Suckers (Fish, Catostomidae) from the Eocene of China account for the family's current disjunct distributions

Unequivocal Eocene suckers from China are for the first time reported here. This discovery demonstrates that catostomids of the Eocene Epoch (some 55-35 Ma ago) are scattered widely on mainland Asia as well as western North America. The present day disjunct distribution pattern of catostomids, with 68 extant species widespread in North America and the northern part of Middle America and only two in the restricted areas of Asia, is the result of their post-Eocene decline in Asia due to the competitive pressure from cyprinids, their Late Cenozoic radiation in North America, and the vicariant and dispersal events triggered by the changed biogeographic landscape. All of these prove to be a historical product of the geological, biological, and climatic changes throughout the Cenozoic.

辽河流域降雨侵蚀力的时空变化分析

降雨侵蚀力是反映流域降雨侵蚀能力的综合指标之一。根据辽河流域10个气象站的日降雨量资料,利用日降雨侵蚀力模型估算辽河流域的降雨侵蚀力。结果表明:辽河流域降雨侵蚀力的空间变异与降雨量的空间分布趋势基本一致,由东南向西北递减,变化于1 000~3 800 MJ.mm/(hm2.h.a)之间;降雨侵蚀力年内集中度高,6—8月3个月约占全年的80%;降雨侵蚀力年际变化大,年际变率Cv在0.367~0.649之间,采用时序系列的Mann-Kendall检验表明,降雨侵蚀力并无显著变化趋势;特别是在流域水土流失严重的西辽河地区,年降雨侵蚀力较小,但年内集中程度大,年际变化更突出。

Di-nuclear systems studied with the velocity filter SHIP

Various nuclear reactions like quasi-fission, fusion-fission or particle and cluster evaporation from excited compound nuclei were studied in heavy-ion reactions at the velocity filter SHIP of GSI. The velocity filter offers the possibility to detect all reaction products under zero degree relative to the beam direction. Together with the measurement of the product velocity distribution this allows for an identification of the underlying reaction mechanism. This article is focussed on reactions of Mg-25 and Ni-64 beams on Pb-206,Pb-207 targets at energies of 5.9 x A MeV and 8.7 x A MeV. Besides evaporation residues from Mg-25 + Pb-206 collisions we found evidence for rotation and quasi-fission of nuclear molecules formed in the entrance channel after the capture stage. The break-up of the systems showed a preferred clustering leading to isotopes in the region 84 <= Z <= 88 and 122 <= N <= 127 of the chart of nuclei.

长白山地区近50年平均最高和最低气温变化

利用线性趋势法对长白山地区13个气象台站建站以来的逐日温度资料进行分析,确定该区域的气温变化趋势,同时通过Mann-Kendall方法确定突变点位置,并结合t检验法进行检验。结果表明:区域的年平均最高气温和最低气温都有极为显著的增加趋势,分别为每10年增加了0.23和0.46℃(α=0.001);近50年的最高气温和最低气温的时间系列都有一个突变点,其中最高气温的突变点出现在1995年左右,最低气温的突变点在1985年前后。这种变化使得温度日较差表现出明显的减小趋势,并在1972年出现一个突变点,前后平均相差0.8℃。区域各月最高、最低气温及气温日较差与日照百分率均有极为显著的相关关系,一定程度上反映了温室效应持续增强的迹象。

Double twist in helical polymer "soft" crystals

In natural and synthetic materials having non-racemic chiral centers, chirality and structural ordering each play a distinct role in the formation of ordered states. Configurational chirality can be extended to morphological chirality when the phase, structures possess low liquid crystalline order. In the crystalline states the crystallization process suppresses the chiral helical morphology due to strong ordering interactions, In this Letter, we report the first observation of helical single lamellar crystals of synthetic non-racemic chiral polymers. Experimental evidence shows that the molecular chains twist along both the long and short axes of the helical lamellar crystals, which is the first time a double-twist molecular orientation in a helical crystal has been observed.

Sobrecargas posturais

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária

An exploratory study on the impact of an early years' preschool intervention programme in the Republic of Ireland

Early years’ education has increasingly been identified as a mechanism to alleviate educational disadvantage in areas of social exclusion. Early years’ intervention programmes are now a common government social policy for addressing social problems (Reynolds, Mann, Miedel, and Smokowski, 1997). In particular, state provided early years’ programmes such as Head Start in the United States and Early Start in Ireland have been established to combat educational disadvantage for children experiencing poverty and socio-economic inequality. The focus of this research is on the long-term outcomes of an early years’ intervention programme in Ireland. It aims to assess whether participation in the programme enhances the life course of children at-risk of educational disadvantage. It involves an in-depth analysis of one Early Start project which was included in the original eight projects established by the Department of Education and Science in 1994. The study utilises a multi-group design to provide a detailed analysis of both the academic and social progress of programme participants. It examines programme outcomes from a number of perspectives by collecting the views of the three main stakeholders involved in the education process; students who participated in Early Start in 1994/5, their parents and their teachers. To contribute to understanding the impact of the programme from a community perspective interviews were also conducted with local community educators and other local early years’ services. In general, Early Start was perceived by all participants in this study as making a positive contribution to parent involvement in education and to strengthening educational capital in the local area. The study found that parents and primary school teachers identified aspects of school readiness as the main benefit of participation in Early Start and parents and teachers were very positive about the role of Early Start in preparing children for the transition to formal school. In addition to this, participation in Early Start appears to have made a positive contribution to academic attainment in Maths and Science at Junior Certificate level. Students who had participated in Early Start were also rated more highly by their second level teachers in terms of goal-setting and future orientation which are important factors in educational attainment. Early Start then can be viewed as providing a positive contribution to the long-term social and academic outcomes for its participants.

