bluuebunny/crossref_metadata_2025 huggingface dataset:
A 77-GHz High Gain Low Noise Receiver for Automatic Radar Applications
Authors: Cheng Shuai , Li Linhong , Mei Niansong , Zhang Zhaofeng
Published: June 2021

In this paper, a high gain 77-GHz receiver with a low noise figure (NF) was designed and implemented in a 40-nm CMOS process. With the purpose of making better use of active devices, an extra inductor, Ld, is adopted in the new neutralization technique. The three-stage differential low noise amplifier (LNA) using the proposed technique improves the voltage gain and reduces the NF. The receiver design utilizes an active double-balanced Gilbert mixer with a transformer coupling network between the transconductance stage and the switch stage. The flicker noise contribution from the switch MOS transistors is largely reduced due to the low DC current of the switch pairs. The LO signal is provided by an on-chip fundamental voltage-controlled oscillator (VCO) with a tuning range from 70.5 to 78.1 GHz. A conversion gain of 32 dB and a NF of 11.86 dB are achieved at 77 GHz by the designed receiver. The LNA as well as the mixer consume a total DC power of 33.2 mW and occupy a core size of 1 × 0.38 mm2.
Efficient Directional Antenna Design Suitable for Ubiquitous Power Internet of Things
Authors: Zhao Jingcheng , Chao Xu , Hong Tao , Wang Peng , Zheng Shuli
Published: June 2021

Today’s power systems are developing from traditional multi-sensor systems to ubiquitous power Internet of Things systems. The environmental backscatter technology makes communication equipment get rid of the dependence on power supply, is more energy-efficient, and effectively extends the communication distance, which is very suitable for power Internet of Things scenarios. Tag antenna is an important part of environmental backscattering, but it has problems such as low reliability and insufficient reading distance in the traditional power Internet of Things. In view of the above problems, this paper designs a double-antenna structure tag antenna, which adopts omnidirectional receiving and directional transmitting methods to achieve the purpose of comprehensive signal coverage for the power Internet of Things application scenarios. It has the characteristics of obvious gain, small side lobe, and strong anti-interference.
Noise Efficient Integrated Amplifier Designs for Biomedical Applications
Authors: Simmich Sebastian , Bahr Andreas , Rieger Robert
Published: June 2021

The recording of neural signals with small monolithically integrated amplifiers is of high interest in research as well as in commercial applications, where it is common to acquire 100 or more channels in parallel. This paper reviews the recent developments in low-noise biomedical amplifier design based on CMOS technology, including lateral bipolar devices. Seven major circuit topology categories are identified and analyzed on a per-channel basis in terms of their noise-efficiency factor (NEF), input-referred absolute noise, current consumption, and area. A historical trend towards lower NEF is observed whilst absolute noise power and current consumption exhibit a widespread over more than five orders of magnitude. The performance of lateral bipolar transistors as amplifier input devices is examined by transistor-level simulations and measurements from five different prototype designs fabricated in 180 nm and 350 nm CMOS technology. The lowest measured noise floor is 9.9 nV/√Hz with a 10 µA bias current, which results in a NEF of 1.2.
Bridging the Gap between Academia and Industry through Students’ Contributions to the FIWARE European Open-Source Initiative: A Pilot Study
Authors: Conde Javier , López-Pernas Sonsoles , Pozo Alejandro , Munoz-Arcentales Andres , Huecas Gabriel , Alonso Álvaro
Published: June 2021

Although many courses in computer science and software engineering require students to work on practical assignments, these are usually toy projects that do not come close to real professional developments. As such, recent graduates often fail to meet industry expectations when they first enter the workforce. In view of the gap between graduates’ skills and industry expectations, several institutions have resorted to integrating open-source software development as part of their programs. In this pilot study, we report on the results of the contributions of eleven students to the FIWARE open-source project as part of their final year project. Our findings suggest that both teachers and students have a positive perception towards contributing to the FIWARE open-source initiative and that students increased their knowledge of technologies valued by the industry. We also found that this kind of project requires an additional initial effort for the students as well as for the instructor to monitor their progress. Consequently, it is important that the instructors have previous experience in FIWARE, as many of the students need help during the process.
The Sustainability of Decentralised Renewable Energy Projects in Developing Countries: Learning Lessons from Zambia
Authors: Stritzke Susann , Jain Prem
Published: June 2021

Decentralised renewable energy (RE) systems such as solar PV mini-grids (MG) are considered to be a cornerstone for the strategic achievement of the UN’s energy access goals in the developing world. Many of these systems implemented however face substantial technical, financial and social sustainability challenges which are also a recurring theme in the relevant literature. MG analyses however often lack detailed technical or financial data or apply ‘silo-approaches’ as a comprehensive review of MG case study literature presented in this article reveals. Consequently, this study aims to enhance the understanding of RE MG sustainability in the developing context based on the integrated evaluation of the technical, financial and social dimensions of MG operation through empirical data from community surveys on energy use from Uganda and Zambia and two in-depth MG case studies from Zambia. By presenting detailed technical and financial data in combination with energy consumer perception, the study aims to close existing data gaps on sustainable RE MG operation and offers an approach to evaluate and optimise the operational sustainability of an MG in its individual local context. The article finds that the complex rural community ecosystem is a central, but yet undervalued determinant of MG sustainability in rural developing contexts. The mismatch between energy affordability and MG tariffs threatens MG sustainability and the scaling of energy access projects if not addressed specifically during project development and implementation. Consequently, the article calls for a strategic inclusion of community-ecosystem parameters and MG planning based on realistic energy affordability levels and an added value approach that includes dynamic MG financing mechanisms and targeted measures to generate added value through energy consumption as integral parts of RE MG projects.
A Study on the Shape of the Rotor to Improve the Performance of the Spoke-Type Permanent Magnet Synchronous Motor
Authors: Jeong Min-Jae , Lee Kang-Been , Pyo Hyun-Jo , Nam Dong-Woo , Kim Won-Ho
Published: June 2021

