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Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
Analysis and understanding of the role of hydrogen in metals is a significant challenge for the future of materials science, and this is a clear objective of recent work in the atom probe tomography (APT) community. Isotopic marking by deuteration has often been proposed as the preferred route to enable quantification of hydrogen by APT. Zircaloy-4 was charged electrochemically with hydrogen and deuterium under the same conditions to form large hydrides and deuterides. Our results from a Zr hydride and a Zr deuteride highlight the challenges associated with accurate quantification of hydrogen and deuterium, in particular associated with the overlap of peaks at a low mass-to-charge ratio and of hydrogen/deuterium containing molecular ions. We discuss possible ways to ensure that appropriate information is extracted from APT analysis of hydrogen in zirconium alloy systems that are important for nuclear power applications.
Atom probe tomography (APT) is rising in influence across many parts of materials science and engineering thanks to its unique combination of highly sensitive composition measurement and three-dimensional microstructural characterization. In this invited article, we have selected a few recent applications that showcase the unique capacity of APT to measure the local composition at structural defects. Whether we consider dislocations, stacking faults, or grain boundary, the detailed compositional measurements tend to indicate specific partitioning behaviors for the different solutes in both complex engineering and model alloys we investigated.
Plant nitrogen (N) links with many physiological progresses of crop growth and yield formation. Accurate simulation is key to predict crop growth and yield correctly. The aim of the current study was to improve the estimation of N uptake and translocation processes in the whole rice plant as well as within plant organs in the RiceGrow model by using plant and organ maximum, critical and minimum N dilution curves. The maximum and critical N (Nc) demand (obtained from the maximum and critical curves) of shoot and root and Nc demand of organs (leaf, stem and panicle) are calculated by N concentration and biomass. Nitrogen distribution among organs is computed differently pre- and post-anthesis. Pre-anthesis distribution is determined by maximum N demand with no priority among organs. In post-anthesis distribution, panicle demands are met first and then the remaining N is allocated to other organs without priority. The amount of plant N uptake depends on plant N demand and N supplied by the soil. Calibration and validation of the established model were performed on field experiments conducted in China and the Philippines with varied N rates and N split applications; results showed that this improved model can simulate the processes of N uptake and translocation well.
Using multilevel models, we examined mother-, father-, and child-reported (N = 1,336 families) externalizing behavior problem trajectories from age 7 to 14 in nine countries (China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States). The intercept and slope of children's externalizing behavior trajectories varied both across individuals within culture and across cultures, and the variance was larger at the individual level than at the culture level. Mothers’ and children's endorsement of aggression as well as mothers’ authoritarian attitudes predicted higher age 8 intercepts of child externalizing behaviors. Furthermore, prediction from individual-level endorsement of aggression and authoritarian attitudes to more child externalizing behaviors was augmented by prediction from cultural-level endorsement of aggression and authoritarian attitudes, respectively. Cultures in which father-reported endorsement of aggression was higher and both mother- and father-reported authoritarian attitudes were higher also reported more child externalizing behavior problems at age 8. Among fathers, greater attributions regarding uncontrollable success in caregiving situations were associated with steeper declines in externalizing over time. Understanding cultural-level as well as individual-level correlates of children's externalizing behavior offers potential insights into prevention and intervention efforts that can be more effectively targeted at individual children and parents as well as targeted at changing cultural norms that increase the risk of children's and adolescents’ externalizing behavior.
Pneumococcal serotype replacement is an important issue after the introduction of pneumococcal conjugate vaccine (PCV) in children. After the introduction of 13-valent PCV, the incidence of invasive pneumococcal diseases (IPD) caused by Streptococcus pneumoniae serotype 12F (Sp12F) have increased in some countries; however, an outbreak of Sp12F has not reported in the post-13-valent PCV era. We experienced a local outbreak of Sp12F during March through May 2016 in Tsuruoka city, Japan after the introduction of 13-valent PCV in 2013. The IPD patients were two children and seven adults, three of whom died with a rapid disease progress. Although the clear transmission route was not determined, eight of the nine patients (89%) had close contact with children, which suggests that transmitted colonisation of Sp12F among children and adults might be the source of transmission. Continuous monitoring of IPDs, along with the determination of pneumococcal serotypes, is warranted in the post–13-valent PCV era. New IPD control strategies may be needed if this fatal outbreak continues to occur.
OBJECTIVES/SPECIFIC AIMS: Gliomas are the most lethal and common
primary tumor type in the central nervous system across all age groups; affected
adults have a life expectancy of just 14 months. As glioma cells invade the
surrounding normal parenchyma they remodel the composition and ultrastructure of
the surrounding extracellular matrix (ECM), suggesting that the native (i.e.,
“normal”) microenvironment is not ideal for their survival
and proliferation. Recent reports describe suppressive and/or lethal
effects of mammalian ECM hydrogels derived from normal (nonneoplastic) sources
upon various cancer types. ECM-based bioscaffolds placed at sites of neoplastic
tissue resection in humans have never been reported to facilitate cancer
recurrence. The objective of the present research is to evaluate mammalian ECM
as a novel approach to glioma therapy. METHODS/STUDY POPULATION: ECM
hydrogels from porcine dermis, small intestine, and urinary bladder were
produced as described previously. Primary glioma cells were graciously supplied
by Drs. Nduka Amankulor and Johnathan Engh, and U-87 MG were ordered through
ATCC. Cells were plated onto tissue culture plastic at
~60% confluence and allowed to attach for 24 hours before
treatment. The saline-soluble fraction (SSF) of ECM was obtained by mixing
lyophilized, comminuted ECM with 0.9% saline for 24 hours then
filtering the resulting mixture through a 10 kDa molecular weight cutoff column.
