bluuebunny/crossref_metadata_2025 huggingface dataset:
A Two-Moment Inequality with Applications to Rényi Entropy and Mutual Information
Authors: Reeves Galen
Published: November 2020

This paper explores some applications of a two-moment inequality for the integral of the rth power of a function, where 0<r<1. The first contribution is an upper bound on the Rényi entropy of a random vector in terms of the two different moments. When one of the moments is the zeroth moment, these bounds recover previous results based on maximum entropy distributions under a single moment constraint. More generally, evaluation of the bound with two carefully chosen nonzero moments can lead to significant improvements with a modest increase in complexity. The second contribution is a method for upper bounding mutual information in terms of certain integrals with respect to the variance of the conditional density. The bounds have a number of useful properties arising from the connection with variance decompositions.
Gallager Exponent Analysis of Coherent MIMO FSO Systems over Gamma-Gamma Turbulence Channels
Authors: Miao Maoke , Li Xiaofeng
Published: November 2020

This paper studies the Gallager’s exponent for coherent multiple-input multiple-output (MIMO) free space optical (FSO) communication systems over gamma–gamma turbulence channels. We assume that the perfect channel state information (CSI) is known at the receiver, while the transmitter has no CSI and equal power is allocated to all of the transmit apertures. Through the use of Hadamard inequality, the upper bound of the random coding exponent, the ergodic capacity and the expurgated exponent are derived over gamma–gamma fading channels. In the high signal-to-noise ratio (SNR) regime, simpler closed-form upper bound expressions are presented to obtain further insights into the effects of the system parameters. In particular, we found that the effects of small and large-scale fading are decoupled for the ergodic capacity upper bound in the high SNR regime. Finally, a detailed analysis of Gallager’s exponents for space-time block code (STBC) MIMO systems is discussed. Monte Carlo simulation results are provided to verify the tightness of the proposed bounds.
Remote Management Architecture of UAV Fleets for Maintenance, Surveillance, and Security Tasks in Solar Power Plants
Authors: Bemposta Rosende Sergio , Sánchez-Soriano Javier , Gómez Muñoz Carlos Quiterio , Fernández Andrés Javier
Published: November 2020

This article presents a remote management architecture of an unmanned aerial vehicles (UAVs) fleet to aid in the management of solar power plants and object tracking. The proposed system is a competitive advantage for sola r energy production plants, due to the reduction in costs for maintenance, surveillance, and security tasks, especially in large solar farms. This new approach consists of creating a hardware and software architecture that allows for performing different tasks automatically, as well as remotely using fleets of UAVs. The entire system, composed of the aircraft, the servers, communication networks, and the processing center, as well as the interfaces for accessing the services via the web, has been designed for this specific purpose. Image processing and automated remote control of the UAV allow generating autonomous missions for the inspection of defects in solar panels, saving costs compared to traditional manual inspection. Another application of this architecture related to security is the detection and tracking of pedestrians and vehicles, both for road safety and for surveillance and security issues of solar plants. The novelty of this system with respect to current systems is summarized in that all the software and hardware elements that allow the inspection of solar panels, surveillance, and people counting, as well as traffic management tasks, have been defined and detailed. The modular system presented allows the exchange of different specific vision modules for each task to be carried out. Finally, unlike other systems, calibrated fixed cameras are used in addition to the cameras embedded in the drones of the fleet, which complement the system with vision algorithms based on deep learning for identification, surveillance, and inspection.
An Improved Inverse-Time Over-Current Protection Method for a Microgrid with Optimized Acceleration and Coordination
Authors: Ji Liang , Cao Zhe , Hong Qiteng , Chang Xiao , Fu Yang , Shi Jiabing , Mi Yang , Li Zhenkun
Published: November 2020

This paper presents an improved inverse-time over-current protection method based on the compound fault acceleration factor and the beetle antennae search (BAS) optimization method for a microgrid. The proposed method can not only significantly increase the operation speed of the inverse-time over-current protection but also improve the protection coordination by considering the possible influential factors in terms of microgrid operation modes, distributed generation (DG) integration status, fault types, and positions, which are marked as the most challenging problems for over-current protection of a microgrid. In this paper, a new Time Dial Setting (TDS) of inverse-time protection is developed by applying a compound fault acceleration factor, which can notably accelerate the speed of protection by using low-voltage and short-circuit impedance during the fault. In order to improve the protection coordination, the BAS algorithm is then used to optimize the protection parameters of the pick-up current, TDS, and the inverse time curve shape coefficient. Finally, case studies and various evaluations based on DIgSILENT/Power Factory are carried out to illustrate the effectiveness of the proposed method.
Cation-Exchange Capacity Distribution within Hydrothermal Systems and Its Relation to the Alteration Mineralogy and Electrical Resistivity
Authors: Weisenberger Tobias Björn , Ingimarsson Heimir , Hersir Gylfi Páll , Flóvenz Ólafur G.
Published: November 2020

