bluuebunny/crossref_metadata_2025_split huggingface dataset:
First principles view on chemical compound space: Gaining rigorous atomistic control of molecular properties
Authors: von Lilienfeld O. Anatole 
Published: February 2013

AbstractA well‐defined notion of chemical compound space (CCS) is essential for gaining rigorous control of properties through variation of elemental composition and atomic configurations. Here, we give an introduction to an atomistic first principles perspective on CCS. First, CCS is discussed in terms of variational nuclear charges in the context of conceptual density functional and molecular grand‐canonical ensemble theory. Thereafter, we revisit the notion of compound pairs, related to each other via “alchemical” interpolations involving fractional nuclear charges in the electronic Hamiltonian. We address Taylor expansions in CCS, property nonlinearity, improved predictions using reference compound pairs, and the ounce‐of‐gold prize challenge to linearize CCS. Finally, we turn to machine learning of analytical structure property relationships in CCS. These relationships correspond to inferred, rather than derived through variational principle, solutions of the electronic Schrödinger equation. © 2013 Wiley Periodicals, Inc.
Graphene‐Bonded and ‐Encapsulated Si Nanoparticles for Lithium Ion Battery Anodes
Authors: Wen Yang , Zhu Yujie , Langrock Alex , Manivannan Ayyakkannu , Ehrman Sheryl H. , Wang Chunsheng 
Published: February 2013

AbstractSilicon (Si) has been considered a very promising anode material for lithium ion batteries due to its high theoretical capacity. However, high‐capacity Si nanoparticles usually suffer from low electronic conductivity, large volume change, and severe aggregation problems during lithiation and delithiation. In this paper, a unique nanostructured anode with Si nanoparticles bonded and wrapped by graphene is synthesized by a one‐step aerosol spraying of surface‐modified Si nanoparticles and graphene oxide suspension. The functional groups on the surface of Si nanoparticles (50–100 nm) not only react with graphene oxide and bind Si nanoparticles to the graphene oxide shell, but also prevent Si nanoparticles from aggregation, thus contributing to a uniform Si suspension. A homogeneous graphene‐encapsulated Si nanoparticle morphology forms during the aerosol spraying process. The open‐ended graphene shell with defects allows fast electrochemical lithiation/delithiation, and the void space inside the graphene shell accompanied by its strong mechanical strength can effectively accommodate the volume expansion of Si upon lithiation. The graphene shell provides good electronic conductivity for Si nanoparticles and prevents them from aggregating during charge/discharge cycles. The functionalized Si encapsulated by graphene sample exhibits a capacity of 2250 mAh g−1 (based on the total mass of graphene and Si) at 0.1C and 1000 mAh g−1 at 10C, and retains 85% of its initial capacity even after 120 charge/discharge cycles. The exceptional performance of graphene‐encapsulated Si anodes combined with the scalable and one‐step aerosol synthesis technique makes this material very promising for lithium ion batteries.
Skills and abilities for working in a global software development team: a competence model
Authors: Saldaña‐Ramos Javier , Sanz‐Esteban Ana , García Javier , Amescua Antonio 
Published: February 2013

ABSTRACTNowadays, it is common to develop software development projects collaboratively among team members or organizations in different geographical locations. These teams, known as global software development (GSD) teams, allow organizations to save costs as well as have available highly qualified personnel. This kind of team is different from traditional teams, so it is necessary for team members to develop other essential competences to work efficiently in a global context. Unfortunately, there is no well‐defined competence model that allows organizations to assess personnel competences and establish the relevant training program that allows them to work efficiently in such teams. This work defines and implements, in four GSD teams, a competence model specifically designed to address challenges that people face when they work in a GSD team. This competence model has been defined considering tasks a GSD team have to carry out, bodies of knowledge, and existing competence models for the software engineering profiles and the authors' experience working in such teams. As a result of the implementation process, it was confirmed that the competence model is a key factor for human capital improvement. When personnel have these competences, team and individual efficiency and product quality increase, and delays in delivering products decrease. Copyright © 2013 John Wiley & Sons, Ltd.
Interpreting Student Views of Learning Experiences in a Contextualized Science Discourse in Kenya
Authors: Nashon Samson Madera , Anderson David 
Published: February 2013

