bluuebunny/crossref_metadata_2025 huggingface dataset:
Weld formation during material extrusion additive manufacturing
Authors: Seppala Jonathan E. , Hoon Han Seung , Hillgartner Kaitlyn E. , Davis Chelsea S. , Migler Kalman B.
Published: August 2017

A combination of thermography, rheology, and fracture mechanics captures weld formation during the material extrusion process.
Spontaneous emulsification and self-propulsion of oil droplets induced by the synthesis of amino acid-based surfactants
Authors: Nagasaka Yuriko , Tanaka Shinpei , Nehira Tatsuo , Amimoto Tomoko
Published: August 2017

It is well known that oil droplets in or on water exhibit spontaneous movement induced by surfactants, and this self-propulsion is regarded as an important factor in droplet-based models for a living cell.
Kinetics in directional drying of water that contains deformable non-volatile oil droplets
Authors: Hasegawa K. , Inasawa S.
Published: August 2017

Packing of deformable oil droplets severely retards drying of water, which is well described by a mathematical model.
Visualizing molecular distributions for biomaterials applications with mass spectrometry imaging: a review
Authors: Paine Martin R. L. , Kooijman Pieter C. , Fisher Gregory L. , Heeren Ron M. A. , Fernández Facundo M. , Ellis Shane R.
Published: August 2017

A review highlighting current trends, key applications, and the vast potential of mass spectrometry imaging for biomaterials research.
The role of vascular endothelial growth factor-B in metabolic homoeostasis: current evidence
Authors: Zafar  Mohammad Ishraq , Zheng Juan , Kong Wen , Ye Xiaofeng , Gou Luoning , Regmi Anita , Chen Lu-Lu
Published: August 2017

It has been shown that adipose tissue and skeletal muscles in lean individuals respond to meal-induced hyperinsulinemia by increase in perfusion, the effect not observed in patients with metabolic syndrome. In conditions of hyperglycaemia and hypertriglyceridemia, this insufficient vascularization leads to the liberation of reactive oxygen species (ROS), and disruption of nitric oxide (NO) synthesis and endothelial signalling responsible for the uptake of circulating fatty acids (FAs), whose accumulation in skeletal muscles and adipose tissue is widely associated with the impairment of insulin signalling. While the angiogenic role of VEGF-A and its increased circulating concentrations in obesity have been widely confirmed, the data related to the metabolic role of VEGF-B are diverse. However, recent discoveries indicate that this growth factor may be a promising therapeutic agent in patients with metabolic syndrome. Preclinical studies agree over two crucial metabolic effects of VEGF-B: (i) regulation of FAs uptake and (ii) regulation of tissue perfusion via activation of VEGF-A/vascular endothelial growth factor receptor (VEGFR) 2 (VEGFR2) pathway. While in some preclinical high-fat diet studies, VEGF-B overexpression reverted glucose intolerance and stimulated fat burning, in others it further promoted accumulation of lipids and lipotoxicity. Data from clinical studies point out the changes in circulating or tissue expression levels of VEGF-B in obese compared with lean patients. Potentially beneficial effects of VEGF-B, achieved through enhanced blood flow (increased availability of insulin and glucose uptake in target organs) and decreased FAs uptake (prevention of lipotoxicity and improved insulin signalling), and its safety for clinical use, remain to be clarified through future translational research.
21.3 dBm 18.5 GHz‐BW 8‐way E‐band power amplifier in 28 nm high performance mobile CMOS
Authors: Zhao Dixian , Reynaert Patrick
Published: August 2017

A fully integrated broadband E‐band power amplifier (PA) is implemented in 28 nm CMOS process. To enhance the output power (POUT), an 8‐way differential series‐parallel power combiner is used together with the neutralised bootstrapped cascode amplifier topology. The unit PAs are realised by both NMOS and PMOS transistors, respectively, which cancel the amplitude‐to‐phase modulation (AM‐PM) distortion due to non‐linear gate‐to‐source capacitance (CGS) of NMOS and PMOS transistors under large input voltage amplitude. The presented PA achieves a saturated output power (PSAT) of 21.3 dBm with more than 18.5 GHz −3 dB small‐signal bandwidth (BW−3 dB).
Improved deep face identification with multi‐class pairwise discriminant loss
Authors: Choi J.Y.
Published: August 2017

A novel method to extract discriminative deep feature representations of facial images for face identification is presented. A new ‘multi‐class pairwise discriminant loss’ is devised and incorporated it into the general deep convolutional neural network learning framework in a novel way, leading to highly discriminative deep face features. The method shows significant improvement over existing deep feature extraction techniques relying on softmax or triplet loss. Moreover, the method achieves a level of accuracy on the widely used identification protocols, which are better and comparable results than other state‐of‐the‐art methods.
Dielectric characterisation of small samples using broadband coaxial cavity
Authors: Yu Chengyong , Li En , Guo Gaofeng
Published: August 2017

A method aimed at dielectric parameters measurement of small samples using a coaxial re‐entrant cavity is proposed. After introducing grooves in the cavity structure to suppress parasitic modes, the operating frequency range has been broadened to 0.6–13 GHz for only one cavity. Compared to the traditional structure, the working bandwidth has expanded to 344% of the original one. The cavity perturbation technique is applied to detect the complex permittivity. The proposed method features two advantages over existing techniques, high sensitivity and more convenience for placing the sample.
A low‐complexity demodulation technique for spectrally efficient FDM systems using decision‐feedback
Authors: Yu Baoxian , Zhang Han , Dai Xianhua
Published: August 2017

