bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Optimal Stimulus Frequency Ratio for Measurement of the Quadratic f
2
–f
1
Distortion Product Otoacoustic Emission in Humans
Authors: Baiduc Rachael R. , Dhar Sumitrajit
Published: June 2018

Purpose

Distortion product otoacoustic emissions (DPOAEs) are a by-product of active cochlear processes that lead to the compressive nonlinearity of healthy ears. The most commonly studied emission is at the frequency 2f
1
–f
2
, but there has been recent interest in using the quadratic distortion product at the frequency f
2
–f
1
to detect cochleopathies including endolymphatic hydrops. Before the DPOAE at f
2
–f
1
can be applied clinically in any capacity, optimal stimulus parameters for its elicitation must be established.

Method

We investigated stimulus parameters for the DPOAEs at f
2
–f
1
and 2f
1
–f
2
in 23 adults with normal hearing. Logarithmically swept tones between approximately 0.6 and 20 kHz (L
1
= L
2
= 70 dB SPL) served as the higher frequency stimulus (f
2
). DPOAEs were measured for 6 f
2
/f
1
ratios: 1.14, 1.18, 1.22, 1.30, 1.32, and 1.36.

Results

Both DPOAEs were consistently measurable. In line with previous investigations, the highest levels of the DPOAE at 2f
1
–f
2
were generated between f
2
/f
1
ratios of 1.14–1.22, with a peak in the level ratio function at 1.22. In contrast, f
2
–f
1
was less influenced by ratio, although the narrowest ratio (1.14) produced slightly higher levels across frequency.

Conclusion

The DPOAE at f
2
–f
1
is measurable in individuals with normal hearing up to f
2
of 20 kHz at narrow f
2
/f
1
ratios. Measurements at additional stimulus levels and in subjects with hearing impairment will be needed before clinical implementation.
FUV line emission, gas kinematics, and discovery of [Fe XXI] λ1354.1 in the sightline toward a filament in M87
Authors: Anderson Michael E. , Sunyaev Rashid
Published: June 2018

We present new Hubble Space Telescope – Cosmic Origins Spectrograph (HST-COS) G130M spectroscopy which we have obtained for a sightline toward a filament projected 1.9 kpc from the nucleus of M87, near the edge of the inner radio lobe to the east of the nucleus. The combination of the sensitivity of COS and the proximity of M87 allows us to study the structure of this filament in unparalleled detail. We propose that the filament is composed of many cold clumps, each surrounded by an FUV-emitting boundary layer, with the filament having a radius rc ~ 10 pc and the clumps filling the cylinder with a low volume filling factor. The observed velocity dispersion in emission lines from the filament results from the random motions of these clumps within the filament. We have measured fluxes and kinematics for emission lines of Lyα, C II λ1335, and N V λ1238, finding vr = 147 ± 2 km s−1, 138 ± 18 km s−1, and 148−16+14 km s−1 relative to M87, and line broadenings σr = 171 ± 2 km s−1, 189−11+12 km s−1, and 128−17+23 km s−1 respectively. We associate these three lines, as well as archival measurements of Hα, C IV λ1549, and He II λ1640, with a multitemperature boundary layer around clumps which are moving with supersonic random motions in the filament. This boundary layer is a significant coolant of the hot gas. We show that the [C II] λ158 μm flux observed by Herschel-PACS from this region implies the existence of a massive cold (T ~ 103 K) component in the filament which contains significantly more mass (M ~ 8000 M⊙ within our r ≈ 100 pc sightline) than the FUV-emitting boundary layer. It has about the same bulk velocity and velocity dispersion as the boundary layer. We also detect [Fe XXI] λ1354 in emission at 4−5σ. This line is emitted from 1 keV (T ≈ 107 K) plasma, and we use it to measure the bulk radial velocity vr = −92−22+34 km s−1 and velocity dispersion σr = 69−27+79 km s−1 of the plasma at this temperature. In contrast to the intermediate-temperature FUV lines, [Fe XXI] is blueshifted relative to M87 and matches the bulk velocity of a nearby filament to the south. We hypothesize that this line arises from the approaching face of the radio bubble expanding through this sightline, while the filament lies on the receding side of the bubble. A byproduct of our observations is the detection of absorption from interstellar gas in our Galaxy, observed in C II λ1335 and Lyα.
Antiproton–nucleus quasi-bound states within the 2009 version of the Paris N̅ N potential
Authors: Hrtánková Jaroslava , Mareš JiřrÍ
Published: June 2018

We studied the p̅ interactions with the nuclear medium within the 2009 version of the Paris N̅ N potential model. We constructed the p̅–nucleus optical potential using the Paris S - and P-wave p̅ N scattering amplitudes and treated their strong energy and density dependence self-consistently. We considereda phenomenological P-wave term as well. We calculated p̅ binding energies and widths of the p̅ bound in various nuclei. The P-wave potential has very small effect on the calculated p̅ binding energies, however, it reduces the corresponding widths noticeably. Moreover, the S -wave potential based on the Paris amplitudes supplemented by a phenomenological P-wave term yields the p̅ binding energies and widths in very good agreement with those obtained within the RMF model consistent with p̅-atom data.
Kaon and Phi Production in Pion-Nucleus Reactions at 1.7 GeV/c
*supported by the DFG cluster of excellence “Origin and Structure of the Universe” and SFB 1258
Authors: Wirth Joana
Published: June 2018

Nuclear reactions, π−+A (A = C;W), at an incident beam momentum
of 1:7 GeV/c were measured with the HADES setup at SIS18/GSI. Detailed investigations of the K+, K− and ϕ production off nuclei are connected to the study of hadron in-medium properties at nuclear saturation density. A contradictory role is played by the ϕ meson since the ϕN absorption cross-section is assumed to be small due to the OZI suppression which is in contrast to experimental observations. We present the analysis method to identify the ϕ meson exploiting the large K+K− branching ratio (≈ 50%). The correction for acceptance and effciency effects of the detector system will be discussed as well.
Onset of η nuclear binding
Authors: Barnea Nir , Bazak Betzalel , Friedman Eliahu , Gal Avraham , Cieplý Aleš , Mareš Jiří , Schäfer Martin
Published: June 2018

