bluuebunny/crossref_metadata_2025 huggingface dataset:
Anaphylaxie bei rupturierter Echinokokkuszyste
Authors: Friebe Mathias , Große Düweler Christina , Theurer Sarah
Published: September 2020

Anamnese und klinischer Befund Wir berichten über eine 27-jährige syrische Patientin, die aufgrund eines Kollapses in die Notaufnahme kam. Die Anamnese war praktisch nicht zu erheben, sodass die klinische Symptomatik führend war.

Untersuchungen und Diagnose Es bestand ein Schock, mit einem Exanthem einhergehend. Zusätzlich fiel perioral Hämatin auf. Es erfolgte eine Sonografie mit Nachweis freier intraabdomineller Flüssigkeit sowie einer unklaren Veränderung im Oberbauch. Eine Ösophagogastroduodenoskopie erbrachte einen Ulkusnachweis, erklärte aber nicht das Geschehen. Die Computertomografie des Abdomens zeigte eine rupturierte Zyste.

Therapie und Verlauf Durch eine antiallergische Therapie erfolgte die Stabilisierung. Unter dem Verdacht einer Echinokokkuszyste aufgrund der Herkunft der Patientin und des Verlaufs wurde nach Gabe von Albendazol die Leberteilresektion durchgeführt. Der makroskopische Befund sowie die Histologie bestätigten den Verdacht.

Folgerung Eine unklare klinische Symptomatik, die mit einem Schock einhergeht, sollte bei Ausschluss einer Sepsis oder Blutung immer eine allergische Reaktion berücksichtigen. Kommt es zu einer Anaphylaxie, so ist immer eine Echinokokkose differenzialdiagnostisch miteinzubeziehen.
Vertrag zur prolongierten Beatmungsentwöhnung der AOK Hessen-Methodik und erste Erfahrungen
Authors: Giese Dagmar , Blau Jörg , Knüppel Walter , Neumann-Schiebener Aggi , Günther Andreas , Reinhardt Christian , Windisch Wolfram , Andreas Stefan
Published: September 2020

Hintergrund Die Zahl der Patienten, die im Verlauf einer intensivmedizinischen Behandlung von einer invasiven Beatmung entwöhnt werden müssen, hat in den vergangenen Jahren stetig zugenommen. Ein Teil hiervon bleibt dauerhaft beatmet und muss im ambulanten Bereich betreut werden. Das Gros dieser Patienten ist allerdings nicht in einem erfahrenen Weaningzentrum behandelt worden. Es ist daher wahrscheinlich, dass noch „Weaningpotenzial“ bei einem Teil der Patienten besteht.

Methoden Die AOK Hessen hat nach umfangreicher Analyse Ansatzpunkte zur Verbesserung dieser Situation entwickelt, die hier erstmalig vorgestellt werden. Als wesentlich wurden die fachliche Expertise der das Potenzial einschätzenden Ärzte (Weanigerfahrung bzw. Weaningzentrum), die Option der temporären Unterbringung der Patienten in den neu zu schaffenden Therapiezentren für außerklinische Beatmung (TAB) und die strukturierte ambulante Nachsorge erkannt.

Ergebnisse Bei den TAB handelt es sich um extrastationäre Einheiten, welche einem Weaningzentrum angeschlossen sind. Hier sollen Patienten in wohnlicher Atmosphäre betreut werden, bei denen es bisher nicht gelang, sie von der Invasivbeatmung zu entwöhnen. Der Fokus liegt dabei auf der täglichen physiotherapeutischen und logopädischen Arbeit. Hierfür wird ein Zeitraum von bis zu 6 Monaten ermöglicht, in dem sich die muskuläre und kognitive Situation verbessern soll. Im Anschluss wird dann je nach Verlauf ein erneuter Weaningversuch im Weaningzentrum unternommen.

Diskussion Das Konzept wird im folgenden Artikel ausführlich beschrieben. Erste Erfahrungen zeigen den relevanten Stellenwert der TAB in der Entwöhnung von der Beatmung.
Novel ultrathin double-balloon endoscopy for the diagnosis of small-bowel diseases: a multicenter nonrandomized study
Authors: Nakamura Masanao , Yano Tomonori , Esaki Motohiro , Oka Shiro , Mitsui Keigo , Hirai Fumihito , Kawasaki Keisuke , Fujishiro Mitsuhiro , Torisu Takehiro , Tanaka Shinji , Iwakiri Katsuhiko , Kishi Masahiro , Matsumoto Takayuki , Yamamoto Hironori
Published: September 2020

Background This study aimed to compare the markers of potential pancreatic injury during antegrade double-balloon endoscopy (DBE) using the newly developed ultrathin EN-580XP system and the conventional EN-580T system.

Methods Patients who were scheduled for antegrade DBE during daily clinical practice were enrolled. Clinical background, adverse events, and laboratory data of patients were compared between those who underwent endoscopy using the EN-580XP system and those in whom the EN-580T system was used. The primary end points were pancreatic hyperamylasemia and hyperlipasemia after DBE.

