bluuebunny/crossref_metadata_2025 huggingface dataset:
Concurrent Exercise Training: Long-Term Changes in Body Composition and Motives for Continued Participation in Women with Obesity
Authors: Wadsworth Danielle D. , Suire Kameron B. , Peart Ashley , Foote Shelby , Jones Chloe , Rodriguez-Hernandez Mynor , McDonald James R. , Pascoe David D.
Published: December 2022

The purpose of this project was to examine the effect of a concurrent exercise program (sprint interval training and resistance exercise) on body composition in women with obesity and factors associated with continued exercise participation following the program. Twenty women (37.1 ± 7.4 y, height = 1.63 ± 0.09 m, weight = 98.22 ± 0.22 kg, BMI = 34.2 ± 2.50 kg/m2) participated in a 10-week exercise intervention consisting of a sprint interval treadmill protocol and resistance training three times a week totaling 30 sessions. Body composition was measured by dual-energy X-ray absorptiometry (iDXA) at pretest, 12 weeks, and six months post-intervention. Semi-structured interviews assessed participants’ perception of the program at both 12 weeks and six months. Participants significantly reduced fat mass (p < 0.001), gynoid fat mass (p < 0.010), android fat mass (p = 0.003), and visceral fat mass (p = 0.003) at 12 weeks post-test. At six months, participants maintained their reductions in fat mass (p = 0.015), visceral fat (p = 0.040) and gynoid fat mass (p = 0.032). There were no significant main time effects in lean mass (p = 0.099) or caloric intake (p = 0.053) at 12 weeks or six months. Themes that emerged from the semi-structured interviews at 12 weeks reflected enjoyment in the training, increases in competence and knowledge, as well as apprehension of continuing training on their own. At six months, themes that emerged reflected overcoming barriers, competence regarding high-intensity training, and a lack of competence to engage in resistance training. Sprint interval training coupled with resistance training is a feasible exercise protocol for women with obesity and results in reduced fat mass over six months. Improving women’s competence for training is imperative for continued participation.
Experimental Study on the Target–Receiver Formation Problem with the Exploitation of Coherent and Non-Coherent Bearing Information
Authors: Wang Lu , Fang Shiliang , Yang Yixin , Liu Xionghou
Published: December 2022

Localization of emitting sources is a fundamental task in sonar applications. One of the most important factors that affect the localization performance is the sensor–target geometry. The sensor formation problem is usually addressed in related work assuming that the target is static and the location is known to a certain degree, but this is not the case for many underwater surveillance problems. In this paper, we deal with the target–receiver formation problem from a different perspective, and propose to investigate the effect of target–receiver geometry on localization performance by exploiting the spatial spectrum of the direct position determination (DPD) methods. For a given multi-array system, the transformation of geometrical patterns can be explicitly demonstrated as the target moves along the track. Meaningful characteristics of the DPD methods are obtained from the experimental results, where coherent and non-coherent bearing information is used and compared. The feasibility of the DPD approaches in the ocean environments is also investigated by comparing with a matched filter processing (MFP)-based multi-array processor in order to validate the credibility of the results in this paper.
Experimental Performance Analysis of a Hybrid Wave Energy Harvesting System Combining E-Motions with Triboelectric Nanogenerators
Authors: Clemente Daniel , Rodrigues Cátia , Esteves Ricardo , Correia José , Pereira André M. , Ventura João O. , Rosa-Santos Paulo , Taveira-Pinto Francisco , Martins Paulo
Published: December 2022

This paper discusses a disruptive approach to wave energy conversion, based on a hybrid solution: the E-Motions wave energy converter with integrated triboelectric nanogenerators. To demonstrate it, a physical modelling study was carried out with nine E-Motions sub-variants, which were based on three original hull designs (half-cylinder (HC), half-sphere (HS) and trapezoidal prism (TP)). A unidirectional lateral tribo-device was incorporated within the E-Motions’ hull during the experiments. The physical models were subjected to eight irregular sea-states from a reference study on the Portuguese coastline. Results point towards a significant hydrodynamic roll response, with peaks of up to 40 °/m. Three peaks were observed for the surge motions, associated with slow drifting at low frequencies. The response bandwidth of the HC sub-variants was affected by the varying PTO mass-damping values. By comparison, such response was generally maintained for all HS sub-variants and improved for the TP sub-variants, due to ballast positioning adjustments. Maximum power ratios ranged between 0.015 kW/m3 and 0.030 kW/m3. The TENGs demonstrated an average open-circuit voltage and power per kilogram ratio of up to 85 V and 18 mW/kg, respectively, whilst exhibiting an evolution highly dependent upon wave excitation, surge excursions and roll oscillations. Thus, TENGs enable redundant dual-mode wave energy conversion alongside E-Motions, which can power supporting equipment with negligible influence on platform hydrodynamics.
Innovation in Smart Ports: Future Directions of Digitalization in Container Ports
Authors: Heikkilä Marikka , Saarni Jouni , Saurama Antti
Published: December 2022

