bluuebunny/crossref_metadata_2025 huggingface dataset:
Emotion based human-robot interaction
Authors: Berns Karsten , Zafar Zuhair
Published: April 2018

Human-machine interaction is a major challenge in the development of complex humanoid robots. In addition to verbal communication the use of non-verbal cues such as hand, arm and body gestures or mimics can improve the understanding of the intention of the robot. On the other hand, by perceiving such mechanisms of a human in a typical interaction scenario the humanoid robot can adapt its interaction skills in a better way. In this work, the perception system of two social robots, ROMAN and ROBIN of the RRLAB of the TU Kaiserslautern, is presented in the range of human-robot interaction.
Stability of digital feedback control systems
Authors: Larkin Eugene , Bogomolov Alexey , Feofilov Sergey
Published: April 2018

Specific problems arising, when Von Neumann type computer is used as feedback element, are considered. It is shown, that due to specifics of operation this element introduce pure lag into control loop, and lag time depends on complexity of algorithm of control. Method of evaluation of runtime between reading data from sensors of object under control and write out data to actuator based on the theory of semi- Markov process is proposed. Formulae for time characteristics estimation are obtained.

Lag time characteristics are used for investigation of stability of linear systems. Digital PID controller is divided onto linear part, which is realized with a soft and pure lag unit, which is realized with both hardware and software. With use notions amplitude and phase margins, condition for stability of system functioning are obtained. Theoretical results are confirm with computer experiment carried out on the third-order system.
Maintenance problems of PWM-inverters in power networks with distributed generation
Authors: Kuznetsov Pavel , Solyonyj Sergej , Sychev Yuriy , Abramovich Boris
Published: April 2018

This article observes maintenance problems of PWM-Electric Drive in Power Networks with distributed generation (DG). Compared to conventional centralized networks harmonics disturbances and non-sinusoidal waveforms happen faster in DG networks due to bigger amount of non-linear loads (Frequency and Power AC and DC Converters, PWM-Electric Drive, etc.). As a result, general stability, power quality and uninterruptible power supply can be disturbed. In order to prevent these factors a complex of power conditioning measures is proposed in this article. It demonstrates the possible influence of Active Power Filters with selective harmonics compensation function implementation together with developed controller and preventive algorithm. Almost all modelling was performed in Matlab/Simulink software.
Mathematical support and software for data processing in robotic neurocomputer systems
Authors: Romanchuk Vitaliy
Published: April 2018

The paper addresses classification and formal definition of neurocomputer systems for robotic complexes, based on the types of associations among their elements. We suggest analytical expressions for performance evaluation in neural computer information processing, aimed at development of methods, algorithms and software that optimize such systems.
Processing models for conflicting user requests in ubiquitous corporate smart spaces
Authors: Levonevskiy Dmitriy , Vatamaniuk Irina , Saveliev Anton
Published: April 2018

This paper considers processing of conflicting user requests in ubiquitous corporate smart spaces. The formulated problem consists in the contradiction between the limitation of available smart space resources to perform the conflicting user requests and necessity to provide the proper quality of service in corporate smart spaces. The principles of constructing the simulation model are described. The experiments were carried out basing on a model of the SPIIRAS digital signage service. Several task management strategies are discussed, an assessment of their effectiveness is given. The research is aimed at improving the quality of service and user experience in human-computer interaction within the corporate smart spaces.
Investigation of the dynamical characteristics of the lower-limbs exoskeleton actuators
Authors: Yatsun Andrey , Karlov Andrey , Malchikov Andrey , Jatsun Sergey
Published: April 2018

Authors present results of the theoretical modeling and experimental tests of the low-cost DС- motors, used in lower limb powered exoskeleton. Actuators work in difficult regime and it is important to achieve desired parameters, even for not robust motors. Results give us information and methods and means of experimental determination of the main characteristics of the robot‘s actuators. It gives possibility to tune control system and the whole system to achieve optimal walking regime.
Synthesis of structural scheme of drive of adaptive multiple-link gripper
Authors: Bogdanov Aleksej , Permyakov Aleksandr , Zhdanova Yulija
Published: April 2018

The problem of construction of drive of multiple-link gripper capable to operate with human infrastructure objects is considered in the article. Technical specifications of structural scheme of actuating link group of a gripper are determined with reference to analysis of human hand finger bones motion. Structural scheme of system of motion transmission to the output links that realizes group drive and does not have kinematic correspondence of links is recommended. Synthesis of structural scheme is accomplished on the basis of providing of adaptability of output links location to the grasped object surface contour. The key point of the construction is variability of output link according to the interaction with grasped object. This is provided by passive power connections which are initiated between output links and motion transmission system links. Sequence of functioning of actuating link group is represented. Keywords: synthesis, structural scheme, drive, multiple-link gripper, actuating link group, passive power connections.
State observer design for a walking in-pipe robot
Authors: Savin Sergei , Jatsun Sergey , Vorochaeva Ludmila
Published: April 2018

In this paper, a state observer design for a walking in-pipe robot is studied. The necessity of using a state observer is related to the fact that sensors have limited accuracy and are prone to producing noise. This is especially problematic for in-pipe walking robots, since they use model-based control and require accurate information of their current state. The paper shows that an iterative state observer based on solving Riccati equation provides significant improvements in the behaviour of the control system. It allows to smooth out the spikes in the control actions requested by controller and to minimize tremor of the robot links. In order to study the behaviour of the observer when different sensors are used, a performance function was introduced. It was shown that the observer allows to improve the performance of the control system for a wide range of sensor parameters. Additionally, it was shown that the introduction of the observer allows to choose higher feedback controller gains, enabling more precise control. Simulations on the full robot model, taking into account mechanical constraints and contact forces showed that the linear observer is capable of improving the behaviour of the control system of the walking robot, if measurements of the reaction forces are provided. The effects that the noise and quantization in the reaction forces measurements have on the behaviour of the state observer is studied.
Remote control library and GUI development for Russian crawler robot Servosila Engineer
Authors: Mavrin Ilya , Lavrenov Roman , Svinin Mikhail , Sorokin Sergey , Magid Evgeni
Published: April 2018