Spectrally efficient frequency division multiplexing enables higher spectral efficiency at the cost of suffering from inter‐carrier interference (ICI), which leads to either a severe error floor or a heavy computational burden at the receiver. In this study, the authors propose a low‐complexity demodulation technique, in which the detected symbols are used as feedback to effectively mitigate ICI. To restrain the error propagation caused by non‐ideal feedback, the authors enumerate subsequent unknown symbols as preconditions, and then perform the demodulation based on minimum distance criterion, in order to enable the optimal solution in each step of feedback. As a consequence, the computations necessitated to data demodulation can be significantly reduced as a quadratic order of symbol‐size. Furthermore, the authors mathematically characterise the demodulation performance by deriving the signal‐to‐interference‐plus‐noise ratio as a function of bandwidth compression factor. It is shown that the demodulation scheme can effectively reduce the error floor raised by ICI while preserving a low complexity. Simulation results demonstrate that the proposed demodulator outperforms the conventional ones, and achieves indistinguishable performance as that of orthogonal frequency‐division multiplexing while increasing up to 25% spectrum efficiency.
Quadrature spatial media‐based modulation with RF mirrors
Authors: Pillay Narushan , Xu HongJun
Published: August 2017

The use of radio frequency (RF) mirrors to improve spectral efficiency is a recently introduced technique. The authors investigate its application to single RF chain and inter‐channel interference‐free communications. The technique is first applied to improve the error performance of a conventional single‐input multiple‐output (SIMO) scheme, in the form of SIMO media‐based modulation (SIMO‐MBM) with single‐mirror activation pattern (MAP). Significant improvement in error performance is demonstrated. The theoretical average bit error probability (ABEP) of SIMO‐MBM with single MAP is formulated and serves to validate the Monte‐Carlo simulation results. The application of RF mirrors to further improve spectral efficiency in quadrature spatial modulation is then proposed, in the form of quadrature spatial media‐based modulation (QSMBM) and is able to achieve very large spectral efficiencies, while maintaining relatively good error performance. The theoretical ABEP of QSMBM is formulated and shown to agree well with Monte‐Carlo simulation results. Finally, MAP selection for QSMBM is investigated. Due to the high computational complexity and memory requirements of optimal MAP selection, low‐complexity suboptimal algorithms for MAP selection are investigated. A significant improvement in the error performance of QSMBM is demonstrated with these algorithms.
OFDM for payload communications of UAS: channel estimation and ICI mitigation
Authors: Vahidi Vahid , Saberinia Ebrahim
Published: August 2017

For real‐time transmission of high‐bandwidth sensor data from an unmanned aircraft vehicle (UAV) to the ground station (GS) in an unmanned aircraft system, a high‐speed payload communication system is essential. While orthogonal frequency‐division multiplexing (OFDM) is very effective for terrestrial wideband systems, possible higher speed of UAVs or higher carrier frequencies can increase the Doppler shift, and therefore increase the inter‐carrier interference (ICI) in OFDM systems. In these scenarios, the complete frequency‐domain channel matrix should be estimated and used for ICI mitigation and data recovery. In this study, a time‐domain pilot‐based channel estimation scheme is described to estimate the entire frequency‐domain channel matrix for moderate‐to‐high Doppler OFDM systems. Simulation results indicate that the new scheme provides better performance compared with channel estimation schemes designed for low Doppler scenarios that partially estimate the frequency‐domain channel matrix. The comparison is also presented with the other full channel estimation scheme, named autoregressive scheme, showing a comparable performance with much lower complexity for the new scheme.
Discriminative feature learning‐based pixel difference representation for facial expression recognition
Authors: Sun Zhe , Hu Zheng‐Ping , Wang Meng , Zhao Shu‐Huan
Published: August 2017

Recently, researchers have proposed different feature descriptors to achieve robust performance for facial expression recognition (FER). However, finding a discriminative feature descriptor remains one of the critical tasks. In this paper, we propose a discriminative feature learning scheme to improve the representation power of expressions. First, we obtain a discriminative feature matrix (DFM) based pixel difference representation. Subsequently, all DFMs corresponding to the training samples are used to construct a discriminative feature dictionary (DFD). Next, DFD is projected on a vertical two‐dimensional linear discriminant analysis in direction (V‐2DLDA) space to compute between and within‐class scatter because V‐2DLDA works well with the DFD in matrix representation and achieves good efficiency. Finally, nearest neighbor (NN) classifier is used to determine the labels of the query samples. DFD represents the local feature changes that are robust to the expression, illumination et al. Besides, we exploit V‐2DLDA to find an optimal projection matrix since it not only protects the discriminative features but reduces the dimensions. The proposed method achieves satisfying recognition results, reaching accuracy rates as high as 91.87% on CK+ database, 82.24% on KDEF database, and 78.94% on CMU Multi‐PIE database in the LOSO scenario, which perform better than other comparison methods.
A new strategy based on hybrid battery–wind power system for wind power dispatching
Authors: Gholami Mehrdad , Fathi Seyed Hamid , Milimonfared Jafar , Chen Zhe , Deng Fujin
Published: August 2017

Battery energy storage system (BESS) is one of the best solutions to compensate the wind power fluctuations and forecasting errors for participation in the power markets by contribution in the energy production several hours ahead. Based on coordination of BESS and wind power, this study aims to present a new strategy to optimise the BESS size and increase the battery lifetime. In the proposed strategy, the average wind power is considered as the dispatch power to minimise the battery capacity and two back up battery sets are utilised to avoid shallow charge–discharge cycles for saving the battery efficiency and lifetime. In addition, the short‐term operation criterion is chosen to deal with the prediction error effects. The proposed method is applied to a 2 MW wind turbine as a case study with 2 years wind data. Simulation results show the effectiveness of the proposed strategy.
Load frequency control of power systems with non‐linearities
Authors: Tan Wen , Chang Shuaibing , Zhou Rong
Published: August 2017