Cation-exchange capacity (CEC) measurements are widely used to quantify the smectite content in altered rocks. Within this study, we measure the CEC of drill cuttings in four wells from three different high-temperature geothermal areas in Iceland. The CEC measurements in all four wells show similar depth/temperature related pattern, and when comparing the CEC with electrical resistivity logs, we could show that the low resistivity zone coincides with CEC values >5 meq/100 g. The measurements show, in general, an exponential decrease of the CEC with increasing depth. At the facies boundary between the mixed-layer clay and epidote-chlorite zone, the CEC reaches a steady state at about 5 meq/100 g and below that it only decreases slightly within a linear trend with increasing depth. The facies boundary overlaps with the transition where the electrical resistivity logs show an increase in resistivity. It is shown that the measured CEC can be related to the clay mineral alteration within the geothermal system and the CEC reflects the smectite component within the interstratified chlorite/smectite minerals for similar alteration degree. Furthermore, CEC was measured in seven core samples from different alteration zones that had previously been studied in detail with respect to petrophysical and conductivity properties. The results show a clear correlation between CEC and the iso-electrical point, which describes the value of the pore fluid conductivity where transition from surface conductivity to pore fluid conductivity occurs. The presented study shows that the CEC within hydrothermal altered basaltic systems mimics the expandable clay mineral alteration zones and coincides with electrical logs. The presented method can, therefore, be an easy tool to quantify alteration facies within geothermal exploration and drilling projects.
Experimental Analysis and CFD Modeling for Conventional Basin-Type Solar Still
Authors: S. El-Sebaey Mahmoud , Ellman Asko , Hegazy Ahmed , Ghonim Tarek
Published: November 2020

With the rising population, environmental pollution, and social development, potable water is reducing and being contaminated day by day continually. Thus, several researchers have focused their studies on seas and oceans in order to get potable fresh water by desalination of their saltwater. Solar still of basin type is one of the available technologies to purify water because of free solar energy. The computational fluid dynamic CFD model of the solar still can significantly improve means for optimization of the solar still structure because it reduces the need for conducting large amount of experiments. Therefore, the main purpose of this study is presenting a multi-phase, three-dimensional CFD model, which predicts the performance of the solar still without using any experimental measurements, depending on the CFD solar radiation model. Simulated results are compared with experimental values of water and glass cover temperatures and yield of fresh water in climate conditions of Sheben El-Kom, Egypt (latitude 30.5° N and longitude 31.01° E). The simulation results were found to be in acceptable agreement with the experimental measured data. The results indicated that the daily simulated and experimental accumulated productivities of the single-slope solar still were found to be 1.982 and 1.785 L/m2 at a water depth of 2 cm. In addition, the simulated and experimental daily efficiency were around 16.79% and 15.5%, respectively, for the tested water depth.
CO2 Foam and CO2 Polymer Enhanced Foam for Heavy Oil Recovery and CO2 Storage
Authors: Telmadarreie Ali , Trivedi Japan J
Published: November 2020

Enhanced oil recovery (EOR) from heavy oil reservoirs is challenging. High oil viscosity, high mobility ratio, inadequate sweep, and reservoir heterogeneity adds more challenges and severe difficulties during any EOR method. Foam injection showed potential as an EOR method for challenging and heterogeneous reservoirs containing light oil. However, the foams and especially polymer enhanced foams (PEF) for heavy oil recovery have been less studied. This study aims to evaluate the performance of CO2 foam and CO2 PEF for heavy oil recovery and CO2 storage by analyzing flow through porous media pressure profile, oil recovery, and CO2 gas production. Foam bulk stability tests showed higher stability of PEF compared to that of surfactant-based foam both in the absence and presence of heavy crude oil. The addition of polymer to surfactant-based foam significantly improved its dynamic stability during foam flow experiments. CO2 PEF propagated faster with higher apparent viscosity and resulted in more oil recovery compared to that of CO2 foam injection. The visual observation of glass column demonstrated stable frontal displacement and higher sweep efficiency of PEF compared to that of conventional foam. In the fractured rock sample, additional heavy oil recovery was obtained by liquid diversion into the matrix area rather than gas diversion. Aside from oil production, the higher stability of PEF resulted in more gas storage compared to conventional foam. This study shows that CO2 PEF could significantly improve heavy oil recovery and CO2 storage.
Environmental Issues and Neurological Manifestations Associated with COVID-19 Pandemic: New Aspects of the Disease?
Authors: Bellocchio Luigi , Bordea Ioana Roxana , Ballini Andrea , Lorusso Felice , Hazballa Denisa , Isacco Ciro Gargiulo , Malcangi Giuseppina , Inchingolo Alessio Danilo , Dipalma Gianna , Inchingolo Francesco , Piscitelli Prisco , Logroscino Giancarlo , Miani Alessandro
Published: November 2020

Coronavirus (SARS-CoV-2) emerged in China in December 2019 and rapidly caused a global health pandemic. Current evidence seems to suggest a possible link with ecosystem disequilibrium and even air pollution. The primary manifestations affect respiratory and circulatory systems, but neurological features are also being reported through case reports and case series. We summarize neurological symptoms and complications associated with COVID-19. We have searched for original articles published in PubMed/Medline, PubMed Central and Google Scholar using the following keywords: “COVID-19”, “Coronavirus”, “pandemic”, “SARS-COV-2”, “neurology”, “neurological”, “complications” and “manifestations”. We found around 1000 publications addressing the issue of neurological conditions associated with COVID-19 infection. Amongst those, headache and dizziness are the most common reported symptoms followed by encephalopathy and delirium, while the most frequent complications are cerebrovascular accidents, Guillain–Barré syndrome, acute transverse myelitis, and acute encephalitis. Specific symptoms affecting the peripheral nervous system such as hyposmia and dysgeusia are the most common manifestations recorded in the selected studies. Interestingly, it was noted that these kinds of neurological symptoms might precede the typical features, such as fever and cough, in COVID patients. Neurological symptoms and complications associated with COVID-19 should be considered as a part of the clinical features of this novel global pandemic.
Integration of Spatial Probability and Size in Slope-Unit-Based Landslide Susceptibility Assessment: A Case Study
Authors: Li Langping , Lan Hengxing
Published: November 2020

