Oceanography Professional Development in Virginia Via Collaboration, Field Integration, and Inquiry

Seventy-nine in-service teachers completed one of six sections of a grant-funded, graduate-level, summer course entitled, Oceanography, that was offered at four different locations in Virginia between 2005 and 2007. The majority of the teachers enrolled with the objective of obtaining their add-on earth science endorsement through the Virginia Earth Science Collaborative (VESC). Oceanography was designed to integrate the following: 1) the ocean science disciplines of geology, chemistry, physics, and biology; 2) inquiry-based learning strategies, quantitative activities, and technology; and, 3) Virginia Institute of Marine Science (VIMS) field experience with classroom experiences. These design themes were informed by ocean science content standards and science education best practices, and supported the goal that, upon completion of the course, teachers would be confident and competent in their abilities to teach oceanography concepts to grades 6-12 [1-3]. Learning outcomes, instructor feedback, and participant feedback suggest that the VESC’s Oceanography can serve as an instructional model for teacher professional development in oceanography. A collaborative instructional framework (marine educators, master teacher, and university faculty), small class size, and end-of-course field synthesis projects are additional elements that contributed to positive learning outcomes in course sections. The primary challenge in the course was the compressed, two-week time frame of face-to-face instruction

Parton Energy Loss in Two-Stream Plasma System

The energy loss of a fast parton scattering elastically in a weakly coupled quark-gluon plasma is formulated as an initial value problem. The approach is designed to study an unstable plasma, but it also reproduces the well known result of energy loss in an equilibrium plasma. A two-stream system, which is unstable due to longitudinal chromoelectric modes, is discussed here some detail. In particular, a strong time and directional dependence of the energy loss is demonstrated.Comment: 6 pages; presented by K. Deja at the conference Strangeness in Quark Matter, Cracow, Poland, September 18-24, 201

Density Fluctuations in the Quark-Gluon Plasma

Using the kinetic theory we discuss how the particle and energy densities of the quark-gluon plasma fluctuate in a space-time cell. The fluctuations in the equilibrium plasma and in that one from the early stage of ultrarelativistic heavy-ion collisions are estimated. Within the physically interesting values of the parameters involved the fluctuations appear sizeable in both cases.Comment: 8 pages, no macro

Dominance of backward stimulated Raman scattering in gas-filled hollow-core photonic crystal fibers

Backward stimulated Raman scattering in gases provides a promising route to compression and amplification of a Stokes seed-pulse by counter-propagating against a pump-pulse, as has been already demonstrated in various platforms, mainly in free-space. However, the dynamics governing this process when seeded by noise has not yet been investigated in a fully controllable collinear environment. Here we report the first unambiguous observation of efficient noise-seeded backward stimulated Raman scattering in a hydrogen-filled hollow-core photonic crystal fiber. At high gas pressures, when the backward Raman gain is comparable with, but lower than, the forward gain, we report quantum conversion efficiencies exceeding 40% to the backward Stokes at 683 nm from a narrowband 532-nm-pump. The efficiency increases to 65% when the backward process is seeded by a small amount of back-reflected forward-generated Stokes light. At high pump powers the backward Stokes signal, emitted in a clean fundamental mode and spectrally pure, is unexpectedly always stronger than its forward-propagating counterpart. We attribute this striking observation to the unique temporal dynamics of the interacting fields, which cause the Raman coherence (which takes the form of a moving fine-period Bragg grating) to grow in strength towards the input end of the fiber. A good understanding of this process, together with the rapid development of novel anti-resonant-guiding hollow-core fibers, may lead to improved designs of efficient gas-based Raman lasers and amplifiers operating at wavelengths from the ultraviolet to the mid-infrared.Comment: 6 pages and 8 figures in the main section. 4 pages and 5 figures in the supplementary sectio

Shaping educational attitudes and aspirations: the influence of parents, place and poverty: stage 1 report

An interim report of a study which aims to better understand the relationship between children’s aspirations in relation to education and employment, and the context in which they are formed. In particular, the study seeks to explore how parental circumstances and attitudes, the school as an institution, and the opportunity structures of the neighbourhood come together to shape aspirations in deprived urban areas. This report examines: • The assumptions of current policy that aspirations are a key ingredient of educational and labour market outcomes; • What aspirations are and how they can be understood; • What young people’s aspirations are for further and higher education and for future occupations in three secondary schools; • The main influences on those aspirations, including the roles of parents, schools and the neighbourhood context • Messages for the second stage of the research and emerging lessons for policy. The report provides some evidence to question the assumption among policy makers that there is a ‘poverty of aspirations’ among young people from disadvantaged backgrounds or living in disadvantaged neighbourhoods

Quasiquarks in two stream system

We study the collective quark excitations in an extremely anisotropic system of two interpenetrating streams of the quark-gluon plasma. In contrast to the gluon modes, all quark ones appear to be stable in such a system. Even more, the quark modes in the two-stream system are very similar to those in the isotropic plasma.Comment: 4 pages, 2 figures, minor corrections, to appear in Phys. Rev.

Chromodynamic Weibel instabilities in relativistic nuclear collisions

Employing a previously derived formulation, and extending the treatment from purely transverse modes to wave vectors having a longitudinal component, we discuss the prospects for the occurrence of Weibel-type color-current filamentation in high-energy nuclear collisions. Numerical solutions of the dispersion equation for a number of scenarios relevant to RHIC and LHC suggest that modes with (predominantly transverse) wave numbers of several hundred MeV may become moderately agitated during the early collision stage. The emergence of filamentation helps to speed up the equilibration of the parton plasma and it may lead to non-statistical azimuthal patterns in the hadron final state.Comment: 11 pages, RevTex, 13 (e)ps files (revised for PRC

Video Evidence That London Infants Can Resettle Themselves Back to Sleep After Waking in the Night, as well as Sleep for Long Periods, by 3 Months of Age

Objective: Most infants become settled at night by 3 months of age, whereas infants not settled by 5 months are likely to have long-term sleep-waking problems. We assessed whether normal infant development in the first 3 months involves increasing sleep-period length or the ability to resettle autonomously after waking in the night. Methods: One hundred one infants were assessed at 5 weeks and 3 months of age using nighttime infrared video recordings and parental questionnaires. Results: The clearest development was in sleep length; 45% of infants slept continuously for 5 hours or more at night at 3 months compared with 10% at 5 weeks. In addition, around a quarter of infants woke and resettled themselves back to sleep in the night at each age. Autonomous resettling at 5 weeks predicted prolonged sleeping at 3 months suggesting it may be a developmental precursor. Infants reported by parents to sleep for a period of 5 hours or more included infants who resettled themselves and those with long sleeps. Three-month olds fed solely breast milk were as likely to self-resettle or have long sleep bouts as infants fed formula or mixed breast and formula milk. Conclusions: Infants are capable of resettling themselves back to sleep in the first 3 months of age; both autonomous resettling and prolonged sleeping are involved in “sleeping through the night” at an early age. Findings indicate the need for physiological studies of how arousal, waking, and resettling develop into sustained sleeping and of how environmental factors support these endogenous and behavioral processes