bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of a Faraday Cup Collimator for Electric Propulsion Device Beam Study: Case of a Hall Thruster
Authors: Valentin Hugonnaud , Stéphane Mazouffre
Published: March 2021

A Faraday cup (FC) is an instrument dedicated to current measurement in beams, jets and plasmas. It consists of a set of polarized electrodes mounted in such a way plasma sheath effect can be neglected, yielding accurate and reliable results. A FC is composed of three main parts, namely a collector or cup, which collects the current, a collimator, which defines the collection area and can contribute to limit electrons from entering the cup and a housing which protects the instrument from perturbation caused by the surrounding medium. In this paper, we provide experimental results of the effect of the collimator upon the measured ion current within the beam of a low-power Hall thruster. Different collimator materials, aperture diameters and polarization voltages are studied to determine the optimum design. Minimum dimension as well as appropriate materials are given as a conclusion in the case of low-power Hall thruster beam investigation.
Patterns of Extreme Precipitation and Characteristics of Related Systems in the Northern Xinjiang Region
Authors: Xu Rui , Ming Jie
Published: March 2021

Based on 40 years of daily precipitation, 272 extreme precipitation days in the Northern Xinjiang region are defined. Using the daily precipitation data on these days, four precipitation spatial patterns were obtained through principal component analysis. Then, daily-averaged reanalysis data were used to analyze the variations of synoptic systems on extreme precipitation days and the two days before and after. The rainfall centers shifted with the influential systems at 500 hPa. Water vapor of the western Tianshan type (Type WT) and the north of Northern Xinjiang type (Type NN) comes from the west, while vapor of the Central Tianshan type (Type CT) mainly comes from the east. In the east of Northern Xinjiang type (Type EN), water vapor converges from both sides. The centers of the upper-level jets are located west of 80° E in Type WT and CT. However, they are to the east of 80° E in the other types. This article summarizes the variations of the systems at 500 hPa, the South Asia High, the westerly jet, and the water vapor transport between the surface and 500 hPa in four types of patterns, and builds the conceptual model for each type. The models built can be applied to the heavy rainfall forecast of Northern Xinjiang.
Documented and Simulated Warm Extremes during the Last 600 Years over Monsoonal China
Authors: Zhou Shangrong , Tao Le , Su Yun , Sui Yue , Zhang Zhongshi
Published: March 2021

In this study, we present an analysis of warm extremes over monsoonal China (21–45° N, 106–124° E) during the last 600 years based on Chinese historical documents and simulations from the Paleoclimate Modelling Intercomparison Project Phase 3 (PMIP3) and the Coupled Model Intercomparison Project Phase 5 (CMIP5). The Chinese historical documents indicate that extreme warm records become more frequent after ~1650 CE in North China and ~1850 CE in the Yangtze River Valley. Our analyses of two threshold extreme temperature indices also illustrate that warm extremes have become more frequent since the 17th century in North China and the mid-19th century in Yangtze River Valley in good agreement with the changes in warm extremes revealed in the historical documents. This agreement suggests potential mechanisms behind the shift of periods, which should be further investigated in the future.
The Graph of Our Mind
Authors: Szalkai Balázs , Varga Bálint , Grolmusz Vince
Published: March 2021

Graph theory in the last two decades penetrated sociology, molecular biology, genetics, chemistry, computer engineering, and numerous other fields of science. One of the more recent areas of its applications is the study of the connections of the human brain. By the development of diffusion magnetic resonance imaging (diffusion MRI), it is possible today to map the connections between the 1–1.5 cm2 regions of the gray matter of the human brain. These connections can be viewed as a graph. We have computed 1015-vertex graphs with thousands of edges for hundreds of human brains from one of the highest quality data sources: the Human Connectome Project. Here we analyze the male and female braingraphs graph-theoretically and show statistically significant differences in numerous parameters between the sexes: the female braingraphs are better expanders, have more edges, larger bipartition widths, and larger vertex cover than the braingraphs of the male subjects. These parameters are closely related to the quality measures of highly parallel computer interconnection networks: the better expanding property, the large bipartition width, and the large vertex cover characterize high-quality interconnection networks. We apply the data of 426 subjects and demonstrate the statistically significant (corrected) differences in 116 graph parameters between the sexes.
Rat Locomotion Detection Based on Brain Functional Directed Connectivity from Implanted Electroencephalography Signals
Authors: Li Bo , Zhang Minjian , Liu Yafei , Hu Dingyin , Zhao Juan , Tang Rongyu , Lang Yiran , He Jiping
Published: March 2021