Landslide spatial probability and size are two essential components of landslide susceptibility. However, in existing slope-unit-based landslide susceptibility assessment methods, landslide size has not been explicitly considered. This paper developed a novel slope-unit based approach for landslide susceptibility assessment that explicitly incorporates landslide size. This novel approach integrates the predicted occurrence probability (spatial probability) of landslides and predicted size (area) of potential landslides for a slope-unit to obtain a landslide susceptibility value for that slope-unit. The results of a case study showed that, from a quantitative point of view, integrating spatial probability and size in slope-unit-based landslide susceptibility assessment can bring remarkable increases of AUC (Area under the ROC curve) values. For slope-unit-based scenarios using the logistic regression method and the neural network method, the average increase of AUC brought by incorporating landslide size is up to 0.0627 and 0.0606, respectively. Slope-unit-based landslide susceptibility models incorporating landslide size had utilized the spatial extent information of historical landslides, which was dropped in models not incorporating landslide size, and therefore can make potential improvements. Nevertheless, additional case studies are still needed to further evaluate the applicability of the proposed approach.
Cohort Profile: ZOE 2.0—A Community-Based Genetic Epidemiologic Study of Early Childhood Oral Health
Authors: Divaris Kimon , Slade Gary D. , Ferreira Zandona Andrea G. , Preisser John S. , Ginnis Jeannie , Simancas-Pallares Miguel A. , Agler Cary S. , Shrestha Poojan , Karhade Deepti S. , Ribeiro Apoena de Aguiar , Cho Hunyong , Gu Yu , Meyer Beau D. , Joshi Ashwini R. , Azcarate-Peril M. Andrea , Basta Patricia V. , Wu Di , North Kari E.
Published: November 2020

Early childhood caries (ECC) is an aggressive form of dental caries occurring in the first five years of life. Despite its prevalence and consequences, little progress has been made in its prevention and even less is known about individuals’ susceptibility or genomic risk factors. The genome-wide association study (GWAS) of ECC (“ZOE 2.0”) is a community-based, multi-ethnic, cross-sectional, genetic epidemiologic study seeking to address this knowledge gap. This paper describes the study’s design, the cohort’s demographic profile, data domains, and key oral health outcomes. Between 2016 and 2019, the study enrolled 8059 3–5-year-old children attending public preschools in North Carolina, United States. Participants resided in 86 of the state’s 100 counties and racial/ethnic minorities predominated—for example, 48% (n = 3872) were African American, 22% white, and 20% (n = 1611) were Hispanic/Latino. Seventy-nine percent (n = 6404) of participants underwent clinical dental examinations yielding ECC outcome measures—ECC (defined at the established caries lesion threshold) prevalence was 54% and the mean number of decayed, missing, filled surfaces due to caries was eight. Nearly all (98%) examined children provided sufficient DNA from saliva for genotyping. The cohort’s community-based nature and rich data offer excellent opportunities for addressing important clinical, epidemiologic, and biological questions in early childhood.
Roles of Physiological Responses and Anthropometric Factors on the Gravitational Force Tolerance for Occupational Hypergravity Exposure
Authors: Tu Min-Yu , Chu Hsin , Chen Hsin-Hui , Chiang Kwo-Tsao , Hu Je-Ming , Li Fang-Ling , Yang Chen-Shu , Cheng Chao-Chien , Lai Chung-Yu
Published: November 2020

Gravity in the head-to-toe direction, known as +Gz (G force), forces blood to pool in the lower body. Fighter pilots experience decreases in blood pressure when exposed to hypergravity in flight. Human centrifuge has been used to examine the G tolerance and anti-G straining maneuver (AGSM) techniques of military pilots. Some factors that may affect G tolerance have been reported but are still debated. The aim of this study was to investigate the physiological responses and anthropometric factors correlated with G tolerance. We retrospectively reviewed the training records of student pilots who underwent high G training. Variables were collected to examine their correlations with the outcome of 7.5G sustained for 15 s (7.5G profile). There were 873 trainees who underwent 7.5G profile training, 44 trainees (5.04%) could not sustain the test for 15 s. The group with a small heart rate (HR) increase (less than 10%) during the first 1–5 s of the 7.5G profile had a nearly ten-fold higher failing chance compared with the large HR increase group (adjusted odds ratio: 9.91; 95% confidence interval: 4.11–23.88). The chances of failure were inversely related to the HR increase percentage (p for trend <0.001). Factors, including body mass index, relaxed and straining G tolerance, and AGSM, were found to be negatively correlated with the outcome.
Prevalence of and Factors Associated with Cardiometabolic Risks and Lung Function Impairment among Middle-Aged Women in Rural Taiwan
Authors: Lin Ming-Shyan , Yeh Mei-Hua , Chen Mei-Yen
Published: November 2020