Recent studies of η nuclear quasibound states by the Jerusalem-Prague Collaboration are reviewed, focusing on stochastic variational method self consistent calculations of η few-nucleon systems. These calculations suggest that a minimum value Re aηN ≈ 1 fm (0.7 fm) is needed to bind η3He (η4He).
Dynamically generated hadronic states in the K̅N and ηN coupled-channels interactions
Authors: Cieplý Aleš
Published: June 2018

We compare and review the theoretical predictions for the K̅N and ηN elastic amplitudes where sizable variations are found among the considered approaches, especially at subthreshold energies relevant for studies of kaonic atoms and meson-nuclear quasi-bound states. Conditions for an appearance of dynamically generated states in meson-baryon multi-channel interactions are established and discussed for the K̅N and ηN systems.
Luminosity determination for the proton-deuteron reaction using pd → 3Heη channel with WASA-at-COSY detector
Authors: Skurzok Magdalena , Rundel Oleksandr , Khreptak Aleksander , Moskal Paweł
Published: June 2018

In this report one of the methods used for the luminosity determination for the experiment performed by WASA Collaboration to search for 3He-η mesic nuclei is presented. The method is based on the analysis of pd → 3Heη process.
The Muonium Antimatter Gravity Experiment
Authors: Phillips Thomas J.
Published: June 2018

A direct measurement of the gravitational acceleration of antimatter has the potential to show that we live in a “Dirac-Milne” Universe, which could explain cosmological observations without the need for dark matter, dark energy, inflation, or missing antimatter. Such a measurement would also be sensitive to the possible existence of a fifth force. Cooling antimatter to temperatures where gravitational energies are comparable to thermal energies is challenging for most forms of antimatter, which annihilate upon contact with matter. The exception is the antimuon (μ+), which is easily cooled by stopping in cold matter, but the short muon lifetime poses challenges. Positive muons that stop in material will combine with free electrons to form muonium, a neutral leptonic atom with most of its mass derived from the 2nd-generation antimuon. We are developing the Muonium Antimatter Gravity Experiment (MAGE) to measure the gravitational force on muonium using a novel, monoenergetic, low-velocity, horizontal muonium beam directed at an ultra-precise atom interferometer. If successful, MAGE will measure for the first time the gravitational coupling to a 2nd-generation particle in a system whose antimatter-dominated mass is not predominantly strong-interaction binding energy. The novel MAGE beam production approach could also have important applications to other muonium experiments as well as to the measurement ofg– 2.
EDM Experiments at Storage Rings
Authors: Ströher Hans
Published: June 2018

According to our present understanding, the early Universe contained the same amount of matter and anti-matter and, if the Universe had behaved symmetrically as it developed, every particle would have been annihilated by one of its antiparticles. One of the great mysteries in the natural sciences is therefore, why matter dominates over antimatter in the visible Universe. The breaking of the combined chargeconjugation and parity symmetries (CP-violation, CPV) in the Standard Model of particle physics (SM) is insufficient to explain this and further sources of CPV must be sought. These could manifest themselves in electric dipole moments (EDMs) of elementary particles, which occur when the centroids of positive and negative charges are mutually and permanently displaced. An EDM observation would also be an indication for physics beyond the SM. No EDM has been observed so far; after its discovery, investigations on different systems will be required to pin down CPV sources. In this respect the idea to search for EDMs of charged hadrons (i.p. proton and deuteron) in a new class of precision storage rings has recently been put forward. In addition, such searches bear the potential to reach sensitivities of 10-29 e·cm. The EDM measurement principle, the time development of the polarization vector subject to a perpendicular electric field, is simple, but the smallness of the effect makes this an enormously challenging project. A stepwise approach, from R&D for key-technologies towards the holy grail of a double-beam precision storage ring with counter-rotating beams, is needed. The ongoing research of the JEDI Collaboration at the cooler synchrotron COSY of Forschungszentrum Jülich (Germany) provides invaluable information: recent experimental milestones are presented and discussed.
Toward the measurement of the hyperfine structure of muonic hydrogen in the FAMU experiment: Multi-pass cavity optimization for experiments with pulsed sources.
Authors: Bakalov Dimitar , Stoilov Mihail
Published: June 2018

We consider a simplified model of the optical multi-pass cavity that is being currently developed by the FAMU collaboration for the measurement of the hyperfine splitting in the ground state of muonic hydrogen and of the Zemach radius of the proton. The model is focused on the time distribution of the events of laser-stimulated hyperfine transitions in the muonuc atom and may be helpful in the preliminary design of the FAMU experimental set-up and, more generally, in the optimization of multi-pass optical cavities for experiments with pulsed lasers.
Observation of π−K+ and π+K− atoms
Authors: Yazkov Valeriy ,   DIRAC
Published: June 2018

Experiment DIRAC at CERN PS detects 349 ± 62 pairs from π−K+ and π+K− atoms and makes observation of exotic atoms consist of pion and kaon. It allows to measure a difference of S-wave pion-kaon scattering length with isospin 1/2 and 3/2: |a01/2−a03/2|. Values of pion-kaon scattering lengths are predicted in a frame of ChPT and LQCD. Therefore investigation of π−K+ and π+K− atoms gives possibility to check these predictions for simplest hadronhadron system with s-quark.
A novel approach to stochastic input-output modeling
Authors: Kozicka Marta
Published: June 2018

