bluuebunny/crossref_metadata_2025 huggingface dataset:
Built Environment and Physical Activity among Adults in Hong Kong: Role of Public Leisure Facilities and Street Centrality
Authors: Zhang Ting , Huang Bo , Wong Hung , Wong Samuel Yeung-Shan , Chung Roger Yat-Nork
Published: February 2022

Physical inactivity has been identified as the fourth leading risk factor for global mortality, and has been shown to be related to the built environment. To fill the literature gap from a non-Western setting, we examined: (1) the associations between the built environment and physical activity (PA) behaviors, (2) how the association of street centrality with PA is mediated by public leisure facilities, and (3) whether the association of the built environment with PA differs among people with different perceived PA barriers in Hong Kong. Cross-sectional survey data on 1977 adults were used. Exposure to the built environment was assessed in terms of the density of four types of public leisure facilities (gyms, parks, recreational facilities, and sports facilities) and street centrality. Street centrality was a composite index calculated by gathering four related indicators (reach, betweenness, straightness, and intersection density). Covariates, including socio-demographic variables, perceived neighborhood environment, and perceived PA barriers, were considered. Gym density was significantly associated with vigorous physical activity, but the association became non-significant after controlling for covariates. Sports facility density was associated with a greater probability of moderate physical activity (MPA) and was greater in those who had perceived PA barriers. Additionally, sports facilities partially mediated the association of street centrality with MPA, and fully mediated the association of street centrality with prolonged sitting. Higher park density was associated with lower odds of prolonged sitting. It is important for governments to provide more sports facilities and parks to promote active PA, and to reduce sitting time in adults by creating an active built environment.
Anti-Anemic Effect of Antioxidant-Rich Apple Vinegar against Phenylhydrazine-Induced Hemolytic Anemia in Rats
Authors: Ousaaid Driss , Ghouizi Asmae El , Laaroussi Hassan , Bakour Meryem , Mechchate Hamza , Es-safi Imane , Kamaly Omkulthom Al , Saleh Asmaa , Conte Raffaele , Lyoussi Badiaa , El Arabi Ilham
Published: February 2022

This study aims to examine the ability of apple vinegar on phenylhydrazine (PHZ)-induced hemolytic anemia in Wistar rats. In vitro, phenolic and flavonoid content and antioxidant activity were determined. In vivo, phenylhydrazine (10 mg/kg) was injected intravenously into rats for 4 days and then treated with apple vinegar daily by gavage (1 mL/kg) for five weeks. high level of polyphenols and flavonoids (90 ± 1.66 mg GAE/100 mL and 7.29 ± 0.23 mg QE/100 mL, respectively) were found in the apple vinegar which gives it a good ability to scavenge free radicals (TAC = 4.22 ± 0.18 mg AAE/100 mL and DPPH, IC50 = 0.49 ± 0.004 µL/ml). The phytochemical composition of apple vinegar revealed the presence of numerous bioactive compounds including arbutin, apigenin, sinapic, ferulic and trans-ferulic acids. The major antioxidant components in apple vinegar were ferulic and trans-ferulic acids (40% and 43%, respectively). PHZ treatment induced changes in platelets, blood cell count, mean corpuscular volume, hemoglobin concentration and mean capsulated hemoglobin. However, the co-administration of apple vinegar revealed its capacity to ameliorate the changes induced by phenylhydrazine. Therefore, apple vinegar use could have a positive impact on the prevention of hemolytic anemia induced by phenylhydrazine due to the antioxidant properties of its major components.
Industry 4.0 and the Circular Economy: Integration Opportunities Generated by Startups
Authors: Silva Tiago H. H. , Sehnem Simone
Published: February 2022

Background: The purpose of this study is to analyze the adoption and implementation of technologies related to Industry 4.0 and the integration with circular economy (CE) to minimize the effects of resource scarcity in emergency situations. Method: The study was developed in two stages: The first consists of a systematic review of the literature for analytical categorization of the technologies of Industry 4.0 that can be useful for implementation in the circular economy. In the second step, empirical validation was carried out with 45 foodtech startups from the agribusiness value chain, farm to table, reuse, and waste management and disposal segments. Results: The contributions of the study show that: (i) The business models of startups in the food segment are closely aligned with the assumptions of circular economy. (ii) The technologies of industry 4.0 are supporting the implementation of circular economy in foodtech companies. (iii) Digitization, traceability, software as a service, traceability, digital solutions, and shared platforms occupy the leadership in the interface between CE and industry 4.0. (iv) Partnerships are strategic elements in the creation of innovative ecosystems for the success of foodtech startups. Conclusions: We conclude this paper with a diagnosis about companies involved in the foodtech segment in addition to the proposition of a business and sectorial agenda to consolidate the Industry 4.0 technologies in order to promote circular economy.
Physical Properties of an Eco-Sustainable, Form-Stable Phase Change Material Included in Aerial-Lime-Based Mortar Intended for Different Climates
Authors: Sarcinella Antonella , Aguiar José Luís Barroso de , Frigione Mariaenrica
Published: February 2022