Previous findings have suggested that the cortex involved in walking control in freely locomotion rats. Moreover, the spectral characteristics of cortical activity showed significant differences in different walking conditions. However, whether brain connectivity presents a significant difference during rats walking under different behavior conditions has yet to be verified. Similarly, whether brain connectivity can be used in locomotion detection remains unknown. To address those concerns, we recorded locomotion and implanted electroencephalography signals in freely moving rats performing two kinds of task conditions (upslope and downslope walking). The Granger causality method was used to determine brain functional directed connectivity in rats during these processes. Machine learning algorithms were then used to categorize the two walking states, based on functional directed connectivity. We found significant differences in brain functional directed connectivity varied between upslope and downslope walking. Moreover, locomotion detection based on brain connectivity achieved the highest accuracy (91.45%), sensitivity (90.93%), specificity (91.3%), and F1-score (91.43%). Specifically, the classification results indicated that connectivity features in the high gamma band contained the most discriminative information with respect to locomotion detection in rats, with the support vector machine classifier exhibiting the most efficient performance. Our study not only suggests that brain functional directed connectivity in rats showed significant differences in various behavioral contexts but also proposed a method for classifying the locomotion states of rat walking, based on brain functional directed connectivity. These findings elucidate the characteristics of neural information interaction between various cortical areas in freely walking rats.
Effect of Prism Adaptation Therapy on the Activities of Daily Living and Awareness for Spatial Neglect: A Secondary Analysis of the Randomized, Controlled Trial
Authors: Mizuno Katsuhiro , Tsujimoto Kengo , Tsuji Tetsuya
Published: March 2021

Background: Rehabilitation for unilateral spatial neglect (USN) using prism adaptation (PA) is one of the most widely used methods, and the effectiveness of PA is well-evidenced. Although the effect of PA generalized various neglect symptoms, the effectiveness for some aspects of neglect is not fully proven. The Catherine Bergego Scale (CBS) was developed to identify problems with the activities of daily living (ADL) caused by USN. The CBS is composed of 10 observation assessments and a self-assessment questionnaire. To assess the self-awareness of USN, the anosognosia score is calculated as the difference between the observational scores and the self-assessment scores. To investigate how PA affects ADL and self-awareness in subacute USN patients during rehabilitation, we analyzed each item of the CBS and self-awareness from a randomized, controlled trial (RCT) that we previously conducted (Mizuno et al., 2011). Methods: A double-masked randomized, controlled trial was conducted to evaluate the effects of a 2-week PA therapy on USN in 8 hospitals in Japan. We compared each item of the CBS, anosognosia score, and absolute value of the anosognosia score between the prism group and the control group. Results: Two of ten items (gaze orientation and exploration of personal belongings) were significantly improved in the prism group compared with those in the control group. The absolute value of the anosognosia score was significantly improved by PA. Conclusions: Improvement of oculomotor exploration by PA may generalize the behavioral level in a daily living environment. This study suggested that PA could accelerate the self-awareness of neglect during subacute rehabilitation.
Differential Susceptibility to the Impact of the COVID-19 Pandemic on Working Memory, Empathy, and Perceived Stress: The Role of Cortisol and Resilience
Authors: Baliyan Shishir , Cimadevilla José , de Vidania Silvia , Pulopulos Matías , Sandi Carmen , Venero César
Published: March 2021

There are important individual differences in adaptation and reactivity to stressful challenges. Being subjected to strict social confinement is a distressful psychological experience leading to reduced emotional well-being, but it is not known how it can affect the cognitive and empathic tendencies of different individuals. Cortisol, a key glucocorticoid in humans, is a strong modulator of brain function, behavior, and cognition, and the diurnal cortisol rhythm has been postulated to interact with environmental stressors to predict stress adaptation. The present study investigates in 45 young adults (21.09 years old, SD = 6.42) whether pre-pandemic diurnal cortisol indices, overall diurnal cortisol secretion (AUCg) and cortisol awakening response (CAR) can predict individuals’ differential susceptibility to the impact of strict social confinement during the Coronavirus Disease 2019 (COVID-19) pandemic on working memory, empathy, and perceived stress. We observed that, following long-term home confinement, there was an increase in subjects’ perceived stress and cognitive empathy scores, as well as an improvement in visuospatial working memory. Moreover, during confinement, resilient coping moderated the relationship between perceived stress scores and pre-pandemic AUCg and CAR. In addition, in mediation models, we observed a direct effect of AUCg and an indirect effect of both CAR and AUCg, on change in perceived self-efficacy. These effects were parallelly mediated by the increase in working memory span and cognitive empathy. In summary, our findings reveal the role of the diurnal pattern of cortisol in predicting the emotional impact of the COVID-19 pandemic, highlighting a potential biomarker for the identification of at-risk groups following public health crises.
Cultural Intelligence of Expatriate Health Workers in an Inuit Context: An Exploration of Managerial Competency Profiles
Authors: Morin Geneviève , Talbot David
Published: March 2021

Developing cultural diversity skills is a major ethical challenge for organizations operating within marginalized communities. This study defines cultural intelligence profiles us a two-step approach. In the first step, managers (n = 31) are invited to complete a Cultural Intelligence Quotient Assessment Test to identify and describe different managerial profiles. In the second step, semi-structured interviews are conducted (n = 17) to better understand the characteristics of the managerial profiles developed in phase one. The findings indicate that there are three typical managerial profiles: (1) The opportunist, (2) the modern missionary, and (3) the seasoned sage. These managerial profiles highlight the emerging dynamics of the cultural intelligence model and provide a better understanding of the career trajectories of managers in the healthcare sector. The results also have important managerial implications, particularly concerning strategies for training managers working with marginalized populations.
Impact of Nitrogen, Boron and Phosphorus Impurities on the Electronic Structure of Diamond Probed by X-ray Spectroscopies
Authors: Choudhury Sneha , Golnak Ronny , Schulz Christian , Lieutenant Klaus , Tranchant Nicolas , Arnault Jean-Charles , Pinault-Thaury Marie-Amandine , Jomard François , Knittel Peter , Petit Tristan
Published: March 2021