Results A total of 295 cases were registered. Pancreatic hyperamylasemia occurred in 2 of 92 patients (2.2 %) in the EN-580XP group and in 28 of 147 patients (19.1 %) in the EN-580 T diagnosis group (P < 0.001). Hyperlipasemia was significantly different between the two groups (1.1 % [EN-580XP] vs. 13.6 % [EN-580 T diagnosis]; P < 0.001). Acute pancreatitis occurred in four patients (7.1 %) in the EN-580 T therapy group. Multiple logistic regression analyses revealed that the endoscope type EN-580 T was significantly associated with pancreatic hyperamylasemia (adjusted odds ratio [OR] 8.63, 95 % confidence interval [CI] 1.97 – 37.70; P < 0.01) and hyperlipasemia (adjusted OR 13.10, 95 %CI 1.70 – 100.70; P = 0.01).

Conclusions The EN-580XP system seemed less harmful to the pancreas during antegrade DBE.
Transconjunctival and Transcaruncular Approaches to the Orbit
Authors: Wolkow Natalie , Freitag Suzanne K.
Published: September 2020

Transcaruncular and transconjunctival approaches are commonly used by ophthalmic plastic surgeons to access various orbital compartments. These approaches are versatile and may be combined with transnasal or transcranial approaches to the orbit to gain optimal access to challenging locations. A major advantage of the transcaruncular and transconjunctival approaches is the lack of a visible skin incision with excellent postoperative cosmesis. As with all orbital surgery, an in-depth knowledge of orbital anatomy and physiology, as well as meticulous hemostasis, is needed to prevent complications including globe injury, permanent vision loss, diplopia, and retrobulbar hemorrhage. This article reviews the surgical steps of these approaches. The indications for each approach and case examples are illustrated.
The “Sick-but-not-Dead” Phenomenon Applied to Catecholamine Deficiency in Neurodegenerative Diseases
Authors: Goldstein David S.
Published: September 2020

The catecholamines dopamine and norepinephrine are key central neurotransmitters that participate in many neurobehavioral processes and disease states. Norepinephrine is also the main neurotransmitter mediating regulation of the circulation by the sympathetic nervous system. Several neurodegenerative disorders feature catecholamine deficiency. The most common is Parkinson's disease (PD), in which putamen dopamine content is drastically reduced. PD also entails severely decreased myocardial norepinephrine content, a feature that characterizes two other Lewy body diseases—pure autonomic failure and dementia with Lewy bodies. It is widely presumed that tissue catecholamine depletion in these conditions results directly from loss of catecholaminergic neurons; however, as highlighted in this review, there are also important functional abnormalities in extant residual catecholaminergic neurons. We refer to this as the “sick-but-not-dead” phenomenon. The malfunctions include diminished dopamine biosynthesis via tyrosine hydroxylase (TH) and L-aromatic-amino-acid decarboxylase (LAAAD), inefficient vesicular sequestration of cytoplasmic catecholamines, and attenuated neuronal reuptake via cell membrane catecholamine transporters. A unifying explanation for catecholaminergic neurodegeneration is autotoxicity exerted by 3,4-dihydroxyphenylacetaldehyde (DOPAL), an obligate intermediate in cytoplasmic dopamine metabolism. In PD, putamen DOPAL is built up with respect to dopamine, associated with a vesicular storage defect and decreased aldehyde dehydrogenase activity. Probably via spontaneous oxidation, DOPAL potently oligomerizes and forms quinone-protein adducts with (“quinonizes”) α-synuclein (AS), a major constituent in Lewy bodies, and DOPAL-induced AS oligomers impede vesicular storage. DOPAL also quinonizes numerous intracellular proteins and inhibits enzymatic activities of TH and LAAAD. Treatments targeting DOPAL formation and oxidation therefore might rescue sick-but-not-dead catecholaminergic neurons in Lewy body diseases.
Pigmented Fungiform Papillae of the Tongue and Lingual Fimbriae as Single Presentation in Adult: A Case Report and Literature Review
Authors: Surboyo Meircurius Dwi Condro , Ernawati Diah Savitri , Parmadiati Adiastuti Endah , Marsetyo Riyan Iman
Published: September 2020

The normal variant in the oral mucosa is a nonpathological condition. Clinical examination must be carefully performed to avoid misdiagnosis as pathological condition. We reported two rare cases of pigmented fungiform papillae and lingual fimbria. Case 1 presented a 22-year-old Javanese man, with no systemic disease and several dark patches over the tongue for2 years. Case 2 presented a 21-year-old Javanese woman with dark patches over the dorsal and lateral of the tongue which had been known for over 4 to 5 months. Both patients had no systemic issues and there were no complaints about the patches. The dark patches, which appeared in both cases, were found together with linear small bumps on the ventral surface of the tongue and near the lingual frenulum. Further examination and specific treatment were not carried out, in accordance with the condition on the tongue.
Path to Perdition: Lessons Learnt from Inadequate Fixation of an L5 Fracture
Authors: Krishnan Prasad
Published: September 2020

Pedicle screw fixation is a commonly performed operation following fractures of dorsal and lumbar spines. As neurosurgeons, our primary aim is decompression of neural structures and stabilization of the vertebral column. However, careful preoperative planning is imperative to restore the alignment of the spine in sagittal and coronal planes as otherwise implant failure and progressive deformity may result. Eleven years ago, I had operated on a 12-year-old child with an L5 fracture and cauda equina syndrome where no attempt was made to either do a corpectomy and reconstruct the body or reduce it by placing screws in the fractured segment or include additional levels in the construct. Over time he had only minimal improvement in neurological status. Unfortunately, there was sequential implant failure that led to eventual removal. The serial roentgenography in this case is described.
Bowl-Shaped Naphthalimide-Annulated Corannulene as Nonfullerene Acceptor in Organic Solar Cells
Authors: Menekse Kaan , Renner Rebecca , Mahlmeister Bernhard , Stolte Matthias , Würthner Frank
Published: September 2020