AbstractDespite the centrality of the informal manufacturing sector (Jua Kali) to the Kenyan society and its richness in scientific phenomena, there is no strong link between activities in the Jua Kali and school science. And, although there has been an ongoing public discourse in Kenya to industrialize, this hope is unlikely without connecting classroom science to the real world of the Jua Kali. In view of this concern, an interpretive case study was framed to investigate Kenyan high school students' views of contextualized science learning in culturally relevant real‐world science curriculum. This article reports the analysis of Kenyan students' views of contextualized science learning and school science curriculum and instruction elicited through an interpretive case study approach employing interview methods. The analysis of interview data reveals that the participating students interviewed expressed views that: (1) acknowledged the richness of Jua Kali in scientific phenomena and embedded science; (2) indicated existence of a lack of meaningfulness and relevance in existing science curriculum and instruction model; (3) revealed experience of resonance of group and real life learning strategies modeled in the curriculum unit with their preferred learning modes; and (4) revealed their metacognitive assessment of the traditionally used and the new contextualized science modeled learning strategies. Thus, this article offers insight about the Kenyan students on their journey through the experience of contextualized science learning. © 2013 Wiley Periodicals, Inc. J Res Sci Teach 50: 381‐407, 2013
Detection and attribution of anthropogenic climate change impacts
Authors: Rosenzweig Cynthia , Neofotis Peter 
Published: February 2013

AbstractHuman‐influenced climate change is an observed phenomenon affecting physical and biological systems across the globe. The majority of observed impacts are related to temperature changes and are located in the northern high‐ and mid‐latitudes. However, new evidence is emerging that demonstrates that impacts are related to precipitation changes as well as temperature, and that climate change is impacting systems and sectors beyond the Northern Hemisphere. In this paper, we highlight some of this new evidence—focusing on regions and sectors that the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) noted as under‐represented—in the context of observed climate change impacts, direct and indirect drivers of change (including carbon dioxide itself), and methods of detection. We also present methods and studies attributing observed impacts to anthropogenic forcing. We argue that the expansion of methods of detection (in terms of a broader array of climate variables and data sources, inclusion of the major modes of climate variability, and incorporation of other drivers of change) is key to discerning the climate sensitivities of sectors and systems in regions where the impacts of climate change currently remain elusive. Attributing such changes to human forcing of the climate system, where possible, is important for development of effective mitigation and adaptation. Current challenges in documenting adaptation and the role of indigenous knowledge in detection and attribution are described. WIREs Clim Change 2013, 4:121–150. doi: 10.1002/wcc.209This article is categorized under:

Assessing Impacts of Climate Change > Observed Impacts of Climate Change
Holography for general gauge mediation
Authors: McGarrie Moritz 
Published: February 2013

AbstractWe construct a holographic model of spontaneous supersymmetry breaking in analogy to AdS/QCD models. Integrating out the bulk theory one obtains an entirely four dimensional effective action that encodes spontaneous supersymmetry breaking effects, coupled to external sources. Using only this four dimensional action it is possible to compute soft masses, scattering cross sections and determine the form factors of vector mesons. This construction lends itself to a more natural comparison with operator product expansions.
Long-lived higgsinos as probes of gravitino dark matter at the LHC
Authors: Bobrovskyi S. , Hajer J. , Rydbeck S. 
Published: February 2013

AbstractWe investigate the LHC sensitivity to supersymmetric models with light higgsinos, small R-parity breaking and gravitino dark matter. The limits on decaying gravitino dark matter from gamma-ray searches with the Fermi-LAT put a lower bound on the higgsino-like neutralino NLSP decay length, giving rise to a displaced-vertex collider signature. Using publicly available tools for simulation of signal, background and detector response, we find that higgsinos with masses of 100 – 400 GeV and R-parity violation ofζ~ 10−8– 10−9can show up in the 8 TeV LHC data with 10 – 30 fb−1of integrated luminosity. We demonstrate that in the case of a signal, the higgsino mass can be determined by reconstruction of the dimuon mass edge.
Inter‐annual variability of seed rain and seedling establishment of two woody Mediterranean species under field‐induced drought and warming
Authors: del Cacho Montse , Estiarte Marc , Peñuelas Josep , Lloret Francisco 
Published: February 2013