Background: This study aims to explore the prevalence of and factors associated with cardiometabolic risks and lung function impairment among middle-aged women. Methods: A nurse-led community health development and cross-sectional study design was applied in Yunlin County, Taiwan. Lung function test was performed by a certified technician using a valid spirometer, during annual community health checkups conducted by a collaborating local hospital. Lung function impairment and cardiometabolic risks were measured and defined, based on the medical diagnosis and the national standard, by the hospital. Results: From a total of 439 middle-aged women, the prevalence of lung function impairment and metabolic syndrome were 26% and 47.2%, respectively. Many women adopted few health habits, e.g., only 30.5% engaged in regular exercise. A significant association between lung function impairment and four cardiometabolic risk factors (p < 0.05) was found. The multivariate logistic regression analysis showed that adopting few exercises (OR = 0.56, 95% CI 0.36–0.87) and lung function impairment (OR = 2.12, 95% CI 1.34–3.35) were independently associated with metabolic syndrome, after adjusting for confounding factors, such as age and education. Conclusions: The findings revealed that middle-aged women have a high prevalence of cardiometabolic risks and lung function impairment. Lung function impairment and physical inactivity were independently associated with an increased risk of having metabolic syndrome.
A Flexible Lockdown by Integrating Public Health and Economic Reactivation to Response the Crisis of COVID-19: Responses to Comments by Alvaro J Idrovo on “An Examination on the Transmission of COVID-19 and the Effect of Response Strategies: A Comparative Analysis”
Authors: Chen Yi-Tui , Yen Yung-Feng , Yu Shih-Heng , Chia-Yu Su Emily
Published: November 2020

We greatly appreciate Idrovo’s comments on our research and wish to specifically respond to his comments. Idrovo indicates that rapid increases in the number of confirmed cases in the past few weeks were observed in Latin America, where some countries had implemented stringent lockdowns for more than three months since the second half of March 2020. In his comments, Idrovo expresses his suspicion on the reality of lockdowns implemented in Latin America and worries about the negative impacts of lockdowns on economies. We thank the Editor for providing us with the opportunity to respond to Idrovo’s comments and explain parts of our study.
Special Weapons and Tactics Occupational-Specific Physical Assessments and Fitness Measures
Authors: Strader Jessica , Schram Ben , Irving Shane , Robinson Jeremy , Orr Robin
Published: November 2020

Specialist tactical response police are required to frequently perform physically demanding tasks at high-risk capability levels, emphasizing the need for optimal physical fitness in this population. The aim of this study was to investigate the relationships between select measures of physical fitness and performance on an occupational-specific physical assessment (OSPA). A retrospective analysis on 18 male specialist police candidates (age = 32.1 ± 5.04 yrs; height = 183.72 ± 5.79 cm; body mass = 89.44 ± 8.56 kg; body mass index (BMI) = 26.45 ± 1.58 kg/m2) was conducted. Data were comprised of anthropometric measures, assorted fitness measures and OSPA performance scores. A stepwise linear regression determined the influence of measured fitness parameters on OSPA performance. A regression featuring both the 1 RM military shoulder press and grip strength of the non-dominant hand was the most significant predictor of performance (adjusted r2 = 0.565, p = 0.001). A separate model, exclusively using the 1 RM military shoulder press additionally predicted OSPA performance (adjusted r2 = 0.240, p = 0.023). These results emphasize the importance of optimal upper-limb muscular strength and its impact on key occupational tasks in specialist police candidates.
Health Care Needs and Services for Elder and Disabled Population: Findings from a Barcelona Study
Authors: Rodriguez-Pereira Jessica , de Armas Jesica , Garbujo Lorenzo , Ramalhinho Helena
Published: November 2020

Health care is a pillar of modern society. This study focuses on the use of descriptive analytics to provide demographic and territorial insights that will be of strategic importance in planning subsequent projects meant to improve health care services. We especially focus on the assessment of the elder and disabled population health care needs in Barcelona, and evaluate to what extent the current health care infrastructure is successful in covering the demand of these fragile population segment. This work is developed around three main assessments in the municipality of Barcelona: the elder and disabled health care demand, the available health care services, and the relationship between demand and services, showing that territorial and demographic aspects are relevant in assessing the health needs of the population.
Transmission and Long-Term Colonization Patterns of Staphylococcus aureus in a Nursing Home
Authors: Kasela Martyna , Grzegorczyk Agnieszka , Korona-Głowniak Izabela , Ossowski Mateusz , Nowakowicz-Dębek Bożena , Malm Anna
Published: November 2020

