bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pattern and Outcome of Cardiac Interventions Performed within and Outside Nigeria for Children with Structural Heart Diseases in Sokoto, North-western Nigeria
Authors: Sani U. M. , Waziri U. M. , Isezuo K. O. , Garba B. I. , Abubakar U. , Ismail S. 
Published: June 2020

Background: Management of structural heart diseases is quite challenging in Nigeria, due to limited availability and access to cardiac care services. There is paucity of data on the pattern and outcome of cardiac interventions in children from the study area.
Aims: To determine the pattern of cardiac interventions and the early outcome (within six-months) of such interventions in children with structural heart diseases (SHD) seen in our hospital.
Study Design: Descriptive cross-sectional study.
Place and Duration of Study: Department of Paediatrics, Usmanu Danfodiyo University Teaching Hospital (UDUTH), Sokoto, between August 2012 to September 2019.
Methodology: All children with SHDs seen at our hospital, but had Cardiac surgery or interventional cardiac procedures within and outside Nigeria were recruited. Relevant information including type of lesion, procedure performed and the outcome within the first six months and length of hospital stay was analyzed.
Results: Only 63 out of 780 (8.1%) children with structural heart diseases, aged 6 months-15 years (Mean age 6.5± 5.0 years, M: F = 1.3:1), had cardiac interventions. The interventions were surgical in 61 ((96.8%) and catheter-based in 2 (3.2%) patients; with 49 (77.8%) of these performed abroad. Patent Ductus arteriosus 14 (22.2%), Tetralogy of Fallot 14 (22.2%), ventricular septal defect 13 (20.6%) and atrial septal defect 6 (9.5%) were the commonest lesions for which interventions were undertaken. Early post-operative complications included pulmonary hypertensive crises, pericardial and pleural effusion, complete heart block and left branch pulmonary artery stenosis warranting re-intervention. During the first six months after the interventions, three (4.8%) patients died while 60 (95.2%) survivors were followed up. However, 25 (39.7%) of them were thereafter lost to follow.
Conclusion: Majority of the cardiac interventions were surgical, performed predominantly in older children with CHDs; and associated with good outcome. However, most of them were undertaken outside the country, highlighting the need to ensure these services are available and accessible locally.
Magnetic Structure and Metamagnetic Transitions in the van der Waals Antiferromagnet CrPS4
Authors: Peng Yuxuan , Ding Shilei , Cheng Man , Hu Qifeng , Yang Jie , Wang Fanggui , Xue Mingzhu , Liu Zhou , Lin Zhongchong , Avdeev Maxim , Hou Yanglong , Yang Wenyun , Zheng Yi , Yang Jinbo 
Published: June 2020

AbstractIn 2D magnets, interlayer exchange coupling is generally weak due to the van der Waals layered structure but it still plays a vital role in stabilizing the long‐range magnetic ordering and determining the magnetic properties. Using complementary neutron diffraction, magnetic, and torque measurements, the complete magnetic phase diagram of CrPS4 crystals is determined. CrPS4 shows an antiferromagnetic ground state (A‐type) formed by out‐of‐plane ferromagnetic monolayers with interlayer antiferromagnetic coupling along the c axis below TN = 38 K. Due to small magnetic anisotropy energy and weak interlayer coupling, the low‐field metamagnetic transitions in CrPS4, that is, a spin‐flop transition at ≈0.7 T and a spin‐flip transition from antiferromagnetic to ferromagnetic under a relatively low field of 8 T, can be realized for H∥c. Intriguingly, with an inherent in‐plane lattice anisotropy, spin‐flop‐induced moment realignment in CrPS4 for H∥c is parallel to the quasi‐1D chains of CrS6 octahedra. The peculiar metamagnetic transitions and in‐plane anisotropy make few‐layer CrPS4 flakes a fascinating platform for studying 2D magnetism and for exploring prototype device applications in spintronics and optoelectronics.
Printed Flexible Heaters‐Based Thermotherapy Platform for Multiduty Thermal Management
Authors: Liu Qun , Tian Bin , Luo Chengsheng , Liang Jing , Wu Wei 
Published: June 2020

