bluuebunny/crossref_metadata_2025 huggingface dataset:
Can Exhaled Carbon Monoxide Be Used as a Marker of Exposure? A Cross-Sectional Study in Young Adults
Authors: Pan Ke-Ting , Leonardi Giovanni S. , Ucci Marcella , Croxford Ben
Published: November 2021

Carbon monoxide (CO) poisoning is a major public health issue worldwide. People are exposed to CO in their daily lives, with one of the common sources of CO being cigarette smoking. Inhalation of CO leads to elevated carboxyhaemoglobin (COHb) levels in the blood and also in exhaled CO concentration. Several factors have been shown to affect COHb concentration and COHb half-life. However, factors affecting exhaled CO concentration and exhaled CO half-life are not well understood. The present study aimed to investigate the potential factors related to baseline exhaled CO concentration and exhaled CO half-life among smokers. A cross-sectional study was conducted between 26 January and 30 June 2019, and young adults were recruited into the study. A total of 74 participants (mean age: 27.1 years, 71.6% males and 28.4% females) attended the study. They were invited to complete a questionnaire, including demographic, physiological, and behavioural factors. Then, exhaled CO measurements were taken. These measurements were taken before and after smoking a single cigarette for smokers and only once for non-smokers. The average baseline exhaled CO concentration was 6.9 ± 4.9 ppm for smokers and 1.9 ± 0.5 ppm for non-smokers. The mean of exhaled CO half-life was around 273.3 min (4.6 h) for smokers. No difference was seen in exhaled CO half-life between light smokers and heavy smokers in the smoking group. Gender and cigarettes smoked weekly affected baseline exhaled CO in smokers. Even though height seemed to positively associate with exhaled CO half-life, the relationship disappeared when adjusting by gender and weight. Therefore, exhaled CO could be used as a marker of CO exposure, but we cannot ignore the factors mentioned in the study. For future study, considering factors related to smoking habits and smoking style are recommended as these may affect total inhaled CO.
Spatiotemporal Changes of Chemical Fertilizer Application and Its Environmental Risks in China from 2000 to 2019
Authors: Guo Yuanzhi , Wang Jieyong
Published: November 2021

Chemical fertilizers are important inputs in agricultural production. They not only increase crop yield but also bring many negative effects, such as agricultural non-point source pollution. Therefore, a scientific understanding of the regional differences in chemical fertilizer application and its environmental risks is of significance to promote China’s agricultural development. In this study, we analyzed the spatiotemporal pattern of chemical fertilizer application intensity (CFAI) in China since 2000, evaluated the environmental risks of provincial CFAI, and investigated the internal mechanism behind them. The results showed that the total amount and intensity of chemical fertilizer application in China from 2000 to 2019 presented a trend of increasing first and then decreasing. In 2000 and 2019, provincial CFAI in eastern China was generally higher than that in central and western China, and the environmental risks of provincial CFAI were spatially characterized by “high in the north and low in the south”. Factors such as poor soil conditions, unreasonable farming structure and backward fertilization methods are the main reasons for the continuous increase in the total amount and intensity of chemical fertilizer application, while the construction of ecological civilization and the transformation of society and economy are the main reasons for their decline. Finally, measures such as targeted fertilization, adjusting the use structure of chemical fertilizers, improving fertilization methods and replacing chemical fertilizers with organic fertilizers are proposed to promote the quantity reduction and efficiency increase of chemical fertilizer application in China.
Is Social Media Spreading Misinformation on Exercise and Health in Brazil?
Authors: Marocolo Moacir , Meireles Anderson , de Souza Hiago Leandro Rodrigues , Mota Gustavo Ribeiro , Oranchuk Dustin Jay , Arriel Rhaí André , Leite Laura Hora Rios
Published: November 2021

Instagram (IG) reaches millions of people, sharing personal content and all kinds of information, including those related to exercise and health. However, the scientific quality of the posted information is questionable. Thus, this study aimed to analyze whether exercise and health information posted by popular Brazilian IG influencers has technical-scientific accuracy. A personal IG account was created to identify Brazilian IG profiles. The inclusion criteria of the accounts were: (1) having 50% of all the shared posts related to topics about exercise and health, such as nutrition, health and wellness, medicine, or physical fitness; and (2) having over 100,000 followers. Qualitative analysis revealed a low quality percentage (38.79 ± 25.43%) for all analyzed posts. Out of all the posts, only 13 (~2.7%) cited a reference endorsing the information. Moreover, the higher quality-ratio score of the posts was not directly associated with the higher educational qualification of the influencers (r = 0.313; p = 0.076). Nevertheless, the number of followers was inversely correlated with the educational qualification of the influencers (r = −0.450; p = 0.009), but not with the quality-ratio score of the posts (r = −0.178 p = 0.322). We conclude that prominent Brazilian IG influencers disseminate low-quality information about exercise and health, contributing to the wide-spreading of misinformation to millions of followers.
In the Eye of the Beholder: The Impact of Intergenerational Programs from the Perspectives of Their Different Stakeholders
Authors: Cohen-Mansfield Jiska
Published: November 2021

