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Autonomic nervous system functioning assessed during the Still-Face Paradigm: A meta-analysis and systematic review of methods, approach and findings.
Animal and human research suggests that the development of the autonomic nervous system (ANS) is particularly sensitive to early parenting experiences. The Still-Face Paradigm (SFP), one of the most widely used measures to assess infant reactivity and emotional competence, evokes infant self-regulatory responses to parental interaction and disengagement. This systematic review of 33 peer-reviewed studies identifies patterns of parasympathetic (PNS) and sympathetic (SNS) nervous system activity demonstrated by infants under one year of age during the SFP and describes findings within the context of sample demographic characteristics, study methodologies, and analyses conducted. A meta-analysis of a subset of 14 studies with sufficient available respiratory sinus arrhythmia (RSA) data examined whether the SFP reliably elicited PNS withdrawal (RSA decrease) during parental disengagement or PNS recovery (RSA increase) during reunion, and whether results differed by socioeconomic status (SES). Across SES, the meta-analysis confirmed that RSA decreased during the still-face episode and increased during reunion. When studies were stratified by SES, low-SES or high-risk groups also showed RSA decreases during the still face episode but failed to show an increase in RSA during reunion. Few studies have examined SNS activity during the SFP to date, preventing conclusions in that domain. The review also identified multiple qualifications to patterns of SFP ANS findings, including those that differed by ethnicity, infant sex, parental sensitivity, and genetics. Strengths and weaknesses in the extant research that may explain some of the variation in findings across the literature are also discussed, and suggestions for strengthening future research are provided
The discovery of very red counterparts to faint X-ray sources
We present deep K-band imaging at the positions of four very faint X-ray
sources found in the UK ROSAT Deep Survey to have no optical counterpart
brighter than R~23. Likely identifications are found within the ROSAT error
circle in all four fields with R-K colours of between 3.2 +/- 0.4 and 6.4 +/-
0.6. From a consideration of the R-K colours and X-ray to optical luminosity
ratios of the candidate identifications, we tentatively classify two of the
X-ray sources as very distant (z ~ 1) clusters of galaxies, one as a narrow
emission line galaxy and one as an obscured QSO.Comment: 7 pages, LaTeX, 7 figures (1 postscript file each). Uses mn.sty and
epsf.sty. Accepted by MNRAS. For more information see
http://www.astro.soton.ac.uk/~amn/UKdee
The strategic integration of agile and lean supply
Lean supply is closely associated with enabling flow and the elimination of wasteful variation within the supply chain. However, lean operations depend on level scheduling and the growing need to accommodate variety and demand uncertainty has resulted in the emergence of the concept of agility. This paper explores the role of inventory and capacity in accommodating such variation and identifies how TRIZ separation principles and TOC tools may be combined in the integrated development of responsive and efficient supply chains. A detailed apparel industry case study is used to illustrate the application of these concepts and tools
Automated Impact Assessment: A New Approach to ISS Payload Operations Anomaly Response
The International Space Station (ISS) Payload Operations and Integration Center (POIC) is undergoing rapid growth as the space station program focuses on science and commercial activities. The ISS is expanding its onboard capabilities to support additional science activities. In parallel, the POIC is expanding the capabilities of our operations tools to support the higher pace of payload activities being executed each week. An effect of these changes is that anomaly resolution has become more challenging. In the event of a real-time system fault, operators are responsible for analyzing telemetry displays, anomaly monitoring tools, documentation, and system models in order to produce failure impacts and recovery strategies. This approach to operations relies on the operator to ingest, process, and analyze information from an array of deterministic sources to provide actionable data on impacted systems and activities. Changing the existing approach of anomaly response is necessary if the ISS community is to succeed in the age of science and commercialization of space. The creation of a tool that captures deterministic technical systems knowledge and integrates existing telemetry, documentation, and planning information will allow the burden of impact assessment to be automated, thereby allowing the operator to focus on non-deterministic tasks, such as recovering failed systems and restoring critical payload operations
What Does an Exemplary Middle School Mathematics Teacher Look Like? The Use of a Professional Development Rubric
A School University Research Network (SURN) committee composed of current mathematics teachers, central office math supervisors, building administrators, mathematicians, and mathematics educators researched numerous sources regarding best practices in mathematics instruction. The resulting professional development rubric synthesizes their findings and can serve a professional development role by providing teachers and administrators with a tool to develop clarity and consensus on best mathematics instructional practices, and how these practices are implemented in the classroom. It is also being used as a tool for cooperating teachers in their supervision of student teachers and as a reflective method for self-evaluation
Physical and biological controls on fine sediment transport and storage in rivers