All assays and kits were followed according to the manufacturer’s
instructions. Cell viability was measured via MTT assay
(Vybrant® MTT Cell Proliferation Assay, Invitrogen)
and by live/dead staining
(LIVE/DEAD® Cell Imaging Kit, Invitrogen). Time
lapse videos were created by taking images every 20 minutes for 18 hours
(phase-contrast) or every 10 minutes for 12 hours (darkfield). NucView reagent
was ordered from Biotium. Temozolomide was ordered through Abmole. All in vivo
work was conducted according to protocols approved by the University of
Pittsburgh’s IACUC office. RESULTS/ANTICIPATED RESULTS:
ECM hydrogels derived from porcine dermis, small intestine, or urinary bladder
all decreased the viability of primary glioma cells in vitro, with urinary
bladder extracellular matrix (UBM) having the most dramatic effects. The SSF of
UBM (UBM-SSF), devoid of the fibrillar, macromolecular components of ECM, was
sufficient to recapitulate this detrimental effect upon neoplastic cells in
vitro and was used for the remainder of the experiments described herein. In a
cell viability assay normalized to the media treatment, non-neoplastic CHME5 and
N1E-115 cells scored 103% and 114% after 48 hours when
treated with UBM-SSF and 2 primary high-grade glioma cell types scored
17% and 30.5% with UBM-SSF (n=2).
Phase-contrast time-lapse video showed CHME5 and HFF thriving in the presence of
UBM-SSF for 18 hours while most primary glioma cells shriveled and died within
this time. Darkfield time-lapse video of wells containing Nucview dye,
fluorescent upon cleavage by active caspase-3, confirmed that within 12 hours
most primary glioma cells underwent apoptosis while CHME5 and HFF did not. In
culture with primary astrocytes, high grade primary glioma cells, and U-87 MG
glioma cells for 24 hours, UBM-SSF was found to significantly increase the
population of primary astrocytes compared with media
(p<0.05) while decreasing the 2 glioma cell types to
approximately one-third as many cells as the media control
(p<0.0001). A dose-response of temozolomide from 0
to 10,000 μM showed that when treating 2 non-neoplastic cell types
(CHME5 and HFF) and 2 types of primary glioma cell there was no difference in
survivability at any concentration. Contrasted to this, a dose-response of
UBM-SSF from 350 to 7000 μg/mL showed that the
non-neoplastic cells survived significantly better than the glioma cells at
concentrations of 875 μg/mL and upward
(p<0.05). In preliminary animal experiments, large
primary glioma tumors in the flanks of athymic nude mice were resected and
replaced with either UBM SSF or Matrigel (an ECM product of neoplastic cell
origin). After 7 days the resection sites with UBM-SSF had little tumor regrowth
if any compared with the dramatic recurrence seen in the Matrigel injection
sites (n=2). In a separate survival study comparing PBS to UBM-SSF
injections in the flank-resection model, all animals given PBS had to be
sacrificed at 9, 11, and 11 days (n=3) whereas animals given UBM-SSF
were sacrificed at 15, 24, and 39 days (n=3), indicating a moderate
increase in survival due to the UBM-SSF. DISCUSSION/SIGNIFICANCE OF
IMPACT: Since the introduction of the pan-cytotoxic chemotherapeutic agent TMZ
in 2005, the standard of care for patients with glioblastoma multiforme has not
improved. These findings indicate that non-neoplastic ECM contains potent
bioactive regulators capable of abrogating malignancy. Our in vitro data suggest
these molecules appear to have no deleterious effect on non-neoplastic cells
while specifically inducing apoptosis in glioma cells. Our in vivo data suggest
that these molecules may be useful in delaying glioma recurrence, thus resulting
in extended lifespan. Delivering soluble fractions of ECM to a tumor site may
represent a novel approach to glioma therapy, sidestepping traditional cytotoxic
therapies in favor of utilizing putative endogenous anti-tumor pathways.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
Using data from 1,177 families in eight countries (Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States), we tested a conceptual model of direct effects of childhood family adversity on subsequent externalizing behaviors as well as indirect effects through psychological mediators. When children were 9 years old, mothers and fathers reported on financial difficulties and their use of corporal punishment, and children reported perceptions of their parents’ rejection. When children were 10 years old, they completed a computerized battery of tasks assessing reward sensitivity and impulse control and responded to questions about hypothetical social provocations to assess their hostile attributions and proclivity for aggressive responding. When children were 12 years old, they reported on their externalizing behavior. Multigroup structural equation models revealed that across all eight countries, childhood family adversity had direct effects on externalizing behaviors 3 years later, and childhood family adversity had indirect effects on externalizing behavior through psychological mediators. The findings suggest ways in which family-level adversity poses risk for children's subsequent development of problems at psychological and behavioral levels, situated within diverse cultural contexts.
