bluuebunny/crossref_metadata_2025 huggingface dataset:
Dysfunctional Inflammation in Cystic Fibrosis Airways: From Mechanisms to Novel Therapeutic Approaches
Authors: Ghigo Alessandra , Prono Giulia , Riccardi Elisa , De Rose Virginia
Published: February 2021

Cystic fibrosis (CF) is an inherited disorder caused by mutations in the gene encoding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein, an ATP-gated chloride channel expressed on the apical surface of airway epithelial cells. CFTR absence/dysfunction results in defective ion transport and subsequent airway surface liquid dehydration that severely compromise the airway microenvironment. Noxious agents and pathogens are entrapped inside the abnormally thick mucus layer and establish a highly inflammatory environment, ultimately leading to lung damage. Since chronic airway inflammation plays a crucial role in CF pathophysiology, several studies have investigated the mechanisms responsible for the altered inflammatory/immune response that, in turn, exacerbates the epithelial dysfunction and infection susceptibility in CF patients. In this review, we address the evidence for a critical role of dysfunctional inflammation in lung damage in CF and discuss current therapeutic approaches targeting this condition, as well as potential new treatments that have been developed recently. Traditional therapeutic strategies have shown several limitations and limited clinical benefits. Therefore, many efforts have been made to develop alternative treatments and novel therapeutic approaches, and recent findings have identified new molecules as potential anti-inflammatory agents that may exert beneficial effects in CF patients. Furthermore, the potential anti-inflammatory properties of CFTR modulators, a class of drugs that directly target the molecular defect of CF, also will be critically reviewed. Finally, we also will discuss the possible impact of SARS-CoV-2 infection on CF patients, with a major focus on the consequences that the viral infection could have on the persistent inflammation in these patients.
A Minimal Theory of Creative Ability
Authors: Stevenson Claire , Baas Matthijs , van der Maas Han
Published: February 2021

Despite decades of extensive research on creativity, the field still combats psychometric problems when measuring individual differences in creative ability and people’s potential to achieve real-world outcomes that are both original and useful. We think these seemingly technical issues have a conceptual origin. We therefore propose a minimal theory of creative ability (MTCA) to create a consistent conceptual theory to guide investigations of individual differences in creative ability. Building on robust theories and findings in creativity and individual differences research, our theory argues that creative ability, at a minimum, must include two facets: intelligence and expertise. So, the MTCA simply claims that whenever we do something creative, we use most of our cognitive abilities combined with relevant expertise to be creative. MTCA has important implications for creativity theory, measurement, and practice. However, the MTCA isn’t necessarily true; it is a minimal theory. We discuss and reject several objections to the MTCA.
Responder Needs Addressed by Arctic Maritime Oil Spill Modeling
Authors: Manning Jessica , Verfaillie Megan , Barker Christopher , Berg Catherine , MacFadyen Amy , Donnellan Michael , Everett Mark , Graham Clifton , Roe Jason , Kinner Nancy
Published: February 2021

There is a greater probability of more frequent and/or larger oil spills in the Arctic region due to increased maritime shipping and natural resource development. Accordingly, there is an increasing need for effective spilled-oil computer modeling to help emergency oil spill response decision makers, especially in waters where sea ice is present. The National Oceanic & Atmospheric Administration (NOAA) Office of Response & Restoration (OR&R) provides scientific support to the U.S. Coast Guard Federal On-Scene Coordinator (FOSC) during oil spill response. OR&R’s modeling products must provide adequate spill trajectory predictions so that response efforts minimize economic, cultural, and ecologic impacts, including those to species, habitats, and food supplies. The Coastal Response Research Center is conducting a project entitled Oil Spill Modeling for Improved Response to Arctic Maritime Spills: The Path Forward, in conjunction with modelers, responders, and researchers. A goal of the project is to prioritize new investments in model and tool development to improve response effectiveness in the Arctic. The project delineated FOSC needs during Arctic maritime spill response and provided a solution communicating sources of uncertainty in model outputs using a Confidence Estimates of Oil Model Inputs and Outputs (CEOMIO) table. The table shows the level of confidence (high, medium, low) in a model’s trajectory prediction over scenario-specific time intervals and the contribution of different component inputs (e.g., temperature, wind, ice) to that result.
Does Structural Color Exist in True Fungi?
Authors: Brodie Juliet , Ingham Colin J. , Vignolini Silvia
Published: February 2021

Structural color occurs by the interaction of light with regular structures and so generates colors by completely different optical mechanisms to dyes and pigments. Structural color is found throughout the tree of life but has not, to date, been reported in the fungi. Here we give an overview of structural color across the tree of life and provide a brief guide aimed at stimulating the search for this phenomenon in fungi.
A Long-Lasting CofP of New and Native Speakers—Practices, Identities of Belonging and Motives for Participation
Authors: Arendt Birte
Published: February 2021

