bluuebunny/crossref_metadata_2025_split huggingface dataset:
Moon, Mars and Mundus: primary school children discover the nature and science of planet Earth from experimentation and extra-terrestrial perspectives
Authors: Kleinhans M.G. , Verkade A.J. , van Wessel T. , Bastings M.A.S. , Marra W.A. , van Gog T. , van Westrenen W. , Reichwein M. 
Published: February 2015

AbstractLike earth and planetary scientists, most children are curious about the world, the solar system and the rest of the universe. However, for various reasons primary schools emphasise language and calculus rather than natural sciences. When science is taught, examination systems often favour knowledge of the ‘right’ answer over the process of investigation and logical reasoning towards that answer. In order to continue to spark children's curiosity and their motivation to learn and discover, science education hubs at universities and science museums could collaborate more with schools and teachers, and are beginning to do so. The objective of this position paper is to report on recent experiences in earth and planetary science education for pupils in primary and secondary education, to provide examples and inspiration for scientists. We report three examples of initiation and consolidation of science education in primary schools in the Netherlands: (1) a focus on asking questions and seeking information to reason towards the answer, initiated with a classroom game, Expedition Mundus, (2) bringing pupils and teachers together outside their school in the science museum to gain confidence and self-efficacy, and (3) having children ask their own questions and do their own research guided by the empirical cycle, for example on experimentation on sandbox scale models of channels and crater lake deltas as found on Mars. The focus on other planets, fictitious and real, stimulates pupils to ask questions about planet Earth. Finally, we argue that involvement of more scientists in science education would not only benefit primary and secondary schools and future students but also university education and science communication with society.
Effects of a food-based intervention on markers of micronutrient status among Indian women of low socio-economic status
Authors: Kehoe Sarah H. , Chopra Harsha , Sahariah Sirazul A. , Bhat Dattatray , Munshi Renuka P. , Panchal Falguni , Young Stephen , Brown Nick , Tarwande Dnyaneshwar , Gandhi Meera , Margetts Barrie M. , Potdar Ramesh D. , Fall Caroline H. D. 
Published: February 2015

Intakes of micronutrient-rich foods are low among Indian women of reproductive age. We investigated whether consumption of a food-based micronutrient-rich snack increased markers of blood micronutrient concentrations when compared with a control snack. Non-pregnant women (n222) aged 14–35 years living in a Mumbai slum were randomised to receive a treatment snack (containing green leafy vegetables, dried fruit and whole milk powder), or a control snack containing foods of low micronutrient content such as wheat flour, potato and tapioca. The snacks were consumed under observation 6 d per week for 12 weeks, compliance was recorded, and blood was collected at 0 and 12 weeks. Food-frequency data were collected at both time points. Compliance (defined as the proportion of women who consumed ≥ 3 snacks/week) was >85 % in both groups. We assessed the effects of group allocation on 12-week nutrient concentrations using ANCOVA models with respective 0-week concentrations, BMI, compliance, standard of living, fruit and green leafy vegetable consumption and use of synthetic nutrients as covariates. The treatment snack significantly increased β-carotene concentrations (treatment effect: 47·1 nmol/l, 95 % CI 6·5, 87·7). There was no effect of group allocation on concentrations of ferritin, retinol, ascorbate, folate or vitamin B12. The present study shows that locally sourced foods can be made into acceptable snacks that may increase serum β-carotene concentrations among women of reproductive age. However, no increase in circulating concentrations of the other nutrients measured was observed.
On some questions related to Koethe's nil ideal problem
Authors: Chebotar M. A. , Lee P.-H. , Puczyłowski E. R. 
Published: February 2015

AbstractWe study properties of two-sided and one-sided ideals of A-rings, i.e. rings that are sums of their nil left ideals. We show that the question as to whether one-sided ideals of A-rings are again A-rings is equivalent to the famous Koethe problem. We also obtain some results on another related open problem that asks whether annihilators of elements of non-zero A-rings are non-zero.
INFLUENCE OF ALUMINIUM ON GROWTH, MINERAL NUTRITION AND ORGANIC ACID EXUDATION OF RAMBUTAN (Nephelium lappaceum)
Authors: PÉREZ-ALMODÓVAR DELVIS , GOENAGA RICARDO 
Published: February 2015