Nursing homes might create an environment favorable for the transmission of Staphylococcus aureus because of the presence of hospitalized elderly, overcrowding and close contacts among people. We aimed at identifying risk factors for S. aureus colonization and determining the genetic relatedness of isolates demonstrating transmission among people. We investigated 736 swab samples from 92 residents and personnel for the presence of S. aureus. Swabs from anterior nares and throat were collected quarterly (2018) in a nursing home located in Poland. Genotyping was conducted using the multi-locus variable number of tandem repeats fingerprinting (MLVF) method. We observed high seasonal variation in the proportion of participants colonized with methicillin-resistant Staphylococcus aureus (MRSA) strains (0% to 13.5%). A multivariate analysis revealed that residents aged more than 85 years old are at risk for becoming intermittent S. aureus carriers (p = 0.013). The MLVF analysis revealed a high genetic diversity among methicillin-sensitive S. aureus (MSSA) strains and close genetic relatedness between MRSA strains. We proved the advanced aged were predisposed to intermittent S. aureus carriage. Genotyping revealed the transmission of S. aureus among the participants living in a closed environment. A high genetic relatedness among isolated MRSA suggests its clonal spread in the nursing home.
Sex Hormone-Binding Globulin (SHBG) as an Early Biomarker and Therapeutic Target in Polycystic Ovary Syndrome
Authors: Qu Xianqin , Donnelly Richard
Published: November 2020

Human sex hormone-binding globulin (SHBG) is a glycoprotein produced by the liver that binds sex steroids with high affinity and specificity. Clinical observations and reports in the literature have suggested a negative correlation between circulating SHBG levels and markers of non-alcoholic fatty liver disease (NAFLD) and insulin resistance. Decreased SHBG levels increase the bioavailability of androgens, which in turn leads to progression of ovarian pathology, anovulation and the phenotypic characteristics of polycystic ovarian syndrome (PCOS). This review will use a case report to illustrate the inter-relationships between SHBG, NAFLD and PCOS. In particular, we will review the evidence that low hepatic SHBG production may be a key step in the pathogenesis of PCOS. Furthermore, there is emerging evidence that serum SHBG levels may be useful as a diagnostic biomarker and therapeutic target for managing women with PCOS.
Analysis of Melanoma Secretome for Factors That Directly Disrupt the Barrier Integrity of Brain Endothelial Cells
Authors: Anchan Akshata , Martin Olivia , Hucklesby James J. W. , Finlay Graeme , Johnson Rebecca H. , Robilliard Laverne D. , O’Carroll Simon J. , Angel Catherine E. , Graham E Scott
Published: November 2020

We have recently demonstrated that invasive melanoma cells are capable of disrupting the brain endothelial barrier integrity. This was shown using ECIS biosensor technology, which revealed rapid disruption via the paracellular junctions. In this paper, we demonstrate that melanoma cells secrete factors (e.g., cytokines) that weaken the endothelial barrier integrity. Through proteome profiling, we attempt to identify the barrier-disrupting cytokines. Melanoma conditioned media were collected from three New Zealand melanoma lines. ECIS technology was used to assess if the conditioned media disrupted the endothelial barrier independent of the melanoma cells. The melanoma cell secretome was assessed using cytometric bead array (CBA), Luminex immunoassay and multiplex Proteome Profilers, to detect the expression of secretory proteins, which may facilitate metastasis. Finally, ECIS technology was used to assess the direct effects of secreted proteins identified as candidates from the proteome screens. We show that melanoma-conditioned media significantly disrupted the brain endothelial barrier, however, to a much lesser extent than the cells from which they were collected. Cytokine and proteome profiling of the conditioned media showed evidence of high concentrations of approximately 15 secreted proteins (including osteopontin, IL-8, GDF-15, MIF and VEGF). These 15 secreted proteins were expressed variably across the melanoma lines. Surprisingly, the addition of these individually to the brain endothelial cells did not substantially affect the barrier integrity. ANGPTL-4 and TGFβ were also produced by the melanoma cells. Whilst TGFβ-1 had a pronounced effect on the barrier integrity, surprisingly ANGPTL-4 did not. However, its C-terminal fragment did and within a very similar period to the conditioned media, albeit not to the same extent. Herein we show that melanoma cells produce a wide-range of soluble factors at high concentrations, which most likely favour support or survival of the cancer cells. Most of these, except for TGFβ-1 and the C-terminal fragment of ANGPTL-4, did not have an impact on the integrity of the brain endothelial cells.
The Role of Scaffolds in Tendon Tissue Engineering
Authors: Vasiliadis Angelo V. , Katakalos Konstantinos
Published: November 2020

Tendons are unique forms of connective tissue aiming to transmit the mechanical force of muscle contraction to the bones. Tendon injury may be due to direct trauma or might be secondary to overuse injury and age-related degeneration, leading to inflammation, weakening and subsequent rupture. Current traditional treatment strategies focus on pain relief, reduction of the inflammation and functional restoration. Tendon repair surgery can be performed in people with tendon injuries to restore the tendon’s function, with re-rupture being the main potential complication. Novel therapeutic approaches that address the underlying pathology of the disease is warranted. Scaffolds represent a promising solution to the challenges associated with tendon tissue engineering. The ideal scaffold for tendon tissue engineering needs to exhibit physiologically relevant mechanical properties and to facilitate functional graft integration by promoting the regeneration of the native tissue.
Sustainable Entrepreneurship in the Transport and Retail Supply Chain Sector
Authors: Negrutiu Cristian , Vasiliu Cristinel , Enache Calcedonia
Published: November 2020