New digital Industry 4.0 solutions and smart applications are being adopted in many industries, also in the most advanced ports in the world. Still, it is not clear in which directions digitalization in ports will develop in the future. Building on the research literature and the state-of-the-art in major container ports, this research characterizes smart ports and Port 4.0 with three key focus areas: automation, sustainability and collaboration. Following the scenario building theory, this article constructs four alternative scenarios for future smart ports and shows the ways in which these alternative scenarios will lead to different prioritization of digital innovations between automation, sustainable development and cooperation issues. This will have a big impact on what digitalization in ports will be like in the future.
Characteristics and Driving Mechanisms of Salinity Stratification during the Wet Season in the Pearl River Estuary, China
Authors: Yang Fang , Ji Xiaomei , Zhang Wei , Zou Huazhi , Jiang Wenzhi , Xu Yanwen
Published: December 2022

In an estuary, stratification processes play a major role in inhibiting estuarine circulation, sediment transport, and the estuarine ecosystem. A detailed examination of the salinity stratification through the gradient Richardson number and the potential energy anomaly equation has been undertaken along the West Channel of the Pearl River Estuary, China. The results show that the estuarine circulation within the West Channel is much weaker on a spring tide than that on a neap tide, exhibiting apparent spring–neap tidal variability. The calculated gradient Richardson number displays its intratidal and spring–neap tidal variability within the West Channel, indicating the existence of intratidal and spring–neap tidal variability of stratification. In addition, the tidally averaged change rate of total potential energy anomaly within the West Channel suggests more than a 4.53 × 10−3 W·m−3 increase from spring to neap tides, demonstrating strong stratification on a neap tide. The longitudinal advection and the longitudinal depth-mean straining are the leading physical mechanisms contributing to intratidal and spring–neap variability of salinity stratification within the West Channel. However, the effects of the lateral terms cannot be ignored especially on a neap tide.
The Effect of Data Skewness on the LSTM-Based Mooring Load Prediction Model
Authors: Chen Hangyu , Bu Yinglei , Zong Kun , Huang Limin , Hao Wei
Published: December 2022

The working condition of the floating platform will be affected by wind and waves in the marine environment. Therefore, it is of great importance to carry out real-time prediction research on the mooring load for ensuring the normal operation of the floating platform. Current researches have focused on the real-time prediction of mooring load using the machine learning method, but most of the studies are about the application and generalization analysis of different models. There are few studies on the influence of data distribution characteristics on prediction accuracy. In view of the above problems, this paper investigates the effect of data skewness on the prediction performance for the deep learning model. The long short-term memory (LSTM) neural network is applied to construct the mooring load prediction model. The numerical simulation datasets of the deep water semi-submersible platform are employed in model training and data analysis. The prediction performance of the model is preliminarily verified based on the simulation results. Meanwhile, the distribution characteristics of mooring load data under different sea states are analyzed and a skewness processing method based on the Box-Cox Transformation (BCT) is proposed. The effect of data skewness on prediction accuracy is further investigated. The comparison results indicate that reducing the mooring load data skewness can effectively improve the prediction accuracy of LSTM model.
The POSEIDON Ocean Observing System: Technological Development and Challenges
Authors: Ntoumas Manolis , Perivoliotis Leonidas , Petihakis George , Korres Gerasimos , Frangoulis Constantin , Ballas Dionysios , Pagonis Paris , Sotiropoulou Maria , Pettas Manolis , Bourma Evi , Christodoulaki Sylvia , Kassis Dimitris , Zisis Nikos , Michelinakis Spyros , Denaxa Dimitra , Moira Antigoni , Mavroudi Aspasia , Anastasopoulou Gerasimi , Papapostolou Athanasia , Oikonomou Charikleia , Stamataki Natalia
Published: December 2022

Advanced marine observation infrastructures are the most significant scientific tool for the study of marine ecosystem trends and shifts. Ocean monitoring technologies, though highly demanding and expensive, are essential for the monitoring and long-term study of oceanic systems. The POSEIDON system for monitoring and forecasting the marine environment is an augmented research infrastructure, unique in the Eastern Mediterranean basin, contributing to the European Ocean Observing System implementation, focusing—among others—on biogeochemical observations and deep-sea ecosystem and geological processes. The technological evolution of the POSEIDON system through a science-coupled strategy supported by engineers and scientists, resulted in a state-of-the-art ocean observing system. There has been a continuous expansion of the infrastructure with new scientific platforms and supporting facilities. Innovative sensing technologies were introduced in the operational data acquisition and new methodologies and tools were developed to improve the system operations and efficiency. As a part of the scientific community of ocean observatories, POSEIDON contributes actively to the improving of the ocean observing. International access to engineering and field demonstrating services, data products and technology testing facilities has been offered to scientists and industry partners. POSEIDON is a widely recognizable international technology testing/demonstrating node specializing in marine technology providing high-level services.
Stability Characteristics of Horizontal Wells in the Exploitation of Hydrate-Bearing Clayey-Silt Sediments
Authors: Sun Xiaofeng , Hu Qiaobo , Li Yanlong , Chen Mingtao , Zhang Yajuan
Published: December 2022