AbstractPrinted flexible heaters (FHs) with excellent heating performance and thermal stability are quite desirable for the development of portable thermotherapy platform. Herein, the facile screen‐printing technology is used to fabricate the highly oxidation‐resistant Cu @ Ni rose‐stem nanowires (RSNWs) ‐ based low‐cost scalable FHs. The Cu @ Ni RSNWs possess low sheet resistance of 1.9 Ω sq−1 after low temperature sintering (90 °C). The FHs not only exhibit great oxidation resistance (almost no change at 180 °C for 30 min), but also maintain the great conductivity (ΔR/R0 < 0.3) even after being exposed to ambient atmosphere for 60 days. Furthermore, the FHs exhibit great heating performance with the saturation temperature of 172.8 °C under 6 V, and can keep stable heating cycles for 5500 s under both parameters of the stepwise‐rising voltage from 2 to 6 V and consistent load‐on voltage of 6 V. In addition, the heaters array can greatly shorten the time of raising the temperature of the blood bag from 5 to 20 °C. The outstanding heating performance of the FHs provides great chances for portable variable‐area flexible heating platform in the field of multiduty thermal management.
The Fast Charge Transfer Kinetics of the Lithium Metal Anode on the Garnet‐Type Solid Electrolyte Li6.25Al0.25La3Zr2O12
Authors: Krauskopf Thorben , Mogwitz Boris , Hartmann Hannah , Singh Dheeraj K. , Zeier Wolfgang G. , Janek Jürgen 
Published: June 2020

AbstractThe charge transfer kinetics between a lithium metal electrode and an inorganic solid electrolyte is of key interest to assess the rate capability of future lithium metal solid state batteries. In an in situ microelectrode study run in a scanning electron microscope, it is demonstrated that—contrary to the prevailing opinion—the intrinsic charge transfer resistance of the Li|Li6.25Al0.25La3Zr2O12 (LLZO) interface is in the order of 10−1 Ω cm2 and thus negligibly small. The corresponding high exchange current density in combination with the single ion transport mechanism (t+ ≈ 1) of the inorganic solid electrolyte enables extremely fast plating kinetics without the occurrence of transport limitations. Local plating rates in the range of several A cm−2 are demonstrated at defect free and chemically clean Li|LLZO interfaces. Practically achievable current densities are limited by lateral growth of lithium along the surface as well as electro‐chemo‐mechanical‐induced fracture of the solid electrolyte. In combination with the lithium vacancy diffusion limitation during electrodissolution, these morphological instabilities are identified as the key fundamental limitations of the lithium metal electrode for solid‐state batteries with inorganic solid electrolytes.
Synthesis of adipic acid through oxidation of K/A oil and its kinetic study in a microreactor system
Authors: Li Guangxiao , Liu Saier , Dou Xiaoyong , Wei Huilong , Shang Minjing , Luo Zheng‐Hong , Su Yuanhai 
Published: June 2020

AbstractSynthesis of adipic acid (AA) through the oxidation of cyclohexanol and cyclohexanone (K/A oil) with nitric acid was conducted in a capillary microreactor system. Effects of the temperature, the nitric acid concentration, the volumetric flow rate ratio of nitric acid to K/A oil, and the capillary length on the selectivity and the product yield were investigated systematically to achieve optimal reaction conditions. Notably, a high yield of AA (i.e., 90%) was achieved just in 6 seconds at 85°C with the use of 55 wt% nitric acid. Gas components produced in this oxidation process and its total volumetric flow rate were determined under various operational conditions, which was beneficial for reaction mechanism characterization and process optimization. Finally, a kinetic model was established, which was of crucial theoretical significance and practical value for optimizing the reactor design and better understanding such fast and highly exothermic multiphase processes with abundant gas production.
Metal–Graphene Hybrid Chiral Metamaterials for Tunable Circular Dichroism
Authors: Li Fuyu , Tang Tingting , Mao Yinghui , Luo Li , Li Jie , Xiao Jiaxin , Liu Kunlin , Shen Jian , Li Chaoyang , Yao Jianquan 
Published: June 2020

AbstractIn the field of optoelectronics, circular dichroism (CD) has caused great research interest because it is widely used in imaging and biosensing. A new method for dynamically controlling terahertz (THz) CD in metamaterials is proposed. By introducing chirality and graphene to metamaterials, a pair of chiral structures with completely opposite responses to left‐handed circularly polarized (LCP) waves and right‐handed circularly polarized (RCP) waves are designed. The influencing factors of CD are explored, including the gap of the structure, the linewidth of graphene, and the Fermi level of graphene. The largest CD (ΔR) is 77%. The CD can be actively modulated in a modulation range of 39–77% and the modulation depth is up to 38%. In addition, two‐channel and four‐channel chiral metasurfaces for near‐field imaging are designed in this way. Good imaging effects and on (“1”) or off (“0”) effects of the multichannel metasurface are demonstrated. This work provides new ideas for the design of tunable metasurfaces and promotes the application of metasurfaces in THz dynamic imaging.
Transient paraplegia due to subarachnoid haemorrhage following spinal anaesthesia
Authors: Olivei M. C. , Tamanti P. , Giachetti A. , Nespoli P. , Berta G. , Caironi P. 
Published: June 2020

