bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduction of 5G cellular network radiation in wireless mobile phone using an asymmetric square shaped passive metamaterial design
Authors: Ramachandran Tayaallen , Faruque Mohammad Rashed Iqbal , Siddiky Air Mohammad , Islam Mohammad Tariqul 
Published: January 2021

AbstractThis study aims to demonstrate the feasibility of metamaterial application in absorption reduction of 5G electromagnetic (EM) energy in the human head tissue. In a general sense, the radio frequency (RF) energy that received by wireless mobile phone from the base station, will emit to surrounding when the devices are in active mode. Since the latest fifth generation technology standard for cellular networks is upon us, the emission of radiation from any wireless devices needs to be taken into consideration. This motivation helps to prepare this paper that focuses on construction of novel and compact square-shaped metamaterial (SM) design to reduce electromagnetic exposure to humans. The commercially available substrate material known as FR-4 with thickness of 1.6 mm was selected to place the metamaterial design on it. The electromagnetic properties and Specific Absorption Rate (SAR) analyses were carried out numerically by utilising high-performance 3D EM analysis, Computer Simulation Technology Studio (CST) software. Meanwhile, for the validation purpose, the metamaterial designs for both unit and array cells were fabricated to measure the electromagnetic properties of the material. From the numerical simulation, the introduced SM design manifested quadruple resonance frequencies in multi bands precisely at 1.246 (at L-band), 3.052, 3.794 (at S-band), and 4.858 (C-band) GHz. However, the comparison of numerically simulated and measured data reveals a slight difference between them where only the second resonance frequency was decreased by 0.009 GHz while other frequencies were increased by 0.002, 0.045, and 0.117 GHz in sequential order. Moreover, the SAR analysis recorded high values at 3.794 GHz with 61.16% and 70.33% for 1 g and 10 g of tissue volumes, respectively. Overall, our results demonstrate strong SAR reduction effects, and the proposed SM design may be considered a promising aspect in the telecommunication field.
Ethnicity influences the gut microbiota of individuals sharing a geographical location: a cross-sectional study from a middle-income country
Authors: Dwiyanto Jacky , Hussain M. H. , Reidpath D. , Ong K. S. , Qasim A. , Lee S. W. H. , Lee S. M. , Foo S. C. , Chong C. W. , Rahman Sadequr 
Published: January 2021

AbstractNo studies have investigated the influence of ethnicity in a multi-ethnic middle-income country with a long-standing history of co-habitation. Stool samples from 214 Malaysian community members (46 Malay, 65 Chinese, 49 Indian, and 54 Jakun) were collected. The gut microbiota of the participants was investigated using 16S amplicon sequencing. Ethnicity exhibited the largest effect size across participants (PERMANOVA Pseudo-F = 4.24, R2 = 0.06, p = 0.001). Notably, the influence of ethnicity on the gut microbiota was retained even after controlling for all demographic, dietary factors and other covariates which were significantly associated with the gut microbiome (PERMANOVA Pseudo-F = 1.67, R2 = 0.02, p = 0.002). Our result suggested that lifestyle, dietary, and uncharacterized differences collectively drive the gut microbiota variation across ethnicity, making ethnicity a reliable proxy for both identified and unidentified lifestyle and dietary variation across ethnic groups from the same community.
FANCD2 modulates the mitochondrial stress response to prevent common fragile site instability
Authors: Fernandes Philippe , Miotto Benoit , Saint-Ruf Claude , Said Maha , Barra Viviana , Nähse Viola , Ravera Silvia , Cappelli Enrico , Naim Valeria 
Published: January 2021

AbstractCommon fragile sites (CFSs) are genomic regions frequently involved in cancer-associated rearrangements. Most CFSs lie within large genes, and their instability involves transcription- and replication-dependent mechanisms. Here, we uncover a role for the mitochondrial stress response pathway in the regulation of CFS stability in human cells. We show that FANCD2, a master regulator of CFS stability, dampens the activation of the mitochondrial stress response and prevents mitochondrial dysfunction. Genetic or pharmacological activation of mitochondrial stress signaling induces CFS gene expression and concomitant relocalization to CFSs of FANCD2. FANCD2 attenuates CFS gene transcription and promotes CFS gene stability. Mechanistically, we demonstrate that the mitochondrial stress-dependent induction of CFS genes is mediated by ubiquitin-like protein 5 (UBL5), and that a UBL5-FANCD2 dependent axis regulates the mitochondrial UPR in human cells. We propose that FANCD2 coordinates nuclear and mitochondrial activities to prevent genome instability.
Assessment of risk factors for postoperative cognitive dysfunction after coronary artery bypass surgery: a single-center retrospective cohort study
Authors: Sun Yongtao , Feng Hai , Zou Ting , Hou Ming , Jin Yanwu , Gu Changping , Wang Yuelan , Li Juan , Liu Mengjie , Zhang Min , Gao Yalei 
Published: January 2021

