bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel genetic tools that enable highly pure protein production in Trichoderma reesei
Authors: Rantasalo Anssi , Vitikainen Marika , Paasikallio Toni , Jäntti Jussi , Landowski Christopher P. , Mojzita Dominik
Published: March 2019

Trichoderma reesei is an established protein production host with high natural capacity to secrete enzymes. The lack of efficient genome engineering approaches and absence of robust constitutive gene expression systems limits exploitation of this organism in some protein production applications. Here we report engineering of T. reesei for high-level production of highly enriched lipase B of Candida antarctica (calB) using glucose as a carbon source. Multiplexed CRISPR/Cas9 in combination with the use of our recently established synthetic expression system (SES) enabled accelerated construction of strains, which produced high amounts of highly pure calB. Using SES, calB production levels in cellulase-inducing medium were comparable to the levels obtained by using the commonly employed inducible cbh1 promoter, where a wide spectrum of native enzymes were co-produced. Due to highly constitutive expression provided by the SES, it was possible to carry out the production in cellulase-repressing glucose medium leading to around 4 grams per liter of fully functional calB and simultaneous elimination of unwanted background enzymes.
Myc-driven chromatin accessibility regulates Cdc45 assembly into CMG helicases
Authors: Nepon-Sixt Brook S. , Bryant Victoria L. , Alexandrow Mark G.
Published: March 2019

Myc-driven tumorigenesis involves a non-transcriptional role for Myc in over-activating replication origins. We show here that the mechanism underlying this process involves a direct role for Myc in activation of Cdc45-MCM-GINS (CMG) helicases at Myc-targeted sites. Myc induces decondensation of higher-order chromatin at targeted sites and is required for chromatin access at a chromosomal origin. Myc-driven chromatin accessibility promotes Cdc45/GINS recruitment to resident MCMs, and activation of CMGs. Myc-Box II, which is necessary for Myc-driven transformation, is required for Myc-induced chromatin accessibility, Cdc45/GINS recruitment, and replication stimulation. Myc interactors GCN5, Tip60, and TRRAP are essential for chromatin unfolding and recruitment of Cdc45, and co-expression of GCN5 or Tip60 with MBII-deficient Myc rescues these events and promotes CMG activation. Finally, Myc and Cdc45 interact and physiologic conditions for CMG assembly require the functions of Myc, MBII, and GCN5 for Cdc45 recruitment and initiation of DNA replication.
Soliton collision induced explosions in a mode-locked fibre laser
Authors: Peng Junsong , Zeng Heping
Published: March 2019

Soliton explosion refers to a striking nonlinear dynamics in dissipative systems. In this state, a dissipative soliton collapses but returns back to its original state afterwards. Yet, the origin of such exotic soliton dynamics remains elusive. Here it is revealed that soliton collision can induce soliton explosions in a mode-locked fibre laser, benefiting from synchronous measurements of the spatio-temporal intensity evolution and the real-time spectra evolution using dispersive Fourier transform. Up to seven nonlinear regimes are observed successively in the laser by increasing the pump power only, including single-pulse mode locking, standard soliton explosions, noise-like mode locking, stable double pulsing, soliton collision induced explosions, soliton molecules, and double-pulse noise-like mode locking. These experimental findings are conducive to understand complex soliton dynamics in many nonlinear dissipative systems.
Carbon Nanomaterials in Hydrogenation Catalysis
Authors: Furimsky Edward
Published: March 2019

Hydrogenation is a key reaction in both the food and petrochemical industries, where it is used to reduce carbon–carbon double bonds. Without a catalyst, hydrogenation reactions require extreme temperatures to occur, meaning catalysts are essential for the reaction to be industrially useful. During the past decade, the properties of many carbon nanomaterials that are relevant to hydrogenation catalysis have been described, including carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon nanohorns (CNHs), graphene oxide (GO), reduced graphene oxides (rGO) and fullerenes, that are relevant to hydrogenation catalysis, have been described. For many of these the production methods have advanced to the commercial stage. Numerous studies on the development of catalysts on carbon nano-supports have appeared in the scientific literature and these catalysts have shown remarkable activity and specificity.

Carbon Nanomaterials in Hydrogenation Catalysis is a valuable reference for researchers and chemical engineers working on improving hydrogenation processes and those interested in applications for carbon nanomaterials. Covering their production, modification and applications as a catalyst support this book provides an in-depth review of the current state-of-the art in using carbon nanomaterials for hydrogenation reactions.
Emerging investigator series: oxidative potential of diesel exhaust particles: role of fuel, engine load, and emissions control
Authors: Sharma Naman , Vanderheyden Cody , Klunder Kevin , Henry Charles S. , Volckens John , Jathar Shantanu H.
Published: March 2019

Biodiesel and the use of an emissions control system significantly reduced the oxidative potential of diesel exhaust particles, which correlated with reduction in emissions of elemental carbon.
Fluorescence imaging of lysosomal hydrogen selenide under oxygen-controlled conditions
Authors: Tian Yong , Xin Fangyun , Jing Jing , Zhang Xiaoling
Published: March 2019

A lysosome-targetable fluorescent probe was exploited to monitor the H2Se concentration fluctuations in lysosomes under oxygen-controlled conditions.
Green and scalable synthesis of nitro- and amino-functionalized UiO-66(Zr) and the effect of functional groups on the oxidative desulfurization performance
Authors: Ye Gan , Qi Hui , Zhou Wei , Xu Wei , Sun Yinyong
Published: March 2019

