bluuebunny/crossref_metadata_2025 huggingface dataset:
‘What do you think the aims of doing a practical chemistry course are?’ A comparison of the views of students and teaching staff across three universities
Authors: George-Williams Stephen R. , Ziebell Angela L. , Kitson Russell R. A. , Coppo Paolo , Thompson Christopher D. , Overton Tina L.
Published: January 2018

The aims of teaching laboratories is an important and ever-evolving topic of discussion amongst teaching staff at teaching institutions. It is often assumed that both teaching staff and students are implicitly aware of these aims, although this is rarely tested or measured. This assumption can lead to mismatched beliefs between students and teaching staff and, if not corrected for, could lead to negative learning gains for students and become a source of frustration for teaching staff. In order to measure and identify this gap in a manner that could be readily generalised to other institutions, a single open question – ‘What do you think the aims of doing a practical chemistry course are?’ – was distributed to students and teaching staff at two Australian universities and one UK university. Qualitative analysis of the responses revealed that students and teaching staff held relatively narrow views of teaching laboratories, particularly focusing on aims more in line with expository experiences (e.g. development of practical skills or enhances understanding of theory). Whilst some differences were noted between students at the three institutions, the large amount of similarities in their responses indicated a fairly common perception of laboratory aims. Of the three groups, academics actually held the narrowest view of teaching laboratories, typically neglecting the preparation of students for the workforce or the simple increase in laboratory experience the students could gain. This study highlights gaps between the perceptions of students and teaching staff with regards to laboratory aims alongside revealing that all three groups held relatively simplified views of teaching laboratories.
Study on charge and discharge control strategy of supercapacitor in photovoltaic system
Authors: Yongqing Wei , Xiaofeng Zhao , Fei Yu , Peng Zhu
Published: January 2018

The output power of the photovoltaic (PV) system is random and requires a certain amount of storage capacity to ensure the reliability and continuity of the power supply. The supercapacitor storage can discharge fast, and the energy density is high, so it is an ideal energy storage element. This study has studied the capacitor energy storage system configured in the PV system, by controlling the output power balance between the microgrid and three‐phase inverter to maintain the DC bus voltage stability, and has proposed, respectively, the control strategies of charging and discharging. The simulation results show that when the light or load power changes, the supercapacitor energy storage system can achieve the stability of the DC bus voltage, which verify the validity of the proposed control strategy.
Development status and demand analysis of International Electrotechnical Commission PV standards
Authors: Li Zhen , Qin Xiaodi , Niu Chenhui , Chen Zhilei
Published: January 2018

On the basis of the development status of large‐scale terrestrial photovoltaic (PV) power plants and distributed PV power stations, this study analyses the existing contents and current development of International Electrotechnical Commission standards in the field of solar PV energy system, and gives advice of standard‐writing work in fields of planning, design, construction, technical requirements, test specifications, scheduling, management, maintenance etc.
Voltage stability enhancement by the coordinated operation of OLTCS in the presence of wind turbines using Taguchi method
Authors: Ratra Saurabh , Tiwari Rajive , Niazi Khaleequr Rehman
Published: January 2018

Integration of wind turbines to power systems affects voltage profile and voltage stability, which can be controlled by a coordinated operation of on‐load tap changers (OLTCs). Therefore, coordination and the interaction between the OLTCs and wind turbines (WTs) need to be investigated and taken into account during operational phase. Considering the existing challenges pertaining to integration of WTs to the systems, this study proposes a Taguchi's‐based method to determine size of WTs and optimal tap settings of OLTCs to improve voltage stability of the system. The study also devises a method to identify the critical transformer whose operation is detrimental for voltage stability. The proposed method is tested on IEEE 30‐bus test system.
Locating optimal support generation units based on polynomial approximation of post‐contingency static stability and security regions boundaries
Authors: Qiu Yiwei , Luo Zhihao , Chen Bo , Zhao Qi , Xia Bingqing , Wu Hao , Song Yonghua
Published: January 2018

Post‐contingency support from the generation units is key to the long‐term stability and security of the electrical power system, thus, power companies hope to locate the optimal support generators, which will be planned for improving the ramping abilities to enhance the robustness of the system. To locate the optimal support generators, an extended security constrained optimal power flow model is proposed. Then, as the solution method, a static stability/security region‐based decomposition method is developed. Detailedly, by the polynomial approximation of static stability/security regions using a generalised Galerkin method, the post‐contingency stability and security constraints are transformed into simple polynomial expressions. Thus, the optimisation model for locating the optimal support generators can be easily formulated and solved. The method is verified using a case study in IEEE 118‐bus test system.
Modelling of wind speed correlation based on entropy weighted fuzzy comprehensive evaluation
Authors: Xu Yuqin , Liu Dandan , Zhang Yang
Published: January 2018