Load frequency control (LFC) for power systems with governor deadband (GDB) and generation rate constraint (GRC) non‐linearities is discussed in this study, with the objective to add anti‐windup schemes for any designed LFC controller, so that the stability and performance of the existing LFC controller can be retained when there are non‐linearities. Effects of GDB and GRC on the performance of LFC controllers are first analysed via describing function method. Anti‐windup schemes are then proposed to compensate the GDB and GRC non‐linearities. For GDB, the error between the realistic and the ideal outputs of the generator is added to the output of LFC controller for rejection, and for GRC, the error between the realistic and the ideal outputs of the turbine is fed back to the observer of the LFC controller for estimation and elimination. Simulation results show that the compensation schemes are effective in overcoming the adverse effects of GDB and GRC.
Accelerated switching function model of hybrid MMCs for HVDC system simulation
Authors: Li Rui , Xu Lie , Guo Deyang
Published: August 2017

An accelerated switching function model (SFM) of the hybrid modular multilevel converter comprising both full‐bridge (FB) and half‐bridge (HB) submodules (SMs) in each arm is presented for HVDC system simulation, where auxiliary circuits are adopted to represent all possible current paths during normal and fault conditions. The proposed SFM can represent the negative voltage generating capability of the FB SMs and the equivalent switching functions in the blocking states of the FB and HB SMs are also introduced in the proposed model to accurately replicate the potential charging of the SM capacitors, yielding improved simulation accuracy compared to other alternatives. In addition to the faster simulation speed, the proposed model accurately reproduces the converter behaviour during various operating conditions, including normal operation, AC fault, DC fault and so on. The proposed SFMs are assessed in MATLAB/Simulink environment using both down‐ and full‐scale HVDC links and the simulation results confirm the validity of the proposed model in terms of model accuracy and improved simulation speed.
Design methodology of a passive damped modified LCL filter for leakage current reduction in grid‐connected transformerless three‐phase PV inverters
Authors: Giacomini Julian C. , Michels Leandro , Pinheiro Humberto , Rech Cassiano
Published: August 2017

Although grid‐connected transformerless photovoltaic (PV) inverters present higher efficiency and power density compared with inverters with a transformer, the leakage current caused by the inverter common‐mode voltage introduces several problems. Among the techniques to reduce the leakage current, the modified LCL (MLCL) filter with passive damping is an effective and simple solution. However, the classical design of the filter damping resistance is not adequate for ensuring both proper leakage current attenuation and control system stability. Therefore, this study proposes a methodology to design the resistance in a low‐loss passive damping structure applied to the MLCL filter. In addition to the conventional specifications for LCL‐type filters, this study includes the leakage current limit in the design procedure. Simulation and experimental results for a 10 kW PV inverter show the damping resistance impact on the leakage current. The results related to the efficiency and grid inductance variation are also presented. Therefore, it is possible to conclude that the proposed design methodology is very useful for obtaining a damping resistance that ensures control system stability and a leakage current in conformity with PV standards.
A maximum principle for controlled stochastic factor model
Authors: Socgnia Virginie Konlack , Pamen Olivier Menoukeu
Published: August 2017

In the present work, we consider an optimal control for a three-factor stochastic factor model. We assume that one of the factors is not observed and use classical filtering technique to transform the partial observation control problem for stochastic differential equation (SDE) to a full observation control problem for stochastic partial differential equation (SPDE). We then give a sufficient maximum principle for a system of controlled SDEs and degenerate SPDE. We also derive an equivalent stochastic maximum principle. We apply the obtained results to study a pricing and hedging problem of a commodity derivative at a given location, when the convenience yield is not observable.
Nonenzymatic Biomimetic Synthesis of Black Tea Pigment Theaflavins
Authors: Matsuo Yosuke , Tanaka Takashi , Oowatashi Ryosuke , Saito Yoshinori
Published: August 2017

Theaflavins are reddish-orange black tea pigments with a benzotropolone chromophore, and their various biological activities have been reported. Theaflavins are produced by oxidative coupling between catechol-type and pyrogallol-type catechins via bicyclo[3.2.1]octane-type intermediates. In this study, a new method for nonenzymatic biomimetic synthesis of theaflavins was developed using the DPPH radical as an oxidizing agent.
Synthesis of Glycosyl Azides and Their Applications Using CuAAC Click Chemistry to Generate Bis- and Tris(triazolyl)glycosyl Derivatives
Authors: Shamim Anwar , Vasconcelos Stanley , de Oliveira Isadora , Reis Joel , Pimenta Daniel , Zukerman-Schpector Julio , Stefani Hélio
Published: August 2017

2,3-Unsaturated C-(triazolyl)glycosyl acetates have been synthesized from 3,4,6-tri-O-acetyl-d-glucal using C-glycosylation and click chemistry and were then used in a palladium-catalyzed Tsuji–Trost type allylic azidation reaction to afford the corresponding regioisomeric glucal-azide derivatives. Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions with these glucal-based allylic azides using CuI as the catalyst, led to the corresponding glucal-based bis(triazole) derivatives. Performing further functional group modification and another click (CuAAC) reaction with each of these bis(triazolyl) glycosyl derivatives afforded tris(triazolyl)glycosyl derivatives. Two libraries of regioisomeric bis(triazole) derivatives and a small library of regioisomeric tris(triazole) derivatives of glucal were then synthesized using different alkynes.
5,6,7,8-Tetrahydronaphthalen-1-amine as Precursor for Thiazolidi­nones and Benzothiazepinones: Synthesis and Atropisomeric Relationship
Authors: Drawanz Bruna , Zimmer Georgia , Rodrigues Leticia , Nörnberg Andressa , Hörner Manfredo , Frizzo Clarissa , Cunico Wilson
Published: August 2017