An approach to input-output modeling is proposed in which the inner consumption and the final demand are random. The main aspects of its novelty are: (a) the economy is allowed to be nonproductive with a certain probability ϰ ∈ [0,1); (b) the economy can be open, which means that import of the corresponding commodities is included in the model. In this approach, the production-and-import plan is set to be feasible if the probability of not satisfying the final demand does not exceed a certain value α ∈ (0,1). Then the problem of finding optimal plans consists in minimizing the production and import costs on the set of feasible plans. The solvability of this problem and properties of the solutions are studied and a concrete example of the stochastic input-output model is analyzed.
DEA models for two decision makers with conflicts: the principal-agent problem
Authors: Gu Yuandong , Zhao Linlin , Zha Yong , Liang Liang
Published: June 2018

This paper studies the impact of two decision makers’ interaction with conflicts on the efficiencies of the system. We start with a general principal-agent framework where the principal and the agent make decisions independently and the principal has a contradictive objective to that of the agent. We develop data envelopment analysis (DEA) models in the principal’s and the agent’s perspectives respectively. Non-cooperation between the principal and the agent is discussed to illustrate how one decision maker affects the other and the corresponding efficiency and incentive contract of the system. In addition, cooperation of the two parties is also analyzed to better derive how the performance of the system is influenced by the parties and their interactions as well. Then, this study illustrates the proposed models and effective incentive contracts by applying them to the efficiency evaluations of 22 China listed electric power companies.
Immune and Inflammatory Response in Atopic Elite Endurance Athletes
Authors: Teixeira Renata , dos Santos Leite Gerson , Gorjao Renata , Palmeira Patricia , Santos Cesar , Zambonatto Raquel , de Oliveira Heloisa , Levada Adriana , Fiks Iara , Carvalho Celso
Published: June 2018

The present study aimed to compare the immune and inflammatory responses between atopic (n=20) and non-atopic (n=39) elite endurance athletes. Fifty-nine elite runners and triathletes were assessed for the following measurements: Th1, Th2 and lymphocyte phenotyping and plasma levels of cortisol, chemokines, inflammatory cytokines and specific immunoglobulin E (IgE). Levels of salivary IgA, allergic symptoms and training data were also evaluated. No difference was observed in baseline lymphocyte levels. However, the Th1 lymphocytes of atopic athletes presented a lower response after activation. In contrast to this result, levels of salivary IgA and CXCL9 chemokine were higher in the atopic athletes. It was observed that the volume of training per week was linearly associated with Th1 levels, allergic symptoms and IgE levels. In addition, linear multiple regression analysis demonstrated that the volume of training was the only factor associated with allergic symptoms in atopic athletes (r=0.53; p=0.04). These results suggest that compared to non-atopic athletes, atopic athletes present a reduced Th1 response and higher levels of salivary IgA. Training volume is associated with the immune response and allergic symptoms, which suggests that they may play a role in the atopy in elite endurance athletes.
Incidence of Achilles and Patellar Tendinopathy in Adolescent Elite Athletes
Authors: Cassel Michael , Risch Lucie , Intziegianni Konstantina , Mueller Juliane , Stoll Josefine , Brecht Pia , Mayer Frank
Published: June 2018

The study investigated the incidence of Achilles and patellar tendinopathy in adolescent elite athletes and non-athletic controls. Furthermore, predictive and associated factors for tendinopathy development were analyzed. The prospective study consisted of two measurement days (M1/M2) with an interval of 3.2±0.9 years. 157 athletes (12.1±0.7 years) and 25 controls (13.3±0.6 years) without Achilles/patellar tendinopathy were included at M1. Clinical and ultrasound examinations of both Achilles (AT) and patellar tendons (PT) were performed. Main outcome measures were incidence tendinopathy and structural intratendinous alterations (hypo-/hyperechogenicity, vascularization) at M2 [%]. Incidence of Achilles tendinopathy was 1% in athletes and 0% in controls. Patellar tendinopathy was more frequent in athletes (13%) than in controls (4%). Incidence of intratendinous alterations in ATs was 1-2% in athletes and 0% in controls, whereas in PTs it was 4-6% in both groups (p>0.05). Intratendinous alterations at M2 were associated with patellar tendinopathy in athletes (p≤0.01). Intratendinous alterations at M1, anthropometric data, training amount, sports or sex did not predict tendinopathy development (p>0.05). Incidence of tendinopathy and intratendinous alterations in adolescent athletes is low in ATs and more common in PTs. Development of intratendinous alterations in PT is associated with tendinopathy. However, predictive factors could not be identified.
Exercise Training Plus Sildenafil Treatment: Role on Autonomic and Inflammatory Markers
Authors: Leoni Luis , Fukushima Andre , Rocha Leandro , Feriani Daniele , Júnior Hélio , Gambassi Bruno , Mostarda Cristiano , Maifrino Laura , Rodrigues Bruno
Published: June 2018

The current study aimed to determine the effects of sildenafil-associated aerobic exercise training (ET) on the physical performance, hemodynamic, autonomic and inflammatory parameters of rats. Male Wistar rats were randomly assigned to: sedentary rats placebo-treated (SP); sedentary rats sildenafil-treated (SS); trained rats placebo-treated (TP); and trained rats sildenafil-treated (TS). Sildenafil treatment consisted of 8 weeks of daily oral gavage (1.5 mg/kg), one hour before the session of ET (60–75% of maximal running speed, 5 days/week, for 8 weeks). After ET period, physical capacity, hemodynamic, autonomic and skeletal muscle inflammatory profile were assessed. Chronic sildenafil treatment causes an additional increase of physical capacity in aerobically trained rats. However, these beneficial effects were accompanied by unwanted alterations, as increased of arterial pressure and peripheral sympathetic modulation, as well as exacerbated inflammatory status on skeletal muscle of rats. Taken together, these data suggest the positive and negative effects of sildenafil chronic administration, associated to aerobic ET, at doses used in clinical practice. This report stresses the importance of paying greater attention to the indiscriminate use of this substance in high-performance sports.
Kampo, A Japanese Traditional Medicinal System for Psychiatric Conditions: A Narrative Review
Authors: Tatsumi Laina , Suzuki Takefumi , Yamada Kazuo , Mimura Masaru , Uchida Hiroyuki
Published: June 2018

Introduction Kampo is a Japanese traditional medicinal system and is represented by unity of mind and body. It is originally based upon Chinese traditional medicine but has uniquely developed in Japan.

