bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular mechanisms of eukaryotic origin initiation, replication fork progression, and chromatin maintenance
Authors: Yuan Zuanning , Li Huilin
Published: September 2020

Eukaryotic DNA replication is a highly dynamic and tightly regulated process. Replication involves several dozens of replication proteins, including the initiators ORC and Cdc6, replicative CMG helicase, DNA polymerase α-primase, leading-strand DNA polymerase ε, and lagging-strand DNA polymerase δ. These proteins work together in a spatially and temporally controlled manner to synthesize new DNA from the parental DNA templates. During DNA replication, epigenetic information imprinted on DNA and histone proteins is also copied to the daughter DNA to maintain the chromatin status. DNA methyltransferase 1 is primarily responsible for copying the parental DNA methylation pattern into the nascent DNA. Epigenetic information encoded in histones is transferred via a more complex and less well-understood process termed replication-couple nucleosome assembly. Here, we summarize the most recent structural and biochemical insights into DNA replication initiation, replication fork elongation, chromatin assembly and maintenance, and related regulatory mechanisms.
New method to analyse delay of DDS and MMS in substation communication
Authors: Fang Shuhua , Li Zhongjie , Huang Lei
Published: September 2020

As the standard specification for substation, IEC61850 utilises the abstract communication service interface to map to the manufacturing message specification (MMS) to communicate between the substation level and the bay level. The conventional MMS adopts the client/server model, which results in a relatively large transmission delay. In order to solve this problem, the data distribution service (DDS) is used to replace MMS for its excellent reliability and timeliness. However, the communication law and mechanism of DDS have not been known which result in the insufficient application of DDS. An end‐to‐end (ETE) delay method is proposed to divide the communication process into different parts according to the sequence in time and analyse the ETE delay of each part. By this method, the delay law and difference of DDS and MMS are analysed and summarised. The simulation results by the optimised network engineering tool software validate that DDS has a smaller delay than MMS. Therefore, DDS can better meet the timeliness of intelligent substation.
Statistics of cascaded Rayleigh fading channels with arbitrary correlation
Authors: Ghareeb Ibrahim , Darwish Jamal
Published: September 2020

Exact expressions for the probability density function (PDF) and cumulative distribution function (CDF) of cascaded Rayleigh fading channels with arbitrary correlation but not necessarily identically distributed are derived. Furthermore, the PDF and CDF of the instantaneous signal‐to‐noise ratio are obtained. The cascaded channels are assumed to have slow frequency non‐selective arbitrarily correlated Rayleigh fading with arbitrarily values of fading parameters. Indeed, the expressions of the outage probability and average normalised channel capacity for this channel model are derived. The average bit error probability for coherently detected binary signals in additive white Gaussian noise channel as well as in arbitrarily correlated cascaded Rayleigh fading channels is obtained. Numerical results are also provided and authenticated by Monte Carlo simulation. To the best of the authors' knowledge, the derived expressions for this channel model are new and have not been reported in the literature.
LED lighting systems for smart buildings: a review
Authors: Chinchero Héctor F. , Alonso J. Marcos , Ortiz T Hugo
Published: September 2020

This study presents a review of smart light‐emitting diode (LED) lighting systems applied to smart buildings. The study is focused on drivers, protocols, technologies, communication networks and applications. An extended overview of the methodologies used for LED lighting control in smart buildings is addressed. The study also presents an integrated architecture able to achieve the necessary services and control methodologies for intelligent building energy management system for LED lightings systems in smart buildings.
Localisation of wireless nodes with partial connectivity in wireless sensor systems
Authors: Waqas Khan Muhammad , Khan Maryam , Hafeez Abdul
Published: September 2020

Owing to their short communication range, wireless nodes in wireless sensor networks (WSNs) can exchange information with devices in their vicinity only. Thus, in sparse networks, the full connectivity of the network is rarely achieved. This renders a centralised approach towards localisation in WSNs useless. Moreover, the exploitation of a centralised algorithm for localisation compromises the scalability in dense networks. Thus, a decentralised, location‐aware network with partial connectivity and hybrid (range and direction) measurements obtained between known sensors (reference sensors) and sensors at unknown locations (target sensors) is under focus. The decentralised location estimation is obtained using a linear least squares (LLS) approach and performance enhancements are achieved by introducing a weighing strategy to produce weighted least squares (WLS) estimates. This distributed estimation is made possible by designing a map stitching technique that forms the global map of the network from individual local maps of the wireless nodes without compromising the distributed nature of the network. In the analytical section of the study, theoretical mean squares error expression is derived for LLS estimation, and a Cramer–Rao lower bound is derived to bind the performance of the WLS solution. The algorithm's performance validation is conducted both theoretically and via simulations.
The Gaia-ESO survey: 3D NLTE abundances in the open cluster NGC 2420 suggest atomic diffusion and turbulent mixing are at the origin of chemical abundance variations
Authors: Semenova Ekaterina , Bergemann Maria , Deal Morgan , Serenelli Aldo , Hansen Camilla Juul , Gallagher Andrew J. , Bayo Amelia , Bensby Thomas , Bragaglia Angela , Carraro Giovanni , Morbidelli Lorenzo , Pancino Elena , Smiljanic Rodolfo
Published: September 2020

Context. Atomic diffusion and mixing processes in stellar interiors influence the structure and the surface composition of stars. Some of these processes cannot yet be modelled from the first principles, and they require calibrations. This limits their applicability in stellar models used for studies of stellar populations and Galactic evolution.