The one-pot reaction of 5,6,7,8-tetrahydronaphthalen-1-amine, mercaptoacetic acid, and arenealdehydes having strong and weak electron-withdrawing groups gave the corresponding 1,3-thiazolidin-4-ones (47–70%). When arenealdehydes bearing strong and weak electron-donating groups were used as precursors, the 1,4-benzothiazepin-2-ones were obtained (30–72%) by p-TsOH catalysis. All compounds are unknown and were characterized by GC-MS and NMR techniques, and available crystals by X-ray diffraction studies. The atropisomerism phenomenon was observed in several 1,3-thiazolidin-4-ones as confirmed by VTNMR method. The Tc was established as 332 K and the energy required for the interconversion of one atrop­isomer into another is around 16.8 kcal·mol–1. Chemical quantum calculation and NOESY displayed that more stable isomer has the tetrahydro­naphthalene portion below the five-ring plane. Only a small difference between isomers (–0.21 to –0.84 kcal·mol–1) was observed by calculated energy.
Rectus Muscle Reapproximation at Cesarean Delivery and Postoperative Pain: A Randomized Controlled Trial
Authors: Lyell Deirdre , Naqvi Mariam , Wong Amy , Urban Renata , Carvalho Brendan
Published: August 2017

Objective Rectus muscle reapproximation at cesarean delivery (CD) is performed frequently by some obstetricians; however, the effect on postoperative pain is unclear. To this end, we investigated whether rectus muscle reapproximation increases postoperative pain.

Materials and Methods This is a prospective, double-blind, randomized controlled trial of women undergoing primary CD with singleton or twin pregnancy at >35 weeks' gestation. Women were randomized to rectus muscle reapproximation with three interrupted sutures or no reapproximation. Exclusion criteria were prior cesarean, prior laparotomy, vertical skin incision, active labor, chronic analgesia use, allergy to opioid or nonsteroidal anti-inflammatory drugs, and body mass index ≥ 40. Intra- and postoperative pain management was standardized within the study protocol. The primary outcome was a combined movement pain and opioid use score averaged over the 72-hour study period, called the Silverman integrated assessment. Movement pain scores were assessed at 24, 48, and 72 postoperative hours.

Results In total, 63 women were randomized, of whom 35 underwent rectus muscle reapproximation and 28 did not. Demographic and obstetric variables were similar between groups. Silverman integrated assessment scores during the 72-hour postoperative period were higher in the rectus muscle reapproximation group (15 ± 100% vs. –31 ± 78% difference from the mean; p = 0.04). Operative times were similar between groups (63 ± 15 vs. 65 ± 15 minutes; p = 0.61), and there were no surgical complications in either group. Maternal satisfaction with analgesia at 72 hours was high in both groups (85% [73–90] rectus muscle reapproximation vs. 90% [75–100]; p = 0.16).

Conclusion Rectus muscle reapproximation increased immediate postoperative pain without differences in operative time, surgical complications, or maternal satisfaction. Benefits of rectus muscle reapproximation should be weighed against increased postoperative pain, and analgesia should be planned accordingly.
Dermoid Cyst of the Prepontine Cistern and Meckel's Cave: Illustrative Case and Systematic Review
Authors: Chung Lawrance , Lagman Carlito , Duong Courtney , Nagasawa Daniel , Tucker Alexander , Yong William , Yang Isaac
Published: August 2017

Objective Dermoid cysts are benign, congenital malformations that account for ∼0.5% of intracranial neoplasms. The authors describe a 42-year-old female with a prepontine dermoid cyst who underwent apparent gross total resection (GTR) but experienced cyst recurrence. To date, very few cases of prepontine dermoid cysts have been reported. The prevalent region where these cysts are located can be difficult to determine. In addition, the authors systematically review the literature to characterize the clinical presentation, anatomical distribution, and surgical outcomes of intracranial dermoid cysts.

Design Systematic review.

Setting/Participants PubMed, Web of Science, and Scopus databases.

Main Outcome Measures Extent of resection, symptom improvement, and recurrence rates.

Results A total of 69 patients with intracranial dermoid cysts were identified. Three (4.3%) intracranial dermoid cysts were located in the prepontine cistern. The average age of patients was 33.3 years. The most common presenting symptoms were headache (52.2%) and visual disturbances (33.3%). Intracranial dermoid cysts were distributed similarly throughout the anterior, middle, and posterior cranial fossae (29.0%, 36.2%, and 29.0%, respectively). GTR was achieved in 42.0% of cases. Thirty-four (49.3%) patients experienced symptom resolution. Recurrence rate was 5.8% at a mean follow-up of 2.1 years.