Since most evaluations of intergenerational programs (IGPs) focus on the perspective of a single stakeholder group concerning the benefit for themselves, we compared perceptions of multiple stakeholders: older adults, younger adults, and IGP organizers concerning the impact of IGPs on older and young participants. Using a mixed-methods approach, we collected data from thirteen community-based IGPs. The quantitative analyses included a comparison of the different stakeholder groups via ANOVAs and chi-square analyses. In order to identify the reasons for different attribution ratings among stakeholders, we conducted a qualitative analysis of the stakeholders’ comments and responses to open-ended questions using a thematic analysis approach. Overall, participants rated benefits to themselves lower than attributed to them by their counterparts. Differences in ratings may be explained by differences in expectations and needs, cognitive dissonance, as well as a lack of awareness about other participants’ experiences. Given the discrepancies in perception of impact, it is vital to seek input from all stakeholders in order to understand their respective needs and expectations, construct a balanced evaluation, and improve IGP processes and outcomes. Studying a single stakeholder group for project evaluation is likely to provide only one perspective, whereas including all points of view provides a more complete picture.
Cardiac Rehabilitation Early after Sternotomy Using New Assistive VR-Enhanced Robotic Exoskeleton—Study Protocol for a Randomised Controlled Trial
Authors: Mocan Mihaela , Vlaicu Sonia Irina , Farcaș Anca Daniela , Feier Horea , Dragan Simona , Mocan Bogdan
Published: November 2021

(1) Background and objective: Cardiac rehabilitation (CR) means delivering health education by structured exercises with the means of risk reduction, in a cost-effective manner. Well-conducted CR improves functional capacity, decreases re-hospitalization, and reduces mortality up to 25%. We bring to attention the protocol of a randomised control trial with the aim of validating the prototype of an assistive upper-body robotic exoskeleton system enhanced with a non-immersive virtual reality exergame (CardioVR-ReTone) in patients who undergone cardiac surgery. (2) Methods: Description of the CardioVR-ReTone system and the technical specification, followed by the group selection, randomization and evaluated variables. (3) Expected results: The primary outcome measurement is the modification of life quality at the end of the CR exercise training program. Secondary outcomes will encompass measurements of sternal stability, muscular activity, cardiac response to exercise, pain level and compliance/adherence to CR. (4) Conclusions: Implementing these novel features of the CardioVR-ReTone system, addressability, and efficacy of CR, so problematic in certain situations and especially in cardiac surgery, will be greatly facilitated, being independent of the skills and availability of the rehabilitation therapist.
Assessing the Potential Impact of Land Use on Carbon Storage Driven by Economic Growth: A Case Study in Yangtze River Delta Urban Agglomeration
Authors: Qiao Wenyi , Guan Weihua , Huang Xianjin
Published: November 2021

Economic development and land-use change can strongly affect terrestrial ecosystems’ carbon balance. This paper quantifies the changes in land use of Yangtze River Delta urban agglomeration (YRD) in 2020 and 2035 under three economic growth scenarios, exploring the concurrent impact on carbon storage. The results showed that the land carbon storage of YRD had decreased by 1453.80 Tg in 2000–2020, and will continue to decrease by 982.38 Tg, 1417.62 Tg, and 1636.21 Tg under the scenarios of a slow, medium, and rapid economic growth from 2020 to 2035, respectively. The large-scale occupation of cultivated land and woodland for construction land caused by economic development and population growth was an important reason. The occupation of cultivated land by construction land in Nanjing, Shanghai, and its surrounding areas had further intensified, while the reduction in carbon storage caused by the reduction in woodland had become more prominent in Hangzhou, Shaoxing, Jinhua, and the surrounding areas.
Changes in Physical Activity and Sedentary Behaviour in Cardiovascular Disease Patients during the COVID-19 Lockdown
Authors: van Bakel Bram M.A. , Bakker Esmée A. , de Vries Femke , Thijssen Dick H.J. , Eijsvogels Thijs M.H.
Published: November 2021

The COVID-19 lockdown has been associated with physical inactivity. We prospectively evaluated changes in moderate-to-vigorous physical activity (MVPA) and sedentary time (ST) among 1565 cardiovascular disease (CVD) patients using validated questionnaires at 5 weeks after lockdown initiation (i.e., baseline, April 2020) and at every 4 subsequent weeks, until July 2020. Multivariate mixed model analyses were performed to identify whether age, sex, CVD-subtype, lockdown adherence and mental health factors impacted changes in physical (in)activity. Patients were 67 (interquartile range: 60–73) years and primarily diagnosed with coronary artery disease. Time spent in MVPA was 143 min/day (95% confidence interval (CI) 137; 148) at baseline. Female sex, heart-failure, fear of COVID-19 infection and limited possibilities for physical activity were independently associated with lower levels of MVPA across time. After adjusting for confounders, overall MVPA did not change. ST was 567 (95% CI 555; 578) min/day at baseline. Lack of social contact, limited possibilities for physical activity and younger age were independently associated with higher levels of ST. After adjusting for confounders, ST progressively increased following 8 (Δ+19.7 (95% CI 0.4; 39.0)) and 12 weeks (Δ+25.2 (95% CI 5.4; 47.1) min/day) of lockdown. Despite a phased relaxation of the lockdown, CVD patients progressively increased ST and reported no change in MVPA. This highlights the need to target physical inactivity during and beyond the COVID-19 pandemic.
A Rapid Realist Review of Quality Care Process Metrics Implementation in Nursing and Midwifery Practice
Authors: Teeling Sean Paul , Davies Carmel , Barnard Marlize , O’Connor Laserina , Coffey Alice , Lambert Veronica , McNamara Martin , Tuohy Dympna , Frawley Timothy , Redmond Catherine , Somanadhan Suja , Casey Mary , Corcoran Yvonne , Doody Owen , O’Brien Denise , Noonan Maria , Smith Rita , Bradshaw Carmel , Murphy Sylvia , Dore Liz , Lyons Rosemary , McGeehan Máire , Gallen Anne
Published: November 2021

