197 research outputs found
Increases in ROPS Pricing from 2006-2012 and the Impact on ROPS Demand
In 2006, a social marketing campaign was developed to increase the installation of rollover protective structures (ROPS) on unprotected New York tractors. Using data gathered from the program\u27s hotline, the impact of price increases on farmers\u27 interest in ROPS is examined. Pricing data were obtained for all rigid ROPS kits commercially available in the U.S. since 2006. These data were stratified into two groups of ROPS suppliers: (1) tractor manufacturers that sell ROPS for their own tractors, referred to in this study as original equipment manufacturers (OEMs), and (2) aftermarket (AM) ROPS suppliers. The trend in price increases was contrasted with the change in the consumer price index (CPI), the probability of retrofitting within quintiles of cost was estimated, and the increase in ROPS prices over time was plotted The average price increase for a ROPS kit (excluding shipping and installation) over the six years of the study was 23.3% for OEM versus 60.5% for AM (p \u3c 0.0001). Out-of-pocket expenses held steady for OEM versus a six-year increase of $203 for AM (p = 0.098). The probability of a farmer retrofitting dropped monotonically from 66.9% in the lowest ROPS cost quintile to 23% in the highest. If these trends continue, the proportion of inquiries resulting in a ROPS retrofit will fall below 20% by 2020 for AM ROPS. Based on other trends identified in the literature, it is reasonable to assume that decreases in ROPS installation are likely to affect the tractor owners who are most likely to need these safety devices
The Hubble PanCET program: Transit and Eclipse Spectroscopy of the Hot-Jupiter WASP-74b
Planets are like children with each one being unique and special. A better understanding of their collective properties requires a deeper understanding of each planet. Here we add the transit and eclipse spectra of hot-Jupiter WASP-74b into the ever growing data set of exoplanet atmosphere spectral library. With six transits and three eclipses using the Hubble Space Telescope and Spitzer Space Telescope (Spitzer), we present the most complete and precise atmospheric spectra of WASP-74b. We found no evidence for TiO/VO nor super-Rayleigh scattering reported in previous studies. The transit shows a muted water feature with strong Rayleigh scattering extending into the infrared. The eclipse shows a featureless blackbody-like WFC3/G141 spectrum and a weak methane absorption feature in the Spitzer 3.6 μm band. Future James Webb Space Telescope follow-up observations are needed to confirm these results
Characterizing college science instruction: The Three-Dimensional Learning Observation Protocol
The importance of improving STEM education is of perennial interest, and to this end, the education community needs ways to characterize transformation efforts. Three-dimensional learning (3DL) is one such approach to transformation, in which core ideas of the discipline, scientific practices, and crosscutting concepts are combined to support student development of disciplinary expertise. We have previously reported on an approach to the characterization of assessments, the Three-Dimensional Learning Assessment Protocol (3D-LAP), that can be used to identify whether assessments have the potential to engage students in 3DL. Here we present the development of a companion, the Three-Dimensional Learning Observation Protocol (3D-LOP), an observation protocol that can reliably distinguish between instruction that has potential for engagement with 3DL and instruction that does not. The 3D-LOP goes beyond other observation protocols, because it is intended not only to characterize the pedagogical approaches being used in the instructional environment, but also to identify whether students are being asked to engage with scientific practices, core ideas, and crosscutting concepts. We demonstrate herein that the 3D-LOP can be used reliably to code for the presence of 3DL; further, we present data that show the utility of the 3D-LOP in differentiating between instruction that has the potential to promote 3DL from instruction that does not. Our team plans to continue using this protocol to evaluate outcomes of instructional transformation projects. We also propose that the 3D-LOP can be used to support practitioners in developing curricular materials and selecting instructional strategies to promote engagement in three-dimensional instruction
Depressed mood in pregnancy: Prevalence and correlates in two Cape Town peri-urban settlements