The present study investigated the factors that influence the feasibility and competitive advantage of a digital freight forwarder through a binary logistic regression model. The research is a concrete application of sustainable entrepreneurship in the transport and supply chain sector. The novelty of this topic presents a research gap that needs to be covered with dedicated studies. After the literature review and concept clarification, the article presents quantitative research involving an online questionnaire administered among a sample of transporters in Romania. Through analysis of the data collected from 405 respondents, it was found that the most important factors when selecting a digital freight forwarder are the existence of both sales and dispatch departments. Furthermore, apart from greening the industry, a digital freight forwarder has several other advantages for all stakeholders and society. The study concludes that the concept has the potential to disrupt the entire industry through a unique combination of efficiency, transparency, and sustainability.
Synthesis and Application of N-methylphthalimidylazo Disperse Dyes to Cellulose Diacetate for High Wash Fastness
Authors: Yoon Sanghyun , Kim Hyunjung , Lee Eunkyo , Oh Nahyun , Kim Sangcheon , Hong Kyung Hwa , Koh Joonseok
Published: November 2020

Cellulose diacetate fibers were prepared from cellulosic biomass with high α-cellulose contents such as purified cotton linters and wood pulps. Cellulose diacetate fibers are sensitive to alkaline solution, which causes hydrolysis of the acetate ester to hydroxyl groups, especially at high temperatures. Thus, the low alkali-resistance of cellulose acetate fibers makes it difficult to achieve high wash fastness by restricting the application of intense after-treatment, such as reduction clearing. A series of N-methylphthalimide-based high-washable azo disperse dyes were synthesized and their dyeing and fastness properties on cellulose diacetate fabrics were investigated. From the overall results obtained in this study, N-methylphthalimidylazo disperse dyes are expected to be a desirable alternative to high value-added dyes that can be used for high color fastness dyeing of cellulose diacetate with a minimal discharge of wastewater during washing process.
Piezoelectric Particulate Composite for Energy Harvesting from Mechanical Vibration
Authors: Grzybek Dariusz , Kata Dariusz , Sikora Wojciech , Sapiński Bogdan , Micek Piotr , Pamuła Hanna , Huebner Jan , Rutkowski Paweł
Published: November 2020

Energy harvesting from mechanical vibration of buildings is usually realized by the use of devices, in which the main element is a prismatic beam with a rectangular cross-section. The beam has been the subject of scientific research; it is usually constructed with a carrying substrate that does not have piezoelectric characteristics and from piezoelectric material. In contrast, this investigation sought to create a beam structure with a piezoelectric composite only. The entire beam structure was made of a prototype piezoelectric particulate composite. Based on courses of voltage obtained in laboratory experiments and known geometry of the specimens, a series of finite element method (FEM) simulations was performed, aiming to estimate the piezoelectric coefficient d31 value at which the mentioned voltage could be achieved. In each specimen, sedimentation caused the formation of two distinct layers: top and bottom. The experiments revealed that the presented prototype piezoelectric particulate composite converts mechanical stress to electric energy in bending mode, which is used in energy harvesting from mechanical vibration. It is self-supporting and thus a carrying substrate is not required in the harvester structure.
Effect of Laser Remelting on Cladding Layer of Inconel 718 Superalloy Formed by Laser Metal Deposition
Authors: Xin Bo , Ren Jiangyu , Wang Xiaoqi , Zhu Lida , Gong Yadong
Published: November 2020

The brittle phase (Laves) of Inconel 718 parts formed by laser metal deposition (LMD) represents a bottleneck of the engineering applications. In order to investigate effectiveness of laser remelting (LR) technology on suppressing the formation of Laves phase, different laser scanning speeds of the LR process were adopted to build and remelt the single-pass cladding layers. The evolution of phase composition, microstructural morphology, and hardness of the LMD and LMD + LR specimens were analyzed. The experimental results show that different laser scanning speeds can obviously change the microstructural evolutions, Laves phase, and hardness. A low laser scanning speed (360 mm/min) made columnar dendrite uninterruptedly grow from the bottom to the top of the cladding layer. A high laser scanning speed (1320 mm/min) has a significant effect on refining Laves phase and reducing Nb segregation. When the laser scanning speed of LR process is equal to that of LMD, the cladding layers can be completely remelted and the content of Laves phase of the LMD + LR layer is 22.4% lower than that of the LMD layer. As the laser scanning speed increases from 360 to 1320 mm/min, the mean primary dendrite arm spacing (PDAS) values of the remelting area decrease from 6.35 to 3.28 μm gradually. In addition, the low content of Laves phase and porosity contribute to the growth of average hardness. However, the laser scanning speed has a little effect on the average hardness and the maximum average hardness difference of the LMD and LMD + LR layers is only 12.4 HV.
Mean-Variance Portfolio Selection with Tracking Error Penalization
Authors: Lefebvre William , Loeper Grégoire , Pham Huyên
Published: November 2020