Doping diamond with boron, nitrogen or phosphorus enables a fine tuning of its electronic properties, which is particularly relevant for applications involving electron emission. However, the chemical nature of the doping sites and its correlation with electron emission properties remain to be clarified. In this work, we applied soft X-ray spectroscopy techniques to probe occupied and unoccupied electronic states in undoped, boron-, phosphorus- and nitrogen-containing single crystal diamonds. X-ray absorption, X-ray emission and X-ray photoemission spectroscopies, performed at the carbon K-edge, provide a full picture of new electronic states created by impurities in diamond. The different probing depths of fluorescence- and electron-based detection techniques enable a comparison between surface and bulk contributions.
Stimuli-Responsive Hydrogels for Cancer Treatment: The Role of pH, Light, Ionic Strength and Magnetic Field
Authors: Andrade Fernanda , Roca-Melendres Maria Mercé , Durán-Lara Esteban F. , Rafael Diana , Schwartz Simó
Published: March 2021

Cancer remains as the second leading cause of death, worldwide. Despite the enormous important advances observed in the last decades, advanced stages of the disease remain incurable. The severe side effects associated to systemic high doses of chemotherapy and the development of drug resistance impairs a safe and efficiency anticancer therapy. Therefore, new formulations are continuously under research and development to improve anticancer drugs therapeutic index through localized delivery at tumor sites. Among a wide range of possibilities, hydrogels have recently gained special attention due to their potential to allow in situ sustained and controlled anticancer drug release. In particular, stimuli-responsive hydrogels which are able to change their physical state from liquid to gel accordingly to external factors such as temperature, pH, light, ionic strength, and magnetic field, among others. Some of these formulations presented promising results for the localized control and treatment of cancer. The present work aims to discuss the main properties and application of stimuli-responsive hydrogels in cancer treatment and summarize the most important advances observed in the last decades focusing on the use of pH-, light-, ionic strength-, and magnetic-responsive hydrogels.
The Role of microRNAs in the Cisplatin- and Radio-Resistance of Cervical Cancer
Authors: Masadah Rina , Rauf Syahrul , Pratama Muhammad Yogi , Tiribelli Claudio , Pascut Devis
Published: March 2021

Cervical cancer is the fourth leading cause of cancer-related death among women worldwide. The chemotherapeutical agent cisplatin, a small platinum-based compound, is considered as the standard therapy for locally advanced cervical cancer or recurrent cancers, sometimes in combination with radiotherapy or other drugs. However, drug resistance and radio-resistance phenomena could reduce the life expectancy of cervical cancer patients. Resistance mechanisms are complex and often involve multiple cellular pathways in which microRNAs (miRNAs) play a fundamental role. miRNAs are a class of endogenous non-coding small RNAs responsible for post-transcriptional gene regulation. Convincing evidence demonstrates that several deregulated miRNAs are important regulators in the onset of drug and radioresistance in cervical cancer, thus underlying their potential applications in a clinical setting. In this review, we summarized the mechanisms by which miRNAs affect both cisplatin and radioresistance in cervical cancer. We also described the regulatory loops between miRNAs and lncRNAs promoting drug resistance. Besides, we reported evidence for the role of miRNAs in sensitizing cancer cells to cisplatin-based chemotherapy, and provided some suggestions for the development of new combined therapies for cervical cancer.
Radiobiological Studies of Microvascular Damage through In Vitro Models: A Methodological Perspective
Authors: Possenti Luca , Mecchi Laura , Rossoni Andrea , Sangalli Veronica , Bersini Simone , Cicchetti Alessandro , Costantino Maria Laura , Candrian Christian , Arrigoni Chiara , Rancati Tiziana , Moretti Matteo
Published: March 2021

Ionizing radiation (IR) is used in radiotherapy as a treatment to destroy cancer. Such treatment also affects other tissues, resulting in the so-called normal tissue complications. Endothelial cells (ECs) composing the microvasculature have essential roles in the microenvironment’s homeostasis (ME). Thus, detrimental effects induced by irradiation on ECs can influence both the tumor and healthy tissue. In-vitro models can be advantageous to study these phenomena. In this systematic review, we analyzed in-vitro models of ECs subjected to IR. We highlighted the critical issues involved in the production, irradiation, and analysis of such radiobiological in-vitro models to study microvascular endothelial cells damage. For each step, we analyzed common methodologies and critical points required to obtain a reliable model. We identified the generation of a 3D environment for model production and the inclusion of heterogeneous cell populations for a reliable ME recapitulation. Additionally, we highlighted how essential information on the irradiation scheme, crucial to correlate better observed in vitro effects to the clinical scenario, are often neglected in the analyzed studies, limiting the translation of achieved results.
Growth Arrest-Specific Gene 6 Administration Ameliorates Sepsis-Induced Organ Damage in Mice and Reduces ROS Formation In Vitro
Authors: Salmi Livia , Gavelli Francesco , Patrucco Filippo , Bellan Mattia , Sainaghi Pier Paolo , Avanzi Gian Carlo , Castello Luigi Mario
Published: March 2021

Sepsis is a widespread life-threatening disease, with a high mortality rate due to inflammation-induced multiorgan failure (MOF). Thus, new effective modulators of the immune response are urgently needed to ameliorate the outcome of septic patients. As growth arrest-specific gene 6 (Gas6)/Tyro3, Axl, MerTK (TAM) receptors signaling has shown immunomodulatory activity in sepsis, here we sought to determine whether Gas6 protein injection could mitigate MOF in a cecal slurry mouse model of sepsis. Mice, divided into different groups according to treatment—i.e., placebo (B), ampicillin (BA), Gas6 alone (BG), and ampicillin plus Gas6 (BAG)—were assessed for vitality, histopathology and cytokine expression profile as well as inducible nitric oxide synthase (iNOS), ALT and LDH levels. BAG-treated mice displayed milder kidney and lung damage and reduced levels of cytokine expression and iNOS in the lungs compared to BA-treated mice. Notably, BAG-treated mice showed lower LDH levels compared to controls. Lastly, BAG-treated cells of dendritic, endothelial or monocytic origin displayed reduced ROS formation and increased cell viability, with a marked upregulation of mitochondrial activity. Altogether, our findings indicate that combined treatment with Gas6 and antibiotics ameliorates sepsis-induced organ damage and reduces systemic LDH levels in mice, suggesting that Gas6 intravenous injection may be a viable therapeutic option in sepsis.
Direct Conversion of Human Fibroblasts into Adipocytes Using a Novel Small Molecular Compound: Implications for Regenerative Therapy for Adipose Tissue Defects
Authors: Sowa Yoshihiro , Kishida Tsunao , Louis Fiona , Sawai Seiji , Seki Makoto , Numajiri Toshiaki , Takahashi Kenji , Mazda Osam
Published: March 2021

There is a need in plastic surgery to prepare autologous adipocytes that can be transplanted in patients to reconstruct soft tissue defects caused by tumor resection, including breast cancer, and by trauma and other diseases. Direct conversion of somatic cells into adipocytes may allow sufficient functional adipocytes to be obtained for use in regeneration therapy. Chemical libraries of 10,800 molecules were screened for the ability to induce lipid accumulation in human dermal fibroblasts (HDFs) in culture. Chemical compound-mediated directly converted adipocytes (CCCAs) were characterized by lipid staining, immunostaining, and qRT-PCR, and were also tested for adipokine secretion and glucose uptake. CCCAs were also implanted into mice to examine their distribution in vivo. STK287794 was identified as a small molecule that induced the accumulation of lipid droplets in HDFs. CCCAs expressed adipocyte-related genes, secreted adiponectin and leptin, and abundantly incorporated glucose. After implantation in mice, CCCAs resided in granulation tissue and remained adipose-like. HDFs were successfully converted into adipocytes by adding a single chemical compound, STK287794. C/EBPα and PPARγ were upregulated in STK287794-treated cells, which strongly suggests involvement of these adipocyte-related transcription factors in the chemical direct conversion. Our method may be useful for the preparation of autogenous adipocytes for transplantation therapy for soft tissue defects and fat tissue atrophy.
Sociodemographic and Pre-Linguistic Factors in Early Vocabulary Acquisition
Authors: Serrat-Sellabona Elisabet , Aguilar-Mediavilla Eva , Sanz-Torrent Mònica , Andreu Llorenç , Amadó Anna , Serra Miquel
Published: March 2021

Here, we studied the beginnings of language development, jointly assessing two groups of precursors, sociodemographic and pre-linguistic, that have previously been studied separately. Thus, the general objective of this study was to explore which factors best explained the acquisition of initial expressive vocabulary. The sample consisted of 504 participants from Catalan-speaking homes with ages ranging between 10 and 18 months. The data were obtained through the MacArthur–Bates Communicative Development Inventories (MCB-CDIs). Vocabulary development shows a lexical spurt at 17 months. Regression analyses show that pre-linguistic factors have more explanatory power of than sociodemographic ones. Within the sociodemographic variables, age, birth order and birth weight explain part of the vocabulary variance. With respect to pre-linguistic variables, imitation, late gestures and phrase comprehension are predictors of the initial vocabulary acquisition. Specifically, imitation and late gestures were the pre-linguistic behaviours that made it possible to distinguish between children with higher and lower levels of vocabulary. We discussed these findings in relation to their relevance for language acquisition and for the early assessment of linguistic competence.
Impact of Different Types of Nosocomial Infection on the Neurodevelopmental Outcome of Very Low Birth Weight Infants
Authors: Pichler Karin , Giordano Vito , Tropf Gereon , Fuiko Renate , Berger Angelika , Rittenschober-Boehm Judith
Published: March 2021