Recently a large variety of robots are available on the global market for a reasonable price. Often it turns out that even though a robot has a high-quality hardware and architecture, an original software of the robot may have a number of drawbacks or lacks some important features, which are required for a particular application of the robot. In such cases a user may decide to implement new libraries and functionalities using a provided by a manufacturer application programming interfaces as in most cases code of a commercial robot system is not an open-source. A number of our ongoing research projects concentrate on applications of various robots in urban search and rescue operations, and in most of these projects utilize Russian crawler robot Servosila Engineer. This paper describes the development of a new ROS-based control software and graphical user interface for Servosila Engineer robot.
Blockchain-based framework for ontology-oriented robots’ coalition formation in cyberphysical systems
Authors: Teslya Nikolay , Smirnov Alexander
Published: April 2018

The creation and functioning of intelligent robots coalition is impossible without the organization of an information interaction environment between them. To solve this problem, it is proposed to use the concept of cyberphysical framework, which involves the unification of physical and cyber (virtual) environments. Intelligent robots can interact with each of the environments. The paper proposes methodology of the cyber physical smart space creation for the intelligent robots’ coalition formation and functioning, based on the concept of the “blackboard” with the support of smart contracts over the blockchain technology. It provides a new approach to the distribution of sensory, computational, information-control and service tasks between intelligent robots, embedded devices, fixed service equipment, cloud computing and information resources.
Issues of physical interaction of unmanned aircraft manipulators with ground objects
Authors: Nguyen Vinh , Solenaya Oksana , Smirnov Petr
Published: April 2018

Adding an onboard manipulation system to an unmanned aerial vehicle (UAV) significantly complicates framework, functioning algorithms, and leads to an increase in overall dimensions. The physical interaction of the manipulator with objects influences to unstabilization of UAV, which in turn leads to difficulties in positioning the UAV and reduces the accuracy of gripper motion. In addition, the physical interaction of the manipulator with objects requires increased power resources of UAVs. The article analyzes modern research of UAVs with a manipulator, including flight control problems, avoidance of contact with the earth, surrounding space, as well as manipulations with the captured object. On the basis of the analysis, a list of new problems arising in the physical interaction of UAVs with objects through an embedded manipulator is formulated.
A decentralised solution for coordinating decisions in large-scale autonomic systems
Authors: Melekhova Olga , Malenfant Jacques , Mescheriakov Roman , Chueshev Aleksandr
Published: April 2018

In this paper, we address the large-scale coordination of decisions impacting the consumption of a common shared resource of limited capacity by managed elements. We propose a decentralised token-based scheme, where each token represents a share of the resource. Our token-based protocol is meant to provide statistical guarantees on the average total resource usage and the average lateness of node actions due to the coordination. Experiments with the coordination of 10.000 autonomic managers have shown very good results for large spectrum of parameter values and system’s regimes.
Robust anti-windup control for marine cyber-physical systems
Authors: Kakanov Mikhail , Kaliuzhny Mikhail , Borisov Oleg , Gromov Vladislav , Vlasov Sergey , Somov Sergey , Pyrkin Anton
Published: April 2018

In this paper the robust output control with anti-windup compensation and its implementation to the robotic boat are addressed. The detailed control design and stability analysis of the closed-loop systems are provided in the work. Extensive experimental verification of the dynamic positioning system based on various modifications of the basic controller is carried out by means of robotic boat. The corresponding experimental results are presented and analysed.
Smartphone-based tourist trip planning system: a context-based approach to offline attraction recommendation
Authors: Mikhailov Sergei , Kashevnik Alexey
Published: April 2018

The paper presents a tourist trip planning system that is aimed at offline attractions recommendation for a tourist based on current situation in the region and user profiles. Authors present the related work analysis in this area and based on this analysis develop the reference model of the proposed system and describe implementation that is based on previously developed Tourist Assistant — TAIS.
Evolution of features of chronic pancreatitis during endoscopic ultrasound-based surveillance of individuals at high risk for pancreatic cancer
Authors: Konings Ingrid , Cahen Djuna , Harinck Femme , Fockens Paul , van Hooft Jeanin , Poley Jan-Werner , Bruno Marco
Published: April 2018

Background and study aims During endoscopic ultrasound (EUS)-based pancreatic ductal adenocarcinoma (PDAC)-surveillance in asymptomatic individuals, features of chronic pancreatitis (CP) are often detected. Little is known about the prevalence and progression of these features. The aim of this study was to quantify these features, assess the interobserver agreement, assess possible associated factors, and assess the natural course during 3 years of follow-up.

Patients and methods Two experienced endosonographers reviewed anonymized sequential EUS videos of participants in PDAC surveillance that were obtained in 2012 and 2015 for features of CP. Descriptives, agreement analyses, univariate and multivariate analyses for possible risk factors, and repeated measures analyses to assess intra-individual changes over time were performed.