The mechanical properties of hydrate-bearing strata in clayey-silt sediments are significantly different from those of either conventional reservoirs or hydrate-bearing sandy sediments, which poses great challenges for wellbore stability analyses. The stability characteristics of a deviated borehole during drilling in hydrate-bearing clayey-silt sediments (HBS-CS) remain to be studied. In this paper, an analysis of the wellbore stability characteristics of a deviated borehole using the Mohr–Coulomb (M-C) criterion and Drucker–Prager (D-P) criterion was carried out based on the elastic stress distribution model of the surrounding strata of the wellbore and the triaxial shear tests of the HBS-CS. The results imply that the collapse pressure and safety density window are symmetrically distributed with deviation angle and azimuth. Considering the effect of hydrate decomposition, the collapse pressure gradient could become higher and the instability risks would be amplified. Considering the combined effects of collapse, fracture pressure gradient, and the safety density window, it is suggested that the borehole be arranged along an azimuth of 60–120°, which could greatly reduce the risk in a drilling operation.
Diversity of Circulating NKT Cells in Defense against Carbapenem-Resistant Klebsiella Pneumoniae Infection
Authors: Wang Yidi , Zang Feng , Ye Xiangyu , Li Zhanjie , Zhu Wenhao , Cao Xiaoxiao , Cai Xuehong , Ma Xinyan , Xu Lei , Zhang Yongxiang , Bi Liqing , Yu Rongbin , Huang Peng
Published: December 2022

Nosocomial infection caused by carbapenem-resistant Klebsiella pneumonia (CRKP) infection has become a global public health problem. Human NK and NKT cells in peripheral immune responses are recognized as occupying a critical role in anti-bacterial immunity. Through performed scRNA-seq on serial peripheral blood samples from 3 patients with CRKP undergoing colonization, infection, and recovery conditions, we were able to described the immune responses of NK and NKT cells during CRKP infection and identified a mechanism that could contribute to CRKP clearance. The central player of CRKP infection process appears to be the NKT subset and CD56hiNKT subset which maintained immune competence during CRKP colonization. With time, CRKP leads to the loss of NK and CD160hiNKT cells in peripheral blood, resulting in suppressed immune responses and increased susceptibility to opportunistic infection. In summary, our study identified a possible mechanism for the CRKP invasion and to decipher the clues behind the host immune response that influences CRKP infection pathogenesis.
The Effect of Managerial Myopia on the Adjustment Speed of the Company’s Financial Leverage towards the Optimal Leverage
Authors: Rostami Vahab , Kargar Hamed , Samimifard Mahdis
Published: December 2022

The adjustment speed of financial leverage indicates the movement of companies towards the optimal capital structure, and clearly shows the financing policies of companies. The importance of optimal leverage is such that the growth and survival of companies depend on this factor. This study investigates the effect of managers’ myopia on the adjustment speed of financial leverage toward optimal leverage. The current research is applied, and from the methodological point of view, the correlation is a causal type (retrospective). The statistical population of the research includes all the companies admitted to the Tehran Stock Exchange between 2011 and 2020, and using the systematic elimination sampling method, 124 companies were selected as the research sample. The research results showed that the myopia of managers has an opposite effect on the adjustment speed of financial leverage, so in companies with myopic managers, the adjustment speed of financial leverage decreases towards optimal leverage.
Financial Literacy Levels among Saudi Citizens across Budgeting, Saving, Investment, Debt, and Insurance Dimensions
Authors: Al Rahahleh Naseem
Published: December 2022

This paper provides a comprehensive account of financial literacy among Saudi citizens. Responses to items about key aspects of financial literacy—i.e., budgeting, debt, saving, investment, and insurance—were elicited from a large sample of Saudi citizens through an online survey. The data from 887 completed surveys were subjected to a descriptive analysis, a T-test, and ANOVA. A high level of financial literacy was found among the respondents in relation to budgeting, debt, and saving, but only a moderate level in relation to investment and insurance. The study findings indicate that current efforts on the part of government agencies, schools, universities, and financial institutions focused on budgeting, debt, and saving should continue and that more attention should be paid to educating Saudi citizens in relation to investment and insurance.
Old but Resilient Story: Impact of Decentralization on Social Welfare
Authors: Delgado José Luis Alberto , Demirbaş Dilek , Aysan Ahmet Faruk
Published: December 2022

This paper analyzes the fiscal performance of Turkey and Argentina during the period 2000–2021, when both countries faced rapid economic growth with the consequent impact on social welfare. This work explored two different systems: Centralization in Turkey and Federalism in Argentina and, in general, studied the decentralization impact of both the systems on social welfare. This study intended to create new social welfare indexes in other regions to analyze the resource allocation in different regions of these countries. As a first step, we built a regional human development index (HDI) for each region. This attempt is considered a new contribution to the literature and intended to fill the gap in this field. Afterward, this index was compared with the fiscal resources allocation (FRA), used as a proxy of fiscal decentralization in an econometric panel data model. By using this method, we concluded that the social welfare indexes have a positive relationship with the fiscal resource allocation in the Federal system, such as in Argentina, but not in the centralized system such as in Turkey during the period analyzed from 2000 to 2020.
The Role of ERM and Corporate Governance in Managing COVID-19 Impacts: SMEs Perspective
Authors: Wieczorek-Kosmala Monika , Henschel Thomas
Published: December 2022

