bluuebunny/crossref_metadata_2025 huggingface dataset:
Lymphopenia as a Biological Predictor of Outcomes in COVID-19 Patients: A Nationwide Cohort Study
Authors: Lee Jongmin , Park Sung-Soo , Kim Tong Yoon , Lee Dong-Gun , Kim Dong-Wook
Published: January 2021

We aimed to identify whether lymphopenia is a reliable prognostic marker for COVID-19. Using data derived from a Korean nationwide longitudinal cohort of 5628 COVID-19 patients, we identified propensity-matched cohorts (n = 770) with group I of severe lymphopenia (absolute lymphocyte counts [ALC]: <500/mm3, n = 110), group II of mild-to-moderate lymphopenia (ALC: ≥500–<1000/mm3, n = 330), and group III, no lymphopenia (ALC: ≥1000/mm3, n = 330). A significantly higher mortality rate was associated with lymphopenia severity: 40% in group I, 22.7% in group II, and 13.0% in group III (p < 0.001). At 28 days, the estimated inferior overall survival associated with intensified lymphopenia: 62.7% in group I, 79.9% in group II, and 89.0% in group III (p < 0.001). Lymphopenia contributed significantly toward a greater need for interventions in all groups but at varying degrees: requirements of invasive ventilation, intensive oxygen supply, or adequate oxygen supply, respectively (p < 0.001). The lymphopenia intensity was independently associated with higher COVID-19 mortality in multivariable analysis; adjusted odds ratios of 5.63 (95% CI, 3.0–10.72), and 2.47 (95% CI, 1.5–4.13) for group I and group II, respectively. Lymphopenia and its severity levels may serve as reliable predictive factors for COVID-19 clinical outcomes; thus, lymphopenia may provide the prognostic granularity required for clinical use in the management of patients with COVID-19.
The Interplay of Exosomes and NK Cells in Cancer Biology
Authors: Batista Inês A. , Quintas Sofia T. , Melo Sónia A.
Published: January 2021

Natural killer (NK) cells are innate lymphoid cells involved in tumor surveillance. These immune cells have the potential to fight cancer growth and metastasis, as such, their deregulation can result in tumor immune escape. Recently exosomes were described as mediators of intercellular communication between cancer and NK cells. The exact role of this subclass of extracellular vesicles (EVs), which transport genetic and molecular material to recipient cells, in NK cell biology in the context of cancer, is still an open question. Several reports have demonstrated that tumor-derived exosomes (TDEs) can exert immunomodulatory activities, including immunosuppression, thus promoting cancer progression. Some reports demonstrate that the interplay between cancer exosomes and NK cells allows tumors to escape immune regulation. On the other hand, tumor exosomes were also described to activate NK cells. Additionally, studies show that NK cell exosomes can modulate the immune system, opening up their potential as an immunotherapeutic strategy for cancer treatment. Our review will focus on the reprogramming effect of cancer exosomes on NK cells, and the immunotherapeutic potential of NK cells-derived exosomes.
Lipid Metabolism in Oncology: Why It Matters, How to Research, and How to Treat
Authors: Matsushita Yuki , Nakagawa Hayato , Koike Kazuhiko
Published: January 2021

Lipids in our body, which are mainly composed of fatty acids, triacylglycerides, sphingolipids, phospholipids, and cholesterol, play important roles at the cellular level. In addition to being energy sources and structural components of biological membranes, several types of lipids serve as signaling molecules or secondary messengers. Metabolic reprogramming has been recognized as a hallmark of cancer, but changes in lipid metabolism in cancer have received less attention compared to glucose or glutamine metabolism. However, recent innovations in mass spectrometry- and chromatography-based lipidomics technologies have increased our understanding of the role of lipids in cancer. Changes in lipid metabolism, so-called “lipid metabolic reprogramming”, can affect cellular functions including the cell cycle, proliferation, growth, and differentiation, leading to carcinogenesis. Moreover, interactions between cancer cells and adjacent immune cells through altered lipid metabolism are known to support tumor growth and progression. Characterization of cancer-specific lipid metabolism can be used to identify novel metabolic targets for cancer treatment, and indeed, several clinical trials are currently underway. Thus, we discuss the latest findings on the roles of lipid metabolism in cancer biology and introduce current advances in lipidomics technologies, focusing on their applications in cancer research.
No Impact of NRAS Mutation on Features of Primary and Metastatic Melanoma or on Outcomes of Checkpoint Inhibitor Immunotherapy: An Italian Melanoma Intergroup (IMI) Study
Authors: Guida Michele , Bartolomeo Nicola , Quaglino Pietro , Madonna Gabriele , Pigozzo Jacopo , Di Giacomo Anna , Minisini Alessandro , Tucci Marco , Spagnolo Francesco , Occelli Marcella , Ridolfi Laura , Queirolo Paola , De Risi Ivana , Quaresmini Davide , Gambale Elisabetta , Chiaron Sileni Vanna , Ascierto Paolo , Stigliano Lucia , Strippoli Sabino ,   on behalf of the Italian Melanoma Intergroup (IMI) Study
Published: January 2021