Results A total of 42 EUS videos of 21 participants were reviewed. Any feature of CP was present in 86 % (2012) and 81 % (2015) of participants, with a mean of 2.5 features per individual. The overall interobserver agreement was almost perfect at 83 %. No baseline factors were significantly associated with features of CP. Features did not change over time, except for hyperechoic foci without shadowing, which decreased intra-individually (β = – 1.6, P = 0.005).

Conclusions This blinded study shows features of CP to be highly prevalent in individuals at high risk of developing pancreatic cancer. No baseline factors were associated with presence of these features. CP features did not increase intra-individually over a 3-year period. Longer follow-up and pathological examination of pancreatic resection specimens will be essential to learn whether EUS detection and follow-up of these CP features bear clinical relevance.
Adipositas in der Revisionsendoprothetik des Kniegelenks – eine systematische Literaturübersicht und rechtliche Bewertung
Authors: Ploeger Milena , Müller Norbert , Wirtz Dieter , Kohlhof Hendrik
Published: April 2018

Hintergrund Über die letzten Jahre zeigt sich ein deutlicher Trend hin zum Übergewicht innerhalb der deutschen Bevölkerung. Folglich wurde auch eine deutliche Zunahme der Anzahl adipöser Patienten in der Primärendoprothetik beschrieben. Als Folge der hohen Anzahl von primärendoprothetischen Gelenkersätzen steigt aktuell auch die Zahl der revisionsendoprothetischen Eingriffe, sodass auch hier mit einer Zunahme der Anzahl übergewichtiger Patienten zu rechnen ist. Trotz dieser Tatsachen beschreiben viele Prothesenhersteller Adipositas als eine relative, teilweise sogar absolute Kontraindikation, und auch die Datenlage in der Revisionsendoprothetik bez. Adipositas und deren Auswirkungen ist gering. Ziel dieses systematischen Reviews ist es daher, Fragen bez. der Re-Revisionsoperation, der Infektionsrate, des postoperativen Outcomes, der Implantatüberlebensrate und der rechtlichen Konsequenzen bei adipösen Patienten in der Revisionsendoprothetik des Kniegelenks zu erörtern.

Patienten/Material und Methoden Basierend auf einem systematischen Review der Datenbank PubMed identifizierten wir Studien, die sich mit der Thematik Adipositas und Übergewicht in der Wechselendoprothetik des Kniegelenks befassten. Die Bewertung der Studienqualität erfolgte anhand des Evidenzgrades sowie des modifizierten Jadad-Scores. Zusätzlich wurden die Studien nach Fallzahl, Alter, Größe, Gewicht, Geschlecht und Follow-up-Zeit analysiert. Zusätzlich erfolgte eine Analyse des aktuellen rechtlichen Aspekts.

Ergebnisse und Schlussfolgerung Insgesamt wurden aus n = 118 Suchergebnissen 5 Studien eingeschlossen. Der durchschnittliche Jadad-Score lag bei 1, das durchschnittliche Level of Evidence bei 3. Bezüglich der Infektionsrate und Revisionsoperationsrate zeigten 2 Studien deutlich schlechtere Werte für adipöse Patienten in der Wechselendoprothetik. Patienten mit einer morbiden Adipositas hatten in der Literatur ein deutlich erhöhtes Risiko für Wundheilungsstörungen und periprothetische Gelenkinfekte. Drei Studien gaben schlechtere Werte für adipöse Patienten an bez. des postoperativen Outcomes bei Funktion und Schmerz. Der rechtliche Aspekt wurde in keiner der 5 Studien genauer erörtert. Insgesamt ist die Datenlage bez. der Fragestellung gering und sehr heterogen, sodass die Gruppenbildung der 5 Studien nur bedingt vergleichbar ist. Insgesamt weisen jedoch die Ergebnisse des Reviews darauf hin, dass Adipositas auch in der Revisionsendoprothetik des Kniegelenks eine prognostisch ungünstige Einflussgröße ist. Rechtlich gesehen muss der Faktor Adipositas/Übergewicht in der Aufklärung der Wechselendoprothetik zwingend berücksichtigt werden, da sonst die Möglichkeit besteht, dass die Aufklärung nicht dem zu fordernden Fachstandard entsprechend erfolgt.
Quantification and Brain Targeting of Eugenol-Loaded Surface Modified Nanoparticles Through Intranasal Route in the Treatment of Cerebral Ischemia
Authors: Ahmad Niyaz , Ahmad Rizwan , Alam Md , Ahmad Farhan
Published: April 2018

Objective To enhance brain bioavailability for intranasally administered Eugenol-encapsulated-chitosan-coated-PCL-Nanoparticles (CS-EUG-PCL-NPs).

Methods Chitosan-coated-PCL-Nanoparticles (CS-PCL-NPs) were developed through double emulsification-solvent evaporation technique and further characterized for particle size, zeta potential, size distribution, encapsulation efficiency as well as in vitro drug release. UPLC-PDA method was developed to evaluate brain-drug uptake for optimized CS-EUG-PCL-NPs and to determine it’s pharmacokinetic in rat’s brain as well as plasma.

Results Mean particles size (224.5±5.31), polydispersity index (PDI) i. e. (0.216±0.020) and entrapment efficiency (68.13±5.03) was determined for developed NPs. UPLC-PDA-eλ study showed a significantly high mucoadhesive potential of CS-EUG-PCL-NPs and least for conventional and homogenized nanoformulation; elution time for EUG and internal standard (IS) thymoquinone as 3.50 and 3.61 min were observed respectively. Furthermore, intra and inter-assay (%CV) of 0.25–1.57, %accuracy (97.11-99.00%) as well as a linear dynamic range (100.00 ng/mL–2500.0 ng/mL), was observed. Pharmacokinetic studies in Wistar rat brain and plasma exhibited a high AUC0-24 alongwith an amplified Cmax (p**<0.01) as compared to i. v. treated group.