SummarySpinal subarachnoid haemorrhage is a rare complication of spinal anaesthesia, especially following atraumatic lumbar puncture and in the absence of coagulopathies. The initial presentation of spinal subarachnoid haemorrhage is variable and paraplegia with full recovery within a few hours is rare. Bleeding can extend into the intracranial subarachnoid space, but there are only a few reports of symptomatic intracranial and spinal subarachnoid haemorrhage after spinal anaesthesia. We report co‐existing spinal subarachnoid haemorrhage and intracranial subarachnoid haemorrhage after atraumatic spinal anaesthesia in a 69‐year‐old woman without a coagulopathy. The day after surgery she developed flaccid paraplegia that spontaneously resolved in a few hours. Magnetic resonance imaging demonstrated subarachnoid high signal intensity from T11–S2, consistent with spinal subarachnoid haemorrhage. On the same day the patient complained of severe headache which was later followed by diplopia. Neurological imaging studies revealed diffuse distribution of blood in the subarachnoid space but no intracranial vascular malformations. At the time of diagnosis spontaneous recovery of spinal symptoms had already begun and the clinical manifestations eventually resolved with conservative management. The possibility of an intracranial haemorrhage should always be considered when spinal subarachnoid haemorrhage is identified, even in cases of uncomplicated spinal anaesthesia in patients with no known risk factors for spinal haemorrhage.
Anaesthetic management of emergency caesarean section with isolated cortical vein thrombosis and subacute intracerebral haemorrhage
Authors: Robson M. , Higgins N. , Evans E. 
Published: June 2020

SummaryWe report the case of an emergency caesarean section 5 days following the onset of a right‐sided hemiparesis due to an intracerebral haemorrhage. Computerised tomography imaging in the postoperative period revealed an isolated cortical vein thrombosis as the likely cause. The caesarean section was conducted under general anaesthesia following consideration of the risks and benefits and discussion of these with the patient. No peri‐operative complications occurred and neuro‐rehabilitation was commenced as an inpatient. This case highlights the importance of maintaining a targeted systolic blood pressure whilst avoiding increased intracranial pressure in the obstetric patient with an intracerebral haemorrhage, and that the mode and conduct of anaesthesia can have a profound impact on these measurements. To our knowledge, this is the first reported case of a patient having an emergency caesarean section after subacute intracerebral haemorrhage caused by an isolated cortical vein thrombosis and it demonstrates that general anaesthesia can be used safely in this context. In this complex obstetric case, the role of multidisciplinary team collaboration in the peri‐operative period was essential to optimising the patient’s outcome.
Electromagnetic interference shielding properties of graphene quantum‐dots reinforced poly(vinyl alcohol)/polypyrrole blend nanocomposites
Authors: Rani Priyanka , Ahamed Basheer , Deshmukh Kalim 
Published: June 2020

AbstractGraphene quantum dots (GQDs) reinforced poly(vinyl alcohol) (PVA)/polypyrrole (WPPy) nanocomposite films with various GQDs loadings were synthesized using the versatile solvent casting method. The structural and morphological properties of PVA/WPPy/GQDs nanocomposite films were investigated by employing Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. The thermogravimetric analysis revealed enhanced thermal stability of synthesized nanocomposites while enhanced dielectric properties were also observed. The maximum dielectric constant value for PVA/WPPy/GQDs nanocomposite films was observed to be ε = 6,311.85 (50 Hz, 150°C). The electromagnetic interference (EMI) shielding effectiveness (SE) of nanocomposite films was determined in the X‐band (8–12 GHz) and Ku‐band (12–18 GHz) frequency region. The EMI SE was found to be increased from 0.8 dB for the pure PVA film to 9.8 dB for the PVA/WPPy/GQDs nanocomposite film containing 10 wt% GQDs loading. The enhanced EMI shielding efficiency of nanocomposite films has resulted from the homogenous dispersion of GQDs in PVA/WPPy blend nanocomposites. Thus, the prepared nanocomposites are envisioned to utilize as a lightweight, flexible, and low‐cost material for EMI shielding applications.
Different Hierarchies of Anti–Modified Protein Autoantibody Reactivities in Rheumatoid Arthritis
Authors: Sahlström Peter , Hansson Monika , Steen Johanna , Amara Khaled , Titcombe Philip J. , Forsström Björn , Stålesen Ragnhild , Israelsson Lena , Piccoli Luca , Lundberg Karin , Klareskog Lars , Mueller Daniel L. , Catrina Anca I. , Skriner Karl , Malmström Vivianne , Grönwall Caroline 
Published: June 2020