Aims. Our main goal is to put constraints on the stellar structure and evolution models using new refined measurements of the chemical composition in stars of a Galactic open cluster.

Methods. We used medium-resolution, 19 200 ≤ R ≤ 21 500, optical spectra of stars in the open cluster NGC 2420 obtained within the Gaia-ESO survey. The sample covers all evolutionary stages from the main sequence to the red giant branch. Stellar parameters were derived using a combined Bayesian analysis of spectra, 2MASS photometry, and astrometric data from Gaia DR2. The abundances of Mg, Ca, Fe, and Li were determined from non-local thermodynamic equilibrium (NLTE) synthetic spectra, which were computed using one-dimensional (1D) and averaged three-dimensional (3D) model atmospheres. We compare our results with a grid of Code d’Evolution Stellaire Adaptatif et Modulaire (CESTAM) stellar evolution models, which include atomic diffusion, turbulent, and rotational mixing.

Results. We find prominent evolutionary trends in the abundances of Fe, Ca, Mg, and Li with the mass of the stars in the cluster. Furthermore, Fe, Mg, and Ca show a depletion at the cluster turn-off, but the abundances gradually increase and flatten near the base of the red giant branch. The abundance trend for Li displays a signature of rotational mixing on the main sequence and abrupt depletion on the sub-giant branch, which is caused by advection of Li-poor material to the surface. The analysis of abundances combined with the CESTAM model predictions allows us to place limits on the parameter space of the models and to constrain the zone in the stellar interior, where turbulent mixing takes place.
The Changes of Theoretical Wave Power from Offshore to Coast in the South-western Black Sea
Authors: Gul Majidi Ajab , Bingölbali Bilal , Akpınar Adem
Published: September 2020

This study concentrates on the changes of theoretical wave power from offshore to coastal regions of south-western Black Sea. The investigation also offers a long-term (31-year) wave power quantification analysis between 1979 and 2009 using the SWAN version 41.01AB numerical wave model. The wave resource assessment is performed in terms of its seasonal and monthly variability of wave power, annual wave power directional distributions and the comparison of the maximum and median values of some important wave power parameters in the west of Istanbul a major city in Turkey that straddles Europe and Asia across the Bosphorus Strait. For this analysis, 10 point locations distributed on two perpendicular lines (KA and KE) to the coastline with five different depths (5, 25, 50, 75, and 100 m) in the areas of interest were selected. The data needed was extracted from the dataset produced by [1, 2] using a calibrated nested layered wave hindcast model SWAN forced with CFSR winds. The results show that the wave energy resource in the study area is high, and the potential locations can be considered for extracting wave electrical power.
Assessment of Rail Vibration Transmission from the Ground to the Foundation of a Building
Authors: Moskovets Mariya , Kanev Nikolay
Published: September 2020

This paper presents the problem of rail transport vibration transmission from the ground to building foundations. Field measurement results of vibration parameters on the ground near buildings and their foundations have been covered in this study. It has been shown that vibrations at the foundation of a building are much smaller than vibrations on the ground. The most intense vibrations on the foundation slab occur in the vertical direction. Comparison with other experimental data on vibration transfer from the ground to buildings structures has been made. The data obtained can be utilized in designing vibration protection measures and to analytically predict vibration effects in buildings. This analysis can be performed after measuring the vibration of rail transport on the ground surface.
Decay of Non-Diffuse Sound Fields in a Room
Authors: Novoselova Alena , Kanev Nikolay
Published: September 2020

The paper presents the results of a study of a non-diffuse sound field decay in a room. In a laboratory experiment, a model of a room in the form of a rectangular parallelepiped with a size of 0.7 x 0.4 x 0.4 m is used. Two non-parallel walls are coated with sound absorbing material. Sound scattering elements can be placed on the third wall which is perpendicular to the absorbing ones, which allows to change the field diffusion degree. The sound field in such a room has a strong anisotropy, its energy decays according to the exponential-power law. Sound decay curves were measured at various positions of the sound source and microphone at frequencies of 4 kHz. The decay curves are compared, their dependence on the relative position of the sound source and microphone is analyzed.
Development of typical elements of silencers for internal combustion transport engines
Authors: Kunina Anna , Tupov Vladimir
Published: September 2020

Analysis of various methods for calculating acoustic efficiency of the transport engine noise silencers was carried out, their advantages and disadvantages were considered. Besides, it was shown that acoustic calculation methods, in particular the four-terminal method, could be used at the relatively small noise silencer structure elements cross-section and provide the acceptable accuracy. Analytical dependence for calculating the noise silencer acoustic efficiency using coefficients of its transfer matrix are provided. Conducted analysis of the transport engine noise silencer design made it possible to develop a number of typical noise-suppressing elements, using which allows to synthesize most of the reactive noise silencers for this purpose. On the example of a specific exhaust noise silencer, a method is shown for its representation in the form of a set of cascade-connected developed typical noise suppressing elements, each of them is described by a corresponding transfer matrix. Multiplying these matrices, the given noise silencer transfer matrix coefficients could be obtained. The resulting mathematical model of a noise silencer makes it possible to calculate its acoustic efficiency depending on its frequency and opens up a possibility to further optimize the noise silencer design using a computer. Standard elements versatility indicates possibility of their widespread use in calculating and designing various types of vehicle reactive noise silencers.
Influence of the ground on the sound screen efficiency
Authors: Oganesyan Suzanna , Komkin Alexandr
Published: September 2020