Nitro- and amino-functionalized UiO-66(Zr) have great potential in some applications.
Heterogeneous palladium-based catalyst promoted reduction of oximes to amines: using H2 at 1 atm in H2O under mild conditions
Authors: Liu Yaxu , Quan Ziyi , He Shaopo , Zhao Zexi , Wang Jiang , Wang Bo
Published: March 2019

A highly active palladium-based heterogeneous catalyst with excellent activity for the hydrogenation of oximes to form amines was prepared.
Identification of selective protein–protein interaction inhibitors using efficient in silico peptide-directed ligand design
Authors: Beekman Andrew M. , Cominetti Marco M. D. , Walpole Samuel J. , Prabhu Saurabh , O'Connell Maria A. , Angulo Jesus , Searcey Mark
Published: March 2019

Development of selective hDM2/X p53 inhibitors is key to further develop this anticancer target. This method displayed a 50% success rate and identified hDMX selective compounds.
Special layer-structured WS2nanoflakes as high performance sodium ion storage materials
Authors: Liu Mao-Cheng , Zhang Hui , Hu Yu-Xia , Lu Chun , Li Jun , Xu Ying-Ge , Kong Ling-Bin
Published: March 2019

Wrinkled WS2nanoflakes as electrode materials for sodium ion storage, exhibiting superior electrochemical performance.
Microalgae as a renewable fuel resource: a comparative study on the thermogravimetric and kinetic behavior of four microalgae
Authors: Vuppaladadiyam Arun K. , Zhao Ming , Memon Muhammad Zaki , Soomro Abdul F.
Published: March 2019

Four different microalgae,Chlorella vulgaris(CV),Spirulina(SP),Chroococcus(CC) and mix culture (MC), were pyrolyzed at heating rates of 10, 15 and 20 °C min−1up to 800 °C in a thermogravimetric analyzer coupled with a mass spectrometer to investigate their pyrolytic characteristics.
Boosting the electrochemical performance through proton transfer for the Zn-ion hybrid supercapacitor with both ionic liquid and organic electrolytes
Authors: Zhou Haitao , Liu Chao , Wu Jian-Chun , Liu Menghao , Zhang Dong , Song Honglei , Zhang Xiaoyun , Gao Hongquan , Yang Jianhong , Chen De
Published: March 2019

An increase of the Zn-ion hybrid SC performance by carbon surface chemistry through the pseudocapacitance induced by proton transfer.
Asymmetric superwetting configuration of Janus membranes based on thiol–ene clickable silane nanospheres enabling on-demand and energy-efficient oil–water remediation
Authors: Li Xiangyu , Zhang Weifeng , Qu Ruixiang , Liu Yanan , Wei Yen , Feng Lin
Published: March 2019

A facile and universal strategy is presented to prepare Janus membranes based on thiol–ene click chemistry, endowing multifarious substrates with designed Janus performance.
Biochemical analysis of antimicrobial peptides in two different Capsicum genotypes after fruit infection by Colletotrichum gloeosporioides
Authors: Maracahipes Álan C. , Taveira Gabriel B. , Mello Erica O. , Carvalho André O. , Rodrigues Rosana , Perales Jonas , Teixeira-Ferreira André , Silva Marciele S. , Rocha Gustavo L. , Fernandes Kátia Valevski Sales , Gomes Valdirene M.
Published: March 2019

There are several phytosanitary problems that have been causing serious damage to the Capsicum crops, including anthracnose. Upon attack by certain pathogens, various protein molecules are produced, which are known as proteins related to pathogenesis (PR proteins), including antimicrobial peptides such as protease inhibitors, defensins and lipid transfer proteins (LTPs). The objective of this work is to identify antimicrobial proteins and/or peptides of two genotypes from Capsicum annuum fruits infected with Colletotrichum gloeosporioides. The fungus was inoculated into Capsicum fruits by the deposition of a spore suspension (106 conidia ml−1), and after 24 and 48 h intervals, the fruits were removed from the humid chamber and subjected to a protein extraction process. Protein analysis of the extracts was performed by tricine gel electrophoresis and Western blotting. The distinctive bands between genotypes in the electrophoresis profiles were subjected to mass spectrometry sequencing. Trypsin inhibition assays, reverse zymographic detection of protease inhibition and β-1,3-glucanase activity assays were also performed and extracts were also tested for their ability to inhibit the growth of C. gloeosporioides fungi ‘in vitro’. There were several low molecular weight proteins in all treated samples, and some treatments in which antimicrobial peptides such as defensin, lipid transfer protein (LTP) and protease inhibitor have been identified. It was shown that the green fruits are more responsive to infection, showing the production of antimicrobial peptides in response to injury and inoculation of the fungus, what did not occur in ripe fruits under any treatment.
Association between polymorphism in the promoter region of lncRNA GAS5 and the risk of colorectal cancer
Authors: Wang Yajie , Wu Shenshen , Yang Xi , Li Xiaobo , Chen Rui
Published: March 2019