The aim of this experimental investigation was to produce a form-stable phase change material (PCM) able to reduce the need for nonrenewable energy resources required for the heating/cooling of buildings located in regions characterized by different climatic conditions. The innovative PCM must also be sustainable and must be produced according to the principles of the circular economy. To achieve such ambitious goals, a form-stable, sustainable PCM was produced through vacuum impregnation. The form-stable PCM was produced starting from a low-toxicity, low-flammability polyethylene glycol of medium molecular weight (PEG 800), which was included in porous stone granules obtained as waste products of the cutting/processing of local (Lecce) stone. The thermal properties and thermal stability of PEG 800 and of its PCM-composite were evaluated by employing differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA). The appropriate parameters to perform the impregnation procedure were identified through rheological and calorimetric analyses. A simple leakage test was performed to assess if the PEG polymer can leak from the stone flakes. Finally, the new PCM was added as an aggregate in aerial-lime-based mortars, and the mortar’s properties were analyzed in fresh (workability) and hardened (flexural and compressive strength and thermal characteristics) states for potential applications, particularly in ancient buildings.
Corrosion Resistance Mechanism of Mica–Graphene/Epoxy Composite Coating in CO2-Cl− System
Authors: Zhu Shi-Dong , Li Yan-Peng , Wang Hong-Wei , Li Jin-Ling , Fu An-Qing , Chen Gang , Ma Dong , Li Xuan-Peng , Cheng Frank
Published: February 2022

The working environment for tubing in oil and gas fields is becoming more and more serious due to the exploration of unconventional oil and gas resources, leading to the increasing need for a protective internal coating to be used in tubing. Therefore, a new mica–graphene/epoxy composite coating with different graphene contents (0.0, 0.2, 0.5, 0.7, and 1.0 wt.%) was prepared to improve the tubing resistance to a corrosive medium, an autoclave was used to simulate the working environment, and an electrochemical workstation assisted by three-electrodes was used to study the electrochemical characteristics of the coating. The results showed that the addition of a certain amount of graphene into the mica/epoxy coating significantly improved the corrosion resistance of the composite coating, and when the graphene content increased, the corrosion resistance of the mica/epoxy coating first increased and then decreased when the corrosion current density of a 35 wt.% 800# mica/epoxy coating with a 0.7 wt.% graphene content was the lowest (7.11 × 10−13 A·cm−2), the corrosion potential was the highest (292 mV), the polarization resistance was the largest (3.463 × 109 Ω·cm2), and the corrosion resistance was improved by 89.3% compared to the coating without graphene. Furthermore, the adhesion of the coating with 0.7 wt.% graphene was also the largest (8.81 MPa, increased by 3.4%) and had the smallest diffusion coefficient (1.566 × 107 cm2·s−1, decreased by 76.1%), and the thermal stability improved by 18.6%. Finally, the corrosion resistance mechanism of the composite coating with different graphene contents at different soaking times was revealed based on the electrochemistry and morphology characteristics other than water absorption and contact angle.
Spectrometric Analysis of the Wear from Metallic and Ceramic Dental Implants following Insertion: An In Vitro Study
Authors: Romanos Georgios E. , Fischer Gerard A. , Rahman Zaid T. , Delgado-Ruiz Rafael
Published: February 2022

Titanium wear is a growing area of interest within dental implantology. This study aimed to investigate titanium and zirconium wear from dental implants at the time of insertion using X-ray-fluorescence spectrometry (XRF) and an in vitro protocol utilizing artificial bovine bone plates. Five groups were analyzed using XRF-spectrometry: groups 1–4 (titanium implants) and group 5 (zirconia implants). The implants were inserted into two bone blocks held together by a vice. The blocks were separated, and the insertion sites were analyzed for titanium (Ti) and zirconium (Zr). Statistical descriptive analyses of Ti and Zr concentrations in the coronal, middle and apical bone interface were performed. A comparative analysis confirmed differences between the implant’s surface stability and Ti accumulation within the insertion sites of the bone block. There was a direct relationship between implant length and the quantity of titanium found on the bone block. The data generally indicates greater quantities of titanium in the coronal thirds of the implants, and less in the apical thirds. The titanium and zirconium found in the bone samples where the group 5 implants were inserted was not of statistical significance when compared to control osteotomies. The results of this study confirm wear from metallic, but not ceramic, dental implants at the time of insertion.
Heat as a Conductivity Factor of Electrically Conductive Yarns Woven into Fabric
Authors: Penava Željko , Penava Diana Šimić , Knezić Željko
Published: February 2022

In recent years, more and more researchers have been focused on electrically conductive textiles that generate heat or transmit electrical signals and energy to embedded electrical components. In this paper, the dissipation of heat due to the flow of electric current at given voltages is investigated, and at the same time it is determined how this heat affects the change in the electrical resistance of the electrically conductive yarn in the immediate surroundings. Three fabric samples were woven in a plain weave with three types of different electrically conductive yarns. Three electrically conductive yarns are woven in parallel in the weft direction and separated from each other by one polyester (PES) yarn due to electrical insulaton. Conductive yarns are electrically connected so that the outer yarns are used for heating by the flow of electric current at a certain constant voltage, and the central yarn is used only to measure changes in electrical resistance. When electrothermally conductive fabrics are subjected to certain voltages over time, experimental results have shown that resistance values increase over a short period of time and then gradually decrease, while the temperature gradually increases and stabilizes over time. Based on the analysis of the obtained results of the ratio between the values of applied voltage and temperature to the electrically conductive yarns, the value of thermal dissipation in conductive yarns can be calculated in advance depending on the applied voltage. Furthermore, the obtained results can be further used in applications where conductive yarns are used as heaters for realistic prediction of the obtained heat.
Optimal Design of an Ultrasound Transducer for Efficient Acousto-Optic Modulation of Terahertz Radiation
Authors: Nikitin Pavel Alekseevich , Gerasimov Vasily Valerievich
Published: February 2022

