6,612 research outputs found
From Teasing to Torment: School Climate Revisited - A Survey of U.S. Secondary School Students and Teachers
From Teasing to Torment: School Climate Revisited, A Survey of U.S. Secondary School Students and Teachers provides an in-depth look at the current landscape of bias and peer victimization as reported by students and teachers from across the nation. In addition to examining various types of bias, including those based on race/ethnicity, religion, body size, and ability, this report provides a focused look at LGBTQ issues in secondary schools. Comparing findings to a similar survey we conducted in 2005, the report discusses the progress that has been made over the past ten years, as well as highlights the challenges that remain. It also offers recommendations and strategies to improve school climate for all students.Specifically, the research report addresses:Student and teacher perceptions of school climate; Student experiences of safety, bullying, and harassment, including biased incidents based on race/ethnicity, sexual orientation, body size, gender, religion, ability, economic status, and gender expression;Teacher intervention in bullying and incidents of bias; LGBT-supportive teacher practices, such as advising GSA or including LGBT content in teaching;Teacher professional development (pre-service and in-service) in bullying, diversity, and LGBT issues; andDifferences in students' school experiences based on race/ethnicity, LGBTQ status, gender nonconformity, and geography (i.e., urbanicity, region), among others
From Teasing to Torment: School Climate Revisited - A Survey of U.S. Secondary School Students and Teachers, Executive Summary
From Teasing to Torment: School Climate Revisited, A Survey of U.S. Secondary School Students and Teachers affords us the opportunity to document the current state of safety, bias, and bullying in schools and assess potential disparities based not only on LGBTQ status, but also on race/ethnicity, sex, gender expression, and socioeconomic status. As school climate is determined not only by the existence or absence of victimization, we also explore students' experiences with school disciplinary actions and extracurricular activities, seeking to develop a more complete picture of the student experience. In addition, we again document students' access to resources that may improve school climate, such as student clubs that address LGBTQ student issues, inclusive curriculum, and anti-bullying/harassment policies. Moreover, in this report, secondary school teachers offer their perceptions on bias, bullying, and LGBTQ students' safety, and provide valuable information about the preparation they may have received to address these issues. We also document teachers' practices in regards to combating bias and supporting LGBTQ students specifically, including the potential barriers to doing so. Lastly, we offer recommendations for both further research and specific programmatic and policy strategies that may help schools reduce the risk of peer victimization, counter the damaging effects of bias, and provide safe and supportive learning environments for all LGBTQ and non-LGBTQ students alike
CMB Constraints on Primordial non-Gaussianity from the Bispectrum (f_{NL}) and Trispectrum (g_{NL} and \tau_{NL}) and a New Consistency Test of Single-Field Inflation
We outline the expected constraints on non-Gaussianity from the cosmic
microwave background (CMB) with current and future experiments, focusing on
both the third (f_{NL}) and fourth-order (g_{NL} and \tau_{NL}) amplitudes of
the local configuration or non-Gaussianity. The experimental focus is the
skewness (two-to-one) and kurtosis (two-to-two and three-to-one) power spectra
from weighted maps. In adition to a measurement of \tau_{NL} and g_{NL} with
WMAP 5-year data, our study provides the first forecasts for future constraints
on g_{NL}. We describe how these statistics can be corrected for the mask and
cut-sky through a window function, bypassing the need to compute linear terms
that were introduced for the previous-generation non-Gaussianity statistics,
such as the skewness estimator. We discus the ratio A_{NL} =
\tau_{NL}/(6f_{NL}/5)^2 as an additional test of single-field inflationary
models and discuss the physical significance of each statistic. Using these
estimators with WMAP 5-Year V+W-band data out to l_{max}=600 we constrain the
cubic order non-Gaussianity parameters \tau_{NL}, and g_{NL} and find -7.4 <
g_{NL}/10^5 < 8.2 and -0.6 < \tau_{NL}/10^4 < 3.3 improving the previous
COBE-based limit on \tau_{NL} < 10^8 nearly four orders of magnitude with WMAP.Comment: 15 pages. 14 figure
Design and simulation of a mobile robot platform for navigation and obstacle detection