Characteristic features of evaluating the acoustic efficiency of sound screen on the ground were considered. To simplify the analysis, noise source and control point were located symmetrically on both sides of the screen. Their position was determined by the angle α and by the effective screen height. Influence of the α on the efficiency of a semi-infinite screen, and then on a decrease in this efficiency in the presence of the ground was analyzed.
Passive Acoustic Method in Bubble Size Distribution Determination
Authors: Gavrilev Stepan , Ivanov Mikhail
Published: September 2020

The paper is considering existing methods for determining the gas phase hydrodynamic properties in liquid medium. This paper presents a passive hydroacoustic method for determining the air bubbles size distribution in water. Advantage of this method contrasting to the active ones lies in its invasiveness. Mathematical model proposed for converting the spectrum of noise emitted by a cloud of bubbles into size distribution was tested in a number of experiments. Experiments were carried out in a glass cubic reservoir filled with water. Experiment results were verified by comparison with the photometric method.
Zurück ins Leben finden
Authors: Bergner Franziska
Published: September 2020

Bei der der Akzeptanz- und Commitmenttherapie werden klassische verhaltenstherapeutische Techniken mit achtsamkeits- und akzeptanzbasierten Strategien kombiniert. Unsere Autorin erläutert, wie es Patienten dadurch gelingt, nicht mehr gegen ihre Erkrankung anzukämpfen, sondern sie zu akzeptieren, die Perspektive zu ändern und psychische Flexibilität zu erlangen.
Beliebigkeit und Verbindlichkeit der Teilnahme an
Balint-Gruppen
Authors: Herzog Philipp
Published: September 2020

Das Gelingen einer Balint-Gruppensitzung hängt neben der
Leiterqualifikation und der Motivation der Teilnehmer von weiteren Faktoren
ab, die nicht innerhalb sondern außerhalb der Gruppe zu suchen sind.
Als Subsystem im Gesamtsystem des Gesundheitswesens mit seinen
administrativen Parametern ist die Balint-Gruppenarbeit eingebettet eine
Matrix von Bedingungen, mit denen der Gruppenleiter umso leichter umgehen
kann, je besser er sie kennt und gegenüber den Gruppenteilnehmern
tansparent macht. Der Autor hat diese Faktoren analysiert und daraus ein
formalisiertes Konzept in Form eines „Aufnahmebogens für
Balint-Gruppenteilnehmer“ entwickelt, das hier zur Diskussion
gestellt wird.
IL-17 regulates expression of cytokines in human osteoblasts rather than bone-specific genes
Authors: Drynda Andreas , Drynda Susanne , Lohmann Christoph H. , Bertrand Jessica , Kekow Jörn
Published: September 2020

Objective The cytokine IL-17 plays a crucial role in the development and promoting of inflammatory rheumatic diseases, such as psoriasis arthritis and ankylosing spondylitis. The influence of IL-17 on the osteoblast differentiation from mesenchymal stem cells has already been well studied. However, the effect of IL-17 on mature osteoblasts is not yet fully understood.

Methods In this study, the influence of IL-17 on the expression of osteogenic markers and pro-inflammatory cytokines was analyzed on mRNA and protein level in an osteoblast cell culture model.

Results Our data indicate that IL-17 alone has no significant influence on the expression of osteoblast-specific genes. However, a significant upregulation of pro-inflammatory cytokines at the transcriptional level by IL-17 was observed in primary osteoblasts. This effect on the regulation of pro-inflammatory cytokines was abolished completely by administration of a therapeutic anti-IL-17 antibody. Co-stimulation with TNF-α and IL-17 led to an upregulation of pro-inflammatory cytokines, which significantly exceeded the additive effect of both cytokines. In this co-stimulation, the anti-IL-17 antibody could not completely reverse the IL-17 effect. The same IL-17 and TNF-α effect was observed in osteoblast-like cells (MG63), whereas IL-17 alone did not induce the expression of pro-inflammatory cytokines.