Nosocomial infections (NIs) are important conditions associated with mortality and morbidity in very low birth weight infants (VLBWIs). The aim of this study was to investigate the impact of NIs and the different subtypes on neurodevelopmental outcomes in a cohort of VLBWIs. VLBWIs born with a gestational age between 23 0/7 and 31 6/7 weeks in a level III neonatal center were enrolled. Neonatal morbidities as well as the neurodevelopmental outcome at 2 years of corrected age were analyzed. Six-hundred infants completed the study successfully. Of these, 38% experienced an NI episode. NIs were associated with an increased risk of neonatal complications, such as brain injury, bronchopulmonary dysplasia (BPD) and death, and were a significant risk factor for adverse motor development at 2 years of corrected age in our cohort of VLBWIs. The negative impact of NIs on neurodevelopmental outcomes was particularly associated with necrotizing enterocolitis (NEC), suspected NIs and Gram-positive NIs. This study demonstrated that NIs are a significant risk factor for both morbidity and mortality as well as adverse neurodevelopmental outcomes in VLBWIs.
Low-Cost Nanostructured Coating of Anodic Aluminium Oxide Synthesized in Sulphuric Acid as Electrolyte
Authors: Bruera Florencia A. , Kramer Gustavo R. , Vera María L. , Ares Alicia E.
Published: March 2021

The anodic oxidation of aluminium is an electrochemical technique that allows obtaining nanostructures with easily adjustable morphology depending on the synthesis variables, for its application in medicine, engineering, biotechnology, electronics, etc. In this work, low-cost aluminium oxide nanostructured films were synthesized and morphologically characterized using two anodization steps in sulphuric acid, varying the concentration and temperature of the electrolyte and anodization voltage. The order of the porous matrix, pore diameter, interpore distance, pore density, thickness, and porosity were measured and statistically analyzed. The results showed that under the proposed conditions it is possible to synthesize low-cost nanoporous aluminium oxide films, with a short-range ordering, being the best ordering conditions 10 °C and 0.3 M sulphuric acid at 20 V and 5 °C and 2 M sulphuric acid at 15 V. Furthermore, it was determined that the pore diameter and the interpore distance vary proportionally with the voltage, that the pore density decreases with the voltage and increases with the concentration of the electrolyte, and that the thickness of the oxide film increases with electrolyte concentration, temperature, and anodization voltage.
Nanocomposite Inks Based on Nickel–Silver Core–Shell and Silver Nanoparticles for Fabrication Conductive Coatings at Low-Temperature Sintering
Authors: Pajor-Świerzy Anna , Szendera Franciszek , Pawłowski Radosław , Szczepanowicz Krzysztof
Published: March 2021

Nanocomposite inks composed of nickel–silver core–shell and silver nanoparticles (NPs) can combine the advantages of lower cost, high conductivity, and low-temperature sintering processes, which have attracted much attention in the development of materials for printed flexible electronics. In this context, in the present paper, we report the process of preparation of nanocomposite ink containing nickel–silver core–shell nanoparticles, as the main filler, and silver nanoparticles, as doping material, and their application for the fabrication of conductive coatings. It was found that the addition of a low concentration of Ag NPs to ink formulation based mainly on low-cost Ni-Ag NPs improves the conductive properties of coatings fabricated by ink deposition on a glass substrate. Two types of prepared nanocomposite ink coatings showed promising properties for future application: (1) doped with 0.5% of Ag NPs sintered at 200 °C as low cost for larger industrial application and, (2) containing 1% of Ag NPs sintered at 150 °C for the fabrication of conductive printed patterns on flexible substrates. The conductivity of such nanocomposite films was similar, about of 6 × 106 S/m, which corresponds to 35% of that for a bulk nickel.
Traveling Wave Solutions of a Four Dimensional Reaction-Diffusion Model for Porcine Reproductive and Respiratory Syndrome with Time Dependent Infection Rate
Authors: Suksamran Jeerawan , Lenbury Yongwimon , Koonprasert Sanoe
Published: March 2021

Porcine reproductive and respiratory syndrome virus (PRRSV) causes reproductive failure in sows and respiratory disease in piglets and growing pigs. The disease rapidly spreads in swine populations, making it a serious problem causing great financial losses to the swine industry. However, past mathematical models used to describe the spread of the disease have not yielded sufficient understanding of its spatial transmission. This work has been designed to investigate a mathematical model for the spread of PRRSV considering both time and spatial dimensions as well as the observed decline in infectiousness as time progresses. Moreover, our model incorporates into the dynamics the assumption that some members of the infected population may recover from the disease and become immune. Analytical solutions are derived by using the modified extended hyperbolic tangent method with the introduction of traveling wave coordinate. We also carry out a stability and phase analysis in order to obtain a clearer understanding of how PRRSV spreads spatially through time.
Smart and Sustainable Hair Products Based on Chitin-Derived Compounds
Authors: Morganti Pierfrancesco , Morganti Gianluca , Coltelli Maria-Beatrice
Published: March 2021