The growth arrest special 5 (GAS5), as a research hotspot of long noncoding RNAs (lncRNAs), has been reported to be associated with colorectal cancer (CRC). However, the association between polymorphisms in GAS5 and the risk of CRC was not clear. In the present study, a case–control study in 1078 CRC patients and 1175 matched healthy controls was performed to evaluate the association between the potential functional genetic variants in GAS5 and the risk of CRC. PCR-TaqMan, qPCR, dual-luciferase assay, electrophoretic mobility shift assay (EMSA), flow cytometry, migration and invasion assays were performed to evaluate the function of polymorphism. Results showed that subjects carrying the rs55829688 CT/TT genotypes had a significantly higher risk of CRC when compared with the CC genotype. Further qPCR assay confirmed that the CRC tissues with rs55829688 CT/TT genotypes had a higher GAS5 mRNA expression level. The dual-luciferase assay, qPCR and EMSA assay revealed that rs55829688 T>C polymorphism could decrease the expression level of GAS5 by impacting the binding ability of the transcription factor Yin Yang-1 (YY1) to the GAS5 promoter region. The expression of apoptosis-related proteins were detected by Western blot. Further, flow cytometry, migration, and invasion experiments showed that GAS5 repressed apoptosis and increased invasion and migration capability of CRC cells. Taken together, our findings provided evidence that the rs55829688 variant in the GAS5 promoter was associated with the risk of CRC and decreased expression of GAS5 by affecting the binding affinity of the transcription factors YY1 to GAS5.
Chromatin structures condensed by linker histones
Authors: Zhou Bing-Rui , Bai Yawen
Published: March 2019

In eukaryotic cells, genomic DNA exists in the form of chromatin through association with histone proteins, which consist of four core histone (H2A, H2B, H3, and H4) families and one linker histone (H1) family. The core histones bind to DNA to form the nucleosome, the recurring structural unit of chromatin. The linker histone binds to the nucleosome to form the next structural unit of chromatin, the chromatosome, which occurs dominantly in metazoans. Linker histones also play an essential role in condensing chromatin to form higher order structures. Unlike the core histones in the formation of the nucleosome, the role of linker histone in the formation of the chromatosome and high-order chromatin structure is not well understood. Nevertheless, exciting progress in the structural studies of chromatosomes and nucleosome arrays condensed by linker histones has been made in the last several years. In this mini-review, we discuss these recent experimental results and provide some perspectives for future studies.
One ring to bind them – Cohesin’s interaction with chromatin fibers
Authors: Moronta-Gines Macarena , van Staveren Thomas R.H. , Wendt Kerstin S.
Published: March 2019

In the nuclei of eukaryotic cells, the genetic information is organized at several levels. First, the DNA is wound around the histone proteins, to form a structure termed as chromatin fiber. This fiber is then arranged into chromatin loops that can cluster together and form higher order structures. This packaging of chromatin provides on one side compaction but also functional compartmentalization. The cohesin complex is a multifunctional ring-shaped multiprotein complex that organizes the chromatin fiber to establish functional domains important for transcriptional regulation, help with DNA damage repair, and ascertain stable inheritance of the genome during cell division. Our current model for cohesin function suggests that cohesin tethers chromatin strands by topologically entrapping them within its ring. To achieve this, cohesin’s association with chromatin needs to be very precisely regulated in timing and position on the chromatin strand. Here we will review the current insight in when and where cohesin associates with chromatin and which factors regulate this. Further, we will discuss the latest insights into where and how the cohesin ring opens to embrace chromatin and also the current knowledge about the ‘exit gates’ when cohesin is released from chromatin.
CRSO approach for microgrid power dispatching
Authors: Qiu Haifeng , Gu Wei , Li Peng , Zhang Xuesong , Long Huan , Wu Zhi
Published: March 2019

The optimal dispatch of microgrids is greatly challenged by various uncertainties, introduced by dynamic power fluctuations in loads and variations in renewable energy sources. To depress the over‐conservativeness of traditional robust optimisation, this study puts forward a two‐stage coupled robust and stochastic optimal (CRSO) dispatching model with mixed integer recourse for the islanded hybrid AC/DC microgrid. The CRSO model comprehensively considers the uncertainties in source–load power and bidirectional converter overhauling, and the stochastic source–load uncertainty sets are constructed by interval partitioning methods. The CRSO model optimises the binary states of the diesel generator and the bidirectional converter in the first stage, and the second stage obtains the flexible operating states and power of each unit. The daily worst‐case operation cost is minimised by the nested column‐and‐constraint generation algorithm. Numerical simulations have validated the rationality and superiority of the developed dispatching model and its solution method.
Common strategy to improve community detection performance based on the nodes’ property
Authors: Du Wei , He Xiaochen
Published: March 2019

Improving the community detection algorithm is of great importance. The authors propose a novel method based on the nodes’ property in order to detect the community structure. Given a detected community structure, in which nodes have their community signals, the value of the modularity can be changed if a node's community sign change to other communities’ signs. Accordingly, the new method readjusts the affiliation between a node and its community in order to raise the modularity value. Experimental results of the detection for a list of open‐source networks show that the proposed algorithm can detect better community structure than classic methodologies based on modularity.
Second‐order DE algorithm
Authors: Zhao Xinchao , Xu Guangzhi , Liu Dongyue , Zuo Xingquan
Published: March 2019

Differential evolution (DE) is a robust, efficient and simple evolutionary algorithm for various optimisation and engineering problems. It has several outstanding features such as low time complexity, ease to use and robust steadiness. So it is becoming more and more popular and is widely used in more and more applications. However, many questions are deserving to consider the critical balance between global exploration and neighbourhood exploitation. The difference vector of the mutation operator for the direction and neighbour information has not been fully exploited. Therefore, a second‐order difference vectors based DE, SODE, is proposed, which can efficiently utilise different direction information from the second‐order difference vector. The optimal second‐order difference mechanisms are proposed for DE/rand/1 and DE/best/1 to utilise the direction and neighbour information from difference vector. Then, it will guide the individuals toward the possible more encouraging areas. Extensive experiments and comprehensive comparisons show that the second‐order differenced mechanism in SODE is much better than the classical first‐order difference mechanisms based mutation strategy – ‘DE/rand/1’ and ‘DE/best/1’ as far as the converging and steady performance.
Retinal image segmentation using double‐scale non‐linear thresholding on vessel support regions
Authors: Li Qingyong , Zheng Min , Li Feng , Wang Jianzhu , Geng Yangli‐ao , Jiang Haibo
Published: March 2019