Conclusion The upregulation of the pro-inflammatory cytokines IL-1, IL-6, and IL-8 in primary osteoblasts by IL-17 indicates an indirect regulatory effect on osteoclastogenesis and activation of bone resorption. The therapeutic IL-17 antibody reduced the IL-17 induced release of pro-inflammatory cytokines by osteoblasts and this, in turn, could also reduce the effect on osteoclast differentiation and bone resorption. Our study underlines the important role of osteoblasts as major players in the osteoimmunologic network.
Ein seltener Fall eines renalen ektopen Schilddrüsengewebes
Authors: Kajaia David , Hager Benjamin , Kliebisch Stefan , Weingärtner Karl , Seitz Gerhard , von Streitberg Ulrich , Seggewiß-Bernhardt Ruth , Zugor Vahudin
Published: September 2020

Nach einer roboterassistierten rechtsseitigen Nephrektomie einer tumortragenden Niere wird ektopes Schilddrüsengewebe an der Niere nachgewiesen. Dies ist extrem selten in der Literatur beschrieben. Ektopes Schilddrüsengewebe ist selten und tritt meist im Halsbereich und im oberen Mediastinum auf. Die klinischen Symptome sind von Größe, Lokalisation und hormoneller Funktion des ektopen Gewebes abhängig. Therapie der Wahl bleibt die operative Entfernung des ektopen Gewebes, in vereinzelten Fällen bleibt auch eine konservative Therapie als Option. Dieser Artikel soll dazu dienen, bei renalen unklaren Raumforderungen differentialdiagnostisch auch an paraneoplastisches oder ektopes Gewebe aus anderen Organen zu denken.
Fetal Hemodynamic Response to Maternal Oxygenation in Normal and Complicated Pregnancies
Authors: deng Yan , jin Ying , Xu Ran , Zeng Shi
Published: September 2020

Maternal oxygenation (MO) is widely applied in obstetrics. Scholars have conducted numerous studies on maternal hyperoxygenation and have reported many theoretical and applied achievements and a number of different points of view. The main purpose of this article is to discuss the effect of maternal oxygenation on fetal circulation during normal and complicated pregnancies and to ascertain its potential side effects and research gaps in this field. In complicated pregnancies, the fetus may benefit from oxygen therapy. However, large randomized controlled trials and longitudinal studies are necessary to support the widespread application of maternal oxygenation in this context.
Effect of Whole-body Vibration Combined with Task Oriented Training on Muscle Strength, Balance, and Gait in Stroke Patients with Hemiplegia: A Pilot Randomized Controlled Trial
Authors: Choi Kwang-Yong , Kim Jung-Hee , Lee ByoungHee
Published: September 2020

The current study aimed to evaluate the effects of whole-body vibration combined with task-oriented training on muscle strength, balance, and gait in stroke patients with hemiplegia. In total, 24 stroke patients were included in this study. All participants were randomly assigned to either the whole-body vibration combined with task-oriented training group (n=12) or the whole-body vibration group (n=12). The WBVMT group underwent training (8 sets) for 30 min a day, 5 times per week for 4 weeks. Meanwhile, the WBV group underwent training (8 sets) for 30 min a day, 5 times per week for 4 weeks. Both groups received standard rehabilitation physical therapy for 60 min a day, 5 times a week for 4 weeks. In all participants, the scores for the hip extensor (HE) and knee extensor (KE) muscle strength, Five Times Sit-to-Stand (FTSTS) Test, limit of stability (LOS), Timed Up and Go (TUG) Test, Berg Balance Scale (BBS), 10-Meter Walk Test (10MWT), and 6-Min Walk Test (6MWT) were evaluated before and after the intervention. The WBVMT and WBV groups had a significant increase in the scores for HE and KE strength, FTSTS test, LOS, TUG test, BBS, 10MWT, and 6MWT (p<0.05). In particular, the WBVMT group had a significantly greater improvement than the WBV group in terms of KE muscle strength and TUG test, BBS, 10MWT, and 6MWT scores (p<0.05). WBVMT improved muscle strength, balance, and gait in stroke patients with hemiplegia.
Frequency Modulation System and Bone Conduction Hearing Aid: Electroacoustic Verification
Authors: Paccola Elaine Cristina Moreto , Costa Filho Orozimbo Alves , Jacob Regina Tangerino Souza
Published: September 2020

Introduction A protocol has not yet been developed to perform electroacoustic measurements and behavioral tests to fit the frequency modulation (FM) system in bone conduction hearing aid (BCHA) users. Electroacoustic verification, with “FM transparency” achieved, ensures user audibility of FM transmitter and hearing aid signals.

Objective To propose and validate a protocol for electroacoustic verification of the FM system coupled to the BCHA.

Method Twenty-four sets of FM system and BCHA were submitted to electroacoustic verification, using a receiver and a plastic adapter to connect the BCHA to a 2cc coupler in the hearing instrument analyzer. The measurements were performed in the acoustic box, at 65 dB sound pressure level (SPL), with International Speech Test Signal (ISTS), first to the BCHA microphone and then to the FM system microphone, to determine the transparency, in which equivalent inputs for both microphones result in equivalent outputs. The FM gain or volume has been adjusted to try to gain transparency for the outputs of the two input devices.

Results Transparency was achieved for all sets evaluated, but in some combinations, adjustments to the FM receiver gain over the manufacturer's default setting were required.

Conclusion The proposed protocol proved to be effective for the electroacoustic verification of the FM system coupled to the BCHA.
Radiographic and Biomechanical Assessment of Three Implant Designs for Canine Cementless Total Hip Replacement
Authors: Worden Natalie J. , Ash Kristian J. , Ordway Nathaniel R. , Miller Mark A. , Mann Kenneth A. , VanDeventer Gretchen M. , Valenzano Dominick M. , Hart Robert , Kayano Mitsunori , Hayashi Kei
Published: September 2020

Objective The aim of this study was to evaluate the relationship between radiographic fit/fill measurements and biomechanical performance of three canine cementless total hip implant designs using an in vitro biomechanical testing protocol that replicates compression and torsion.