Aims: It is debated whether the NRAS-mutant melanoma is more aggressive than NRAS wildtype. It is equally controversial whether NRAS-mutant metastatic melanoma (MM) is more responsive to checkpoint inhibitor immunotherapy (CII). 331 patients treated with CII as first-line were retrospectively recruited: 162 NRAS-mutant/BRAF wild-type (mut/wt) and 169 wt/wt. We compared the two cohorts regarding the characteristics of primary and metastatic disease, disease-free interval (DFI) and outcome to CII. No substantial differences were observed between the two groups at melanoma onset, except for a more frequent ulceration in the wt/wt group (p = 0.03). Also, the DFI was very similar in the two cohorts. In advanced disease, we only found lung and brain progression more frequent in the wt/wt group. Regarding the outcomes to CII, no significant differences were reported in overall response rate (ORR), disease control rate (DCR), progression free survival (PFS) or overall survival (OS) (42% versus 37%, 60% versus 59%, 12 (95% CI, 7–18) versus 9 months (95% CI, 6–16) and 32 (95% CI, 23–49) versus 27 months (95% CI, 16–35), respectively). Irrespectively of mutational status, a longer OS was significantly associated with normal LDH, <3 metastatic sites, lower white blood cell and platelet count, lower neutrophil-to-lymphocyte (N/L) ratio. Our data do not show increased aggressiveness and higher responsiveness to CII in NRAS-mutant MM.
Regulation of CREB Phosphorylation in Nucleus Accumbens after Relief Conditioning
Authors: Soleimanpour Elaheh , Bergado Acosta Jorge R. , Landgraf Peter , Mayer Dana , Dankert Evelyn , Dieterich Daniela C. , Fendt Markus
Published: January 2021

Relief learning is the association of environmental cues with the cessation of aversive events. While there is increasing knowledge about the neural circuitry mediating relief learning, the respective molecular pathways are not known. Therefore, the aim of the present study was to examine different putative molecular pathways underlying relief learning. To this purpose, male rats were subjected either to relief conditioning or to a pseudo conditioning procedure. Forty-five minutes or 6 h after conditioning, samples of five different brain regions, namely the prefrontal cortex, nucleus accumbens (NAC), dorsal striatum, dorsal hippocampus, and amygdala, were collected. Using quantitative Western blots, the expression level of CREB, pCREB, ERK1/2, pERK1/2, CaMKIIα, MAP2K, PKA, pPKA, Akt, pAkt, DARPP-32, pDARPP-32, 14-3-3, and neuroligin2 were studied. Our analyses revealed that relief conditioned rats had higher CREB phosphorylation in NAC 6 h after conditioning than pseudo conditioned rats. The data further revealed that this CREB phosphorylation was mainly induced by dopamine D1 receptor-mediated activation of PKA, however, other kinases, downstream of the NMDA receptor, may also contribute. Taken together, the present study suggests that CREB phosphorylation, induced by a combination of different molecular pathways downstream of dopamine D1 and NMDA receptors, is essential for the acquisition and consolidation of relief learning.
A Model for the Spread of Infectious Diseases with Application to COVID-19
Authors: Unglaub Ricardo A. G. , Spendier Kathrin
Published: January 2021

Given the present pandemic caused by the severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2 virus, the authors tried fitting existing models for the daily loss of lives. Based on data reported by Worldometers on the initial stages (first wave) of the pandemic for countries acquiring the disease, the authors observed that the logarithmic rendering of their data hinted the response of a first-order process to a step function input, which may be modeled by a three-parameters function, as described in this paper. This model was compared against other similar, log(N)-class of models that are non-compartmental type (such as the susceptible, infected, and removed, or SIR models), obtaining good fit and statistical comparison results, where N denotes the cumulative number of daily presumed deaths. This simple first-order response model can also be applied to bacterial and other biological growth phenomena. Here we describe the model, the numerical methods utilized for its application to actual pandemic data, and the statistical comparisons with other models which shows that our simple model is comparatively outstanding, given its simplicity. While researching the models available, the authors found other functions that can also be applied, with extra parameters, to be described in follow-on articles.
Acknowledgment of Reviewers of Challenges in 2020
Authors:   Challenges Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Challenges maintains its standards for the high quality of its published papers [...]
Understanding Conformational Polymorphism in Ganciclovir: A Holistic Approach
Authors: Spiteri Lorella , Baisch Ulrich , Vella-Zarb Liana
Published: January 2021

We present a holistic crystallographic study of the antiviral ganciclovir, including insights into its solid-state behavior, which could prove useful during drug development, making the process more sustainable. A newly developed methodology was used incorporating a combination of statistical and thermodynamic approaches, which can be applied to various crystalline materials. We demonstrate how the chemical environment and orientation of a functional group can affect its accessibility for participation in hydrogen bonding. The difference in the nature and strength of intermolecular contacts between the two anhydrous forms, exposed through full interaction maps and Hirshfeld surfaces, leads to the manifestation of conformational polymorphism. Variations in the intramolecular geometry and intermolecular interactions of both forms of ganciclovir were identified as possible predictors for their relative thermodynamic stability. It was shown through energy frameworks how the extensive supramolecular network of contacts in form I causes a higher level of compactness and lower enthalpy relative to form II. The likelihood of the material to exhibit polymorphism was assessed through a hydrogen bond propensity model, which predicted a high probability associated with the formation of other relatively stable forms. However, this model failed to classify the stability of form I appropriately, suggesting that it might not have fully captured the collective impacts which govern polymorphic stability.
Acknowledgment to Reviewers of Chemistry in 2020
Authors:   Chemistry Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Chemistry maintains its standards for the high quality of its published papers [...]
Acknowledgment to Reviewers of Clean Technologies in 2020
Authors:   Clean Technologies Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Clean Technologies maintains its standards for the high quality of its published papers [...]
Testing New Coatings for Outdoor Bronze Monuments: A Methodological Overview
Authors: Letardi Paola
Published: January 2021