SMEs are perceived as more exposed to the consequences of external shocks. The purpose of our work is to examine whether the ERM sophistication or corporate governance mechanisms could be relevant in resistance to COVID-19 shock in the SMEs. In particular, we hypothesize that the SMEs with greater degree of ERM sophistication and stronger CG mechanisms will have a clearer understanding about the severity of the impacts from COVID-19. Our empirical evidence is based on the results of a survey conducted within a large sample of SMEs operating in Poland and in Germany within different experimental settings. We have found that the ERM and CG sophistication influence the perception of COVID-19 interruptions and will alert companies to adjust their business strategy and organizational structure to better cope with effects of the current crisis. The proposed framework can also be a valuable tool for consultants to use to enhance the ERM systems in SMEs.
Estimating the Risk of Financial Distress Using a Multi-Layered Governance Criterion: Insights from Middle Eastern and North African Banks
Authors: Gerged Ali Meftah , Marie Mohamed , Elbendary Israa
Published: December 2022

In this study, we explored the association of bank-level governance and state-level governance with the likelihood of banks’ financial distress in developing economies. Using a panel data sample of 954 bank-year observations of 106 conventional banks across 14 Middle Eastern and North African (MENA) countries from 2010 to 2018, we found that bank governance arrangements seemed to be negatively attributed to the probability of financial distress. We also found that the relationship of political stability with financial distress prospects is—contrary to our expectation—insignificant, whereas government effectiveness negatively influences the likelihood of financial distress. Our empirical evidence offers practical implications for bank managers, regulators, and credit rating agencies, and suggests several future research avenues that can build on our findings.
Assessing Uncertainties in Climate Change Adaptation and Land Management
Authors: Leal Filho Walter , Stojanov Robert , Wolf Franziska , Matandirotya Newton R. , Ploberger Christian , Ayal Desalegn Y. , Azam Fardous Mohammad Safiul , AL-Ahdal Tareq Mohammed Ali , Sarku Rebecca , Tchouaffe Tchiadje Norbert François , Manolas Evangelos , Li Chunlan
Published: December 2022

The entire cascade of scenario generation, global and regional climate modeling, as well as concrete measures towards climate adaptation are subject to uncertainties. An exact prediction of how the climate will change in the coming years, and how it will affect land use, is not possible. There is thus a perceived need to identify ways via which uncertainties can be addressed. Based on the need to address the research gap in this area, this paper reports the findings of a study on uncertainty in a climate change adaptation context, and how it is perceived. It consists of a multi-stakeholder survey among climate change professionals, including academic staff at universities, representatives from international agencies, members of NGOs, policymakers, and representatives of industry from 50 countries, including a balanced representation of industrialized and developing nations. The results obtained suggest that uncertainties are often a hindrance to engagement in climate change adaptation efforts, and to land management. Furthermore, there is a range of tools to reduce climate change adaptation uncertainties, whose deployment may help to address them. The paper concludes by providing a list of lessons learned and suggestions as to how uncertainty can be better communicated, and by doing so, how a reduction in the levels of climate change vulnerability may be achieved, and how land management may be fostered.
Multi-Temporal Analysis of Past and Future Land-Cover Changes of the Third Pole
Authors: Lamchin Munkhnasan , Lee Woo-Kyun , Wang Sonam Wangyel
Published: December 2022

In the past few decades, both natural and human influences have contributed to the unpredictable rates of land use and land-cover change (LUCC) in glacially devastated places. Monitoring and identifying the geographic and temporal land-cover changes and driving forces in this unique type of area may help to give the scientific basis needed to understand the effects of climate change and human activities on LUCC. The Third Pole is one such landscape that provides inevitable key ecosystem services to over 2 billion people in Asia. However, this important landscape is increasingly being threatened by the impacts of climate change. Policy and program responses to the Third Pole’s mounting socioeconomic challenges are inadequate and lack scientific evidence. Using the land-change model (LCM) and historical data from 1992 onwards, our study attempted to (i) detect the spatial patterns of land use and land-cover changes in the Third Pole from 1992 to 2020; and (ii) project them into 2060. Our analysis shows that the land use and land-cover types in the Third pole are undergoing changes. About 0.07% of the snow and ice have melted in the last three decades, indicating global warming. This melt has resulted in increasing water bodies (0.08%), especially as glacial lakes. This has significantly increased the risk of glacial outburst floods. Other key alpine land-cover types that decreased are bare land (0.6%) and agricultural land (0.05%). These land types represent important habitats for wild flora and fauna, grazing land for livestock, and food for nomads, and their loss will directly degrade ecological services and the health and wellbeing of the nomads. Land cover of forest, shrubs, and scanty vegetation have all increased by 0.3%, 0.02%, and 0.77%, respectively, inducing socio-ecological changes in the Third pole mountains. Further predication analysis showed that snow and ice, along with bare land, will continue to recede whereas forest, grassland, water bodies, shrubland, sparse vegetation, and settlement will increase. These results indicate the increasing impact of global warming that will continue to change the Third Pole. These changes have serious implications for designing adaptation and mitigation interventions in the mountains. We recommend more detailed research to investigate the underlying factors that are changing the Third Pole to develop policy and programs to help humans, livestock, and biodiversity adapt to the changes in these remote and harsh mountains. This will also help to mitigate the effects on downstream communities.
The Interplay of Emotions, Executive Functions, Memory and Language: Challenges for Refugee Children
Authors: Franck Julie , Delage Hélène
Published: December 2022