Within sociolinguistic research on small languages like Low German, differentiation into new and native speakers has become established. The relationship between the two different groups of speakers is sometimes conceptualized as an insurmountable “gap”. In addition to different acquisition paths and competencies, identity discourses of belonging, authority and authenticity, as well as typical practices, are all crucial elements of these differences. Despite these differences, the intergenerational language-centered analog community of practice (CofP) “Plattdüütschkring” consisting of approximately 10 new and native speakers of the regional language Low German has existed since 2005. This article is based on an explorative case-study analyzing the network “Plattdüütschkring” as an example of successful cooperation between new speakers and native speakers on the basis of typical attitudes and linguistic practices. In order to gain authentic, subjectively experienced insights into identities, normative conceptions and individual language experiences within and outside the network, meta-linguistic reflections of the members themselves were analyzed. These meta-linguistic reflections were collected through narrative interviews with the same and different members at the two survey dates 2010/11 and 2020. The findings show norms of monolingual language use, narrative identities of a normative hierarchy of acquisition scenarios and competences as aspects of belonging. Social and learning-oriented and thus multiple individually appropriate functions of the network can explain the motivation for long-term membership. These outcomes help to understand the role of language attitudes in CofP in the language development of small languages as well as abstract characteristics of successful language-centered networks.
Multidrug-Resistant Acinetobacter baumannii Genetic Characterization and Spread in Lithuania in 2014, 2016, and 2018
Authors: Kirtikliene Tatjana , Mierauskaitė Aistė , Razmienė Ilona , Kuisiene Nomeda
Published: February 2021

Bacterial resistance to antimicrobial agents plays an important role in the treatment of bacterial infections in healthcare institutions. The spread of multidrug-resistant bacteria can occur during inter- and intra-hospital transmissions among patients and hospital personnel. For this reason, more studies must be conducted to understand how resistance occurs in bacteria and how it moves between hospitals by comparing data from different years and looking out for any patterns that might emerge. Multidrug-resistant (MDR) Acinetobacter spp. was studied at 14 healthcare institutions in Lithuania during 2014, 2016, and 2018 using samples from human bloodstream infections. In total, 194 isolates were collected and identified using MALDI-TOF and VITEK2 analyzers as Acinetobacter baumannii group bacteria. After that, the isolates were analyzed for the presence of different resistance genes (20 genes were analyzed) and characterized by using the Rep-PCR and MLVA (multiple-locus variable-number tandem repeat analysis) genotyping methods. The results of the study showed the relatedness of the different Acinetobacter spp. isolates and a possible circulation of resistance genes or profiles during the different years of the study. This study provides essential information, such as variability and diversity of resistance genes, genetic profiling, and clustering of isolates, to better understand the antimicrobial resistance patterns of Acinetobacter spp. These results can be used to strengthen the control of multidrug-resistant infections in healthcare institutions and to prevent potential outbreaks of this pathogen in the future.
Effect of Paraffin and Silica Matrix Phase Change Materials on Properties of Portland Cement Mortars
Authors: Zetola Vicente , Claros-Marfil Luis J. , Santos Alfonso García , González Fco. Javier Neila
Published: February 2021

In the search for methods to incorporate Phase Change Materials (PCM) into Portland cement mortar mixtures, PCM based on paraffins adhered to a silica-based matrix appear as a suitable option. However, paraffin particles have been observed to escape from the silica matrix when water is added. There are only limited data on how the use of such PCM affects the behaviour of mortars. To evaluate the effect of this PCM addition, Portland mortar mixtures were elaborated with 5%, 10% and 15% of PCM content, and using CEM 42.5 I R and CEM I 52.5 R cement types. Physical properties such as density, open porosity, air content and water absorption were analysed for fresh and dry samples. The results obtained show that the PCM-added mixtures require greater water and cement amounts than the standard mortar mixtures to achieve similar compressive strengths. Compared to non-PCM mixtures the PCM-added mortars present a density lowering of 37% for fresh mixtures and near 45% for dry state forms. A maximum compressive strength of 15.9 MPa was reached for 15% PCM mixtures, while values beyond 40 MPa were achieved for 5% PCM mixtures. Thus, the proposed study contributes to broad the available knowledge of PCM cement mortar mixtures behaviour and their mix design.
Investigation of the Structural Heterogeneity and Corrosion Performance of the Annealed Fe-Based Metallic Glasses
Authors: Liang Dandan , Tseng Jo-Chi , Liu Xiaodi , Cai Yuanfei , Xu Gang , Shen Jun
Published: February 2021

This study investigated the structural heterogeneity, mechanical property, electrochemical behavior, and passive film characteristics of Fe–Cr–Mo–W–C–B–Y metallic glasses (MGs), which were modified through annealing at different temperatures. Results showed that annealing MGs below the glass transition temperature enhanced corrosion resistance in HCl solution owing to a highly protective passive film formed, originating from the decreased free volume and the shrinkage of the first coordination shell, which was found by pair distribution function analysis. In contrast, the enlarged first coordination shell and nanoscale crystal-like clusters were identified for MGs annealed in the supercooled liquid region, which led to a destabilized passive film and thereby deteriorated corrosion resistance. This finding reveals the crucial role of structural heterogeneity in tuning the corrosion performance of MGs.
Polyurethane Foams for Domestic Sewage Treatment
Authors: Dacewicz Ewa , Grzybowska-Pietras Joanna
Published: February 2021