Abstract
Aim: To find out risk factors for postoperative cognitive dysfunction (POCD) after coronary artery bypass grafting (CABG), and to provide basis for clinical prevention of POCD. A total of 88 patients who underwent CABG were surveyed with Telephone Questionnaire (TICS-M) for their cognitive impairment after 3, 7, 21, 90, 180 days post-surgery. The occurrence of POCD was diagnosed by Neuropsychological Battery which included Vocabular Learning Test (VLT), Wisconsin Card Sorting Test (WCST), Trail Making Test (TMT) and Symbol Digit Modalities Test (SDMT). The preoperative, intraoperative and postoperative risk factors were assessed by the χ2 or t test. Multivariate analysis was used to study the correlation between the risk factors and the occurrence of POCD. Age, aortic plaque, carotid artery stenosis, cerebrovascular disease, anesthesia time, the rate of decline in intraoperative hemoglobin concentration (ΔHb) and systemic inflammatory response syndrome (SIRS) score on postoperative day 2 had statistically significant (P&lt;0.05) influence on the occurrence of POCD. Aortic plaque, carotid artery stenosis, anesthesia time and SIRS score (odds ratio (OR) value &gt; 1, P&lt;0.05) are the risk factors for POCD. The incidence of day-21 and -180 POCD was approximately 26.1 and 22.7%, respectively.
ACE2/Ang-(1-7)/Mas1 axis and the vascular system: vasoprotection to COVID-19-associated vascular disease
Authors: Kuriakose Jithin , Montezano Augusto C. , Touyz Rhian M. 
Published: January 2021

AbstractThe two axes of the renin–angiotensin system include the classical ACE/Ang II/AT1 axis and the counter-regulatory ACE2/Ang-(1-7)/Mas1 axis. ACE2 is a multifunctional monocarboxypeptidase responsible for generating Ang-(1-7) from Ang II. ACE2 is important in the vascular system where it is found in arterial and venous endothelial cells and arterial smooth muscle cells in many vascular beds. Among the best characterized functions of ACE2 is its role in regulating vascular tone. ACE2 through its effector peptide Ang-(1-7) and receptor Mas1 induces vasodilation and attenuates Ang II-induced vasoconstriction. In endothelial cells activation of the ACE2/Ang-(1-7)/Mas1 axis increases production of the vasodilator’s nitric oxide and prostacyclin’s and in vascular smooth muscle cells it inhibits pro-contractile and pro-inflammatory signaling. Endothelial ACE2 is cleaved by proteases, shed into the circulation and measured as soluble ACE2. Plasma ACE2 activity is increased in cardiovascular disease and may have prognostic significance in disease severity. In addition to its enzymatic function, ACE2 is the receptor for severe acute respiratory syndrome (SARS)-coronavirus (CoV) and SARS-Cov-2, which cause SARS and coronavirus disease-19 (COVID-19) respectively. ACE-2 is thus a double-edged sword: it promotes cardiovascular health while also facilitating the devastations caused by coronaviruses. COVID-19 is associated with cardiovascular disease as a risk factor and as a complication. Mechanisms linking COVID-19 and cardiovascular disease are unclear, but vascular ACE2 may be important. This review focuses on the vascular biology and (patho)physiology of ACE2 in cardiovascular health and disease and briefly discusses the role of vascular ACE2 as a potential mediator of vascular injury in COVID-19.
Computing the feasible operating region of active distribution networks: Comparison and validation of random sampling and optimal power flow based methods
Authors: Contreras Daniel A. , Rudion Krzysztof 
Published: January 2021

AbstractThe feasible operating region (FOR) indicates the operation points that an active distribution network can achieve at the interconnection point with the transmission grid when operating flexible assets within it; without disturbing the stability of the grid itself. Even though the concept is not new, many novel methods to compute the FOR efficiently have been proposed in recent years, resulting in two main schools of thought: random sampling (RS) and optimal power flow (OPF) methods. Both approaches have their merits, yet no wide‐ranging analysis regarding scenarios in which each method could be best applied has been done so far. This paper focuses on performing such a comparison; however, capability charts of flexibility providing units and grids are usually modelled as irregular convex polygons, requiring some adaptation of the RS‐methods to allow for a proper comparison of the resulting feasible operating region. Correspondingly, new methods to adapt the extraction of random samples from generic capability charts are proposed in the paper. Using models of two radial distribution grids, both OPF‐ and RS‐based methods are compared and validated. Results show that RS methods are adequate for assessing small grids, especially with the proposed improvements, while OPF‐based methods excel in larger grids.
Single‐ and triple‐band bandpass filters using novel perturbed isosceles right‐angled triangular SIW cavities
Authors: Zhang Junjie , Liu Qing , Zhou Dongfang , Zhang Dewei 
Published: January 2021