Acousto-optic (AO) interaction in the terahertz range was investigated with the use of monolithic ultrasound transducers of various widths. Sulfur hexafluoride (SF6) liquefied at a temperature of about 23 °C and a pressure of 25 bar was used as a medium for AO interaction. The angular and frequency bandwidths of effective AO interaction, as well as the diffraction efficiency per 1 W of the driving electric power, were determined. For the first time, a correct comparison of the AO diffraction efficiency in SF6 with the use of ultrasound transducers with different widths was carried out. In the experiments performed, the highest energy efficiency of the AO modulator was achieved with a transducer with a width of 12 mm.
Glass Lightweight Aggregates from Glass Cullet and Mining and Food Industry Carbonate Waste
Authors: Padilla Isabel , López-Delgado Aurora , Romero Maximina
Published: February 2022

Lightweight aggregates are extensively used in construction and other industrial applications due to their technological characteristics. The extraction of natural aggregates results in serious environmental effects. Thus, within the circular economy concept, the valorization of waste through the optimization of materials and product design is encouraged. In this work, glass lightweight aggregates were prepared from mixtures of white glass cullet and carbonate wastes from mining (wastes originating from the extraction, manufacture and marketing of magnesite and its derivatives) and the food industry (eggshell and mussel shell). The effects of different processing parameters, such as the particle size of the base glass, percentage of the blowing additive, shaping method, heating rate, temperature and processing time, were evaluated. The results indicate that the mineralogical composition of the blowing agent and the particle size of the base glass are the two processing parameters with the greatest impact on expansion efficiency. Thus, glass artificial aggregates were obtained with characteristics similar to those of commercial products (density values ranged between 0.3 and 0.8 g/cm3 and mechanical strength between 0.7 and 1.5 MPa) from thermal shock expansion treatments in the temperature range 800–900 °C and with dwell times no longer than 15 min.
Magnetic Enrichment of SARS-CoV-2 Antigen-Binding B Cells for Analysis of Transcriptome and Antibody Repertoire
Authors: Banach Maureen , Harley Isaac T. W. , McCarthy Mary K. , Rester Cody , Stassinopoulos Adonis , Kedl Ross M. , Morrison Thomas E. , Cambier John C.
Published: February 2022

The ongoing COVID-19 pandemic has had devastating health impacts across the globe. The development of effective diagnostics and therapeutics will depend on the understanding of immune responses to natural infection and vaccination to the causative agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While both B-cell immunity and T-cell immunity are generated in SARS-CoV-2-infected and vaccinated individuals, B-cell-secreted antibodies are known to neutralize SARS-CoV-2 virus and protect from the disease. Although interest in characterizing SARS-CoV-2-reactive B cells is great, the low frequency of antigen-binding B cells in human blood limits in-depth cellular profiling. To overcome this obstacle, we developed a magnetic bead-based approach to enrich SARS-CoV-2-reactive B cells prior to transcriptional and antibody repertoire analysis by single-cell RNA sequencing (scRNA-seq). Here, we describe isolation of SARS-CoV-2 antigen-binding B cells from two seropositive donors and comparison to nonspecific B cells from a seronegative donor. We demonstrate that SARS-CoV-2 antigen-binding B cells can be distinguished on the basis of transcriptional profile and antibody repertoire. Furthermore, SARS-CoV-2 antigen-binding B cells exhibit a gene expression pattern indicative of antigen experience and memory status. Combining scRNA-seq methods with magnetic enrichment enables the rapid characterization of SARS-CoV-2 antigen-binding B cells.
Biochemical Characterization and Cold-Adaption Mechanism of a PL-17 Family Alginate Lyase Aly23 from Marine Bacterium Pseudoalteromonas sp. ASY5 and Its Application for Oligosaccharides Production
Authors: Tang Xiang , Jiao Chao , Wei Yi , Zhuang Xiao-Yan , Xiao Qiong , Chen Jun , Chen Fu-Quan , Yang Qiu-Ming , Weng Hui-Fen , Fang Bai-Shan , Zhang Yong-Hui , Xiao An-Feng
Published: February 2022

As an important enzyme involved in the marine carbon cycle, alginate lyase has received extensive attention because of its excellent degradation ability on brown algae, which is widely utilized for alginate oligosaccharide preparation or bioethanol production. In comparison with endo-type alginate lyases (PL-5, PL-7, and PL-18 families), limited studies have focused on PL-17 family alginate lyases, especially for those with special characteristics. In this study, a novel PL-17 family alginate lyase, Aly23, was identified and cloned from the marine bacterium Pseudoalteromonas carrageenovora ASY5. Aly23 exhibited maximum activity at 35 °C and retained 48.93% of its highest activity at 4 °C, representing an excellent cold-adaptation property. Comparative molecular dynamics analysis was implemented to explore the structural basis for the cold-adaptation property of Aly23. Aly23 had a high substrate preference for poly β-D-mannuronate and exhibited both endolytic and exolytic activities; its hydrolysis reaction mainly produced monosaccharides, disaccharides, and trisaccharides. Furthermore, the enzymatic hydrolyzed oligosaccharides displayed good antioxidant activities to reduce ferric and scavenge radicals, such as hydroxyl, ABTS+, and DPPH. Our work demonstrated that Aly23 is a promising cold-adapted biocatalyst for the preparation of natural antioxidants from brown algae.
IgG4-Related Chronic Sinonasal Pseudotumor with Refractory Nasal Bleeding: A Case Report
Authors: Lee Hsu-Lin , Tsai Meng-Ko , Yang Deng-Ho
Published: February 2022

Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibro-inflammatory and idiopathic autoimmune disorder. IgG4-RD can be characterized by the presence of pseudotumors. Inflammatory pseudotumors may involve any part of a human organ. There are few reports of sinus lesions in IgG4-RD. An 82-year-old man has a history of chronic sinusitis for the last several years and no remarkable family history. Two years before disease presentation, the patient experienced intermittent nasal bleeding, stuffy nose, dizziness, and fatigue. Blood test revealed positive (160X) antinuclear antibody with a mixed speckled and nucleolar pattern, IgG level of 1370 mg/dL, and IgG4 level of 99.7 mg/dL. Computed tomography (CT) of the sinus revealed several calcifications in the sphenoid sinus. Surgical findings revealed tumor-like materials. Pathological examination of the soft tissues revealed acute and chronic granulomatous inflammation. Immunohistochemical analysis demonstrated high levels of positive-affinity markers of IgG, IgG4, and CD138 and a IgG4/IgG ratio > 40%. IgG4-RD with pseudotumor was diagnosed. The initial treatment was intravenous methylprednisolone 120 mg daily for three days and oral prednisolone 10 mg twice a day and azathioprine 50 mg daily. The efficacy of the treatment was insufficient, and nasal bleeding did not decrease. Subsequently administered intravenous rituximab 1000 mg monthly for 2 months. Following this treatment, nasal bleeding stopped. CT revealed reduction in nasal mucosal swelling compared with that in a previous scan. This report highlights that in cases with an inflammatory mass mimicking malignancy, IgG4RD should always be considered, and rituximab treatment is recommended upon failure of steroid and azathioprine therapy.
COPD in Firefighters: A Specific Event-Related Condition Rather than a Common Occupational Respiratory Disorder
Authors: Rajnoveanu Armand-Gabriel , Rajnoveanu Ruxandra-Mioara , Motoc Nicoleta Stefania , Postolache Paraschiva , Gusetu Gabriel , Man Milena Adina
Published: February 2022

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. Smoking remains the most important risk factor, but occupational exposures may play an essential role as well. Firefighters are among occupations regularly exposed to a variety of irritative inhalational products, and they may be expected to develop respiratory health problems because of such an occupational exposure. To better understand and characterize this relationship, we performed an extensive search of the scientific literature, and we identified two major research areas: firefighters exposed to wildland fire smoke and firefighters involved in the World Trade Centre disaster-related operations. Most of the studies did not report a significant increase in COPD diagnosis in firefighters. An accelerated rate of decline in lung function was seen, a short time after major exposure events. This is the reason for an increased rate of exacerbations observed in individuals already diagnosed with obstructive respiratory disorders. A limited number of studies not covering these specific circumstances of exposure were found. They reported long-term morbidity and mortality data, and the results are controversial. Major confounding factors for most of the studies were the “healthy worker effect” and the lack of useful data regarding smoking habits. Efforts should be made in the future to better characterize specific biomarkers for the progression of COPD; to establish exposure limits; and to implement preventive strategies like rotation of workers, smoking cessation programs, and long-term monitoring programs for respiratory disorders.
Does Exercise Affect Telomere Length? A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Song Seonghyeok , Lee Eunsang , Kim Hyunjoong
Published: February 2022

Background and objectives: Telomere length is an indicator of biological aging, and it shortens during cell division. A short telomere length is associated with various age-related diseases and mortality. It is suggested that physical activity has a positive effect on the rate of telomere length shortening. Materials and Methods: Related studies, published in electronic databases, were searched with keywords, including exercise, telomere length, and randomized controlled trial. The data were weighted and pooled through a fixed-effect model. Results: Of the total 49 studies searched, 7 studies with 939 participants were considered suitable, and were analyzed qualitatively and quantitatively. Exercise is beneficial to telomere length. Aerobic exercise was effective as the type of exercise (MD, −0.03; 95% CI, −0.04 to −0.01). In addition, exercise for more than 6 months, with a change in lifestyle, is beneficial for telomere length (MD, −0.02; 95% CI, −0.04 to −0.01). Conclusions: The type and duration of exercise for positive improvement in telomere length is aerobic exercise for more than 6 months.
The Impact of COVID-19 on Behavior and Physical and Mental Health of Romanian College Students
Authors: Silișteanu Sînziana Călina , Totan Maria , Antonescu Oana Raluca , Duică Lavinia , Antonescu Elisabeta , Silișteanu Andrei Emanuel
Published: February 2022

