Despite its excellent public healthcare system and efficient public administration, Singapore has been severely affected by the COVID-19 pandemic. While fatalities in the city-state remain low and ...contact tracing efforts have been largely successful, it has nonetheless experienced high rates of infection and the emergence of large infection clusters in its foreign worker dormitories. This paper analyses this dual-track policy outcome - low fatalities but high infection rates - from a policy capacity perspective. Specifically, the policy capacities that had contributed to Singapore's low fatality rates and effective contact tracing are identified while the capacity deficiencies that may have caused its high rates of infection are discussed. In doing so, I argue that the presence of fiscal, operational and political capacities that were built up after the SARS crisis had contributed to Singapore's low fatality rate and contact tracing capabilities while deficiencies in analytical capacities may explain its high infection rate.
Context. Feedback from active galactic nuclei (AGN) is thought to play an important role in quenching star formation in galaxies. However, the efficiency with which AGN dissipate their radiative ...energy into the ambient medium remains strongly debated. Aims. Enormous observational efforts have been made to constrain the energetics of AGN feedback by mapping the kinematics of the ionized gas on kpc scale. We study how the observed kinematics and inferred energetics are affected by beam smearing of a bright unresolved narrow-line region (NLR) due to seeing. Methods. We re-analyse optical integral-field spectroscopy of a sample of twelve luminous unobscured quasi-stellar objects (QSOs) (0.4 <z< 0.7) previously presented in the literature. The point-spread function (PSF) for the observations is directly obtained from the light distribution of the broad Hbeta line component. Therefore, we are able to compare the ionized gas kinematics and derived energetics of the total, truly spatially extended, and unresolved Oiii emission. Results. We find that the spatially resolved Oiii line width on kpc scales is significantly narrower than the one before PSF deblending. The extended NLRs (ENLRs) appear intrinsically offset from the QSO position or more elongated which can be interpreted in favour of a conical outflow on large scales while a spherical geometry cannot be ruled out for the unresolved NLR. We find that the kinetic power at 5 kpc distance based on a spherical model is reduced by two orders of magnitude for a conical outflow and one order of magnitude for the unresolved NLR after PSF deblending. This reduced kinetic power corresponds to only 0.01-0.1 per cent of the bolometric AGN luminosity. This is smaller than the 5-10% feedback efficiency required by some cosmological simulations to reproduce the massive galaxy population. The injected momentum fluxes are close or below the simple radiation-pressure limit L sub(bol)/c for the conical outflow model for the NLR and ENLR when beam smearing is considered. Conclusions. Integral-field spectroscopy is a powerful tool to investigate the energetics of AGN outflows, but the impact of beam smearing has to be taken into account in the high contrast regime of QSOs. For the majority of observations in the literature, this has not been addressed carefully so that the incidence and energetics of presumed kpc-scale AGN-driven outflows still remain an unsolved issue, from an observational perspective.
We use the high-resolution simulation MassiveBlackII to examine scaling relations between black hole (BH) mass and host galaxy properties (σ, total M
* and L
V
), finding good agreement with recent ...observational data, especially at the high-mass end. We find Gaussian intrinsic scatter (∼half the observed scatter) about all three relations, except among the most massive objects. Below z ∼ 2 the slope of the relations remain roughly z-independent, and only steepen by 50 per cent by z ∼ 4. The normalization of the σ, L
V
relations evolve by 0.3, 0.43 dex, while the M
* correlation does not evolve out to at least z ∼ 2. Testing for selection biases, we find M
BH- or M
*-selected samples have steeper slopes than random samples, suggesting a constant-mass selection function can exhibit faster evolution than a random sample. We find a potential bias among high-L
BH subsamples due to their more massive hosts, but that bright (active) active galactic nuclei exhibit no intrinsic bias relative to fainter (inactive) BHs in equivalent-mass hosts. Finally, we show that BHs below the local relation tend to grow faster than their host (72 per cent of BHs >0.3 dex below the mean relation have an M
BH–M
* trajectory steeper than the local relation), while those above have shallower trajectories (only 14 per cent are steeper than local). Thus BHs tend to grow faster than their hosts until surpassing the local relation, when their growth is suppressed, bringing them back towards the mean relation.