This paper describes a study on the improvement of the dehydration performance of the conventional washing machine model. Recently, as interest in improving the dehydration performance of washing machines has increased, the need for a study on a high-speed electric motor has emerged. However, this conventional spoke-type PMSM has difficulty in speeding up due to the following problems. First, field weakening control is indispensable for high-speed operation of an electric motor. This control method is a big problem in causing torque drop and irreversible demagnetization of the motor. Moreover, the centrifugal force increases during high-speed operation, which adversely affects the stiffness of the motor. Therefore, in this paper, a new rotor shape of spoke-type PMSM was proposed to solve the above problem.
Solar Irradiance Forecast Based on Cloud Movement Prediction
Authors: Radovan Aleksander , Šunde Viktor , Kučak Danijel , Ban Željko
Published: June 2021

Solar energy production based on a photovoltaic system is closely related to solar irradiance. Therefore, the planning of production is based on the prediction of solar irradiance. The optimal use of different energy storage systems requires an accurate prediction of solar irradiation with at least an hourly time horizon. In this work, a solar irradiance prediction method is developed based on the prediction of solar shading by clouds. The method is based on determining the current cloud position and estimating the velocity from a sequence of multiple images taken with a 180-degree wide-angle camera with a resolution of 5 s. The cloud positions for the next hour interval are calculated from the estimated current cloud position and velocity. Based on the cloud position, the percentage of solar overshadowing by clouds is determined, i.e., the solar overshadowing curve for the next hour interval is calculated. The solar irradiance is determined by normalizing the percentage of the solar unshadowing curve to the mean value of the irradiance predicted by the hydrometeorological institute for that hourly interval. Image processing for cloud detection and localization is performed using a computer vision library and the Java programming language. The algorithm developed in this work leads to improved accuracy and resolution of irradiance prediction for the next hour interval. The predicted irradiance curve can be used as a predicted reference for solar energy production in energy storage system optimization.
Topsoil Moisture Depletion and Recharge below Young Norway Spruce, White Birch, and Treeless Gaps at a Mountain-Summit Site
Authors: Špulák Ondřej , Šach František , Kacálek Dušan
Published: June 2021

Background and Objectives: Mineral topsoil moisture is a very important component of the hydrological balance in forests. The moisture is closely related to the forest type, its woody species composition, stand age, and structure through interception and evapotranspiration. We aimed to investigate the topsoil moisture response to precipitation in three treatments: under young Norway spruce, white birch, and a grass-dominated treeless gap at an acidic mountain site in the Jizerské hory Mts., Czech Republic. The study was conducted in 18- to 21-year-old stands during four growing seasons. Materials and Methods: The analyzed parameters were: rainfall amounts measured by an on-site automated station, root penetration using a root auger, and soil moisture measured continuously using electric sensors, as well as derived parameters such as interception. Results and Conclusions: Even within small patches of the three treatments, soil water content was found to be higher under the gap vegetation compared to both tree species. In addition, the topsoil under spruce was significantly more saturated than under birch. The average growing-season interception capacity of birch, spruce, and the gap treatment ranged from 1.4 to 2.2 mm, 2.1 to 2.6 mm, and 1.2 to 2.2 mm, respectively. Soil moisture mostly decreased during periods of flushing and stabilized during the transitions from the growing to the dormant seasons. The seasonal effects were particularly obvious under the birch stand. The crucial factors decreasing topsoil water content under birch included both rooting depth and density, which may predispose preferential pathways for water infiltration. This validated white birch’s capability to decrease topsoil water content, which can be beneficial at secondary-waterlogged sites.
Degenerate Derangement Polynomials and Numbers
Authors: Ma Minyoung , Lim Dongkyu
Published: June 2021

In this paper, we consider a new type of degenerate derangement polynomial and number, which shall be called the degenerate derangement polynomials and numbers of the second kind. These concepts are motivated by Kim et al.’s work on degenerate derangement polynomials and numbers. We investigate some properties of these new degenerate derangement polynomials and numbers and explore their connections with the degenerate gamma distributions for the case λ∈(−1,0). In more detail, we derive their explicit expressions, recurrence relations, and some identities involving our degenerate derangement polynomials and numbers and other special polynomials and numbers, which include the fully degenerate Bell polynomials, the degenerate Fubini polynomials, and the degenerate Stirling numbers of the first and the second kinds. We also show that those polynomials and numbers are connected with the moments of some variants of the degenerate gamma distributions. Moreover, we compare the degenerate derangement polynomials and numbers of the second kind to those of Kim et al.
Diabetes Mellitus—A Risk Factor for Unfavourable Outcome in COVID-19 Patients—The Experience of an Infectious Diseases Regional Hospital
Authors: Miftode Egidia , Miftode Larisa , Coman Ioana , Prepeliuc Cristian , Obreja Maria , Stămăteanu Oana , Părângă Tudorița Gabriela , Leca Daniela , Pleşca Claudia Elena
Published: June 2021