Quality measurement initiatives promote quality improvement in healthcare but can be challenging to implement effectively. This paper presents a Rapid Realist Review (RRR) of published literature on Quality Care-Process Metrics (QCP-M) implementation in nursing and midwifery practice. An RRR informed by RAMESES II standards was conducted as an efficient means to synthesize evidence using an expert panel. The review involved research question development, quality appraisal, data extraction, and evidence synthesis. Six program theories summarised below identify the key characteristics that promote positive outcomes in QCP-M implementation. Program Theory 1: Focuses on the evidence base and accessibility of the QCP-M and their ease of use by nurses and midwives working in busy and complex care environments. Program Theory 2: Examines the influence of external factors on QCP-M implementation. Program Theory 3: Relates to existing cultures and systems within clinical sites. Program Theory 4: Relates to nurses’ and midwives’ knowledge and beliefs. Program Theory 5: Builds on the staff theme of Programme Theory four, extending the culture of organizational learning, and highlights the meaningful engagement of nurses and midwives in the implementation process as a key characteristic of success. Program Theory 6: Relates to patient needs. The results provide nursing and midwifery policymakers and professionals with evidence-based program theory that can be translated into action-orientated strategies to help guide successful QCP-M implementation.
A Field Study of Work Type Influence on Air Traffic Controllers’ Fatigue Based on Data-Driven PERCLOS Detection
Authors: Zhang Jianping , Chen Zhenling , Liu Weidong , Ding Pengxin , Wu Qinggang
Published: November 2021

The fatigue of air traffic controllers (ATCOs) on duty seriously threatens air traffic safety and needs to be managed. ATCOs perform several different types of work, with each type of work having different characteristics. Nonetheless, the influence of work type on an ATCO’s fatigue has yet to be demonstrated. Here, we present a field study in which the fatigue of ATCOs working in two types of work was compared based on an optimized data-driven method that was employed to detect the percentage of eyelid closure over the pupil over time (PERCLOS). Sixty-seven ATCOs working within two typical jobs (i.e., from the terminal control unit (TCU) and area control unit (ACU)) were recruited, and their fatigue was detected immediately before and after shift work using PERCLOS. Using a Spearman correlation test analysis, the results showed that the influence of work type on an ATCO’s fatigue had interesting trends. Specifically, the ATCOs at the TCU who handle departures and arrivals, which include converging with and maneuvering around conflicts, retain normal circadian rhythms. Their fatigue was significantly influenced by the various demands from tasks focusing on sequencing and conflict resolution and by the time phase of a normal circadian rhythm. At the ACU, ATCOs manage flights that are mainly on route, causing monotonous monitoring and routine reporting tasks, and the ATCOs generally have frequent night shifts to handle overflights. Their fatigue was significantly influenced by the demand characteristics from tasks, but changes in fatigue rule were not consistent with a normal circadian rhythm, revealing that the ATCOs’ circadian rhythms may have already been slightly disturbed. Furthermore, the interactions between task demand and circadian rhythm with an ATCO’s fatigue were significantly observed in ATCOs working in the TCU but not in those in the ACU. This study provides first evidence that an ATCO’s work type influences his or her fatigue. This discovery may incite stakeholders to consider work type in the management of employee fatigue, not only in the civil aviation industry but also in other transport industries.
Loneliness and Mental Health: The Mediating Effect of Perceived Social Support
Authors: Hutten Elody , Jongen Ellen M. M. , Vos Anique E. C. C. , van den Hout Anja J. H. C. , van Lankveld Jacques J. D. M.
Published: November 2021

Social connectedness is a fundamental human need. The Evolutionary Theory of Loneliness (ETL) predicts that a lack of social connectedness has long-term mental and physical health consequences. Social support is a potential mechanism through which loneliness influences health. The present cross-sectional study examined the relationship between loneliness and mental health, and the mediating effects of social support in a Dutch adult sample (N = 187, age 20 to 70). The health variables included in the study are anxiety, depression, somatic symptoms as measured by the SCL-90, and the DSM-5 diagnosis somatic symptom disorder. The results indicated that social support partially mediated the relationship between loneliness and anxiety, depression, and somatic symptoms. These results indicate that social support partially explains the relationship between loneliness and physical and mental health issues. The relationship between loneliness and being diagnosed with somatic symptom disorder was not mediated by social support. This suggests that the mechanisms through which loneliness relates to either somatic symptoms or somatic symptom disorder are different.
Changes in Risk in Medium Business Plating and Paint Manufacturing Plants following the Revision of the Korean Chemical Accident Prevention System
Authors: Lee Hyo Eun , Kim Min-Gyu , Yoon Seok J. , Huh Da-An , Moon Kyong-Whan
Published: November 2021