Nonlinear piezoelectricity in electroelastic energy harvesters: Modeling and experimental identification

We propose and experimentally validate a first-principles based model for the nonlinear piezoelectric response of an electroelastic energy harvester. The analysis herein highlights the importance of modeling inherent piezoelectric nonlinearities that are not limited to higher order elastic effects but also include nonlinear coupling to a power harvesting circuit. Furthermore, a nonlinear damping mechanism is shown to accurately restrict the amplitude and bandwidth of the frequency response. The linear piezoelectric modeling framework widely accepted for theoretical investigations is demonstrated to be a weak presumption for near-resonant excitation amplitudes as low as 0.5 g in a prefabricated bimorph whose oscillation amplitudes remain geometrically linear for the full range of experimental tests performed (never exceeding 0.25% of the cantilever overhang length). Nonlinear coefficients are identified via a nonlinear least-squares optimization algorithm that utilizes an approximate analytic solution obtained by the method of harmonic balance. For lead zirconate titanate (PZT-5H), we obtained a fourth order elastic tensor component of c1111p =-3.6673× 1017 N/m2 and a fourth order electroelastic tensor value of e3111 =1.7212× 108 m/V. © 2010 American Institute of Physics.

The potential of natural, photosynthetic pigments to improve the efficiency of dye-sensitized solar cells

Gemstone Team Grenergy

Application of the Intervention Mapping protocol to develop Keys, a family child care home intervention to prevent early childhood obesity.

BACKGROUND: Many families rely on child care outside the home, making these settings important influences on child development. Nearly 1.5 million children in the U.S. spend time in family child care homes (FCCHs), where providers care for children in their own residences. There is some evidence that children in FCCHs are heavier than those cared for in centers. However, few interventions have targeted FCCHs for obesity prevention. This paper will describe the application of the Intervention Mapping (IM) framework to the development of a childhood obesity prevention intervention for FCCHs METHODS: Following the IM protocol, six steps were completed in the planning and development of an intervention targeting FCCHs: needs assessment, formulation of change objectives matrices, selection of theory-based methods and strategies, creation of intervention components and materials, adoption and implementation planning, and evaluation planning RESULTS: Application of the IM process resulted in the creation of the Keys to Healthy Family Child Care Homes program (Keys), which includes three modules: Healthy You, Healthy Home, and Healthy Business. Delivery of each module includes a workshop, educational binder and tool-kit resources, and four coaching contacts. Social Cognitive Theory and Self-Determination Theory helped guide development of change objective matrices, selection of behavior change strategies, and identification of outcome measures. The Keys program is currently being evaluated through a cluster-randomized controlled trial CONCLUSIONS: The IM process, while time-consuming, enabled rigorous and systematic development of intervention components that are directly tied to behavior change theory and may increase the potential for behavior change within the FCCHs.

Evaluating Alternative Nutrient Sources in Subsistence-Level Aquaponic Systems

Many food production methods are both economically and environmentally unsustainable. Our project investigated aquaponics, an alternative method of agriculture that could address these issues. Aquaponics combines fish and plant crop production in a symbiotic, closed-loop system. We aimed to reduce the initial and operating costs of current aquaponic systems by utilizing alternative feeds. These improvements may allow for sustainable implementation of the system in rural or developing regions. We conducted a multi-phase process to determine the most affordable and effective feed alternatives for use in an aquaponic system. At the end of two preliminary phases, soybean meal was identified as the most effective potential feed supplement. In our final phase, we constructed and tested six full-scale aquaponic systems of our own design. Data showed that soybean meal can be used to reduce operating costs and reliance on fishmeal. However, a more targeted investigation is needed to identify the optimal formulation of alternative feed blends.

Sistemas de evaluación de tierras y elaboración de modelos de aptitud de uso agrícola, para distintos escenarios climáticos, en un sector de la subregión pampa arenosa (Provincia de Buenos Aires, Argentina)

La Pampa Arenosa ha sido escenario de cambios en el uso del territorio que respondieron principalmente al aumento de las precipitaciones a partir de la década del 70. La evaluación de las tierras es una etapa crítica en la planificación del uso sustentable. Por este motivo, se analizaron distintos sistemas de evaluación de tierras y se desarrollaron modelos expertos que consideren los factores ambientales heredados y las variaciones climáticas, para el sector de dunas longitudinales de la Pampa Arenosa en la Provincia de Buenos Aires, a escala 1: 50.000, considerando a los partidos de Nueve de Julio, Carlos Casares, Pehuajó y Trenque Lauquen. Las tierras fueron clasificadas por Capacidad de Uso, Indice de Productividad (IP) y se generaron sistemas expertos, utilizando el programa ALES, para los tipos de utilización de las tierras (TUTs) : maíz, soja y trigo. La homogeneidad de las series climáticas de precipitaciones se determinó mediante el test de Rachas. La aplicación del test de Pettitt permitió identificar la existencia de un cambio abrupto en las precipitaciones y el este de Mann Kendall mostró una tendencia creciente en relación a la precipitación anual. Las tierras con severas (clase III) y muy severas limitaciones (clase IV), fueron las más frecuentes ocupando el 42,6 por ciento y 29,8 por ciento respectivamente del área. Se comprobó que el IP de las tierras se incrementó con el aumento de las precipitaciones, alcanzando su máxima expresión climática en el período posterior al cambio abrupto. Las tierras de moderada capacidad productiva con valores de IP entre 65-51 ocuparon la mayor superficie de área de estudio. Los modelos expertos según los TUTs presentaron una aptitud de uso de las tierras variable, condicionada por la capacidad de retención hídrica de los suelos. Los modelos expertos fueron sensibles a las variaciones climáticas y el cambio abrupto en las precipitaciones.