Mobile platforms are expected to gain access to risk zones and hazardous environment. A typical example is the infectious disease environment to deliver items to a sick patient. The robot is aimed to manoeuver round flat grounds in indoor environment. Computer aided design (CAD) models of the selected concepts were developed in Fusion360 and imported into SolidWorks to optimize and improve the design. The design is focused on the development of the wheelbase. Arduino Microcontroller was the system and codes control board and it was developed using the Arduino software. The motor driver was used to drive the DC motor for robot navigation with ultrasonic sensor for obstacle detection at a range of 20 cm. Result shows that the robot was able to navigate round flat ground while detecting obstacles within 20 cm
New Methods for Measurements of Photosynthesis from Space
Our ability to close the Earth's carbon budget and predict feedbacks in a warming climate
depends critically on knowing where, when, and how carbon dioxide (CO2) is exchanged
between the land and atmosphere. In particular, determining the rate of carbon fixation by
the Earth's biosphere (commonly referred to as gross primary productivity, or GPP) and the
dependence of this productivity on climate is a central goal. Historically, GPP has been
inferred from spectral imagery of the land and ocean. Assessment of GPP from the color of
the land and ocean requires, however, additional knowledge of the types of plants in the
scene, their regulatory mechanisms, and climate variables such as soil moistureâjust the
independent variables of interest!
Sunlight absorbed by chlorophyll in photosynthetic organisms is mostly used to drive
photosynthesis, but some can also be dissipated as heat or reâradiated at longer wavelengths
(660â800 nm). This nearâinfrared light reâemitted from illuminated plants is termed solarinduced
fluorescence (SIF), and it has been found to strongly correlate with GPP. To advance
our understanding of SIF and its relation to GPP and environmental stress at the planetary
scale, the Keck Institute for Space Studies (KISS) convened a workshopâheld in Pasadena,
California, in August 2012âto focus on a newly developed capacity to monitor chlorophyll
fluorescence from terrestrial vegetation by satellite. This revolutionary approach for
retrieving global observations of SIF promises to provide direct and spatially resolved
information on GPP, an ideal bottomâup complement to the atmospheric net CO2 exchange
inversions.
Workshop participants leveraged our efforts on previous studies and workshops related to
the European Space Agencyâs FLuorescence EXplorer (FLEX) mission concept, which had
already targeted SIF for a possible satellite mission and had developed a vibrant research
community with many important publications. These studies, mostly focused on landscape,
canopy, and leafâlevel interpretation, provided the groundâwork for the workshop, which
focused on the global carbon cycle and synergies with atmospheric net flux inversions.
Workshop participants included key members of several communities: plant physiologists
with experience using active fluorescence methods to quantify photosynthesis; ecologists
and radiative transfer experts who are studying the challenge of scaling from the leaf to
regional scales; atmospheric scientists with experience retrieving photometric information
from spaceâborne spectrometers; and carbon cycle experts who are integrating new
observations into models that describe the exchange of carbon between the atmosphere,
land and ocean. Together, the participants examined the link between âpassiveâ fluorescence
observed from orbiting spacecraft and the underlying photochemistry, plant physiology and
biogeochemistry of the land and ocean.
This report details the opportunity for forging a deep connection between scientists doing
basic research in photosynthetic mechanisms and the more applied community doing
research on the Earth System. Too often these connections have gotten lost in empiricism
associated with the coarse scale of global models. Chlorophyll fluorescence has been a major
tool for basic research in photosynthesis for nearly a century. SIF observations from space,
although sensing a large footprint, probe molecular events occurring in the leaves below.
This offers an opportunity for direct mechanistic insight that is unparalleled for studies of
biology in the Earth System.
A major focus of the workshop was to review the basic mechanisms that underlie this
phenomenon, and to explore modeling tools that have been developed to link the biophysical
and biochemical knowledge of photosynthesis with the observableâin this case, the
radiance of SIFâseen by the satellite. Discussions led to the identification of areas where
knowledge is still lacking. For example, the inability to do controlled illumination
observations from space limits the ability to fully constrain the variables that link
fluorescence and photosynthesis.