An electron-poor bowl-shaped naphthalimide-annulated corannulene with branched alkyl residues in the imide position was synthesized by a palladium-catalyzed cross-coupling annulation sequence. This dipolar compound exhibits strong absorption in the visible range along with a low-lying LUMO level at –3.85 eV, enabling n-type charge transport in organic thin-film transistors. Furthermore, we processed inverted bulk-heterojunction solar cells in combination with the two donor polymers PCE–10 and PM6 to achieve open-circuit voltages up to 1.04 V. By using a blend of the self-assembled naphthalimide-annulated corannulene and PCE–10, we were able to obtain a power conversion efficiency of up to 2.1%, which is to the best of our knowledge the highest reported value for a corannulene-based organic solar cell to date.
Netting Liver Disease: Neutrophil Extracellular Traps in the Initiation and Exacerbation of Liver Pathology
Authors: Meijenfeldt Fien A. von , Jenne Craig N.
Published: September 2020

The liver plays a vital role in the immune system. Its unique position in the portal circulation and the architecture of the hepatic sinusoids, in combination with the wide-ranged population of immunocompetent cells, make the liver function as an immune filter. To aid in pathogen clearance, once challenged, the liver initiates the rapid recruitment of a wide variety of inflammatory cells, including neutrophils. These neutrophils, in conjunction with platelets, facilitate the release of neutrophil extracellular traps (NETs), which are web-like structures of decondensed nuclear DNA, histones, and neutrophil proteins. NETs function as both a physical and a chemical barrier, binding and killing pathogens circulating in the blood stream. In addition to their antimicrobial role, NETs also bind platelets, activate coagulation, and exacerbate host inflammatory response. This interplay between inflammation and coagulation drives microvascular occlusion, ischemia, and (sterile) damage in liver disease. Although direct clinical evidence of this interplay is scarce, preliminary studies indicate that NETs contribute to progression of liver disease and (thrombotic) complications. Here, we provide an overview of the pathological mechanisms of NETs in liver disease. In addition, we summarize clinical evidence for NETs in different disease etiologies and complications of liver disease and discuss the possible implications for the use of NETs as a diagnostic marker and a therapeutic target in liver disease.
The Effect of Electronic Health Record Usability Redesign on Annual Screening Rates in an Ambulatory Setting
Authors: Pierce Robert P. , Eskridge Bernie R. , Rehard LeAnn , Ross Brandi , Day Margaret A. , Belden Jeffery L.
Published: September 2020

Objectives Improving the usability of electronic health records (EHR) continues to be a focus of clinicians, vendors, researchers, and regulatory bodies. To understand the impact of usability redesign of an existing, site-configurable feature, we evaluated the user interface (UI) used to screen for depression, alcohol and drug misuse, fall risk, and the existence of advance directive information in ambulatory settings.

Methods As part of a quality improvement project, based on heuristic analysis, the existing UI was redesigned. Using an iterative, user-centered design process, several usability defects were corrected. Summative usability testing was performed as part of the product development and implementation cycle. Clinical quality measures reflecting rolling 12-month rates of screening were examined over 8 months prior to the implementation of the redesigned UI and 9 months after implementation.

Results Summative usability testing demonstrated improvements in task time, error rates, and System Usability Scale scores. Interrupted time series analysis demonstrated significant improvements in all screening rates after implementation of the redesigned UI compared with the original implementation.

Conclusion User-centered redesign of an existing site-specific UI may lead to significant improvements in measures of usability and quality of patient care.
Placing Dental Implants through Impacted Teeth to Support a Fixed Partial Denture in a Geriatric Patient as an Alternative to Invasive Extraction Surgeries
Authors: Brinkmann Jorge Cortés-Bretón , Lobato-Peña Marina , Pérez-González Fabián , Molinero-Mourelle Pedro , Sánchez-Labrador Luis , Santos-Marino Juan , López-Quiles Juan , Martínez-González Jose María
Published: September 2020

Multiple dental impactions not associated with craniofacial syndromes are a rare condition and present the dentist with a therapeutic challenge when it comes to performing surgical/restorative treatments in adult patients. This case report describes a geriatric patient with multiple impacted teeth restored by means of two different protocols. In the second quadrant, an impacted tooth was extracted followed by regeneration and placement of an implant. In the third quadrant, implants were placed though impacted teeth for restoration with a fixed partial prosthesis. Placing dental implants through impacted teeth may offer a possible therapeutic option for implant-supported restorations in middle-aged or elderly patients, for whom surgery and orthodontic traction are not possible, and/or patients who refuse to undergo more invasive extraction surgery.
Emicizumab Augments Thrombus Formation in Whole Blood from Patients with Hemophilia A under High Shear Flow Conditions
Authors: Yaoi Hiroaki , Shida Yasuaki , Kitazawa Takehisa , Shima Midori , Nogami Keiji
Published: September 2020

Background Emicizumab is a bispecific antibody to factor (F) IXa and FX that mimics the FVIIIa cofactor function. Emicizumab prophylaxis markedly decreases bleeding episodes in patients with hemophilia A (PwHAs), irrespective of the presence of FVIII inhibitors. However, thrombotic microangiopathy (TMA) was reported when repeated high doses of activated prothrombin complex concentrates (aPCC) were concomitantly used with emicizumab. Although bypassing agents (BPAs) are vital in the hemostatic treatment for PwHAs with inhibitors, the mechanism of emicizumab-related TMA remains unclear.