<p>Abstract</p> <p>Background</p> <p>The disability associated with depression and its impact on maternal and child health has important implications for public health policy. While the prevalence of postnatal depression is high, there are no prevalence data on antenatal depression in South Africa. The purpose of this study was to determine the prevalence and correlates of depressed mood in pregnancy in Cape Town peri-urban settlements.</p> <p>Methods</p> <p>This study reports on baseline data collected from the Philani Mentor Mothers Project (PMMP), a community-based, cluster-randomized controlled trial on the outskirts of Cape Town, South Africa. The PMMP aims to evaluate the effectiveness of a home-based intervention for preventing and managing illnesses related to HIV, TB, alcohol use and malnutrition in pregnant mothers and their infants. Participants were 1062 pregnant women from Khayelitsha and Mfuleni, Cape Town. Measures included the Edinburgh Postnatal Depression Scale (EPDS), the Derived AUDIT-C, indices for social support with regards to partner and parents, and questions concerning socio-demographics, intimate partner violence, and the current pregnancy. Data were analysed using bivariate analyses followed by logistic regression.</p> <p>Results</p> <p>Depressed mood in pregnancy was reported by 39% of mothers. The strongest predictors of depressed mood were lack of partner support, intimate partner violence, having a household income below R2000 per month, and younger age.</p> <p>Conclusions</p> <p>The high prevalence of depressed mood in pregnancy necessitates early screening and intervention in primary health care and antenatal settings for depression. The effectiveness and scalability of community-based interventions for maternal depression must be developed for pregnant women in peri-urban settlements.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00972699">NCT00972699</a>.</p
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
Intrusive Traumatic Re-Experiencing Domain (ITRED) – Functional Connectivity Feature Classification by the ENIGMA PTSD Consortium
Background
Intrusive Traumatic Re-Experiencing Domain (ITRED) was recently introduced as a novel perspective on posttraumatic psychopathology, proposing to focus research of posttraumatic stress disorder (PTSD) on the unique symptoms of intrusive and involuntary re-experiencing of the trauma, namely, intrusive memories, nightmares, and flashbacks. The aim of the present study was to explore ITRED from a neural network connectivity perspective.
Methods
Data was collected from nine sites taking part in the ENIGMA-PTSD Consortium (n=584) and included itemized PTSD symptoms scores and resting-state functional connectivity (rsFC) data. We assessed the utility of rsFC in classifying PTSD, ITRED-only (no PTSD diagnosis), and Trauma-exposed (TE)-only (no PTSD or ITRED) groups using a machine learning approach, examining well-known networks implicated in PTSD. Random forest classification model was built on a training set using cross-validation (CV), and the averaged CV model performance for classification was evaluated using area-under-the-curve (AUC). The model was tested using a fully independent portion of the data (test dataset), and the test AUC was evaluated.
Results
RsFC signatures differentiated TE-only participants from PTSD and from ITRED-only participants at about 60% accuracy. Conversely, rsFC signatures did not differentiate PTSD from ITRED-only individuals (45% accuracy). Common features differentiating TE-only participants from PTSD and from ITRED-only participants mainly involved default mode network-related pathways. Some unique features, such as connectivity within the frontal-parietal network, differentiated TE-only participants from one group (PTSD or ITRED-only), but to a lesser extent from the other.
Conclusion
Neural network connectivity supports ITRED as a novel neurobiologically-based approach to classifying post-trauma psychopathology
JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b
Clouds are prevalent in many of the exoplanet atmospheres that have been
observed to date. For transiting exoplanets, we know if clouds are present
because they mute spectral features and cause wavelength-dependent scattering.
While the exact composition of these clouds is largely unknown, this
information is vital to understanding the chemistry and energy budget of
planetary atmospheres. In this work, we observe one transit of the hot Jupiter
WASP-17b with JWST's MIRI LRS and generate a transmission spectrum from 5-12
m. These wavelengths allow us to probe absorption due to the
vibrational modes of various predicted cloud species. Our transmission spectrum
shows additional opacity centered at 8.6 m, and detailed atmospheric
modeling and retrievals identify this feature as SiO(s) (quartz) clouds.