Coatings to be used for cultural heritage protection face peculiar challenges. In the last few decades, several projects addressed the issue of new treatments in the field of copper alloy artworks. Nonetheless, no one has yet been recognised as a more acceptable solution with respect to traditional choices, with their known limits. The lack of standard methods to test new coatings that can be effectively applied to artworks make it more difficult to compare different studies and open the way to practical use in restoration. Over the years, several issues have gradually been better focused, even though they are not yet widely considered in new coatings efficacy evaluation for application on copper alloy artifacts. They are mainly linked to the quite complex surface of this category of heritage objects and the role it plays on coating effectiveness. An overview of the variety of relevant surface properties is provided (presence of corrosion products and old protective treatments, cleaning methods, surface unevenness, just to name a few) with a special focus on the role of coating performance. Some methodological choices are discussed for the selection of mock-ups, testing techniques and weathering procedures, with peculiar attention to comparison with real artworks.
Effect of Pressure on the Film Deposition during RF Magnetron Sputtering Considering Charged Nanoparticles
Authors: Kim Du-Yun , Kwon Ji-Hye , Jang Gil-Su , Hwang Nong-Moon
Published: January 2021

Non-classical crystallization, in which charged nanoparticles (NPs) are the building blocks of film growth, has been extensively studied in chemical vapor deposition (CVD). Recently, a similar mechanism of film growth has been reported during radio frequency (RF) sputtering with a Ti target and DC magnetron sputtering using an Ag target. In this study, the effect of pressure on the generation of Ti NPs and on the film deposition was studied during RF sputtering with a Ti target. Ti NPs were captured on transmission electron microscopy (TEM) membranes with the electric biases of −30, 0, and +50 V under 20 and 80 mTorr. The number densities of the Ti NPs were 134, 103, and 21 per 100 × 100 nm2, respectively, with the biases of −30, 0, and +50 V under 20 mTorr and were 196, 98, and 0 per 100 × 100 nm2, respectively, with the biases of −30, 0, and +50 V under 80 mTorr, which was analyzed by TEM. The growth rate of Ti films deposited on Si substrates was insensitive to the substrate bias under 20 mTorr but was sensitive under 80 mTorr, with the thicknesses of 132, 133, 97, and 29 nm, respectively, after being deposited for 15 min with the substrate biases of −30, −10, 0, and +50 V. This sensitive dependence of the film growth rate on the substrate bias under 80 mTorr is in agreement with the sensitive dependence of the number density of Ti NPs on the substrate bias under 80 mTorr.
Field Electron Emission Experiments with Cold-Sprayed Cu-SiC Composite Coatings
Authors: Winnicki Marcin , Łapa Wojciech , Znamirowski Zbigniew
Published: January 2021

Field electron emission of cold-sprayed copper-silicon carbide composite coating on a steel substrate was investigated. Two types of copper powders morphologies, namely dendritic and spherical, were mixed with crushed silicon carbide ceramic, and used as a feedstock. The powder mixtures were sprayed on the substrates and formed coatings with the designed surface topography—(i) flat and (ii) wavy. The microstructure of the coatings as well as the ceramic contents were analyzed. Initial tests proved that field emission from the Cu-SiC composite coatings was possible and depended mostly on the copper powder morphology. It was found out that the additional SiC layer deposited onto the composite coating significantly increased the number of electron emitters and thus improved the intensity of field emission. The Fowler–Nordheim model was used to find the threshold electric field, Eth, and coefficient of electric field amplification, β. These important properties of Cu/SiC + SiC coatings were found to be in the range of Eth = 20 to 24 V/µm and β = 340 to 410, respectively.
Enhancing the Optical Efficiency of Near-Eye Displays with Liquid Crystal Optics
Authors: Zhan Tao , Hsiang En-Lin , Li Kun , Wu Shin-Tson
Published: January 2021

We demonstrate a light efficient virtual reality (VR) near-eye display (NED) design based on a directional display panel and a diffractive deflection film (DDF). The DDF was essentially a high-efficiency Pancharatnam-Berry phase optical element made of liquid crystal polymer. The essence of this design is directing most of the display light into the eyebox. The proposed method is applicable for both catadioptric and dioptric VR lenses. A proof-of-concept experiment was conducted with off-the-shelf optical parts, where the light efficiency was enhanced by more than 2 times.
Synthesis, Characterization, Single-Crystal X-ray Structure and Biological Activities of [(Z)-N′-(4-Methoxybenzylidene)benzohydrazide–Nickel(II)] Complex
Authors: Al-Qadsy Inas , Al-Odayni Abdel-Basit , Saeed Waseem Sharaf , Alrabie Ali , Al-Adhreai Arwa , Al-Faqeeh Lena Ahmed Saleh , Lama Prem , Alghamdi Abdulaziz Ali , Farooqui Mazahar
Published: January 2021