Aim To assess the risk of excessive thrombus formation associated with BPAs and emicizumab under high shear conditions.

Methods Perfusion flow-chamber experiments under high shear conditions were performed using whole blood from PwHAs in the presence of emicizumab without or together with FVIII or BPAs ex vivo.

Results Emicizumab (100 μg/mL) added ex vivo to whole blood from PwHAs improved defective thrombus formation in a similar manner to that observed with the addition of recombinant FVIII at the early phase, while FVIII continued to be important at the later stages. aPCC (1.2 U/mL equivalent to 100 U/kg) or recombinant FVIIa (1.1 µg/mL; equivalent to 90 µg/kg) together with emicizumab further promoted platelet interactions and fibrin formation ex vivo but did not induce excessive thrombus formation.

Conclusion Emicizumab enhanced thrombin generation at local sites and improved defective hemostasis in whole blood from PwHAs under high shear conditions. Simple concomitant use of BPAs with emicizumab did not mediate excessive thrombus formation and remains an option for hemostatic management of emicizumab-treated PwHAs with inhibitors.
Self-assembled three-dimensional macroscopic graphene/MXene-based hydrogel as electrode for supercapacitor
Authors: Zhang Luojiang , Or Siu Wing
Published: September 2020

Hydrogels with unique three-dimensional (3D) macroscopic porous architectures are attractive electrode materials for supercapacitors because of their superior electrolyte permeabilities and rapid electron/ion transports. In this letter, a cylindrical-type 3D macroscopic graphene/MXene-based hydrogel (GMH) is prepared by self-assembling laminar-structured graphene oxide (GO) and MXene (Ti3C2) nanosheets via a facile one-step hydrothermal method under the existence of ammonia water and hydrazine hydrate. GO is found to self-converge into a 3D macroscopic porous graphene framework during the hydrothermal process, while Ti3C2 nanosheets are able to prevent the graphene nanosheets from self-restacking. The as-prepared GMH shows a larger specific surface area of 161.1 m2 g−1 and a higher pore volume of 0.5 cm3 g−1 in comparison with the pure graphene hydrogel. A symmetric supercapacitor utilizing GMH as electrodes exhibits high energy densities of 9.3 Wh kg−1 and 5.7 Wh kg−1 at different power densities of 500 W kg−1 and 5000 W kg−1, respectively, as well as an outstanding long-term cycle stability with no loss in capacitance in excess of 10 000 continuous charge–discharge cycles. The strategy of preparation of a 3D macroscopic GMH is expected to realize promising high-performance hydrogel electrodes based on graphene and MXene for electrochemical energy storages.
First-principles surface energies for monoclinic Ga2O3 and Al2O3 and consequences for cracking of (AlxGa1−x)2O3
Authors: Mu Sai , Wang Mengen , Peelaers Hartwin , Van de Walle Chris G.
Published: September 2020

Crack formation limits the growth of (AlxGa1−x)2O3 epitaxial films on Ga2O3 substrates. We employ first-principles calculations to determine the brittle fracture toughness of such films for three growth orientations of the monoclinic structure: [100], [010], and [001]. Surface energies and elastic constants are computed for the end compounds—monoclinic Ga2O3 and Al2O3—and used to interpolate to (AlxGa1−x)2O3 alloys. The appropriate crack plane for each orientation is determined, and the corresponding critical thicknesses are calculated based on Griffith’s theory, which relies on the balance between elastic energy and surface energy. We obtain lower bounds for the critical thickness, which compare well with available experiments. We also perform an in-depth analysis of surface energies for both relaxed and unrelaxed surfaces, providing important insights into the factors that determine the relative stability of different surfaces. Our study provides physical insights into surface stability, crack planes, and the different degrees of crack formation in (AlxGa1−x)2O3 films for different growth orientations.
A novel modelling framework to explicitly simulate predator interaction with poison baits
Authors: Pacioni C. , Ramsey D. S. L. , Schumaker Nathan H. , Kreplins Tracey , Kennedy M. S.
Published: September 2020

Abstract ContextManagement of human–wildlife conflicts is of critical importance for both wildlife conservation and agricultural production. Population models are commonly used to simulate population dynamics and their responses to management actions. However, it is essential that this class of models captures the drivers and mechanisms necessary to reliably forecast future system dynamics. AimsWe aimed to develop a flexible modelling framework with the capacity to explicitly simulate individual interactions with baits (with or without the presence of other management tools), for which parameter estimates from field data are available. We also intended for the model to potentially accommodate multi-species interaction and avoidance behaviours. MethodsWe expanded an existing spatially explicit, individual-based model to directly simulate bait deployment, animal movements and bait consumption. We demonstrated the utility of this model using a case study from Western Australia where we considered two possible exclusion-fence scenarios, namely, the completion of a landscape-scale and smaller-scale fences. Within each of these proposed cells, using data obtained from a camera-trap study, we evaluated the performance of two levels of baiting to control wild dogs (Canis familiaris), in contrast with the option of no control. ResultsThe present study represents a substantial step forward in accurately modelling predator dynamics. When applying our model to the case study, for example, it was straightforward to investigate whether outcomes were sensitive to the bait-encounter probability. We could further explore interactions between baiting regimes and different fence designs and demonstrate how wild dog eradication could be achieved in the smaller cell under the more intense control scenarios. In contrast, the landscape-scale fence had only minor effects unless it was implemented as a preventive measure in an area where wild dogs were not already established. ConclusionsThe new component of the model presented here provides fine-scale control of single components of individual–bait interactions. ImplicationsThe effect of management actions (e.g. lures) that affect this process can be easily investigated. Multi-species modelling and avoidance behaviours can readily be implemented, making the present study widely relevant for a range of contexts such as multi-species competition or non-target bait uptake.
Preliminary evaluation of biomechanical modeling of lung deflation during minimally invasive surgery using pneumothorax computed tomography scans
Authors: Lesage Anne-Cécile , Rajaram Ravi , L Tam Alda , Rigaud Bastien , K Brock Kristy , C Rice David , Cazoulat Guillaume
Published: September 2020