Retinal vessel segmentation is a critical indicator of diagnosis, screening, and treatment of cardiovascular and ophthalmologic diseases. Due to the fact that the retinal vessels usually have some tiny structures and blurred boundaries, especially with remarkable noises, it is difficult to correctly segment the vascular networks. In this study, the authors propose a double‐scale non‐linear thresholding method based on vessel support regions. First, the double‐scale filtering method is applied to enhance the contrast between the foreground vascular and the background stuffs. Second, they segment the fine and coarse vessels by the corresponding adaptive local thresholding and fixed‐ratio thresholding method. Finally, they obtain the binary segmentation by fusion of fine and coarse vessels. Experiments are conducted on the publicly available DRIVE and STARE datasets, which show the effectiveness of the proposed method on retinal vessel segmentation.
Visual navigation method for indoor mobile robot based on extended BoW model
Authors: Li Xianghui , Li Xinde , Khyam Mohammad Omar , Luo Chaomin , Tan Yingzi
Published: March 2019

This article proposes a new navigation method for mobile robots based on an extended bag of words (BoW) model for general object recognition in indoor environments. The scale‐invariant feature transform (SIFT)‐detection algorithm with the graphic processing unit (GPU) acceleration technology is used to describe feature vectors in this model. First, in order to add some redundant image information, statistical information of the spatial relationships of all the feature points in an image, i.e. relative distances and angles, is used to extend the feature vectors in the original BoW model. Then, the support vector machine (SVM) classifier is used to classify objects. Also, in order to navigate conveniently in unknown and dynamic indoor environments, a type of human–robot interaction method based on a hand‐drawn semantic map is considered. The experimental results show that this new navigation technology for indoor mobile robots is very robust and highly effective.
Intensity contrast of solar network and faculae
Authors: Yeo K. L. , Krivova N. A.
Published: March 2019

Aims. We aim to gain insight into the effect of network and faculae on solar irradiance from their apparent intensity.

Methods. Taking full-disc observations from the Solar Dynamics Observatory, we examined the intensity contrast of network and faculae in the continuum and core of the Fe I 6173 Å line and 1700 Å, including the variation with magnetic flux density, distance from disc centre, nearby magnetic fields, and time.

Results. The brightness of network and faculae is believed to be suppressed by nearby magnetic fields from its effect on convection. We note that the degree of magnetically crowding of an area also affects the magnetic flux tube sizes and the depth at which magnetic concentrations are embedded in intergranular lanes, such that intensity contrast can be enhanced in magnetically crowded areas at certain flux densities and distances from disc centre. The difference in intensity contrast between the quiet-Sun network and active region faculae, noted by various studies, arises because active regions are more magnetically crowded and is not due to any fundamental physical differences between network and faculae. These results highlight that solar irradiance models need to include the effect of nearby magnetic fields on network and faculae brightness. We found evidence that suggests that departures from local thermal equilibrium (LTE) might have limited effect on intensity contrast. This could explain why solar irradiance models that are based on the intensity contrast of solar surface magnetic features calculated assuming LTE reproduce the observed spectral variability even where the LTE assumption breaks down. Certain models of solar irradiance employ chromospheric indices as direct indications of the effect of network and faculae on solar irradiance. Based on past studies of the Ca II K line and on the intensity contrast measurements derived here, we show that the fluctuations in chromospheric emission from network and faculae are a reasonable estimate of the emission fluctuations in the middle photosphere, but not of those in the lower photosphere. This is due to the different physical mechanisms that underlie the magnetic intensity enhancement in the various atmospheric regimes, and represents a fundamental limitation of these solar irradiance models. Any time variation in the radiant properties of network and faculae is, of course, relevant to their effect on solar irradiance. The data set, which extends from 2010 to 2018, indicates that their intensity contrast was stable to about 3% in this period.

Conclusions. This study offers new insights into the radiant behaviour of network and faculae, with practical implications for solar irradiance modelling.
Qualitätssicherung
Authors: Bubenzer Rainer
Published: March 2019

Anlässlich des „4. Internationalen Tags der Patientensicherheit“ informierten Vertreter des Aktionsbündnisses Patientensicherheit e. V. über Chancen und Probleme bei der Patientensicherheit in einem zunehmend digitalisierten Gesundheitswesen. Die APS-Vorsitzende Hedwig Françoise-Kettner betonte, dass „wir die Digitalisierung als Chance für den weiteren Ausbau der Patientensicherheit im Gesundheitswesen sehen“. Denn „durch digitale Anwendungen können Schnittstellen und Prozesse zwischen Haus- und Fachärzten, zwischen ambulantem und stationärem Bereich sowie der Medikamentenabgabe in den Apotheken besser miteinander verbunden werden“. So kann der Informationsfluss erhöht, die Kommunikation im Gesundheitswesen deutlich verbessert und Missverständnisse vermieden werden.
Neurointensivmedizin: aneurysmatische Subarachnoidalblutung – State of the Art
Authors: Müller Daniela , Müller Oliver
Published: March 2019

Die spontane, nicht traumatische Subarachnoidalblutung ist eine lebensbedrohliche Erkrankung, die mit vielfältigen Komplikationen und einer hohen Morbidität und Mortalität vergesellschaftet ist. In den ersten 24 Stunden hat die Ausschaltung der Blutungsursache Vorrang. Die Patienten sollen intensivmedizinisch überwacht und behandelt werden. Stringente Diagnostik und konsequente Behandlung verbessern das Outcome der Patienten nachweislich.
Cerebral and Muscle Oxygenation during Repeated Shuttle Run Sprints with Hypoventilation
Authors: Woorons Xavier , Dupuy Olivier , Mucci Patrick , Millet Gregoire P. , Pichon Aurelien
Published: March 2019

Ten highly-trained Jiu-Jitsu fighters performed 2 repeated-sprint sessions, each including 2 sets of 8 x ~6 s back-and-forth running sprints on a tatami. One session was carried out with normal breathing (RSN) and the other with voluntary hypoventilation at low lung volume (RSH-VHL). Prefrontal and vastus lateralis muscle oxyhemoglobin ([O2Hb]) and deoxyhemoglobin ([HHb]) were monitored by near-infrared spectroscopy. Arterial oxygen saturation (SpO2), heart rate (HR), gas exchange and maximal blood lactate concentration ([La]max) were also assessed. SpO2 was significantly lower in RSH-VHL than in RSN whereas there was no difference in HR. Muscle oxygenation was not different between conditions during the entire exercise. On the other hand, in RSH-VHL, cerebral oxygenation was significantly lower than in RSN (−6.1±5.4 vs−1.5±6.6 µm). Oxygen uptake was also higher during the recovery periods whereas [La]max tended to be lower in RSH-VHL. The time of the sprints was not different between conditions. This study shows that repeated shuttle-run sprints with VHL has a limited impact on muscle deoxygenation but induces a greater fall in cerebral oxygenation compared with normal breathing conditions. Despite this phenomenon, performance is not impaired, probably because of a higher oxygen uptake during the recovery periods following sprints.
ASH 2018: Weitere Erfolge, aber auch neue Fragen
Authors: Arnheim Katharina
Published: March 2019

Die Entwicklung von CAR-T-Zell-Therapien hat das Behandlungsspektrum (chimärer Antigen-Rezeptor) für mehrere aggressive hämatologische Neoplasien erweitert. Auf der Jahrestagung der American Society of Hematolgy (ASH) wurden Ende 2018 vielversprechende Langzeitdaten vorgestellt, die für eine anhaltende Effektivität dieser Strategie mit Ausbildung eines Plateaus in der Überlebenskurve sprechen.
Gründe für den Ausstieg aus dem Arztberuf und Determinanten, eine ärztliche Tätigkeit wiederaufzunehmen: eine qualitative Studie mit ehemaligen Teilnehmern eines Wiedereinstiegsseminars
Authors: Izaguirre Anna-Lena Dávila , Schneider Dagmar , Steinhäuser Jost
Published: March 2019

Hintergrund In Deutschland existiert ein zunehmender Bedarf an Ärzten. Zeitgleich gibt es viele approbierte Ärzte, die nicht ärztlich tätig sind. Diese wieder für eine ärztliche Tätigkeit zu gewinnen, wäre eine Maßnahme, dem Gesundheitssystem zeitnah Ärzte zuzuführen. Ziele der Studie waren daher die Exploration individueller Gründe für den Berufsausstieg sowie für die Entscheidung, zurück in den ärztlichen Beruf zu kehren. Ferner sollte der Stellenwert einer Teilnahme an einem Wiedereinstiegsseminar bei diesem Prozess erhoben werden.

Methodik Im Rahmen einer qualitativen Studie wurden 28 halbstrukturierte Interviews mit ehemaligen Teilnehmern an einem Wiedereinstiegsseminar der Bayerischen Landesärztekammer geführt. Diese wurden mit einem Diktiergerät aufgenommen, pseudonymisiert, transkribiert und entsprechend der qualitativen Inhaltsanalyse nach Mayring ausgewertet.

Ergebnisse Gründe, die zu einer Berufspause führten, waren die Familiensituation, unattraktive Arbeitsbedingungen, ein Wohnortswechsel sowie die Stellensituation zu Zeiten der „Ärzteschwemme“. Beweggründe für die Wiederaufnahme der ärztlichen Tätigkeit waren weniger Anforderungen durch die Familie, finanzielle Notwendigkeit, die Befürchtung, den beruflichen Anschluss zu verpassen, Unterforderung in der aktuellen Tätigkeit sowie Wunsch nach Bestätigung. Das Wiedereinstiegsseminar wurde mehrheitlich als „ausschlaggebend“ auf dem Weg zurück in die ärztliche Tätigkeit genannt. Positive Aspekte waren hier der Austausch mit Gleichgesinnten und das wiedergewonnene Selbstvertrauen in die eigenen Fähigkeiten.

Schlussfolgerung Die Vereinbarkeit von Familie und Beruf zu ermöglichen, ist eine zentrale Aufgabe, um dem Verlust von hochqualifizierten Arbeitskräften vorzubeugen. Wiedereinstiegsseminare sollten gezielt die Aspekte Vereinbarkeit von Familie und Beruf, Ängste und Peeraustausch adressieren.
Development and Validation of a UHPLC-DAD Method for the Quantitative Analysis of Major Dihydrochalcone Glucosides from Thonningia sanguinea VAHL
Authors: Pompermaier Luca , Schwaiger Stefan , Mawunu Monizi , Lautenschlaeger Thea , Stuppner Hermann
Published: March 2019

Thonnigia sanguinea is a plant widely used in traditional African medicine against a variety of diseases. The obligate parasite is growing throughout tropical African forests and utilizes a large variety of hosts. Dihydrochalcone glucoside derivatives isolated from the subaerial parts of this plant were identified as potential antidiabetic lead compounds. In this study, an ultrahigh-performance liquid chromatographic method coupled with a photodiode array detector was developed for the quantitation of six major dihydrochalcone derivatives. The analytes were baseline separated in complex samples within 14 minutes on a Phenomenex Luna Omega 1.6 µm C18 column using a mobile phase consisting of water and acetonitrile (each + 0.01% trifluoroacetic acid) in gradient elution. Method validation confirmed the selectivity, linearity (R2 ≥ 0.9992), precision (inter-day ≤ 1.98%, intraday ≤ 2.00%), and accuracy (recovery rates of 97.4 – 106.3% for all analytes). At 280 nm, the LODs and LOQs were found to be lower than 1.42 and 4.30 µg/mL, respectively. Eight plant batches from the northern Angolan province of Uíge (collected in the wild or bought on markets) were extracted with methanol using an ultrasound-assisted extraction protocol and subsequently analyzed with the validated method. Results indicated high contents of dihydrochalcone glucosides in all eight samples. Most notably, the two bioactive constituents thonningianin A and B were present in fairly large amounts (2.42 – 5.35 w%).
Trigeminal Neuralgia Caused by Cerebellopontine Angle Tumors: Surgical Series
Authors: Meguins Lucas , Rodrigues Thayanna , Caramanti Ricardo , Rocha Carlos , Laurenti Matheus , Góes Mario , de Moraes Dionei , Tognola Waldir
Published: March 2019

Introduction Cerebellopontine angle (CPA) tumors represent an important cause of persistent and refractory trigeminal neuralgia (TN). It is believed that ∼ between 1 and 9.9% of the cases of patients presenting with TN painful manifestation are caused by space-occupying lesions.

Objective The objective of the present study is to describe the clinical and surgical experience of the operative management of patients presenting with secondary type TN associated with CPA tumors.

Method An observational investigation was conducted with data collection from patients with secondary type TN associated with CPA tumors who were treated with surgical resection of the space-occupying lesion and decompression of the trigeminal nerve from January 2013 to November 2016 in 2 different centers in the western region of the state of São Paulo, Brazil.

Results We operated on 11 consecutive cases in which TN was associated with CPA during the period of analysis. Seven (63.6%) patients were female, and 4 (36.4%) were male. Seven (63.6%) patients presented with right-side symptoms, and 4 (36.4%) presented with left-side symptoms. After 2 years of follow-up, we observed that 8 (72.7%) patients showed a complete improvement of the symptoms, with an excellent outcome, and that 3 (27.3%) patients showed an incomplete improvement, with a good outcome. No patient reported partial improvement or poor outcome after the follow-up. There was no operative mortality.

Conclusion Cerebellopontine angle tumors represent an important cause of TN and must be included in the differential diagnosis of patients presenting with refractory and persistent symptoms. Surgical treatment with total resection of the expansive lesion and effective decompression of the trigeminal nerve are essential steps to control the symptoms.
Surgical Treatment of Lumbosacral Discospondylitis with Gentamicin-Impregnated Polymethylmethacrylate Cement and Omentalization
Authors: Manou Maria , Jeandel Aurélien , Blot Stéphane , Moissonnier Pierre
Published: March 2019

Objective The aim of this study was to describe a novel technique using a gentamicin-impregnated polymethylmethacrylate (PMMA) plug for the surgical treatment of lumbosacral discospondylitis with concomitant instability.

Clinical Report A 7-year-old male German Shepherd dog with lumbosacral (LS) discospondylitis and previously diagnosed with degenerative lumbosacral disease underwent ventral slot and distraction of the L7 to S1 intervertebral space with a gentamicin-impregnated PMMA plug. The lumbosacral joint was accessed via the abdomen. Samples were collected for bacterial culture and sensitivity, fungal culture and histopathological examination. The surgical site was omentalized. Long-term oral antimicrobials were administered.

Results Clinical improvement was seen immediately after surgery. Complete return to previous activity level was observed 12 months after surgery. Follow-up radiographs 18 months after the procedure revealed no implant migration.

Clinical Significance The gentamicin-impregnated PMMA plug in addition to the surgical debridement seemed to be an effective way for short-term distraction, potentially contributing, along with the appropriate antimicrobial therapy and analgesia, to alleviation of pain immediately after surgery and providing for a good short-term outcome, in this clinical case. The use of cement plugs as sole devices in the LS joint warrants further study.
Antimicrobial Activity of Glass Ionomer Cements with Chlorhexidine and Propolis: An In Vitro Study
Authors: Tuncdemir Makbule Tugba , Ugur Ayşe Ruveyda , Ozdemir Bilgen
Published: March 2019

The aim of this study was to evaluate the antibacterial effect of conventional glass ionomer cement with the addition of antibacterial constituents in its liquid preparation. Two groups of glass ionomers prepared with propolis and chlorhexidine and a third group without any additive used as control were sterilized by low-temperature hydrogen peroxide plasma sterilizer at the sterilization unit. Seven to eight disk-shaped restorative materials of each group were placed on the Mueller Hinton Agar with sheep blood 5% v/v, on which Streptococcus mutans inoculated. The plates were incubated at 37°C in 5% CO2 for 24 to 48 hours. After 24-hour and 48-hour-incubation, inhibition zone diameters of each restorative materials were measured. No distinct inhibition zone was reported; only a slight zone (6 mm) around the contact surfaces of each material was observed after the 24-hour and 48-hour incubations. No significant difference was observed in the inhibition zone diameters between the two test groups and control. Within the limitations of this study, results revealed that there was no antibacterial difference among glass ionomers prepared with propolis and chlorhexidine.
Compression of an accelerated plasma cloud in a cone
Authors: Manegold T. , Benzing C. , Faik S. , Iberler M. , Michel A. , Tavana P. , Wiechula J. , Jacoby J.
Published: March 2019

This paper describes first results of a novel compression method for a plasma by acceleration into a glass cone. The plasma is generated by a pulsed-power-driven coaxial plasma accelerator, prefilled with 2% hydrogen in a helium mixture. The pulse forming network of the experiment has a total capacitance of 27 μF at a maximum voltage of 10 kV. The low inductance of 130 nH leads to an average frequency of about 86 kHz and high current rise rates in the 1011 As range. Due to the high current of up to 150 kA, the Lorentz force accelerates the plasma depending on pressure and applied voltage to velocities in the 104 ms order. After ejection, the plasma moves into several cone geometries, placed at the end of the electrodes. The conducted studies focus on the Stark-broadening of spectral lines to determine the electron density changes due to the compression. Because of the wide broadening at high electron densities, the well-known Hβ line broadening method is not eligible for cone compressed plasmas. Alternatively, the broadening of the Hα line and a copper line has been used. The achieved electron densities could be increased approximately two orders of magnitude from 1015 cm−3 without the cone to 1017–1018 cm−3 with cone compression.
Boltzmann equation studies on electron swarm parameters in Townsend breakdown of copper vapor plasma using independently assessed electron-collision cross sections
Authors: Yang Wei , Meng Xiaohui , Zhou Qianhong , Dong Zhiwei
Published: March 2019

Electron transport coefficients in copper vapor plasma are calculated both by two-term expansion of electron Boltzmann equation Bolsig+ and tracking the random motion of electrons using Monte Carlo collision code METHES based upon recently evaluated cross section sets. The copper atoms are evaporated from hot electrode during the post-arc phase of vacuum circuit breakers, in which Townsend breakdown between electrode gaps is probable. The electron energy probability function, electron mean energy, flux/transport mobility and diffusion coefficients, as well as Townsend ionization coefficients are shown in reduced fields 10∼1000 Td at a typical vapor temperature 2000 K. The validity of two-term approximation is checked by comparison to well benchmarked METHES code. If the electrode temperature varies between 1500∼2500 K, the influence of vapor temperature on ionization coefficients is about 5% at 200.4 Td, and drops to 0.5% at 493 Td according to Bolsig+ results. Similar to classic gas discharge theory, the Paschen curve is proposed for Townsend breakdown of metal vapor. Using the calculated ionization coefficient and a constant secondary electron yield, the Paschen minimum is determined to be 106∼122 V at a critical value of the product of vapor density and gap length (4.7∼5.7)×1019 m-2. A satisfactory agreement was found with the previously measured ignition voltage between vacuum interrupter contacts after the arcing.
Magnetic field at Ce impurities in La sites of La0.5Ba0.5MnO3 double perovskites
Authors: Bosch-Santos B. , Nascimento N. M. , Saiki M. , Correa E. L. , Sales T. S. N. , Pereira L. F. D. , Cabrera-Pasca G. A. , Saxena R. N. , Schell J. , Carbonari A. W.
Published: March 2019

Due to its rich variety of electromagnetic properties, such as a colossal magnetoresistance, charge and orbital ordering, and metal-insulator transition, the magnetic behavior in La0.5Ba0.5MnO3 double perovskite compounds has been investigated by several techniques, however more experimental data, especially from atomic resolution techniques, are still necessary to understand such complex behavior. In this paper, we have used a nuclear and short-range technique, the Perturbed Angular Correlation (PAC) spectroscopy, to investigate the magnetic hyperfine interaction at the 140Ce and 111Cd probe nuclei as impurities occupying La sites. This double perovskite samples were synthesized by Sol-Gel route. The crystal structure was determined by X-ray diffraction and the analyses showed that this method produced perovskite oxides with cubic structure in Pm-3m space group and the homogeneity was determined by Transmission Electron Microscopy (TEM). The local properties investigated by PAC spectroscopy revealed a ferromagnetic transition temperature above 300 K and a pure antiferromagnetic interaction below 100 K. Moreover, it also indicates an anomalous behavior of the temperature dependence of magnetic hyperfine field at La sites measured with 140Ce probe nuclei, which can be ascribed to the contribution of 4f band of Ce to Magnetic Hyperfine Field (Bhf) at low temperatures due to the increase in its localized character.
Wave breaking in undular bores generated by a moving weir
Authors: Hatland Sondre Dahle , Kalisch Henrik
Published: March 2019

If a weir is dragged through a wave flume, the upstream flow takes the form of an undular bore propagating ahead of the weir. It was found previously in the work of Wilkinson and Banner (“Undular bores,” in 6th Australian Hydraulics and Fluid Mechanics Conference, Adelaide, Australia, 1977) that the leading wave of the undular bore will break if the bore strength given by the ratio of downstream to upstream flow depth exceeds a certain value. In the present work, a Boussinesq system is used to study the situation in a numerical wave tank. It is found that if a convective breaking criterion is used to indicate wave breaking, then the critical bore strength of the numerical model agrees with the experimental value of Wilkinson and Banner up to an error of less than 2%.
A novel wide-range microfluidic dilution device for drug screening
Authors: Wang Cong , Zhao Shikun , Zhao Xianglong , Chen Luan , Tian Zhengan , Chen Xiang , Qin Shengying
Published: March 2019

Microfluidic dilution chip is a crucial approach to perform gradient dilution of experimental samples in many biological investigations. In this study, we developed two serial wide-range dilution chips with dilution rates of 1:1 and 1:4 on the basis of the microfluidic oscillator by designing a series chamber, which was similar to a series circuit. The size of this chamber was adjusted and mixed with the neighboring air chamber to form dilution rates by oscillatory methods. We applied this microfluidic oscillator to estimate cellular kinetics and perform an acute oxidative stress test on Caenorhabditis elegans (C. elegans) in order to further validate their effectiveness. We estimated the kinetic parameters of β-galactosidase, the biocatalyst responsible for the hydrolysis of lactose, and found out that Km was 602 ± 73 μM and kcat was 72 ± 12/s. In addition, our result of the study on acute oxidative stress of C. elegans using this novel chip was consistent with the result using 96-well plates. Overall, we believe that this novel chip can be applied to enzymatic reaction kinetics to evaluate accurately drug screening in bio-nematode models such as C. elegans. In summary, we have provided a novel microfluidic dilution chip that can form a wide range of sample concentration gradients. Our chip may facilitate drug screening, drug toxicology, and environmental toxicology.
Establishing a framework for learning to teach English pronunciation in an Australian TESOL program
Authors: Burri Michael , Baker Amanda , Chen Honglin
Published: March 2019

A substantial number of studies have been conducted in various second language teacher education settings. Yet, evidence about the effectiveness of teacher preparation continues to be debated and research findings about the efficacy of preparing language teachers are still somewhat inconclusive. As a further complication, even though pronunciation has regained some of its prominence in second language teaching, only minimal understanding exists about the preparation of pronunciation instructors in teacher education. The aim of this paper is to address this gap and to advance our understanding of teacher learning by first combining the findings from four research-based articles on learning to teach English pronunciation and then by introducing a new and innovative conceptual framework that reflects effective pronunciation teacher preparation in an Australian context.
Iberian linguistic elements among the black population in New Netherland (1614–1664)
Authors: Dewulf Jeroen
Published: March 2019

Since the slave population in New Netherland (1614–1664) was small compared to that of other Dutch Atlantic colonies such as Curaçao, Dutch Brazil, and Suriname, it has traditionally received little attention by scholars, including creolists. It is, therefore, not well known that traces of Iberian languages can be found among the black population of seventeenth-century Manhattan. While the paucity of sources does not allow us to make any decisive claims with regard to the importance of Spanish and Portuguese for the colony’s black community, this article attempts to reconstruct the language use of this population group on the basis of an analysis of historical sources from New Netherland in a broader Atlantic context.
Trinidadian secondary school students’ attitudes toward accents of Standard English
Authors: Meer Philipp , Westphal Michael , Hänsel Eva Canan , Deuber Dagmar
Published: March 2019

In the anglophone Caribbean, tendencies of endonormative reorientation have been observed in the development of
local standards of English. Situated in the school context, this study adds a language attitude perspective on the question of
whether and to what extent an endonormative standard of English is emerging in the island of Trinidad. In an accent rating study,
803 secondary students were asked to evaluate the accents of Trinidadian, other anglophone Caribbean, American, and British
teachers and to identify their countries of origin. The results indicate that the respondents’ norm orientation is
multidimensional and includes exo- and endonormative influences: first, there is a general coexistence of different standards
since no standard serves as a superordinate norm. Second, there is no clear-cut distinction between exo- and endonormative
accents, but fine-grained differences in the ratings: British and American voices received slightly higher ratings than local
ones, but an American-influenced Trinidadian voice was also highly appreciated. These findings provide some new perspectives for
evolutionary models of World Englishes and new insights for the discussion of standards in Trinidad, the wider anglophone
Caribbean, and other small postcolonial speech communities where different local and global norms interact.
Hacia una ortografía para el chabacano zamboangueño
Authors: Tobar Delgado Eduardo , Fernández Mauro
Published: March 2019

El chabacano zamboangueño goza de una vitalidad en el ámbito oral que no se corresponde con la escasez de textos publicados en esta lengua criolla. Con todo, en los últimos tiempos están aumentando las prácticas escritas en ámbitos como el sistema escolar, los medios audiovisuales o internet. Estas novedades han propiciado el interés por la estandarización de la lengua y el desarrollo de una ortografía estable. Para lograr estos objetivos, los zamboangueños se enfrentan no solo a problemas técnicos sino también ideológicos, ya que el proceso de selección o descarte de rasgos lingüísticos o de grafemas suscita, casi inevitablemente, tensiones antes inexistentes. Este artículo examina la diversidad de prácticas escritas existentes y las propuestas de normativización ortográfica surgidas en los últimos años, prestando atención a los pormenores técnicos y al valor simbólico de las relaciones fonema/grafema.