In anticipation of the launch of the Earth Observing System (EOS) Terra, and the Aqua spacecraft in 1999 and 2000, respectively, efforts are ongoing to determine errors of satellite-derived snow-cover maps. EOS Moderate Resolution Imaging Spectrora-diometer (MODIS) and Advanced Microwave Scanning Radiometer-E (AMSR-E) snow-cover products will be produced. For this study we compare snow maps covering the same study areas in Canada and the United States, acquired from different sensors using different snow-mapping algorithms. Four locations are studied: (1) Saskatchewan, Canada; (2) New England (New Hampshire, Vermont and Massachusetts) and eastern New York; (3) central Idaho and western Montana; and (4) North and South Dakota. Snow maps were produced using a prototype MODIS snow-mapping algorithm from Landsat Thematic Mapper (TM) scenes of each study area at 30 m and when the TM data were degraded to 1 km resolution. U.S. National Operational Hydrologic Remote Sensing Center (NOHRSC) 1km resolution snow maps were also used, as were snow maps derived from 0.5° × 0.5° resolution Special Sensor Microwave Imager (SSM/I) data. A land-cover map derived from the International Geosphere-Biosphere Program land-cover map of North America was also registered to the scenes. The TM, NOHRSC and SSM/ I snow maps, and land-cover maps were compared digitally. In most cases, TM-derived maps show less snow cover than the NOHRSC and SSM/I maps because areas of incomplete snow cover in forests (e.g. tree canopies, branches and trunks) are seen in the TM data but not in the coarser-resolution maps which may map the areas as completely snow-covered. The snow maps generally agree with respect to the spatial variability of the snow cover. The 30 m resolutionTM data provide the most accurate snow maps, and are thus used as the baseline for comparison with the other maps. Results show that the changes in amount of snow cover, as compared to to the 30 m resolution TM maps, are lowest using the TM 1km resolution maps, at 0–40%. The greatest change (>100%) is found in the New England study area, probably due to the presence of patchy snow cover. A scene with patchy snow cover is more difficult to map accurately than is a scene with a well-defined snowline such as is found on the North and South Dakota scene where the changes were 0–40%. There are also some important differences in the amount of snow mapped using the two different SSM/I algorithms because they utilize different channels.
There are several hemispheric-scale satellite-derived snow-cover maps available, but none has been fully validated. For the period 23 October–25 December 2000, we compare snow maps of North America derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and operational snow maps from the U.S. National Oceanic and Atmospheric Administration (NOAA) National Operational Hydrologic Remote Sensing Center (NOHRSC), both of which rely on satellite data from the visible and near-infrared parts of the spectrum; we also compare MODIS maps with Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I) passive-microwave snow maps for the same period. The maps derived from visible and near-infrared data are more accurate for mapping snow cover than are the passive-microwave-derived maps, but discrepancies exist as to the location and extent of the snow cover even between operational snow maps. The MODIS snow-cover maps show more snow in each of the 8 day periods than do the NOHRSC maps, in part because MODIS maps the effects of fleeting snowstorms due to its frequent coverage. The large (~30 km) footprint of the SSM/I pixel, and the difficulty in distinguishing wet and shallow snow from wet or snow-free ground, reveal differences up to 5.33 x 106 km2 in the amount of snow mapped using MODIS vs SSM/I data. Algorithms that utilize both visible and passive-microwave data, which would take advantage of the all-weather mapping capability of the passive-microwave data, will be refined following the launch of the Advanced Microwave Scanning Radiometer (AMSR) in the fall of 2001.
This study presents a new groove profile using the slant groove depth arrangements to enhance the performance of micro-HGJBs. The computational analysis was based on the steady-state three-dimensional conservation equations of mass and momentum in conjunction with the cavitation model to examine the complex lubricated flow field. The simulated results of load capacity and circumferential pressure distribution of lubricant film are in good agreement with the measurement data and the predictions cited in the literature. Numerical experiments were extended to determine the pressure distribution, load capacity, radial stiffness and friction torque by varying the slant ratio of groove depth, eccentricity ratio, rotational speed and attitude angle. The cavitation extent of lubricant film was also studied for different slant groove patterns.
A global, monthly snow depth data set has been generated from weather satellite (Nimbus 7) observations using passive microwave remote-sensing techniques. In this paper we analyzed five years of data, 1980–1984, to compute the snow-load excitation of the annual wobble of the Earth's rotation axis. A uniform sea-level decrease has been assumed in order to conserve water mass. The result shows dominant seasonal cycles. The prograde component of the annual excitation is Ψ+ = (5.0 milliarcsec, −110*) and the retrograde component Ψ− = (5.0 milliarcsec, −31*). These computed values are compared with previous groundwater estimates, as well as the inferred values from ILS and LAGEOS polar motion measurements. The importance of accurate data is stressed and future plans proposed.