During minimally invasive surgery (MIS) for lung tumor resection, the localization of tumors or nodules relies on visual inspection of the deflated lung on intra-procedural video. For patients with tumors or nodules located deeper in the lung, this localization is not possible without prior invasive marking techniques. In efforts to avoid the increase of complication rates associated with these invasive techniques, this study investigates the use of biomechanical modeling of the lung deflation to predict the tumor localization during MIS, solely based on a pre-operative computed tomography (CT) scan. The feasibility of the proposed approach is evaluated using preliminary data from six patients who presented with pneumothorax after lung biopsy and underwent chest tube insertion. For each patient, a hyperelastic finite-element model of the lung was created from the CT scan showing the re-inflated lung. Boundary conditions were applied on the lung surface to simulate the gravity and insufflation of carbon dioxide in the chest. The impact of adding rigid constraints around the main airway was also evaluated. To evaluate the accuracy of the model in predicting lung tissues or potential tumor displacement, at least five corresponding landmarks were identified for each patient in the CT scans of their deflated and re-inflated lungs. Using these landmarks, target localization errors (TLE) were measured for different sets of pressure applied to lung surface and shear modulus. For five patients, the minimum achieved mean TLE was inferior to 9 mm using patient-specific parameters and inferior to 10 mm using the same parameterization. The predicted and ground truth deflated lung surfaces presented visually a relatively good agreement. The proposed approach thus appears as a promising tool for integration in future lung surgery image-guidance systems.
Efficient and multifunctional terahertz polarization control device based on metamaterials*
Authors: Jiao Xiao-Fei , Zhang Zi-Heng , Xu Yun , Song Guo-Feng
Published: September 2020

Terahertz polarization devices are an important part of terahertz optical systems. Traditional terahertz polarization devices rely on birefringent crystals, and their performances are limited by the material structures. In this work, we theoretically demonstrate that the metamaterial consisting of the medium and the periodic metal band embedded in the medium can control broadband polarization effectively. The transmission length of the subwavelength waveguide mode gives rise to a broadband transmission peak. The resonant cavity structure formed by the dielectric layer and the waveguide layer possesses a high transmission efficiency. By optimizing the metamaterial structure parameters, we design a high-efficient (>90%) quarter-wave plate over a frequency range of 0.90 THz–1.10 THz and a high-efficient (>90%) half-wave plate over a frequency range of 0.92 THz–1.02 THz. Besides, due to the anisotropy of the structure, the metamaterials with the same structural parameters can achieve the function of the polarized beam splitting with an efficiency of up to 99% over a frequency range of 0.10 THz–0.55 THz. Therefore, the designed metamaterial has a multifunctional polarization control effect, which has potential applications in the terahertz integrated polarization optical system.
Energy stored in nanoscale water capillary bridges formed between chemically heterogeneous surfaces with circular patches*
Authors: Tang Bin-Ze , Yu Xue-Jia , Buldyrev Sergey V. , Giovambattista Nicolas , Xu Li-Mei
Published: September 2020

The formation of nanoscale water capillary bridges (WCBs) between chemically heterogeneous (patchy) surfaces plays an important role in different scientific and engineering applications, including nanolithography, colloidal aggregation, and bioinspired adhesion. However, the properties of WCB of nanoscale dimensions remain unclear. Using molecular dynamics simulations, we investigate the geometrical and thermodynamic properties of WCB confined between chemically heterogeneous surfaces composed of circular hydrophilic patches on a hydrophobic background. We find that macroscopic capillary theory provides a good description of the WCB geometry and forces induced by the WCB on the confining surfaces even in the case of surface patches with diameters of only 4 nm. Upon stretching, the WCB contact angle changes from hydrophobic-like values (θ > 90°) to hydrophilic-like values (θ < 90°) until it finally breaks down into two droplets at wall separations of ∼ 9–10 nm. We also show that the studied nanoscale WCB can be used to store relevant amounts of energy E
P and explore how the walls patch geometry can be improved in order to maximize E
P. Our findings show that nanoscale WCB can, in principle, be exploited for the design of clean energy storage devices as well as actuators that respond to changes in relative humidity. The present results can also be of crucial importance for the understanding of water transport in nanoporous media and nanoscale engineering systems.
Controlling the light wavefront through a scattering medium based on direct digital frequency synthesis technology*
Authors: Yuan Yuan , Sun Min-Yuan , Bi Yong , Gao Wei-Nan , Zhang Shuo , Zhang Wen-Ping
Published: September 2020