AbstractHerein, a rigorous derivation of an isosceles right‐angled triangular (IRT) metallic cavity is analysed. Then, the transverse field components in the IRT substrate‐integrated waveguide (SIW) cavity are derived, and the expression of the resonant frequencies can also be obtained. Then, a novel perturbed IRT SIW cavity is proposed, which is based on the characteristics of resonant modes in IRT SIW cavity and the capacitive‐loading technique. Three prototypes were designed to verify the validity of the derivation and analysis in this study. First, a dual‐mode single passband filter was implemented using the perturbed modes TE102 and TE202. Next, two tri‐mode triple‐band bandpass filters (BPFs) using the perturbed modes TE101, TE102 and TE202 are proposed, synthesised, verified and measured for demonstration, including a second‐order direct‐coupled one which operates at 8.02, 11.44 and 12.52 GHz, and a fourth‐order direct‐coupled one which operates at 7.7, 11.0 and 12.1 GHZ. The measured curves agree well with the simulated ones. Very compact circuit sizes and excellent filtering performances have been achieved for the three prototypes.
Multi‐mode dual‐polarised cavity backed patch antenna array for 5G mobile devices
Authors: Di Paola Carla , Zhao Kun , Pedersen Gert F. , Zhang Shuai 
Published: January 2021

AbstractThis paper proposes a dual‐polarised cavity backed patch antenna for next generation phased arrays for mobile handsets. The antenna exhibits multi‐band performance, allowing to cover the 5G bands n257 (26.5–29.5 GHz), n258 (24.25–27.5 GHz), n261 (27.5–28.35 GHz) and a portion of band n260 (37–40 GHz). Two orthogonal modes are excited in the substrate integrated waveguide (SIW) cavity and show similar impedance matching and symmetric radiation patterns. A parasitic element is introduced on top of the cavity and shifted off‐centre to improve the port‐to‐port isolation and guide the main beam. A parametric study of the antenna dimensions is conducted to verify the multi‐resonance operating mechanism. The design is validated by the measurements of the fabricated four‐element array. The array scanning angle is from −35° to 38° for V‐pol and from −29° to 31° for H‐pol at 28 GHz, where the realised gain raises from 8 to 12 dBi.
The Tully-Fisher relation in dense groups at z ∼ 0.7 in the MAGIC survey
Authors: Abril-Melgarejo Valentina , Epinat Benoît , Mercier Wilfried , Contini Thierry , Boogaard Leindert A. , Brinchmann Jarle , Finley Hayley , Michel-Dansac Léo , Ventou Emmy , Amram Philippe , Krajnović Davor , Mahler Guillaume , Pineda Juan C. B. , Richard Johan 
Published: January 2021

Context. Galaxies in dense environments are subject to interactions and mechanisms that directly affect their evolution by lowering their gas fractions and consequently reducing their star-forming capacity earlier than their isolated counterparts.
Aims. The aim of our project is to get new insights into the role of environment in the stellar and baryonic content of galaxies using a kinematic approach, through the study of the Tully-Fisher relation (TFR).
Methods. We study a sample of galaxies in eight groups, over-dense by a factor larger than 25 with respect to the average projected density, spanning a redshift range of 0.5 < z < 0.8 and located in ten pointings of the MAGIC MUSE Guaranteed Time Observations program. We perform a morpho-kinematics analysis of this sample and set up a selection based on galaxy size, [O II]λλ3727,3729 emission line doublet signal-to-noise ratio, bulge-to-disk ratio, and nuclear activity to construct a robust kinematic sample of 67 star-forming galaxies.
Results. We show that this selection considerably reduces the number of outliers in the TFR, which are predominantly dispersion-dominated galaxies. Similar to other studies, we find that including the velocity dispersion in the velocity budget mainly affects galaxies with low rotation velocities, reduces the scatter in the relation, increases its slope, and decreases its zero-point. Including gas masses is more significant for low-mass galaxies due to a larger gas fraction, and thus decreases the slope and increases the zero-point of the relation. Our results suggest a significant offset of the TFR zero-point between galaxies in low- and high-density environments, regardless of the kinematics estimator used. This can be interpreted as a decrease in either stellar mass by ∼0.05 − 0.3 dex or an increase in rotation velocity by ∼0.02 − 0.06 dex for galaxies in groups, depending on the samples used for comparison. We also studied the stellar and baryon mass fractions within stellar disks and found they both increase with stellar mass, the trend being more pronounced for the stellar component alone. These fractions do not exceed 50%. We show that this evolution of the TFR is consistent either with a decrease in star formation or with a contraction of the mass distribution due to the environment. These two effects probably act together, with their relative contribution depending on the mass regime.
Establishing a reliable determination of the final mass for rapidly accreting supermassive stars
Authors: Haemmerlé L. 
Published: January 2021