(Z)-N′-(4-methoxybenzylidene)benzohydrazide (HL) and its Ni(II) complex (Ni(II)-2L) were synthesized using eco-friendly protocols. The single X-ray crystal structure of Ni(II)-2L was solved. Moreover, the structural properties were evaluated using Fourier transform infrared, proton nuclear magnetic resonance, mass, and Ultraviolet/Visible spectroscopy. The diamagnetic and thermal stability were assessed using magnetic susceptibility and thermogravimetric analysis, respectively. The biological activities of both HL and Ni(II)-2L (62.5–1000 μg/mL) against Gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial and fungal (Candida albicans, Aspergillus niger, and Aspergillus clavatus) species were studied using the minimum inhibitory concentration (MIC) tests method in reference to Gentamycin and Nystatin standard drugs, respectively. The results revealed an affordable, environmentally friendly, and efficient synthetic method of HL using water as a green solvent. The Ni(II)-2L complex crystallized in a distorted square planar, P21/n space group, and one Ni(II) to two bidentate negatively charged ligand ratio. The analysis of biological activity revealed higher activity of the complex against S. aureus and S. pyogenes (bacteria) and A. niger and A. clavatus (fungi) compared to the ligand. However, the highest activity was at a MIC of 62.5 μg/mL for the complex against S. pyogenes and for the ligand against E. coli. Therefore, both HL and Ni(II)-2L could be promising potential antimicrobials and their selective activity could be an additional benefit of these bioactive materials.
Role of Halogen Substituents on Halogen Bonding in 4,5-DiBromohexahydro-3a,6-Epoxyisoindol-1(4H)-ones
Authors: Gurbanov Atash , Mertsalov Dmitriy , Zubkov Fedor , Nadirova Maryana , Nikitina Eugeniya , Truong Hieu , Grigoriev Mikhail , Zaytsev Vladimir , Mahmudov Kamran , Pombeiro Armando
Published: January 2021

A series of 4,5-dibromo-2-(4-substituted phenyl)hexahydro-3a,6-epoxyisoindol-1(4H)-ones were synthesized by reaction of the corresponding 2-(4-substituted phenyl)-2,3,7,7a-tetrahydro-3a,6-epoxyisoindol-1(6H)-ones with [(Me2NCOMe)2H]Br3 in dry chloroform under reflux for 3−5 h. In contrast to the 4-F and 4-Cl substituents, one of the bromine atoms of the isoindole moiety behaves as a halogen bond donor in the formation of intermolecular halogen bonding in the 4-H, 4-Br and 4-I analogues. Not only intermolecular hydrogen bonds, but also Ha⋯Ha and Ha⋯π types of halogen bonds in the 4-H, 4-Br, and 4-I compounds, contribute to the formation of supramolecular architectures leading to 2D or 3D structures.
The Relative Contribution of Solutal Marangoni Convection to Thermal Marangoni Flow Instabilities in a Liquid Bridge of Smaller Aspect Ratios under Zero Gravity
Authors: Agampodi Mendis Radeesha Laknath , Sekimoto Atsushi , Okano Yasunori , Minakuchi Hisashi , Dost Sadik
Published: January 2021

The effect of solutal Marangoni convection on flow instabilities in the presence of thermal Marangoni convection in a Si-Ge liquid bridge with different aspect ratios As has been investigated by three-dimensional (3D) numerical simulations under zero gravity. We consider a half-zone model of a liquid bridge between a cold (top plane) and a hot (bottom plane) disks. The highest Si concentration is on the top of the liquid bridge. The aspect ratio (As) drastically affects the critical Marangoni numbers: the critical solutal Marangoni number (under small thermal Marangoni numbers (MaTAs≲1800)) has the same dependence on As as the critical thermal Marangoni number (under small solutal Marangoni numbers (400≲MaCAs≲800)), i.e., it decreases with increasing As. The azimuthal wavenumber of the traveling wave mode increases as decreasing As, i.e., larger azimuthal wavenumbers (m=6,7,11,12, and 13) appear for As=0.25, and only m=2 appears when As is one and larger. The oscillatory modes of the hydro waves have been extracted as the spatiotemporal structures by using dynamic mode decomposition (DMD). The present study suggests a proper parameter region of quiescent steady flow suitable for crystal growth for smaller aspect ratios of the liquid bridge.
One-Pot Microwave-Assisted Synthesis of Water-Soluble Pyran-2,4,5-triol Glucose Amine Schiff Base Derivative: XRD/HSA Interactions, Crystal Structure, Spectral, Thermal and a DFT/TD-DFT
Authors: Hijji Yousef , Rajan Rajeesha , Ben Yahia Hamdi , Mansour Said , Zarrouk Abdelkader , Warad Ismail
Published: January 2021