Conclusions Intranasal administration of developed CS-coated-EUG-loaded-PCL-NPs enhanced the drug bioavailability in rat brain and thus preparation of Eugenol-NPs may help treat cerebral ischemia effectively. The toxicity studies performed at the end revealed safe nature of optimized nanoformulation.
Controlled/Living Radical Polymerization of Semifluorinated (Meth)acrylates
Authors: Chen Mao , Gong Honghong , Gu Yu
Published: April 2018

Fluorinated polymers are important materials for applications in many areas. This article summarizes the development of controlled/living radical polymerization (CRP) of semifluorinated (meth)acrylates, and briefly introduces their reaction mechanisms. While the classical CRP such as atom transfer radical polymerization (ATRP), reversible addition-fragmentation chain transfer (RAFT) polymerization and nitroxide-mediated radical polymerization (NMP) have promoted the preparation of semifluorinated polymers with tailor-designed architectures, recent development of photo-CRP has led to unprecedented accuracy and monomer scope. We expect that synthetic advances will facilitate the engineering of advanced fluorinated materials with unique properties.

1 Introduction

2 Atom Transfer Radical Polymerization

3 Reversible Addition-Fragmentation Chain Transfer Polymerization

4 Nitroxide-Mediated Radical Polymerization

5 Photo-CRP Mediated with Metal Complexes

6 Metal-free Photo-CRP

7 Conclusion
Comprehensive Algorithm for Nasal Ala Reconstruction: Utility of the Auricular Composite Graft
Authors: Chen Collin , Patel Ruchin , Chi John
Published: April 2018

Defects of the nasal ala are challenging to reconstruct, given its complex three-dimensional structure. Successful repair of these defects needs to provide aesthetic symmetry and preserve nasal function. A wide variety of reconstructive options have been described for nasal ala defects, ranging from skin grafts to locoregional flaps, and also includes the auricular composite graft. However, there are currently no comprehensive guidelines for nasal ala repair, and the versatile role of the auricular composite graft has not been well defined. In this review, we aim to provide a comprehensive algorithm to guide repair of nasal ala defects. Additionally, we compare our experience using the auricular composite graft with the available literature to better define its utility in nasal ala repair.
Total Knee Arthroplasty versus Osteochondral Allograft: Prevalence and Risk Factors following Tibial Plateau Fractures
Authors: Oladeji Lasun , Dreger Tina , Pratte Eli , Baumann Charles , Stannard James , Volgas David , Rocca Gregory , Crist Brett
Published: April 2018

Orthopaedic surgeons commonly have the misconception that patients with tibial plateau fractures will likely go on to posttraumatic knee arthritis requiring total knee arthroplasty (TKA). In younger patients, osteochondral allograft (OCA) transplantation is an alternative method to address posttraumatic knee arthritis. The purpose of this study was (1) to identify our institutional failure rate following tibial plateau open reduction and internal fixation (ORIF) (failure was defined as conversion to TKA or OCA); (2) to determine if there are patient- or injury-related risk factors predictive of failure; and (3) to characterize differences between patients treated with TKA versus those treated with OCA transplantation. A 10-year retrospective review was conducted to identify patients treated at our institution with a tibial plateau fracture. Patients included in the final analysis were at least 18 years of age with an articular fracture (AO/OTA 41 B/C). The primary outcome was subsequent ipsilateral OCA or TKA. There were 350 patients (359 tibial plateau fractures) with a mean follow-up of 22.3 months (range, 6–133 months) who met inclusion criteria. Twenty-seven fractures (7.5%) were subsequently converted to a TKA or OCA at an average of 3.75 ± 3.1 years following their initial surgery. Patients who consumed tobacco were 2.3 times more likely to require a joint replacement (confidence interval [CI], 1.0–5.2; p = 0.04). Those patients who received an OCAs were significantly younger as compared with their TKA peers, both at time of initial injury (37 vs. 51 years, p = 0.02) and at time of surgery (41 vs. 55 years, p = 0.009). The joint replacement rate in this study is similar to those studies in the published literature that focused solely on the prevalence of conventional TKA. Tobacco is a risk factor for failure following tibial plateau ORIF. Patients who were treated with an OCA were younger at time of injury and failure.
A Model for Clinical Informatics Education for Residents: Addressing an Unmet Need
Authors: Mai Mark , Luo Brooke , Orenstein Evan , Luberti Anthony
Published: April 2018

Opportunities for education in clinical informatics exist throughout the spectrum of formal education extending from high school to postgraduate training. However, physicians in residency represent an underdeveloped source of potential informaticians. Despite the rapid growth of accredited fellowship programs since clinical informatics became a board-eligible subspecialty in 2011, few resident physicians are aware of their role at the intersection of clinical medicine and health information technology or associated opportunities. In an effort to educate and engage residents in clinical informatics, Children's Hospital of Philadelphia has developed a three-pronged model: (1) an elective rotation with hands-on project experience; (2) a longitudinal experience that offers increased exposure and mentorship; and (3) a resident founded and led working group in clinical informatics. We describe resident participation in these initiatives and lessons learned, as well as resident perceptions of how these components have positively influenced informatics knowledge and career choices. Since inception of this model, five residents have pursued the clinical informatics fellowship. This educational model supports resident involvement in hospital-wide informatics efforts with tangible projects and promotes wider engagement through educational opportunities commensurate with the resident's level of interest.
Thromboembolic Reaction Following Wall Puncture in Arterioles and Venules of the Rabbit Mesentery
Authors: oude Egbrink Mirjam G A , Tangelder Geert Jan , Slaaf Dick W , Reneman Robert S
Published: April 2018

