Wet Strength
Authors:   Mid Sweden University, Joelsson Tove ,   MoRe Research Örnsköldsvik AB, Box 70, SE-89122 Örnsköldsvik, Sweden, Mattsson Amanda ,   Mid Sweden University, Ketoja Jukka A. ,   Mid Sweden University; VTT Technical Research Centre of Finland Ltd, Pettersson Gunilla ,   Mid Sweden University, Engstrand Per ,   Mid Sweden University
Published: May 2024

We have studied ways of improving strength properties of paper made from high yield pulps and lignin-rich chemical pulps by utilizing the thermoplastic properties of the lignin present in the fibre walls. Both dry and wet strength can be improved by hot pressing of sheets made from lignin-rich pulps. In this paper, we focus on aspects of the wet-strength development as a function of lignin content and temperature. Here we apply an activation energy evaluation approach to study lignin intermixing or interdiffusion. By means of hot pressing, it is possible to reach wet strength levels up to 50% of the dry strength level, provided that we use pulps with high enough lignin content. Our study included hot pressing of high yield pulps such as thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), high-temperature chemithermomechanical pulps (HTCTMP), unbleached northern softwood kraft (NSK) and northern bleached softwood kraft (NBSK). The sheet pressing trials were performed for varied temperatures from room temperature up to 270°C. As the activation energy for the high yield pulps and the lignin-rich NSK were all in the range of 20-32 kJ/mol, we suggest that the wet strength development as function of temperature has a similar mechanism as long as the pulp fibres contain enough lignin. We also suggest that the phenomenon involves intermixing and/or interdiffusion of wood polymers between adjacent fibres when they are in a close contact. Most probably both the amorphous wood polymers, i.e. the linear hemicelluloses and the cross-linked lignin, mix with each other across the fibre-fibre or even more probable over the fibril-fibril contact surface. While the hemicellulose can intermix already at room temperature under moist conditions, the lignin intermixes more easily at the higher temperature we use. We do not know how far the hemicellulose or lignin could move within the fibre walls, but it seems that the amount of lignin present on the fibre surfaces plays an important role.
Invited Perspective: Strong or Fluffy Nanopapers: How to Utilise Cellulose Nanofibrils Effectively?
Authors:   Polymer & Composite Engineering (PaCE) Group, Institute of Materials Chemistry, Faculty of Chemistry, University of Vienna, Mautner Andreas , Weiland Kathrin ,   Polymer & Composite Engineering (PaCE) Group, Institute of Materials Chemistry, Faculty of Chemistry, University of Vienna, Bismarck Alexander ,   Polymer & Composite Engineering (PaCE) Group, Institute of Materials Chemistry, Faculty of Chemistry, University of Vienna
Published: May 2024

Apart from its wide application in the paper, textile and biomedical industry, cellulose is now an emerging alternative reinforcement to improve the properties of polymers. Numerous research focuses on the development of renewable nanocomposites. In this context, nanocellulose liberated from plant cell walls or produced by bacterial serves as excellent candidate due to its inherently nano-sized nature, high crystallinity and high Young’s modulus. However, numerous cellulose-reinforced polymer nanocomposites reported in literature often failed to fully exploit the fibril tensile stiffness and strength, estimated to be 114 GPa and >2000 MPa, respectively. Nanofibrils can be compounded directly into polymers as reinforcement or used in paper form to produce laminated paperbased composites.
Quantitative Analysis of the Spreading and Adhesion of Latex Binder within Pigment Coating Layer and its Relation to the End-Use Properties of the Coating Layer
Authors:   Center for Coating Materials and Processing and Department of Agriculture, Forestry and Bioresources, Seoul National University, Lee Jee-Hong , Shin Sang Jin ,   Petrochemicals R&D, Research Park, LG Chem. Limited, Yeu Seung Uk ,   Petrochemicals R&D, Research Park, LG Chem. Limited, Lee Hak Lae ,   Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Sciences, Seoul National University; Research Institute of Agriculture and Life Sciences, Seoul National University; State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences)
Published: May 2024

The spreading and adhesion behavior of latex is a crucial factor in determining the structure and properties of the low-latex-content pigment coating layer. In spite of its importance, there has been a lack of analytical techniques to describe these characteristics in a coating layer. This study presents novel parameters and techniques for quantitative analysis of the spreading and adhesion behavior of latex binder in a coating layer, which is based on cross-section SEM image analysis. A comprehensive series of model coating layers were prepared to achieve varying extents of latex spreading. This was prepared by using latices with different glass transition temperatures and various drying or dry-sintering conditions. Parameters were developed to determine and quantify the different morphological characteristics of latices in the coating layers, which had advantages over qualitative observation from the SEM images. Developed analytical techniques were applied to reveal correlations between structural properties and the coating end-use properties, which contributed to a better understanding of coating structure development. A transitional change in coating structure was observed in the low latex spreading domain and this largely influenced the end-use properties of coating layers such as the mechanical properties and light-scattering efficiency. Micro-roughness of the coating surface and gloss were positively correlated to the spreading extent of the latex. It was notable that despite low levels of coating shrinkage due to the low latex content, the micro-roughness still changed with latex spreading variations. Quantitative analysis of latex spreading and mechanical properties of the coating layer also enabled us to separate the adhesion behavior of latex binder into physical and chemical aspects. This would propose a strategy for paper manufacturers to optimize their coated paper products.
High-Throughput Processing of Nanocelluloses into Biodegradable Barrier Coatings
Authors:   Laboratory of Natural Materials Technology, Åbo Akademi University, Koppolu Rajesh , Toivakka Martti ,   Laboratory of Natural Materials Technology, Åbo Akademi University
Published: May 2024

There is an ever-increasing interest towards utilizing nanocellulose as barrier coatings and films, with many companies moving towards pilot scale production of nanocellulose to be used primarily for barrier coatings. However, high suspension viscosity and yield stress, poor adhesion to substrates, poor moisture sensitivity, and additional drying infrastructure needed for large-scale processing of nanocelluloses are some of the challenges that need to be addressed before commercialization. The current work aims at understanding and addressing the above challenges and to develop high-throughput continuous processes required to convert nanocellulose suspensions into barrier coatings and films. Rheology of different types of nanocelluloses across a wide range of shear rates is evaluated with special attention on the influence of dispersants (carboxymethyl cellulose (CMC) and Sodium polyacrylate (NaPA)) on the suspension processability and coating quality. A slot-die applicator is used to apply nanocellulose suspensions as a thin layer on a paper substrate in a continuous process. For moisture protection, biodegradable polymers and dispersions are applied onto the nanocellulose-coated paper via extrusion or dispersion coating. The resulting multilayer structure is then evaluated for its barrier properties viz., oxygen, water vapor, mineral oils, and grease at different test conditions. CMC addition reduces the yield stress, increases water retention, and slows down structure recovery (post high-shear) for nanocellulose suspensions, and thus has positive influence on coating quality and barrier properties. A new Casson-power-cross model was proposed to explain the viscosity behavior of cellulose nanofibrils (CNFs) across a wide shear-rate region, and Herchel-Bulkley model explains the viscosity behavior of cellulose nanocrystals (CNCs). Water vapor permeance for multilayer coatings remained below the control single-layer moisture-barrier materials, and oxygen permeance values were similar or lower than that of pure nanocellulose films. Glycerol and sorbitol plasticizers further improve oxygen barrier and kaolin addition improves the adhesion at nanocellulose/thermoplastic interface. The results provide insight into understanding the various factors that influence the continuous processing of a wide variety of nanocellulose suspensions into biodegradable barrier coatings and will pave the way for industrial production of sustainable packaging.
Engineering Nanocellulose-based Matrices for 3D Cell Cultures
Authors:   Bioresource Processing Research Institute of Australia (BioPRIA) and Department of Chemical and Biological Engineering, Monash University, Curvello Rodrigo , Raghuwanshi Vikram Singh ,   Bioresource Processing Research Institute of Australia (BioPRIA) and Department of Chemical and Biological Engineering, Monash University, Garnier Gil ,   Bioresource Processing Research Institute of Australia (BioPRIA) and Department of Chemical and Biological Engineering, Monash University
Published: May 2024

Cell and organoids culture in three-dimensions (3D) gel systems is important from a fundamental aspect for understanding the development and behaviour of body organs, and from a practical perspective for producing cells, tissues and even new organs for bio-medical applications. The cell culture requires a supportive network environment, biological or synthetic, which provides the suitable biological systems (proteins and co-factors), mechanical support (flexible morphology) and chemical composition for cells/organoids to grow, spread and migrate. Current naturally extracted matrices like, Matrigel and collagen, are expensive with poorly defined and variable composition; they are not reliable for common practice 3D organoids culture. To overcome issues with the naturally extracted matrices, researchers have been investigating and developing new synthetic and natural polymer gels as alternatives. Cellulose has emerged as an attractive matrix with strong potential for cell and organ culture in 2D and 3D networks. The inherent natural biocompatibility of cellulose fibres including non toxicity, low cost, and their ability to form flexible gels, provide a compelling alternative to the current limited and expensive animal-based matrices. This review focuses on the recent development of cellulose nano fibres (CNF) based gel matrices for 3D cell and organoids culture. The review highlights how functionalisation of CNF optimizes the gel structure, visco-elastic properties and composition for supporting cell growth, interactions, spreading and migration. The state-of-the-art characterisation methods are discussed to monitor CNF stiffness, strength, morphology and composition, and furthermore, cell culture and their stability in the CNF network. The knowledge gained from this review aims at supporting bioengineers in further developing the potential of CNF gels for different 3D organs culture and tissue engineering applications.
Invited Perspective: Modelling and Simulation Applications in Paperboard Packaging
Authors:   Tetra Pak Packaging Solutions AB, Lund Sweden, Tryding Johan
Published: May 2024

Today, simulation tools and digital twin models have taken a central role in product development at Tetra Pak. As a result, improved functionality and quality are secured in developing new packages, filling, and converting machines. First, an overview is presented on the development of paper models, followed by examples of how the paper models are used with simulation tools at Tetra Pak today. Such as the creasing and filling process related to material defects.
Mechanical Response of Paperboard in Rapid Compression – The Rapid ZD-Tester, A Measurement Technique
Authors:   RISE Research Institutes of Sweden, Rydefalk Cecilia ,   Royal Institute of Technology, KTH, Hagman Anton ,   RISE Research Institutes of Sweden, Yang Li ,   RISE Research Institutes of Sweden, Kulachenko Artem ,   Royal Institute of Technology, KTH
Published: May 2024

Paperboard is a common material for packages and other carriers of information. During rotary printing processes, the paperboard is subjected to rapid deformations in the out-of-plane direction as it passes through the nip between the rolls of the printer. Being viscoelastic in nature, the mechanical response of the material to high deformation rates differs from what is measured with conventional testing conducted at slower deformation rates. In this work, a device called the rapid ZD-tester is used to show the response of paperboards subjected to a rapid pressure pulse and compare this to measurements made at lower strain rates in a common universal testing machine. All the tested paperboards show complete recovery within 5 s when being rapidly compressed, while the slower compression to the same pressure leaves a deformation that remains after 5 s. The stiffness response differs between the paperboards, but does not consistently increase or decrease between slow or rapid compressions. The difference in response between slow and rapid compression appears larger for the low-density paperboard in the study. The time scales in the rapid ZD-tester are comparable to those in a printing press, and, therefore, evaluation of the material response of the paperboard measured by this device is relevant in the context of printing applications.
Properties of Cellulose Nanofibril Foam Depending on Wet Foaming Conditions
Authors:   Department of Forest Sciences, College of Agriculture and Life Sciences, Seoul National University, Park Shin Young , Goo Sooim ,   Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Sciences, Seoul National University, Shin Heenae ,   Research Institute of Agriculture and Life Sciences, Seoul National University, Kim Jinseung ,   Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Sciences, Seoul National University, Youn Hye Jung ,   Department of Agriculture, Forestry and Bioresources, Research Institute of Agriculture and Life Sciences, Seoul National University
Published: May 2024