Early research into the implications concerning the evolution of the infection caused by the new coronavirus in people with glucose metabolism dysfunction, in this case diabetics, shows that severe forms of the disease predominate in this risk category. Moreover, it seems that even in patients with normal glycaemic status, COVID-19 may predispose to the development of hyperglycaemia which modulates immune mechanisms and inflammatory responses, with direct effects on morbidity and mortality. Thus, taking into account these scientific data, as well as the increased frequency of diabetes in the general population, we aimed to assess the risk of an unfavourable outcome of diabetic patients, which is in a strong connection with the presence and severity of pulmonary disease such as interstitial pneumonia/bronchopneumonia, as well as the effectiveness of Tocilizumab administration. The results of our study indicate a three-fold higher risk of death in patients with diabetes and COVID-19 (RR = 3.03; IC95%: 2.37–3.86; p = 0.001),compared to nondiabetic patients, and the risk of developing severe forms of acute respiratory failure was 1.5 times higher in the first studied category. In conclusion, we can say that the diabetic diagnosed with SARS-CoV-2 infection is more predisposed to immunological and organic dysfunctions that may ultimately result in death, and treatment with monoclonal anti-IL-6 antibodies was more effective in diabetic patients than non-diabetics (p < 0.05). The effectiveness of Tocilizumab was significant in both studied groups, but diabetic patients responded better to this therapy compared to non-diabetes-mellitus (DM) ones (76.7% vs. 35% p = 0.001).
The Case History of an Insect Infestation Revealed Using X-ray Computed Tomography and Implications for Museum Collections Management Decisions
Authors: Arbat Shivani , Forschler Brian T. , Mondi Annelies M. , Sharma Ajay
Published: June 2021

The protection of cultural heritage and property is a significant and critical task that requires collaboration and expertise in a variety of disciplines. Of the many risk factors, insect infestation is one cause of deterioration and loss. At a large, state university, disparate departments, ranging from Facilities Management to the Entomology Department and Veterinary Medicine, assisted the university museum in identifying a drywood termite infestation, determining the extent of loss and developing a plan to prevent or mitigate future infestations. Our group was able to determine the extent and severity of a drywood termite infestation in the museum storage vault through visual inspection and X-ray computed tomography (CT). This paper describes the process and heuristics of identifying and estimating the amount of active/inactive termite infestations in the art frames as well as visualizing a 3-dimensional structure to learn the extent of infestation. This interdisciplinary collaboration and effectual use of tomography enabled our group to determine the condition of several art frames through non-invasive means and develop a plan of action to identify and prevent future insect incursions within the museum.
Thermal Effects of Topical Hyperbaric Oxygen Therapy in Hard-to-Heal Wounds—A Pilot Study
Authors: Kasprzyk-Kucewicz Teresa , Cholewka Armand , Englisz-Jurgielewicz Beata , Mucha Romualda , Relich Michał , Kawecki Marek , Sieroń Karolina , Onak Patrycja , Stanek Agata
Published: June 2021

Clinical studies have been performed to evaluate the thermal response of topical hyperbaric oxygen therapy (THBOT) in patients suffering from hard-to-heal wounds diagnosed as venous leg ulcers located on their lower extremities. It was found that this therapy leads to a temperature decrease in areas around the wound. Moreover, a minor temperature differentiation between all areas was seen in the third period of topical hyperbaric oxygen therapy (THBOT) that may suggest that microcirculation and thermoregulation improvement start the healing process. On the other hand, the results of the conducted studies seem to prove that thermal imaging may provide a safe and effective method of analyzing wound healing of hard-to-heal wounds being treated with THBOT. This is the first study that tries to show the possibilities of a very new method by evaluating treatment of hard-to-heal wounds using thermal imaging, similar to the hyperbaric oxygen therapy effects evaluated by thermal imaging and described previously. However, the first clinical results showed a decrease in temperature due to the THBOT session and some qualitative similarities in the decrease in temperature differentiation between the studied areas and the temperature effects obtained due to hyperbaric oxygen therapy.
E8-LWDS: Factorial Structure and Psychometric Properties of the Lebanese Waterpipe Dependence Scale-11 in 1490 Egyptian Waterpipe Tobacco Smokers—A Critical Approach
Authors: Mostafa Aya , Ismail Nashwa
Published: June 2021