Phase modulation is a crucial step when the frequency-based wavefront optimization technique is exploited to measure the optical transmission matrix (TM) of a scattering medium. We report a simple but powerful method, direct digital frequency synthesis (DDS) technology to modulate the phase front of the laser and measure the TM. By judiciously modulating the phase front of a He–Ne laser beam, we experimentally generate a high quality focus at any targeted location through a 2 mm thick 120 grit ground glass diffuser, which is commercially used in laser display and laser holographic display for improving brightness uniformity and reducing speckle. The signal to noise ratio (SNR) of the clear round focus is ∼ 50 and the size is about 44 μm. Our study will open up new avenues for enhancing light energy delivery to the optical engine in laser TV to lower the power consumption, phase compensation to reduce the speckle noise, and controlling the lasing threshold in random lasers.
Results of dark matter search using the full PandaX-II exposure *
Authors: Wang Qiuhong , Abdukerim Abdusalam , Chen Wei , Chen Xun , Chen Yunhua , Cheng Chen , Cui Xiangyi , Fan Yingjie , Fang Deqing , Fu Changbo , Fu Mengting , Geng Lisheng , Giboni Karl , Gu Linhui , Guo Xuyuan , Han Ke , He Changda , Huang Di , Huang Yan , Huang Yanlin , Huang Zhou , Ji Xiangdong , Ju Yonglin , Li Shuaijie , Liu Huaxuan , Liu Jianglai , Ma Wenbo , Ma Yugang , Mao Yajun , Meng Yue , Ni Kaixiang , Ning Jinhua , Ning Xuyang , Ren Xiangxiang , Shang Changsong , Si Lin , Shen Guofang , Tan Andi , Wang Anqing , Wang Hongwei , Wang Meng , Wang Siguang , Wang Wei , Wang Xiuli , Wang Zhou , Wu Mengmeng , Wu Shiyong , Wu Weihao , Xia Jingkai , Xiao Mengjiao , Xie Pengwei , Yan Binbin , Yang Jijun , Yang Yong , Yu Chunxu , Yuan Jumin , Yuan Ying , Zeng Xinning , Zhang Dan , Zhang Tao , Zhao Li , Zheng Qibin , Zhou Jifang , Zhou Ning , Zhou Xiaopeng , (PandaX-II Collaboration)
Published: September 2020

We report the dark matter search results obtained using the full 132 ton·day exposure of the PandaX-II experiment, including all data from March 2016 to August 2018. No significant excess of events is identified above the expected background. Upper limits are set on the spin-independent dark matter-nucleon interactions. The lowest 90% confidence level exclusion on the spin-independent cross section is 2.2 × 10−46 cm2 at a WIMP mass of 30 GeV/c2.
Decoding the covert shift of spatial attention from electroencephalographic signals permits reliable control of a brain-computer interface
Authors: Reichert Christoph , Dürschmid Stefan , Bartsch Mandy V , Hopf Jens-Max , Heinze Hans-Jochen , Hinrichs Hermann
Published: September 2020

Objective. One of the main goals of brain-computer interfaces (BCI) is to restore communication abilities in patients. BCIs often use event-related potentials (ERPs) like the P300 which signals the presence of a target in a stream of stimuli. The P300 and related approaches, however, are inherently limited, as they require many stimulus presentations to obtain a usable control signal. Many approaches depend on gaze direction to focus the target, which is also not a viable approach in many cases, because eye movements might be impaired in potential users. Here we report on a BCI that avoids both shortcomings by decoding spatial target information, independent of gaze shifts. Approach. We present a new method to decode from the electroencephalogram (EEG) covert shifts of attention to one out of four targets simultaneously presented in the left and right visual field. The task is designed to evoke the N2pc component—a hemisphere lateralized response, elicited over the occipital scalp contralateral to the attended target. The decoding approach involves decoding of the N2pc based on data-driven estimation of spatial filters and a correlation measure. Main results. Despite variability of decoding performance across subjects, 22 out of 24 subjects performed well above chance level. Six subjects even exceeded 80% (cross-validated: 89%) correct predictions in a four-class discrimination task. Hence, the single-trial N2pc proves to be a component that allows for reliable BCI control. An offline analysis of the EEG data with respect to their dependence on stimulation time and number of classes demonstrates that the present method is also a workable approach for two-class tasks. Significance. Our method extends the range of strategies for gaze-independent BCI control. The proposed decoding approach has the potential to be efficient in similar applications intended to decode ERPs.
Aptamers recognizing fibronectin confer improved bioactivity to biomaterials and promote new bone formation in a periodontal defect in rats
Authors: Parisi Ludovica , Rivara Federico , Costa Camila A , Abuna Rodriguo PF , Palioto Daniela B , Macaluso Guido M
Published: September 2020

The use of alloplastic materials in periodontal regenerative therapies is limited by their incapacity to establish a dynamic dialog with the surrounding milieu. The aim of the present study was to control biomaterial surface bioactivity by introducing aptamers to induce the selective adsorption of fibronectin from blood, thus promoting platelets activation in vitro and bone regeneration in vivo. A hyaluronic acid/polyethyleneglycole-based hydrogel was enriched with aptamers selected for recognizing and binding fibronectin. In vitro, the capacity of constructs to support osteoblast adhesion, as well as platelets aggregation and activation was assessed by chemiluminescence within 24 h. Matrices were then evaluated in a rat periodontal defect to assess their regenerative potential by microcomputed tomography (µCT) and their osteogenic capacity by Luminex assay 5, 15 and 30 d postoperatively. Aptamers were found to confer matrices the capacity of sustaining firm cell adhesion (p = 0.0377) and to promote platelets activation (p = 0.0442). In vivo, aptamers promoted new bone formation 30 d post-operatively (p < 0.001) by enhancing osteoblastic lineage commitment maturation. Aptamers are a viable surface modification, which confers alloplastic materials the potential capacity to orchestrate blood clot formation, thus controlling bone healing.
Mesenchymal stem cell-derived extracellular matrix (mECM): a bioactive and versatile scaffold for musculoskeletal tissue engineering
Authors: Zhang Xiurui , Liu Yuwei , Clark Karen L , Padget Anne-Marie , Alexander Peter G , Dai Jianwu , Zhu Weimin , Lin Hang
Published: September 2020