Study Design Eighteen (six/group) canine cadaveric femurs were implanted with one of three cementless total hip implant designs: (1) collarless, (2) collared or (3) lateral bolt stems. Femoral length, canal flare index (CFI), canal fill, stem fit, stem level and stem angle were measured as independent variables. Biomechanical performance was tested using physiological, non-destructive gait loading (loading protocols) and destructive testing (failure protocols).

Results During loading protocols, compressive stiffness was influenced by stem level (p < 0.05) and torsional stiffness was influenced by stem level and CFI for collarless stems (p < 0.05). During failure protocols, peak load was influenced by mediolateral (ML) stem angle (p < 0.05) and CFI (p < 0.01) for collarless stems and CFI for lateral bolt stems (p < 0.05). Peak torque was influenced by ML stem angle, craniocaudal stem angle and CFI for collarless stems (p < 0.05) and average ML fill for collared stems (p < 0.05).

Conclusion Biomechanical performance of collarless stems in cementless hip arthroplasty is more impacted by radiographic fit/fill than lateral bolt and collared stems. As a result, collarless stems may be more dependent on preoperative fit and intraoperative precision.
Hyperfibrinolysis in Patients with Solid Malignant Neoplasms: A Systematic Review
Authors: Winther-Larsen Anne , Sandfeld-Paulsen Birgitte , Hvas Anne-Mette
Published: September 2020

Solid malignant neoplasms have the capability of disturbing the fibrinolytic system, leading to primary hyperfibrinolysis, a paraneoplastic syndrome that potentially results in severe bleeding. Yet, the full extent of primary hyperfibrinolysis in solid malignant neoplasms is unknown. Thus, the purpose of this study was to systematically review the current literature regarding clinical manifestations, biochemical diagnosis, and treatment of primary hyperfibrinolysis in patients with solid malignant neoplasms. The review was performed in agreement with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases PubMed, Embase, Scopus, and Web of Science were searched on December 5, 2019, without time limits. Studies were included if they comprised at least one biochemical marker of fibrinolysis in addition to fibrinogen degradation products such as D-dimer, and furthermore included a correlation between biochemical marker and clinical outcome. In total, 12 studies were included. All studies were case reports including a total of 21 patients. Prostate cancer was the most frequently represented cancer type (76%), and the majority of cancer patients had metastatic disease (81%). Spontaneous bleeding was the clinical presentation in the majority of patients (76%), and the most frequently localization for the bleedings was subcutaneous. Antifibrinolytic agents were the most commonly used treatment and ceased bleedings in 80% of patients. Three patients died of uncontrolled bleedings. In conclusion, primary hyperfibrinolysis induced by solid malignant neoplasms is a rare but potentially life-threatening condition that should be considered, especially in patients with metastatic disease presenting with serious, spontaneous subcutaneous bleedings. A standardized diagnostic strategy is strongly needed.
Arrowhead Injury of Central Nervous System: Three Rare Cases from Rural India
Authors: Harsh Viraat , Alda Hemant , Singh Shashwat , Kumar Jayendra , Sahay Chandra B. , Kumar Anil
Published: September 2020

A penetrating central nervous system (CNS) injury on account of an arrowhead is a rarity in the modern era. When managing such cases surgically, special care is taken to prevent injury to the neurovascular structures lying in the vicinity of the wound. Fired arrows are categorized as low-velocity missiles, but the size, shape and aerodynamic stability of the missile are also important factors in establishing the complexity of the wound. We present three such cases of penetrating injury of the CNS by fired arrows, two injuring the head and the third injuring the spinal cord. The arrowheads were successfully retrieved without any complications. Salient features to be taken care of while managing such patients have also been also discussed.
Gratification Disorder as an Early Marker of Rett Syndrome: Two Pediatric Case Reports
Authors: Singhapakdi Kanya , Maertens Paul
Published: September 2020

Gratification disorder (GD) is a form of stereotyped posturing with mechanical pressure applied to the genitalia without manual manipulation and is generally considered benign. Here, we describe two patients who exhibited GD. Both were later diagnosed with Rett syndrome via genetic sequencing. In both patients, GD preceded the onset of the hallmark hand stereotypies of Rett syndrome. We therefore conclude that GD is not as benign as previously assumed and in fact can be an early sign of Rett syndrome. Further studies are needed to evaluate the prevalence of GD in Rett girls with the MECP2 genotype.
Possible Protective Role of Melatonin in Pediatric Infectious Diseases and Neurodevelopmental Pathologies
Authors: Molina-Carballo Antonio , Jerez-Calero Antonio Emilio , Muñoz-Hoyos Antonio
Published: September 2020

Melatonin, produced in every cell that possesses mitochondria, acts as an endogenous free radical scavenger, and improves energetic metabolism and immune function, by complex molecular crosstalk with other intracellular compounds. There is greatly increasing evidence regarding beneficial effects of acute and chronic administration of high melatonin doses, in infectious, developmental, and degenerative pathologies, as an endothelial cell and every cell protectant.
Comparison of Ischemic Preconditioning and Systemic Piracetam for Prevention of Ischemia-Reperfusion Injury in Musculocutaneous Flaps
Authors: Demiröz Anıl , Derebaşınlıoğlu Handan , Ercan Alp , Arslan Hakan , Aydın Övgü , Ekmekçi Hakan , Balcı Ekmekçi Özlem , Aydın Yağmur
Published: September 2020