Introduction: There is no universal scale for assessing waterpipe tobacco (WT) dependence. We examined the factorial structure and psychometric properties of the Waterpipe Dependence Scale-11 (LWDS-11) among Egyptian WT smokers. Methods: We administered the LWDS-11 during face-interview questionnaires in two cross-sectional surveys among 1490 current WT smokers recruited via purposive quota sampling. Exploratory factor analysis was performed on half of the sample. Confirmatory factor analysis of the resulting model was done using structural equation modelling on the other half. Scale reliability was examined. We assessed convergent construct validity using regression models to examine the association between the adapted dependence scale and factors conceptually expected to be associated with WT dependence. Results: Exploratory factor analysis of the scale yielded eight items (E8-LWDS) supporting a three-factor structure: physical dependence (three items); psychological dependence (three items); and psychological craving (two items). Cronbach’s α were 0.635 for the total scale and 0.823, 0.654, and 0.785 for the three subscales. E8-LWDS was confirmed to have good model fit (comparative fit index = 0.995; root mean squared error of approximation = 0.027). E8-LWDS was independently associated with daily WT smoking, rural residence, being a skilled worker, non-exclusive WTS, smoking ≥ eight WT hagars/day, and measures of perceived behavioral control (self-reported addiction to WT, perceived ability to quit, and previous quit attempts). Conclusion: E8-LWDS showed adequate psychometric properties among this sample of Egyptian current WT smokers, which makes it appropriate for use by researchers and practitioners. Adding items related to perceived behavioral control might enhance the scale robustness.
How to Understand the Role of Insurance Mechanism in a Global Pandemic?
Authors: Kong Feng
Published: June 2021

The COVID-19 epidemic has seriously affected global economic and social development. The extent to which insurance can play a role in preventing and transferring the risk of infectious diseases has become one of the major concerns of the community. This paper first analyzes the main contents of the U.S. Pandemic Risk Insurance Act during the COVID-19 epidemic and its insights to the global audiences. Then, on the basis of the definition of global pandemic, this paper analyzes the great challenges faced by the insurability of the infectious diseases’ catastrophe from the regional impact, risk accumulation, correlation with capital markets, and accuracy of catastrophe model, and the insurability of local infectious diseases. Finally, this paper presents the key points of the top-level design of the risk transfer mechanism of infectious disease insurance in China. This paper is informative in understanding the role of insurance in the risk transfer of infectious diseases.
Source and Health Risk Assessment of Heavy Metals in Soil–Ginger System in the Jing River Basin of Shandong Province, North China
Authors: Wang Songtao , Gao Zongjun , Zhang Yuqi , Zhang Hairui , Wu Zhen , Jiang Bing , Liu Yang , Dong Hongzhi
Published: June 2021

This study investigated the characteristics and sources of heavy metals in a soil–ginger system and assessed their health risks. To this end, 321 topsoil samples and eight soil samples from a soil profile, and 18 ginger samples with root–soil were collected from a ginger-planting area in the Jing River Basin. The average concentration of heavy metals in the topsoil followed the order: Cr > Zn > Pb > Ni > Cu > As > Cd > Hg. In the soil profile, at depths greater than 80 cm, the contents of Cr, Ni, and Zn tended to increase with depth, which may be related to the parent materials, whereas As and Cu contents showed little change. In contrast, Pb content decreased sharply from top to bottom, which may be attributable to external environmental and anthropogenic factors. Multivariate statistical analysis showed that Cr, Ni, Cu, Zn, and Cd contents in soil are affected by natural sources, Pb and As contents are significantly affected by human activities, and Hg content is affected by farmland irrigation. Combined results of the single pollution index (Pi), geo-accumulation index (Igeo), and potential ecological risk assessment (Ei and RI) suggest that soil in the study area is generally not polluted by heavy metals. In ginger, Zn content was the highest (2.36 mg/kg) and Hg content was the lowest (0.0015 mg/kg). Based on the bioconcentration factor, Cd and Zn have high potential for enrichment in ginger. With reference to the limit of heavy metals in tubers, Cr content in ginger exceeds the standard in the study area. Although Cr does not accumulate in ginger, Cr enrichment in soil significantly increases the risk of excessive Cr content in ginger.
Do Deterrence Mechanisms Reduce Cyberloafing When It Is an Observed Workplace Norm? A Moderated Mediation Model
Authors: Song Mengmeng , Ugrin Joseph , Li Man , Wu Jinnan , Guo Shanshan , Zhang Wenpei
Published: June 2021

Despite the documented individual, job, and organizational antecedents of cyberloafing at the workplace, few studies have addressed whether, how and when group factors affect employees’ cyberloafing behaviors. Drawing on social learning theory and general deterrence theory, the purpose of this study is to test if observability of coworkers’ cyberloafing behavior affects employees’ perceptions of norms related to cyberloafing and subsequent cyberloafing behaviors and to test if sanctions can play a role in buffering these effects. An investigation of 335 employees working at Chinese enterprises establishes that observing others engaging in cyberloafing influences the employees’ perceived norms and cyberloafing behaviors and that employees’ perceived norms related to cyberloafing play a partial mediating role in the relationship between observability and employees’ cyberloafing. As predicted, we also found that perceived certainty and severity of potential sanctions for cyberloafing moderate the effect of observability on employees’ cyberloafing as well as the indirect effect of observability on employees’ cyberloafing via perceived norms related to cyberloafing. This study enriched the cyberloafing literature by revealing how observability of cyberloafing influences employees’ cyberloafing and by unveiling two boundary conditions under which the cyberloafing learning effect can be buffered.
Approaches for Disseminating Environmental Research Findings to Navajo Communities
Authors: Rock Tommy , Jones Lindsey , Ingram Jani C.
Published: June 2021