The(3R,4R,6R)-3-(((E)-2-hydroxybenzylidene)amino)-6-(hydroxymethyl)tetrahydro-2H-pyran-2,4,5-triol water-soluble Glucose amine Schiff base (GASB-1) product was made available by condensation of 2-hydroxybenzaldehyde with (3R,6R)-3-amino-6-(hydroxymethyl)-tetra-hydro-2H-pyran-2,4,5-triol under mono-mode microwave heating. A one-pot 5-minute microwave-assisted reaction was required to complete the condensation reaction with 90% yield and without having byproducts. The 3D structure of GASB-1 was solved from single crystal X-ray diffraction data and computed by DFT/6-311G(d,p). The Hirshfeld surface analysis (HSA), molecular electronic potential (MEP), Mulliken atomic charge (MAC), and natural population analysis (NPA) were performed. The IR and UV-Vis spectra were matched to their density functional theory (DFT) relatives and the thermal behavior was resolved in an open-room condition via thermogravimetry/Derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC). The highest occupied molecular orbital/lowest unoccupied molecular orbital (HOMO/LUMO), density of state (DOS), and time-dependence TD-DFT computations were correlated to the experimental electron transfer in water and acrylonitrile solvents.
Electrical Properties Tomography: A Methodological Review
Authors: Leijsen Reijer , Brink Wyger , van den Berg Cornelis , Webb Andrew , Remis Rob
Published: January 2021

Electrical properties tomography (EPT) is an imaging method that uses a magnetic resonance (MR) system to non-invasively determine the spatial distribution of the conductivity and permittivity of the imaged object. This manuscript starts by providing clear definitions about the data required for, and acquired in, EPT, followed by comprehensively formulating the physical equations underlying a large number of analytical EPT techniques. This thorough mathematical overview of EPT harmonizes several EPT techniques in a single type of formulation and gives insight into how they act on the data and what their data requirements are. Furthermore, the review describes machine learning-based algorithms. Matlab code of several differential and iterative integral methods is available upon request.
Improving the Accuracy of Nearest-Neighbor Classification Using Principled Construction and Stochastic Sampling of Training-Set Centroids
Authors: Whitelam Stephen
Published: January 2021

A conceptually simple way to classify images is to directly compare test-set data and training-set data. The accuracy of this approach is limited by the method of comparison used, and by the extent to which the training-set data cover configuration space. Here we show that this coverage can be substantially increased using coarse-graining (replacing groups of images by their centroids) and stochastic sampling (using distinct sets of centroids in combination). We use the MNIST and Fashion-MNIST data sets to show that a principled coarse-graining algorithm can convert training images into fewer image centroids without loss of accuracy of classification of test-set images by nearest-neighbor classification. Distinct batches of centroids can be used in combination as a means of stochastically sampling configuration space, and can classify test-set data more accurately than can the unaltered training set. On the MNIST and Fashion-MNIST data sets this approach converts nearest-neighbor classification from a mid-ranking- to an upper-ranking member of the set of classical machine-learning techniques.
Clustering of Load Profiles of Residential Customers Using Extreme Points and Demographic Characteristics
Authors: Jeong Hyun Cheol , Jang Minseok , Kim Taegon , Joo Sung-Kwan
Published: January 2021

In this paper, a systematic method is proposed to cluster the energy consumption patterns of residential customers by utilizing extreme points and demographic characteristics. The extreme points of the energy consumption pattern enable effective clustering of residential customers. Additionally, demographic characteristics can be used to determine an effective extreme point for the clustering algorithm. The K-means-based features selection method is used to classify energy consumption patterns of residential customers into six types. Furthermore, the type of energy consumption pattern can be identified depending on the characteristics of residential customers. The analytical results of this paper show that the extreme points are effective in clustering the energy consumption patterns of residential customers.
Electric Field Sensing with a Modified SRR for Wireless Telecommunications Dosimetry
Authors: Vazquez Fabian , Villareal Alejandro , Rodriguez Alfredo , Martin Rodrigo , Solis-Najera Sergio , Melendez Oscar Rene Marrufo
Published: January 2021

Split ring resonators (SRRs) have been used extensively in metamaterials, showing a strong localization and enhancement of fields, which significantly improves the sensitivity and resolution of the electromagnetic field sensors. We propose the development of an electric field sensor for 2.4 GHz industrial, scientific, and medical (ISM) band applications, by modifying the renowned SRR to contain three concentric pairs of rings. The reduced size makes the sensor affordable for experiments by inserting it in phantoms in order to measure the specific absorption rate (SAR). Power was transmitted from a patch antenna to SRR, with a varying set of distances 1λ, 2λ, 3λ, or 5λ. Experimental measurements of power were conducted with and without a cylindrical distilled-water phantom with agar (4.54%) and NaCl (0.95%). We then computed the electric and magnetic fields and the SAR using these experimental readings of power for different distances. Our sensor was able to measure power values from 20 nW to 0.3 µW with no phantom, and 1 nW to 10 nW with a phantom, in accordance with the values reported for radiofrequency (RF) dosimetry. The sensitivity as a function of the distance determined for the specific case of a phantom was 0.3 µW/cm.
A Study on Core Skew Considering Manufacturability of Double-Layer Spoke-Type PMSM
Authors: Nam Dong-Woo , Lee Kang-Been , Pyo Hyun-Jo , Jeong Min-Jae , Yang Seo-Hee , Kim Won-Ho , Jang Hyung-Kwan
Published: January 2021