The walls of rabbit mesenteric arterioles and venules (diameter 20 to 40 pm) were punctured with glass micropipets (tip diameter 6 to 8 pm). Thromboembolic reactions resulting from this standardized, small mechanical vessel wall injury could be quantified in vivo with the use of intravital video-microscopy. Following induction of the injury thrombus growth started immediately (<0.1 s). Bleeding times were short, on the average less than 2 s, and did not differ between arterioles and venules. The duration of the embolization process was significantly longer in arterioles than in venules (median 101 and 17 s, respectively), and more emboli were produced in arterioles than in venules (median 6 and 1, respectively). Arteriolar thrombi were more effective in plugging the punctured holes than venular thrombi. The differences in thromboembolic reaction between arterioles and venules, as found in the present study, can probably not be explained by fluid dynamic factors.
Fibrinolytic and Haemostatic Responses to Desamino-D-Arginine Vasopressin (DDAVP) Administered by Intravenous and Subcutaneous Routes in Healthy Subjects
Authors: MacGregor I R , Roberts E M , Prowse C V , Broomhead A F , Ozolins M , Litka P
Published: April 2018

DDAVP was administered at 0.4 ug kg−1 by intravenous (i. v.) and subcutaneous (s.c.) routes to 6 healthy subjects in a double blind crossover study. Both study treatments were well tolerated. Flushing occurred after both treatments but was more prominent after i.v. than after s.c. DDAVP. Mild transient local discomfort at the s.c. injection site occurred in 5 of 6 subjects. The mean peak factor VIII (FVIII) response was 369% and 247% of baseline after i.v. and s.c. DDAVP respectively and the maximum increase in FVIII occurred earlier with the i.v. route. Changes in FVIII antigen (FVIII: Ag) and von Willebrand factor antigen (vWF: Ag) were also monitored. Tissue-type plasminogen activator (t-PA) activity measured by a chromogenic assay employing soluble fibrin had a median peak value of 2.9 IU ml−1 at 20 min after i.v. and of 1.9 IU ml−1 at 60 min after s.c. DDAVP. t-PA antigen was a Iso incasiued so that die specific activity uf ciiculaliiig t-PA could be determined. Preinjection median values of 14,650 and 13,700 IU mg−1 increased to peak median values of 236,200 IU mg−1 at 20 min after i.v. and 202,400 IU mg−1 at 60 min after s.c. DDAVP. Plasminogen activator inhibitor (PAI) activity fell following DDAVP and became undetectable in some subjects during the sampling period. The ratio of maximum fibrinolytic response was similar to the ratio of maximum haemostatic responses obtained by two routes of injection. Our results indicate that s.c. DDAVP might successfully replace i.v. DDAVP in several applications such as confirmation of haemostatic or fibrinolytic responsiveness in patient groups; for obtaining FVIII enriched plasma; as well as its obvious potential usefulness in home treatment of haemophilia A and von Willebrand’s disease.
Plasminogen San Antonio: An Abnormal Plasminogen with a More Cathodic Migration, Decreased Activation and Associated Thrombosis
Authors: Liu Ying , Lyons Roger M , McDonagh Jan
Published: April 2018

An abnormal plasminogen (San Antonio) has been isolated from a patient with axillary vein thrombosis. A decreased level of fibrinolytic activity was detected in both plasma and a purified system. The molecular abnormalities were investigated with both functional and immunological tests. Slightly decreased antigen concentration was noted in plasma. By crossed immunoelec-trophoresis, the patient and his two children had a second small arc and the primary arc migrated more eathodically. A distinct isozyme was detected in the abnormal plasminogen. Functionally, this abnormal plasminogen is characterized by failure to enhance maximal conversion to plasmin, especially by plasminogen activators, which are enhanced by fibrin or fibrin degradation products. The proband and his children are heterozygous for this abnormal plasminogen.
An Enzyme-Linked Immunosorbent Assay (ELISA) Used to Study the Cellular Secretion of Endothelial Plasminogen Activator Inhibitor (PAI-1)
Authors: MacGregor I R , Booth N A
Published: April 2018

A two-site sandwich ELISA was developed to measure PAI-1 antigen and utilised a polyclonal antiserum produced against PAI-1 purified from human endothelial cell secretory products. The assay was calibrated against a preparation of pure PAI-1 whose protein concentration had been determined by amino acid analysis and the detection limit was 30 pg PAI-1 ml“3 sample. PAI-1 was detected in primate sera but not in a wide range of nonprimate sera and no cross-reactivity with α2-antiplasmin or antithrombin III was observed.