Methods A narrative review on the use of Kampo for psychiatric conditions is provided.

Results Kampo formula is a combination of several crude ingredients; most derive from natural plants and some from animals and minerals. These Kampo formulae are widely prescribed in almost all medical disciplines, including psychiatry, in Japan; they have been used for various psychiatric disorders such as dementia, schizophrenia spectrum disorders, mood disorders, anxiety disorders, and personality disorders. Kampo is a versatile traditional medicine with a variety of positive effects on mental states with relatively benign side effect profiles. Kampo formulae can be adjunctively combined with or substituted for the Western psychotropic drugs, which will provide more treatment options to patients with psychiatric conditions.

Discussion This review summarizes the current knowledge on Kampo for psychiatric conditions, highlighting a paucity of data and a need for further good-quality evidence on these medications.
Efficient Conversion of Tertiary Propargylamides into Imidazoles via Hydroamination–Cyclization
Authors: Krasavin Mikhail , Safrygin Alexander , Krivosheyeva Elena , Dar’in Dmitry
Published: June 2018

A method to convert tertiary N-propargylamides into 1,2,4-trisubstituted imidazoles using ammonium chloride and zinc triflate as the catalyst is reported. The method is convenient, practical and employs conventional heating. It is also applicable to N-propargyl lactams and tends to populate the so-called ‘lead-like’ chemistry space.
Synthesis of β-Phenethyl Ethers by Base-Catalyzed Alcohol Addition Reactions to Aryl Alkenes
Authors: Bandar Jeffrey , Luo Chaosheng
Published: June 2018

The direct anti-Markovnikov addition of alcohols to styrene derivatives represents a streamlined route to β-phenethyl ethers, a substructure frequently found in pharmaceuticals and other bioactive ­molecules. Here, we discuss how the development of such a reaction can complement and address limitations of current methods for β-phenethyl ether synthesis. In particular, we highlight our recent ­approach toward achieving this challenging alcohol addition reaction through P4-t-Bu superbase catalysis. A summary of compatible aryl alkenes and alcohols is provided to inform readers of potential applications of this new catalytic transformation, as well as its current limitations and future directions.

1 Introduction

2 Anti-Markovnikov Alcohol Addition to Aryl Alkenes: Background

3 Superbase-Catalyzed Alcohol Addition to Aryl Alkenes

4 Summary and Outlook
Veränderungen des hämostatischen Systems bei drohendem Herzinfarkt
Authors: van de Loo J.
Published: June 2018

V. Zusammenfassung und Ausblick

Zielsetzung von Untersuchungen des hämostatischen Systems in der Situation des drohenden Infarkts kann der Versuch sein, Störungen oder Befundkonstellationen zu finden, die die Pathogenese vor Entstehung eines Herzinfarkts beleuchten. Nach den vorliegenden pathologisch-anatomischen und koronarographischen Befunden ist die Konstellation einer Thrombosetendenz, einer arteriellen Thrombophilie zu erwarten. Denkbar wären in dieser dem Infarkt unmittelbar vorangehenden Phase der instabilen Angina auch Zeichen der aktivierten plasmatischen Gerinnung, einer Aktivierung des thrombozytären Systems und in Analogie zu Zuständen venöser Thrombophilie auch eine Depression des fibrinolytischen Potentials des Blutes. Nur diskrete Zeichen einer Aktivierung des thrombozytären Systems wurden bislang nachgewiesen. Die anderen beiden Systeme sind zu unvollständig untersucht, als daß eine Schlußfolgerung erlaubt ist. Insbesondere fehlen umfassende und gleichzeitige Untersuchungen aller Parameter des hämostatischen Systems am selben Patienten, um das Ineinanderspiel von Aktivierung und Inhibition, von primärer Reaktion und Folgezustand richtig beurteilen zu können.

Derartige Untersuchungen sind jedoch aus folgenden Gründen von besonderer Bedeutung: Auch wenn die Rolle einer thrombotischen Katastrophe bei der koronaren Herzkrankheit weitgehend klar ist, fehlen Informationen, welchem Teilsystem die auslösende Rolle zukommt. Aus der Erforschung dieser Frage könnte sich eine rationale Basis für die medikamentöse antithrombotische Prävention des Erstinfarkts bei Patienten mit stabiler Angina ableiten. Eine große multizentrische europäische Studie bei Patienten mit Angina pectoris und koronarographisch gesicherter stenosierender Koronarsklerose geht dieser Frage im Rahmen der European Concerted Action on Thrombosis and Disabilities (ECAT) nach.

Stellt man die schon heute bekannten Teilkenntnisse über aktivierte Plättchen, die Ergebnisse der Veterans Administration Study von Lewis und Mitarb. und schließlich die relative Ungefährlichkeit der plättchenhemmenden Therapie in Rechnung, halte ich den Versuch einer Behandlung mit Azetylsalizylsäure bei der instabilen Angina pectoris schon heute für begründet. Ob die instabile Angina der sofortigen intravenösen Injektion eines Thrombolytikums bedarf, um die Weiterentwicklung zum transmuralen Infarkt zu unterbrechen, ist noch nicht gesichert, meines Erachtens aber möglich.
Bioartifizielles endokrines Pankreas
Authors: Zekorn T. , Federlin K.
Published: June 2018