This paper studies a variation of the continuous-time mean-variance portfolio selection where a tracking-error penalization is added to the mean-variance criterion. The tracking error term penalizes the distance between the allocation controls and a reference portfolio with same wealth and fixed weights. Such consideration is motivated as follows: (i) On the one hand, it is a way to robustify the mean-variance allocation in the case of misspecified parameters, by “fitting" it to a reference portfolio that can be agnostic to market parameters; (ii) On the other hand, it is a procedure to track a benchmark and improve the Sharpe ratio of the resulting portfolio by considering a mean-variance criterion in the objective function. This problem is formulated as a McKean–Vlasov control problem. We provide explicit solutions for the optimal portfolio strategy and asymptotic expansions of the portfolio strategy and efficient frontier for small values of the tracking error parameter. Finally, we compare the Sharpe ratios obtained by the standard mean-variance allocation and the penalized one for four different reference portfolios: equal-weights, minimum-variance, equal risk contributions and shrinking portfolio. This comparison is done on a simulated misspecified model, and on a backtest performed with historical data. Our results show that in most cases, the penalized portfolio outperforms in terms of Sharpe ratio both the standard mean-variance and the reference portfolio.
Cure Models with Exponentiated Weibull Exponential Distribution for the Analysis of Melanoma Patients
Authors: Omer Mohamed Elamin Abdallah Mohamed Elamin , Bakar Mohd Rizam Abu , Adam Mohd Bakri , Mustafa Mohd Shafie
Published: November 2020

In the survival data analysis, commonly, it is presumed that all study subjects will eventually have the event of concern. Nonetheless, it tends to be unequivocally expected that a fraction of these subjects will never expose to the event of interest. The cure rate models are usually used to model this type of data. In this paper, we introduced a maximum likelihood estimates analysis for the four-parameter exponentiated Weibull exponential (EWE) distribution in the existence of cured subjects, censored observations, and predictors. Aiming to include the fraction of unsusceptible (cured) individuals in the analysis, a mixture cure model, and two non-mixture cure models—bounded cumulative hazard model, and geometric non-mixture model with EWE distribution—are proposed. The mixture cure model provides a better fit to real data from a Melanoma clinical trial compared to the other two non-mixture cure models.
Controls on Associations of Clay Minerals in Phanerozoic Evaporite Formations: An Overview
Authors: Yaremchuk Yaroslava , Hryniv Sofiya , Peryt Tadeusz , Vovnyuk Serhiy , Meng Fanwei
Published: November 2020

Information on the associations of clay minerals in Upper Proterozoic and Phanerozoic marine evaporite formations suggests that cyclic changes in the (SO4-rich and Ca-rich) chemical type of seawater during the Phanerozoic could affect the composition of associations of authigenic clay minerals in marine evaporite deposits. The vast majority of evaporite clay minerals are authigenic. The most common are illite, chlorite, smectite and disordered mixed-layer illite-smectite and chlorite-smectite; all the clay minerals are included regardless of their quantity. Corrensite, sepiolite, palygorskite and talc are very unevenly distributed in the Phanerozoic. Other clay minerals (perhaps with the exception of kaolinite) are very rare. Evaporites precipitated during periods of SO4-rich seawater type are characterized by both a greater number and a greater variety of clay minerals—smectite and mixed-layer minerals, as well as Mg-corrensite, palygorskite, sepiolite, and talc, are more common in associations. The composition of clay mineral association in marine evaporites clearly depends on the chemical type of seawater and upon the brine concentration in the evaporite basin. Along with increasing salinity, aggradational transformations of clay minerals lead to the ordering of their structure and, ideally, to a decrease in the number of minerals. In fact, evaporite deposits of higher stages of brine concentration often still contain unstable clay minerals. This is due to the intense simultaneous volcanic activity that brought a significant amount of pyroclastic material into the evaporite basin; intermediate products of its transformation (in the form of swelling minerals) often remained in the deposits of the potassium salt precipitation stage.
Secondary Metabolites and Their Bioactivities Produced by Paecilomyces
Authors: Dai Ze-Bao , Wang Xin , Li Guo-Hong
Published: November 2020

Paecilomyces, a common saprobic filamentous fungus, not only plays an important role in biological control, but also has applications in medicine, food, and environmental protection. In this paper, 223 secondary metabolites and their bioactivities from 13 known species and various unidentified strains of Paecilomyces are reviewed. Their structures can be described as polyketide, terpenoid, peptide, alkaloid, quinone, pyrone, sterol, and fatty acid. They have been demonstrated varying biological activities, including antimicrobial, antitumor, insecticidal, antiplasmodial, antimalarial, nematicidal, herbicidal, and enzyme-inhibiting. This review provides a comprehensive overview of secondary metabolites and their biological activities from strains of Paecilomyces.
PLGA Membranes Functionalized with Gelatin through Biomimetic Mussel-Inspired Strategy
Authors: Carmagnola Irene , Chiono Valeria , Ruocco Gerardina , Scalzone Annachiara , Gentile Piergiorgio , Taddei Paola , Ciardelli Gianluca
Published: November 2020