According to previous research studies, consumers worldwide are searching for new natural-oriented hair products that are both skin and environmentally friendly. Worldwide waste and air pollution, with the consequent environmental disasters, represent the greatest risk to human health and economy, further increased by the COVID-19 pandemic. Among others, non-biodegradable molecules are present in hair products (fossil-based additives, surfactants, etc.) and macromolecules (plastics). Plastics waste is considered the most serious problem, representing a forecast amount of 460 million tons per year by 2030, 12% of which is reused or recycled. Most plastics consumed, therefore, go to landfills and incineration, also if their recycling is considered an important driver of industrial profitability. Thus, the use of biopolymers represents an interesting alternative to produce biodegradable goods and tissues. After an introduction to the worldwide waste problem and the hair structure, the present review proposes the possibility to make biodegradable tissues that, realized by chitin nanofibrils and nano-lignin as natural polymers, may be used to produce an innovative and smart cosmetic hairline. Chitin-derived compounds are considered interesting polymers to produce non-woven tissues able to repair the hair damages provoked by the aggressiveness of both the environment and some aggressive cosmetic treatments, such as setting, bleaching, permanent waving, and oxidative coloring. The possible activity, that positively charged polymers such as chitin could have, has been speculated, interfering with the constitution and organization of the hair fibrils’ structure, which is negatively charged. The possibility of selecting biopolymers for their packaging is also discussed. Moreover, the use of these biopolymers, obtained from forestry-agro-food waste, may be of help to safeguard the further consumption of natural raw materials, necessary for future generations, also maintaining the earth’s biodiversity.
Hair Shaft Examination: A Practical Tool to Diagnose Griscelli Syndrome
Authors: Montero-Vilchez Trinidad , Remon-Love Alexandra , Tercedor-Sánchez Jesús , Arias-Santiago Salvador
Published: March 2021

Griscelli syndrome (GS) is a rare disease that is characterized by silvery hair and fair skin. It is included in congenital grey hair syndromes, a rare group of autosomal recessive disorders characterized by silvery grey hair and severe multisystem disorders, such as immune system impairment, defects in immunological function, ocular and skeletal alterations, and nervous system defects. Herein, we report a rare case of GS type 1 and highlight the importance of a dermatological and hair examination to make an early diagnosis of these life-threatening diseases.
Divergent Importance of Chronobiological Considerations in High- and Low-dose Melatonin Therapies
Authors: Hardeland Rüdiger
Published: March 2021

Melatonin has been used preclinically and clinically for different purposes. Some applications are related to readjustment of circadian oscillators, others use doses that exceed the saturation of melatonin receptors MT1 and MT2 and are unsuitable for chronobiological purposes. Conditions are outlined for appropriately applying melatonin as a chronobiotic or for protective actions at elevated levels. Circadian readjustments require doses in the lower mg range, according to receptor affinities. However, this needs consideration of the phase response curve, which contains a silent zone, a delay part, a transition point and an advance part. Notably, the dim light melatonin onset (DLMO) is found in the silent zone. In this specific phase, melatonin can induce sleep onset, but does not shift the circadian master clock. Although sleep onset is also under circadian control, sleep and circadian susceptibility are dissociated at this point. Other limits of soporific effects concern dose, duration of action and poor individual responses. The use of high melatonin doses, up to several hundred mg, for purposes of antioxidative and anti-inflammatory protection, especially in sepsis and viral diseases, have to be seen in the context of melatonin’s tissue levels, its formation in mitochondria, and detoxification of free radicals.
Satisfaction-Based Energy Allocation with Energy Constraint Applying Cooperative Game Theory
Authors: Ortiz Samira , Ndoye Mandoye , Castro-Sitiriche Marcel
Published: March 2021

There has been an effort for a few decades to keep energy consumption at a minimum or at least within a low-level range. This effort is more meaningful and complex by including a customer’s satisfaction variable to ensure that customers can achieve the best quality of life that could be derived from how energy is used by different devices. We use the concept of Shapley Value from cooperative game theory to solve the multi-objective optimization problem (MOO) to responsibly fulfill user’s satisfaction by maximizing satisfaction while minimizing the power consumption, with energy constrains since highly limited resources scenarios are studied. The novel method uses the concept of a quantifiable user satisfaction, along the concepts of power satisfaction (PS) and energy satisfaction (ES). The model is being validated by representing a single house (with a small PV system) that is connected to the utility grid. The main objectives are to (i) present the innovative energy satisfaction model based on responsible wellbeing, (ii) demonstrate its implementation using a Shapley-value-based algorithm, and (iii) include the impact of a solar photovoltaic (PV) system in the energy satisfaction model. The proposed technique determines in which hours the energy should be allocated to maximize the ES for each scenario, and then it is compared to cases in which devices are usually operated. Through the proposed technique, the energy consumption was reduced 75% and the ES increased 40% under the energy constraints.
Forecasting Charging Demand of Electric Vehicles Using Time-Series Models
Authors: Kim Yunsun , Kim Sahm
Published: March 2021

This study compared the methods used to forecast increases in power consumption caused by the rising popularity of electric vehicles (EVs). An excellent model for each region was proposed using multiple scaled geographical datasets over two years. EV charging volumes are influenced by various factors, including the condition of a vehicle, the battery’s state-of-charge (SOC), and the distance to the destination. However, power suppliers cannot easily access this information due to privacy issues. Despite a lack of individual information, this study compared various modeling techniques, including trigonometric exponential smoothing state space (i.e., Trigonometric, Box–Cox, Auto-Regressive-Moving-Average (ARMA), Trend, and Seasonality (TBATS)), autoregressive integrated moving average (ARIMA), artificial neural networks (ANN), and long short-term memory (LSTM) modeling, based on past values and exogenous variables. The effect of exogenous variables was evaluated in macro- and micro-scale geographical areas, and the importance of historic data was verified. The basic statistics regarding the number of charging stations and the volume of charging in each region are expected to aid the formulation of a method that can be used by power suppliers.
Influence of Silica Nano-Additives on Performance and Emission Characteristics of Soybean Biodiesel Fuelled Diesel Engine
Authors: Gavhane R. S. , Kate A. M. , Soudagar Manzoore Elahi M. , Wakchaure V. D. , Balgude Sagar , Rizwanul Fattah I. M. , Nik-Ghazali Nik-Nazri , Fayaz H. , Khan T. M. Yunus , Mujtaba M. A. , Kumar Ravinder , Shahabuddin M.
Published: March 2021