Conclusions Intracranial dermoid cysts most often present as headaches and visual disturbances. Intracranial dermoid cysts were found in the anterior, middle, and posterior cranial fossae at similar frequencies but with clear predilections for the Sylvian fissure, sellar region, and cerebellar vermis. Outcomes following surgical excision of intracranial dermoid cysts are generally favorable despite moderate rates of GTR.
Tuberculosis of the Knee: A Case Report and Literature Review
Authors: Uboldi Francesco , Limonta Silvia , Ferrua Paolo , Manunta Andrea , Pellegrini Antonio
Published: August 2017

Tuberculosis (TB) is currently in resurgence due to immigration from endemic areas. Skeletal TB frequently mimics more common etiologies and can be difficult to diagnose. A case of TB knee arthritis in a young woman with painful and swelling knee is reported here. Arthrotomy was performed and inflamed synovial tissue was found, with multiple rice bodies in the eroded lateral femoral condyle. The patient was treated with an antituberculosis polytherapy and at 1-year follow-up, she reported relief from pain and swelling. We believe that all surgeons assessing patients from TB endemic regions have to adopt an updated approach to TB treatment. Thus, a literature review is also reported here on the current strategies used in different knee TB cases.
Outcomes geplanter außerklinischer und klinischer Low-Risk Geburten in Niedersachsen
Authors: Petersen Antje , Köhler Lea-Marie , Schwarz Christiane , Vaske Bernhard , Gross Mechthild
Published: August 2017

Einleitung Die Sicherheit der außerklinischen Geburt wird international unterschiedlich bewertet. In Deutschland können Frauen mit niedrigem Risiko ihren Geburtsort frei wählen. Landesspezifische Untersuchungen sind bisher selten, jedoch nötig, da die Gesundheitssysteme sehr variieren und eine Vergleichbarkeit der Studien erschweren.

Methoden Klinische und geplante außerklinische Geburten wurden 2005 in Niedersachsen prospektiv mit dem gleichen Dokumentationsinstrument erhoben. Frauen mit Einlingsschwangerschaft in Schädellage mit avisierter vaginaler Geburt ab 34+0 Schwangerschaftswochen post menstruationem wurden eingeschlossen. Von 4 424 Geburtsverläufen wurden anhand von Risikofaktoren 1 273 Geburtsverläufe ausgewählt. Außerklinische und klinische Geburten wurden mittels Odds Ratio, Chi-Quadrat-Test nach Pearson sowie dem Mann-Whitney-Test verglichen.

Ergebnisse Außerklinisch gebaren 152 (36,6%) Erst- und 263 (63,4%) Mehrgebärende, in der Klinik 439 (51,2%) Erst- und 419 (48,8%) Mehrgebärende. Die intrapartale Verlegungsrate vom außerklinischen Setting in die Klinik lag bei 10,1%. Außerklinisch Gebärende waren älter und hatten einen höheren Bildungsstand. Bei den Klinikgeburten hatten Frauen häufiger einen Migrationshintergrund. Außerklinisch Gebärende nahmen häufiger eine Hebammenbetreuung vor und während des Gebärens in Anspruch. Außerklinisch wurde seltener eingeleitet und interveniert. In der Klinik wurden häufiger die Herztöne des Kindes mittels CTG, außerklinisch vor allem intermittierend überwacht. Die Geburtsdauer war bei außerklinisch gebärenden Frauen signifikant länger im Vergleich zu Frauen, die in der Klinik geboren haben (Median: EG: 9,01 h vs. 7,38 h; MG: 4,53 h vs. 4,25 h). Außerklinisch erlebten Erstgebärende (94,7%) häufiger eine Spontangeburt als in der Klinik (73,6%). Bei allen erfassten kindlichen Outcomes, mütterlichem Blutverlust und schweren Dammverletzungen zeigte sich kein Unterschied. Ein intakter Damm und Plazentalösungsstörungen waren in der Klinik seltener.

Diskussion Bei guter Risikobewertung und Verlegungsorganisation bietet eine außerklinische Geburt ein angemessenes Sicherheitsniveau. Die Vorteile der außerklinischen Geburt wie persönliche Betreuung und weniger Interventionen sollten in Klinikkreißsälen integriert werden und können zu einer Verbesserung der Versorgung und Steigerung der Spontangeburtenrate beitragen.
Vestibuläre und okulomotorische Therapie nach Gehirnerschütterung
Authors: Meier Cornelia , Mani Karin , Ventura Alessandra , Bizzini Mario
Published: August 2017

OPTIMALE BEHANDLUNG Nach einem schweren Check persistieren bei einem Eishockeyspieler Kopfschmerzen, Schwindel, Licht- und
Lärmempfindlichkeit – trotz Aufenthalt im Krankenhaus und vierwöchiger Trainingspause. Die bleibenden Symptome fordern eine spezifische und
multidisziplinäre Abklärung sowie eine gezielte und differenzierte Trainingsplanung.
Osteopathie mindert Schmerzen bei Fibromyalgie
Authors: Albers Jessica
Published: August 2017

Randomisierte kontrollierte Studie zur Effektivität zweier osteopathischer Behandlungsansätze für Schmerz, Druckschmerzgrenzen und Schwere
der Erkrankung bei Patienten mit Fibromyalgie.

[Albers J, Schmidt T, Wellmann K, Jäkel A. Effectiveness of two osteopathic treatment approaches on pain, pressure pain threshold and disease
severity in patients with fibromyalgia – a randomized controlled trial. In: Complementary Medicine Research (zur Publikation
angenommen)]
„Editor’s Choice“ – ein neues Angebot an junge Autorinnen und Autoren!
Authors: Singer Dominique
Published: August 2017

Liebe Leserinnen und Leser,

seit einigen Jahren ist die Zeitschrift für Geburtshilfe und Neonatologie (ZGN) um eine behutsame, aber zielstrebige Modernisierung ihres Erscheinungsbildes bemüht. Dabei sind 2 Zielrichtungen zu unterscheiden: Zum einen wurde eine Reihe neuer Rubriken (z. B. Journal Club, Perinatalkonferenz, Perinatalmedizin in Bildern) ins Leben gerufen, die v. a. dem Fortbildungsinteresse einer jüngeren Leserschaft entgegenkommen und entsprechend gut angenommen werden. Zum anderen sollte diese Maßnahme nicht im Widerspruch zu dem Streben nach „wissenschaftlicher Solidität“ in den Kernbereichen einer Zeitschrift stehen, die durch ihren im Titel verankerten interdisziplinären Ansatz ein gewisses Alleinstellungsmerkmal in der deutschsprachigen Perinatologie besitzt.
Fetal Cardiac Myxomas
Authors: Yuan Shi-Min
Published: August 2017

Fetal cardiac myxomas are very rare. To date there has been no representative description of fetal cardiac myxomas. The aim of this study is to highlight the clinical features, possible outcomes and the disparities from the adult cardiac myxomas and other fetal cardiac tumors.