SUMMARYA randomized complete block design experiment with six aluminium (Al) concentrations was carried out to evaluate the effect of Al on nutrient content, plant growth, dry matter production and Al-induced organic acid exudation in rambutan (Nephelium lappaceum). One rambutan cultivar was grown in nutrient solution at pH 4.0 with (1.0, 2.3, 4.1, 6.7 and 10.2 mM Al) and without Al. The results of this study confirms that this crop is highly tolerant to Al in the rhizosphere as evidenced by: (1) a root tolerance index (RTI) of 0.85 when plant roots are exposed to Al concentrations as high as 3.5 mM; (2) root tissue Al concentrations as high as 6800 mg g−1and the plants survived; (3) number of leaves, plant height and stem diameter being little affected when plants were grown at an Al concentration in the soil solution as high as 3.5 mM; (4) although plants exhibited leaf abscission, they were able to tolerate Al concentrations in the nutrient solution as high as 10.2 mM during the experimental period. No evidence of organic acid exudation was found in this study. Accumulation of Al in leaves, stems and roots suggests the existence of an Al-sequestration mechanism in rambutan which may involve an Al-ligand complex which translocates from roots to shoots, where it may accumulate in leaf vacuoles.
DIVERSITY IN SMALLHOLDER FARMS GROWING COFFEE AND THEIR USE OF RECOMMENDED COFFEE MANAGEMENT PRACTICES IN UGANDA
Authors: BONGERS GHISLAINE , FLESKENS LUUK , VAN DE VEN GERRIE , MUKASA DAVID , GILLER KEN , VAN ASTEN PIET 
Published: February 2015

SUMMARYMany smallholder farm systems in Uganda produce coffee as an important cash crop. Yet coffee yields are poor. To increase farmers’ production, a range of agronomic practices have been recommended by national and international agencies. Yet the adoption potential of recommendations differs between farm systems. To understand the differences in adoption potential of recommended coffee management practices in Uganda, we provide a typology of farm systems with coffee, assess the diversity between the farm types, and evaluate the current use of existing management recommendations for each farm type. Through factor analysis and cluster analysis of farms producing coffee, we identified five farm types: large coffee farms, farms with off-farm activities, coffee-dependent farms, diversified farms, and banana–coffee farms. The farm types were based on differences in size, and on the relative contributions of coffee, banana and off-farm labour to total household income. They also differ in the availability of the resources labour, land and cash, in coffee production and revenue, and in current use of most recommended practices. Qualitative analysis indicates that farm types have different constraints and opportunities to adopt recommendations. Our results highlight that an analysis of different farm systems with coffee production, a degree of definition beyond the ‘smallholder coffee farmer’ as a homogenous entity, is important in order to understand the scope for success or failure of recommended practices.
Depressive symptoms are doubled in older British South Asian and Black Caribbean people compared with Europeans: associations with excess co-morbidity and socioeconomic disadvantage
Authors: Williams E. D. , Tillin T. , Richards M. , Tuson C. , Chaturvedi N. , Hughes A. D. , Stewart R. 
Published: February 2015

BackgroundDespite elevated risk profiles for depression among South Asian and Black Caribbean people in the UK, prevalences of late-life depressive symptoms across the UK's three major ethnic groups have not been well characterized.MethodData were collected at baseline and 20-year follow-up from 632 European, 476 South Asian and 181 Black Caribbean men and women (aged 58–88 years), of a community-based cohort study from north-west London. The 10-item Geriatric Depression Scale was interviewer-administered during a clinic visit (depressive symptoms defined as a score of ⩾4 out of 10), with clinical data (adiposity, diabetes, cardiovascular disease, cognitive function) also collected. Sociodemographic, psychosocial, behavioural, disability, and medical history information was obtained by questionnaire.ResultsPrevalence of depressive symptoms varied by ethnic group, affecting 9.7% of White European, 15.5% of South Asian, and 17.7% of Black Caribbean participants. Compared with White Europeans, South Asian and Black Caribbean participants were significantly more likely to have depressive symptoms (odds ratio 1.79, 95% confidence interval 1.24–2.58 and 1.80, 1.11–2.92, respectively). Adjustment for co-morbidities had most effect on the excess South Asian odds, and adjustment for socioeconomic position had most effect on the elevated Black Caribbean odds.ConclusionsHigher prevalence of depressive symptoms observed among South Asian people were attenuated after adjustment for physical health, whereas the Black Caribbean increased prevalence was most explained by socioeconomic disadvantage. It is important to understand the reasons for these ethnic differences to identify opportunities for interventions to address inequalities.
THE IMPACT OF IBN SĪNĀ'S CRITIQUE OF ATOMISM ON SUBSEQUENTKALĀMDISCUSSIONS OF ATOMISM
Authors: Dhanani Alnoor 
Published: February 2015