AbstractWe aimed to assess the impact of warmer and drier climate change conditions on the seed rain and seedling establishment of Globularia alypum L. and Erica multiflora L., two dominant species in Western coastal Mediterranean shrublands. We performed a non‐intrusive field experiment in which we increased the night‐time temperatures and excluded spring and autumn rainfall. We monitored the seed rain over 5 years and the seedling recruitment over 9 years on these experimental plots. Seed rain of E. multiflora was enhanced by warming treatment in relation to control, and higher annual rainfall, while seed rain of G. alypum was increased by drought treatment in relation to control, dry years and higher minimum annual temperature. Annual rainfall enhanced the seedling emergence of both species, which also positively correlated with annual mean temperatures. Drought treatment significantly decreased seedling emergence for both species, which was higher in open areas than below vegetation cover. The seedling survival of both species diminished at closer distances to competing neighbours, and in G. alypum seedling survival was higher with lower annual mean temperatures and higher annual rainfall, but also in drought treatment, which have experienced vegetation cover decline. The study confirms that the increasing aridity in Mediterranean ecosystems would constrain the early stages of development in typical co‐occurring shrubs. However, there are contrasting responses to climatic conditions between species recruitment, which might favour changes in vegetation through modification of species relative abundance.
Effects of increasing nutrient supply and omnivorous feeding on the size spectrum slope: a size‐based nutrient‐phytoplankton‐zooplankton model
Authors: Ho Pei‐Chi , Chang Chun‐Wei , Hsieh Chih Hao , Shiah Fuh‐Kwo , Miki Takeshi 
Published: February 2013

AbstractSize spectrum slope has been considered as an indicator for system productivity and size‐dependent trophic interactions in plankton communities. We investigated the effect of new nutrient flux (Nin) and feeding breadth of zooplankton (σ2) on spectral slopes of the plankton community using a size‐structured nutrient‐phytoplankton‐zooplankton model. We studied two types of plankton systems (1) at a steady state and (2) with fluctuating plankton populations. For the steady state systems, the spectral slopes increased with Nin and σ2. In contrast, for the systems in fluctuation, spectral slopes constructed from long‐term average plankton populations decreased with increasing Nin and σ2. In addition to spectral slopes constructed from long‐term average population densities, we investigated slope variability in systems with fluctuating plankton populations. The variability of spectral slopes was found to increase with Nin and σ2, indicating that spectral slope variation is large in a eutrophic system or when zooplankton feed on a wide size range of prey. Empirically, because Nin is difficult to measure, nutrient concentration is investigated instead. Our model predicts that the spectral slope is positively correlated with nutrient concentration due to the accumulated mesozooplankton biomass, which was confirmed by our study in plankton community in a subtropical reservoir in Taiwan.
Improving Classroom Quality with The RULER Approach to Social and Emotional Learning: Proximal and Distal Outcomes
Authors: Hagelskamp Carolin , Brackett Marc A. , Rivers Susan E. , Salovey Peter 
Published: February 2013

AbstractThe RULER Approach to Social and Emotional Learning (“RULER”) is designed to improve the quality of classroom interactions through professional development and classroom curricula that infuse emotional literacy instruction into teaching–learning interactions. Its theory of change specifies that RULER first shifts the emotional qualities of classrooms, which are then followed, over time, by improvements in classroom organization and instructional support. A 2‐year, cluster randomized controlled trial was conducted to test hypotheses derived from this theory. Sixty‐two urban schools either integrated RULER into fifth‐ and sixth‐grade English language arts (ELA) classrooms or served as comparison schools, using their standard ELA curriculum only. Results from multilevel modeling with baseline adjustments and structural equation modeling support RULER's theory of change. Compared to classrooms in comparison schools, classrooms in RULER schools exhibited greater emotional support, better classroom organization, and more instructional support at the end of the second year of program delivery. Improvements in classroom organization and instructional support at the end of Year 2 were partially explained by RULER's impacts on classroom emotional support at the end of Year 1. These findings highlight the important contribution of emotional literacy training and development in creating engaging, empowering, and productive learning environments.
Avoiding poor health or approaching good health: Does it matter? The conceptualization, measurement, and consequences of health regulatory focus
Authors: Gomez Pierrick , Borges Adilson , Pechmann Cornelia (Connie) 
Published: February 2013