Der Diabetes hat einen Anteil von etwa 2 bis 4% in der Bevölkerung von Westeuropa, wobei 20-25% der Patienten Insulin entweder bereits zu Beginn (Typ-I-Diabetes) oder nach Jahren der diätetischen bzw. mit Tabletten durchgeführten Behandlung (Typ-II-Diabetes) benötigen. Obgleich die Einführung des Insulins im Jahre 1922 die Lebenserwartung insbesondere der Typ-I-Diabetiker beträchtlich erweitert hat, sterben nach wie vor ca. 30% an schweren Spätkomplikationen während der Erkrankung. Der Typ-I-Diabetes, insbesondere inzwischen aber auch der Typ II, ist die Hauptursache für Erblindung und Nierenversagen, welches letztlich zur Dialysebehandlung führt bzw. eine Organtransplantation erforderlich macht. Patienten entwickeln darüber hinaus häufig Makro-und Mikroangiopathie sowie Neuropathie, also schwere Veränderungen an den großen und kleinen Blutgefäßen sowie an den peripheren Nerven, aber auch im Bereich des autonomen Nervensystems. Diese Prozesse, die auf verschiedenen pathogenetischen Mechanismen beruhen, insbesondere auf der Glykosylierung von Strukturproteinen mit entsprechender Funktionseinschränkung des Organs sowie auf Schädigungsmechanismen über den Polyol-Stoffwechselweg (osmotische Läsionen im Bereich der Retinakapillaren) , können durch eine nahe nor-moglykämische Diabeteseinstellung verhindert werden. Sie läßt sich tierexperimentell durch Inseltransplantation erreichen. Probleme der Verfügbarkeit von Inseln und der immunologischen Abstoßung führten zu der Vorstellung, einerseits auch tierisches Gewebe einzusetzen (z. B. Schweineinseln) und andererseits das Inselgewebe durch eine semipermeable Membran vor dem Angriff von Lymphozyten und Antikörpern zu schützen (sog. bioartifizielles Pankreas). Verschiedene implantierbare Modelle eines solchen bioartifiziellen Pankreas (BAP) werden beschrieben. Eine Abgrenzung der Inseln vom Blutgefäßsystem und damit vom Immunapparat des Organismus wird durch eine Ma-kroenkapsulation erreicht, andererseits kann auch die einzelne Insel durch eine sogenannte Mikroenkapsu-lation geschützt werden. Die Vor-und Nachteile der einzelnen Methoden werden kurz beschrieben.
Klinische Bedeutung und Bewertung unerwünschter Wirkungen von Biomaterialien - Funktion und Aufgaben eines zentralen Registers
Authors: Bohnerth St , Heinrich W , Wenzel E , Seyfert U. T
Published: June 2018

Verschiedene Gesichtspunkte der Beurteilung und Charakterisierung von Biomaterialien werden dargestellt. Viele Prinzipien, die beim Nachweis unerwünschter Wirkungen von Arzneimitteln gelten, müssen deshalb auch für die Erfassung und Beurteilung unerwünschter Wirkungen beim Einsatz von Biomaterialien Berücksichtigung finden. Die Institutionalisierung eines Zentralen Bioregistes an der Universität des Saarlandes wird vorgestellt. Das Zentrale Bioregister ist ein Spontanerfassungssystem, dessen Effizienz von der Mitwirkung der Ärzte abhängt. Die Effizienz und Rationalität des Einsatzes biokompatibler Materialien kann so sicherlich verbessert werden. So können auch seltene unerwünschte Wirkungen und neue Indikationen erfaßt werden. Es ergeben sich daraus Erweiterungen sowie Einschränkungen einer Therapie mit Biomaterialien.
Das Faktor-XII(Hageman)-Gen des Menschen
Authors: MacGillivray R. T. A , Cool Deborah
Published: June 2018

Es werden die cDNA für den humanen Faktor XII (Hageman-Faktor) und das Gen beschrieben. Die Analyse der vorhergesagten Aminosäuresequenz zeigte, daß die aminoterminale Hälfte des Proteins aus multiplen, dem Fibronektin und Plasminogenaktivator homologen Domänen besteht. Das aus 12 kbp bestehende Gen hat 14 Exone und ist am menschlichen Chromosom 5q33-qter lokalisiert. Zusätzlich wurde ein Taql-Restriktionsfragmentlängen-Polymorphismus (RFLP) beschrieben. Das Modell des Exon shuffling (Exon-Kombination) wurde in dem Befund veranschaulicht, wobei homologe Proteindomänen durch getrennte Exone kodiert werden. Die Intron/Exon-Organisation der Serinproteasedomäne zeigt, daß Faktor XII zur gleichen Subfamilie von Serinproteasen gehört wie die Plasminogenaktivatoren und der Faktor XI.
Zur Pathobiochemie und Pathophysiologie reaktiver Oxidantien bei Ischämie und Reperfusion
Authors: Stief Th. W.
Published: June 2018

Die Letalität des Myokardinfarkts ist heute durch rechtzeitige Verabreichung von Thrombolytika vom Typ der Plasminogenaktivatoren oder Durchführung einer Koronarangioplastie zurückgegangen. Bei der thromboly tischen Behandlung akuter thrombotischer Ereignisse wird allerdings auch der Oxidansphysiologie Rechnung getragen werden müssen, um durch den Einsatz hierauf zielender Therapeutika den Reperfusionsschaden am Gewebe weiter zu begrenzen.