Another focus of the workshop explored a âtopâdownâ view of the SIF signal from space.
Early studies clearly identified a strong correlation between the strength of this signal and
our best estimate of the rate of photosynthesis (GPP) over the globe. New studies show that
this observation provides improvements over conventional reflectanceâbased remote
sensing in detecting seasonal and environmental (particularly drought related) modulation
of photosynthesis. Apparently SIF responds much more quickly and with greater dynamic
range than typical greenness indices when GPP is perturbed. However, discussions at the
workshop also identified areas where topâdown analysis seemed to be âout in frontâ of
mechanistic studies. For example, changes in SIF based on changes in canopy light
interception and the light use efficiency of the canopy, both of which occur in response to
drought, are assumed equivalent in the topâdown analysis, but the mechanistic justification
for this is still lacking from the bottomâup side.
Workshop participants considered implications of these mechanistic and empirical insights
for largeâscale models of the carbon cycle and biogeochemistry, and also made progress
toward incorporating SIF as a simulated output in land surface models used in global and
regionalâscale analysis of the carbon cycle. Comparison of remotely sensed SIF with modelsimulated
SIF may open new possibilities for model evaluation and data assimilation,
perhaps leading to better modeling tools for analysis of the other retrieval from GOSAT
satellite, atmospheric CO2 concentration. Participants also identified another application for
SIF: a linkage to the physical climate system arising from the ability to better identify
regional development of plant water stress. Decreases in transpiration over large areas of a
continent are implicated in the development and âlockingâinâ of drought conditions. These
discussions also identified areas where current land surface models need to be improved in
order to enable this research. Specifically, the radiation transport treatments need dramatic
overhauls to correctly simulate SIF.
Finally, workshop participants explored approaches for retrieval of SIF from satellite and
groundâbased sensors. The difficulty of resolving SIF from the overwhelming flux of reflected
sunlight in the spectral region where fluorescence occurs was once a major impediment to
making this measurement. Placement of very high spectral resolution spectrometers on
GOSAT (and other greenhouse gasâsensing satellites) has enabled retrievals based on infilling
of solar Fraunhofer lines, enabling accurate fluorescence measurements even in the
presence of moderately thick clouds. Perhaps the most interesting challenge here is that
there is no readily portable groundâbased instrumentation that even approaches the
capability of GOSAT and other planned greenhouse gas satellites. This strongly limits scientistsâ ability to conduct groundâbased studies to characterize the footprint of the GOSAT
measurement and to conduct studies of radiation transport needed to interpret SIF
measurement.
The workshop results represent a snapshot of the state of knowledge in this area. New
research activities have sprung from the deliberations during the workshop, with
publications to follow. The introduction of this new measurement technology to a wide slice
of the community of Earth System Scientists will help them understand how this new
technology could help solve problems in their research, address concerns about the
interpretation, identify future research needs, and elicit support of the wider community for
research needed to support this observation.