A comprehensive literature review yielded 27 reports including 32 cases of fetal cardiac myxomas.

Apart from the same pedunculated and solitary nature and echogenic appearance, fetal cardiac myxomas differ from those in adults in many aspects, including tumor location, clinical manifestation and malignant potential. Fetal cardiac myxomas are the most common in the left ventricle and the least common in the left atrium. Tumor size and tumor site could be predictive risk factors of adverse cardiac events of fetuses.

Their clinical courses are often benign with fewer cases of adverse cardiac events. Prenatal echocardiography is a reliable diagnostic technique, which can detect cardiac myxomas at as early as 18 weeks gestation. Differential diagnosis should be made from other types of fetal cardiac tumors. Postnatal cardiac myxoma resection may provide a good prognosis.
Cytotoxic Flavones from the Stem Bark of Bougainvillea spectabilis Willd
Authors: Do Lien , Aree Thammarat , Siripong Pongpun , Vo Nga , Nguyen Tuyet , Nguyen Phung , Tip-pyang Santi
Published: August 2017

Five new flavones possessing a fully substituted A-ring with C-6 and C-8 methyl groups, bougainvinones I – M (1–5), along with three known congeners, 2′-hydroxydemethoxymatteucinol (6), 5,7,3′,4′-tetrahydroxy-3-methoxy-6,8-dimethylflavone (7) and 5,7,4′-trihydroxy-3-methoxy-6,8-dimethylflavone (8), were isolated from the EtOAc extract of the stem bark of Bougainvillea spectabilis. Their structures were established by means of spectroscopic data (ultraviolet, infrared, high-resolution electrospray ionization mass spectrometry, and one-dimensional and two-dimensional nuclear magnetic resonance) and single-crystal X-ray crystallographic analysis. The in vitro cytotoxicity of all isolated compounds against five cancer cell lines (KB, HeLa S-3, MCF-7, HT-29, and HepG2) was evaluated. Compound 5 showed promising cytotoxic activity against the KB and HeLa S-3 cell lines, with IC50 values of 7.44 and 6.68 µM. The other compounds exhibited moderate cytotoxicity against the KB cell line.
Inhomogeneity-induced timing jitter of superconducting nanowire single-photon detectors
Authors: Cheng Yuhao , Gu Chao , Hu Xiaolong
Published: August 2017

We show that the distributed electronic and geometric inhomogeneity of a superconducting nanowire induces timing jitter of the resulting single-photon detector and this timing jitter could be further exacerbated by localized constrictions. Due to the distributed inhomogeneity, photons absorbed at different locations of the nanowire generate hotspots that “sense” different local properties of the nanowire during the electro-thermal evolutions and thereby produce varying time delays. The localized constrictions limit the bias current, slow down the Joule-heating process, and consequently increase the average time delays and the inhomogeneity-induced timing jitter. We combine the Monte-Carlo method and the electro-thermal simulation to illustrate the inhomogeneity-induced timing jitter.
Translationally symmetric extended MHD via Hamiltonian reduction: Energy-Casimir equilibria
Authors: Kaltsas D. A. , Throumoulopoulos G. N. , Morrison P. J.
Published: August 2017

The Hamiltonian structure of ideal translationally symmetric extended MHD (XMHD) is obtained by employing a method of Hamiltonian reduction on the three-dimensional noncanonical Poisson bracket of XMHD. The existence of the continuous spatial translation symmetry allows the introduction of Clebsch-like forms for the magnetic and velocity fields. Upon employing the chain rule for functional derivatives, the 3D Poisson bracket is reduced to its symmetric counterpart. The sets of symmetric Hall, Inertial, and extended MHD Casimir invariants are identified, and used to obtain energy-Casimir variational principles for generalized XMHD equilibrium equations with arbitrary macroscopic flows. The obtained set of generalized equations is cast into Grad-Shafranov-Bernoulli (GSB) type, and special cases are investigated: static plasmas, equilibria with longitudinal flows only, and Hall MHD equilibria, where the electron inertia is neglected. The barotropic Hall MHD equilibrium equations are derived as a limiting case of the XMHD GSB system, and a numerically computed equilibrium configuration is presented that shows the separation of ion-flow from electro-magnetic surfaces.
Pulse width and height modulation for multi-level resistance in bi-layer TaOx based RRAM
Authors: Alamgir Zahiruddin , Beckmann Karsten , Holt Joshua , Cady Nathaniel C.
Published: August 2017