Zur Vermeidung von ReperfusionsSchäden wird zukünftig eine effiziente Fibrinolysetherapie wahrscheinlich eine antientzündliche Begleitkomponente beinhalten. Substanzen mit bislang vermeintlich klarem klinischen Wirkungsprofil, wie Azetylsalizylsäure, Dipyridamol, Captopril, Heparin oder Kalziumantagonisten, könnten durchaus auf diese Weise ihren Teil zur therapeutischen Wirkung bei Ischämie/Reperfusion beitragen.
Fibrinolyse und kardioprotektive Therapie
Authors: Winther K.
Published: June 2018

Nichtselektive ß-Rezeptoren-Blok-kade verlängert die ECLT und vermindert die Aktivität des Gewebe-plasminogenaktivators (3, 4, 7). Selektive ß-Rezeptoren-Blocker verändern die fibrinolytische Aktivität nicht, während Blocker mit ISA entsprechend ihrer ISA-Aktivität die Fibrinolyse beeinflussen. Die Wirkung von Kalziumkanalblockern ist noch nicht ausreichend untersucht. Eine mögliche günstige Wirkung dieser Medikamente auf die fibrinolytische Aktivität bei verschiedenen Gruppen von Patienten kann jedoch nicht ausgeschlossen werden.
Thrombogenese und Hämodynamik
Authors: Wurzinger L. J.
Published: June 2018

Die in enger Kooperation von medizinisch-theoretischen (Anatomie, Physiologie) und ingenieurwissen-schaftlichen (Aerodynamisches Institut) Disziplinen an der RWTH Aachen erarbeiteten Befunde zeigen, daß nur jeweils ein verschwindend kleiner Anteil von Plättchen (und anderen Blutzellen) im alternden bzw. atherosklerotisch vorgeschädigten Kreislauf Bereiche kritischer Strömungskräfte durchläuft, von denen wiederum nur ein geringer Prozentsatz irreversibel geschädigt wird. Obwohl dieses Trauma grundsätzlich einen auslösenden Reiz auf das Hämo-stasesystem darstellt, erfordern die nachgeschalteten zellbiologischen und biochemischen Verstärkerschritte gänzlich andere fluiddynamische Bedingungen, als sie in schneller, ungestörter Rohrströmung gegeben sind. Die Manifestation und Lokalisation des Thrombus scheint von fluiddyna-misch abgeschlossenen Rezirkula-tionsgebieten bestimmt zu sein.
Rekombinanter »tissue-type«-Plasminogenaktivator (rt-PA) bei Lungenembolie Übersicht
Authors: Schmutzler R.
Published: June 2018

Zusammenfassende Beurteilung aller Studien

Die Dauer der Infusion und die Konzentration der Plasminogenakti-vatoren. spielt für die Sicherheit der Patienten eine große Rolle. Eine höhere Konzentration in kurzer Zeit ist bei der LE anscheinend das bessere, d.h. effektivere Dosierungsprogramm. Sollte jedoch nach 2 Stunden im Kontroll-Angiogramm noch kein genügender Lyseeffekt sichtbar sein, so kann die Lysebehandlung – wie die Studien zeigen – mit einer etwas geringeren Dosis auf 6 bis 7 Stunden verlängert werden.

Der Vergleich zwischen intravenöser und intrapulmonaler rt-PA-Appli-kation erbrachte bei gleicher Dosierung den gleichen thrombolytischen Effekt. Dies ist insofern interessant und überraschend, da nach bisheriger Anschauung die direkte thrombusnahe Verabreichung durch den Pulmo-nalarterienkatheter als effektiver galt.

Die Urokinase ist in der hier vorliegenden Studie im Vergleich zu rt-PA aus heutiger Sicht ganz offensichtlich zu gering dosiert und somit weniger aggressiv. Daher hat nach 2 Stunden rt-PA den größeren Vorteil bei den angegebenen Dosierungen. Nach 24 Stunden gleicht sich der Endpunkteffekt offenbar an.

In Zukunft sollten vergleichende Studien durchgeführt werden, wobei gleiche Dosierungen zu gleichen Zeitpunkten den erwirkten Effekt kontrollieren. Für Langzeitkontrollen sind Tod und wiederholte LE die wichtigsten Parameter, die möglicherweise Rückschlüsse auf die Art der Initialbehandlung vermitteln.
Plättchenfunktionshemmer neue pharmakologische Ansätze
Authors: Schrör K.
Published: June 2018

Ziel der klinischen Therapie mit Thrombozytenfunktionshemmern ist eine Verhinderung von thrombotischen Gefäßverschlüssen bei bestehendem erhöhten vaskulären Risiko. Aufgrund der Physiologie der Plättchenaktivierung eignen sich hierfür besonders solche Pharmaka, die mit rezeptorgekoppelten zellulären Transduktionsmechanismen interferieren. Azetylsalizylsäure (ASS) als Referenzsubstanz hat den Vorteil einer irreversiblen Hemmung der Plättchensekretion und guter Verträglichkeit bei niedriger Dosierung (<100 mg/d), die offenbar für die Prävention des Herzinfarkts ausreicht. Thromboxansynthesehemmer wirken im Gegensatz zu ASS nicht negativ auf die vaskuläre Prostazyklinsynthese, waren aber in der Klinik bisher ASS nicht überlegen. Thromboxanrezeptorenblocker führen zu einer kombinierten Hemmung von Plättchensekretion und thromboxanmediierten Gefäßspasmen. Neuere oral wirksame Substanzen (GR 32.191; Bay U 3405) scheinen einen Langzeiteffekt zu besitzen. Von erheblichem Interesse sind monoklonale Antikörper gegen den GP-llb/llla-Komplex sowie Hirudin und Ticlopidin.
Applikation von Fibrinogen und Fibrin bei Störungen der primären Wundheilung
Authors: Claus G. , Köstering H. , Wieding J. U.
Published: June 2018

Bei Patienten mit Störung der primären Wundheilung nach operativen Eingriffen oder im Rahmen anderer Erkrankungen, z.T. mit Störung der Mikrozirkulation, erfolgte die Applikation von Fibrinogen/Fibrin zur Förderung der Wundheilung. Neben der üblichen oberflächlichen Applikation im Sinne eines plastischen Wundverschlusses wurde zur Steigerung der proliferativen Prozesse gezielt das Fibrinogen (ohne Thrombin!) auch flach in den Wundgrund injiziert.

Insgesamt war bei Patienten mit Fibrin(ogen)-Applikation eine Verkürzung der Heilungsdauer festzustellen, die wiederum von vorbestehenden Mikrozirkulationsverhältnissen abhing; Wundinfektionen nahmen ab, Abszeßbildung trat nicht auf.