Somewhat analogous to the original discovery that vegetation indices could be derived from
satellite measurements originally intended to detect clouds, the GOSAT observations are a
rare case in which a (fortuitous) global satellite dataset becomes available before the
research community had a consolidated understanding on how (beyond an empirical
correlation) it could be applied to understanding the underlying processes. Vegetation
indices have since changed the way we see the global biosphere, and the workshop
participants envision that fluorescence can perform the next indispensable step by
complementing these measurements with independent estimates that are more indicative of
actual (as opposed to potential) photosynthesis. Apart from the potential FLEX mission, no
dedicated satellite missions are currently planned. OCOâ2 and â3 will provide much more
data than GOSAT, but will still not allow for regional studies due to the lack of mapping
capabilities. Geostationary observations may even prove most useful, as they could track
fluorescence over the course of the day and clearly identify stressârelated downâregulation of
photosynthesis. Retrieval of fluorescence on the global scale should be recognized as a
valuable tool; it can bring the same quantum leap in our understanding of the global carbon
cycle as vegetation indices once did
Spatial processing is frequency-specific in auditory cortex but not in the midbrain
The cochlea behaves like a bank of band-pass filters, segregating information into different frequency channels. Some aspects of perception reflect processing within individual channels, but others involve the integration of information across them. One instance of this is sound localization, which improves with increasing bandwidth. The processing of binaural cues for sound location has been extensively studied. However, while the advantage conferred by bandwidth is clear we currently know little about how this additional information is combined to form our percept of space. We investigated the ability of cells in the auditory system of guinea pigs to compare interaural level differences (ILDs), a key localization cue, between tones of disparate frequencies in each ear. Cells in auditory cortex, believed to be integral to ILD processing (Excitatory from one ear, Inhibitory from the other: EI cells), separately compare ILDs over restricted frequency ranges, not consistent with their monaural tuning. In contrast, cortical EE (Excitatory from both ears) cells showed no evidence of frequency-specific processing. Both cell types are explained by a model in which ILDs are computed within separate frequency channels and subsequently combined in a single cortical cell. Interestingly, ILD processing in all inferior colliculus cell types (EE and EI) is largely consistent with processing within single matched frequency channels from each ear. Our data suggests a clear constraint on the way that localisation cues are integrated: cortical ILD tuning to broadband sounds is a composite of separate frequency-specific binaurally sensitive channels. This frequency-specific processing appears after the midbrain
A review on humanoid robotics in healthcare
Humanoid robots have evolved over the years and today it is in many different areas of applications, from homecare to social care and healthcare robotics. This paper deals with a brief overview of the current and potential applications of humanoid robotics in healthcare settings. We present a comprehensive contextualization of humanoid robots in healthcare by identifying and characterizing active research activities on humanoid robot that can work interactively and effectively with humans so as to fill some identified gaps in current healthcare deficiency
Variants within protectin (CD59) and CD44 genes linked to an inherited haplotype in a family with coeliac disease
Coeliac disease (CD) is an autoimmune disorder characterised by inflammation, villous atrophy and hyperplasia of the small intestinal mucosa that affects genetically susceptible individuals. A genome-wide scan was performed in 17 family members with high incidence of CD. Highest nonparametric linkage (NPL) and logarithm of odds (LOD) scores were of 6.21 (P = 0.0107) and 2.57, respectively, to a region on chromosome 11p13-12. Following fine mapping, NPL and LOD scores did not change, but the linkage interval on chromosome 11 was narrowed to a region that is approximately 50.94 cM from pTer. Two inherited haplotypes on chromosomes 11p13-12 and 9q21 were observed in all affected members but not in the majority of clinically normal individuals. Sequencing of genes at region 11p13-12 showed a number of sequence variants, two of which were linked with the inherited haplotype. One of these variants in the CD59 gene was found at a very low frequency in the population and could possibly affect pre-messenger RNA splicing. This study is of particular importance for the identification of novel genes that might be responsible for CD other than human leukocyte antigen.peer-reviewe
Fused Deposition Modeling Printed Patterns for Sand Casting in a Nigerian Foundry: A Review
There has been a gradual adoption of Three-Dimensional (3D)
printing in pattern making for sand casting absolutely because of its reduced lead-time and higher dimensional accuracy.Pattern making is the most central activity in the production line of any casting operation. A delay in pattern making or a defect in pattern usually translates to increased production cost and time or poor quality castings respectively. Many foundry industries have been concerned with reducing the duration for pattern making and improving the dimensional accuracy of patterns. Adoption of Fused Deposition Modeling (FDM) based patterns have only provided a limited solution to the challenges of traditional pattern making for sand casting.Some patterns are not suitable for FDM printing due to their size volume which is not usually cost-effective to print. Also,the surface quality and mechanical properties of patterns produced with FDM are usually affected by process parameters thereby leading to post-manufacturing treatment before the patterns are suitable for moulding operation. This study investigated the problems of traditional pattern making and the challenges of FDM-printed PLA-patterns for sand casting and suggested solutions and areas for future research. Related researches on 3D printing in the foundry carried out around the worldwide are discussed
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