Chemical accidents can occur anywhere. The need for chemical management in Korea was realized following the 2012 Gumi hydrofluoric acid accident in 2012. The Chemicals Control Act was enacted in 2015. This system evaluates the risks (high, medium, low) and consequent safety management at all plants that handle hazardous chemical substances. However, the system was criticized as excessive when most plants were designated high-risk without considering their size. Thus, laboratories and hospitals handling very small quantities were subject to regulation. Accordingly, in 2021 Korea revised the system to include off-site consequence analyses and a Korean-style risk analysis. Plants handling very small quantities, such as laboratories and hospitals, were exempt from regulation. In this study, changes in risk were examined for four medium-sized plating and paint manufacturing plants. Under the previous system, all four factories were judged as high-risk groups. In particular, the paint manufacturing plant A, which has an underground storage tank, received a medium risk like the plating plant C, although the possibility of a chemical accident was lower than that of other plants. However, in the changed system, all plants were changed to the low-risk group. In the Korean-style risk analysis, it is possible to see at a glance what is lacking in the plants, such as cooperation between local residents and local governments and the construction of safety facilities according to the type of accident scenario. The revised system is a reasonable regulation for medium business plants.
Validation of an Arabic Version of the Self-Efficacy for Appropriate Medication Use Scale
Authors: Alhazzani Hawazin , AlAmmari Ghaida , AlRajhi Nouf , Sales Ibrahim , Jamal Amr , Almigbal Turky H. , Batais Mohammed A. , Asiri Yousif A. , AlRuthia Yazed
Published: November 2021

Background: Medication adherence is essential for optimal treatment outcomes in patients with chronic diseases. Medication nonadherence compromises patient clinical outcomes and patient safety as well as leading to an increase in unnecessary direct and indirect medical costs. Therefore, early identification of non-adherence by healthcare professionals using medication adherence scales should help in preventing poor clinical outcomes among patients with chronic health conditions, such as diabetes and hypertension. Unfortunately, there are very few validated medication adherence assessment scales in Arabic. Thus, the aim of this study was to validate a newly translated Arabic version of the Self-Efficacy for Appropriate Medication Use Scale (SEAMS) among patients with chronic diseases. Methods: In this single-center cross-sectional study that was conducted between March 2019 and March 2021 at the primary care clinics of King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia, the English version of SEAMS was translated to Arabic using the forward–backward method and piloted among 22 adults (≥18 yrs.) with chronic diseases. The reliability of the newly translated scale was examined using the test–retest and Cronbach’s alpha methods. Exploratory and confirmatory factor analyses were conducted to examine the construct validity of the Arabic version of SEAMS. Results: The number of patients who consented to participate and filled out the questionnaire was 202. Most of the participants were males (69.9%), aged ≥50 years (65.2%), and had diabetes (96.53%). The 13-item Arabic-translated SEAMS mean score was 32.37 ± 5.31, and the scale showed acceptable internal consistency (Cronbach’s alpha = 0.886) and reliability (Intraclass correlation coefficient = 0.98). Total variance of the 13-item Arabic-SEAMS could be explained by two factors as confirmed by the factor analysis. Conclusion: The Arabic version of SEAMS should help in detecting poor self-efficacy for medication adherence among Arabic-speaking patient populations with chronic diseases, such as diabetes and hypertension. Future studies should examine its validity among more diverse patient populations in different Arabic-speaking countries.
Turbine Broadband Noise Predictions Using Linearised Frequency Domain Navier-Stokes Solvers
Authors: Blázquez-Navarro Ricardo , Corral Roque
Published: November 2021

A linear frequency domain Navier-Stokes solver is used to retain the influence of turning, thickness, and main geometric parameters on turbine broadband noise. The methodology has been applied to predict the broadband interaction noise produced by a representative low-speed low-pressure turbine section. The differences in the spectra with respect to those yielded by state-of-the-art flat plate based methodologies are up to 6 dB. The differences are caused by multiple effects that semi-analytical methodologies do not account for. The most important are blade thickness and turning, which have been studied separately to quantify their impact on the broadband noise footprint. The influence of changing the turbine operating conditions has been discussed as well. The outlet sound pressure level scales with the third and second power of the inlet and outlet Mach number, respectively, for constant turbulence intensity, within most of the frequency range considered.
Class-Switching of B Lymphocytes by DNA and Cell Immunization for Stereospecific Monoclonal Antibodies against Native GPCR
Authors: Isozaki Yushi , Tsumoto Kanta , Tomita Masahiro
Published: November 2021