We report the use of three different dissemination approaches for providing environmental research results back to Navajo communities from different research projects. The objectives of the dissemination are to provide the results to the community, have a dialogue about the results, and learn more about the environmental concerns of the community for potential future research projects. The first approach utilizes radio announcements and flyers provided to the community announcing dissemination meetings specific to the research projects. The second approach is more collaborative, working with a grassroots organization to organize report-back meetings, as well as one-on-one discussions of the research project. The third approach involves the development of a booklet for distribution to communities along with an oral presentation at the regularly scheduled monthly community meetings to discuss the information. Overall, the second and third approaches are more effective than the first approach in terms of dissemination to a larger number of community members, as well as increased dialogue between the researchers and the communities.
Tobacco Use Status and Temptation to Try E-Cigarettes among a Sample of Appalachian Youth
Authors: Mattingly Delvon T. , Rai Jayesh , Agbonlahor Osayande , Walker Kandi L. , Hart Joy L.
Published: June 2021

E-cigarettes are commonly used tobacco products among youth populations, including Appalachian youth. However, knowledge of the extent to which tobacco use status relates to temptation to try e-cigarettes is limited. Data from the Youth Appalachian Tobacco Study (n = 1047) were used. Temptation to try e-cigarettes was derived from a 12-item situational inventory. Tobacco use status was defined as never, ever non-e-cigarette, and ever e-cigarette use. A factorial ANOVA was used to estimate the adjusted association between tobacco use status and the e-cigarette use temptation scale. Two-way interaction terms between tobacco use status and gender, and tobacco use status and race/ethnicity, were plotted to depict effect modification. Approximately 10% of youth were ever non-e-cigarette users and 24% were ever e-cigarette users. Never and ever non-e-cigarette user middle schoolers had higher temptation to try e-cigarettes than their high school counterparts. The same relationship was found among never and ever e-cigarette users living in households with tobacco users. The ANOVA results suggest a positive, monotonic relationship between tobacco use status and temptation to try e-cigarettes, and that the adjusted group means differ by gender and race/ethnicity. The findings can inform tobacco prevention interventions for youth at higher risk for e-cigarette use, especially youth who have not yet tried e-cigarettes.
Mine Water for the Generation and Storage of Renewable Energy: A Hybrid Hydro–Wind System
Authors: Álvarez Héctor , Domínguez Guillermo , Ordóñez Almudena , Menéndez Javier , Álvarez Rodrigo , Loredo Jorge
Published: June 2021

Mine water is normally considered as waste that has to be managed. However, new applications are increasingly being sought for the water that floods mining voids, especially in relation to its use as an energy resource. The worldwide energy market, within the current transition framework, is searching for creative approaches to produce and store clean energy. In particular, underground pumped hydroelectric energy storage systems (UPHS) constitute efficient and flexible alternatives to deal with intermittent renewable energy sources. In this work, a UPHS is designed using the mine water and the voids of a closed coal mine in Asturias (North-west Spain) as a lower reservoir. Moreover, this system is combined with a wind energy generation facility and the efficiency of the hybrid system is evaluated. With an investment cost of EUR 193 M, a 40 MW UPHES joined to a 60 MW wind farm would generate benefits of about EUR 54 M in 40 years. The reduction in CO2 emissions (29,000 equivalent tons per year) and the social benefits in a traditional mining area are other intangible advantages of this system.
Effects of 16 Weeks of Resistance Training on Muscle Quality and Muscle Growth Factors in Older Adult Women with Sarcopenia: A Randomized Controlled Trial
Authors: Seo Myong-Won , Jung Sung-Woo , Kim Sung-Woo , Lee Jung-Min , Jung Hyun Chul , Song Jong-Kook
Published: June 2021

This study examined the effects of resistance training on muscle quality, muscle growth factors, and functional fitness in older adult women with sarcopenia. Twenty-two older adult women aged over 65 with sarcopenia were randomly assigned to either resistance training (RT, n = 12) or non-exercise control group (CG, n = 10). The body weight-based and elastic band RT were performed three times a week, 60 min per session, for 16 weeks. Body composition and thigh muscle quality were estimated by dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT), respectively. The muscle growth factors, including growth differentiation factor-8 (GDF-8), growth differentiation factor-15 (GDF-15), activin A, and follistatin, were analyzed via blood samples. Statistical analyses were performed using repeated measures multivariate analysis of variance (MANOVA), analysis of variance (ANOVA), and effect size (i.e., cohen’s d, partial eta square), and the significance level was set at 0.05. The RT group improved their functional fitness, grip strength, gait speed, and isometric muscle strength (p < 0.01, d > 0.99; large), while these variables did not change in the CG. An increase in intramuscular fat was only observed in the CG (p < 0.01, 1.06; large). Muscle growth factors such as follistatin were significantly increased in the RT (p < 0.05, 0.81; large), but other variables did not change following resistance training. Sixteen weeks of resistance training improved functional fitness and prevented age-related increases in intramuscular fat in the thigh area. However, there were only some changes in muscle growth factors, such as follistatin, suggesting that the effectiveness of resistance training on muscle growth factors is limited. Body weight-based and elastic band resistance training is an alternative training method for sarcopenia to minimize the age-related adverse effects on muscle function and quality.
Efficacy Beliefs, Empowering Leadership, and Project Success in Public Research Centers: An Italian–Polish Study
Authors: Capaldo Guido , Capone Vincenza , Babiak Jolanta , Bajcar Beata , Kuchta Dorota
Published: June 2021