Die beschleunigte Wundheilung wird u.a. auf die Steigerung proliferativer Prozesse zurückgeführt.

Bei Störungen der primären Wundheilung unterschiedlicher Genese, selbst bei vorbestehender Wundinfektion, erscheint daher die Applikation von Fibrinogen/Fibrin sinnvoll.
PRUNE1 Deficiency: Expanding the Clinical and Genetic Spectrum
Authors: Schossig Anna , Haack Tobias , Kovács-Nagy Reka , Braunisch Matthias , Makowski Christine , Senderek Jan , Vill Katharina , Müller-Felber Wolfgang , Strom Tim , Krabichler Birgit , Freisinger Peter , Deshpande Charu , Polster Tilman , Wolf Nicole , Desguerre Isabelle , Wörmann Friedrich , Rötig Agnès , Ahting Uwe , Kopajtich Robert , Prokisch Holger , Meitinger Thomas , Feichtinger René , Mayr Johannes , Jungbluth Heinz , Hubmann Michael , Zschocke Johannes , Distelmaier Felix , Koch Johannes , Alhaddad Bader
Published: June 2018

Background Primary microcephaly and profound global developmental delay have been considered the core clinical phenotype in patients with bi-allelic PRUNE1 mutations.

Methods Linkage analysis and whole-exome sequencing (WES) in a multiplex family and extraction of further cases from a WES repository containing 571 children with severe developmental disabilities and neurologic symptoms.

Results We identified bi-allelic PRUNE1 mutations in twelve children from six unrelated families. All patients who survived beyond the first 6 months of life had early-onset global developmental delay, bilateral spastic paresis, dysphagia and difficult-to-treat seizures, while congenital or later-evolving microcephaly was not a consistent finding. Brain MRI showed variable anomalies with progressive cerebral and cerebellar atrophies and T2-hyperintense brain stem lesions. Peripheral neuropathy was documented in five cases. Disease course was progressive in all patients and eight children died in the first or early second decade of life. In addition to the previously reported missense mutation p.(Asp106Asn), we observed a novel homozygous missense variant p.(Leu172Pro) and a homozygous contiguous gene deletion encompassing most of the PRUNE1 gene and part of the neighboring BNIPL gene.

Conclusions PRUNE1 deficiency causes severe early-onset disease affecting the central and peripheral nervous systems. Microcephaly is probably not a universal feature.
Nucleation limited switching (NLS) model for HfO2-based metal-ferroelectric-metal (MFM) capacitors: Switching kinetics and retention characteristics
Authors: Gong N. , Sun X. , Jiang H. , Chang-Liao K. S. , Xia Q. , Ma T. P.
Published: June 2018

HfO2-based ferroelectrics (FE-HfO2) have shown promise as an emerging 1-T (single-transistor) non-volatile memory candidate because of its attractive features, such as CMOS compatibility, scalability, fast switching speed, low power, and long retention. The nucleation limited switching (NLS) model, which attributes the polarization switching mainly to the waiting time of nucleation of reversed domains, has been well developed to interpret experimental results for both ferroelectric switching and retention of metal-ferroelectric-metal (MFM) devices based on conventional perovskite ferroelectric materials [such as Pb(Zr, Ti)O3]. However, the applicability of this model to HfO2-based MFM capacitors is not well understood, although some recent experimental evidence has suggested so. In this study, we thoroughly investigated the switching kinetics and the retention characteristics of FE-HfO2 in the context of the NLS model. We show that (1) the NLS model agrees well with the experimental results of switching kinetics over 5 orders of pulse widths, and the extracted modeling parameters are also consistent with those predicted by the density-functional-theory analysis, indicating that the nucleation of reversed domain indeed dominates the switching speed and (2) the NLS model also agrees well with the experimental retention characteristics of HfO2-based MFM devices both at room temperature and at 85 °C.
Electro-thermally driven transport of a non-conducting fluid in a two-layer system for MEMS and biomedical applications
Authors: Kunti Golak , Dhar Jayabrata , Bhattacharya Anandaroop , Chakraborty Suman
Published: June 2018

Biomedical and biochemical applications pertaining to ion exchange or solvent extraction from one phase to another phase often deal with two-fluid flows, where one layer is non-conducting and the other layer is a biofluid. In the present study, we investigate the transport of two-layer immiscible fluids consisting of one non-conducting fluid and another conducting fluid layer in a micro-grooved channel, employing an alternating current electrothermal (ACET) mechanism. The conducting fluid, driven by the influence of ACET forces, transfers its induced momentum across the fluid-fluid interface allowing the movement of the non-conducting fluid layer. We use an order parameter based approach to track the interface of the two-layer fluid transport via the coupled Cahn-Hilliard-Navier-Stokes equation, while the potential and temperature distribution are solved using the Laplace equation and the thermal energy balance equation, respectively. The efficiency with which the non-conducting layer gets transported is studied with respect to various parameters. We find that the transport mechanism with the ACET process has striking advantages over the contemporary electrically actuated flow.
Perspective: Towards understanding the multiscale description of cells and tissues by electromechanobiology
Authors: Shamoon D. , Lasquellec S. , Brosseau C.
Published: June 2018