Mutli-level switching in resistive memory devices enables a wide range of computational paradigms, including neuromorphic and cognitive computing. To this end, we have developed a bi-layer tantalum oxide based resistive random access memory device using Hf as the oxygen exchange layer. Multiple, discrete resistance levels were achieved by modulating the RESET pulse width and height, ranging from 2 kΩ to several MΩ. For a fixed pulse height, OFF state resistance was found to increase gradually with the increase in the pulse width, whereas for a fixed pulse width, the increase in the pulse height resulted in drastic changes in resistance. Resistive switching in these devices transitioned from Schottky emission in the OFF state to tunneling based conduction in the ON state, based on I-V curve fitting and temperature dependent current measurements. These devices also demonstrated endurance of more than 108 cycles with a satisfactory Roff/Ron ratio and retention greater than 104 s.
Nonlinearity-induced Laguerre-Gauss modes in organic vertical cavity lasers
Authors: Lemke Felix , Kropla Christian , Mischok Andreas , Brückner Robert , Fröb Hartmut , Leo Karl
Published: August 2017

We observe lasing emission from an organic microcavity structure at room temperature with a sunflower-like pattern closely resembling Laguerre-Gauss modes. Simultaneously, measured angle-resolved emission spectra below and above the lasing threshold demonstrate the coexistence of discrete modes, confined in a doughnut-shaped potential, and continuously propagating modes with parabolic dispersion. This phenomenon can be explained by a spatially and intensity-dependent change in the refractive index of the organic material, induced by nonlinearity associated with the bleaching of the dye layer at high excitation intensities. A theoretical model shows that Laguerre-Gauss modes well describe the experimental observation.
Image method for electrostatic energy of polarizable dipolar spheres
Authors: Gustafson Kyle S. , Xu Guoxi , Freed Karl F. , Qin Jian
Published: August 2017

The multiple-scattering theory for the electrostatics of many-body systems of monopolar spherical particles, embedded in a dielectric medium, is generalized to describe the electrostatics of these particles with embedded dipoles and multipoles. The Neumann image line construction for the electrostatic polarization produced by one particle is generalized to compute the energy, forces, and torques for the many-body system as functions of the positions of the particles. The approach is validated by comparison with direct numerical calculation, and the convergence rate is analyzed and expressed in terms of the discontinuity in dielectric contrast and particle density. As an illustration of this formalism, the stability of small particle clusters is analyzed. The theory is developed in a form that can readily be adapted to Monte Carlo and molecular dynamics simulations for polarizable particles and, more generally, to study the interactions among polarizable molecules.
A general, rotating, hard sphere model applied to the transport properties of a low density gas
Authors: Meanwell Michael , Thachuk Mark
Published: August 2017

A general, spherical, rigid model is introduced for describing rotating and translating particles. The model contains a parameter, which we label γ, that smoothly interpolates between the smooth hard sphere (γ = 0) and rough hard sphere (γ = 1) limits. Analytic expressions for transport coefficients are determined for the general model in the low density limit and compared with those for the smooth and rough hard sphere cases. While the diffusion constant decreases monotonically on moving from the smooth to the rough sphere limits, both the viscosity and thermal conductivity first decrease and then increase, thereby producing a minimum between the two limits. This qualitative change in behaviour is new and suggests translational-rotational coupling acts to decrease the values of the transport coefficients (in contrast to the prediction from the rough sphere model). Although the model still has the (known) deficiencies of rigid models, it is more flexible than either the smooth or rough sphere model and should find use in better representing molecular behaviour. The general model provides a consistent representation of the transport coefficients because it has proper, microscopic collision dynamics obeying conservation laws for total momentum, total angular momentum, and total energy.
Massively parallel GPU-accelerated minimization of classical density functional theory
Authors: Stopper Daniel , Roth Roland
Published: August 2017

In this paper, we discuss the ability to numerically minimize the grand potential of hard disks in two-dimensional and of hard spheres in three-dimensional space within the framework of classical density functional and fundamental measure theory on modern graphics cards. Our main finding is that a massively parallel minimization leads to an enormous performance gain in comparison to standard sequential minimization schemes. Furthermore, the results indicate that in complex multi-dimensional situations, a heavy parallel minimization of the grand potential seems to be mandatory in order to reach a reasonable balance between accuracy and computational cost.
Direct measurement of site-specific rates of reactions of H with C3H8, i-C4H10, and n-C4H10
Authors: Lin Chia-Chieh , Chen Wei-Yu , Matsui Hiroyuki , Wang Niann-Shiah
Published: August 2017

We measured the rates of abstraction of a hydrogen atom from specific sites in propane C3H8, 2-methyl propane (i-C4H10), and butane (n-C4H10); the sites are a primary hydrogen of C3H8 and i-C4H10 and a secondary hydrogen of n-C4H10. The excellent reproducibility of conditions of a diaphragm-less shock tube enabled us to conduct comparative measurements of the evolution of H atoms in three mixtures—(i) 0.5 ppm C2H5I + Ar, (ii) 0.5 ppm C2H5I + 50-100 ppm alkane as C3H8 or i-C4H10 or n-C4H10 + Ar, and (iii) the same concentrations of alkane + Ar without C2H5I—in the temperature range 1000–1200 K and at a pressure of 2.0 bars. The net profile of rise and decay of H atoms in the C2H5I + alkane mixture was derived on subtracting the absorbance of (iii) from that of (ii). Measurements of the mixture (iii) are important because the absorption of alkanes at 121.6 nm is not negligible. In the temperature range 1000–1100 K, the rate of decomposition of C2H5I was evaluated directly on analyzing the exponential growth of H atoms in the mixture (i). The rate of decomposition of C2H5I is summarized as ln(k/s−1) = (33.12 ± 1.4) − (25.23 ± 1.5) 103/T (T = 1000–1100 K, P = 2.0 bars); the broadening factor F(T) in the Lindemann-Hinshelwood formula was evaluated in the fall-off region. The site-specific rates of H + (C3–C4) alkanes are summarized as follows: H + C3H8 → H2 + 1-C3H7, ln(k1a) = −(21.34 ± 0.86) − (5.39 ± 0.93)103/T, H + i-C4H10 → H2 + i-C4H9, ln(k2a) = −(20.50 ± 1.36) − (6.14 ± 0.13)103/T, H + n-C4H10 → H2 + 2-C4H9, ln(k3b) = −(21.37 ± 1.15) − (4.83 ± 1.26)103/T. The present experimental results are compared with published results from quantum-chemical calculations of potential-energy surfaces and transition-state theory. The present experiments are consistent with those calculations for the reaction rates for the attack at the primary site for H + C3H8 and H + i-C4H10, but for the attack at the secondary site of n-C4H10, our results are substantially smaller than the computational prediction, which might indicate a hindrance by the C–H bonds of the primary sites that serves to decrease the rate of abstraction from the secondary site of n-C4H10. The influence on the total rates of reactions H + alkane and the group additivity rule are discussed.
Molecular dynamics simulations of fluid cyclopropane with MP2/CBS-fitted intermolecular interaction potentials
Authors: Ho Yen-Ching , Wang Yi-Siang , Chao Sheng D.
Published: August 2017