In the world of university research, although the figure of project manager is not formally foreseen, the principal researcher (PR) is, at many times, the last responsible the project results, schedule, and cost. The study aimed to investigate, in the light of the literature and through a cross-cultural study conducted in Italy and Poland, the relationship between soft skills (empowering leadership style, self-efficacy beliefs, and collective efficacy) of the principal researcher (PR) and the perceived success of research projects and satisfaction with the project, taking into account cross-cultural differences. A total of 67 PRs of complex projects in public universities (28 in Italy and 39 in Poland) participated in the study, completing a self-report questionnaire. Data were analyzed using descriptive and correlational analyses. The results showed a significantly higher mean value for team management self-efficacy in a Polish sample and a higher satisfaction with projects in Italian sample. All the soft skills included in the study were related to project success and satisfaction with the project. The results could be used to identify possible ways of intervention to establish a more mature project culture in public research organizations.
Are Cryptocurrencies a Backstop for the Stock Market in a COVID-19-Led Financial Crisis? Evidence from the NARDL Approach
Authors: Jeribi Ahmed , Jena Sangram Keshari , Lahiani Amine
Published: June 2021

The study investigates the safe haven properties and sustainability of the top five cryptocurrencies (Bitcoin, Ethereum, Dash, Monero, and Ripple) and gold for BRICS stock markets during the COVID-19 crisis period from 31 January 2020 to 17 September 2020 in comparison to the precrisis period from 1 January 2016 to 30 January 2020, in a nonlinear and asymmetric framework using Nonlinear Autoregressive Distributed Lag (NARDL) methodology. Our results show that the relationship dynamics of stock market and cryptocurrency returns both in the short and long run are changing during the COVID-19 crisis period, which justifies our study using the nonlinear and asymmetric model. As far as a sustainable safe haven is concerned, Dash and Ripple are found to be a safe haven for all the five markets before the pandemic. However, all five cryptocurrencies are found to be a safe haven for three emerging markets, such as Brazil, China, and Russia, during the financial crisis. In a comparative framework, gold is found to be a suitable safe haven only for Brazil and Russia. The results have implications for index fund managers of BRICS markets to include Dash and Ripple in their portfolio as safe haven assets to protect its value during a stock market crisis.
Exploring Allometric Scaling Relations between Fractal Dimensions of Metro Networks and Economic, Environmental and Social Indicators: A Case Study of 26 Cities in China
Authors: Lan Tian , Peng Qian , Wang Haoyu , Gong Xinyu , Li Jing , Shi Zhicheng
Published: June 2021

Allometric scaling originates in biology, where it refers to scaling relations between the size of a body part and the size of the whole body when an organism grows. In cities, various allometric relations have also been discovered, such as those between the complexity of traffic networks and urban quantities. Metro networks are typical traffic networks in cities. However, whether allometric relations with metro networks exist is still uncertain. In this study, “fractal dimension” was employed as the complexity measure of metro networks, and potential allometric relations between fractal dimensions and urban indicators in 26 main cities in China were explored. It was found that fractal dimensions of metro networks had positive allometric relations with gross domestic product (GDP), population, particulate matter with a diameter less than 2.5 microns (PM2.5), the road congestion index and the average price of second-hand housing (with Spearman’s R of 0.789, 0.806, 0.273, 0.625 and 0.335, respectively) but inverse allometric relations with sulfur dioxide (SO2) and residential satisfaction (with Spearman’s R of −0.270 and −0.419, respectively). Such discoveries imply that allometric relations do exist with metro networks, which is helpful in deepening our understanding of how metro systems interact with urban quantities in the self-organized evolution of cities.
Regulation of ADAM10 by the TspanC8 Family of Tetraspanins and Their Therapeutic Potential
Authors: Harrison Neale , Koo Chek Ziu , Tomlinson Michael G.
Published: June 2021

The ubiquitously expressed transmembrane protein a disintegrin and metalloproteinase 10 (ADAM10) functions as a “molecular scissor”, by cleaving the extracellular regions from its membrane protein substrates in a process termed ectodomain shedding. ADAM10 is known to have over 100 substrates including Notch, amyloid precursor protein, cadherins, and growth factors, and is important in health and implicated in diseases such as cancer and Alzheimer’s. The tetraspanins are a superfamily of membrane proteins that interact with specific partner proteins to regulate their intracellular trafficking, lateral mobility, and clustering at the cell surface. We and others have shown that ADAM10 interacts with a subgroup of six tetraspanins, termed the TspanC8 subgroup, which are closely related by protein sequence and comprise Tspan5, Tspan10, Tspan14, Tspan15, Tspan17, and Tspan33. Recent evidence suggests that different TspanC8/ADAM10 complexes have distinct substrates and that ADAM10 should not be regarded as a single scissor, but as six different TspanC8/ADAM10 scissor complexes. This review discusses the published evidence for this “six scissor” hypothesis and the therapeutic potential this offers.
Influence of the Anthocyanin and Cofactor Structure on the Formation Efficiency of Naturally Derived Pyranoanthocyanins
Authors: Miyagusuku-Cruzado Gonzalo , Voss Danielle M. , Giusti M. Monica
Published: June 2021