The present study examines the effect of silicon dioxide (SiO2) nano-additives on the performance and emission characteristics of a diesel engine fuelled with soybean biodiesel. Soybean biofuel was prepared using the transesterification process. The morphology of nano-additives was studied using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). The Ultrasonication process was used for the homogeneous blending of nano-additives with biodiesel, while surfactant was used for the stabilisation of nano-additives. The physicochemical properties of pure and blended fuel samples were measured as per ASTM standards. The performance and emissions characteristics of different fuel samples were measured at different loading conditions. It was found that the brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) increased by 3.48–6.39% and 5.81–9.88%, respectively, with the addition of SiO2 nano-additives. The carbon monoxide (CO), hydrocarbon (HC) and smoke emissions for nano-additive added blends were decreased by 1.9–17.5%, 20.56–27.5% and 10.16–23.54% compared to SBME25 fuel blends.
Estimating Wind Farm Transformers Rating through Lifetime Characterization Based on Stochastic Modeling of Wind Power
Authors: Fantauzzi Maurizio , Lauria Davide , Mottola Fabio , Proto Daniela
Published: March 2021

This paper deals with the problem of the optimal rating of mineral-oil-immersed transformers in large wind farms. The optimal rating is derived based on the probabilistic analyses of wind power generation through the Ornstein–Uhlenbeck stochastic process and on thermal model of the transformer through the integration of stochastic differential equations. These analyses allow the stochastic characterization of lifetime reduction of the transformer and then its optimal rating through a simple closed form. The numerical application highlights the effectiveness and easy applicability of the proposed methodology. The proposed methodology allows deriving the rating of transformers which better fits the specific peculiarities of wind power generation. Compared to the conventional approaches, the proposed method can better adapt the transformer size to the intermittence and variability of the power generated by wind farms, thus overcoming the often-recognized reduced lifetime.
Pd Catalysts Supported on Bamboo-Like Nitrogen-Doped Carbon Nanotubes for Hydrogen Production
Authors: Suboch Arina N. , Podyacheva Olga Y.
Published: March 2021

Bamboo-like nitrogen-doped carbon nanotubes (N-CNTs) were used to synthesize supported palladium catalysts (0.2–2 wt.%) for hydrogen production via gas phase formic acid decomposition. The beneficial role of nitrogen centers of N-CNTs in the formation of active isolated palladium ions and dispersed palladium nanoparticles was demonstrated. It was shown that although the surface layers of N-CNTs are enriched with graphitic nitrogen, palladium first interacts with accessible pyridinic centers of N-CNTs to form stable isolated palladium ions. The activity of Pd/N-CNTs catalysts is determined by the ionic capacity of N-CNTs and dispersion of metallic nanoparticles stabilized on the nitrogen centers. The maximum activity was observed for the 0.2% Pd/N-CNTs catalyst consisting of isolated palladium ions. A ten-fold increase in the concentration of supported palladium increased the contribution of metallic nanoparticles with a mean size of 1.3 nm and decreased the reaction rate by only a factor of 1.4.
A Study of Developing a Prediction Equation of Electricity Energy Output via Photovoltaic Modules
Authors: Kim Minsu , Kim Hongmyeong , Jung Jae Hak
Published: March 2021

Various equations are being developed and applied to predict photovoltaic (PV) module generation. Currently, quite diverse methods for predicting module generation are available, with most equations showing accuracy with ≤5% error. However, the accuracy can be determined only when the module temperature and the value of irradiation that reaches the module surface are precisely known. The prediction accuracy of outdoor generation is actually extremely low, as the method for predicting outdoor module temperature has extremely low accuracy. The change in module temperature cannot be predicted accurately because of the real-time change of irradiation and air temperature outdoors. Calculations using conventional equations from other studies show a mean error of temperature difference of 4.23 °C. In this study, an equation was developed and verified that can predict the precise module temperature up to 1.64 °C, based on the experimental data obtained after installing an actual outdoor module.
Latent Heat Thermal Storage of Nano-Enhanced Phase Change Material Filled by Copper Foam with Linear Porosity Variation in Vertical Direction
Authors: Ghalambaz Mohammad , Shahabadi Mohammad , Mehryan S. A. M , Sheremet Mikhail , Younis Obai , Talebizadehsardari Pouyan , Yaici Wabiha
Published: March 2021

The melting flow and heat transfer of copper-oxide coconut oil in thermal energy storage filled with a nonlinear copper metal foam are addressed. The porosity of the copper foam changes linearly from bottom to top. The phase change material (PCM) is filled into the metal foam pores, which form a composite PCM. The natural convection effect is also taken into account. The effect of average porosity; porosity distribution; pore size density; the inclination angle of enclosure; and nanoparticles’ concentration on the isotherms, melting maps, and the melting rate are investigated. The results show that the average porosity is the most important parameter on the melting behavior. The variation in porosity from 0.825 to 0.9 changes the melting time by about 116%. The natural convection flows are weak in the metal foam, and hence, the impact of each of the other parameters on the melting time is insignificant (less than 5%).
Simulation Studies of Control Systems for Doubly Fed Induction Generator Supplied by the Current Source Converter
Authors: Kroplewski Paweł , Morawiec Marcin , Jąderko Andrzej , Odeh Charles
Published: March 2021