The aim of the study was to assess the possibility of using polyurethane foams (PUF) as a filling of a foam-sand filter to directly treat domestic sewage with increased content of ammonium nitrogen and low organic carbon to nitrogen ratio (C/N). The study compared performance of two types of flexible foams: new, cylinder-shaped material (Novel Foams, NF) and waste, scrap foams (Waste Foams, WF). The foams serving as a filling of two segments of a foam-sand filter were assessed for their hydrophobic and physical properties and were tested for their cell structure, i.e., cell diameter, cell size distribution, porosity, and specific surface area. The study accounted also for selected application-related properties, such as hydrophobicity, water absorption, apparent density, dimensional stability, amount of adsorbed biomass, and the possibility of regeneration. Cell morphology was compared in reference foams, foams after 14 months of the filter operation, and regenerated foams. The experimental outcomes indicated WF as an innovative type of biomass carrier for treating domestic sewage with low C/N ratio. SEM images showed that immobilization of microorganisms in NF and WF matrices involved the formation of multi-cellular structures attached to the inner surface of the polyurethane and attachment of single bacterial cells to the foam surface. The amount of adsorbed biomass confirmed that the foam-sand filter made up of two upper layers of waste foams (with diameters and pore content of 0.50–1.53 mm and 53.0–63.5% respectively) provided highly favorable conditions for the development of active microorganisms.
Public Knowledge, Attitudes, and Practice towards COVID-19 Pandemic in Saudi Arabia: A Web-Based Cross-Sectional Survey
Authors: Alnasser Ali Hassan A. , Al-Tawfiq Jaffar A. , Al-Kalif Mohammed Sheker H. , Shahadah Rubayyi Faris B. , Almuqati Khawlah Saad A. , Al-Sulaiman Bashayer Sulaiman A. , Alharbi Khulud Khalid S. , Alabbad Fatimah Yousef M. , Alabbad Jamilah Yousf M. , Alquwaiz Ibrahim Abdulrahman I. , Almashama Ibrahim Khalil I.
Published: February 2021

(1) Background: COVID-19 has become a worldwide public health problem. No previous study has investigated factors associated with COVID-19 knowledge, attitude, and practice (KAP) after completely lifting the curfew in all Saudi Arabia regions and cities. Therefore, adequate knowledge, a positive attitude, and correct control of COVID-19 are essential to eradicate the disease. Hence, this study aims to assess factors associated with KAP of COVID-19; (2) Methods: This cross-sectional web-based survey was performed with the participation of 4305 individuals aged over 15 years living in Saudi Arabia from 11 to 19 August 2020. They were included using the snowball sampling method; (3) Results: Of the 4305 participants, 94.9% were Saudis, 60% females, and 45.4% were in the age group of 20–34 years, 61.7% married, and 49.3% from the Eastern Province of Saudi Arabia. Most of the participants demonstrated good KAP levels (89.6%, 87.2%, and 87.2%) towards the COVID-19 pandemic, respectively. In addition, most of the participants (85.8%) used the internet and social media as a source for COVID-19 information (4) Conclusions: The finding showed that most of the participants demonstrated good knowledge of COVID-19, positive attitudes, and demonstrated good practices for preventing the spread of disease infection.
A Multi-Mode Broadband Vibration Energy Harvester Composed of Symmetrically Distributed U-Shaped Cantilever Beams
Authors: Huang Xiaohua , Zhang Cheng , Dai Keren
Published: February 2021

Using the piezoelectric effect to harvest energy from surrounding vibrations is a promising alternative solution for powering small electronic devices such as wireless sensors and portable devices. A conventional piezoelectric energy harvester (PEH) can only efficiently collect energy within a small range around the resonance frequency. To realize broadband vibration energy harvesting, the idea of multiple-degrees-of-freedom (DOF) PEH to realize multiple resonant frequencies within a certain range has been recently proposed and some preliminary research has validated its feasibility. Therefore, this paper proposed a multi-DOF wideband PEH based on the frequency interval shortening mechanism to realize five resonance frequencies close enough to each other. The PEH consists of five tip masses, two U-shaped cantilever beams and a straight beam, and tuning of the resonance frequencies is realized by specific parameter design. The electrical characteristics of the PEH are analyzed by simulation and experiment, validating that the PEH can effectively expand the operating bandwidth and collect vibration energy in the low frequency. Experimental results show that the PEH has five low-frequency resonant frequencies, which are 13, 15, 18, 21 and 24 Hz; under the action of 0.5 g acceleration, the maximum output power is 52.2, 49.4, 61.3, 39.2 and 32.1 μW, respectively. In view of the difference between the simulation and the experimental results, this paper conducted an error analysis and revealed that the material parameters and parasitic capacitance are important factors that affect the simulation results. Based on the analysis, the simulation is improved for better agreement with experiments.
Fractional Charge States in the Magneto-Photoluminescence Spectra of Single-Electron InP/GaInP2 Quantum Dots
Authors: Mintairov Alexander , Lebedev Dmitrii , Vlasov Alexei , Bogdanov Andrey , Ramezanpour Shahab , Blundell Steven
Published: February 2021