ObjectiveAnti–citrullinated protein antibodies (ACPAs) are a hallmark of seropositive rheumatoid arthritis (RA). Yet, the precise disease‐relevant autoantigens that are targeted by ACPAs remains a matter of debate. This study utilized patient‐derived monoclonal ACPAs, rather than serum autoantibody analysis, to characterize the multireactivity to different protein modifications and to reveal autoantibody subsets in patients with RA.MethodsTwelve human monoclonal ACPAs (positive by the second‐generation cyclic citrullinated peptide test) were generated from 6 RA patients, and a head‐to‐head comparison of their reactivities was performed. For profiling, we used a complementary DNA–based protein array (Engine GmbH) and 3 peptide‐screening platforms with RA autoantigens (Thermo Fisher Scientific), citrullinated and carbamylated peptides (NimbleGen/Roche), or histone‐derived peptides with different posttranslational modifications (JPT Histone Code), covering >207,000 peptides (>7,800 gene products).ResultsThe fine‐specificity profiles of the investigated ACPAs varied, but all of the monoclonal ACPAs displayed multireactivity to a large number of citrullinated peptides/proteins, each characterized by specific binding properties. ACPA subsets could be defined by clone‐distinct consensus binding motifs (e.g., Cit–Gly, Gly–Cit, or Arg–Cit–Asp), with the most common ACPA recognition being that of a Gly in the +1 flanking position, but with additional amino acid preferences. For ACPA protein recognition, we observed a preference for citrullinated RNA‐binding proteins with high Arg/Gly content. Six of the 12 ACPA clones also bound acetylated lysine (KAc) or homocitrulline peptide motifs, displaying a similar affinity or higher apparent affinity than that for citrullinated peptides.ConclusionACPAs and anti–modified protein autoantibodies represent overlapping facets of RA autoimmunity and bind to a wide variety of modified proteins, extending well beyond the historically recognized set of RA autoantigens. So far, KAc reactivity has been detected only in the context of anti–carbamylated and anti–citrullinated peptide autoantibody responses, postulating the existence of hierarchies of autoreactivity in RA. Future investigations of ACPA fine specificities and functionality should take into consideration the presence of consensus Cit/Carb/KAc motifs and the multireactivity of these autoantibodies in patients with RA.
Einfluss moderner Medientechnik auf das Innenraumklima in Unterrichtsräumen am Beispiel des sommerlichen Wärmeschutzes
Authors: Wagner Stefan , Fülle Wolff , Dietz Eckhard 
Published: June 2020

AbstractDas Raumklima wird neben den solaren Wärmeeinträgen wesentlich durch die Wärmeabgabe von Personen, elektrischen Geräten usw. beeinflusst. Insbesondere durch die Verbesserung der thermischen Qualität der Gebäudehülle werden innere Lasten bei gutem Sonnenschutz der Verglasungen zunehmend raumklimabestimmend. Für die Gebäudeplanung stehen zur Beurteilung des sommerlichen Wärmeschutzes die Planungswerkzeuge und Anforderungsgrenzen aus diversen Regelwerken und Richtlinien zur Verfügung. Dieser Bericht zeigt die Grenzen dieser Regelwerke auf.
Experimentelle und numerische Untersuchung des Einflusses der Strahlungsasymmetrie auf die thermische Behaglichkeit am Beispiel temperierter Halbräume
Authors: Gritzki Ralf , Schinke Lars , Beyer Maximilian , Seifert Joachim , Felsmann Clemens 
Published: June 2020

AbstractDer Einfluss der Strahlungsasymmetrie auf die thermische Behaglichkeit wird in der Fachwelt in jüngster Zeit wieder kontrovers diskutiert. Die in den Vorschriften wie z. B. der DIN EN ISO 7730 [1] / DIN EN 16798‐1 [2] verankerten Grenzwerte lassen sich in ausgewählten Fällen deutlich überschreiten, ohne dass dies von den Nutzern als unbehaglich empfunden wird [3, 4]. In anderen Fällen hingegen ist die tatsächliche Nutzerakzeptanz deutlich geringer als vorhergesagt. Um die grundlegenden Zusammenhänge zwischen unterschiedlichen, dem Menschen aufgeprägten Werten der Strahlungsasymmetrie in Räumen und dem daraus resultierenden thermischen Empfinden der betroffenen Nutzer besser verstehen zu können, wurde von den Autoren eine Kombination von experimentellen Untersuchungen im Combined Energy Lab 2.0 der TU Dresden [5] in Verbindung mit Probandenversuchen und zusätzlichen numerischen Untersuchungen auf Basis dieser Probandenversuche gewählt. Die Versuchskonfigurationen und die Ergebnisse der Probandenversuche wurden hierbei als Basis für die gekoppelten Gebäude‐, Anlagen‐ und Strömungssimulationen genutzt. Somit ist es möglich, ein deutlich breiteres Spektrum an Versuchsanordnungen numerisch abzubilden und zudem die räumlich und zeitlich hoch aufgelöst verfügbaren Feldgrößen der Geschwindigkeiten, der Luft‐ und Strahlungstemperaturen sowie aller dazugehörigen Kriterien der thermischen Behaglichkeit in die Betrachtungen einzubeziehen.
Thermografie zur Erfassung von Schäden an Brückenbauwerken
Authors: Mold Lisa , Auer Mathias , Strauss Alfred , Hoffmann Markus , Täubling Benjamin 
Published: June 2020