Pyranoanthocyanins are anthocyanin-derived pigments with higher stability to pH and storage. However, their slow formation and scarcity in nature hinder their industrial application. Pyranoanthocyanin formation can be accelerated by selecting anthocyanin substitutions, cofactor concentrations, and temperature. Limited information is available on the impacts of the chemical structure of the cofactor and anthocyanin; therefore, we evaluated their impacts on pyranoanthocyanin formation efficiency under conditions reported as favorable for the reaction. Different cofactors were evaluated including pyruvic acid, acetone, and hydroxycinnamic acids (p-coumaric, caffeic, ferulic, and sinapic acid) by incubating them with anthocyanins in a molar ratio of 1:30 (anthocyanin:cofactor), pH 3.1, and 45 °C. The impact of the anthocyanin aglycone was evaluated by incubating delphinidin, cyanidin, petunidin, or malvidin derivatives with the most efficient cofactor (caffeic acid) under identical conditions. Pigments were identified using UHPLC-PDA and tandem mass spectrometry, and pyranoanthocyanin formation was monitored for up to 72 h. Pyranoanthocyanin yields were the highest with caffeic acid (~17% at 72 h, p < 0.05). When comparing anthocyanins, malvidin-3-O-glycosides yielded twice as many pyranoanthocyanins after 24 h (~20%, p < 0.01) as cyanidin-3-O-glycosides. Petunidin- and delphinidin-3-O-glycosides yielded <2% pyranoanthocyanins. This study demonstrated the importance of anthocyanin and cofactor selection in pyranoanthocyanin production.
Neurological Immunotoxicity from Cancer Treatment
Authors: Wesley Sarah F. , Haggiagi Aya , Thakur Kiran T. , De Jager Philip L.
Published: June 2021

The emergence of immune-based treatments for cancer has led to a growing field dedicated to understanding and managing iatrogenic immunotoxicities that arise from these agents. Immune-related adverse events (irAEs) can develop as isolated events or as toxicities affecting multiple body systems. In particular, this review details the neurological irAEs from immune checkpoint inhibitors (ICI) and chimeric antigen receptor (CAR) T cell immunotherapies. The recognition and treatment of neurological irAEs has variable success, depending on the severity and nature of the neurological involvement. Understanding the involved mechanisms, predicting those at higher risk for irAEs, and establishing safety parameters for resuming cancer immunotherapies after irAEs are all important fields of ongoing research.
Methotrexate Neurotoxicity Is Related to Epigenetic Modification of the Myelination Process
Authors: Chen Yu-Chieh , Sheen Jiunn-Ming , Wang Su-Chen , Hsu Mei-Hsin , Hsiao Chih-Cheng , Chang Kow-Aung , Huang Li-Tung
Published: June 2021

With the improvement of the survival rate of acute lymphoblastic leukemia (ALL) in children, some children ALL survivors reveal inferior intellectual and cognition outcome. Methotrexate (MTX), while serving as an essential component in ALL treatment, has been reported to be related to various neurologic sequelae. Using combined intrathecal (IT) and intraperitoneal (IP) MTX model, we had demonstrated impaired spatial memory function in developing rats, which can be rescued by melatonin treatment. To elucidate the impact of MTX treatment on the epigenetic modifications of the myelination process, we examined the change of neurotrophin and myelination-related transcriptomes in the present study and found combined IT and IP MTX treatment resulted in altered epigenetic modification on the myelination process, mainly in the hippocampus. Further, melatonin can restore the MTX effect through alterations of the epigenetic pathways.
Genome-Wide SNP Markers for Genotypic and Phenotypic Differentiation of Melon (Cucumis melo L.) Varieties Using Genotyping-by-Sequencing
Authors: Hyun Do Yoon , Sebastin Raveendar , Lee Gi-An , Lee Kyung Jun , Kim Seong-Hoon , Yoo Eunae , Lee Sookyeong , Kang Man-Jung , Lee Seung Bum , Jang Ik , Ro Na-Young , Cho Gyu-Taek
Published: June 2021