Almost all biological cells in living tissues exert and experience forces that influence biological function. When subjected to an exogenous electric field, mechanical forces operate on cells, its constituents, and interfaces with the environment. Many issues about force generation and dynamics, the distance over which a force exerts its influence and how cells convert an electrical excitation into a mechanical deformation, are not well understood from general first-principles physics. The electric field at the interface between cells is not only the driving force for the polarization and conduction phenomena but also induces simultaneously a mechanical stress field. Within the extremely heterogeneous multicellular structure of biological materials (BM), theoretical models and experimental techniques to understand and control their local electromechanical response in BM grow space. In recent years, biophysicists have begun to uncover the important time and length scales that mediate force propagation in BM. In this perspective review, the multiscale modelling approaches and experimental probes for the application of an electromagnetic field to exert mechanical forces upon polarizable BM are reported with special emphasis on the control of forces at the cell and tissue levels. Modelling is based on a multicellular assembly exchanging charges and stresses with the environment. Here, we shall restrict to coarse-graining models since the resulting computational complexity quickly becomes overwhelming. Such work can pave the way for a deeper understanding of how physical forces influence biological functions.
Investigations on the structural, multiferroic, and magnetoelectric properties of Ba1-xCexTiO3 particles
Authors: Senthilkumar P. , Dhanuskodi S. , Muneeswaran M. , Giridharan N. V. , Kuila S. , Vishwakarma P. N.
Published: June 2018

The present study reports the synthesis of Ba1-xCexTiO3 (x = 0, 1, 2, 3, and 4 mol. %) particles by the sol-gel method and investigates the ferroelectric and magnetoelectric coupling properties. Rietveld refinement of XRD analysis identifies the structural transformation from tetragonal to pseudocubic above 2 mol. % of Ce concentration supported by Raman spectra. The unitcell volume V has increased due to the substitution of Ce3+ and Ce4+ ions on both Ba and Ti sites. XPS data reveal that the oxygen vacancies are rich for Ce doped BaTiO3 compared to the undoped particles. From the FESEM analysis, a gradual increase in the average grain size from 618 to 1046 nm is found up to 3 mol. % and then decreases for 4 mol. % (537 nm). The PE loop determines the highest Pr value of 9.95 μC/cm2 at 2 mol. % of Ce due to the existence of the morphotropic phase boundary (tetragonal + pseudocubic phases). MH curves show that the net magnetization enhances from 6.63 to 7.9 × 10−4 emu/g on Ce doping. Further, the dynamic magnetoelectric measurement demonstrates that the coefficients α and β are maximum at 2 mol. % of Ce ions owing to the strain mediated magnetoelectric coupling.
The viscosity of charged particles in the weakly ionized plasma with power-law distributions
Authors: Wang Yue , Du Jiulin
Published: June 2018

We study the viscosity of light charged particles in weakly ionized plasma with the power-law q-distributions using the generalized Boltzmann equation of transport and the motion equation of hydrodynamics. The nonequilibrium plasma variables are considered to be space inhomogeneous and without magnetic field. We derive the expressions of the viscosity coefficients of electrons and ions in the q-distributed plasma, including the first and the second viscosity coefficients. It is shown that these new viscosity coefficients depend strongly on the q-parameters, and when we take q → 1, they perfectly return to those in the plasma with a Maxwellian distribution. The discussions presented in this paper can also be applied to the plasmas with the kappa-distributions.
Electric control of cooperative polariton dynamics in a cavity-magnon system
Authors: Rao J. W. , Yao B. M. , Fan X. L. , Xue D. S. , Gui Y. S. , Hu C.-M.
Published: June 2018

The recent development of cooperative magnon-polariton dynamics in feedback coupled cavities holds great potential for non-classical information processing. With the goal of increasing the cooperativity and integrating this innovative technique with microwave circuits, in this paper, we have developed a tunable, planar, feedback-coupled cavity consisting of an active cavity and a varactor-loaded passive cavity. By tuning the voltage bias, the feedback cavity can operate in a wide frequency range with a quality factor better than 104. As a consequence, our feedback cavity allows both the magnetic control and electric control of the coherent magnon-photon dynamics, enabling the controllable evolution of a cavity-magnon triplet to a cavity-magnon quintuplet. This electric control of the coherent magnon-photon dynamics may enable the design of on-chip polariton devices which exploit electromagnetic wave-matter interactions.
Integration of fiber Bragg grating temperature sensors in plasma facing components of the WEST tokamak
Authors: Corre Y. , Laffont G. , Pocheau C. , Cotillard R. , Gaspar J. , Roussel N. , Firdaouss M. , Gardarein J.-L. , Guilhem D. , Missirlian M.
Published: June 2018

Plasma Facing Components (PFC) temperature measurement is mandatory to ensure safe high power and long pulse tokamak operation. IR thermography systems which are widely used in magnetic fusions devices become challenged with the choice of tungsten as a PFC material in the ITER tokamak, mainly due to emissivity uncertainties and reflection issues in a hot environment. Embedded temperature measurements are foreseen to cross-check the IR thermography measurements. Fiber Bragg grating sensors are potentially of great interest for this application because they are immune to electromagnetic interference and allow the measurement of a large number of temperature spots on a single fiber. Four optical fiber temperature sensing probes, each of them including 11 regenerated fiber Bragg gratings equally spaced by 12.5 mm (equivalent to one ITER-like tungsten monoblock), have been specifically designed and manufactured for the WEST project (W-tungsten Environment and Steady State Tokamak). The four probes are embedded in W-coated graphite components at two different distances from the surface, 3.5 mm and 7 mm, to cover a wide range of temperatures up to 900 °C. This paper addresses the design and integration issues and the qualification and performance assessment performed in the laboratory. It also shows the first measurements of this new diagnostic achieved in a tokamak environment during baking of the machine and during early diverted plasma exposure.
Chaotic laser voltage: An electronic entropy source
Authors: Wishon Michael J. , Li Nianqiang , Choi D. , Citrin D. S. , Locquet Alexandre
Published: June 2018

The chaotic terminal voltage dynamics of a semiconductor laser subjected to external optical feedback are utilized to directly generate electronic random number streams with minimal post-processing at rates of 40–120 Gb/s, thus obviating the need for optical-to-electrical conversion and facilitating integration with high-speed computers and devices. Furthermore, a comparison of the terminal voltage to the optical intensity being utilized as entropy sources is performed. It is shown that the voltage dynamics have an inherently larger entropy, a reduction in delay signature, and a more suitable distribution for generating random bit streams.