With large‐scale grid integration of wind farms, there are various degrees of wind speed correlations between different wind farms. It is significant for economic dispatches and safety analysis of power systems to build an accurate wind speed correlation model. Moreover, the key to precise modelling is to choose an optimised Copula function. Based on single fitting indexes, Copula entropy is introduced as a correlation index. An optimal Copula selection method based on entropy weighted fuzzy comprehensive evaluation is proposed, after which a wind power correlation model is built adopting optimised Copula function. The validity of the proposed method is tested by two wind farms in North China. Finally, Monte Carlo method is adopted to calculate the probabilistic load flow of IEEE30 bus system with multiple wind farms integrated. The results show that the proposed method is reasonable and effective which provides an effective way for economic analysis and dispatches of power system with wind farms.
Maximising wind generation through optimised operation of on‐load tap changing transformers in active distribution networks
Authors: Danzerl Daniel , Gill Simon , Anaya‐Lara Olimpo
Published: January 2018

On‐load tap changing transformers are the most common control device to regulate and maintain distribution network voltage within required limits. Voltage rise issues on the other hand have become a major factor limiting greater penetration of low carbon generators, particularly in weak distribution networks. Here, the voltage rise problem is addressed through the application of optimised set‐point voltage technique that aims to improve network hosting capacity to accommodate high wind penetration. It assesses the effectiveness of the technique on a realistic 289‐node UK generic 11 kV distribution network using time‐series optimal power flow simulations. The results reveal that when the tap changer is operated at the optimised set‐point voltage, it can lead to greater energy yields. It also shows a reduction in the number of tap changing operations when the transformer is operated within the optimised deadband allowing for an improved life‐span and minimum maintenance cost.
Optimal dispatch model considering the bidding uncertainty of wind power in deregulated power system
Authors: Xia Xiang , Lin You , Fang Jianliang , Jiang Wei , He Yingjing , Shang Nan , Ding Yi
Published: January 2018

With the deepen penetration of wind power, wind farms are gradually participating in electricity market. It is essential to consider the bidding uncertainty of wind farms in power system dispatch. This study proposes an optimal real‐time dispatching model considering the bidding risk and the randomness of wind power in deregulated power system. Firstly, the profit‐risk model of wind power is constructed based on the Markowitz theory. Secondly, the uncertainty model of wind generation under different risks can be obtained from the bidding strategy. Then the multi‐state model of wind power is built based on the profit‐risk capacity model. Meanwhile, the uncertainty of wind power generation consists of the natural randomness. Therefore, the multi‐state model of wind power is the equivalence of both the multi‐state model from the bidding strategy and the multi‐state model of the forecast wind power. Lastly, the optimal power flow is adopted to minimise the operating cost of power system based on the above multi‐state models of wind power, as well as the conventional generators and load forecast. The modified IEEE 118‐bus network is used to demonstrate the effectiveness of the proposed model.
Prediction and control of Hopf bifurcation in a large‐scale PV grid‐connected system based on an optimised support vector machine
Authors: Li Sheng , Wei Zhinong , Ma Yanan , Cheng Jielei
Published: January 2018

The unstable Hopf bifurcation (UHB) of a power system generally precedes the saddle‐node bifurcation, so the UHB point can be the system critical point of voltage collapse. However, after the large‐scale photovoltaic (PV) power station is connected to the system, the fluctuation characteristic of PV output can lead to the change of UHB point position and the evaluation process of system voltage stability is also affected. Therefore, according to the feature that the UHB point has the minimum value of hopf bifurcation index (HBI) index, a method for predicting the equilibrium HBI value is proposed based on an optimised support vector machine (SVM) algorithm (including particle swarm optimisation SVM and genetic algorithm optimisation SVM). Once the HBI prediction value of the current operating point (the equilibrium point) is less than or equal to the preset HBI alert value, it is possible to take an emergency load‐shedding measure to remove a small amount of load, and the position of UHB point under maximum PV output is used to set the amount of load‐shedding, so the oscillatory collapse of the load bus voltage caused by a sudden increase of PV output or load fluctuation can be avoided. Taking a large‐scale PV power station access to the classic three‐node system as an example, the prediction and control method is verified. Simulation result shows that the method is simple and practical, as well as suitable for on‐line prediction and control of UHB point in a PV grid‐connected system, which is able to improve the prevention and emergency control capability of the system voltage stability.
Carbon line formation and spectroscopy in O-type stars
Authors: Carneiro L. P. , Puls J. , Hoffmann T. L.
Published: January 2018

Context. The determination of chemical abundances constitutes a fundamental requirement for obtaining a complete picture of a star. Particularly in massive stars, CNO abundances are of prime interest, due to the nuclear CNO-cycle, and various mixing processes which bring these elements to the surface. The precise determination of carbon abundances, together with N and O, is thus a key ingredient for understanding the different phases of stellar evolution.

Aims. We aim to enable a reliable carbon spectroscopy for our unified non-LTE atmosphere code FASTWIND.

Methods. We have developed a new carbon model atom including C II/III/IV/V, and we discuss specific problems related to carbon spectroscopy in O-type stars. We describe different tests we have performed to examine the reliability of our implementation, and investigate which mechanisms influence the carbon ionization balance. By comparing with high-resolution spectra from six O-type stars, we verified to what extent observational constraints can be reproduced by our new carbon line synthesis.

Results. Carbon lines are even more sensitive to a variation of Teff, log g, and Ṁ, than hydrogen and helium lines. We are able to reproduce most of the observed lines from our stellar sample, and to estimate those specific carbon abundances which bring the lines from different ions into agreement (three stages in parallel for cool objects, two for intermediate O-types). For hot dwarfs and supergiants earlier than O7, X-rays from wind-embedded shocks can have an impact on the synthesized line strengths, particularly for C IV, potentially affecting the abundance determination. Dielectronic recombination has a significant impact on the ionization balance in the wind.