AbstractKalāmatomism stood in opposition to the Aristotelian natural philosophy of thefalāsifa. In thePhysicsof theShifā', Ibn Sīnā undertook a detailed refutation ofkalāmatomism through several arguments. These arguments elicited a muted response from al-Ghazālī, whose commitment tokalāmwas minimal at best. A more forceful response seems to have been offered by al-Shahrastānī but its details remain sketchy due to the lack of surviving sources. Fakhr al-Dīn al-Rāzī, whose intellectual development went through a phase of commitment to Avicennism and thereby a vigorous endorsement of Ibn Sīnā's anti-atomist arguments followed by a phase of a critical engagement with Avicennism, provides a detailed rebuttal to Ibn Sīnā's arguments in addition to constructing novel arguments in defense ofkalāmatomism.
LES DÉBUTS DE LA PROJECTION STÉRÉOGRAPHIQUE: CONCEPTION ET PRINCIPES
Authors: Abgrall Philippe 
Published: February 2015

AbstractIn thePlanisphaerium, Ptolemy deals with a method of representing a sphere onto a plane, according to principles which were compatible with the stereographic projection. But this projection will only become a real mathematical concept in the 9th century, when al-Farghānī will demonstrate the fundamental property of this projection. It is only in the 10th century that the first general theory of projections of spheres was worked out by al-Qūhī and Ibn Sahl. This paper addresses the reasons which allow to claim that Ptolemy did not conceive of projection and that this conception was based on the Apollonius' definition of the conical surface.
Wie spezifisch regulieren Studierende ihre Motivation bei unterschiedlichen Anlässen?
Authors: Engelschalk Tobias , Steuer Gabriele , Dresel Markus 
Published: February 2015

In der vorliegenden Arbeit wurde untersucht, wie Studierende abhängig von den spezifischen Ursachen mangelnder Lernmotivation (geringe Erfolgserwartung vs. geringer subjektiver Wert in drei Phasen der Lernhandlung) ihre Motivation regulieren. 54 Studierende gaben an, wie erfolgreich sie sich bei den genannten 2 × 3 Regulationsanlässen motivieren und welche Strategien sie jeweils einsetzen, um ihre Motivation zu verbessern. Die Ergebnisse zum Regulationserfolg verwiesen darauf, dass Studierenden die Regulation ihrer Motivation abhängig vom Anlass unterschiedlich gut gelingt. Die Analysen zur Strategiewahl zeigten, dass die Studierenden anlassspezifisch unterschiedliche Strategien wählen, über alle Studierenden hinweg aber nur ein geringer Konsens hinsichtlich der Passung von Strategien und Situationen besteht. Insgesamt wiesen die Ergebnisse darauf hin, dass Lernende verschiedene Ursachen mangelnder Motivation im Lernprozess wahrnehmen und spezifisch darauf reagieren.
Defining the phospho-adhesome through the phosphoproteomic analysis of integrin signalling
Authors: Robertson Joseph , Jacquemet Guillaume , Byron Adam , Jones Matthew C. , Warwood Stacey , Selley Julian N. , Knight David , Humphries Jonathan D. , Humphries Martin J. 
Published: February 2015

AbstractCell–extracellular matrix (ECM) adhesion is a fundamental requirement for multicellular existence due to roles in positioning, proliferation and differentiation. Phosphorylation plays a major role in adhesion signalling; however, a full understanding of the phosphorylation events that occur at sites of adhesion is lacking. Here we report a proteomic and phosphoproteomic analysis of adhesion complexes isolated from cells spread on fibronectin. We identify 1,174 proteins, 499 of which are phosphorylated (1,109 phosphorylation sites), including both well-characterized and novel adhesion-regulated phosphorylation events. Immunoblotting suggests that two classes of phosphorylated residues are found at adhesion sites—those induced by adhesion and those constitutively phosphorylated but recruited in response to adhesion. Kinase prediction analysis identifies novel kinases with putative roles in adhesion signalling including CDK1, inhibition of which reduces adhesion complex formation. This phospho-adhesome data set constitutes a valuable resource to improve our understanding of the signalling mechanisms through which cell–ECM interactions control cell behaviour.
Driving a GaAs film to a large-gap topological insulator by tensile strain
Authors: Zhao Mingwen , Chen Xin , Li Linyang , Zhang Xiaoming 
Published: February 2015