Cellulose nanofibril (CNF) foam, which has advantages of sustainability and biodegradability, has a potential to apply to diverse fields including packaging, thermal insulation, and absorbent. In recent days, the oven drying of Pickering-stabilized CNF wet foam was proposed as an alternate approach to manufacture CNF-based porous foams. To produce CNF foam with uniform structure, the properties of wet foam are very important. In this study, carboxymethylated cellulose nanofibril (CMCNF) was used to prepare CNF foam. The effects of wet foaming conditions such as CMCNF consistency, surfactant amount, and shear rate on the properties of the wet and dry foams were investigated. A low addition level of surfactant led to insufficient generation of bubbles, whereas high levels of surfactant generated unstable wet foam. A proper amount of the surfactant and CMCNF consistency yielded wet foams with excellent stability. CNF wet foam with high stability resulted in CNF foam with uniform pore structure and high compressive strength. The shear rate during wet foam generation also had a significant impact on the foamability of wet foam, which determined the density and the pore size of the oven-dried CNF foam.
Invited Perspective: Fundamentals of Interactions Between Cellulose-Rich Surfaces
Authors:   Department of Fibre and Polymer Technology, Division of Fibre Technology and Wallenberg Wood Science Centre, KTH Royal Institute of Technology, Stockholm, Sweden, Wagberg Lars
Published: May 2024

The molecular mechanisms behind the interactions between fibres in fibrous networks, and their link to paper/network strength, have long been under intense scientific investigations and scientific debate (Wågberg and Annergren 1997, Lindström et al. 2005; Hirn and Schennach 2017) but still there is no unified view on how the strength of fibre/fibre joints and network strength can be linked to different molecular mechanisms (Wohlert et al. 2022). Historically the interaction between cellulose-rich fibre surfaces was ascribed to hydrogen bonding and elaborate models were developed for linking mechanical properties of fibrous networks to the H-bonding between the surfaces (Nissan and Batten Jr 1997). This is however an oversimplification for several reasons. First of all, the H-bonds are very specific, which means that they are short-ranged and not implicitly additive over the material volumes engaged in the contact region between the fibres. Secondly the molecular interactions in the fibre/fibre contact zones are actively participating in the formation of the fibre joints, i.e. in the making of the fibre/fibre joints. The interactions in the wet state will hence affect the dimensions of the wet and dry contact zones and they will also create built-in stresses in the zones of contact in the dried fibre/fibre joint. The dry mechanical properties of the fibrous networks, i.e. the breaking of the joints and the fibres, will then be controlled by the molecular contact zone, the interactions in the contact zone, and also outside the molecular contact zone but within the molecular interactions range, the number of molecular contacts/network volume and the individual fibre strength.
Number of program builds: Another criterium for assessing difficulty of a programming task?
Authors: Dobiáš Václav , Šimandl Václav , Vaníček Jiří
Published: May 2024

The paper discusses an alternative method of assessing the difficulty of pupils’ programming tasks to determine their age appropriateness. Building a program takes the form of its successive iterations. Thus, it is possible to monitor the number of times such a program was built by the solver. The variance of the number of program builds can be considered as a criterion of the difficulty of the task. We seek to verify whether this variance is the greatest in the age group for which the task is most suitable. We created several series of programming tasks and offered them to 87000 pupils from 4th to 13th grade. For each task, we compared the optimal age group determined by the variance of the number of program builds method with the group determined by the correct answer ratio method. A strong correlation was observed in traditional microworlds Karel the Robot and Turtle. A moderate correlation was achieved in the new microworld Movie.