Mesenchymal stem cell-derived extracellular matrix (mECM) has received increased attention in the fields of tissue engineering and scaffold-assisted regeneration. mECM exhibits many unique characteristics, such as robust bioactivity, biocompatibility, ease of use, and the potential for autologous tissue engineering. As the use of mECM has increased in musculoskeletal tissue engineering, it should be noted that mECM generated from current methods has inherited insufficiencies, such as low mechanical properties and lack of internal architecture. In this review, we first summarize the development and use of mECM as a scaffold for musculoskeletal tissue regeneration and highlight our current progress on moving this technology toward clinical application. Then we review recent methods to improve the properties of mECM that will overcome current weaknesses. Lastly, we propose future studies that will pave the road for mECM application in regenerating tissues in humans.
Freeing land from biofuel production through microalgal cultivation in the Neotropical region
Authors: Correa Diego F , Beyer Hawthorne L , Possingham Hugh P , García-Ulloa John , Ghazoul Jaboury , Schenk Peer M
Published: September 2020

Biofuel production is a key strategy for reducing CO2 emissions globally and is expected to increase substantially in the coming decades, particularly in tropical developing countries. The adoption of sustainable biofuel production technologies that do not place large demands on agricultural or forested lands, has the potential to make a substantial contribution to decreasing greenhouse gas emissions while reducing biodiversity losses and degradation of native ecosystems resulting from high demand for land. With their high productivity per unit area and ability to grow on non-arable lands, microalgal biofuel production systems could become a major sustainable alternative to biofuel production from food crops (first-generation biofuels). However, the potential impacts of microalgal biofuels on food production, biodiversity, and carbon storage, compared to other biofuel production alternatives, are largely unknown. In the present study, the most suitable areas for siting microalgae production farms to fulfill 30% of future transport energy demands were determined within four Neotropical countries with high population densities and high importance for agricultural expansion and biodiversity conservation globally (Colombia, Ecuador, Panama, and Venezuela). These results were contrasted with the best areas for siting oil palm and sugarcane crops to fulfill the same target in future transport energy demands. Microalgal production systems offer the most sustainable alternative for future biofuel production within the Neotropics. Meeting 30% of future transport energy demands with microalgal biofuels reduced land area requirements by at least 52% compared to oil palm and sugarcane. Furthermore, microalgal biofuel production reduced direct competition with agricultural lands, biodiverse areas, and carbon-rich systems within countries, with little overlap with the biodiverse and carbon-rich rainforests. This study can guide decision making towards the identification and adoption of more sustainable biofuel production alternatives in the Neotropics, helping in avoiding unnecessary environmental impacts from biofuel expansion in the region.
Tribological performance of surface texturing in mechanical applications—a review
Authors: Lu Ping , Wood Robert J K
Published: September 2020

Surface textures have been of great interest within the tribology community with nearly 1500 papers published on this topic in the past two decades. With the pursuit of low emissions and environmental sustainability, the application of surface texturing to mechanical systems to lower friction and control wear is attracting increasing attention. There is no doubt that certain textured surfaces can have a beneficial effect on tribological performance but it is widely agreed that the optimization of textures should be carried out based on specific requirements of applications. The purpose of this review article is to summarize the current state of the art in surface texturing applied to mechanical applications (cutting tools, piston-ring & cylinder liners, sealing and journal bearings) from the following aspects: application requirements, numerical/experimental testing and validation, and tribological performance of textured surfaces (wear and friction), as well as the limitations in texture designs when applied to certain applications. Patterns/grooves in the micron-scale are the most typical shapes been studied, and benefits of partial texturing are applicable for most of these mechanical applications. Friction reduction of up to 34.5% in cutting tools, 82% in piston-ring & cylinder-liners, 65% in seals and 18% in journal bearings have been observed by experimental tests. Based on primary evidence from the literature, the last section provides general suggestions on current gaps in understanding and modelling and suggestions for future research directions.
Mono- to few-layer non-van der Waals 2D lanthanide-doped NaYF4nanosheets with upconversion luminescence
Authors: Clarke Christian , Singh Mandeep , Tawfik Sherif Abdulkader , Xu Xiaoxue , Spencer Michelle J S , Ramanathan Rajesh , Reineck Philipp , Bansal Vipul , Ton-That Cuong
Published: September 2020