Background and Objectives: The COVID-19 pandemic caused by SARS-CoV-2 significantly marked people’s lives with respect to their behavior, and their physical and mental health. Materials and Methods: This is a cross-sectional study that was conducted in 2021 for a period of 5 months. The study sample included 218 students from the College of Physical Education and Sports of the University of Suceava who filled in a questionnaire on mental, physical and behavioral symptoms caused by the COVID-19 pandemic, as well as the Anxiety Assessment Questionnaire (STAI). Results: The responses indicated increased anxiety, physical symptoms, altered behavior, and increased perception of social restrictions. Regression analyses indicated that the levels of anxiety during the COVID-19 outbreak were strongly correlated with cognitive, physical and behavioral symptoms of the students. These were influenced by the living arrangements, location (urban vs. rural), age group and study year. Conclusions: The results show that first-year students did not exhibit significant physical and cognitive symptoms despite reporting anxiety, probably due to their enthusiasm as beginners. The 3rd year students were prone to anxiety and reported cognitive symptoms, possibly due to the prospects of an uncertain future.
End-of-Life Decision-Making in Pediatric and Neonatal Intensive Care Units in Croatia—A Focus Group Study among Nurses and Physicians
Authors: Rubic Filip , Curkovic Marko , Brajkovic Lovorka , Nevajdic Bojana , Novak Milivoj , Filipovic-Grcic Boris , Mestrovic Julije , Lah Tomulic Kristina , Peter Branimir , Borovecki Ana
Published: February 2022

Background and Objectives: Working in pediatric and neonatal intensive care units (ICUs) can be challenging and differs from work in adult ICUs. This study investigated for the first time the perceptions, experiences and challenges that healthcare professionals face when dealing with end-of-life decisions in neonatal intensive care units (NICUs) and pediatric intensive care units (PICUs) in Croatia. Materials and Methods: This qualitative study with focus groups was conducted among physicians and nurses working in NICUs and PICUs in five healthcare institutions (three pediatric intensive care units (PICUs) and five neonatal intensive care units (NICUs)) at the tertiary level of healthcare in the Republic of Croatia, in Zagreb, Rijeka and Split. A total of 20 physicians and 21 nurses participated in eight focus groups. The questions concerned everyday practices in end-of-life decision-making and their connection with interpersonal relationships between physicians, nurses, patients and their families. The constant comparative analysis method was used in the analysis of the data. Results: The analysis revealed two main themes that were the same among the professional groups as well as in both NICU and PICU units. The theme “critical illness” consisted of the following subthemes: the child, the family, myself and other professionals. The theme “end-of-life procedures” consisted of the following subthemes: breaking point, decision-making, end-of-life procedures, “spill-over” and the four walls of the ICU. The perceptions and experiences of end-of-life issues among nurses and physicians working in NICUs and PICUs share multiple common characteristics. The high variability in end-of-life procedures applied and various difficulties experienced during shared decision-making processes were observed. Conclusions: There is a need for further research in order to develop clinical and professional guidelines that will inform end-of-life decision-making, including the specific perspectives of everyone involved, and the need to influence policymakers.
Comparison of NH3 and N2O Plasma Treatments on Bi2O3 Sensing Membranes Applied in an Electrolyte–Insulator–Semiconductor Structure
Authors: Kao Chyuan-Haur , Chen Kuan-Lin , Chiu Yi-Shiang , Hao Lin Sang , Chen Shih-Ming , Li Ming-Hsien , Lee Ming-Ling , Chen Hsiang
Published: February 2022

In this study, bismuth trioxide (Bi2O3) membranes in an electrolyte–insulator–semiconductor (EIS) structure were fabricated with pH sensing capability. To optimize the sensing performance, the membranes were treated with two types of plasma—NH3 and N2O. To investigate the material property improvements, multiple material characterizations were conducted. Material analysis results indicate that plasma treatments with appropriate time could enhance the crystallization, remove the silicate and facilitate crystallizations. Owing to the material optimizations, the pH sensing capability could be greatly boosted. NH3 or N2O plasma treated-Bi2O3 membranes could reach the pH sensitivity around 60 mV/pH and show promise for future biomedical applications.
Dehydrogenation Coupling of Methane Using Catalyst-Loaded Proton-Conducting Perovskite Hollow Fiber Membranes
Authors: Song Jian , Hei Yuepeng , Li Claudia , Yang Naitao , Meng Bo , Tan Xiaoyao , Sunarso Jaka , Liu Shaomin
Published: February 2022

Catalytic dehydrogenation coupling of methane (DCM) represents an effective way to convert natural gas to more useful C2 products (C2H6, C2H4). In this work, BaCe0.85Tb0.05Co0.1O3-δ (BCTCo) perovskite hollow fiber membranes were fabricated by the combined phase inversion and sintering method. SrCe0.95Yb0.05O3-δ (SCYb) perovskite oxide was loaded as a catalyst onto the inner hollow fiber membrane surface, which promoted the CH4 conversion and the C2 hydrocarbon selectivity during the DCM reaction. The introduction of steam into the methane feed gas mixture elevated the C2 selectivity and yield due to the alleviation of coke deposition. Switching N2 to air as the sweep gas further increased the C2 selectivity and yield. However, the conversion of methane was limited by both the low permeability of the membrane and the insufficient catalytic activity of the catalyst, leading to low C2 yield.
New Insights on the Effects of Water on Polymer Inclusion Membranes Containing Aliquat 336 Derivatives as Carriers
Authors: Fontàs Clàudia , Vera Ruben , Anticó Enriqueta , Martínez de Yuso María del Valle , Rodríguez-Castellón Enrique , Benavente Juana
Published: February 2022