The ELISA was used to study cellular secretion of PAI-1 which was confirmed as a major secretory protein in human umbilical vein endothelial cells (HUVEC). PAI-1 antigen accumulated in the medium in a linear fashion with time and accounted for ≃10% of total secreted protein. Specific activity of intracellular PAI1 was typically 20-fold greater than that of PAI-1 in 24 h conditioned medium and a t½ for inactivation of secreted PAI-1 of 0.53 h was calculated. Purified endotoxin stimulated the secretion of PAI-1 antigen and raised the intracellular levels in HUVEC cultures showing that the anti-fibrinolytic actions of endotoxin are effected by increasing the rate of synthesis and secretion of PAI-1.
Kongenitales einfaches Hamartom des retinalen Pigmentepithels
Authors: Sturm Veit , Guber Josef , Silva Marcio , Heckmann Jan , Zawinka Claudia
Published: April 2018

Hintergrund Das kongenitale einfache Hamartom des retinalen Pigmentepithels (CSHRPE) ist ein seltener gutartiger Tumor mit charakteristischen klinischen Eigenschaften. Das typische ophthalmoskopische Bild zeigt eine kleine, gut umschriebene, stark pigmentierte Läsion in Foveanähe. Im Unterschied zur viel häufigeren flachen kongenitalen Pigmentepithelhypertrophie ist das CSHRPE erhaben.

Patienten und Methoden Retrospektive Fallserie von 3 Patienten mit CSHRPE. Die klinisch-morphologischen Merkmale werden unter Berücksichtigung verschiedener bildgebender Verfahren demonstriert.

Ergebnisse Bei 2 Patienten zeigte sich als Zufallsbefund eine typische dunkle Läsion im Bereich der Makula. In der optischen Kohärenztomografie (OCT) war diese als noduläre präretinale Hyperreflektivität mit Verschattung der tieferen Strukturen darstellbar. Die Fluoreszenzangiografie zeigte in einem Fall eine charakteristische persistierende Hypofluoreszenz. Der 3. Patient mit einer Visusminderung auf 0,3 zeigte eine charakteristische Veränderung in der Fovea. Die OCT-Untersuchung demonstrierte hier neben der präretinalen Hyperreflektivität auch eine mäßige Störung der Foveaarchitektur. Die eingeleitete Amblyopietherapie führte im Verlauf zu einem geringen Visusanstieg. Die Läsionen blieben bei 2 Patienten im Verlauf stabil (Nachbeobachtungszeitraum 8 – 14 Monate).

Schlussfolgerung CSHRPE werden häufig als Zufallsbefunde entdeckt. Infolge ihres benignen Charakters und der zumeist asymptomatischen Präsentation sind in der Regel nur Verlaufskontrollen angezeigt. Die Läsionen bleiben gewöhnlich unverändert und wachsen nicht. Bei Visusminderung infolge Foveabeteiligung sollte eine Amblyopiebehandlung versucht werden.
Off-Label Use in Rare Diseases: Myasthenia Gravis, Lambert-Eaton Myasthenic Syndrome and Congenital Myasthenic Syndromes
Authors: Janzen Rudolf
Published: April 2018

The off-label use of licensed drugs is widespread, and the risk of adverse events is elevated, especially if the scientific evidence is low. The treatment of rare diseases (<5/10,000) therefore may increase the risk of off-label use. The optimized standard treatment is primarily based on the regulatory decisions of the German Federal Joint Committee. The valid guidelines and the regulations of the German health system are discussed in this article. The criteria for indication and monitoring of off-label use are shown, especially focused on the problem of refractory myasthenia gravis. Escalation of treatment results regularly in off-label use. The arguments within the applicable guidelines should be followed. Some new aspects of the European regulations are likewise discussed.
Inter-Rater Reliability of Cyclotorsion Measurements Using Fundus Photography
Authors: Dysli Muriel , Kanku Madeleine , Traber Ghislaine
Published: April 2018

Background The foveo-papillary angle (FPA) on fundus photographs is the accepted standard for the measurement of ocular cyclotorsion. We assessed the inter-rater reliability of this method in healthy subjects and in patients with trochlear nerve palsies.

Patients and Methods In this methodological study, fundus photographs of healthy subjects and of patients with trochlear nerve palsies were made with a fundus camera (Zeiss Fundus Camera FF 450 plus, Jena, Germany). Three independent observers measured the FPA on the fundus photographs of all subjects in synedra View (synedra View 16, Version 16.0.0.11, Innsbruck, Austria).

Results One hundred and four eyes of 52 subjects (26 healthy controls and 26 patients) were assessed. The mean FPA of the healthy controls was 5.80 degrees (°) [± 0.44 standard error of the mean (SEM)] compared to 11.55° (± 0.80 SEM) for patients with trochlear nerve palsies. The inter-rater reliability of all measured FPAs showed an intraclass correlation coefficient (ICC) of 0.98 (95% CI 0.97 – 0.98).

Conclusions The inter-rater reliability of objective cyclotorsion measurements using fundus photographs was very high.
The Use of Optical Coherence Tomography for the Detection of Early Diabetic Retinopathy
Authors: Somfai Gabor Mark , Gerding Heinrich , DeBuc Delia
Published: April 2018

Diabetic retinopathy (DR) is one of the leading causes of vision loss globally with a severe burden on all societies due to its high treatment and rehabilitation costs. The early diagnosis of DR may provide preventive steps (including retinal laser therapy and tight carbohydrate, blood pressure, and cholesterol control) that could in turn help to avoid progression of the pathology with the resultant vision loss. Optical coherence tomography (OCT) enables the in vivo structural imaging of the retina, providing both qualitative (structure) and quantitative (thickness) information. In the past decades, extensive OCT research has been done in the field of DR. In the present review, we are focusing on those that were aiming at detection of the earliest retinal changes before DR could be diagnosed funduscopically. The latest, widely available technology of spectral-domain (SD-)OCT comes with a fast and reliable retinal imaging, which, together with the most recent developments in image processing and artificial intelligence, holds the promise of developing a quick and efficient, state-of-the-art screening tool for DR.
Investigation of periodically driven systems by x-ray absorption spectroscopy using asynchronous data collection mode
Authors: Singh H. , Donetsky D. , Liu J. , Attenkofer K. , Cheng B. , Trelewicz J. R. , Lubomirsky I. , Stavitski E. , Frenkel A. I.
Published: April 2018