The spoke-type permanent magnet synchronous motor (PMSM), which is a general ferrite magnetic flux-concentrated motor, has a low portion of reluctance torque at the total torque magnitude. Therefore, as a way to increase the reluctance torque, there is a double-layer spoke-type PMSM that can maximize the difference in inductance between the d-axis and the q-axis. However, in the double-layer spoke-type PMSM, cogging torque, torque ripple, and total harmonic distortion (THD) increase with reluctance torque, which is the main cause of vibration and noise. In this paper, a method is proposed that provides the same effect as skew without dividing stages of the permanent magnet by dividing the core of the rotor into two types so that it is easy to manufacture according to the number of stages, unlike extant skew methods. Based on the method, the reduction in cogging torque and THD was verified by finite element analysis (FEA).
Fixed Transmission Charges Based on the Degree of Network Utilization
Authors: Korab Roman , Kocot Henryk , Majchrzak Henryk
Published: January 2021

The core objective of transmission tariffs is the recovery of costs related to the transport of electricity. A usual component of a tariff is a fixed charge that covers the costs of the network infrastructure. As many customers use the power grid, the rate of this charge should reflect, as closely as possible, the actual costs of supplying energy to the individual consumers. These costs result from which network elements have been used in delivering the electricity, and to what extent these elements have been used. Therefore, the fixed transmission rates should depend on the degree of network utilization. This article investigates definitions of the degree of network utilization based on the active power flow. To calculate the degree of network utilization, the flow of electricity on a branch must be decomposed into the streams flowing to individual customers. For this decomposition, two methods are examined: a power flow tracing method, based on the proportional sharing principle, and an incremental power flow method, based on the superposition principle. The analyzed methodology is applied to a small test system for conceptual discussions, as well as to the transmission network of the Polish power system, as an example of practical application. The results of this study were then compared with the commonly used “postage stamp” method. Finally, several practical aspects related to the potential implementation of the presented methodology are discussed.
Corrosion Repair of Pipelines Using Modern Composite Materials Systems: A Numerical Performance Evaluation
Authors: Dumitrescu Andrei , Minescu Mihail , Dinita Alin , Lambrescu Ionut
Published: January 2021

Pipe corrosion is a frequent phenomenon, and if repairs are delayed it could lead to environmental damage. Drilling activities can expand only when sufficient surface transportation capacity for the produced fluids exists and thus good maintenance of the transportation system is important. Furthermore, the technology presented herein can be easily upgraded as a repair solution for surface casing section below the casing head, which have been repeatedly reported as being highly corroded for older wells. This paper presents the results of the research work carried out by the authors in order to evaluate the design methods of the modern composite material systems used to repair steel pipes carrying hydrocarbons upon which local metal loss defects (generated by corrosion and/or erosion processes) have been detected. The pipe repair technologies consisting of the application of composite material wraps (made of a polymeric matrix and reinforcing fabric) are perceived as being advantageous alternative solutions for substituting the conventional technologies, which require welding operations to be performed in the corroded pipe areas. The performance and the design methods of the composite repair systems have been investigated by evaluating the reinforcement effects (the restoration level of the damaged pipe mechanical strength) generated by the applied composite wraps as a function of their geometry and mechanical properties. To that purpose, numerical models based on finite elements (previously developed by the authors and certified by comparing them with the results of several experimental programs performed within our university) have been used. The calculation methods proposed in literature (among which a method previously proposed by the authors) to define the composite wrap dimensions (thickness and length) for a given pipe have been compared to the numerical results in order to select the most adequate solution for the design of the composite repair system. The influence in the design process of the defect orientation and of its width has also been investigated.
Ranking the Key Forest Habitats in Ecosystem Function Provision: Case Study from Morava River Basin
Authors: Pechanec Vilém , Machar Ivo , Kilianová Helena , Vyvlečka Pavel , Seják Josef , Pokorný Jan , Štěrbová Lenka , Prokopová Marcela , Cudlín Pavel
Published: January 2021

Floodplain forests are considered important forest ecosystems, and providers of ecosystem functions and services. The subject of this research was to assess the level of provision of five selected ecosystem functions (climate regulation and regulation of short water cycle, biomass production, oxygen production, and carbon sequestration) and biodiversity by relevant groups of forest habitats, and their mutual comparison. Assessment of ecosystem functions was performed in biophysical units based on published data, our own research, and expert knowledge. The results showed the high importance of floodplain forests. In the majority of the services that were studied, this habitat reached high values and, in comparison with the other habitats, took one of the leading positions. When comparing the ranking in the provision of individual ecosystem functions per unit area, the best-assessed habitat in all assessed functions was floodplain and wetland forests, followed by ravine forests and beech forests, but the analysis of the rate of ecosystem function provision, related to the total area of interest, showed a different order of values. Understanding the context of the individual ecosystem functions of natural ecosystems and those close to nature, in comparison with anthropogenically altered ecosystems is a suggested route for ecologically and economically balanced landscape decision-making, which may increase the efficiency of nature and landscape protection.
Assessment of Wooden Foundation Piles after 125 Years of Service
Authors: Humar Miha , Balzano Angela , Kržišnik Davor , Lesar Boštjan
Published: January 2021