Refugee children tend to show low emotional well-being and weak executive functions that may have consequences on language and therefore complicate a potential diagnosis of Developmental Language Disorder (DLD) in this population. We assessed the performance of 140 children living in Switzerland aged 5 to 8 (20 monolinguals, 86 non-refugee bilinguals, 34 refugee bilinguals) on LITMUS language tasks (nonword repetition, sentence repetition, parental questionnaire), standardized language tasks, memory and executive function tasks. Parents also filled in the Child Behavior Checklist providing a measure of their child’s emotional well-being. Results indicate that refugee children are more emotionally vulnerable and show weaker performance in memory and executive functions tasks compared to non-refugee children, in line with the existing literature. Moreover, when compared to non-refugee bilingual children with similar length of exposure to French, refugee children are disadvantaged on all language tasks. Whereas emotional well-being does not predict language performance, memory and executive functions show up as predictors of both LITMUS and standardized language tasks, although in an unsystematic way. It is concluded that refugee children are at risk across the board and that a better understanding of the complex interplay between well-being, executive functions, memory and language is needed in order to build more appropriate diagnostic tools for these children.
GABAergic Neurotransmission in Human Tissues Is Modulated by Cannabidiol
Authors: Ruffolo Gabriele , Gaeta Alessandro , Cannata Beatrice , Pinzaglia Camilla , Aronica Eleonora , Morano Alessandra , Cifelli Pierangelo , Palma Eleonora
Published: December 2022

Recently, the potential use of phytocannabinoids (pCBs) to treat different pathological conditions has attracted great attention in the scientific community. Among the different pCBs, cannabidiol (CBD) has showed interesting biological properties, making it a promising molecule with a high security profile that has been approved for treatment as an add-on therapy in patients afflicted by severe pharmaco-resistant epilepsy, including Dravet syndrome (DS), Lennox–Gastaut syndrome (LGS) and tuberous sclerosis complex (TSC). CBD is pharmacologically considered a “dirty drug”, since it has the capacity to bind different targets and to activate several cellular pathways. GABAergic impairment is one of the key processes during the epileptogenesis period able to induce a generalized hyperexcitability of the central nervous system (CNS), leading to epileptic seizures. Here, by using the microtransplantation of human brain membranes approach in Xenopus oocytes and electrophysiological recordings, we confirm the ability of CBD to modulate GABAergic neurotransmission in human cerebral tissues obtained from patients afflicted by different forms of pharmaco-resistant epilepsies, such as DS, TSC, focal cortical dysplasia (FCD) type IIb and temporal lobe epilepsy (TLE). Furthermore, using cDNAs encoding for human GABAA receptor subunits, we found that α1β2 receptors are still affected by CBD, while classical benzodiazepine lost its efficacy as expected.
Photosensitivity of Different Nanodiamond–PMO Nanoparticles in Two-Photon-Excited Photodynamic Therapy
Authors: Bondon Nicolas , Durand Denis , Hadj-Kaddour Kamel , Ali Lamiaa M. A. , Boukherroub Rabah , Bettache Nadir , Gary-Bobo Magali , Raehm Laurence , Durand Jean-Olivier , Nguyen Christophe , Charnay Clarence
Published: December 2022

Background: In addition to their great optical properties, nanodiamonds (NDs) have recently proved useful for two-photon-excited photodynamic therapy (TPE-PDT) applications. Indeed, they are able to produce reactive oxygen species (ROS) directly upon two-photon excitation but not with one-photon excitation; Methods: Fluorescent NDs (FNDs) with a 100 nm diameter and detonation NDs (DNDs) of 30 nm were compared. In order to use the gems for cancer-cell theranostics, they were encapsulated in a bis(triethoxysilyl)ethylene-based (ENE) periodic mesoporous organosilica (PMO) shell, and the surface of the formed nanoparticles (NPs) was modified by the direct grafting of polyethylene glycol (PEG) and amino groups using PEG-hexyltriethoxysilane and aminoundecyltriethoxysilane during the sol–gel process. The NPs’ phototoxicity and interaction with MDA-MB-231 breast cancer cells were evaluated afterwards; Results: Transmission electronic microscopy images showed the formation of core–shell NPs. Infrared spectra and zeta-potential measurements confirmed the grafting of PEG and NH2 groups. The encapsulation of the NDs allowed for the imaging of cancer cells with NDs and for the performance of TPE-PDT of MDA-MB-231 cancer cells with significant mortality. Conclusions: Multifunctional ND@PMO core–shell nanosystems were successfully prepared. The NPs demonstrated high biocompatibility and TPE-PDT efficiency in vitro in the cancer cell model. Such systems hold good potential for two-photon-excited PDT applications.
Effects of Taxifolin in Spontaneously Hypertensive Rats with a Focus on Erythrocyte Quality
Authors: Jasenovec Tomas , Radosinska Dominika , Kollarova Marta , Balis Peter , Zorad Stefan , Vrbjar Norbert , Bernatova Iveta , Cacanyiova Sona , Tothova Lubomira , Radosinska Jana
Published: December 2022