Surface characterization of polymer inclusion membranes (PIMs) using the polymers cellulose triacetate and polyvinyl chloride, containing different ionic liquids (ILs) as carriers, has been performed. Three different ILs have been tested: commercial trioctyl methylammonium chloride (Aliquat 336–AlqCl−) and two derivatives bearing the counter anion NO3− or SCN− (AlqNO3 and AlqSCN, respectively). Surface analysis was performed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) for both dry membranes and PIMs immersed for 4 days in ultrapure water to investigate the effect of the interaction of water with the membrane’s morphology and composition. XPS analysis of the PIMs revealed that immersion in ultrapure water causes a decrease in the atomic concentration percentage (A.C.%) of the specific IL atoms (Cl, S, and N) when compared with dry samples. Moreover, SEM images of the PIMs containing the IL AlqNO3 showed an alteration in the morphology of the membrane due to water contact at surface level, whereas no changes were observed at a bulk level. These changes in the surface composition of the water equilibrated PIMs may be associated with the solubilization of the IL in the water solution, which, therefore, may affect the reactivity of the membrane’s surface. To better understand this effect, PIMs containing both AlqCl and AlqNO3 as carriers were used for arsenic (V) transport. It was found that AlqCl was the most effective IL and that the effectivity of the PIM on As(V) removal was not affected after five cycles of the membrane’s reuse.
Determination of Location-Specific Solidification Cracking Susceptibility for a Mixed Dissimilar Alloy Processed by Wire-Arc Additive Manufacturing
Authors: Sridar Soumya , Sargent Noah , Wang Xin , Klecka Michael A. , Xiong Wei
Published: February 2022

Solidification cracking is a major obstacle when joining dissimilar alloys using additive manufacturing. In this work, location-specific solidification cracking susceptibility has been investigated using an integrated computational materials engineering (ICME) approach for a graded alloy formed by mixing P91 steel and Inconel 740H superalloy. An alloy mixture of 26 wt.% P91 and 74 wt.% Inconel 740H, with high configurational and total entropy, was fabricated using wire arc additive manufacturing. Microstructure characterization revealed intergranular solidification cracks in the FCC matrix, which increased in length along with the enrichment of Nb (~27 to 56 wt.%) and Cu (~87 wt.%) in the middle and top regions. DICTRA simulations to model location-specific solidification cracking susceptibility showed that the top region with the highest cooling rate (270 K/s) has the highest solidification cracking susceptibility in comparison with the middle and bottom regions. This is in good agreement with the experimentally observed varying crack length. From Scheil simulations, it was deduced that enrichment of Nb and Cu affected the solidification range as high as ~77%, in comparison with the matrix composition. The overall solidification cracking susceptibility and freezing range was highest for the 26 wt.% P91 alloy amongst the mixed compositions between P91 steel and 740H superalloy, proving that solidification characteristics play a major role in alloy design for additive manufacturing.
The Potential of Nrf2 Activation as a Therapeutic Target in Systemic Lupus Erythematosus
Authors: Barati Michelle T. , Caster Dawn J.
Published: February 2022

Inflammation and oxidative stress are well established in systemic lupus erythematosus (SLE) and are critical to the pathogenesis of autoimmune diseases. The transcription factor NF-E2 related factor 2 (Nrf2) is a central regulator of cellular anti-oxidative responses, inflammation, and restoration of redox balance. Accumulating reports support an emerging role for the regulation of Nrf2 in SLE. These include findings on the development of lupus-like autoimmune nephritis and altered immune cell populations in mice lacking Nrf2, as well as decreased Nrf2 abundance in the dendritic cells of patients with SLE. Nrf2-inducing agents have been shown to alleviate oxidative and inflammatory stress and reduce tissue injury in SLE mouse models. Since Nrf2 expression can be increased in activated T cells, the precise role of Nrf2 activation in different immune cell types and their function remains to be defined. However, targeting Nrf2 for the treatment of diseases associated with oxidative stress and inflammation, such as SLE, is promising. As investigation of Nrf2-inducing agents in clinical trials grows, defining the signaling and molecular mechanisms of action and downstream effects in response to different Nrf2-inducing agents in specific cells, tissues, and diseases, will be critical for effective clinical use.
Intravenous Arginine Administration Attenuates the Inflammatory Response and Improves Metabolic Profiles in Diet-Induced Obese Mice after Sleeve Gastrectomy
Authors: Chen Ya-Ling , Lin Ming-Tsan , Wang Wan-Hsuan , Yeh Sung-Ling , Yeh Chiu-Li
Published: February 2022