NaYF4is an efficient host material for lanthanide-based upconversion luminescence and has attracted immense interest for potential applications in photovoltaics, lasers and bioimaging. However, being a non-van der Waals (non-vdW) material, there have been thus far no reports on exfoliation of bulk NaYF4to nanosheets and their upconversion luminescence properties. Here, we demonstrate for the first time the fabrication of lanthanide-containing NaYF42D nanosheets using a soft liquid-phase exfoliation method and report on their optical, electronic and chemical characteristics. The nanosheets exfoliated from NaYF4:Yb,Er microcrystals consisting mainly ofβ-NaYF4become enriched inα-NaYF4post exfoliation and have a large micron-sized planar area with a preferential (100) surface orientation. X-ray absorption spectroscopy confirms that both Yb and Er doping ions are retained in the exfoliated nanosheets. Through centrifugation, NaYF42D nanosheets are successfully obtained with thicknesses ranging from a monolayer to tens of layers. Optical analysis of individual nanosheets shows that they exhibit both optical down-conversion and upconversion properties, albeit with reduced emission intensities compared with the parent microparticles. Further exploration of their electronic structure by density functional theory (DFT) calculations and photoelectron spectroscopy reveals the formation of surface F atom defects and a shrinkage of the electronic bandgap in ultrathin nanosheets. Our findings will trigger further interest in non-vdW 2D upconversion nanomaterials.
Spectral emissivity inversion of quartz composite ceramics under hypersonic airflow collision
Authors: Cai Pengcheng , Shuang Li , Shi Jing , Xin Minsi , Tan Yong , Cai Hongxing
Published: September 2020

In this paper, the radiation spectra of quartz composite ceramic thermal protective materials in a pneumatic environment were measured in a plasma arc wind tunnel experiment. Spectral emissivities and material temperature at varying airflow speeds were calculated based on the algorithm of slow variation properties of emissivity. The inversion results show that the spectral emissivity reaches its maximum at a maximum airflow velocity of Mach 10. Emissivity uncertainty caused by the spectral measurement was analyzed. Relative error was determined by comparing real and calculated emissivities from Standard blackbody radiation spectrums at 2298 K in the wavelength range of 420–900 nm and 1573 K for 1200–2400 nm. Results obtained by the algorithm of slow variation properties for emissivity show that the maximum relative error in 420–900 nm is 3.3% and the average relative error is 2.7%; the maximum relative error for 1400–2400 nm is 4.1% and the average relative error is 2.1%. This provides a new method for the study of material emissivity under hypersonic flow collision aerodynamic heating conditions.
A comprehensive study of the magnetic concentrating sensor for the damage detection of steel wire ropes
Authors: Zhang Yiqing , Jing Luyang , Chen Chengjun , Bai Xiaorui , Tan Jiwen
Published: September 2020

Magnetic flux leakage (MFL) method is an important way to detect the fault of steel wire ropes and the sensor for the collection of MFL plays a vital role in the damage detection. Among varied sensors based on MFL method, the magnetic concentrating sensor shows a lot of advantages in the detection of wire ropes. The use of the magnetic concentrator can assist the magnetic sensitive component to detect the MFL and reduce the number of the Hall components. The lift-off of the magnetic concentrating sensor can also be set to a feasible value which is easier to be ensured in the practical application. Although many researches on the magnetic concentrating sensor have been carried out, few of them have a comprehensive and thorough investigation, which should include the simulation analysis, the prototype design, the broken wire experiment and the comparison with other commonly used sensors. In this paper, a magnetic concentrating sensor is developed and compared with a Hall array sensor through both simulation and experiments. Firstly, the three-dimensional models of the magnetic concentrating sensor and the Hall array sensor are designed and their performance on collecting MFL is analyzed through finite element method (FEM). Secondly, the prototypes of the two kinds of sensors are designed according to the simulation results and their corresponding processing circuits are made. Finally, the effectiveness of the two sensors is evaluated by broken wire experiments with different rope diameters. The simulation and experimental results demonstrate that the magnetic concentrating sensor achieves a higher sensitivity and signal-to-noise ratio (SNR) than the Hall array sensor with less Hall components and simpler pre-processing circuit.
The impact of submerged friction stir processing on the friction stir welded dissimilar joints
Authors: Mabuwa Sipokazi , Msomi Velaphi
Published: September 2020

The submerged friction stir processing (SFSP) technique was employed on the prior friction stir welded (FSW) AA6082/AA8011 dissimilar aluminum alloy joints. The tap water with room temperature was kept at 40 mm depth throughout the processing. The AA6082 was kept at the advancing side during FSW and SFSP process and this was done to enhance the strength of the joint. The SFSP joints were studied comparatively with the FSW joints. The sampling position was also studied for both the FSW joint and SFSP joint. The employment of the submerged friction stir processing resulted in the microstructural grain size refinement. The tensile strength of the SFSP joint was found to be higher than that of AA8011 base metal but lower than that of AA6082 base metal. The tensile strength of the FSW joint was found to be lower than that of both base metals. There was a clear correlation between the tensile properties and the grain size refinement. The SFSP joint exhibited good microhardness properties compared to the FSW joint.
Deep learning of chaos classification
Authors: Seok Lee Woo , Flach Sergej
Published: September 2020

We train an artificial neural network which distinguishes chaotic and regular dynamics of the two-dimensional Chirikov standard map. We use finite length trajectories and compare the performance with traditional numerical methods which need to evaluate the Lyapunov exponent (LE). The neural network has superior performance for short periods with length down to 10 Lyapunov times on which the traditional LE computation is far from converging. We show the robustness of the neural network to varying control parameters, in particular we train with one set of control parameters, and successfully test in a complementary set. Furthermore, we use the neural network to successfully test the dynamics of discrete maps in different dimensions, e.g. the one-dimensional logistic map and a three-dimensional discrete version of the Lorenz system. Our results demonstrate that a convolutional neural network can be used as an excellent chaos indicator.