We report the development, testing, and demonstration of a setup for modulation excitation spectroscopy experiments at the Inner Shell Spectroscopy beamline of National Synchrotron Light Source - II. A computer algorithm and dedicated software were developed for asynchronous data processing and analysis. We demonstrate the reconstruction of X-ray absorption spectra for different time points within the modulation pulse using a model system. This setup and the software are intended for a broad range of functional materials which exhibit structural and/or electronic responses to the external stimulation, such as catalysts, energy and battery materials, and electromechanical devices.
Significant improvement in the electrical characteristics of Schottky barrier diodes on molecularly modified Gallium Nitride surfaces
Authors: Garg Manjari , Naik Tejas R. , Pathak C. S. , Nagarajan S. , Rao V. Ramgopal , Singh R.
Published: April 2018

III-Nitride semiconductors face the issue of localized surface states, which causes fermi level pinning and large leakage current at the metal semiconductor interface, thereby degrading the device performance. In this work, we have demonstrated the use of a Self-Assembled Monolayer (SAM) of organic molecules to improve the electrical characteristics of Schottky barrier diodes (SBDs) on n-type Gallium Nitride (n-GaN) epitaxial films. The electrical characteristics of diodes were improved by adsorption of SAM of hydroxyl-phenyl metallated porphyrin organic molecules (Zn-TPPOH) onto the surface of n-GaN. SAM-semiconductor bonding via native oxide on the n-GaN surface was confirmed using X-ray photoelectron spectroscopy measurements. Surface morphology and surface electronic properties were characterized using atomic force microscopy and Kelvin probe force microscopy. Current-voltage characteristics of different metal (Cu, Ni) SBDs on bare n-GaN were compared with those of Cu/Zn-TPPOH/n-GaN and Ni/Zn-TPPOH/n-GaN SBDs. It was found that due to the molecular monolayer, the surface potential of n-GaN was decreased by ∼350 mV. This caused an increase in the Schottky barrier height of Cu and Ni SBDs from 1.13 eV to 1.38 eV and 1.07 eV to 1.22 eV, respectively. In addition to this, the reverse bias leakage current was reduced by 3–4 orders of magnitude for both Cu and Ni SBDs. Such a significant improvement in the electrical performance of the diodes can be very useful for better device functioning.
Plasma-assisted oxide removal from ruthenium-coated EUV optics
Authors: Dolgov A. , Lee C. J. , Bijkerk F. , Abrikosov A. , Krivtsun V. M. , Lopaev D. , Yakushev O. , van Kampen M.
Published: April 2018

An experimental study of oxide reduction at the surface of ruthenium layers on top of multilayer mirrors and thin Ru/Si films is presented. Oxidation and reduction processes were observed under conditions close to those relevant for extreme ultraviolet lithography. The oxidized ruthenium surface was exposed to a low-temperature hydrogen plasma, similar to the plasma induced by extreme ultraviolet radiation. The experiments show that hydrogen ions are the main reducing agent. Furthermore, the addition of hydrogen radicals increases the reduction rate beyond that expected from simple flux calculations. We show that low-temperature hydrogen plasmas can be effective for reducing oxidized top surfaces. Our proof-of-concept experiments show that an in situ, EUV-generated plasma cleaning technology is feasible.
An upper diameter bound for compact Ricci solitons with application to the Hitchin–Thorpe inequality. II
Authors: Tadano Homare
Published: April 2018

In this addendum to the author’s paper [H. Tadano, J. Math. Phys. 58, 023503 (2017)], by using an upper diameter bound for compact shrinking Ricci solitons by Wu [preprint arXiv:1706.07897 (2017)], we shall give a new sufficient condition for compact four-dimensional shrinking Ricci solitons to satisfy the Hitchin–Thorpe inequality. Our new condition sharpens the validity of the Hitchin–Thorpe inequality given by Tadano [J. Math. Phys. 58, 023503 (2017)].
Terahertz radiation generation through the nonlinear interaction of Hermite and Laguerre Gaussian laser beams with collisional plasma: Field profile optimization
Authors: Safari Samaneh , Niknam Ali Reza , Jahangiri Fazel , Jazi Bahram
Published: April 2018

The nonlinear interaction of Hermite-Gaussian and Laguerre-Gaussian (LG) laser beams with a collisional inhomogeneous plasma is studied, and the amplitude of the emitted terahertz (THz) electric field is evaluated. The effects of laser beams and plasma parameters, including the beams width, LG modes, the plasma collision frequency, and the amplitude of density ripple on the evolution of THz electric field amplitude, are examined. It is found that the shape of the generated THz radiation pattern can be tuned by the laser parameters. In addition, the optimum values of the effective parameters for achieving the maximum THz electric field amplitude are proposed. It is shown that a significant enhancement up to 4.5% can be obtained in our scheme, which is much greater than the maximum efficiency obtained for laser beams with the same profiles.
Fragmentation of twisted light in photon–phonon nonlinear propagation
Authors: Zhu Zhi-Han , Chen Peng , Li Hong-Wei , Zhao Bo , Zhou Zhi-Yuan , Hu Wei , Gao Wei , Lu Yan-Qing , Shi Bao-Sen
Published: April 2018