To develop efficient applications of monoclonal antibodies for therapeutic purposes, stereospecific recognition of the target antigens is needed. DNA immunization is one of the best methods for sensitizing B lymphocytes that can produce conformation-specific antibodies. Here we verified the class-switching of monoclonal antibodies by DNA immunization followed by cell immunization for the generation of stereospecific monoclonal antibodies against native G protein-coupled receptor (GPCR) using the optimized stereospecific targeting (SST) technique. This technology facilitates the efficient selection of sensitized B lymphocytes through specific interaction with the intact antigen via B-cell receptors (BCRs). We demonstrate that multiple DNA immunizations followed by a single cell immunization in combination with a longer sensitization period (three to four months) are an appropriate sensitizing strategy for the generation of IgG-type stereospecific monoclonal antibodies by class-switching, and the characteristics of antibody production could be transferred to hybridoma cells provided by the optimized SST technique.
In Vitro Weight Loss of Dental Composite Resins and Glass-Ionomer Cements Exposed to a Challenge Simulating the Oral Intake of Acidic Drinks and Foods
Authors: Colombo Marco , Gallo Simone , Chiesa Marco , Poggio Claudio , Scribante Andrea , Zampetti Paolo , Pietrocola Giampiero
Published: November 2021

Specific conditions of the oral cavity, such as intake of acidic drinks, foods, and drugs, represent a damage both for teeth as well as restorative materials. The aim of this in vitro study is to assess the influence of an acidic challenge on the weight loss of biomimetic restorative dental materials (composite resins and glass-ionomer cements, respectively). Seven products recently available in the marked have been tested in this study for the two kinds of materials, respectively. Resin composites were divided into Groups 1A–7A, whereas glass-ionomer cements into Groups 1B–7B. A total of six samples was considered for each group, among which two were stored into distilled water (control samples) whereas the other four were immersed into soft drink (Coca-Cola, Coca-Cola Company, Milano, Italy) for 7 days. Respectively, after 1, 3 and 7 days, weight was assessed for each sample and the percentage weight loss was calculated. For all the composite resins (Groups 1A–7A), no significant intergroup or intragroup differences occurred for the weight loss values (p > 0.05). Conversely, all glass-ionomers (Groups 1B–7B) showed a significant and progressive weight loss after 1, 3, and 7 days of acid challenge (p < 0.05) (intragroup differences). This reduction was significantly lower in case of GC Equia Forte + Coat and ChemFil Rock, with respect to the other cements (p < 0.05) (intergroup differences). In conclusions, all the biomimetic composite resins showed a reliable behavior when exposed to acidic erosion, whereas glass-ionomers cements generally tended to solubilize. However, the additional use of a protective layer above these latter materials could reduce this event. Despite these results appear to be interesting from a clinical point of view, future morphological evaluations should be conducted to evaluate the superficial changes of the materials after acidic explosion.
Influence of Remote Internal Tides on the Locally Generated Internal Tides upon the Continental Slope in the South China Sea
Authors: Guo Zheng , Cao Anzhou , Wang Shuya
Published: November 2021

In this paper, the M2 internal tides (ITs) originating from the continental slope in the South China Sea are studied using the CROCO model. The simulation results show that there are two origins of ITs on the continental slope: at 118°–119.5° E along 22° N near the southern entrance of the Taiwan Strait and at 117°–118° E along 20° N near Dongsha Island. The local generation of ITs is greatly influenced by the ITs that radiate from the Luzon Strait (LS). The integrated conversion at the first generation site is increased by 31% to 0.42 GW compared to the case where the LS is excluded from the simulation region. Its maximum energy flux almost doubles to 2.5 kW/m, which is 10% of the westward component. The existence of the other IT beams from Dongsha Island is attributed to the ITs from the LS. The local generation on the continental slope changes when remotely generated ITs alter the amplitudes and phases of the bottom pressure perturbation. These results indicate that the ITs originating from the LS contribute to the spatial variation of ITs in the SCS by modulating the IT generation on the continental slope.
Dependence of Transport and External Cost Variables on Transportation Route Length
Authors: Vukić Luka , Kraemer Iven
Published: November 2021

External transport costs are becoming an increasingly important factor in the choice of transport routes. According to sustainability principles, the first choice criterion should be the route with the least harmful impact on the environment and health. Sometimes the criteria for transportation costs are in conflict with environmental ones. There is a need to optimize them to maintain the trend of sustainable transport development. Cost and external cost behaviors of intermodal maritime–rail container transport from China over different European ports to central European destinations were examined. The aim was to determine the differences in dependency on transport route length of these two variables that are able to partly explain their different features. The complete functional dependency of external cost in maritime transport and transport cost in rail transport on route length is determined. External cost dependence on the transport route length in the railway segment was strong but incomplete. Maritime external cost share in the total external cost of combined transport was at least 83%. The weak negative dependence of maritime transport cost on route length probably reflects efforts to maintain the competitiveness of consolidated longer routes. This article contributes to the ongoing discussion of seaport competitiveness within Europe.
Sustainable Biocatalytic Procedure for Obtaining New Branched Acid Esters
Authors: Montiel María Claudia , Asensi Miguel , Gimeno-Martos Silvia , Máximo Fuensanta , Bastida Josefa
Published: November 2021