An inventory of air pollutant emissions in Asia in the year 2000 is developed to support atmospheric modeling and analysis of observations taken during the TRACE‐P experiment funded by the National ...Aeronautics and Space Administration (NASA) and the ACE‐Asia experiment funded by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA). Emissions are estimated for all major anthropogenic sources, including biomass burning, in 64 regions of Asia. We estimate total Asian emissions as follows: 34.3 Tg SO2, 26.8 Tg NOx, 9870 Tg CO2, 279 Tg CO, 107 Tg CH4, 52.2 Tg NMVOC, 2.54 Tg black carbon (BC), 10.4 Tg organic carbon (OC), and 27.5 Tg NH3. In addition, NMVOC are speciated into 19 subcategories according to functional groups and reactivity. Thus we are able to identify the major source regions and types for many of the significant gaseous and particle emissions that influence pollutant concentrations in the vicinity of the TRACE‐P and ACE‐Asia field measurements. Emissions in China dominate the signature of pollutant concentrations in this region, so special emphasis has been placed on the development of emission estimates for China. China's emissions are determined to be as follows: 20.4 Tg SO2, 11.4 Tg NOx, 3820 Tg CO2, 116 Tg CO, 38.4 Tg CH4, 17.4 Tg NMVOC, 1.05 Tg BC, 3.4 Tg OC, and 13.6 Tg NH3. Emissions are gridded at a variety of spatial resolutions from 1° × 1° to 30 s × 30 s, using the exact locations of large point sources and surrogate GIS distributions of urban and rural population, road networks, landcover, ship lanes, etc. The gridded emission estimates have been used as inputs to atmospheric simulation models and have proven to be generally robust in comparison with field observations, though there is reason to think that emissions of CO and possibly BC may be underestimated. Monthly emission estimates for China are developed for each species to aid TRACE‐P and ACE‐Asia data interpretation. During the observation period of March/April, emissions are roughly at their average values (one twelfth of annual). Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of ±16% for SO2 to a high of ±450% for OC.
To understand the anti‐inflammaging effect of lactic acid bacteria, we selected NF‐κB activation‐inhibitory Lactobacillus pentosus var. plantarum C29 and investigated its memory‐enhancing and ...anti‐inflammatory effects in aged Fischer 344 rats. C29 (2 × 10⁹ CFU rat⁻¹), which was orally administered once a day (6 days per week) for 8 weeks, significantly restored age‐reduced spontaneous alternation to 95·2% of that seen in young rats (P < 0·05). C29 treatment also shortened the escape latency on the 4th day to 53·8% of that seen in young rats (P < 0·05). Twenty hours after the last training session, C29 significantly increased the swimming time within the platform quadrant, which was shortened in the aged control rats. Oral administration of C29 restored age‐reduced doublecortin (DCX) and brain‐derived neurotrophic factor (BDNF) expression and cAMP response element binding protein (CREB) activation in aged rats. Treatment of aged rats with C29 suppressed the expression of p16, cyclooxygenase‐2, and inducible nitric oxide synthase, as well as the activation of Akt, mTOR, and NF‐κB in the hippocampus. These findings suggest that C29 ameliorates ageing‐dependent memory impairment by inhibiting NF‐κB signalling pathway, inducing DCX and BDNF expression and activating CREB. SIGNIFICANCE AND IMPACT OF THE STUDY: The anti‐inflammatory Lactobacillus pentosus var. plantarum C29 had the memory‐enhancing effect in aged Fischer 344 rats by restoring doublecortin and brain‐derived neurotrophic factor expression and suppressing p16 expression and NF‐κB activation in the brain. Therefore, C29 may be useful in ameliorating age‐related degenerative dementia.
Estimates of biomass burning in Asia are developed to facilitate the modeling of Asian and global air quality. A survey of national, regional, and international publications on biomass burning is ...conducted to yield consensus estimates of “typical” (i.e., non‐year‐specific) estimates of open burning (excluding biofuels). We conclude that 730 Tg of biomass are burned in a typical year from both anthropogenic and natural causes. Forest burning comprises 45% of the total, the burning of crop residues in the field comprises 34%, and 20% comes from the burning of grassland and savanna. China contributes 25% of the total, India 18%, Indonesia 13%, and Myanmar 8%. Regionally, forest burning in Southeast Asia dominates. National, annual totals are converted to daily and monthly estimates at 1° × 1° spatial resolution using distributions based on AVHRR fire counts for 1999–2000. Several adjustment schemes are applied to correct for the deficiencies of AVHRR data, including the use of moving averages, normalization, TOMS Aerosol Index, and masks for dust, clouds, landcover, and other fire sources. Good agreement between the national estimates of biomass burning and adjusted fire counts is obtained (R2 = 0.71–0.78). Biomass burning amounts are converted to atmospheric emissions, yielding the following estimates: 0.37 Tg of SO2, 2.8 Tg of NOx, 1100 Tg of CO2, 67 Tg of CO, 3.1 Tg of CH4, 12 Tg of NMVOC, 0.45 Tg of BC, 3.3 Tg of OC, and 0.92 Tg of NH3. Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of ±65% for CO2 emissions in Japan to a high of ±700% for BC emissions in India.