Context. The formation of supermassive black holes possibly takes place via direct collapse, with a supermassive star (SMS) as its progenitor. In this scenario, the SMS accretes at > 0.1 M⊙ yr−1 until it collapses into a massive black hole seed as a result of the general-relativistic (GR) instability. However, the exact mass at which the collapse occurs is not known, as existing numerical simulations give us a divergent range of results.
Aims. Here, we address this problem analytically, which allows for reliable ab initio determination of the onset point of the GR instability, for given hydrostatic structures.
Methods. We applied the relativistic equation of radial pulsations in its general form to the hydrostatic GENEC models already published in the literature.
Results. We show that the mass of spherical SMSs forming in atomically cooled halos cannot exceed 500 000 M⊙, which stands in contrast to previous claims. On the other hand, masses in excess of this limit, possibly up to ∼106 M⊙, could be reached in alternative versions of direct collapse.
Conclusions. Our method can be used to test the consistency of GR hydrodynamical stellar evolution codes.
S3-Leitlinie zur kardiologischen Rehabilitation im deutschsprachigen Raum Europas
Authors: Schwaab Bernhard , Rauch Bernhard 
Published: January 2021

Was ist neu?
Indikationen zur kardiologischen Rehabilitation Zur Indikation und Durchführung der kardiologischen Rehabilitation (KardReha) ist erstmals eine evidenzbasierte Leitlinie auf S3-Niveau publiziert worden 1. Neben der federführenden DGPR wurde diese Leitlinie von 6 weiteren deutschen Fachgesellschaften (DGK, DGTHG, DGSP, DKPM, DGRW, BNK) sowie erstmals auch von den kardiologischen Gesellschaften aus Österreich (ÖKG) und der Schweiz (CPRS) konsentiert. Aufgrund der Bedeutung der beruflichen Wiedereingliederung für Patienten mit kardiovaskulären Erkrankungen war zudem die Deutsche Rentenversicherung (DRV) an der Erstellung der Leitlinie beteiligt. Über die Deutsche Herzstiftung wurden ebenfalls erstmals Patientenvertreter im Sinne einer partizipativen Entscheidungsfindung eingebunden. Neben Patienten mit koronarer Herzkrankheit (KHK) und Patienten mit systolischer Herzinsuffizienz (HFrEF) wurden weitere, auch seltenere Reha-Indikationen evaluiert. Hierzu zählen Patienten nach Herztransplantation oder mit Herzunterstützungssystem (VAD), nach Aortendissektion, nach Myokarditis sowie Patienten mit peripherer arterieller Verschlusskrankheit (paVK) und Erwachsene mit angeborenen Herzfehlern (EMAH).
Durchführung der kardiologischen Rehabilitation Für alle Indikationen wird die Evidenz zur Wirksamkeit der multidisziplinären Therapie in der KardReha (medizinische Betreuung, körperliches Training, Lebensstiländerungen, psychosoziale Interventionen und Schulungen) dargestellt. Zudem evaluiert die Leitlinie die etablierten Nachsorgeprogramme nach Durchführung einer KardReha (z. B. ambulante Herzgruppen, IRENA) 1.
Hyponatriämie – Ursachen, Diagnostik und Therapie
Authors: Kettritz Ralph 
Published: January 2021