Sleeve gastrectomy (SG) is a bariatric surgery that can effectively reduce weight and improve obesity-associated comorbidities. However, surgical stress intensifies inflammation and imbalanced metabolic profiles. Arginine (Arg) is a nutrient with immunomodulatory and anti-inflammatory properties. This study evaluated the short-term effects of Arg administration on adipocyte inflammation and metabolic alterations in obese mice after SG. Mice were assigned to normal and high-fat diet (HFD) groups. After 16 weeks, the HFD group were divided to sham (SH), SG with saline (SS), or Arg (SA) groups. SS and SA groups were postoperatively injected with saline or Arg via the tail vein and sacrificed at day 1 or 3 after the SG, respectively. Results showed that obesity caused elevated plasma glucose and leptin levels. The SG operation enhanced the expression of inflammatory cytokines and macrophage infiltration in adipose tissues, whereas hepatocyte gene expressions associated with lipid β-oxidation were downregulated. Arg treatment reversed the expressions of β-oxidation-associated genes and reduced lipid peroxide production in the liver. Additionally, adipose tissue expressions of inflammatory chemokines were reduced, while the M2 macrophage marker increased after surgery. The findings suggest that postoperative Arg administration elicited more balanced hepatic lipid metabolism, polarized macrophages toward the anti-inflammatory type, and attenuated adipocyte inflammation shortly after SG.
Bacterial Ribosome Rescue Systems
Authors: Kurita Daisuke , Himeno Hyouta
Published: February 2022

To maintain proteostasis, the cell employs multiple ribosome rescue systems to relieve the stalled ribosome on problematic mRNA. One example of problematic mRNA is non-stop mRNA that lacks an in-frame stop codon produced by endonucleolytic cleavage or transcription error. In Escherichia coli, there are at least three ribosome rescue systems that deal with the ribosome stalled on non-stop mRNA. According to one estimation, 2–4% of translation is the target of ribosome rescue systems even under normal growth conditions. In the present review, we discuss the recent findings of ribosome rescue systems in bacteria.
Membrane Efflux Pumps of Pathogenic Vibrio Species: Role in Antimicrobial Resistance and Virulence
Authors: Stephen Jerusha , Lekshmi Manjusha , Ammini Parvathi , Kumar Sanath H. , Varela Manuel F.
Published: February 2022

Infectious diseases caused by bacterial species of the Vibrio genus have had considerable significance upon human health for centuries. V. cholerae is the causative microbial agent of cholera, a severe ailment characterized by profuse watery diarrhea, a condition associated with epidemics, and seven great historical pandemics. V. parahaemolyticus causes wound infection and watery diarrhea, while V. vulnificus can cause wound infections and septicemia. Species of the Vibrio genus with resistance to multiple antimicrobials have been a significant health concern for several decades. Mechanisms of antimicrobial resistance machinery in Vibrio spp. include biofilm formation, drug inactivation, target protection, antimicrobial permeability reduction, and active antimicrobial efflux. Integral membrane-bound active antimicrobial efflux pump systems include primary and secondary transporters, members of which belong to closely related protein superfamilies. The RND (resistance-nodulation-division) pumps, the MFS (major facilitator superfamily) transporters, and the ABC superfamily of efflux pumps constitute significant drug transporters for investigation. In this review, we explore these antimicrobial transport systems in the context of Vibrio spp. pathogenesis and virulence.
Both Constitutive and Infection-Responsive Secondary Metabolites Linked to Resistance against Austropuccinia psidii (Myrtle Rust) in Melaleuca quinquenervia
Authors: Moffitt Michelle C. , Wong-Bajracharya Johanna , Shuey Louise S. , Park Robert F. , Pegg Geoff S. , Plett Jonathan M.
Published: February 2022

Austropuccinia psidii is a fungal plant pathogen that infects species within the Myrtaceae, causing the disease myrtle rust. Myrtle rust is causing declines in populations within natural and managed ecosystems and is expected to result in species extinctions. Despite this, variation in response to A. psidii exist within some species, from complete susceptibility to resistance that prevents or limits infection by the pathogen. Untargeted metabolomics using Ultra Performance Liquid Chromatography with Ion Mobility followed by analysis using MetaboAnalyst 3.0, was used to explore the chemical defence profiles of resistant, hypersensitive and susceptible phenotypes within Melaleuca quinquenervia during the early stages of A. psidii infection. We were able to identify three separate pools of secondary metabolites: (i) metabolites classified structurally as flavonoids that were naturally higher in the leaves of resistant individuals prior to infection, (ii) organoheterocyclic and carbohydrate-related metabolites that varied with the level of host resistance post-infection, and (iii) metabolites from the terpenoid pathways that were responsive to disease progression regardless of resistance phenotype suggesting that these play a minimal role in disease resistance during the early stages of colonization of this species. Based on the classes of these secondary metabolites, our results provide an improved understanding of key pathways that could be linked more generally to rust resistance with particular application within Melaleuca.
Chemical Composition and Synergistic Potential of Mentha pulegium L. and Artemisia herba alba Asso. Essential Oils and Antibiotic against Multi-Drug Resistant Bacteria
Authors: Bekka-Hadji Fahima , Bombarda Isabelle , Djoudi Ferhat , Bakour Sofiane , Touati Abdelaziz
Published: February 2022