AbstractSearch for materials with a large nontrivial band gap is quite crucial for the realization of the devices using quantum spin Hall (QSH) effects. From first-principles calculations combined with a tight-binding (TB) model, we demonstrate that a trivial GaAs film with atomic thickness can be driven to a topological insulator with a sizable band gap by tensile strain. The strain-induced band inversion is responsible for the electronic structure transition. The nontrivial band gap due to spin-orbital coupling (SOC) is about 257 meV, sufficiently larger for the realization of QSH states at room temperature. This work suggests a possible route to the fabrication of QSH-based devices using the well-developed GaAs technology.
Study of DNA adsorption on mica surfaces using a surface force apparatus
Authors: Kan Yajing , Tan Qiyan , Wu Gensheng , Si Wei , Chen Yunfei 
Published: February 2015

AbstractWe report our studies on the adsorption properties of double-stranded DNA molecules on mica surfaces in a confined environment using a surface force apparatus. Specifically, we studied the influence of cation species and concentrations on DNA adsorption properties. Our results indicated that divalent cations (Mg2+ and Co2+) preferred to form uniform and moderately dense DNA layers on a mica substrate. By measuring the interactions between DNA-coated mica and bare mica in an aqueous solution, obvious adhesion was observed in a cobalt chloride solution, possibly due to the ion-correlation attraction between negatively charged DNA and the mica surface. Furthermore, the interaction differences that were observed with MgCl2 and CoCl2 solutions reveal that the specific adsorption behaviors of DNA molecules on a mica substrate were mediated by these two salts. Our results are helpful to elucidate the dynamics of DNA binding on a solid substrate.
Terahertz in-line digital holography of human hepatocellular carcinoma tissue
Authors: Rong Lu , Latychevskaia Tatiana , Chen Chunhai , Wang Dayong , Yu Zhengping , Zhou Xun , Li Zeyu , Huang Haochong , Wang Yunxin , Zhou Zhou 
Published: February 2015

AbstractTerahertz waves provide a better contrast in imaging soft biomedical tissues than X-rays and unlike X-rays, they cause no ionisation damage, making them a good option for biomedical imaging. Terahertz absorption imaging has conventionally been used for cancer diagnosis. However, the absorption properties of a cancerous sample are influenced by two opposing factors: an increase in absorption due to a higher degree of hydration and a decrease in absorption due to structural changes. It is therefore difficult to diagnose cancer from an absorption image. Phase imaging can thus be critical for diagnostics. We demonstrate imaging of the absorption and phase-shift distributions of 3.2 mm × 2.3 mm × 30-μm-thick human hepatocellular carcinoma tissue by continuous-wave terahertz digital in-line holography. The acquisition time of a few seconds for a single in-line hologram is much shorter than that of other terahertz diagnostic techniques and future detectors will allow acquisition of meaningful holograms without sample dehydration. The resolution of the reconstructions was enhanced by sub-pixel shifting and extrapolation. Another advantage of this technique is its relaxed minimal sample size limitation. The fibrosis indicated in the phase distribution demonstrates the potential of terahertz holographic imaging to obtain a more objective, early diagnosis of cancer.
Evidence of the hydrogen release mechanism in bulk MgH2
Authors: Nogita Kazuhiro , Tran Xuan Q. , Yamamoto Tomokazu , Tanaka Eishi , McDonald Stuart D. , Gourlay Christopher M. , Yasuda Kazuhiro , Matsumura Syo 
Published: February 2015