AbstractThis research presents a new scale, the health regulatory focus scale, which measures an individual's tendency to use promotion or prevention strategies in the pursuit of health goals. We conducted five studies in France to develop the scale which is made up of two subscales for prevention and promotion. We also tested the scale's psychometric properties and demonstrated its two‐factor dimensionality, internal and test–retest reliability, and convergent, nomological, predictive and discriminant validity. The health subscales showed good predictive validity in that they correlated with health behaviors better than the general regulatory focus subscales. For instance, health promotion focus predicted dentist visits while general promotion focus did not, and health prevention focus predicted the use of prescription and over‐the‐counter drugs while general prevention focus did not. Also as expected, general prevention focus predicted avoidance of risky vacation behaviors while health prevention focus did not. The health subscales either did not correlate or correlated weakly with positive and negative affectivity and general risk aversion indicating good discriminant validity. The one‐year test–retest reliabilities were adequate for both subscales.
Estrogen receptor‐α36 is involved in development of acquired tamoxifen resistance via regulating the growth status switch in breast cancer cells
Authors: Li Guangliang , Zhang Jing , Jin Ketao , He Kuifeng , Zheng Yi , Xu Xin , Wang Haohao , Wang Haiyong , Li Zhongqi , Yu Xiongfei , Teng Xiaodong , Cao Jiang , Teng Lisong 
Published: February 2013

Acquired tamoxifen (TAM) resistance limits the therapeutic benefit of TAM in patients with hormone‐dependent breast cancer. The switch from estrogen‐dependent to growth factor‐dependent growth is a critical step in this process. However, the molecular mechanisms underlying this switch remain poorly understood. In this study, we established a TAM resistant cell sub line (MCF‐7/TAM) from estrogen receptor‐α (ER‐α66) positive breast cancer MCF‐7 cells by culturing ER‐α66‐positive MCF‐7 cells in medium plus 1 μM TAM over 6 months. MCF‐7/TAM cells were then found to exhibit accelerated proliferation rate together with enhanced in vitro migratory and invasive ability. And the estrogen receptor‐α36 (ER‐α36), a novel 36‐kDa variant of ER‐α66, was dramatically overexpressed in this in vitro model, compared to the parental MCF‐7 cells. Meanwhile, the expression of epidermal growth factor receptor (EGFR) in MCF‐7/TAM cells was significantly up‐regulated both in mRNA level and protein level, and the expression of ER‐α66 was greatly down‐regulated oppositely. In the subsequent studies, we overexpressed ER‐α36 in MCF‐7 cells by stable transfection and found that ER‐α36 transfected MCF‐7 cells (MCF‐7/ER‐α36) similarly exhibited decreased sensitivity to TAM, accelerated proliferative rate and enhanced in vitro migratory and invasive ability, compared to empty vector transfected MCF‐7 cells (MCF‐7/V). Real‐time qPCR and Western blotting analysis revealed that MCF‐7/ER‐α36 cells possessed increased EGFR expression but decreased ER‐α66 expression both in mRNA level and protein level, compared to MCF‐7/V cells. This change in MCF‐7/ER‐α36 cells could be reversed by neutralizing anti‐ER‐α36 antibody treatment. Furthermore, knock‐down of ER‐α36 expression in MCF‐7/TAM cells resulted in reduced proliferation rate together with decreased in vitro migratory and invasive ability. Decreased EGFR mRNA and protein expression as well as increased ER‐α66 mRNA expression were also observed in MCF‐7/TAM cells with down‐regulated ER‐α36 expression. In addition, blocking EGFR/ERK signaling in MCF‐7/ER‐α36 cells could restore the expression of ER‐α66 partly, suggesting a regulatory function of EGFR/ERK signaling in down‐regulation of ER‐α66 expression. In conclusion, our results indicated for the first time a regulatory role of ER‐α36 in up‐regulation of EGFR expression and down‐regulation of ER‐α66 expression, which could be an underlying mechanism for the growth status switch in breast tumors that contribute to the generation of acquired TAM resistance. And ER‐α36 could be considered a potential new therapeutic target in breast tumors which have acquired resistance to TAM.
Patient‐derived xenografts recapitulate molecular features of human uveal melanomas
Authors: Laurent Cécile , Gentien David , Piperno-Neumann Sophie , Némati Fariba , Nicolas André , Tesson Bruno , Desjardins Laurence , Mariani Pascale , Rapinat Audrey , Sastre-Garau Xavier , Couturier Jérôme , Hupé Philippe , de Koning Leanne , Dubois Thierry , Roman-Roman Sergio , Stern Marc-Henri , Barillot Emmanuel , Harbour J. William , Saule Simon , Decaudin Didier 
Published: February 2013