Recent high precision meteoritic data improve constraints on the formation timescale and bulk composition of the terrestrial planets. High resolution N-body simulations allow direct comparison of ...embryo growth timescale and accretion zones to these constraints. In this paper, we present results of high resolution simulations for embryo formation from a disc of up to 41,000 fully-self gravitating planetesimals with the GPU-based N-body code GENGA. Our results indicate that the growth of embryos are highly dependent on the initial conditions. More massive initial planetesimals, a shorter gas disc decay timescale and initially eccentric Jupiter and Saturn (EJS) all lead to faster growth of embryos. Asteroid belt material can thereby be implanted into the terrestrial planet region via sweeping secular resonances. This could possibly explain the rapid growth of Mars within 10 Myr inferred from its Hf-W chronology. The sweeping secular resonance almost completely clears the asteroid belt and deposits this material in the Mercury-Venus region, altering the composition of embryos there. This could result in embryos in the Mercury-Venus region accreting an unexpectedly high mass fraction from beyond 2 AU. Changing the initial orbits of Jupiter and Saturn to more circular (CJS) or assuming embryos formed in a gas free environment removes the sweeping secular resonance effect and thus greatly decreases material accreted from beyond 2 AU for Mercury-Venus region embryos. We therefore propose that rock samples from Mercury and Venus could aid greatly in deducing the condition and lifetime of the initial protoplanetary gas disc during planetesimal and embryo formation, as well as the initial architecture of the giant planets.
•Embryo growth timescale is affected by initial planetesimal size•Criteria for fast growth of Mars: EJS, large planetesimals, short-lived gas disc•Sweeping secular resonance alters the composition of embryos•Samples from Mercury and Venus can constrain initial gas giant orbits
Active neurons exert a mitogenic effect on normal neural precursor and oligodendroglial precursor cells, the putative cellular origins of high-grade glioma (HGG). By using optogenetic control of ...cortical neuronal activity in a patient-derived pediatric glioblastoma xenograft model, we demonstrate that active neurons similarly promote HGG proliferation and growth in vivo. Conditioned medium from optogenetically stimulated cortical slices promoted proliferation of pediatric and adult patient-derived HGG cultures, indicating secretion of activity-regulated mitogen(s). The synaptic protein neuroligin-3 (NLGN3) was identified as the leading candidate mitogen, and soluble NLGN3 was sufficient and necessary to promote robust HGG cell proliferation. NLGN3 induced PI3K-mTOR pathway activity and feedforward expression of NLGN3 in glioma cells. NLGN3 expression levels in human HGG negatively correlated with patient overall survival. These findings indicate the important role of active neurons in the brain tumor microenvironment and identify secreted NLGN3 as an unexpected mechanism promoting neuronal activity-regulated cancer growth.
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•Neuronal activity promotes high-grade glioma (HGG) proliferation and growth•Neuroligin-3 is an activity-regulated secreted glioma mitogen•Neuroligin-3 induces PI3K-mTOR signaling in HGG cells•Neuroligin-3 expression is inversely correlated with survival in human HGG
Neuronal activity promotes the growth of malignant glioma through activity-regulated secretion of the synaptic protein neuroligin-3, which acts as a mitogen, recruiting the PI3K-mTOR pathway to induce glioma cell proliferation.
Supernova (SN) 2009ig was discovered 17 hr after explosion by the Lick Observatory Supernova Search, promptly classified as a normal Type Ia SN (SN Ia), peaked at V = 13.5 mag, and was equatorial, ...making it one of the foremost SNe for intensive study in the last decade. Here, we present ultraviolet (UV) and optical observations of SN 2009ig, starting about 1 day after explosion until around maximum brightness. Our data include excellent UV and optical light curves, 25 premaximum optical spectra, and 8 UV spectra, including the earliest UV spectrum ever obtained of an SN Ia. SN 2009ig is a relatively normal SN Ia, but does display high-velocity ejecta--the ejecta velocity measured in our earliest spectra (v --2,000 km s--1 for Si II Delta *l6355) is the highest yet measured in an SN Ia. The spectral evolution is very dramatic at times earlier than 12 days before maximum brightness, but slows after that time. The early-time data provide a precise measurement of 17.13 ? 0.07 days for the SN rise time. The optical color curves and early-time spectra are significantly different from template light curves and spectra used for light-curve fitting and K-corrections, indicating that the template light curves and spectra do not properly represent all SNe Ia at very early times. In the age of wide-angle sky surveys, SNe like SN 2009ig that are nearby, bright, well positioned, and promptly discovered will still be rare. As shown with SN 2009ig, detailed studies of single events can provide significantly more information for testing systematic uncertainties related to SN Ia distance estimates and constraining progenitor and explosion models than large samples of more distant SNe.
This research examines how counterfactual potency (CP), the multiplicative effect of the likelihoods of the “if” and “then” clauses of counterfactuals, determines the effects of counterfactuals on ...behavioral intentions. In Study 1, we found that participants who read highly (vs. minimally) mutable vignettes perceived the counterfactuals as more likely and endorsed relevant intentions more. However, CP did not mediate the effect of mutability on intentions. In Studies 2 and 3, we found that CP directly affected intentions and also mediated the effects of mutability on intentions when mutability was specifically manipulated via controllability (Study 2) or norm violation (Study 3). Finally, Study 4 used archival reaction time data to show that more concrete counterfactuals were perceived as more likely and subsequently facilitated intentions. Taken together, the current research provides evidence that more likely counterfactuals facilitate behavioral intentions.
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