Was ist neu?
Hyponatriämie und klinische Symptome Neuere Untersuchungen veranschaulichen das breite Spektrum der klinischen Hyponatriämie-assoziierten Symptome und weisen auf erhebliche kognitive Einschränkungen bei bereits milder Hyponatriämie hin.
Hyponatriämie und ihre Ursachen Eine genomweite Assoziationsstudie (GWAS) identifizierte bei Patienten mit Thiazid-induzierter Hyponatriämie ADH-unabhängige „loss-of-function“-Mutationen, die zu einer verminderten Aktivität des Prostaglandin-Transporters im Sammelrohr der Nieren führen. Diese genetische Prädisposition verstärkt die Aquaporin-2-Expression und begünstigt die Wasserrückresorption. Auch andere Medikamente wie Fluconazol können ADH-unabhängige Wirkungen auf AQP2 und die Wasserrückresorption entfalten.
Akute vs. chronische Hyponatriämie und Korrekturgeschwindigkeit Etwa 25–50 % der Hyponatriämie-Patienten erfahren eine Überkorrektur mit zu schnellem Anstieg des Serum-Na+. Die Bestimmung von Urin-Osmolarität und freier Wasser-Clearance kann helfen Überkorrekturen zu vermeiden.
Aktuelle Studien Neben etablierten SIADH-Therapien wie Flüssigkeitsrestriktion, hyperosmolaren Salzinfusionen und Harnstoffgabe wird gegenwärtig der Wert von SGLT2-Inhibitoren zur Behandlung von Patienten mit Hyponatriämie untersucht.
Antifibrotische Therapie – neue Indikationen bei Non-IPF-interstitiellen Lungenerkrankungen
Authors: Markart Philipp , Drakopanagiotakis Fotios , Wygrecka Malgorzata 
Published: January 2021

Was ist neu?
Nintedanib zur Behandlung der SSc-ILE Nintedanib reduziert den jährlichen Abfall der forcierten Vitalkapazität (FVC) bei Patienten mit interstitieller Lungenerkrankung (ILE) in Assoziation mit einer systemischen Sklerose (SSc) und ist in dieser Indikation neu zugelassen.
Nintedanib zur Behandlung der chronischen progredient fibrosierenden ILE In der INBUILD-Studie wurde Nintedanib bei Patienten mit chronischer progredient fibrosierender ILE (Non-IPF) untersucht. Eingeschlossen waren Patienten mit exogen allergischer Alveolitis (EAA), idiopathischer nichtspezifischer interstitieller Pneumonie (iNSIP), unklassifizierbarer idiopathischer interstitieller Pneumonie, ILE bei rheumatoider Arthritis, SSc-ILE, expositionsassoziierter ILE, ILE bei Mischkollagenose, Sarkoidose und anderen fibrosierenden ILE. Nintedanib führte auch in dieser Patientengruppe zu einer signifikanten Reduktion des jährlichen FVC-Abfalls. Zusätzlich zur Therapie der IPF und der SSc-ILE ist Nintedanib jetzt auch zur Behandlung anderer chronischer progredient fibrosierender ILE zugelassen.
Pirfenidon bei Non-IPF-ILE Pirfenidon wurde ebenfalls bei Patienten mit progredienter Non-IPF-Lungenfibrose untersucht. In der finalen Analyse der RELIEF-Studie konnte ein signifikant positiver Effekt auf den Verlauf der FVC durch die Pirfenidon-Behandlung nachgewiesen werden. Eine Zulassung in dieser Indikation liegt bisher nicht vor. Im Rahmen einer Phase-II-Studie wurde Pirfenidon bei unklassifizierbarer progredienter ILE untersucht. Die Lungenfunktionsmessung im Zentrum (sekundärer Endpunkt) ergab eine signifikante Abschwächung des FVC-Verlusts nach 24 Wochen in der mit Pirfenidon behandelten Gruppe versus Placebo. Eine Zulassung in dieser Indikation liegt bisher ebenfalls nicht vor.
Testosteronmangel im Alter – was ist zu tun?
Authors: Jaschke Nikolai Pirmin , Rachner Tilman D. , Hofbauer Lorenz C. 
Published: January 2021

Definition Der Testosteronmangel des alternden Mannes ist nach wie vor nicht präzise definiert. Verschiedene Fachgesellschaften fordern zwar unisono das Vorliegen spezifischer klinischer Symptome in Verbindung mit konsistent erniedrigten morgendlichen Testosteronspiegeln. Allerdings existieren für letztere keine einheitlichen Grenzwerte. Erschwerend kommt hinzu, dass einzelne Symptome des Testosteronmangels bei unterschiedlichen Testosteron-Schwellenwerten auftreten können.
Testosteronersatztherapie – Anti-Aging oder falsche Hoffnung? Während zahlreiche retrospektive und kleinere prospektive Studien mit suboptimalem Design den Nutzen einer Testosteronersatztherapie im Alter nahelegen, existieren nur wenige Placebo-kontrollierte, randomisierte, doppelt verblindete Untersuchungen, die klinisch relevante Endpunkte verlässlich untersucht haben. Zu diesen zählen: