A low-loss photonic silica nanofiber for higher-order modes

Optical nanofibers confine light to subwavelength scales, and are of interest for the design, integration, and interconnection of nanophotonic devices. Here we demonstrate high transmission (> 97%) of the first family of excited modes through a 350 nm radius fiber, by appropriate choice of the fiber and precise control of the taper geometry. We can design the nanofibers so that these modes propagate with most of their energy outside the waist region. We also present an optical setup for selectively launching these modes with less than 1% fundamental mode contamination. Our experimental results are in good agreement with simulations of the propagation. Multimode optical nanofibers expand the photonic toolbox, and may aid in the realization of a fully integrated nanoscale device for communication science, laser science or other sensing applications.Comment: 12 pages, 5 figures, movies available onlin

The Complementary Brain: From Brain Dynamics To Conscious Experiences

How do our brains so effectively achieve adaptive behavior in a changing world? Evidence is reviewed that brains are organized into parallel processing streams with complementary properties. Hierarchical interactions within each stream and parallel interactions between streams create coherent behavioral representations that overcome the complementary deficiencies of each stream and support unitary conscious experiences. This perspective suggests how brain design reflects the organization of the physical world with which brains interact, and suggests an alternative to the computer metaphor suggesting that brains are organized into independent modules. Examples from perception, learning, cognition, and action are described, and theoretical concepts and mechanisms by which complementarity is accomplished are summarized.Defense Advanced Research Projects and the Office of Naval Research (N00014-95-1-0409); National Science Foundation (ITI-97-20333); Office of Naval Research (N00014-95-1-0657

Pengembangan Multimedia IPA Berbasis Flash untuk Meningkatkan Literasi Sains Siswa SMP

This research aims to develop Flash-based IPA multimedia that is valid, practical, and effective to train students' scientific literacy on the subject of Excretion Systems in humans. The target of the study was multimedia science that was tested on 35 grade VIII junior high school students with the design of One-Group Pretest-Posttest Design. Quantitative-qualitative data analysis with results: (a) valid multimedia validation (3.5); (b) the implementation of learning is very good (3.7); (c) student activities reach 97.9%; positive student response (97%); (d) students' scientific literacy abilities increase from level 1b (students demonstrate little facts in content, procedural and epistemic knowledge, evaluate and design questions and interpret data in a few situations) to level 3 (students can use content, procedural, and epistemic knowledge to explain, evaluate and design scientific questions and interpret data in several life situations) to level 6 (students can use content, procedural knowledge, and design questions and interpret data in complex situations to reach the highest level in the cognitive domain). The conclusion of this study, that Flash-based science multimedia is feasible to train science literacy of junior high school students

The Development of Physics Students’ Worksheets Based on Science Process Skills in Basic Physics Course At Flores University

This study aims to determine the feasibility level of physics worksheets and to figure out the increase on student’s understanding after using the physics worksheets based on science process skills. This study is a development research employing ADDIE development model which consists of five stages, namely: analysis, design, development, and implementation. The design of this study was One Group Pretest-Posttest Design. The instruments used were validity assessment sheet, feasibility assessment sheet, questionnaire about the students’ response toward the worksheets based on science process skills, and assessment of science process skills. the data were analyzed by using percentage of agreement (R), and N-gain (g). The results showed that the physics students’ worksheet based on science process skills was feasible and could be used in learning as the feasibility level reached 97%. The students’ understanding of fluid material gained through working with the worksheets can improve students’ science process skills both at the basic level and at the integrated level. This is proven by the results of the initial test or pre-test which indicate that the students' science process skills affected the learning outcomes obtained in which 62.25% of students’ scores were in good category and 35.75% of students’ scores were in fair category. Meanwhile, in the final test or post-test of students' science process skills, it was obtained that 74.50% of students’ scores were in very good category and 25.50% of students’ scores were in the fair category. This means that there is an increase by 0.7 % in students' science process skills when using the students’ worksheets