Biocatalytic synthesis of 2-ethylhexyl 2-methylhexanoate is described in this work for the first time. This branched-chain ester is suitable for use at low temperatures in numerous applications. The immobilized lipase Novozym® 435 has demonstrated its ability to catalyze the ester synthesis from 2-ethylhexanol and 2-methylhexanoic acid in a solvent-free medium. The high reaction times that are required result in a loss of alcohol by evaporation, which must be compensated for with an excess of this substrate if high conversions are to be achieved. Therefore, two strategies are established: 70 °C with a 10% excess of alcohol, which requires a longer operating time and provides conversions of 97%, and 80 °C with a 20% excess of alcohol, which allows for the achievement of a 99% conversion in a shorter time. The optimal reaction conditions have been chosen based on reusability of the enzyme, process productivity, green metrics and preliminary economic study. When the synthesis is carried out under the best conditions (70 °C, 10% molar excess of alcohol and six uses of the immobilized enzyme) a productivity of 203.84 kg product × kg biocatalyst−1 is attained. The biocatalytic procedure matches many of the objectives of “green chemistry” and is suitable to be scaled up and used in industrial manufacturing.
Non-Linear Response of Cable-Mass-Spring System in High-Rise Buildings under Stochastic Seismic Excitation
Authors: Weber Hanna , Kaczmarczyk Stefan , Iwankiewicz Radosław
Published: November 2021

In high-rise buildings earthquake ground motions induce bending deformation of the host structure. Large dynamic displacements at the top of the building can be observed which in turn lead to the excitation of the cables/ropes within lift installations. In this paper, the stochastic dynamics of a cable with a spring-damper and a mass system deployed in a tall cantilever structure under earthquake excitation is considered. The non-linear system is developed to describe lateral displacements of a vertical cable with a concentrated mass attached at its lower end. The system is moving slowly in the vertical direction. The horizontal displacements of the main mass are constrained by a spring-viscous damping element. The earthquake ground motions are modelled as a filtered Gaussian white noise stochastic process. The equivalent linearization technique is then used to replace the original non-linear system with a linear one with the coefficients determined by utilising the minimization of the mean-square error between both systems. Mean values, variances and covariances of particular random state variables have been obtained by using the numerical calculation. The received results were compared with the deterministic response of the system to the harmonic process and were verified against results obtained by Monte Carlo simulation.
Behavior of Alkali-Activated Fly Ash through Underwater Placement
Authors: Yahya Zarina , Abdullah Mohd Mustafa Al Bakri , Li Long-yuan , Burduhos Nergis Dumitru Doru , Hakimi Muhammad Aiman Asyraf Zainal , Sandu Andrei Victor , Vizureanu Petrica , Razak Rafiza Abd
Published: November 2021

Underwater concrete is a cohesive self-consolidated concrete used for concreting underwater structures such as bridge piers. Conventional concrete used anti-washout admixture (AWA) to form a high-viscosity underwater concrete to minimise the dispersion of concrete material into the surrounding water. The reduction of quality for conventional concrete is mainly due to the washing out of cement and fine particles upon casting in the water. This research focused on the detailed investigations into the setting time, washout effect, compressive strength, and chemical composition analysis of alkali-activated fly ash (AAFA) paste through underwater placement in seawater and freshwater. Class C fly ash as source materials, sodium silicate, and sodium hydroxide solution as alkaline activator were used for this study. Specimens produced through underwater placement in seawater showed impressive performance with strength 71.10 MPa on 28 days. According to the Standard of the Japan Society of Civil Engineers (JSCE), the strength of specimens for underwater placement must not be lower than 80% of the specimen’s strength prepared in dry conditions. As result, the AAFA specimens only showed 12.11% reduction in strength compared to the specimen prepared in dry conditions, thus proving that AAFA paste has high potential to be applied in seawater and freshwater applications.
Evaluation of Gamma Radiation Properties of Four Types of Surgical Stainless Steel in the Energy Range of 17.50–25.29 keV
Authors: Marashdeh Mohammad , Al-Hamarneh Ibrahim F.
Published: November 2021

In this study, the gamma radiation properties of four types of surgical-grade stainless steel (304, 304L, 316 and 316L) were investigated. The effective atomic number Zeff, effective electron density Neff and half-value layer (HVL) of four types of surgical-grade stainless steel were determined via the mass attenuation coefficient (μ/ρ). The μ/ρ coefficients were determined experimentally using an X-ray fluorescence (XRF) technique and theoretically via the WinXCOM program. The Kα1 of XRF photons in the energy range between 17.50 and 25.29 keV was used from pure metal plates of molybdenum (Mo), palladium (Pd), silver (Ag) and tin (Sn). A comparison between the experimental and theoretical values of μ/ρ revealed that the experimental values were lower than the theoretical calculations. The relative differences between the theoretical and experimental values were found to decrease with increasing photon energy. The lowest percentage difference between the experimental and theoretical values of μ/ρ was between −6.17% and −9.76% and was obtained at a photon energy of 25.29 keV. Sample 316L showed the highest value of μ/ρ at the energies 21.20, 22.19 and 25.29 keV. In addition, the measured results of Zeff and Neff for all samples behaved similarly in the given energy range and were found to be in good agreement with the calculations. The equivalent atomic number (Zeff) of the investigated stainless-steel samples was calculated using the interpolation method to compare the samples at the same source energy. The 316L stainless steel had higher values of μ/ρ, Zeff and Zeq and lower values of HVL compared with the other samples. Therefore, it is concluded that the 316L sample is more effective in absorbing gamma radiation.
Effects of Composite Coatings Functionalized with Material Additives Applied on Textile Materials for Cut Resistant Protective Gloves
Authors: Kropidłowska Paulina , Jurczyk-Kowalska Magdalena , Irzmańska Emilia , Płociński Tomasz , Laskowski Radosław
Published: November 2021