Twisted light, or orbital angular momentum (OAM) carrying light, has been gradually becoming an important subfield of nonlinear optics. Compared with ordinary light, its chiral phase front provides an additional interface for shaping the phase-matching condition of nonlinear interactions and in consequence reveals a feasible way to tailor light's transverse structure. Here, we explore the nonlinear propagation of twisted light during focused stimulated Brillouin scattering (SBS). Unlike ordinary light that will experience a time-reversal nonlinear reflection, OAM carrying light will break up into corresponding petal-like degenerate OAM modes that carry no net OAM, whereas the superposed OAM modes that carry no net OAM, as the input field, are still time–reversed in focused-SBS. This unexpected phenomenon, resulting from a unique OAM selection rule of noise-initiated SBS, gives more insight into the underlying principle of OAM conservation in electromagnetic interactions and provides an approach to shaping light via nonlinear propagation.
Large enhancement of UV luminescence emission of ZnO nanoparticles by coupling excitons with Ag surface plasmons
Authors: Kuiri Probodh K. , Pramanik Subhamay
Published: April 2018

For an emitter based on bandgap emission, defect mediated emission has always been considered as the most important loss. Here, a novel approach which can overcome such emission loss is proposed using films of ZnO nanoparticles (NPs) on Ag NPs embedded in silica. The effects of the size of Ag NPs on the enhancement of ultra-violet (UV) photoluminescence (PL) of ZnO NPs for such a system have been studied. For the ZnO NPs without Ag NPs, two emission bands have been seen: one in the UV region and the other one in the visible region. This UV PL emission intensity has been seen to increase significantly with a drastic reduction of the visible PL emission intensity in the case of the sample containing ZnO NPs on silica embedded Ag NPs. A linear increase in UV emission with increase in the size of Ag NPs has been found. For the largest size of Ag NPs (∼10 nm, considered in the present study), the PL emission enhancement becomes about 4 times higher than that of sample without Ag NPs. The observed enhancement of the UV PL emission was caused by coupling between spontaneous emission in ZnO and surface plasmons of Ag. The larger Ag NPs provided a larger scattering cross section in coupling surface plasmons to light leading to an increase in UV emission. Thus, it is possible to convert the useless defect emission to the useful excitonic emission with a large enhancement factor.
Dynamics of tongue shaped cavity generated during the impact of high-speed microdrops
Authors: Deka Hiranya , Ray Bahni , Biswas Gautam , Dalal Amaresh
Published: April 2018

Tongue shaped cavities are seen during the hydrophobic sphere impact, jet impact, and impact of a train of microdrops on a deep liquid pool. For the multiple microdrops’ impact, the mechanisms, which lead to deep cavity formation and later bubble entrapment inside the liquid pool, are presented here. The investigations are performed in an air–water system at large values of Froude numbers, thus having a negligible effect of gravity. Depending on the train length, the capillary wave generating from each drop impact affects the necking. The temporal variation of the neck radius shows power law behavior. We delineate the distinctive feature of pinch-off of the cavity in terms of the critical length of the train. Pinch-off is observed when the penetration depth of the cavity is more than three times the diameter of the cavity.
A tandem mass spectrometer for crossed-beam irradiation of mass-selected molecular systems by keV atomic ions
Authors: Schwob Lucas , Lalande Mathieu , Chesnel Jean-Yves , Domaracka Alicja , Huber Bernd A. , Maclot Sylvain , Poully Jean-Christophe , Rangama Jimmy , Rousseau Patrick , Vizcaino Violaine , Adoui Lamri , Méry Alain
Published: April 2018

In the present paper, we describe a new home-built crossed-beam apparatus devoted to ion-induced ionization and fragmentation of isolated biologically relevant molecular systems. The biomolecular ions are produced by an electrospray ionization source, mass-over-charge selected, accumulated in a 3D ion trap, and then guided to the extraction region of an orthogonal time-of-flight mass spectrometer. Here, the target molecular ions interact with a keV atomic ion beam produced by an electron cyclotron resonance ion source. Cationic products from the collision are detected on a position sensitive detector and analyzed by time-of-flight mass spectrometry. A detailed description of the operation of the setup is given, and early results from irradiation of a protonated pentapeptide (leucine-enkephalin) by a 7 keV He+ ion beam are presented as a proof-of-principle.
High spin polarization in epitaxial Fe4N thin films using Cr and Ag as buffer layers
Authors: Li Hongshi , Li Xuan , Kim Dongrin , Zhao Gejian , Zhang Delin , Diao Zhitao , Chen Tingyong , Wang Jian-Ping
Published: April 2018

Fe4N thin films with (001) texture were prepared by reactive sputtering on MgO substrates, utilizing either a Cr or Ag buffer layer to facilitate the epitaxial growth. X-ray diffraction, atomic force microscopy, and vibrating sample magnetometry measurements show that the Fe4N thin film grown on the Ag buffer layer is superior to that grown on the Cr buffer layer. The point contact Andreev reflection measurement was then conducted, and the spin polarizations were determined to be 61.1% and 81.3% for Fe4N thin films with Cr and Ag buffer layers, respectively. The 81.3% spin polarization is significantly higher than the ratio reported previously for Fe4N and is comparable with that of state-of-the-art Heusler alloys. This result is in agreement with the theoretical prediction on the discrepancy between the two differently defined spin polarizations for Fe4N. Moreover, our study indicates that an optimized growth process for Fe4N thin films is crucial for achieving a high spin polarization and that true half-metallicity could potentially be realized with Fe4N. The high spin polarization of Fe4N combined with its low fabrication temperature and simple composition makes Fe4N a competitive candidate to be a half-metallic ferromagnet in spintronic devices.