The SiO(s) clouds model is preferred at 3.5-4.2 versus a cloud-free
model and at 2.6 versus a generic aerosol prescription. We find the
SiO(s) clouds are comprised of small m particles,
which extend to high altitudes in the atmosphere. The atmosphere also shows a
depletion of HO, a finding consistent with the formation of
high-temperature aerosols from oxygen-rich species. This work is part of a
series of studies by our JWST Telescope Scientist Team (JWST-TST), in which we
will use Guaranteed Time Observations to perform Deep Reconnaissance of
Exoplanet Atmospheres through Multi-instrument Spectroscopy (DREAMS).Comment: 19 pages, 7 figures, accepted for publication in ApJ
Short Telomeres Compromise β-Cell Signaling and Survival
The genetic factors that underlie the increasing incidence of diabetes with age are poorly understood. We examined whether telomere length, which is inherited and known to shorten with age, plays a role in the age-dependent increased incidence of diabetes. We show that in mice with short telomeres, insulin secretion is impaired and leads to glucose intolerance despite the presence of an intact β-cell mass. In ex vivo studies, short telomeres induced cell-autonomous defects in β-cells including reduced mitochondrial membrane hyperpolarization and Ca2+ influx which limited insulin release. To examine the mechanism, we looked for evidence of apoptosis but found no baseline increase in β-cells with short telomeres. However, there was evidence of all the hallmarks of senescence including slower proliferation of β-cells and accumulation of p16INK4a. Specifically, we identified gene expression changes in pathways which are essential for Ca2+-mediated exocytosis. We also show that telomere length is additive to the damaging effect of endoplasmic reticulum stress which occurs in the late stages of type 2 diabetes. This additive effect manifests as more severe hyperglycemia in Akita mice with short telomeres which had a profound loss of β-cell mass and increased β-cell apoptosis. Our data indicate that short telomeres can affect β-cell metabolism even in the presence of intact β-cell number, thus identifying a novel mechanism of telomere-mediated disease. They implicate telomere length as a determinant of β-cell function and diabetes pathogenesis
Project Masihambisane: a cluster randomised controlled trial with peer mentors to improve outcomes for pregnant mothers living with HIV
Abstract Background Pregnant women living with HIV (WLH) face daily challenges maintaining their own and their babies' health and mental health. Standard Prevention of Maternal to Child Transmission (PMTCT) programs are not designed to address these challenges. Methods/Design As part of a cluster randomized controlled trial, WLH are invited to attend four antenatal and four postnatal small group sessions led by a peer WLH (a Peer Mentor). The WLH and their babies are assessed during pregnancy and at one week, six months, and twelve months post-birth. Mobile phones are used to collect routine information, complete questionnaires and remain in contact with participants over time. Pregnant WLH (N = 1200) are randomly assigned by clinic (N = 8 clinics) to an intervention program, called Masihambisane (n = 4 clinics, n = 600 WLH) or a standard care PMTCT control condition (n = 4 clinics; n = 600 WLH). Discussion Data collection with cellular phones are innovative and effective in low-resource settings. Standard PMTCT programs are not designed to address the daily challenges faced by WLH; Peer Mentors may be useful in supporting WLH to cope with these challenges. Trial registration ClinicalTrials.gov registration # NCT0097269
Pathogenic SPTBN1 variants cause an autosomal dominant neurodevelopmental syndrome
SPTBN1 mutations cause a neurodevelopmental syndrome characterized by intellectual disability, language and motor delays, autism, seizures and other features. The variants disrupt beta II-spectrin function and disturb cytoskeletal organization and dynamics. SPTBN1 encodes beta II-spectrin, the ubiquitously expressed beta-spectrin that forms micrometer-scale networks associated with plasma membranes. Mice deficient in neuronal beta II-spectrin have defects in cortical organization, developmental delay and behavioral deficiencies. These phenotypes, while less severe, are observed in haploinsufficient animals, suggesting that individuals carrying heterozygous SPTBN1 variants may also show measurable compromise of neural development and function. Here we identify heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays;mild to severe intellectual disability;autistic features;seizures;behavioral and movement abnormalities;hypotonia;and variable dysmorphic facial features. We show that these SPTBN1 variants lead to effects that affect beta II-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. Our studies define SPTBN1 variants as the genetic basis of a neurodevelopmental syndrome, expand the set of spectrinopathies affecting the brain and underscore the critical role of beta II-spectrin in the central nervous system
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