Background Ischemia-reperfusion injury plays an important role in flap failure. Ischemic preconditioning technique is the only proven method for preventing ischemia-reperfusion injury, but it is not used widely in daily practice because of difficulties such as prolonging the operation time, need for surgical experience, and increasing the risk of complications. This study has been performed with the assumption that piracetam may be a simple and inexpensive alternative to the preconditioning technique due to its antioxidant, antiaggregant, rheological, anti-inflammatory, antiapoptotic, cytoprotective, and immune modulating effects.

Methods Thirty-two rats were divided into four groups and latissimus dorsi musculocutaneous flaps were raised. No extra procedure was applied, and no treatment was given to the control group. Four hours of ischemia was created by clamping the thoracodorsal pedicle in the second group. The animals in the third group were treated with 10 minutes of ischemia and reperfusion periods as a preconditioning procedure before the 4 hours of ischemia. Animals in the fourth group received systemic piracetam 30 minutes before and 6 days after reperfusion. Nitric oxide and myeloperoxidase levels in serum and tissue, acute inflammatory cell response, and vascular proliferation in tissue were examined at the postoperative 24th hour and 10th day.

Results Myeloperoxidase activity in both preconditioning and piracetam groups, was significantly lower than the ischemia-reperfusion group. Acute inflammatory cell response was similarly decreased in both preconditioning and piracetam groups compared with ischemia-reperfusion group. Tissue measurements of nitric oxide were also significantly higher in both preconditioning and piracetam groups than in the ischemia-reperfusion group. However, vascular proliferation increased in the preconditioning group, while it did not show any significant change in the piracetam group.

Conclusion This study shows that systemic piracetam treatment provides protection against ischemia-reperfusion injury in musculocutaneous flaps and can offer a simple and inexpensive alternative to the preconditioning technique.
An Overview of Digital Health in the Transition of Pediatric to Adult Epilepsy Care
Authors: Bernard-Willis Ysabeau , Oliveira Emily De , Lakhan Shaheen E
Published: September 2020

Children with epilepsy often have impairments in cognitive and behavioral functioning which may hinder socio-occupational well-being as they reach adulthood. Adolescents with epilepsy have the added worry of health problems while starting the transition from family-centered pediatric care into largely autonomous adult care. If this transition is not appropriately planned and resourced, it may result in medical mistrust, nonadherence, and worsening biopsychosocial health as an adult. In recent years, there has been increased availability of digital health solutions that may be used during this stark change in care and treating teams. The digital health landscape includes a wide variety of technologies meant to address challenges faced by patients, caregivers, medical professionals, and health care systems. These technologies include mobile health products and wearable devices (e.g., seizure monitors and trackers, smartphone passive data collection), digital therapeutics (e.g., cognitive/behavioral health management; digital speech–language therapy), telehealth services (e.g., teleneurology visits), and health information technology (e.g., electronic medical records with patient portals). Such digital health solutions may empower patients in their journey toward optimal brain health during the vulnerable period of pediatric to adult care transition. Further research is needed to validate and measure their impact on clinical outcomes, health economics, and quality of life.
Effects of Ischemic Preconditioning and C1 Esterase Inhibitor Administration following Ischemia-Reperfusion Injury in a Rat Skin Flap Model
Authors: Masa Inmaculada , Casado-Sánchez César , Crespo-Lora Vicente , Ballestín Alberto
Published: September 2020

Background Ischemia-reperfusion (I/R) injury is a serious condition that can affect the success rate of microsurgical reconstructions of ischemic amputated limbs and complex tissue defects requiring free tissue transfers. The purpose of this study was to evaluate the effects of ischemic preconditioning (IPC) and C1 esterase inhibitor (C1-Inh) intravenous administration following I/R injury in a rat skin flap model.

Methods Superficial caudal epigastric skin flaps (3 cm × 7 cm) were performed on 50 Wistar rats that were randomly divided into five groups. Ischemia was not induced in the control group. All other flaps underwent 8 hours of ischemia prior to revascularization: I/R control group (8-hour ischemia), IPC group (preconditioning protocol + 8-hour ischemia), C1-Inh group (8-hour ischemia + C1-Inh), and IPC + C1-Inh group (preconditioning protocol + 8-hour ischemia + C1-Inh). Survival areas were macroscopically assessed after 1 week of surgery, and histopathological and biochemical evaluations were also measured.

Results There were no significant differences in flap survival between the treatment groups that were suffering 8 hours of ischemia and the control group. A significant increase in neovascularization and lower edema formation were observed in the IPC group compared with that in the I/R group. Biochemical parameters did not show any significant differences.