Conclusions. We demonstrate our capability to derive realistic carbon abundances by means of FASTWIND, using our recently developed model atom. We find that complex effects can have a strong influence on the carbon ionization balance in hot stars. For a further understanding, the UV range needs to be explored as well. By means of detailed and available nitrogen and oxygen model atoms, we will be able to perform a complete CNO abundance analysis for larger samples of massive stars, and to provide constraints on corresponding evolutionary models and aspects.
L’émergence de nouvelles coopératives semencières au Sénégal – Analyse de l’impact de la recherche-développement sur l’arachide de 1999 à 2016
Authors: Clavel Danièle , Gaye Matar
Published: January 2018

Cet article analyse un processus d’innovation dans la filière arachide au Sénégal entre 1999 et 2016. L’accent porte sur la mise en évidence des facteurs décisifs dans l’émergence d’un nouveau réseau de coopératives semencières au Sénégal sous l’impulsion de l’organisation de producteurs Asprodeb. L’analyse est basée sur la théorie du changement qui accorde une place importante aux relations entre les innovations techniques et leur contexte politique et social. Nous concluons que trois facteurs ont été déterminants dans les changements observés : (1) une opération pilote de recherche et développement réunissant la recherche, l’organisation de producteurs et les producteurs de la commune de Paoskoto, lieu initial de la traduction des résultats de recherche en réalisations concrètes, (2) le renforcement et la diversification du partenariat entre acteurs de la filière, en particulier du secteur semences et (3) le renforcement des capacités conduisant à une professionnalisation des producteurs et productrices adhérents des coopératives. Au-delà des succès obtenus, l’étude a permis d’identifier un risque de fragilisation du système coopératif si l’expertise semencière développée par l’Asprodeb n’est mobilisée qu’à des fins commerciales. Par ailleurs, cette analyse d’impact qualitative, participative et réflexive a permis un éclairage du rôle, souvent invisible, tenu par les chercheurs, qui, opérant en contexte, ont facilité les processus d’innovation et les connexions entre acteurs.
Homonymous Hemianopia in Children and Adolescents: An MRI Study
Authors: Trauzettel-Klosinski Susanne , Krumm Anna , Küster Stephan , Ivanov Iliya , Cordey Angelika , Gehrlich Claudia , Staudt Martin , Haaga Manja
Published: January 2018

Aim Diagnosing homonymous hemianopia (HH) in children can be difficult due to inability to comply with perimetry. Therefore, HH can often only be suspected by magnetic resonance imaging (MRI) showing lesions to the retrochiasmatic visual pathways. The aim of our retrospective observational cross-sectional study was to improve the radiologic detection of HH.

Methods MRIs of 21 subjects (5–17 years old) with ophthalmologically confirmed HH (14 complete, 7 incomplete hemianopias) were analyzed. In addition, we asked four questions looking at everyday problems possibly related to the HH. The questions asked for (1) problems in avoiding objects/people, (2) bumping into objects/people, (3) difficulties in judging stairs, and (4) difficulties in grasping objects.

Results We found neuroanatomical correlates of the HH in all 21 participants, with the optic radiation being involved in almost all participants (20/21). Everyday problems possibly related to the HH were reported for all nine patients with postneonatally acquired complete hemianopias. In contrast, no such problems were reported for seven patients with incomplete HH (7/7) and for 3/5 patients with complete hemianopias due to pre-, peri- or neonatally acquired brain lesions.

Interpretation A dedicated radiologic analysis of the retrochiasmatic optic pathway should routinely be performed in children with brain lesions to identify children with HH. Early onset and incomplete HH are predictors for successful compensation.
Treatment Outcomes for Right-Sided Endocarditis in Intravenous Drug Users: A Systematic Review and Analysis of Outcomes in a Tertiary Centre
Authors: Magsino Karen , Sanjanwala Rohan , Hiebert Brett , Rothney Janet , Manji Rizwan , Arora Rakesh , Shah Pallav
Published: January 2018

Background The increasing prevalence of intravenous drug users (IVDU) has resulted in higher incidence of right-sided infective endocarditis (RSIE). However, treatment guidelines for RSIE in IVDU are not well defined. The aim is to evaluate efficacy of different treatment strategies in reducing mortality and to describe treatment outcomes.

Methods We systematically reviewed the literature using PubMed, Cochrane, CENTRAL, OvidEMBASE, Web of Science, and Medline databases to include prospective studies that compare mortality rates among IVDU with RSIE receiving isolated medical treatment versus those receiving medical–surgical treatment. In conjunction, analysis of 27 RSIE patients (including IVDU) treated at authors' institution was done to supplement the findings. Kaplan–Meier survival rates following hospital admission and cumulative incidence estimates for hospital re-admission were obtained.

Results A total of nine studies (all with low or marginal risk of bias) met inclusion criteria. The prevalence of RSIE among IVDU with infective endocarditis varied from 34% to 100%. Seven studies compared medical versus medical–surgical therapy with less than 30% needing surgery. Mortality was higher in patients receiving surgical therapy. There were 27 RSIE (16 non-IVDU and 11 IVDU) analyzed at the authors' institution. Survival at 30 days, 1 year, and 3 years were 89%, 82%, and 78%, respectively, and repeat hospitalization for recurrent endocarditis were 8%, 17%, and 23%, respectively.

Conclusions There is paucity around optimal RSIE management strategy for IVDU that can decrease mortality. Surgical management of RSIE may be associated with increased mortality over medical management mainly due to advanced surgical indications.
The Impact of Migration Background on the Health Outcomes of Preschool Children: Linking a Cross-Sectional Survey to the School Entrance Health Examination Database in Bavaria, Germany
Authors: Thi Thu , Heißenhuber Annette , Schneider Thomas , Schulz Rebekka , Herr Caroline , Nennstiel-Ratzel Uta , Hölscher Gabriele
Published: January 2018

Aim of the study This study investigated the impact of migration background on the health outcomes of preschool children from families of various social status levels.

Methods During the school entrance health examination (Schuleingangsuntersuchung (SEU)) from October 2012 to August 2013, the parents of 5052 preschool children (62% response rate) participated in a cross-sectional health survey within the framework of health-monitoring units (Gesundheits-Monitoring-Einheiten (GME)) in Bavaria, Germany. They were handed a self-administered questionnaire with questions relating to the language spoken at home and other socio-demographic characteristics. By applying the record linkage method, 3747 participants were correctly linked to the corresponding data of the SEU. Based on the merged dataset, 4 definitions of migration background were explored regarding demographic indicators, the parents’ mother tongue, and the language spoken at home. The association between migration background and health outcomes of preschool children was analyzed using multivariable logistic regression models separately. The risk estimates were presented for the study population and stratified into high, medium, and low social status. The models were repeated for each of the 4 migration background variables.

Results The results show significant associations between migration background and health outcomes of preschool children (except in pronunciation). A migration background had the strongest impact on the development of word/sentence formation disorder. Compared to non-migrant preschool children, migrant children had twice the chances for full vaccination coverage (OR [95% CI]: 2.4 [1.9–3.1]) but only half the chance to participate in all health examinations from U1 to U9 (0.5 [0.4–0.6]). These children were also at two-fold increased risk to be overweight/obese (2.2 [1.7–2.8]). Moreover, preschool children with double-sided migration from medium social status families faced the highest risk for word/sentence formation disorder (9.5 [5.6–16.1] with SEU definition and 23.3 [10.3–52.6] with GME definition of a migration background).

Conclusions Future prevention programs at the preschool level should focus on children with double-sided migration from medium social status families. With respect to social and cultural integration, the definition of migration background based on the language spoken at home should be appropriate for future SEUs.
Kampō in der Gastroenterologie
Authors: Ahrens Tobias
Published: January 2018

Die Kampō-Medizin ist eine mehr als 1000 Jahre alte Form der japanischen Phytotherapie, die auf pragmatische Art die Erkenntnisse der wissenschaftlich fundierten Medizin mit traditionellen Konzepten wie der Bauchdeckendiagnostik verbindet. Kampō ist heute fest im japanischen Gesundheitssystem verankert und wird von ca. 83,5 % der praktizierenden Ärzte dort genutzt, wobei die meisten Anwender Kampō-Rezepturen ausgehend von wissenschaftlichen Wirksamkeitsbelegen bzw. ICD-Diagnosen verschreiben. Grundlage dafür ist eine überschaubare Anzahl standardisierter Rezepturen, die überwiegend als Trockenextrakt in Granulatform eingenommen werden.

Anwendungsmöglichkeiten bestehen für eine Vielzahl von akuten und chronischen Beschwerden, wobei neben der Studienlage die Konstitution und das individuelle Beschwerdemuster des Patienten eine wichtige Rolle für die Auswahl der passenden Rezeptur spielen. Rikkunshi tō, hange shashin tō und keishi ka shakuyaku tō sind drei Kampō-Rezepturen, für deren Anwendung es bei dyspeptischen Beschwerden, der Reduktion Irinotecan-vermittelter Diarrhöen und dem Reizdarmsyndrom vom Diarrhö-Typ vielversprechende wissenschaftliche Wirksamkeitsbelege gibt. Nachdem Herr Kutcha bereits 2014 in der Zeitschrift für Phytotherapie sehr umfassend die Geschichte der Kampō-Medizin dargestellt hat, möchte ich nur kurz auf allgemeine Aspekte wie die historische Entwicklung eingehen und die spezifischen Anwendungsmodalitäten und therapeutischen Möglichkeiten bei gastrointestinalen Erkrankungen in den Vordergrund stellen.
Zugewanderte Ärzte: Chancen und Herausforderungen im deutschen Klinikalltag
Authors: Hohmann Isabel , Glaesmer Heide , Nesterko Yuriy
Published: January 2018

Hintergrund und Ziel Es besteht ein Bedarf an zugewanderten Ärzten in der Versorgungsstruktur der Bundesrepublik Deutschland. Die Situation der betreffenden Ärzte ist bisher weitestgehend unerforscht. Im Rahmen einer explorativen Pilotstudie wurden Stressoren und Ressourcen von zugewanderten Ärzten im Hinblick auf ihre migrationsbedingten Erfahrungen an deutschen Kliniken und im medizinischen Team erforscht.

Methodik Im Rahmen einer qualitativen Untersuchung wurden im Zeitraum von Juli bis September 2014 acht problemzentrierte Interviews mit zugewanderten Ärztinnen und Ärzten durchgeführt und analysiert. Die Befragten stammten aus dem EU-In- und Ausland und waren seit 1,0–4,5 Jahren in verschiedenen Kliniken in Deutschland tätig.

Ergebnisse Stressoren und Herausforderungen ergaben sich im Bereich der deutschen Sprachkenntnisse, der medizinischen Kompetenzen, der Zusammenarbeit im Team sowie in Bezug auf die Arbeit im neuen Gesundheitssystem. Diskriminierung durch Kollegen und Patienten stellte eine besondere Belastung dar. Währenddessen verfügten die zugewanderten Ärzte über Ressourcen sprachlich-kommunikativer, medizinischer, sozialer und organisationaler Art.

Diskussion Die Ergebnisse verdeutlichen die besondere Beanspruchung von zugewanderten Ärzten. Künftige Forschung sollte migrationsbedingte Belastungs- und Entlastungspotenziale von zugewanderten Ärzten mittels quantitativer Methodik auf eine breitere Basis stellen und im Sinne eines Mehrperspektiven-Ansatzes deutsche Kollegen und Patienten einbeziehen.
MicroRNAs and Target Genes in Pituitary Adenomas
Authors: Feng Yajuan , Mao Zhi-gang , Wang Xin , Du Qiu , Jian Mengyao , Zhu Dimin , Xiao Zheng , Wang Hai-jun , Zhu Yong-hong
Published: January 2018

Pituitary adenomas account for the top three primary intracranial tumors in terms of total incidence rates. The clinical symptoms presented by the disease are often characterized by a series of systemic endocrine disorders, severe occupational lesions, and even some malignant features, and therefore early diagnosis and predicting recurrence would be instructive for clinical treatment of pituitary adenomas. An increasing number of specific microRNA (miRNA) expression signatures have been identified in pituitary, and miRNAs are related with the pituitary tumorigenesis, dysfunction, neurodegeneration, and metastatic non-functioning pituitary carcinoma. Here, this paper reviews the effects of aberrant miRNA expression in human pituitary adenomas and summarizes some corresponding target genes and biological significance over the last 7 years (2010–2017).
Percutaneous-endoscopic rendezvous procedure for the management of bile duct injuries after cholecystectomy: short- and long-term outcomes
Authors: Schreuder Anne , Booij Klaske , de Reuver Philip , van Delden Otto , van Lienden Krijn , Besselink Marc , Busch Olivier , Gouma Dirk , Rauws Erik , van Gulik Thomas
Published: January 2018

Background Bile duct injury (BDI) remains a daunting complication of laparoscopic cholecystectomy. In patients with complex BDI, a percutaneous-endoscopic rendezvous procedure may be required to establish bile duct continuity. The aim of this study was to assess short- and long-term outcomes of the rendezvous procedure.

Methods All consecutive patients with BDI referred to our tertiary referral center between 1995 and 2016 were analyzed. A rendezvous procedure was performed when endoscopic or radiologic intervention failed, and when deemed feasible by a dedicated multidisciplinary team including hepatopancreaticobiliary surgeons, gastrointestinal endoscopists, and interventional radiologists. Classification of BDI, technical success of the rendezvous procedure, procedure-related adverse events, and outcomes were assessed.

Results Among a total of 812 patients, rendezvous was performed in 47 (6 %), 31 (66 %) of whom were diagnosed with complete transection of the bile duct (Amsterdam type D/Strasberg type E injury). The primary success rate of rendezvous was 94 % (44 /47 patients). Overall morbidity was 18 % (10 /55 procedures). No life-threatening adverse events or 90-day mortality occurred. After a median follow-up of 40 months (interquartile range 23 – 54 months), rendezvous was the final successful treatment in 26 /47 patients (55 %). In 14 /47 patients (30 %), rendezvous acted as a bridge to surgery, with hepaticojejunostomy being chosen either primarily or secondarily to treat refractory or relapsing stenosis.

Conclusions In experienced hands, rendezvous was a safe procedure, with a long-term success rate of 55 %. When endoscopic or transhepatic interventions fail to restore bile duct continuity in patients with BDI, rendezvous should be considered, either as definitive treatment or as a bridge to elective surgery.
Innovation und Evidenz im Fokus
Authors: Kraft Karin , Stange Rainer , Meng Günter
Published: January 2018

Der diesjährige nationale Kongress der GPT fand vom 28. bis 30.9.2017 unter dem Motto „Von der Innovation zur Evidenz“ im PharmaCampus (Institut für Pharmazeutische Biologie und Phytochemie) der Westfälischen Wilhelms-Universität Münster statt.
Kohn-Sham potentials from electron densities using a matrix representation within finite atomic orbital basis sets
Authors: Zhang Xing , Carter Emily A.
Published: January 2018

We revisit the static response function-based Kohn-Sham (KS) inversion procedure for determining the KS effective potential that corresponds to a given target electron density within finite atomic orbital basis sets. Instead of expanding the potential in an auxiliary basis set, we directly update the potential in its matrix representation. Through numerical examples, we show that the reconstructed density rapidly converges to the target density. Preliminary results are presented to illustrate the possibility of obtaining a local potential in real space from the optimized potential in its matrix representation. We have further applied this matrix-based KS inversion approach to density functional embedding theory. A proof-of-concept study of a solvated proton transfer reaction demonstrates the method’s promise.
Two-component relativistic coupled-cluster methods using mean-field spin-orbit integrals
Authors: Liu Junzi , Shen Yue , Asthana Ayush , Cheng Lan
Published: January 2018

A novel implementation of the two-component spin-orbit (SO) coupled-cluster singles and doubles (CCSD) method and the CCSD augmented with the perturbative inclusion of triple excitations [CCSD(T)] method using mean-field SO integrals is reported. The new formulation of SO-CCSD(T) features an atomic-orbital-based algorithm for the particle-particle ladder term in the CCSD equation, which not only removes the computational bottleneck associated with the large molecular-orbital integral file but also accelerates the evaluation of the particle-particle ladder term by around a factor of 4 by taking advantage of the spin-free nature of the instantaneous electron-electron Coulomb interaction. Benchmark calculations of the SO splittings for the thallium atom and a set of diatomic 2Π radicals as well as of the bond lengths and harmonic frequencies for a set of closed-shell diatomic molecules are presented. The basis-set and core-correlation effects in the calculations of these properties have been carefully analyzed.
Optimal cogeneration and scheduling of hybrid hydro-thermal-wind-solar system incorporating energy storage systems
Authors: Hemmati Reza
Published: January 2018

This paper optimizes cogeneration of a hydro-thermal-wind-solar system. In the proposed hybrid system, the energy storage systems are also incorporated to smooth out the fluctuations of renewable energies. The uncertainties of wind and solar powers are included, and stochastic programming is adopted to deal with the uncertainties. The hydro system comprises two cascade reservoirs. The optimal scheduling of both reservoirs is presented, and the electricity generated by each reservoir is optimized. The optimal scheduling of thermal unit is also determined. The optimal location, capacity, power, and charging-discharging pattern are determined for battery energy storage systems. The simulations are carried out using an IEEE 69-bus distribution network, and the model is implemented in GAMS software and solved as a mixed integer linear programming. The objective of the problem is to minimize energy cost in the network. The results demonstrate that the proposed stochastic model can successfully optimize cogeneration of hydro-thermal-wind-solar system. The planning moreover optimally utilizes energy storage systems for damping the fluctuations of renewable energies and minimizing energy cost.
The impacts of urbanization on Chinese households' energy consumption: An energy input-output analysis
Authors: Liu Hongtao , Lei Juanjuan
Published: January 2018

Since China's economic reforms and opening-up policy in 1980, China has experienced significant urbanization. This rapid urbanization has stimulated the growth of energy consumption. To investigate the impacts of urbanization on Chinese households' energy consumption, this paper analyzed the changes in households' direct energy consumption (DEC) and calculated households' indirect energy consumption (IEC) based on an energy input-output model. By applying an input-output structure decomposition analysis model, this paper quantitatively measured the impacts of urbanization on the direct and indirect energy consumption of households in China. We found that the amount of China's urban households' DEC gradually increased from 48.7 million tons of oil equivalent to 185.2 million tons of oil equivalent. In 2012, the proportion of coal products in urban households' DEC decreased from 91.4% in 1980 to 24.3%, while the proportion of petroleum products, natural gas, and electricity in urban households' DEC increased. During 1980 to 2012, China's rural households' DEC increased from 36.7 million tons of oil equivalent to 121.5 million tons of oil equivalent. However, the proportion of coal products was still greater than 50% in 2012. Chinese households' IEC increased from 302.8 million tons of oil equivalent in 1987 to 769.9 million tons of oil equivalent in 2010. In addition, China's urban households' IEC had a faster growth rate than China's rural households' IEC. Urban households' IEC increased from 139.0 million tons in 1987 to 599.8 million tons in 2010, while rural households' IEC fluctuated during the same period, with 163.8 million tons in 1987, 132.2 million tons in 2000, and 170.1 million tons in 2010. Among the impact factors of households' DEC, which include the population, urbanization rate, urban/rural households' DEC per capita and urban/rural households' DEC structure, China's total population has a positive effect on households' DEC growth. The urbanization rate is the other important factor constantly stimulating China's households' DEC growth. For households' IEC, the urbanization rate and per capita consumption had positive effects on the increase in households' IEC. Except for the period from 2002 to 2005, direct energy intensity had a negative effect on the increase in households' IEC in other periods. The Leontief effect on households' IEC was positive from 2000 to 2005 and negative in other subperiods. The results indicate that China needs to integrate energy efficiency, ecological conservation, and social fairness in its “new-type urbanization” planning. Green lifestyles within the household and low-carbon city construction should be encouraged.
Brian Herbert Kay 1944–2017
Authors: Good Michael F. , Ritchie Scott A. , McGinn Darryl , Russell Richard C.
Published: January 2018

Brian Kaywas a renowned entomologist and arbovirologistwhoworked in academia and with local and international governments to make major and lasting improvements in public health. Particular highlights were the first ever elimination of a saltmarsh mosquito in the world and elimination of dengue from many hamlets and villages in Vietnam. He is also remembered for the development of the careers of many young researchers in Australia and overseas. When thinking of Brian Kay, three things come to mind immediately. First, Brian was a great character–a man of fun and passion and always good to be around. He had a great cheeky smile. Second, Brian was deeply committed to the careers and well-being of those around him–exemplified no better than how he acted so caringly for the Queensland Institute of Medical Research (QIMR) staff when he served for several years as Chairman of the QIMR Staff Association; and third, Brian was an outstanding entomologist, biologist, scientist. Here, we give a little history of his background and attempt to distil a few of Brian's many scientific achievements and paint a picture of a man who was greatly admired and loved by those who worked alongside him in various parts of the world, but predominantly in Australia and the Asia Pacific Region.
Lawrence Walter Nichol 1935–2015
Authors: Jeffrey Peter D. , Winzor Donald J. , Kuchel Philip W.
Published: January 2018

Lawrence (Laurie) Walter Nichol FAA was Vice Chancellor of the Australian National University (ANU) from 1988 to 1993, and before that, of the University of New England (UNE) from 1985 to 1988. His independent academic career began in 1963 at the ANU as a Research Fellow in the Department of Physical Biochemistry in the John Curtin School of Medical Research (JCSMR). The department was headed by Professor Alexander (Sandy) G. Ogston FRS. Thus, Laurie's career finally circled back, after overseas sabbaticals and other appointments at Australian universities, to the ANU.
Managing invasive plants on sub-Antarctic Macquarie Island
Authors: Sindel Brian M. , Kristiansen Paul E. , Wilson Susan C. , Shaw Justine D. , Williams Laura K.
Published: January 2018

The Antarctic region is one of the most inhospitable frontiers on earth for weed invasion. On Australia’s world heritage sub-Antarctic Macquarie Island only three species of invasive weeds are well established (Poa annua L., Stellaria media (L.) Vill. and Cerastium fontanum Baumg.), although isolated occurrences of other species have been found and removed. These weed species are believed to have initially been introduced through human activity, a threat which is likely to increase, although strict biosecurity is in place. All three weeds are palatable and may have been suppressed to some extent by pest herbivore (rabbit) grazing. Given the high conservation value of Macquarie Island and threats to ecosystem structure and function from weed proliferation following rabbit eradication, well targeted invasive plant control management strategies are vital. We propose that a successful restoration program for Australia’s most southerly rangeland ecosystem should integrate both control of non-native plants as well as non-native herbivores. Of the non-native plants, S. media may most easily be managed, if not eradicated, because of its more limited distribution. Little, however, is known about the soil seed bank or population dynamics after rabbit eradication, nor the effect of herbicides and non-chemical control methods in cold conditions. A current research project on this non-grass species is helping to fill these knowledge gaps, complementing and building on data collected in an earlier project on the ecology and control of the more widespread invasive grass, P. annua. With an interest in off-target herbicide impacts, our work also includes a study of the movement and fate of herbicides in the cold climate Macquarie Island soils. Research in such a remote, cold, wet and windy place presents a range of logistical challenges. Nevertheless, outcomes are informing the development of effective, low-impact control or eradication options for sub-Antarctic weeds.
Full molecular trajectories of RNA polymerase at single base-pair resolution
Authors: Righini Maurizio , Lee Antony , Cañari-Chumpitaz Cristhian , Lionberger Troy , Gabizon Ronen , Coello Yves , Tinoco Ignacio , Bustamante Carlos
Published: January 2018

Significance

Optical tweezers enable scientists to follow the dynamics of molecular motors at high resolution. The ability to discern a motor’s discrete steps reveals important insights on its operation. Some motors operate at the scale of angstroms, rendering the observation of their steps extremely challenging. In some cases, such small steps have been observed sporadically; however, the full molecular trajectories of steps and intervals between steps remain elusive due to instrumental noise. Here, we eliminate the main source of noise of most high-resolution dual-trap optical tweezers and developed both a single-molecule assay and a self-learning algorithm to uncover the full trajectories of such a motor: RNA polymerase. Using this method, a whole new set of experiments becomes possible.
The sociolinguistic meanings of syllable contraction in
Chinese
Authors: Xu Chenchen , Mao Lingfeng
Published: January 2018

Syllable contraction has been observed in many modern Chinese varieties,
including Mandarin. Public opinion of syllable contraction, especially some
stereotyped contracted words, tends to associate it with a southern (especially
Taiwanese) accent. Gendered social meanings are often attached to it as well.
This paper investigates Mandarin syllable contraction using Prestonian
perceptual mapping techniques, graphical aggregation, and quantitative
comparisons. The results of the mapping tasks suggest that participants’ beliefs
about the location and gender of contraction users are generally in line with
the public opinions observed in qualitative analyses of media discourses.
However, an analysis of map responses in terms of respondents’ region of origin
and gender uncovers nuanced contrasts along gendered and regional lines.
Northern respondents (judges) had a negative attitude toward southern
contraction but a positive opinion toward northern contraction, while southern
judges viewed syllable contraction positively regardless of region. Female
judges viewed female contraction users positively and male users negatively, but
male judges had a strongly negative opinion of only the male users. Region and
gender intertwine with each other and constitute the sociolinguistic meanings of
Chinese syllable contraction that involve both the user and perceiver. In this
way, the study uncovers new perceptual perspectives on the sociolinguistic
meaning of a less commonly studied variable in a less commonly studied
language.
The future of ‘future’
Authors: Ghafar Samar Reza , Bhatia Tej
Published: January 2018

Bybee et al. (1994)claimed that grammatical-types like past and future have similar paths of development cross-linguistically. Following another line of research,Poplack (2011),Poplack and Tagliamonte (2000)andWalker et al. (2004)explored the grammaticalization of periphrastic ‘go-future’ in English, French, and Spanish from a variationist perspective and have come to the same conclusion. In this study we explore whether a new Persian future marker, MI_KHA: ‘want/will/going to’, which is gaining ground in this language, can be an instance of the grammatical-types mentioned above, and follows the same path of variation and change as that of English and French. Eight-hundred and one future-referring utterances were collected from natural conversations among Persian native speakers and subjected to variable rule analysis to discover the factors conditioning their use and variation. The findings suggest that the Persian MI_KHA: is not only conditioned by linguistic factors, it also most likely follows a path of development similar to English and French.
Singaporean internet chit chat compared to informal spoken language*
Authors: Deuber Dagmar , Leimgruber Jakob R. E. , Sand Andrea
Published: January 2018

This paper compares data from a Singaporean chit chat forum to informal spoken data. We first perform a qualitative analysis of text samples in a framework of indexicality. Then we present quantitative findings for two (sets of) features each of the contact variety Singlish (particles, thekena-passive) and spoken English in general (discourse markers, contractions). For the former some similarities are observed but we also find that the forum contributors tend to be creative and innovative in their choice of particles. In this connection we argue that they index specific subgroup identities and further point out that Singlish is a rather flexible set of resources. Our findings differ from those of previous research on Jamaican Creole as used in an internet forum, thus showing that the use of contact varieties in computer-mediated communication can take different forms. The general features of spoken English are used comparatively less in the forum data, indicating that using Singlish features in writing is not tantamount to writing down spoken language. Moreover, we draw attention to features of computer-mediated communication in in the chit chat forum data. Finally we discuss implications in terms of the Dynamic Model of the evolution of Postcolonial Englishes (Schneider 2007).
The effects of transliterations, thematic organization, and working memory on adult L2 vocabulary learning
Authors: Tseng Alison M. , Doppelt Martin C. , Tokowicz Natasha
Published: January 2018

We examine how L2 vocabulary learning is affected by the information provided to the learner during training, organization of the to-be-learned vocabulary, and working memory capacity of the learner. Native English speakers were taught Arabic vocabulary in seven sessions, during which they heard L1 (English)-L2 (Arabic) translation pairs. Training was manipulated between participants by crossing the presence vs. absence of a transliteration and thematic vs. random organization of vocabulary. Session, working memory capacity, transliteration condition, and organization condition interacted in English-Arabic translation accuracy. Participants with lower working memory capacity performed best in the transliteration-thematic organization condition, whereas participants with higher working memory performed best in the transliteration-random organization and no transliteration-thematic organization conditions. Translation RT and free recall were not related to working memory, and were best in the transliteration conditions. Results suggest that adult L2 vocabulary learning is aided by exploiting well-established spelling-sound connections to improve L2 lexical representations.
Grammatical gender processing in L2 speakers of Spanish
Authors: Halberstadt Lauren , Valdés Kroff Jorge R. , Dussias Paola E.
Published: January 2018

Recent findings indicate that native speakers (L1) use grammatical gender marking on articles to facilitate the processing of upcoming nouns (e.g., Lew-Williams & Fernald, 2007; Dussias, Valdés Kroff, Guzzardo Tamargo, & Gerfen, 2013). Conversely, adult second language (L2) learners for whom grammatical gender is absent in their first language appear to need near-native proficiency to behave like native speakers (Dussias et al., 2013; Hopp, 2013). The question addressed here is whether sensitivity to grammatical gender in L2 learners of Spanish is modulated by the cognate status of nouns due to their heightened parallel orthographic, phonological, morpho-syntactic and semantic activation. Additionally, the role of transparent and non-transparent word-final gender marking cues was examined because past studies have shown that native speakers of Spanish are sensitive to differences in gender transparency (Caffarra, Janssen, & Barber, 2014). Participants were English learners of Spanish and Spanish monolingual speakers. Data were collected using the visual world paradigm. Participants saw 2-picture visual scenes in which objects either matched in gender (same-gender trials) or mismatched (different-gender trials). Targets were embedded in the preamble Encuentra el/la ___ ‘Find the ___’. The monolingual group displayed an anticipatory effect on different gender trials, replicating past studies that show that native speakers use grammatical gender information encoded in prenominal modifiers predictively. The learners were able to use gender information on the articles to facilitate processing, but only when the nouns had gender endings that were transparent. Cognate status did not confer an advantage during grammatical gender processing.