We have previously developed a new method for the development and maintenance of uveal melanoma (UM) xenografts in immunodeficient mice. Here, we compare the genetic profiles of the primary tumors to their corresponding xenografts that have been passaged over time. The study included sixteen primary UMs and corresponding xenografts at very early (P1), early (P4), and late (P9) in vivo passages. The tumors were analyzed for mutation status of GNAQ, GNA11, GNAS, GNA15, BAP1, and BRAF, chromosomal copy number alterations using Affymetrix GeneChip® Genome‐Wide Human SNP6.0 arrays, gene expression profiles using GeneChip® Human Exon 1.0 ST arrays, BAP1 mRNA and protein expression, and MAPK pathway status using Reverse Phase Protein Arrays (RPPA). The UM xenografts accurately recapitulated the genetic features of primary human UMs and they exhibited genetic stability over the course of their in vivo maintenance. Our technique for establishing and maintaining primary UMs as xenograft tumors in immunodeficient mice exhibit a high degree of genetic conservation between the primary tumors and the xenograft tumors over multiple passages in vivo. These models therefore constitute valuable preclinical tool for drug screening in UM.
CREATING SYNERGIES BETWEEN CONSERVATION AGRICULTURE AND CATTLE PRODUCTION IN CROP–LIVESTOCK FARMS: A STUDY CASE IN THE LAKE ALAOTRA REGION OF MADAGASCAR
Authors: ANDRIARIMALALA J. H. , RAKOTOZANDRINY J. N. , ANDRIAMANDROSO A. L. H. , PENOT E. , NAUDIN K. , DUGUÉ P. , TILLARD E. , DECRUYENAERE V. , SALGADO P. 
Published: February 2013

SUMMARYConservation agriculture (CA) has been promoted as a strategy to cope with deterioration in soil fertility, but its adoption on smallholder farms in tropical areas remains limited. In Madagascar, livestock production is facing shortages in forage especially during the dry season. The value of cover crops used in CA as livestock feed could be an incentive to make this form of agriculture more acceptable in rural areas. To do so, farmers must find a trade-off between the use of biomass from cover crops for animal production and its maintenance on the soil to meet CA's criteria. In this study, we evaluated the impact of biomass flows (cover crops and manure) between cropping and cattle production in crop–livestock farms in the Lake Alaotra region. Surveys among crop–livestock farmers were used to calculate feed concentrate and mineral fertilizer equivalents. Our results show that on average 42, 22 and 10% of biomass production (dry matter basis) of Brachiaria spp., Stylosanthes guianensis and Vicia villosa, respectively, are used for livestock feeding. The economic benefit in feed concentrate equivalent is between €73 and €723/year per farm. The use of manure contributes, just as CA, to improve soil fertility without using external fertilizing resources. The economic benefit in mineral fertilizer equivalent is between €116 and €2365/year per farm. The integration of CA and livestock production shows, beyond the agronomic advantages, an obvious economic benefit, which is essential to secure the Malagasy agricultural systems. Moreover, this economic benefit is another argument for the dissemination of CA practices in rural areas.