AbstractHydrogen has the potential to power much of the modern world with only water as a by-product, but storing hydrogen safely and efficiently in solid form such as magnesium hydride remains a major obstacle. A significant challenge has been the difficulty of proving the hydriding/dehydriding mechanisms and, therefore, the mechanisms have long been the subject of debate. Here we use in situ ultra-high voltage transmission electron microscopy (TEM) to directly verify the mechanisms of the hydride decomposition of bulk MgH2 in Mg-Ni alloys. We find that the hydrogen release mechanism from bulk (2 μm) MgH2 particles is based on the growth of multiple pre-existing Mg crystallites within the MgH2 matrix, present due to the difficulty of fully transforming all Mg during a hydrogenation cycle whereas, in thin samples analogous to nano-powders, dehydriding occurs by a ‘shrinking core’ mechanism.
Gate Tunable Relativistic Mass and Berry's phase in Topological Insulator Nanoribbon Field Effect Devices
Authors: Jauregui Luis A. , Pettes Michael T. , Rokhinson Leonid P. , Shi Li , Chen Yong P. 
Published: February 2015

AbstractTransport due to spin-helical massless Dirac fermion surface state is of paramount importance to realize various new physical phenomena in topological insulators, ranging from quantum anomalous Hall effect to Majorana fermions. However, one of the most important hallmarks of topological surface states, the Dirac linear band dispersion, has been difficult to reveal directly in transport measurements. Here we report experiments on Bi2Te3 nanoribbon ambipolar field effect devices on high-κ SrTiO3 substrates, where we achieve a gate-tuned bulk metal-insulator transition and the topological transport regime with substantial surface state conduction. In this regime, we report two unambiguous transport evidences for gate-tunable Dirac fermions through π Berry's phase in Shubnikov-de Haas oscillations and effective mass proportional to the Fermi momentum, indicating linear energy-momentum dispersion. We also measure a gate-tunable weak anti-localization (WAL) with 2 coherent conduction channels (indicating 2 decoupled surfaces) near the charge neutrality point and a transition to weak localization (indicating a collapse of the Berry's phase) when the Fermi energy approaches the bulk conduction band. The gate-tunable Dirac fermion topological surface states pave the way towards a variety of topological electronic devices.
Role of surface plasmon polaritons and other waves in the radiation of resonant optical dipole antennas
Authors: Jia Hongwei , Liu Haitao , Zhong Ying 
Published: February 2015

AbstractThe radiation of an electric dipole emitter can be drastically enhanced if the emitter is placed in the nano-gap of a metallic dipole antenna. By assuming that only surface plasmon polaritons (SPPs) are excited on the antenna, we build up an intuitive pure-SPP model that is able to comprehensively predict the electromagnetic features of the antenna radiation, such as the total or radiative emission rate and the far-field radiation pattern. With the model we can distinguish the respective contributions from SPPs and from other surface waves to the antenna radiation. It is found that for antennas with long arms that support higher-order resonances, SPPs provide a dominant contribution to the antenna radiation, while for other cases, the contribution of surface waves other than SPPs should be considered. The model reveals an intuitive picture that the enhancement of the antenna radiation is due to surface waves that are resonantly excited on the two antenna arms and that are further coupled into the nano-gap or scattered into free space. From the model we can derive a phase-matching condition that predicts the antenna resonance and the resultant enhanced radiation. The model is helpful for a physical understanding and intuitive design of antenna devices.
Facile synthesis of novel graphene sponge for high performance capacitive deionization
Authors: Xu Xingtao , Pan Likun , Liu Yong , Lu Ting , Sun Zhuo , Chua Daniel H. C. 
Published: February 2015

AbstractCapacitive deionization (CDI) is an effective desalination technique offering an appropriate route to obtain clean water. In order to obtain excellent CDI performance, a rationally designed structure of electrode materials has been an urgent need for CDI application. In this work, a novel graphene sponge (GS) was proposed as CDI electrode for the first time. The GS was fabricated via directly freeze-drying graphene oxide solution followed by annealing in nitrogen atmosphere. The morphology, structure and electrochemical performance of GS were characterized by scanning electron microscopy, Raman spectroscopy, nitrogen adsorption-desorption, X-ray photoelectron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The electrosorption performance of GS in NaCl solution was studied and compared with pristine graphene (PG). The results show that due to the unique 3D interconnected porous structure, large accessible surface area and low charge transfer resistance, GS electrode exhibits an ultrahigh electrosorption capacity of 14.9 mg g−1 when the initial NaCl concentration is ~500 mg L−1, which is about 3.2 times of that of PG (4.64 mg g−1) and to our knowledge, it should be the highest value reported for graphene electrodes in similar experimental conditions by now. These results indicate that GS should be a promising candidate for CDI electrode.