Conclusion Intravenous administration of C1-Inh did not significantly modulate I/R-related damage in this experimental model, but further research is needed. On the other hand, IPC reduces tissue damage and improves neovascularization, confirming its potential protective effects in skin flaps following I/R injury.
A linewidth locking method to control the microwave power in optically pumped cesium-beam clocks
Authors: Xie Weibin , Wang Qing , He Xuan , Xiong Zezheng , Chen Nan , Fang Shengwei , Qi Xianghui , Chen Xuzong
Published: September 2020

In this paper, we present a linewidth locking method to control the microwave power in optically pumped cesium-beam frequency standards. The responses of optically pumped cesium-beam tubes and classical cesium-beam tubes are analyzed and compared against the power of the microwave field. Due to the wide probability distribution of atomic velocity resulting from the optical state preparation and detection, the linewidth of the Ramsey pattern is sensitive to the microwave power. The results can be used to control the microwave power instead of using the traditional extremum method. The advantages of the new method are discussed, and we named this new method the linewidth locking method. When the microwave power is well controlled at a low level by the linewidth locking method, the frequency stability of cesium-beam clocks will be improved to a certain degree for the reduction of the Ramsey pattern linewidth. In experiment, using the linewidth locking method, the Allan deviation of our optically pumped cesium-beam frequency standard is 2.64×10−12/τ and continues until the averaging time exceeds 1 × 105 s, which is 17% better than that using the traditional extremum method.
Numerical simulation of the period of surface micro-protrusions generated on titanium and stainless steel targets by femtosecond laser irradiation
Authors: Singh A. K. , Sinha S.
Published: September 2020

This article reports our simulation results on a period of surface micro-protrusions, which are generated on titanium and stainless steel 304 target surfaces by femtosecond pulsed laser irradiation. The period of the generated micro-protrusions for varying laser fluence level has been estimated using an approach derived from the linear hydrodynamic Kuramoto Sivashinsky model. Some of the parameters, needed for calculating the period of surface micro-protrusions, have been estimated by numerically solving one-dimensional heat equations. Temperature evolution inside the target upon irradiation with a femtosecond laser pulse has been simulated using the two temperature model until the time electron and lattice subsystems attain thermal equilibrium. Thereafter, temperature evolution in the target has been simulated by defining a single temperature of the target at every position and time. We have validated our theoretical model by comparing simulated variation of period of surface micro-protrusions with incident laser fluence, ablation depth per pulse, and time required for thermalization between electrons and lattice subsystems with the reported experimental data for titanium target. Subsequently, the validated model has been used to simulate the period of surface micro-protrusions which are generated on the stainless steel 304 target via femtosecond laser irradiation.
Universal correlations between the fragility and interparticle repulsion of glass-forming liquids
Authors: Lunkenheimer Peter , Humann Felix , Loidl Alois , Samwer Konrad
Published: September 2020

A recently published analytical model describing and predicting elasticity, viscosity, and fragility of metallic melts is applied for the analysis of about 30 nonmetallic glassy systems, ranging from oxide network glasses to alcohols, low-molecular-weight liquids, polymers, plastic crystals, and even ionic glass formers. The model is based on the power-law exponent λ representing the steepness parameter of the repulsive part of the inter-atomic or inter-molecular potential and the thermal-expansion parameter αT determined by the attractive anharmonic part of the effective interaction. It allows fitting the typical super-Arrhenius temperature variation of the viscosity or dielectric relaxation time for various classes of glass-forming matter, over many decades. We discuss the relation of the model parameters found for all these different glass-forming systems to the fragility parameter m and detect a correlation of λ and m for the non-metallic glass formers, in accord with the model predictions. Within the framework of this model, the fragility of glass formers can be traced back to microscopic model parameters characterizing the intermolecular interactions.
Strong spin-lattice coupling in tetragonal-like BiFeO3 films with thermal expansion anomalies
Authors: Xu Zedong , Deng Bei , Hu Sixia , Chen Lang
Published: September 2020

The evidence for a spin-lattice coupling in a tetragonal-like BiFeO3 (BFO) film is derived from thermal expansion measurements. Taking the advantage of La doping, the Néel temperature (TN) of the BFO film can be further adjusted over a broad range of temperatures. The lattice parameters exhibit anomalies near the Néel temperatures. The Bi0.8La0.2FeO3 film has a spin order-to-disorder transition at the TN without a structural phase transition, suggesting that a spin-lattice coupling drives the thermal expansion anomalies. The spin-lattice coupling can be enhanced by the coexistence of phases in the thicker BFO films. The density functional theory calculations show a smaller lattice constant of the c axis in the spin-order state than that in the spin-disorder state for the same tetragonal-like phase, which supports that the thermal expansion anomalies are a consequence of the spin-lattice coupling. Our findings may have application prospects for functional materials with controllable thermal expansions.
Photothermal testing of composite materials: Virtual wave concept with prior information for parameter estimation and image reconstruction
Authors: Thummerer G. , Mayr G. , Burgholzer P.
Published: September 2020