We used photoluminescence spectra of single electron quasi-two-dimensional InP/GaInP2 islands having Wigner-Seitz radius ~4 to measure the magnetic-field dispersion of the lowest s, p, and d single-particle states in the range 0–10 T. The measured dispersion revealed up to a nine-fold reduction of the cyclotron frequency, indicating the formation of nano-superconducting anyon or magneto-electron (em) states, in which the corresponding number of magnetic-flux-quanta vortexes and fractional charge were self-generated. We observed a linear increase in the number of vortexes versus the island size, which corresponded to a critical vortex radius equal to the Bohr radius and closed-packed topological vortex arrangements. Our observation explains the microscopic mechanism of vortex attachment in composite fermion theory of the fractional quantum Hall effect, allows its description in terms of self-localization of ems and represents progress towards the goal of engineering anyon properties for fault-tolerant topological quantum gates.
Variation of Signal Reflection on Electrodes of Silicon Mach-Zehnder Modulators: Influence of Nanoscale Variation and Mitigation Strategies
Authors: Zeng Zhaobang , Ding Ding , Gao Qianyi , Yang Nan , Zhao Peiyan , Jiang Wei
Published: February 2021

Driving signal reflection on traveling wave electrodes (TWEs) is a critical issue in Mach–Zehnder modulators. Fabrication variation often causes a random variation in the electrode impedance and the signal reflection, which induces modulation characteristics variation. The variation of reflection could be intertwined with the variation of other electrode characteristics, such as microwave signal attenuation, resulting in complexity. Here, we characterize the (partial) correlation coefficients between the reflection and modulation characteristics at different bit rates. Decreasing correlation at higher bit rates is observed. Device physics analysis shows how the observed variation can be related to nanoscale variation of material properties, particularly in the embedded diode responsible for electro-optic modulation. We develop a detailed theory to analyze two variation modes of the diode (P-i-N diode or overlapping P/N regions), which reveal insight beyond simplistic diode models. Microwave signal attenuation tends to reduce the correlation with on-electrode reflection, particularly at high bit rates. The theory shows the relative importance of conductor-induced attenuation and “dielectric”-induced attenuation, with different dependence on the frequency and fabrication variation. Strategies on how to mitigate the effect of variation for better fabrication tolerance are discussed by considering three key factors: pre-shift in structural design, bias condition, and fabrication control accuracy.
Covid-19 and College Students: Food Security Status before and after the Onset of a Pandemic
Authors: Mialki Kaley , House Lisa A. , Mathews Anne E. , Shelnutt Karla P.
Published: February 2021

While the Covid-19 pandemic has increased the number of food insecure households in the United States (US), it is unclear how it has affected college student food security status. College students are ineligible for many Covid-19-related economic relief programs and may find it even more difficult to cope during the pandemic. Therefore, the purpose of this study was to identify and describe the prevalence of food insecurity at a public university before and after the onset of Covid-19 as well as factors associated with any change in food security. Researchers administered a cross-sectional, non-probability survey to college students (n = 3206) that assessed food security status prior to and after the onset of the Covid-19 pandemic, as well as questions related to various sociodemographic characteristics. Data were analyzed using descriptive statistics. Thirty-eight percent of students experienced a change in food security as a result of the pandemic, with 59.6% becoming less food secure, and 40.4% becoming more food secure. Characteristics that were associated with changes in food security included changes in housing and employment status as a result of the pandemic. These findings suggest that the pandemic led to changes in food security among college students, and that economic relief efforts should include college students, who are disproportionately affected by food insecurity.
Natural Bioactive Compounds Useful in Clinical Management of Metabolic Syndrome
Authors: Noce Annalisa , Di Lauro Manuela , Di Daniele Francesca , Pietroboni Zaitseva Anna , Marrone Giulia , Borboni Patrizia , Di Daniele Nicola
Published: February 2021

Metabolic syndrome (MetS) is a clinical manifestation characterized by a plethora of comorbidities, including hyperglycemia, abdominal obesity, arterial hypertension, and dyslipidemia. All MetS comorbidities participate to induce a low-grade inflammation state and oxidative stress, typical of this syndrome. MetS is related to an increased risk of cardiovascular diseases and early death, with an important impact on health-care costs. For its clinic management a poly-pharmaceutical therapy is often required, but this can cause side effects and reduce the patient’s compliance. For this reason, finding a valid and alternative therapeutic strategy, natural and free of side effects, could represent a useful tool in the fight the MetS. In this context, the use of functional foods, and the assumption of natural bioactive compounds (NBCs), could exert beneficial effects on body weight, blood pressure and glucose metabolism control, on endothelial damage, on the improvement of lipid profile, on the inflammatory state, and on oxidative stress. This review focuses on the possible beneficial role of NBCs in the prevention and in the clinical management of MetS and its comorbidities.
Protein Intake and Physical Activity in Newly Diagnosed Patients with Acute Coronary Syndrome: A 5-Year Longitudinal Study
Authors: Greco Andrea , Brugnera Agostino , Adorni Roberta , D’Addario Marco , Fattirolli Francesco , Franzelli Cristina , Giannattasio Cristina , Maloberti Alessandro , Zanatta Francesco , Steca Patrizia
Published: February 2021