AbstractBetonbauwerke wie Brücken sind ein wesentlicher Bestandteil des Straßennetzes. Um die Sicherheit und Gebrauchstauglichkeit einer Brücke zu gewährleisten, sind regelmäßige, z. T. aufwendige Inspektionen und Untersuchungen erforderlich, um Schäden an einem Bauwerk frühzeitig zu erkennen. Mit innovativen zerstörungsfreien Untersuchungsmethoden ist es möglich, den Schadenserkennungsprozess von Bauwerken zeitlich und kostenmäßig zu optimieren.In der Vergangenheit wurden bereits Drohnen für Oberflächenaufnahmen von Brücken mit Laserscan oder digitaler Bildgebung eingesetzt, um Schäden wie Risse und Abplatzungen zu erkennen. Diese Methoden sind zeitsparender als die herkömmlichen, komplexeren Verfahren zur Sichtprüfung. Um auch Schäden unter der Oberfläche mittels Flächenaufnahmen nachweisen zu können, wurde ein vielversprechender Ansatz – die Thermografie – untersucht. Ein großer Vorteil der Thermografie ist die flexible Einsatzmöglichkeit und zerstörungsfreie Anwendung am Bauwerk. Die Methode ermöglicht eine thermografische Aufzeichnung der gesamten Brücke. Durch Temperaturunterschiede auf der Oberfläche können Schäden wie Delamination, Hohlräume und Feuchtigkeitsstellen im Beton erkannt werden. Um die Zuverlässigkeit dieser Methode zur Erkennung der genannten Schäden gewährleisten zu können, wurden die Erkennungsgenauigkeiten und ‐grenzen ermittelt. Zu diesem Zweck wurden Tests an Betonproben durchgeführt, die Delamination, Hohlräume und feuchte Bereiche in unterschiedlichen Größen und Tiefen im Beton aufwiesen. Während der Tests wurden die Betonproben aktiv erhitzt. Im Laufe des Abkühlvorgangs erfolgte die Aufnahme der Oberfläche mit der Wärmekamera. Die Erstellung von nichtlinearen Finite‐Elemente‐Modellen der Testkörper ermöglichte weitere Variationen der Geometrien und der Temperaturen der Betonproben. Mittels der erhaltenen Daten konnte die Detektionswahrscheinlichkeit der untersuchten Schäden ermittelt und eine Empfehlung für die Anwendung dieser Methode gegeben werden.
Analyse der zulässigen Brandausbreitung über die Fassade
Authors: Engel Thomas , Werther Norman 
Published: June 2020

AbstractAufbauend auf den grundlegenden Forderungen der Bauordnung lassen sich aktuell in Deutschland verschiedene Erläuterungen zur Konkretisierungen des Schutzziels „Begrenzung der Brandausbreitung über die Fassade“ finden. Eine allgemeingültige Festlegung gibt es bisher nicht. Diese Festlegung wäre jedoch, insbesondere für die Betrachtung von neuen Fassaden und Außenwandbekleidungen, eine wichtige Basis. Die nachfolgende Studie beschreibt die aktuell in Deutschland zur Verfügung stehenden Grundlagen zur Bewertung „brandschutztechnisch sicherer“ Fassaden. Diese sind Prüfverfahren für Fassadenbrandversuche, Hintergründe für die Prüfverfahren, Vorgaben aus bauordnungsrechtlichen Richtlinien und Auslegungen der Bauaufsicht. Weiter werden die Vorgaben der europäischen Nachbarländer, die bereits ein konkretes Schutzziel definiert haben, dargestellt. Als Ergebnis stellt die Studie einen Vorschlag für Beurteilungskriterien für „brandschutztechnisch sichere“ Fassaden vor.