The essential oils were obtained by hydrodistillation from aerial parts of Mentha pulegium L. (M. pulegium L.) and Artemisia herba alba (A. herba alba) Asso. and analyzed by gas chromatography–flame ionization detector chromatograpy (GC–FID) and gaz chromatography–mass spectrometry (GC–MS). The antibacterial activities of the oils were determined by the disk diffusion method and a microdilution broth assay against six bacteria stains. The combinations of these essential oils with antibiotics were evaluated against two multi-drug-resistant bacteria strains: imipenem-resistant Acinetobacter baumannii (IRAB S3310) and methicillin-resistant Staphylococcus aureus (MRSA S19). The chemical analysis of M. pulegium essential oil revealed the presence of pulegone (74.8%) and neoisomenthol (10.0%). A. herba alba essential oil was characterized by camphor (32.0%), α-thujone (13.7%), 1,8-cineole (9.8%), β-thujone (5.0%), bornéol (3.8%), camphene (3.6%), and p-cymene (2.1%). All strains tested except Pseudomonas aeruginosa were susceptible to these oils. The combinations of essential oils with antibiotics exerted synergism, antagonism, or indifferent effects. The best effect was observed with A. herba alba essential oil in association with cefoxitin (CX) against MRSA S19. However, for IRAB S3310, the strongest synergistic effect was observed with M. pulegium in association with amikacin (AK). This study demonstrated that M. pulegium and A. herba alba essential oils have antibacterial activities which could be potentiated by antibiotics especially in the case of IRAB S3310.
Investigation of the Crystallization Characteristics of Intermediate States in Ge2Sb2Te5 Thin Films Induced by Nanosecond Multi-Pulsed Laser Irradiation
Authors: Du Jia , Zhou Jun , Zhang Lianzhen , Yang Na , Ding Xin , Zhang Jin
Published: February 2022

Laser pulses can be utilized to induce intermediate states of phase change materials between amorphous and crystalline phases, making phase change materials attractive and applicable for multi-level storage applications. In this paper, intermediate states of Ge2Sb2Te5 thin films induced via employing a nanosecond multi-pulse laser with different energy and pulse duration were performed by Raman spectroscopy, reflection measurement and thermal simulations. Upon laser-crystallized Ge2Sb2Te5 films, optical functions change drastically, leading to distinguishable reflectivity contrasts of intermediate states between amorphous and crystalline phases due to different crystallinity. The changes in optical intensity for laser-crystallized Ge2Sb2Te5 are also accompanied by micro-structure evolution, since high-energy and longer pulses result in higher-level intermediate states (corresponding to high reflection intensity) and largely contribute to the formation of stronger Raman peaks. By employing thermal analysis, we further demonstrated that the variations of both laser fluence and pulse duration play decisive roles in the degree of crystallinity of Ge2Sb2Te5 films. Laser fluence is mainly responsible for the variations in crystallization temperature, while the varying pulse duration has a great impact on the crystallization time. The present study offers a deeper understanding of the crystallization characteristic of phase change material Ge2Sb2Te5.
Ru@Carbon Nanotube Composite Microsponge: Fabrication in Supercritical CO2 for Hydrogenation of p-Chloronitrobenzene
Authors: Ge Xianghong , Liu Hui , Ding Xingxing , Liu Yanyan , Li Xingsheng , Wu Xianli , Li Baojun
Published: February 2022

Novel heterogeneous catalysts are needed to selectively anchor metal nanoparticles (NPs) into the internal space of carbon nanotubes (CNTs). Here, supercritical CO2 (SC-CO2) was used to fabricate the Ru@CNT composite microsponge via impregnation. Under SC-CO2 conditions, the highly dispersive Ru NPs, with a uniform diameter of 3 nm, were anchored exclusively into the internal space of CNTs. The CNTs are assembled into a microsponge composite. The supercritical temperature for catalyst preparation, catalytic hydrogenation temperature, and time all have a significant impact on the catalytic activity of Ru@CNTs. The best catalytic activity was obtained at 100 °C and 8.0 MPa: this gave excellent selectivity in the hydrogenation of p-chloronitrobenzene at 100 °C. This assembly strategy assisted by SC-CO2 will be promising for the fabrication of advanced carbon composite powder materials.
High-Stability Ti3C2-QDs/ZnIn2S4/Ti(IV) Flower-like Heterojunction for Boosted Photocatalytic Hydrogen Evolution
Authors: Yang Liqin , Chen Zhihong , Wang Xin , Jin Mingliang
Published: February 2022

The practical application of photocatalytic H2-evolution is greatly limited by its sluggish charge separation, insufficient active sites, and stability of photocatalysts. Zero-dimensional (0D) Ti3C2 MXene quantum dots (MQDs) and amorphous Ti(IV) have been proven to be potential substitutes for noble co-catalyst to accelerate the separation of photogenerated electron-hole pairs and prevent the self-oxidation of photocatalysts, leading to better photocatalytic H2-evolution performance with long-term stability. In this study, amorphous Ti(IV) and MQDs co-catalysts were successfully deposited on ZnIn2S4 (ZIS) microspheres composed of ultra-thin nanosheets via a simple impregnation and self-assembly method (denoted as MQDs/ZIS/Ti(IV)). As expected, the optimal MQDs/ZIS/Ti(IV) sample exhibited a photocatalytic H2-evolution rate of 7.52 mmol·g−1·h−1 and excellent photostability without metallic Pt as the co-catalyst in the presence of Na2S/Na2SO3 as hole scavenger, about 16, 4.02 and 4.25 times higher than those of ZIS, ZIS/Ti(IV), and MQDs/ZIS, respectively. The significantly enhanced photocatalytic H2-evolution activity is attributed to the synergistic effect of the three-dimensional (3D) flower-like microsphere structure, the amorphous Ti(IV) hole co-catalyst, and a Schottky junction formed at the ZIS–MQDs interface, which offers more active sites, suppresses self-photocorrosion, and photo-generates the charge recombination of ZIS.