Cardiovascular disease is one of the most common causes of hospitalization and is associated with high morbidity and mortality rates. Among the most important modifiable and well-known risk factors are an unhealthy diet and sedentary lifestyle. Nevertheless, adherence to healthy lifestyle regimes is poor. The present study examined longitudinal trajectories (pre-event, 6-, 12-, 24-, 36-, and 60-month follow-ups) of protein intake (fish, legumes, red/processed meat) and physical activity in 275 newly-diagnosed patients with acute coronary syndrome. Hierarchical Generalized Linear Models were performed, controlling for demographic and clinical variables, the season in which each assessment was made, and the presence of anxiety and depressive symptoms. Significant changes in protein intake and physical activity were found from pre-event to the six-month follow-up, suggesting the adoption of healthier behaviors. However, soon after the six-month follow-up, patients experienced significant declines in their healthy behaviors. Both physical activity and red/processed meat intake were modulated by the season in which the assessments took place and by anxiety symptoms over time. The negative long-term trajectory of healthy behaviors suggests that tailored interventions are needed that sustain patients’ capabilities to self-regulate their behaviors over time and consider patient preference in function of season.
Insights into the Bead Fusion Mechanism of Expanded Polybutylene Terephthalate (E-PBT)
Authors: Kuhnigk Justus , Raps Daniel , Standau Tobias , Luik Marius , Altstädt Volker , Ruckdäschel Holger
Published: February 2021

Expandable polystyrene (EPS) and expanded polypropylene (EPP) dominate the bead foam market. As the low thermal performance of EPS and EPP limits application at elevated temperatures novel solutions such as expanded polybutylene terephthalate (E-PBT) are gaining importance. To produce parts, individual beads are typically molded by hot steam. While molding of EPP is well-understood and related to two distinct melting temperatures, the mechanisms of E-PBT are different. E-PBT shows only one melting peak and can surprisingly only be molded when adding chain extender (CE). This publication therefore aims to understand the impact of thermal properties of E-PBT on its molding behavior. Detailed differential scanning calorimetry was performed on neat and chain extended E-PBT. The crystallinity of the outer layer and center of the bead was similar. Thus, a former hypothesis that a completely amorphous bead layer enables molding, was discarded. However, the incorporation of CE remarkably reduces the crystallization and re-crystallization rate. As a consequence, the time available for interdiffusion of chains across neighboring beads increases and facilitates crystallization across the bead interface. For E-PBT bead foams, it is concluded that sufficient time for polymer interdiffusion during molding is crucial and requires adjusted crystallization kinetics.
Effects of Heating and Cooling of Injection Mold Cavity Surface and Melt Flow Control on Properties of Carbon Fiber Reinforced Semi-Aromatic Polyamide Molded Products
Authors: Murata Yasuhiko , Kanno Ryota
Published: February 2021

Fiber reinforced thermoplastics (FRTP), reinforced with glass or carbon fibers, are used to improve the mechanical strength of injection-molded products. However, FRTP has problems such as the formation of weld lines, the deterioration of appearance due to the exposure of fibers on the molded product surface, and the deterioration of the strength of molded products due to the fiber orientation in the molded products. We have designed and fabricated an injection mold capable of melt flow control and induction heating and cooling. This mold can both heat and cool the injection mold. It can also control the melt flow direction using a movable core pin. In this study, the above-mentioned mold was used for the molding of carbon fiber reinforced semi-aromatic polyamide. As a result, we found that increasing the heating temperature of the mold and increasing melt flow control volume contribute to the prevention of the generation of a weld line and the exposure of fibers on the molded product surface, as well as to the formation of a flat surface and increased bending strength. The relationships of these results with the carbon fiber orientation in the molded products and the crystallization of semi-aromatic polyamide were also examined in this study.
False Morphology of Aerogels Caused by Gold Coating for SEM Imaging
Authors: Juhász Laura , Moldován Krisztián , Gurikov Pavel , Liebner Falk , Fábián István , Kalmár József , Cserháti Csaba
Published: February 2021

The imaging of non-conducting materials by scanning electron microscopy (SEM) is most often performed after depositing few nanometers thick conductive layers on the samples. It is shown in this work, that even a 5 nm thick sputtered gold layer can dramatically alter the morphology and the surface structure of many different types of aerogels. Silica, polyimide, polyamide, calcium-alginate and cellulose aerogels were imaged in their pristine forms and after gold sputtering utilizing low voltage scanning electron microscopy (LVSEM) in order to reduce charging effects. The morphological features seen in the SEM images of the pristine samples are in excellent agreement with the structural parameters of the aerogels measured by nitrogen adsorption-desorption porosimetry. In contrast, the morphologies of the sputter coated samples are significantly distorted and feature nanostructured gold. These findings point out that extra care should be taken in order to ensure that gold sputtering does not cause morphological artifacts. Otherwise, the application of low voltage scanning electron microscopy even yields high resolution images of pristine non-conducting aerogels.
On the Development of All-Cellulose Capsules by Vesicle-Templated Layer-by-Layer Assembly
Authors: Eivazi Alireza , Medronho Bruno , Lindman Björn , Norgren Magnus
Published: February 2021