In this paper, we propose a new parameter estimation and image reconstruction approach for the photothermal testing of composite materials. Therefore, the full multidimensional evaluation method, virtual wave concept, is extended to estimate the orthotropic thermal diffusivity tensor and to reconstruct the initial temperature distribution after a laser spot heating in an orthotropic material. We establish a formal relationship between the virtual speed of sound tensor and the thermal diffusivity tensor. Furthermore, we show how prior information in the form of positivity and sparsity can be incorporated in the regularization process to improve the solution of the inverse imaging problem. In a second step, the initial temperature distribution is reconstructed by applying ultrasonic imaging methods on the calculated 3D bimodal virtual wave field. This new approach is validated on simulation and experimental data of a unidirectional carbon fiber reinforced polymer. The information loss that results from entropy production during heat diffusion can be partly compensated by including prior information. This allows an accurate parameter estimation and a high-resolution image reconstruction.
Spontaneous polarization of thick solid ammonia films
Authors: Sagi Roey , Akerman Michelle , Ramakrishnan Sujith , Asscher Micha
Published: September 2020

Ammonia molecules have an important role in the radiation-induced chemistry that occurs on grains in the cold interstellar medium and leads to the formation of nitrogen containing molecules. Such grains and surfaces are primarily covered by water ices; however, these conditions allow the growth of solid ammonia films as well. Yet, solid ammonia know-how lags the vast volume of research that has been invested in the case of films of its “sibling” molecule water, which, in the porous amorphous phase, spontaneously form polar films and can cage coadsorbed molecules within their hydrogen-bonded matrix. Here, we report on the effect of growth temperature on the spontaneous polarization of solid ammonia films (leading to internal electric fields of ∼105 V/m) within the range of 30 K–85 K on top of a Ru(0001) substrate under ultra-high vacuum conditions. The effect of growth temperature on the films’ depolarization upon annealing was recorded as well. By demonstrating the ability of ammonia to cage coadsorbed molecules, as water does, we show that temperature-programmed contact potential difference measurements performed by a Kelvin probe and especially their temperature derivative can track film reorganization/reconstruction and crystallization at temperatures significantly lower than the film desorption.
Response to “Comment on ‘Sliding planar conjoined cut-wire-pairs: A novel approach for splitting and controlling the absorption spectra’” [J. Appl. Phys. 128, 126101 (2020)]
Authors: Karacan Nezihe , Ekmekci Evren , Turhan-Sayan Gonul
Published: September 2020

In the Comment by S. C. Bakshi and D. Mitra [J. Appl. Phys. 128, 126101 (2020)], it is claimed that “cross-polarization reflection was ignored in calculation of absorptivity of that structure,” “the actual absorptivity of the new peaks [is] extremely poor (around 40%),” and hence the vertical sliding mechanism of conjoined cut-wire-pairs (CCWPs) “can't be adopted for efficient switching/tuning of the absorption spectra.” In this Response, we will demonstrate that these claims are not only unfair but also incorrect as they result from an unfortunate fundamental mistake they made in the attempt of replicating the effective free-space absorber array topology implied in the original article [J. Appl. Phys. 124, 105103 (2018)]. The use of “CCWP unit-cell within a metallic waveguide” scenario in the original work implies the realization of an infinitely large periodic array of a “super-cell,” whose structure is determined by the well-known mirror image effect of the perfect electrical conductor type boundary condition imposed by the conducting walls of the waveguide. When this fact is ignored, but instead the free-space array is formed by simply repeating the same asymmetric CCWP unit-cell periodically, a completely different absorber array topology is obtained, which is clearly irrelevant to the original design. Therefore, the results reported in the Comment belong to an alternative absorber array; they do not represent the performance of the original design. In this Response, we will clarify our points outlined above to refute the claims made in the Comment to demonstrate the validity of the original results and the usefulness of the suggested absorber array for practical purposes.
Paramagnetism and martensite stabilization of tensile strained NiTi shape memory alloy
Authors: Kyianytsia A. , Gaudry E. , Ponçot M. , Boulet P. , Kierren B. , Hauet T.
Published: September 2020

We present an experimental and theoretical study of Pauli paramagnetism and martensite stabilization in a near equiatomic NiTi shape memory alloy. We demonstrate a direct correlation between strain-induced shear of the B19′ NiTi lattice and its electronic and thermodynamical features. An increase in the monoclinic angle β from 97.4 to 98° induces a 7% decrease in the magnetic susceptibility because of a shift and deepening of a dip in B19′ density of states at the Fermi level. It also produces a decrease in the B19′ enthalpy, which translates into an increase in the martensite-to-austenite transition temperature by 60 K.
Effective mass path integral simulations of quasiparticles in condensed phases
Authors: Remsing Richard C. , Bates Jefferson E.
Published: September 2020

The quantum many-body problem in condensed phases is often simplified using a quasiparticle description, such as effective mass theory for electron motion in a periodic solid. These approaches are often the basis for understanding many fundamental condensed phase processes, including the molecular mechanisms underlying solar energy harvesting and photocatalysis. Despite the importance of these effective particles, there is still a need for computational methods that can explore their behavior on chemically relevant length and time scales. This is especially true when the interactions between the particles and their environment are important. We introduce an approach for studying quasiparticles in condensed phases by combining effective mass theory with the path integral treatment of quantum particles. This framework incorporates the generally anisotropic electronic band structure of materials into path integral simulation schemes to enable modeling of quasiparticles in quantum confinement, for example. We demonstrate the utility of effective mass path integral simulations by modeling an exciton in solid potassium chloride and electron trapping by a sulfur vacancy in monolayer molybdenum disulfide.