The objective of the present work was to evaluate the effects of different types of particles added to a polymer paste applied onto a textile carrier on the cut resistance of the resulting material. Knitted aramid textile samples were coated in laboratory conditions using a polymer paste that was functionalized with 12 types of reinforcing particles of different chemical compositions and size fractions. Cut resistance was tested in accordance with the standard EN ISO 13997:1999 and the results were subjected to statistical analysis. The effects of additive particles on the microstructure of the polymeric layer were assessed by means of scanning electron microscopy. The type and size of the particles affected the cut resistance of the functionalized knitted fabric. They were also found to change the morphology of the porous structure. Composite coatings containing the smallest additive particles exhibited the best cut resistance properties.
Discrete Pseudo Lindley Distribution: Properties, Estimation and Application on INAR(1) Process
Authors: Irshad Muhammed , Chesneau Christophe , D’cruz Veena , Maya Radhakumari
Published: November 2021

In this paper, we introduce a discrete version of the Pseudo Lindley (PsL) distribution, namely, the discrete Pseudo Lindley (DPsL) distribution, and systematically study its mathematical properties. Explicit forms gathered for the properties such as the probability generating function, moments, skewness, kurtosis and stress–strength reliability made the distribution favourable. Two different methods are considered for the estimation of unknown parameters and, hence, compared with a broad simulation study. The practicality of the proposed distribution is illustrated in the first-order integer-valued autoregressive process. Its empirical importance is proved through three real datasets.
Reconstruction of a Lower Polar Artery for Kidney Transplantation Using Donor Ovarian Vein: Case Report with Literature Review
Authors: Bikauskaitė Saulė , Počepavičiūtė Kamilė , Velička Linas , Jankauskas Antanas , Trumbeckas Darius , Šuopytė Erika
Published: November 2021

Background: In the case of complicated kidney transplantation, when the accessory artery is severed, the main task is to decide whether to restore renal blood flow and which method should be used. In this report, we present a case of kidney transplantation with vascular reconstruction using an ovarian vein as an interposition graft between a larger branch of the main renal artery and the lower polar artery which was severed during kidney explantation. Case summary: Kidney transplantation using an ovarian vein was performed for a 34-year-old woman with end-stage renal disease on 1 April 2020 in the Hospital of Lithuanian university of health sciences (LUHS) Kaunas Clinics. A lower accessory renal artery was severed during kidney explantation. As the ovarian vein of the donor remained and matched the diameter of the severed vessel, it was decided to use it as an insertion between the main renal artery and the accessory renal artery of the inferior pole. The cold ischemic time was 770 min and the warm ischemic time was 37 min. A month after transplantation, the patient’s condition and daily urine output were normal and the serum creatinine level decreased rapidly. Fifteen months after the surgery, the function and structure of the transplant remained normal and there was no evidence of serious vascular complications on CT scans. This is the first case where graft function was verified after transplantation using three-dimensional CT angiography. Conclusions: If an inferior polar artery is severed, vascular reconstruction must be performed to preserve the function of the graft. Usually, the gonadal vein is available during donor nephrectomy; therefore, it can be explanted without additional difficulties or incisions. Although we have not reported any complications, further studies are recommended on the long-term outcomes of this alternative approach for the reconstruction of short renal arteries.
Acoustic Bessel Vortex Beam by Quasi-Three-Dimensional Reflected Metasurfaces
Authors: Wang Yin , Qian Jiao , Xia Jian-Ping , Ge Yong , Yuan Shou-Qi , Sun Hong-Xiang , Liu Xiao-Jun
Published: November 2021

Vortex beams have a typical characteristic of orbital angular momentum, which provides a new degree of freedom for information processing in remote communication and a form of non-contact manipulation for trapping particles. In acoustics, vortex beams are generally observed on the surface of a metamaterial structure or in a waveguide with a hard boundary owing to the characteristic of easy diffusion in free space. The realization of an acoustic vortex beam with a long-distance propagation in free space still remains a challenge. To overcome this, we report a type of acoustic Bessel vortex (ABV) beam created by a quasi-three-dimensional reflected metasurface in free space based on phase modulation. By using the Bessel and vortex phase profiles, we can realize an ABV beam with the high performances of both Bessel and vortex beams, and its effective propagation distance is larger than 9.2λ in free space. Beyond that, we discuss the bandwidth and topological charge of the ABV beam in detail, and the fractional bandwidth can reach about 0.28. The proposed ABV beam has the advantages of a high-performance vortex, long-distance propagation, and broad bandwidth, which provide a new pathway for designing multifunctional vortex devices with promising applications.
Imbibition of Newtonian Fluids in Paper-like Materials with the Infinitesimal Control Volume Method
Authors: Song Kui , Huang Ruijie , Hu Xiaoling
Published: November 2021