Oxidative stress and multiple erythrocyte abnormalities have been observed in hypertension. We focused on the effects of angiotensin-converting enzyme 2 (ACE2) inhibition by MLN-4760 inhibitor on angiotensin peptides, oxidative stress parameters, and selected erythrocyte quality markers in spontaneously hypertensive rats (SHR). We also investigated the potential effects of polyphenolic antioxidant taxifolin when applied in vivo and in vitro following its incubation with erythrocytes. SHRs were divided into four groups: control, taxifolin-treated, MLN-4760-treated, and MLN-4760 with taxifolin. MLN-4760 administration increased the blood pressure rise independent of taxifolin treatment, whereas taxifolin decreased it in control SHRs. Body weight gain was also higher in ACE2-inhibited animals and normalized after taxifolin treatment. However, taxifolin did not induce any change in angiotensin peptide concentrations nor a clear antioxidant effect. We documented an increase in Na,K-ATPase enzyme activity in erythrocyte membranes of ACE2-inhibited SHRs after taxifolin treatment. In conclusion, ACE2 inhibition deteriorated some selected RBC properties in SHRs. Although taxifolin treatment did not improve oxidative stress markers, our data confirmed the blood pressure-lowering potential, anti-obesogenic effect, and some “erythroprotective” effects of this compound in both control and ACE2-inhibited SHRs. In vitro investigations documenting different effects of taxifolin on erythrocyte properties from control and ACE2-inhibited SHRs accentuated the irreplaceability of in vivo studies.
Nonlinear Analytical Procedure for Predicting Debonding of Laminate from Substrate Subjected to Monotonic or Cyclic Load
Authors: Lamberti Marco , Ascione Francesco , Napoli Annalisa , Razaqpur Ghani , Realfonzo Roberto
Published: December 2022

The bonding of steel/fiber-reinforced polymer (SRP/FRP) laminate strips to concrete/masonry elements has been found to be an effective and efficient technology for improving the elements’ strength and stiffness. However, premature laminate–substrate debonding is commonly observed in laboratory tests, which prevents the laminate from reaching its ultimate strength, and this creates uncertainty with respect to the level of strengthening that can be achieved. Therefore, for the safe and effective application of this technology, a close estimate of the debonding load is necessary. Towards this end, in this paper, a new, relatively simple, semi-analytic model is presented to determine the debonding load and the laminate stress and deformation, as well as the interfacial slip, for concrete substrates bonded to SRP/FRP and subjected to monotonic or cyclic loading. In the model, a bond-slip law with a linearly softening branch is combined with an elasto-plastic stress-strain relationship for SRP. The model results are compared with available experimental data from single-lap shear tests, with good agreement between them.
Evaluation of Thermophysical and Mechanical Properties of Sandstone Due to High-Temperature
Authors: Dong Zhen , Chen Yanpeng , Wang Xinggang , Kong Lingfeng , Wang Lianguo , Li Xinning , Sun Fenjin , Ding Ke , Wu Hanqi , Chen Shanshan , Zhang Mengyuan
Published: December 2022

In this study, thermophysical and mechanical tests were conducted on sandstone samples from room temperature to 1000 °C. Based on the test results, the thermophysical properties (such as specific heat capacity, thermal conductivity, and thermal expansion coefficient) of sandstone after high-temperature treatment and the variations of mechanical properties (including peak strength, peak strain, elastic modulus, and whole stress-strain curve) with temperature were analyzed. Indeed, the deterioration law of sandstone after high-temperature treatment was also explored with the aid of a scanning electron microscope (SEM). The results show that with the increase in temperature, the specific heat capacity and thermal expansion coefficient of sandstone samples after high-temperature treatment increase first and then decrease, while the thermal conductivity gradually decreases. The range from room temperature to 1000 °C witnesses the following changes: As temperature rises, the peak strength of sandstone rises initially and falls subsequently; the elastic modulus drops; the peak strain increases at an accelerated rate. Temperature change has a significant effect on the deterioration rules of sandstone, and the increase in temperature contributes to the transition in the failure mode of sandstone from brittle failure to ductile failure. The experimental study on the thermophysical and mechanical properties of sandstone under the action of high temperature and overburden pressure has a guiding significance for the site selection and safety evaluation of UCG projects.
Additive Manufactured Magnesium-Based Scaffolds for Tissue Engineering
Authors: Antoniac Iulian , Manescu (Paltanea) Veronica , Paltanea Gheorghe , Antoniac Aurora , Nemoianu Iosif , Petrescu Mircea , Dura Horatiu , Bodog Alin
Published: December 2022