Teachers’ Attitude and Gender Factor as Determinant of Pupils’ performance in Primary Science

Teachers are regarded as the basic tools in education and curriculumimplementations. The quality of any nation’s education is determined by the qualities of the teachers and their attitude to the profession. This paper seeks to examine the influence of the teachers’ attitude and gender factor on the academic performance of the primary schools pupils. Fifty science teachers were randomly selected from seventy (70) primary schools out of the ninetyseven (97) primary schools in ondo west local Government in ondo state and two hundred pupils were randomly selected and used for the same study. Two instruments were used to collect data, the Teachers’ attitude questionnaire (TAQ) and Primary science achievement test (PSAT) .The research design adopted for this study was survey design. The reliability of the instrument was 0.78 and 0.84 by using crombach alpha and k-21 respectively. Pearson moment product correlation coefficient was used to analyze the instruments. The result indicated that there exists a significant relationship between teachers’ attitude and pupils’ performance in primary science. The result also indicated that there exists no significant relationship between the performance of pupils taught by male and female teachers inprimary science. Recommendations were made on how to promote furtherdevelopment of primary science teaching and learning in Nigeria.Key words: Attitude, Gender, Performance, Nigeri

Organic dairy farms in the EU: Productions systems, economics and future development

Organic farming is increasingly considered in the European Common Agricultural Policy. Sound evaluations of the effects of policy measures on organic farms in the EU are needed to face the challenges in future policy design. The effects of various policy scenarios on profitability and development strategies of typical organic dairy farms are analysed for the EU countries––Germany, Denmark, the United Kingdom and Italy. Based on an approach which links simulation modelling and focus groups consisting of farmers and advisors, profitability of typical farms is analysed, the impact of policy scenarios (Agenda 2000 and two alternatives) simulated and farm adaptation strategies forecasted. Size, structure, productivity, profitability and policy environment surrounding typical organic farms differ widely between countries. Dairy farms will benefit from Agenda 2000. In adaptation to Agenda 2000 they are expected to either grow or diversify production. Two extreme alternative scenarios are also analysed in their impacts on organic farms, a supply-policy driven scenario (I) and a demand-induced scenario (II). Scenario I results in higher profitability of organic farms than scenario II in the long term, while Scenario II results are similar to Agenda 2000 effects in the long term. Adaptation strategies to alternative scenarios are similar to the ones forecasted for Agenda 2000. from: Häring, A. M. (2003):Organic dairy farms in the EU: Productions systems, economics and future development. Livestock Production Science 80(1-2):89-97

Ambivalence in digital health: co-designing an mHealth platform for HIV care

In reaction to polarised views on the benefits or drawbacks of digital health, the notion of ‘ambivalence’ has recently been proposed as a means to grasp the nuances and complexities at play when digital technologies are embedded within practices of care. This article responds to this proposal by demonstrating how ambivalence can work as a reflexive approach to evaluate the potential implications of digital health. We first outline current theoretical advances in sociology and organisation science and define ambivalence as a relational and multidimensional concept that can increase reflexivity within innovation processes. We then introduce our empirical case and highlight how we engaged with the HIV community to facilitate a co-design space where 97 patients (across five European clinical sites: Antwerp, Barcelona, Brighton, Lisbon, Zagreb) were encouraged to lay out their approaches, imaginations and anticipations towards a prospective mHealth platform for HIV care. Our analysis shows how patients navigated ambivalence within three dimensions of digital health: quantification, connectivity and instantaneity. We provide examples of how potential tensions arising through remote access to quantified data, new connections with care providers or instant health alerts were distinctly approached alongside embodied conditions (e.g. undetectable viral load) and embedded socio-material environments (such as stigma or unemployment). We conclude that ambivalence can counterbalance fatalistic and optimistic accounts of technology and can support social scientists in taking-up their critical role within the configuration of digital health interventions