Buildings on piles have been constructed in Ljubljana since the Bronze Age. The piles were made of different types of wood. In the present study, piles that were erected about 125 years ago were investigated. Investors tend to renovate a building; therefore, the piles were analysed to assess the structural condition of the building. The building showed no signs of damage. To gain access to the piles, a 2 m thick layer of soil was removed. On-site, the following analyses were carried out: drilling resistance with a resistograph and a screw withdrawal test. Part of the piles was isolated and light microscopy, scanning electron microscopy, infrared spectroscopy, dynamic vapour sorption, density analysis, and chemical analysis were performed. Microscopic analysis revealed that the piles were made from the wood of Scots pine (Pinus sylvestris). The results indicate that the wood was severely degraded, mainly by soft-rot fungi and bacteria, resulting in a significant deterioration of its mechanical properties.
Experimental Characterization of the Heat Transfer in Multi-Microchannel Heat Sinks for Two-Phase Cooling of Power Electronics
Authors: Criscuolo Gennaro , Brix Markussen Wiebke , Meyer Knud Erik , Palm Björn , Ryhl Kærn Martin
Published: January 2021

This study aims to characterize experimentally the heat transfer in micro-milled multi-microchannels copper heat sinks operating with flow boiling, in the attempt to contribute to the development of novel and high heat flux thermal management systems for power electronics. The working fluid was R-134a and the investigation was conducted for a nominal outlet saturation temperature of 30 ∘C. The microchannels were 1 cm long and covered a square footprint area of 1 cm2. Boiling curves starting at low vapor quality and average heat transfer coefficients were obtained for nominal channel mass fluxes from 250 kg/m2s to 1100 kg/m2s. The measurements were conducted by gradually increasing the power dissipation over a serpentine heater soldered at the bottom of the multi-microchannels, until a maximum heater temperature of 150 ∘C was reached. Infrared thermography was used for the heater temperature measurements, while high-speed imaging through a transparent top cover provided visual access over the entire length of the channels. The average heat transfer coefficient increased with the dissipated heat flux until a decrease dependent on hydrodynamic effects occurred, possibly due to incomplete wall wetting. Depending on the channel geometry, a peak value of 200 kW/m2K for the footprint heat transfer coefficient and a maximum dissipation of 620 W/cm2 at the footprint with a limit temperature of 150 ∘C could be obtained, showing the suitability of the investigated geometries in high heat flux cooling of power electronics. The experimental dataset was used to assess the prediction capability of selected literature correlations. The prediction method by Bertsch et al. gave the best agreement with a mean absolute percent error of 24.5%, resulting to be a good design tool for flow boiling in high aspect ratio multi-microchannels as considered in this study.
Purchase Intention for Organic Food Products in Mexico: The Mediation of Consumer Desire
Authors: Leyva-Hernández Sandra N. , Toledo-López Arcelia , Hernández-Lara Ana B.
Published: January 2021

Socially responsible consumption benefits the environment, the consumer, and the producer. In Mexico, smallholder farmers are vulnerable, and the consumption of organic food products is low. Analysing the purchase intention of organic food products contributes towards generating the most appropriate marketing strategies. Previous models provide evidence that the attitude of the consumer is the biggest predictor of purchase intention. However, little is known about the results of the mediating effect of desire on said relationship. The objective of the study is to analyse the mediating effect of desire on the relationship between attitude and purchase intention. 204 consumers of organic food products were surveyed using a structured, self-administrated questionnaire or through face-to-face interviews, in established retail stores, alternative street markets, and via the web. It was found that when the benefits of organic food products to the consumer, environment, and smallholder farmers are evaluated favourably, then consumer desire is higher, and thus also purchase intention. Consumers have the highest purchase intention for organic food products when their desire to buy them to achieve a goal related with social, personal, and environmental benefits intervenes.
Bioactivity of Hydrolysates Obtained from Chicken Egg Ovalbumin Using Artichoke (Cynara scolymus L.) Proteases
Authors: Bueno-Gavilá Estefanía , Abellán Adela , Girón-Rodríguez Francisco , Cayuela José María , Tejada Luis
Published: January 2021

The aim of this work was to obtain chicken egg ovalbumin hydrolysates using aspartic proteinases present in extracts from the artichoke flower (Cynara scolymus L.) and evaluate their antioxidant, antimicrobial, and angiotensin I-converting enzyme (ACE) inhibitory activity in vitro. Hydrolysis time and molecular weight (<3 kDa) had a significant influence on the hypertensive and antioxidant activity of the hydrolysates. The <3 kDa fraction of the 16 h hydrolysate had an ACE inhibitory activity with an IC50 of 64.06 µg peptides/mL. The fraction <3 kDa of ovalbumin hydrolysate at 2 h of hydrolysis showed a DPPH radical scavenging activity of 30.27 µM of Trolox equivalents/mg peptides. The fraction <3 kDa of the hydrolysate of 16 h had an ABTS+ caption activity of 4.30 mM of Trolox equivalents/mg peptides. The fraction <3 kDa of the hydrolysate of 2 h had an iron (II) chelating activity of 32.18 µg peptides/mL. From the peptide sequences identified in the hydrolysates, we detected four peptides (from the BIOPEP database) that were already in their bioactive form (IAAEVYEHTEGSTTSY, HLFGPPGKKDPV, PIAAEVYEHTEGSTTSY, and YAEERYPIL), and are reported to display antioxidant and ACE inhibitory activity.
Quantum Noise in a Fabry-Perot Interferometer Including the Influence of Diffraction Loss of Light
Authors: Iwaguchi Shoki , Ishikawa Tomohiro , Ando Masaki , Michimura Yuta , Komori Kentaro , Nagano Koji , Akutsu Tomotada , Musha Mitsuru , Yamada Rika , Watanabe Izumi , Naito Takeo , Morimoto Taigen , Kawamura Seiji
Published: January 2021

The DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is designed to detect gravitational waves at frequencies between 0.1 and 10 Hz. In this frequency band, one of the most important science targets is the detection of primordial gravitational waves. DECIGO plans to use a space interferometer with optical cavities to increase its sensitivity. For evaluating its sensitivity, diffraction of the laser light has to be adequately considered. There are two kinds of diffraction loss: leakage loss outside the mirror and higher-order mode loss. These effects are treated differently inside and outside of the Fabry-Perot (FP) cavity. We estimated them under the conditions that the FP cavity has a relatively high finesse and the higher-order modes do not resonate. As a result, we found that the effects can be represented as a reduction of the effective finesse of the cavity with regard to quantum noise. This result is useful for optimization of the design of DECIGO. This method is also applicable to any FP cavities with a relatively small beam cut and the finesse sufficiently higher than 1.
Distinguishing Racism, Not Race, as a Risk Factor for Child Welfare Involvement: Reclaiming the Familial and Cultural Strengths in the Lived Experiences of Child Welfare-Affected Parents of Color
Authors: Stephens Tricia N.
Published: January 2021

Child welfare-affected parents of color (CW-PaoC) are often described using language that is deficit-focused, their families depicted as fragile and living in a near constant state of crisis and need. This commentary challenges the stereotypes created by hyper-attention to these parents’ struggles and situates them, and their families, within the broader context of the American appetite for family separation, wherein specific types of families are targeted for scrutiny, intervention and regulation. The concept of fragility within families is dissected to illustrate the ways in which racism and classism demarcate certain families for separation. Excerpts from two separate interviews conducted with Black mothers in 2014 and 2020 are used to illustrate how the appetite for family separation is currently fed. Familial and cultural strengths that counteract the prevailing deficit-focused narrative of CW-PaoC, particularly Black parents, are discussed. This commentary ends with a call for the dissolution of the CW system in its current regulatory form and the rebuilding of family-centered supports that center familial strengths.
A New Perspective on the Origin of DNA Double-Strand Breaks and Its Implications for Ageing
Authors: Tripathy Bhabesh Kumar , Pal Kavita , Shabrish Snehal , Mittra Indraneel
Published: January 2021

It is estimated that 10–50 DNA double-strand breaks (DSBs) occur in a nucleated human cell per cell cycle. We reviewed the present state of knowledge and hypothesized that the currently accepted mechanisms cannot explain such high frequency of DSBs occurring daily under normal physiological conditions. We propose an alternative model that implicates illegitimate genomic integration into healthy cells of cell-free chromatin (cfCh) particles released from the billions of cells that die in the body every day. Repeated genomic integration of cfCh may have catastrophic consequences for the cell, such as DSBs, their faulty repair by nonhomologous end joining (NHEJ) followed by apoptosis with release of more cfCh which would integrate into genomes of surrounding cells. This can creates a vicious cycle of cfCh integration, DSBs, NHEJ, and more apoptosis, thereby providing a potential explanation as to why so many billions of cells die in the body on a daily basis. We also recount the recent observation that cfCh integration and the resulting DSBs activate inflammatory cytokines. This leads us to propose that concurrent DSBs and induction of inflammation occurring throughout life may be the underlying cause of ageing, degenerative disorders, and cancer. Finally, we discuss the prospect that agents that can inactivate/degrade cfCh may hold the key to making healthy ageing a realizable goal.
Acknowledgment to Reviewers of Geriatrics in 2020
Authors:   Geriatrics Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Geriatrics maintains its standards for the high quality of its published papers [...]
Acknowledgment to Reviewers of Heritage in 2020
Authors:   Heritage Editorial Office
Published: January 2021

Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Heritage maintains its standards for the high quality of its published papers [...]
Investigating the Geographic Disparities of Amenable Mortality and Related Ambulance Services in Hungary
Authors: Deák Máté Sándor , Csató Gábor , Pápai György , Dombrádi Viktor , Nagy Attila , Nagy Csilla , Juhász Attila , Bíró Klára
Published: January 2021

The aim of this study was to investigate how amenable mortality and related ambulance services differ on a county level in Hungary. The differences in mortality rates and ambulance services could identify counties where stronger ambulance services are needed. The datasets for 2018 consisted of county level aggregated data of citizens between the ages 15–64. The study examined how both the mortality rates and the ambulance rescue deliveries differ from the national average. The analyses were narrowed down to disease groups, such as acute myocardial infarction, hemorrhagic and ischemic stroke. Inequalities were identified regarding the distribution of number of ambulance deliveries, several counties had rates more than double that of the national average. For both mortality and ambulance services some of the counties had significantly better results and others had significantly worse compared to the national average. In Borsod-Abaúj-Zemplén county’s case, hemorrhagic stroke mortality was significantly higher (1.73 [1.35–2.11]), while ambulance deliveries were significantly lower (0.58 [0.40–0.76]) compared to the national average. The research has shown that regarding the investigated mortality rates and ambulance services there are considerable differences between the counties in Hungary. In this regard policy makers should implement policies to tackle these discrepancies.