Additive manufacturing (AM) is an important technology that led to a high evolution in the manufacture of personalized implants adapted to the anatomical requirements of patients. Due to a worldwide graft shortage, synthetic scaffolds must be developed. Regarding this aspect, biodegradable materials such as magnesium and its alloys are a possible solution because the second surgery for implant removal is eliminated. Magnesium (Mg) exhibits mechanical properties, which are similar to human bone, biodegradability in human fluids, high biocompatibility, and increased ability to stimulate new bone formation. A current research trend consists of Mg-based scaffold design and manufacture using AM technologies. This review presents the importance of biodegradable implants in treating bone defects, the most used AM methods to produce Mg scaffolds based on powder metallurgy, AM-manufactured implants properties, and in vitro and in vivo analysis. Scaffold properties such as biodegradation, densification, mechanical properties, microstructure, and biocompatibility are presented with examples extracted from the recent literature. The challenges for AM-produced Mg implants by taking into account the available literature are also discussed.
Comparison of Temperature Distribution between TWIP and Plain Carbon Steels during Wire Drawing
Authors: Hwang Joong-Ki
Published: December 2022

The effect of the thermal properties of steels on wire drawing behavior has been investigated to understand and improve the wire drawing process. Finite element analysis and experimental tests were conducted to analyze the temperature distribution of the deformed specimens with different thermal properties. The thermal properties of twinning-induced plasticity (TWIP) steel were measured and compared with those of plain carbon steel. Based on the measurement of thermal properties, wire drawing behaviors were systematically compared with thermal conductivity of the specimen (k) using plain low-carbon steel with high k and TWIP steel with low k. The results revealed that the k of TWIP steel was approximately one third of that of low-carbon steel, and the thermal expansion coefficient of the TWIP steel was approximately 50% higher than that of low-carbon steel in the temperature range of 26–400 °C. The temperature distributions in the wire strongly depended on the k of the wire during wire drawing. TWIP steel exhibited higher maximum temperature, and took a longer time to attain the equilibrium temperature than low-carbon steel during wire drawing owing to the low k. The maximum temperature of the die increased with decreasing k of the wire, indicating that die wear can increase with decreasing k of the wire. Therefore, reducing the drawing speed is suggested for a wire with low k, such as high-alloyed metals, especially for TWIP steels.
Hydrogen Recovery from Waste Aluminum–Plastic Composites Treated with Alkaline Solution
Authors: Buryakovskaya Olesya A. , Vlaskin Mikhail S.
Published: December 2022

An alternative solution to the problem of aluminum–plastic multilayer waste utilization was suggested. The process can be used for hydrogen generation and layer separation. Three different sorts of aluminum–plastic sandwich materials were treated with an alkali solution. In the temperature range of 50–70 °C, for tablet blisters of polyvinylchloride and aluminum (14.8 wt.%), the latter thoroughly reacted in 15–30 min. For sheets of paper, polyethylene, and aluminum (20 wt.%), full hydrogen ‘recovery’ from reacted aluminum component took 3–8 min. From the lids of polyethylene terephthalate, aluminum (60 wt.%), and painted polyethylene with perforations, the aluminum was consumed after 45–105 min. The effect of perforations was the reduction of the process duration from nearly 90 min for the lids with no perforations to nearly 45 min for the perforated ones (at 70 °C). Perforations provided better contact between the aluminum foil, isolated between the plastic layers, and the alkali solution. Hydrogen bubbles originating near those perforations provided foil separation from the upper painted plastic layer by creating gas gaps between them. The remaining components of the composite multilayer materials were separated and ready for further recycling.
Impact of Thermophysical Properties of High-Alloy Tool Steels on Their Performance in Re-Purposing Applications
Authors: Berger Aaron , Benito Santiago , Kronenberg Philipp , Weber Sebastian
Published: December 2022

Resource efficiency and circularity in the context of sustainability are rapidly gaining importance in the steel industry. One concept regarding circular economy is “repurposing”. In the context of this work, worn-out machine circular knives are used to produce new chisels for woodturning. The chisels can be extracted parallel or perpendicular to the rolling direction of the primary production process, resulting in an associated carbide orientation of the repurposed tool. The rolling direction, and therefore carbide alignment, will influence the wear resistance and the thermophysical properties, whereby the thermal conductivity will determine the temperatures at the tip of the chisel. Therefore, the thermal conductivity was investigated with the dynamic measurement method, where the specific heat capacity, density and thermal diffusivity of the extracted chisels and industrial reference chisels were measured separately. Moreover, the electrical resistivity was measured in order to calculate the electronic thermal conductivity according to the Wiedemann–Franz–Lorenz law. It was shown that all of these parameters exhibited different degrees of variability with rising temperature. In a detailed analysis, the thermal diffusivity could be identified as an essential parameter of thermal conductivity. By taking two conventional chisels with different chemical compositions and heat treatments into account, it can be seen that the microstructure determines the thermophysical properties. Considering the carbide direction, the chisels that were extracted parallel to the rolling direction showed differing thermophysical properties. Therefore, the carbide orientation is shown to play a significant role regarding the heat dissipation at the cutting edge, because differences, especially in the electronic thermal conductivity in the parallel and perpendicular extracted chisels, can be measured. In addition to the wear resistance factor, the thermal conductivity factor now also supports the removal of the repurposed chisels parallel to the rolling direction.
Microstructural and Mechanical Characterization of Newly Developed Zn-Mg-CaO Composite
Authors: Pinc Jan , Kubásek Jiří , Drahokoupil Jan , Čapek Jaroslav , Vojtěch Dalibor , Školáková Andrea
Published: December 2022