Modeling fluid cycloalkanes with molecular dynamics simulations has proven to be a very challenging task partly because of lacking a reliable force field based on quantum chemistry calculations. In this paper, we construct an ab initio force field for fluid cyclopropane using the second-order Møller-Plesset perturbation theory. We consider 15 conformers of the cyclopropane dimer for the orientation sampling. Single-point energies at important geometries are calibrated by the coupled cluster with single, double, and perturbative triple excitation method. Dunning’s correlation consistent basis sets (up to aug-cc-pVTZ) are used in extrapolating the interaction energies at the complete basis set limit. The force field parameters in a 9-site Lennard-Jones model are regressed by the calculated interaction energies without using empirical data. With this ab initio force field, we perform molecular dynamics simulations of fluid cyclopropane and calculate both the structural and dynamical properties. We compare the simulation results with those using an empirical force field and obtain a quantitative agreement for the detailed atom-wise radial distribution functions. The experimentally observed gross radial distribution function (extracted from the neutron scattering measurements) is well reproduced in our simulation. Moreover, the calculated self-diffusion coefficients and shear viscosities are in good agreement with the experimental data over a wide range of thermodynamic conditions. To the best of our knowledge, this is the first ab initio force field which is capable of competing with empirical force fields for simulating fluid cyclopropane.
Time and frequency-dependence of the electric field-induced phase transition in BaTiO3-BiZn1/2Ti1/2O3
Authors: Iamsasri Thanakorn , Esteves Giovanni , Choe Hyeokmin , Vogt Marco , Prasertpalichat Sasiporn , Cann David P. , Gorfman Semën , Jones Jacob L.
Published: August 2017

The time and frequency dependence of the electric field-induced phase transition in BaTiO3-BiZn1/2Ti1/2O3 was studied using in situ X-ray diffraction. The kinetics of the field-induced phase transition between cubic and tetragonal phases was described using a modified Kolmogorov-Avrami-Ishibashi (KAI) equation. Unlike previous works, for which some assumptions (e.g., unimodal and Gaussian) on the distribution of transition rates are needed, the present work utilized Bayesian inference and a Markov chain Monte Carlo algorithm to obtain the distribution of transition rates empirically without a priori assumption on the distribution. The results show that the transition rate coefficient increases as the frequency of applied field increases. The mean value of exponent n in the modified-KAI equation was close to 1, implying that the field-induced phase transition is site saturated and the growth of the induced phase occurred primarily from the surface.
Electronic structures and optical properties of Al, Cu, and Ag in zero, two, and three dimensional structures
Authors: Mishra K. C. , Piquette A. , Schmidt P. C. , Johnson K. H.
Published: August 2017

The electronic structures and associated optical properties of aluminum, copper, and silver were investigated in bulk, thin-film and nanoparticle forms using first-principles band structure methods. The calculations show the progression from continuous bands to subbands to discrete states as spatial confinement is imposed in one and three dimensions. The associated optical properties described by the imaginary component of the dielectric function, ε2(ω), were also investigated. The interband contributions to ε2(ω) were calculated from the band structure, while the intraband contributions were calculated using the Drude theory for free electrons. Both contributions to ε2(ω) are needed to understand the optical properties of metals and to interpret their reflectance spectra. The interband transitions need to be considered to explain reflectivity at energies lower than the plasma frequencies, but not all interband transitions result in reflectance peaks since they are significantly weaker compared to the intraband contributions at lower energies. We have studied the dependence of the density of states on the choice of exchange potentials. In copper, where ultraviolet photoelectron spectroscopy data are available, using a hybrid functional, Heyd-Scuseria-Ernzerhof, leads to better agreement with the experiment than when using the generalized gradient approximation potential, and it reproduces correctly the variation of binding energy of the d electrons going from bulk to thin film. The corresponding dependence exchange potential for silver is less severe.
Effect of PEDOT band structure on conductive polymer-insulator-silicon junctions
Authors: Demtchenko S. , Tarr N. G. , McGarry S.
Published: August 2017

The effect of replacing a conventional metal with an organic conductive polymer in a metal-insulator-semiconductor (MIS) diode is examined theoretically and experimentally. Two sets of MIS diodes, one with gold and the other with poly(3,4-ethylenedioxythiophene) as the top “metal”, have been manufactured in parallel. Despite the two conductors having similar reported work functions of 5.1 eV to 5.2 eV, the hybrid devices exhibited far lower current densities as compared to their inorganic counterparts. Simulating the device behaviour reveals the limited width of the energy bands in the conductive polymer as the reason for low current density in the hybrid MIS.