Polymeric multilayer capsules formed by the Layer-by-Layer (LbL) technique are interesting candidates for the purposes of storage, encapsulation, and release of drugs and biomolecules for pharmaceutical and biomedical applications. In the current study, cellulose-based core-shell particles were developed via the LbL technique alternating two cellulose derivatives, anionic carboxymethylcellulose (CMC), and cationic quaternized hydroxyethylcellulose ethoxylate (QHECE), onto a cationic vesicular template made of didodecyldimethylammonium bromide (DDAB). The obtained capsules were characterized by dynamic light scattering (DLS), ζ potential measurements, and high-resolution scanning electron microscopy (HR-SEM). DLS measurements reveal that the size of the particles can be tuned from a hundred nanometers with a low polydispersity index (deposition of 2 layers) up to micrometer scale (deposition of 6 layers). Upon the deposition of each cellulose derivative, the particle charge is reversed, and pH is observed to considerably affect the process thus demonstrating the electrostatic driving force for LbL deposition. The HR-SEM characterization suggests that the shape of the core-shell particles formed is reminiscent of the spherical vesicle template. The development of biobased nano- and micro-containers by the alternating deposition of oppositely charged cellulose derivatives onto a vesicle template offers several advantages, such as simplicity, reproducibility, biocompatibility, low-cost, mild reaction conditions, and high controllability over particle size and composition of the shell.
Correlation of a Temperate UV-Weathering Cycle to Outdoor Exposure for the Determination of the Environmental Instability of Polyethylene Films Using HT-GPC Analysis
Authors: Hill Gavin , Moreira Celine , Huynh Florence , Trufasila Ana , Ly Faith , Lloyd Richard , Sawal Hasan , Wallis Christopher J.
Published: February 2021

Accelerated UV-weathering cycles are predominately used for evaluating the durability of plastic materials, particularly polyethylene (PE) films. The point of failure for this testing is usually the loss of a physical property, such as the loss of tensile strength over time. For plastics designed to be instable under environmental conditions, the accelerated weathering cycles are yet to be defined and their correlation to outdoor exposure has yet to be made. This study demonstrates the utility of a newly defined temperate accelerated UV-weathering cycle, recently codified in the British Standard PAS 9017:2020. In addition, the effectiveness of the laboratory weathering cycle has been correlated to real-world outdoor exposure through simultaneous testing of the same samples at a specialist outdoor exposure site in Florida. The utility of the testing methodology and the performance of the polyethylene samples was demonstrated through the use of High Temperature Gel Permeation Chromatography (HT-GPC) analysis. The data led to a detailed insight into the physico-chemical changes occurring in the PE films upon exposure to environmental stimuli. By comparison, and surprisingly, the techniques employed appear to provide an insight into the processes in which secondary micro-particles of PE are formed from macro-polyethylene samples. The temperate accelerated UV-weathering cycle over 14 days demonstrated an approximate correlation to 90 days of outdoor exposure in Florida for the PE film studied.
Biopolymer Composites as an Alternative to Materials for the Production of Ecological Packaging
Authors: Prochon Miroslawa , Dzeikala Oleksandra
Published: February 2021

The problem of plastic waste has long been a concern for governments and society. However, huge amounts of plastic are still being released into the oceans and the environment. One possible solution is to replace plastics with materials that are more both biodecomposable and biodegradable. The most environmentally friendly materials are made of natural ingredients found in nature, although not all of them can be called biodegradable. In this study, we set out to create a new composite with functional properties that could replace commonly used disposable packaging. To ensure the competitiveness of our solution, we used inexpensive and readily available components, such as gelatin G HOOCCH2CH2C(R1)NHCOCH2NH2 (where R1 is a continuation of the peptide chain), polyvinyl alcohol PVA CH2CH(OH), and glycerin G HOCH2CH(CH2OH)O. The ingredients used in the research come from natural sources; however, they are chemically processed. Some of them, such as polyvinyl alcohol, for example, are biodegradable. With the appropriate selection of the components, in the casting process, the intermixed components made it possible to produce materials that were characterized by good physicochemical properties, including thermal stability, optical transmission of UV-Vis light, cross-linking density, and mechanical strength. The most favorable parameters of thermal stability were observed in casein-containing gelatine forms. The best cross-linking density was obtained in the case of gelatin–glycerine systems. Composite containing caseins distinguished by the highest resistance to flammability, increased thermal stability, flexibility, and greater hardness compared to other composites.
Multi-Objective Optimizations of Non-Isothermal Simulated Moving Bed Reactor: Parametric Analyses
Authors: Wang Jian , Chen Wenwei , Li Yan , Xu Jin , Yu Weifang , Ray Ajay K.
Published: February 2021

Simulated moving bed reactor (SMBR), a multicolumn multifunctional integrated reactor system, which can be exploited with on-site adsorptive separation to enhance conversion of equilibrium-limited reversible chemical reaction. In this article, for generality, a dimensionless SMBR model was developed and effects of five representative temperature distributions among different zones on the performance of an SMBR for reversible reaction in the general form of a reactant decomposed to two products were evaluated based on simultaneous maximization of unit throughput and product purity. Multipliers were applied to adjust some of the model parameters such that different operation modes can be compared under various conditions in the parametric space. The multiobjective optimization problems were solved using the non-dominated sorting genetic algorithm. All simulations were carried out using FORTRAN codes. The results showed that both kinetics and adsorptive separation play important roles in SMBR. When kinetics is fast or adsorptive potency of the reactant is higher than the desired product (B) but lower than byproduct (C), non-isothermal operation can significantly improve unit throughput. On the contrary, feed concentration and reaction enthalpy have minor effects on the optimal solutions. Decision variables based on flow rate ratios and internal concentration profiles were used to explain the trends of Pareto optimal solution.
Endmember Estimation with Maximum Distance Analysis
Authors: Tao Xuanwen , Paoletti Mercedes E. , Haut Juan M. , Ren Peng , Plaza Javier , Plaza Antonio
Published: February 2021