In this study, the Zn-0.8Mg-0.28CaO wt.% composite was successfully prepared using different conditions of ball milling (rotations and time) followed by a direct extrusion process. These materials were characterized from the point of view of microstructure and compressive properties, and the correlation between those characteristics was found. Microstructures of individual materials possessed differences in grain size, where the grain size decreased with the intensified conditions (milling speed and time). However, the mutual relation between grain size and compressive strength was not linear. This was caused by the effect of other factors, such as texture, intermetallic phases, and pores. Material texture affects the mechanical properties by a different activity ratio between basal and pyramidal  slips. The properties of intermetallic particles and pores were determined in material volume using micro-computed tomography (µCT), enhancing the precision of our assumptions compared with commonly applied methods. Based on that, and the analysis after the compressive tests, we were able to determine the influence of aspect ratio, feret diameters, and volume content of intermetallic phases and pores on mechanical behavior. The influence of the aspects on mechanical behavior is described and discussed.
Application of the LPE-Grown LuAG: Ce Film/YAG Crystal Composite Thermoluminescence Detector for Distinguishing the Components of the Mixed Radiation Field
Authors: Mrozik Anna , Bilski Paweł , Gieszczyk Wojciech , Kłosowski Mariusz , Witkiewicz-Łukaszek Sandra , Gorbenko Vitaliy , Zorenko Tetiana , Zorenko Yuriy
Published: December 2022

Single-crystalline films (SCFs) of the LuAG: Ce garnet grown using the liquid-phase epitaxy method onto YAG single-crystal (SC) substrates were investigated for possible applications as composite thermoluminescent (TL) detectors. Such detectors may help to register the different components of ionizing radiation fields with various penetration depths, e.g., heavy charged particles and gamma or beta rays. It was found that the TL signal of LuAG: Ce SCF sufficiently differs from that of the YAG substrate concerning both the temperature and wavelength of emissions. Furthermore, even by analyzing TL glow curves, it was possible to distinguish the difference between weakly and deeply penetrating types of radiation. Within a test involving the exposure of detectors with the mixed alpha/beta radiations, the doses of both components were determined with an accuracy of a few percent.
Properties of Biochar Derived from Tea Waste as an Alternative Fuel and Its Effect on Phytotoxicity of Seed Germination for Soil Applications
Authors: Tunklová Barbora , Jeníček Lukáš , Malaťák Jan , Neškudla Michal , Velebil Jan , Hnilička František
Published: December 2022

Tea waste as a potential biofuel and bio fertilizer was analyzed. Samples were collected from various tea species and torrefied to five different temperatures. All samples were analyzed for their proximal composition and calorific value. From the results, stoichiometric properties were calculated. A phytotoxicity test was performed, and the germination index was measured. Tea waste torrefied at 350 °C may be suitable biofuel reaching the calorific value of 25–27 MJ kg−1, but with quite a high share of ash, up to 10%, which makes its use technically challenging and may lead to operating issues in a combustion chamber. The same biochar may be a suitable fertilizer for increasing the germination index, therefore, applicable to the soil. The non-torrefied sample and the sample treated at 250 °C are not suitable as fertilizers for being toxic. The total phenolic content in waste black tea was reduced from 41.26 to 0.21 mg g−1, depending on the torrefaction temperature. The total flavonoid content was also reduced from 60.49 to 0.5 mg g−1. The total antioxidant activity in the non-torrefied sample was 144 mg g−1, and after torrefaction at 550 °C, it was 0.82 mg g−1. The results showed that black tea waste residues have the potential for further use, for example, in agriculture as a soil amendment or as a potential biofuel.
Numerical Analysis of Dynamic Properties of an Auxetic Structure with Rotating Squares with Holes
Authors: Mrozek Agata , Strek Tomasz
Published: December 2022

In this paper, a novel auxetic structure with rotating squares with holes is investigated. The unit cell of the structure consists of four units in the shape of a square with cut corners and holes. Finally, the structure represents a kind of modified auxetic structure made of rotating squares with holes or sheets of material with regularly arranged diamond and square cuts. Effective and dynamic properties of these structures depend on geometrical properties of the structure. The structures are characterized by an effective Poisson’s ratio from negative to positive values (from about minus one to about plus one). Numerical analysis is made for different geometrical features of the unit cells. The simulations enabled the determination of the dynamic characteristic of the analyzed structures using vibration transmission loss, transmissibility, and mechanical impedance. Numerical calculations were conducted using the finite element method. In the analyzed cases of cellular auxetic structures, a linear elasticity model of the material is assumed. The dynamic characteristic of modified rotating square structures is strongly dependent not only on frequency. The dynamic behavior could also be enhanced by adjusting the geometric parameter of the structure. Auxetic and non-auxetic structures show different static and dynamic properties. The dynamic properties of the analyzed structures were examined in order to determine the frequency ranges of dynamic loads for which the values of mechanical impedance and transmissibility are appropriate.