Paper-based microfluidic devices are widely used in point-of-care testing applications. Imbibition study of paper porous media is important for fluid controlling, and then significant to the applications of paper-based microfluidic devices. Here we propose an analytical approach based on the infinitesimal control volume method to study the imbibition of Newtonian fluids in commonly used paper-like materials. Three common paper shapes (rectangular paper strips, fan-shaped and circular paper sheets) are investigated with three modeling methods (corresponding to equivalent tiny pores with circle, square and regular triangle cross section respectively). A model is derived for liquid imbibition in rectangular paper strips, and the control equations for liquid imbibition in fan-shaped and circular paper sheets are also derived. The model is verified by imbibition experiments done using the mixed cellulose ester filter paper and pure water. The relation of imbibition distance and time is similar to that of the Lucas−Washburn (L−W) model. In addition, a new porosity measurement method based on the imbibition in circular paper sheets is proposed and verified. Finally, the flow rates are investigated. This study can provide guidance for the design of different shapes of paper, and for better applications of paper-based microfluidic devices.
2-DOF Small-Size Piezoelectric Locomotion Platform with the Unlimited Motion Range
Authors: Čeponis Andrius , Mažeika Dalius , Jūrėnas Vytautas
Published: November 2021

This paper presents numerical and experimental investigations of a small size piezoelectric locomotion platform that provides unlimited planar motion. The platform consists of three piezoelectric bimorph plates attached to the equilateral triangle-shaped structure by an angle of 60 degrees. Alumina spheres are glued at the bottom of each plate and are used as a contacting element. The planar motion of the platform is generated via excitation of the first bending mode of the corresponding plate using a single harmonic signal while the remaining plates operate as passive supports. The direction of the platform motion controlled by switching electric signal between piezoelectric plates. A numerical investigation of the 2-DOF platform was performed, and it was found out that the operation frequency of the bimorph plates is 23.67 kHz, while harmonic response analysis showed that the maximum displacement amplitude of the contact point reached 563.6 µm in the vertical direction while an excitation signal of 210 Vp-p is applied. Prototype of the 2-DOF piezoelectric platform was made, and an experimental study was performed. The maximum linear velocity of 44.45 mm/s was obtained when preload force and voltage of 0.546 N and 210 Vp-p were applied, respectively.
Microvalve with Trapezoid-Shaped Cross-Section for Deep Microchannels
Authors: Kaminaga Maho , Ishida Tadashi , Omata Toru
Published: November 2021

Simple microfluidic systems for handling large particles such as three-dimensional (3D) cultured cells, microcapsules, and animalcules have contributed to the advancement of biology. However, obtaining a highly integrated microfluidic device for handling large particles is difficult because there are no suitable microvalves for deep microchannels. Therefore, this study proposes a microvalve with a trapezoid-shaped cross-section to close a deep microchannel. The proposed microvalve can close a 350 μm deep microchannel, which is suitable for handling hundreds of micrometer-scale particles. A double-inclined lithography process was used to fabricate the trapezoid-shaped cross-section. The microvalve was fabricated by bonding three polydimethylsiloxane layers: a trapezoid-shaped liquid channel layer, a membrane, and a pneumatic channel layer. The pneumatic balloon, consisting of the membrane and the pneumatic channel, was located beneath a trapezoid-shaped cross-section microchannel. The valve was operated by the application of pneumatic pressure to the pneumatic channel. We experimentally confirmed that the expansion of the pneumatic balloon could close the 350 μm deep microchannel.
Impact of Helicobacter pylori-Related Metabolic Syndrome Parameters on Arterial Hypertension
Authors: Kountouras Jannis , Papaefthymiou Apostolis , Polyzos Stergios A. , Deretzi Georgia , Vardaka Elisabeth , Soteriades Elpidoforos S. , Tzitiridou-Chatzopoulou Maria , Gkolfakis Paraskevas , Karafyllidou Kyriaki , Doulberis Michael
Published: November 2021

Arterial hypertension is a risk factor for several pathologies, mainly including cardio-cerebrovascular diseases, which rank as leading causes of morbidity and mortality worldwide. Arterial hypertension also constitutes a fundamental component of the metabolic syndrome. Helicobacter pylori infection is one of the most common types of chronic infection globally and displays a plethora of both gastric and extragastric effects. Among other entities, Helicobacter pylori has been implicated in the pathogenesis of the metabolic syndrome. Within this review, we illustrate the current state-of-the-art evidence, which may link several components of the Helicobacter pylori-related metabolic syndrome, including non-alcoholic fatty liver disease and arterial hypertension. In particular, current knowledge of how Helicobacter pylori exerts its virulence through dietary, inflammatory and metabolic pathways will be discussed. Although there is still no causative link between these entities, the emerging evidence from both basic and clinical research supports the proposal that several components of the Helicobacter pylori infection-related metabolic syndrome present an important risk factor in the development of arterial hypertension. The triad of Helicobacter pylori infection, the metabolic syndrome, and hypertension represents a crucial worldwide health problem on a pandemic scale with high morbidity and mortality, like COVID-19, thereby requiring awareness and appropriate management on a global scale.