Melon (Cucumis melo L.) is an economically important horticultural crop with abundant morphological and genetic variability. Complex genetic variations exist even among melon varieties and remain unclear to date. Therefore, unraveling the genetic variability among the three different melon varieties, muskmelon (C. melo subsp. melo), makuwa (C. melo L. var. makuwa), and cantaloupes (C. melo subsp. melo var. cantalupensis), could provide a basis for evolutionary research. In this study, we attempted a systematic approach with genotyping-by-sequencing (GBS)-derived single nucleotide polymorphisms (SNPs) to reveal the genetic structure and diversity, haplotype differences, and marker-based varieties differentiation. A total of 6406 GBS-derived SNPs were selected for the diversity analysis, in which the muskmelon varieties showed higher heterozygote SNPs. Linkage disequilibrium (LD) decay varied significantly among the three melon varieties, in which more rapid LD decay was observed in muskmelon (r2 = 0.25) varieties. The Bayesian phylogenetic tree provided the intraspecific relationships among the three melon varieties that formed, as expected, individual clusters exhibiting the greatest genetic distance based on the posterior probability. The haplotype analysis also supported the phylogeny result by generating three major networks for 48 haplotypes. Further investigation for varieties discrimination allowed us to detect a total of 52 SNP markers that discriminated muskmelon from makuwa varieties, of which two SNPs were converted into cleaved amplified polymorphic sequence markers for practical use. In addition to these markers, the genome-wide association study identified two SNPs located in the genes on chromosome 6, which were significantly associated with the phenotypic traits of melon seed. This study demonstrated that a systematic approach using GBS-derived SNPs could serve to efficiently classify and manage the melon varieties in the genebank.
Usher Syndrome: Genetics of a Human Ciliopathy
Authors: Fuster-García Carla , García-Bohórquez Belén , Rodríguez-Muñoz Ana , Aller Elena , Jaijo Teresa , Millán José M. , García-García Gema
Published: June 2021

Usher syndrome (USH) is an autosomal recessive syndromic ciliopathy characterized by sensorineural hearing loss, retinitis pigmentosa and, sometimes, vestibular dysfunction. There are three clinical types depending on the severity and age of onset of the symptoms; in addition, ten genes are reported to be causative of USH, and six more related to the disease. These genes encode proteins of a diverse nature, which interact and form a dynamic protein network called the “Usher interactome”. In the organ of Corti, the USH proteins are essential for the correct development and maintenance of the structure and cohesion of the stereocilia. In the retina, the USH protein network is principally located in the periciliary region of the photoreceptors, and plays an important role in the maintenance of the periciliary structure and the trafficking of molecules between the inner and the outer segments of photoreceptors. Even though some genes are clearly involved in the syndrome, others are controversial. Moreover, expression of some USH genes has been detected in other tissues, which could explain their involvement in additional mild comorbidities. In this paper, we review the genetics of Usher syndrome and the spectrum of mutations in USH genes. The aim is to identify possible mutation associations with the disease and provide an updated genotype–phenotype correlation.
Probiotics, Prebiotics and Epithelial Tight Junctions: A Promising Approach to Modulate Intestinal Barrier Function
Authors: Rose Elizabeth C. , Odle Jack , Blikslager Anthony T. , Ziegler Amanda L.
Published: June 2021

Disruptions in the intestinal epithelial barrier can result in devastating consequences and a multitude of disease syndromes, particularly among preterm neonates. The association between barrier dysfunction and intestinal dysbiosis suggests that the intestinal barrier function is interactive with specific gut commensals and pathogenic microbes. In vitro and in vivo studies demonstrate that probiotic supplementation promotes significant upregulation and relocalization of interepithelial tight junction proteins, which form the microscopic scaffolds of the intestinal barrier. Probiotics facilitate some of these effects through the ligand-mediated stimulation of several toll-like receptors that are expressed by the intestinal epithelium. In particular, bacterial-mediated stimulation of toll-like receptor-2 modulates the expression and localization of specific protein constituents of intestinal tight junctions. Given that ingested prebiotics are robust modulators of the intestinal microbiota, prebiotic supplementation has been similarly investigated as a potential, indirect mechanism of barrier preservation. Emerging evidence suggests that prebiotics may additionally exert a direct effect on intestinal barrier function through mechanisms independent of the gut microbiota. In this review, we summarize current views on the effects of pro- and prebiotics on the intestinal epithelial barrier as well as on non-epithelial cell barrier constituents, such as the enteric glial cell network. Through continued investigation of these bioactive compounds, we can maximize their therapeutic potential for preventing and treating gastrointestinal diseases associated with impaired intestinal barrier function and dysbiosis.
Can Developments in Tissue Optical Clearing Aid Super-Resolution Microscopy Imaging?
Authors: Matryba Paweł , Łukasiewicz Kacper , Pawłowska Monika , Tomczuk Jacek , Gołąb Jakub
Published: June 2021

The rapid development of super-resolution microscopy (SRM) techniques opens new avenues to examine cell and tissue details at a nanometer scale. Due to compatibility with specific labelling approaches, in vivo imaging and the relative ease of sample preparation, SRM appears to be a valuable alternative to laborious electron microscopy techniques. SRM, however, is not free from drawbacks, with the rapid quenching of the fluorescence signal, sensitivity to spherical aberrations and light scattering that typically limits imaging depth up to few micrometers being the most pronounced ones. Recently presented and robustly optimized sets of tissue optical clearing (TOC) techniques turn biological specimens transparent, which greatly increases the tissue thickness that is available for imaging without loss of resolution. Hence, SRM and TOC are naturally synergistic techniques, and a proper combination of these might promptly reveal the three-dimensional structure of entire organs with nanometer resolution. As such, an effort to introduce large-scale volumetric SRM has already started; in this review, we discuss TOC approaches that might be favorable during the preparation of SRM samples. Thus, special emphasis is put on TOC methods that enhance the preservation of fluorescence intensity, offer the homogenous distribution of molecular probes, and vastly decrease spherical aberrations. Finally, we review examples of studies in which both SRM and TOC were successfully applied to study biological systems.