The Role of Language in Anatomy and Physiology Instruction

Research indicates that student learning of science, student attitudes toward science, and their motivation to learn science and pursue science-related careers is related to classroom instruction. This study examined anatomy and physiology (A&P) classes in a south Texas high school where 97 percent of students are Hispanic bilingual learners. Classes were assigned to control or treatment groups, with the treatment group receiving instruction designed to help students develop a deeper understanding of anatomy vocabulary related to brain structures by making connections to these words in everyday life as well as to their understanding of Spanish. Main effects between group and test scores were significant, with the control group reporting higher test scores than the treatment group. We attribute this finding to a bleed-over of the treatment group instructional design to the control group. In addition, significant differences in mean and median scores were observed with respect to intrinsic motivation and self-efficacy. The statistically significant increases in learning for both groups suggests the activity-, problem-, and project-based (APB) curriculum has the potential to be an effective type of instruction, especially for bilingual learners

Abdominal Aortic Aneurysm Genetic Associations: Mostly False? A Systematic Review and Meta-analysis

Objective/BackgroundMany associations between abdominal aortic aneurysm (AAA) and genetic polymorphisms have been reported. It is unclear which are genuine and which may be caused by type 1 errors, biases, and flexible study design. The objectives of the study were to identify associations supported by current evidence and to investigate the effect of study design on reporting associations.MethodsData sources were MEDLINE, Embase, and Web of Science. Reports were dual-reviewed for relevance and inclusion against predefined criteria (studies of genetic polymorphisms and AAA risk). Study characteristics and data were extracted using an agreed tool and reports assessed for quality. Heterogeneity was assessed using I2 and fixed- and random-effects meta-analyses were conducted for variants that were reported at least twice, if any had reported an association. Strength of evidence was assessed using a standard guideline.ResultsSearches identified 467 unique articles, of which 97 were included. Of 97 studies, 63 reported at least one association. Of 92 studies that conducted multiple tests, only 27% corrected their analyses. In total, 263 genes were investigated, and associations were reported in polymorphisms in 87 genes. Associations in CDKN2BAS, SORT1, LRP1, IL6R, MMP3, AGTR1, ACE, and APOA1 were supported by meta-analyses.ConclusionUncorrected multiple testing and flexible study design (particularly testing many inheritance models and subgroups, and failure to check for Hardy–Weinberg equilibrium) contributed to apparently false associations being reported. Heterogeneity, possibly due to the case mix, geographical, temporal, and environmental variation between different studies, was evident. Polymorphisms in nine genes had strong or moderate support on the basis of the literature at this time. Suggestions are made for improving AAA genetics study design and conduct

Effects of Highlights on Gloss Perception

The perception of a glossy surface in a static monochromatic image can occur when a bright highlight is embedded in a compatible context of shading and a bounding contour. Some images naturally give rise to the impression that a surface has a uniform reflectance, characteristic of a shiny object, even though the highlight may only cover a small portion of the surface. Nonetheless, an observer may adopt an attitude of scrutiny in viewing a glossy surface, whereby the impression of gloss is partial and nonuniform at image regions outside of a higlight. Using a rating scale and small probe points to indicate image locations, differential perception of gloss within a single object is investigate in the present study. Observers' gloss ratings are not uniform across the surface, but decrease as a function of distance from highlight. When, by design, the distance from a highlight is uncoupled from the luminance value at corresponding probe points, the decrease in rated gloss correlates more with the distance than with the luminance change. Experiments also indicate that gloss ratings change as a function of estimated surface distance, rather than as a function of image distance. Surface continuity affects gloss ratings, suggesting that apprehension of 3D surface structure is crucial for gloss perception.Air Force Office of Scientific Research (F49620-98-1-0108), Defense Advanced Research Projects Agency and the Office of Naval Research (N00014-95-1-0409), National Science Foundation (IIS-97-20333); Office of Naval Research (N00014-95-1-0657, N00014-01-1-0624); Whitaker Foundation (RG-99-0186