Endmember estimation plays a key role in hyperspectral image unmixing, often requiring an estimation of the number of endmembers and extracting endmembers. However, most of the existing extraction algorithms require prior knowledge regarding the number of endmembers, being a critical process during unmixing. To bridge this, a new maximum distance analysis (MDA) method is proposed that simultaneously estimates the number and spectral signatures of endmembers without any prior information on the experimental data containing pure pixel spectral signatures and no noise, being based on the assumption that endmembers form a simplex with the greatest volume over all pixel combinations. The simplex includes the farthest pixel point from the coordinate origin in the spectral space, which implies that: (1) the farthest pixel point from any other pixel point must be an endmember, (2) the farthest pixel point from any line must be an endmember, and (3) the farthest pixel point from any plane (or affine hull) must be an endmember. Under this scenario, the farthest pixel point from the coordinate origin is the first endmember, being used to create the aforementioned point, line, plane, and affine hull. The remaining endmembers are extracted by repetitively searching for the pixel points that satisfy the above three assumptions. In addition to behaving as an endmember estimation algorithm by itself, the MDA method can co-operate with existing endmember extraction techniques without the pure pixel assumption via generalizing them into more effective schemes. The conducted experiments validate the effectiveness and efficiency of our method on synthetic and real data.
Detection of Specific Building in Remote Sensing Images Using a Novel YOLO-S-CIOU Model. Case: Gas Station Identification
Authors: Gao Jinfeng , Chen Yu , Wei Yongming , Li Jiannan
Published: February 2021

The specific building is of great significance in smart city planning, management practices, or even military use. However, traditional classification or target identification methods are difficult to distinguish different type of buildings from remote sensing images, because the characteristics of the environmental landscape around the buildings (like the pixels of the road and parking area) are complex, and it is difficult to define them with simple rules. Convolution neural networks (CNNs) have a strong capacity to mine information from the spatial context and have been used in many tasks of image processing. Here, we developed a novel CNN model named YOLO-S-CIOU, which was improved based on YOLOv3 for specific building detection in two aspects: (1) module Darknet53 in YOLOv3 was replaced with SRXnet (constructed by superimposing multiple SE-ResNeXt) to significantly improve the feature learning ability of YOLO-S-CIOU while maintaining the similar complexity as YOLOv3; (2) Complete-IoU Loss (CIoU Loss) was used to obtain a better regression for the bounding box. We took the gas station as an example. The experimental results on the self-made gas station dataset (GS dataset) showed YOLO-S-CIOU achieved an average precision (AP) of 97.62%, an F1 score of 97.50%, and had 59,065,366 parameters. Compared with YOLOv3, YOLO-S-CIOU reduced the parameters’ number by 2,510,977 (about 4%) and improved the AP by 2.23% and the F1 score by 0.5%. Moreover, in gas stations detection in Tumshuk City and Yanti City, the recall (R) and precision (P) of YOLO-S-CIOU were 50% and 40% higher than those of YOLOv3, respectively. It showed that our proposed network had stronger robustness and higher detection ability in remote sensing image detection of different regions.
Detection of Pathologic Heart Murmurs Using a Piezoelectric Sensor
Authors: Takahashi Kiichi , Ono Kyoichi , Arai Hirokazu , Adachi Hiroyuki , Ito Masato , Kato Akie , Takahashi Tsutomu
Published: February 2021

This study aimed to evaluate the capability of a piezoelectric sensor to detect a heart murmur in patients with congenital heart defects. Heart sounds and murmurs were recorded using a piezoelectric sensor and an electronic stethoscope in healthy neonates (n = 9) and in neonates with systolic murmurs caused by congenital heart defects (n = 9) who were born at a hospital. Signal data were digitally filtered by high-pass filtering, and the envelope of the processed signals was calculated. The amplitudes of systolic murmurs were evaluated using the signal-to-noise ratio and compared between healthy neonates and those with congenital heart defects. In addition, the correlation between the amplitudes of systolic murmurs recorded by the piezoelectric sensor and electronic stethoscope was determined. The amplitudes of systolic murmurs detected by the piezoelectric sensor were significantly higher in neonates with congenital heart defects than in healthy neonates (p < 0.01). Systolic murmurs recorded by the piezoelectric sensor had a strong correlation with those recorded by the electronic stethoscope (ρ = 0.899 and p < 0.01, respectively). The piezoelectric sensor can detect heart murmurs objectively. Mechanical improvement and automatic analysis algorithms are expected to improve recording in the future.
The Formulation of Epidemic Prevention Work of COVID-19 for Colleges and Universities: Priorities and Recommendations
Authors: Hsu Wan-Chi Jackie , Lo Huai-Wei , Yang Chin-Cheng
Published: February 2021