Excess fine sediment, comprising particles <2 mm in diameter, is a major cause of ecological degradation in rivers. The erosion of fine sediment from terrestrial or aquatic sources, its delivery to the river, and its storage and transport in the fluvial environment are controlled by a complex interplay of physical, biological and anthropogenic factors. Whilst the physical controls exerted on fine sediment dynamics are relatively well-documented, the role of biological processes and their interactions with hydraulic and physico-chemical phenomena has been largely overlooked. The activities of biota, from primary producers to predators, exert strong controls on fine sediment deposition, infiltration and resuspension. For example, extracellular polymeric substances (EPS) associated with biofilms increase deposition and decrease resuspension. In lower energy rivers, aquatic macrophyte growth and senescence are intimately linked to sediment retention and loss, whereas riparian trees are dominant ecosystem engineers in high energy systems. Fish and invertebrates also have profound effects on fine sediment dynamics through activities that drive both particle deposition and erosion depending on species composition and abiotic conditions. The functional traits of species present will determine not only these biotic effects but also the responses of river ecosystems to excess fine sediment. We discuss which traits are involved and put them into context with spatial processes that occur throughout the river network. Whilst strides towards better understanding of the impacts of excess fine sediment have been made, further progress to identify the most effective management approaches is urgently required through close communication between authorities and scientists
Dynamic communities in multichannel data: An application to the foreign exchange market during the 2007--2008 credit crisis
We study the cluster dynamics of multichannel (multivariate) time series by
representing their correlations as time-dependent networks and investigating
the evolution of network communities. We employ a node-centric approach that
allows us to track the effects of the community evolution on the functional
roles of individual nodes without having to track entire communities. As an
example, we consider a foreign exchange market network in which each node
represents an exchange rate and each edge represents a time-dependent
correlation between the rates. We study the period 2005-2008, which includes
the recent credit and liquidity crisis. Using dynamical community detection, we
find that exchange rates that are strongly attached to their community are
persistently grouped with the same set of rates, whereas exchange rates that
are important for the transfer of information tend to be positioned on the
edges of communities. Our analysis successfully uncovers major trading changes
that occurred in the market during the credit crisis.Comment: 8 pages, 6 figures, accepted for publication in Chao
Competition Between Antiferromagnetic Order and Spin-Liquid Behavior in the Two-Dimensional Periodic Anderson Model at Half-Filling
We study the two-dimensional periodic Anderson model at half-filling using
quantum Monte Carlo (QMC) techniques. The ground state undergoes a magnetic
order-disorder transition as a function of the effective exchange coupling
between the conduction and localized bands. Low-lying spin and charge
excitations are determined using the maximum entropy method to analytically
continue the QMC data. At finite temperature we find a competition between the
Kondo effect and antiferromagnetic order which develops in the localized band
through Ruderman-Kittel-Kasuya-Yosida interactions.Comment: Revtex 3.0, 10 pages + 5 figures, UCSBTH-94-2
Partial CMB maps: bias removal and optimal binning of the angular power spectrum
We present a semi-analytical method to investigate the systematic effects and
statistical uncertainties of the calculated angular power spectrum when
incomplete spherical maps are used. The computed power spectrum suffers in
particular a loss of angular frequency resolution, which can be written as
\delta_l ~ \pi/\gamma_max, where \gamma_max is the effective maximum extent of
the partial spherical maps. We propose a correction algorithm to reduce
systematic effects on the estimated C_l, as obtained from the partial map
projection on the spherical harmonic Ylm(l,m) basis. We have derived near
optimal bands and weighting functions in l-space for power spectrum calculation
using small maps, and a correction algorithm for partially masked spherical
maps that contain information on the angular correlations on all scales.Comment: 11 page
First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon
We present the first results of the KMOS Lens-Amplified Spectroscopic Survey
(KLASS), a new ESO Very Large Telescope (VLT) large program, doing multi-object
integral field spectroscopy of galaxies gravitationally lensed behind seven
galaxy clusters selected from the HST Grism Lens-Amplified Survey from Space
(GLASS). Using the power of the cluster magnification we are able to reveal the
kinematic structure of 25 galaxies at , in four
cluster fields, with stellar masses . This sample includes 5 sources at with lower stellar masses
than in any previous kinematic IFU surveys. Our sample displays a diversity in
kinematic structure over this mass and redshift range. The majority of our
kinematically resolved sample is rotationally supported, but with a lower ratio
of rotational velocity to velocity dispersion than in the local universe,
indicating the fraction of dynamically hot disks changes with cosmic time. We
find no galaxies with stellar mass in our sample
display regular ordered rotation. Using the enhanced spatial resolution from
lensing, we resolve a lower number of dispersion dominated systems compared to
field surveys, competitive with findings from surveys using adaptive optics. We
find that the KMOS IFUs recover emission line flux from HST grism-selected
objects more faithfully than slit spectrographs. With artificial slits we
estimate slit spectrographs miss on average 60% of the total flux of emission
lines, which decreases rapidly if the emission line is spatially offset from
the continuum.Comment: Accepted for publication in Ap
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