Electrospun membranes have been widely used as scaffolds for soft tissue engineering due to their extracellular matrix-like structure. A mussel-inspired coating approach based on 3,4-dihydroxy-DL-phenylalanine (DOPA) polymerization was proposed to graft gelatin (G) onto poly(lactic-co-glycolic) acid (PLGA) electrospun membranes. PolyDOPA coating allowed grafting of gelatin to PLGA fibers without affecting their bulk characteristics, such as molecular weight and thermal properties. PLGA electrospun membranes were dipped in a DOPA solution (2 mg/mL, Tris/HCl 10 mM, pH 8.5) for 7 h and then incubated in G solution (2 mg/mL, Tris/HCl 10 mM, pH 8.5) for 16 h. PLGA fibers had an average diameter of 1.37 ± 0.23 µm. Quartz crystal microbalance with dissipation technique (QCM-D) analysis was performed to monitor DOPA polymerization over time: after 7 h the amount of deposited polyDOPA was 71 ng/cm2. After polyDOPA surface functionalization, which was, also revealed by Raman spectroscopy, PLGA membranes maintained their fibrous morphology, however the fiber size and junction number increased. Successful functionalization with G was demonstrated by FTIR-ATR spectra, which showed the presence of G adsorption bands at 1653 cm−1 (Amide I) and 1544 cm−1 (Amide II) after G grafting, and by the Kaiser Test, which revealed a higher amount of amino groups for G functionalized membranes. Finally, the biocompatibility of the developed substrates and their ability to induce cell growth was assessed using Neonatal Normal Human Dermal Fibroblasts.
Ultra-Flexible Organic Photovoltaics with Nanograting Patterns Based on CYTOP/Ag Nanowires Substrate
Authors: Heo Soo Won
Published: November 2020

In this study, we developed a method for fabricating ultrathin polymer substrates that can be used in ultra-flexible organic photovoltaics (OPVs) via a non-vacuum process using cyclic transparent optical polymer. In addition, a Ag nanowire network layer was used as a transparent electrode in a solution process. All processes were conducted on large area via spin coating. The power conversion efficiency (PCE) of the ultra-flexible OPV improved by 6.4% compared to the PCE of the ITO/Glass-based OPV. In addition, the PCE of the OPV increased to 10.12% after introducing nanostructures in the ZnO and photoactive layers. We performed 1000 cycles of compression/relaxation tests to evaluate the mechanical properties of the ultra-flexible OPV, after which, the PCE remained at 67% of the initial value. Therefore, the developed OPV system is suitable as a power source for portable devices.
Nuts and Non-Alcoholic Fatty Liver Disease: Are Nuts Safe for Patients with Fatty Liver Disease?
Authors: Plaz Torres Maria Corina , Bodini Giorgia , Furnari Manuele , Marabotto Elisa , Zentilin Patrizia , Giannini Edoardo G.
Published: November 2020

Diet and lifestyle interventions are the recommended treatment for patients with non-alcoholic fatty liver disease (NAFLD), with the aim of achieving a 7–10% weight loss. Several dietary patterns have been suggested for this purpose, however, to date, the best one is represented by the Mediterranean diet (MD) as it is rich in macro- and micro- nutrients known for their effectiveness in health-promotion and cardio-vascular disease prevention. Moreover, MD is characterized by the inclusion of nuts. These foods have shown potential benefits in health-promotion as they are rich in fibers, which have lipid-lowering effects, rich in mono- and poly-unsaturated fatty acids, which help reduce insulin-resistance and serum cholesterol, and contain anti-oxidants which reduce oxidative stress and inflammation. Additionally, nuts are associated with a better control, or reduction, of Body Mass Index (BMI). All these effects are useful targets to achieve in NAFLD, so that nuts have been proposed as a suitable dietary treatment supplement for weight and metabolic control in these patients. In recent years, health authorities raised an alert on nuts consumption as these may be at high risk of aflatoxin (AF) contamination, for which controls and legislations are different among countries. AF is a well-known cancerogenic agent and a recognized risk factor for hepatocellular carcinoma. Patients with NAFLD have an overall, inherent sevenfold increased risk of developing hepatocellular carcinoma as compared with the general population. In this context, one could argue that recommending the inclusion of nuts in the diet of NAFLD patients has to be balanced with the risk of potential chronic exposure to AF, and every effort should be pursued to assure the safety of these nutrients. In this review, we aim to summarize the benefits of nuts consumption, the evidence for AF contamination of nuts and the consequent potential risks in patients with NAFLD.
Nutrition Can Help DNA Repair in the Case of Aging
Authors: Kaźmierczak-Barańska Julia , Boguszewska Karolina , Karwowski Boleslaw T.
Published: November 2020

Micronutrients such as vitamins and trace elements are crucial for maintaining the health of all organisms. Micronutrients are involved in every cellular/biochemical process. They play roles in proper heart and brain functioning, influence immunological responses, and antioxidant defense systems. Therefore, prolonged deficiency in one or more micronutrients leads to cardiovascular or neurodegenerative disorders. Keeping micronutrients at adequate levels is especially important for seniors. They are prone to deficiencies due to age-associated functional decline and often to a diet poor in nutrients. Moreover, lack of micronutrients has an indirect impact on the genome. Their low levels reduce the activity of antioxidant enzymes, and therefore inhibit the efficiency of defense against free radicals which can lead to the formation of DNA lesions. The more DNA damage in the genetic material, the faster aging at the cellular level and a higher risk of pathological processes (e.g., carcinogenesis). Supplementation of crucial antioxidative micronutrients such as selenium, zinc, vitamin C, and vitamin E seems to have the potential to positively influence the condition of an aging organism, including minimizing inflammation, enhancing antioxidative defense, and limiting the formation of DNA lesions. In consequence, it may lead to lowering the risk and incidence of age-related diseases such as cardiovascular diseases, neurodegenerative diseases, and malnutrition. In this article, we attempt to present the synergistic action of selected antioxidant micronutrients (vitamin C, vitamin E, selenium, and zinc) for inhibiting oxidative stress and DNA damage, which may impede the process of healthy aging.