As the Coronavirus disease 2019 (COVID-19) epidemic spreads all over the world, governments of various countries are actively adopting epidemic prevention measures to curb the spread of the disease. However, colleges and universities are one of the most likely places for cluster infections. The main reason is that college students have frequent social activities, and many students come from different countries, which may very likely cause college campuses to be entry points of disease transmission. Therefore, this study proposes a framework of epidemic prevention work, and further explores the importance and priority of epidemic prevention works. First of all, 32 persons in charge of epidemic prevention from various universities in Taiwan were invited to jointly formulate a campus epidemic prevention framework and determined 5 dimensions and 36 epidemic prevention works/measures/criteria. Next, Bayesian best worst method (BWM) was used to generate a set of optimal group criteria weights. This method can not only integrate the opinions of multiple experts, but also effectively reduce the complexity of expert interviews to obtain more reliable results. The results show that the five most important measures for campus epidemic prevention are the establishment of a campus epidemic prevention organization, comprehensive disinfection of the campus environment, maintenance of indoor ventilation, proper isolation of contacts with confirmed cases, and management of immigration regulations for overseas students. This study provides colleges and universities around the world to formulate anti-epidemic measures to effectively reduce the probability of COVID-19 transmission on campuses to protect students’ right to education.
Relationship between Land Property Security and Brazilian Amazon Deforestation in the Mato Grosso State during the Period 2013–2018
Authors: Okida Daniella Tiemi Sasaki , de Carvalho Júnior Osmar Abílio , Ferreira de Carvalho Osmar Luiz , Gomes Roberto Arnaldo Trancoso , Guimarães Renato Fontes
Published: February 2021

This research examines the relations between forest decrease and legal property security in Mato Grosso State, Brazil. The study area encompasses 133,090.4 km2 of the Amazonian biome, belonging to the Brazilian Legal Amazon, located at the arc of deforestation where agriculture and cattle ranching compete with the native vegetation cover. Cadastral monitoring and certification of productive land plots are Brazil’s public policies to implement to tackle these environmental challenges. In this context, we crossed the Land Management System (SIGEF) dataset launched in 2013 from the National Institute for Agrarian Reform and the Amazon Deforestation Monitoring Program (PRODES) dataset from the Brazilian National Institute of Space Research (INPE). The analysis considered the 2013–2018 period with public and private land plots and evaluated the differences in smallholders and large landowners’ deforesting behavior. The results demonstrate that the primacy of certified properties was in private land (94%), with a small portion of the public land (6%). Most properties have <80% forest coverage on certification, corresponding to 85% on private properties and 95% on public properties. This fact is important because environmental legislation in the Amazon region establishes a legal reserve of 80% in forest areas. The results show that the smaller the property, the greater the percentage of proportional deforestation in the certification. In the biennium, considering before and after certification, a proportion of 8% of private properties and 28% of public properties with vegetation cover had deforestation. The results demonstrate the tendency for smaller properties to deforest proportionally more than larger ones. The annual difference series in properties registered in 2015 demonstrates that the highest deforestation occurrence was in the year of certification in private properties and the subsequent year in public properties. The SIGEF system is relatively new, requiring more time to establish a consolidated trend. The combination of property rights and effective compliance with environmental legislation allows the conservation of the forest. However, it is essential to improve inspection. Land ownership inserts the owner into a system of rules to properly use natural resources, constituting a legal instrument to guide human action.
Potential of Pre-Harvest Wastes of Tobacco (Nicotiana tabacum L.) Crops, Grown for Smoke Products, as Source of Bioactive Compounds (Phenols and Flavonoids)
Authors: Sifola Maria Isabella , Carrino Linda , Cozzolino Eugenio , del Piano Luisa , Graziani Giulia , Ritieni Alberto
Published: February 2021

Tobacco cultivation is characterized by high amounts of waste biomasses whose disposal frequently represents a complex and expensive problem. A study was conducted to evaluate thepotential of pre-harvest light air-cured (Burley) and dark fire-cured (Kentucky) tobacco waste biomasses as a source of bioactive compounds (nutraceutical ingredients) such as polyphenols. Pre-harvest waste materials (topping fresh materials and residual stalks at final harvest) were collected to determine dry matter, total polyphenols content (TPC; Folin assay), and DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,20-azino-bis(3-ethylbenzothiazoline-60-sulfonic acid) diammonium salt) antioxidant capacity. Polyphenols quali-quantitative profiles obtained by Orbitrap Q Exactive of both tobacco types were also determined. Total pre-harvest waste biomass amounted to 3956.9 and 1304.4 kg d.w. ha−1 in light air-cured (Burley) and dark fire-cured (Kentucky) tobacco types, respectively. Polyphenols content, expressed as g kg−1 dry weight (d.w.), ranged between 4.6 and 15.7 g kg−1 d.w. and was generally greater in leaves than in stalks. Considering both leaves and stalks, the light air-cured (Burley) tobacco crop yielded 22.1 kg ha−1 of polyphenols, while the dark fire-cured (Kentucky) tobacco yielded 12.0 kg ha−1. DPPH and ABTS were significantly greater in leaves than in stalks waste biomass in both types of tobacco. The most abundant components were quinic and chlorogenic acids, rutin, and luteolin rutinoside.