The control system for a Doubly Fed Induction Generator (DFIG) supplied by a grid-connected Current Source Converter (CSC) is presented in this paper. Nonlinear transformation of DFIG model to the multi-scalar form is proposed. The nonlinear control strategy of active and reactive power of DFIG is realized by feedback linearization. In the proposed control scheme, the DFIG model and CSI parameters are included. Two Proportional-Integral (PI) controllers are dedicated for the control of the respective active and reactive powers. The control variables are the dc-link input voltage vector and the angular speed of the inverter output current. The proposed control approach is characterized by satisfactional dynamics and provides enhanced quality of the power transferred to the grid. In the simulation, evaluation of the characteristic operating states of the generator system, correctness of the feedback linearization and the dynamics of active and reactive power control loops are studied. Simulation results are adequately provided.
An Iterative Hybrid Algorithm for Roots of Non-Linear Equations
Authors: Sabharwal Chaman Lal
Published: March 2021

Finding the roots of non-linear and transcendental equations is an important problem in engineering sciences. In general, such problems do not have an analytic solution; the researchers resort to numerical techniques for exploring. We design and implement a three-way hybrid algorithm that is a blend of the Newton–Raphson algorithm and a two-way blended algorithm (blend of two methods, Bisection and False Position). The hybrid algorithm is a new single pass iterative approach. The method takes advantage of the best in three algorithms in each iteration to estimate an approximate value closer to the root. We show that the new algorithm outperforms the Bisection, Regula Falsi, Newton–Raphson, quadrature based, undetermined coefficients based, and decomposition-based algorithms. The new hybrid root finding algorithm is guaranteed to converge. The experimental results and empirical evidence show that the complexity of the hybrid algorithm is far less than that of other algorithms. Several functions cited in the literature are used as benchmarks to compare and confirm the simplicity, efficiency, and performance of the proposed method.
Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Industrial Scale Level
Authors: Barbaccia Pietro , Busetta Gabriele , Matraxia Michele , Sutera Anna Maria , Craparo Valentina , Moschetti Giancarlo , Francesca Nicola , Settanni Luca , Gaglio Raimondo
Published: March 2021

Red grape Nero d’Avola cultivar grape pomace powder (GPP) was applied during fresh ovine cheese production in order to increase polyphenol content. Before cheeses were produced, the bacteria of a freeze-dried commercial starter culture were isolated and tested in vitro against GPP. Two dominant strains, both resistant to GPP, were identified. Thestarter culture was inoculated in pasteurized ewe’s milk and the curd was divided into two bulks, one added with 1% (w/w) GPP and another one GPP-free. GPP did not influence the starter culture development, since lactic acid bacteria (LAB) counts were 109 CFU/g in both cheeses at 30 d. To exclude the interference of indigenous LAB, the pasteurized milk was analyzed, and several colonies of presumptive LAB were isolated, purified and typed. Four strains were allotted into Enterococcus and Lacticaseibacillus genera. The direct comparison of the polymorphic profiles of cheese bacteria evidenced the dominance of the starter culture over milk LAB. The addition of GPP increased cheese total phenolic compounds by 0.42 g GAE/kg. Sensory evaluation indicated that GPP-enriched cheese was well appreciated by the judges, providing evidence that GPP is a suitable substrate to increase the availability of total phenolic content in fresh ovine cheese.
Mechanical Cell Disruption Technologies for the Extraction of Dyes and Pigments from Microorganisms: A Review
Authors: Nemer Georgio , Louka Nicolas , Vorobiev Eugène , Salameh Dominique , Nicaud Jean-Marc , Maroun Richard G. , Koubaa Mohamed
Published: March 2021

The production of pigments using single cell microorganisms is gaining traction as a sustainable alternative to conventional syntheses, which rely, in no negligible proportions, on petrochemicals. In addition to depending on petroleum, these syntheses involved the use of toxic organic solvents, which may be inadequately disposed of across a range of industries, thus compounding the deleterious effects of fossil fuel exploitation. Literature suggests that notable research efforts in the area of sustainable pigment production using single cell microorganisms are focused on the production of pigments coveted for their interesting qualities, which transcend their mere capacity to dye various fabrics both natural and synthetic. As interest in sustainable pigment biosynthesis grows, the need to devise effective and efficient cell disruption processes becomes more pressing given that the viability of pigment biosynthesis is not only dependent on microorganisms’ yield in terms of production, but also on researchers’ ability to recover them. This review chiefly reports findings as to mechanical cell disruption methods, used individually or in various combinations, and their aptitude to recover biosynthetic pigments.
Addendum: Sultana, J., et al. Terahertz Hollow Core Antiresonant Fiber with Metamaterial Cladding. Fibers 2020, 8, 14
Authors: Sultana Jakeya , Islam Md. Saiful , M. B. Cordeiro Cristiano , Dinovitser Alex , Kaushik Mayank , Ng Brian W.-H. , Abbott Derek
Published: March 2021

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