Disappearing galaxies: the orientation dependence of JWST-bright, HST-dark, star-forming galaxy selection

Galaxies that are invisible in deep optical-NIR imaging but detected at longer wavelengths have been the focus of several recent observational studies, with speculation that they could constitute a substantial missing population and even dominate the cosmic star formation rate density at $z\gtrsim4$. The depths now achievable with JWST at the longest wavelengths probed by HST, coupled with the transformative resolution at longer wavelengths, are already enabling detailed, spatially-resolved characterisation of sources that were invisible to HST, often known as `HST-dark' galaxies. However, until now, there has been little theoretical work to compare against. We present the first simulation-based study of this population, using highly-resolved galaxies from the Feedback in Realistic Environments (FIRE) project, with multi-wavelength images along several lines of sight forward-modelled using radiative transfer. We naturally recover a population of modelled sources that meet commonly-used selection criteria ($H_{\rm{AB}}>27\,\rm{mag}$ and $H_{\rm{AB}}-\rm{F444W}>2.3$). These simulated HST-dark galaxies lie at high redshifts ($z=4-7$), have high levels of dust attenuation ($A_{V}=2-4$), and display compact recent star formation ($R_{1/2,\,\rm{4.4\,\mu\rm{m}}}\lesssim1\,\rm{kpc}$). Orientation is very important: for all but one of the 17 simulated galaxy snapshots with HST-dark sightlines, there exist other sightlines that do not meet the criteria. This result has important implications for comparisons between observations and models that do not resolve the detailed star-dust geometry, such as semi-analytic models or coarsely-resolved hydrodynamical simulations. Critically, we demonstrate that HST-dark sources are not an unexpected or exotic population, but a subset of high-redshift, highly-dust-attenuated sources viewed along certain lines of sight.Comment: 12 pages, 8 figures. Accepted for publication in Ap

Effects of Commercial Formaldehyde Inclusion and Lysine Level on Pig Performance of 35- to 50-lb Nursery Pigs

A total of 299 pigs (DNA 400 × 200; initial BW 33.6 lb) were used in a 14-d study to determine the effects of two separate commercial formaldehyde products (Termin-8; Anitox Corp, Lawrenceville, GA and SalCURB; Kemin Industries, Inc., Des Moines, IA) on nursery pig performance. Dietary treatments were arranged in a 3 × 2 factorial design with three formaldehyde inclusions: none vs. 6.5 lb/ton SalCURB vs. 6.0 lb/ton Termin-8 and 2 Lys levels: Standard (1.25% SID Lys) vs. Low (1.10% SID Lys). Formaldehyde treatments were established based on supplier recommendations and diets were treated with supplier-specific equipment. Pens of pigs were balanced by initial BW and randomly allotted to one of six treatments with five pigs per pen and 10 pens per treatment. Overall, there was a tendency (P \u3c 0.10) for a formaldehyde source × Lys level interaction to affect ADG and F/G, but not ADFI. Pigs fed diets with standard Lys levels, regardless of formaldehyde source, tended to have similar (P \u3e 0.10) ADG to one another, but greater (P \u3c 0.10) ADG than pigs fed low Lys levels treated with either formaldehyde source. Furthermore, pigs fed standard Lys levels treated with no formaldehyde or SalCURB tended to have improved (P \u3c 0.10) F/G compared to pigs fed standard Lys levels treated with Termin-8 or low Lys levels treated with no formaldehyde or SalCURB. Pigs fed diets with low Lys and treated with Termin-8 tended to have poorer (P \u3c 0.10) F/G than all other treatments. Regardless of source or Lys level, the inclusion of formaldehyde in nursery pig diets tended to reduce (P \u3c 0.10) ADG and resulted in poorer (P \u3c 0.05) F/G. Furthermore, the main effect of formaldehyde source affected (P \u3c 0.05) ADG, F/G, and tended to affect (P \u3c 0.10) ADFI, with pigs fed Termin-8 performing poorer than those fed SalCURB or no formaldehyde. As expected, Lys level affected (P \u3c 0.05) ADG and F/G, but did not alter ADFI (P \u3e 0.10). In summary, SalCURB inclusion did not alter nursery pig growth performance compared to the untreated basal diet, regardless of Lys level. However, the inclusion of Termin-8 tended to result in poorer F/G in standard Lys diets and poorer ADG and F/G in low Lys diets compared to an untreated control

Field measurements of trace gases and aerosols emitted by peat fires in Central Kalimantan, Indonesia, during the 2015 El Nino

Abstract. Peat fires in Southeast Asia have become a major annual source of trace gases and particles to the regional–global atmosphere. The assessment of their influence on atmospheric chemistry, climate, air quality, and health has been uncertain partly due to a lack of field measurements of the smoke characteristics. During the strong 2015 El Niño event we deployed a mobile smoke sampling team in the Indonesian province of Central Kalimantan on the island of Borneo and made the first, or rare, field measurements of trace gases, aerosol optical properties, and aerosol mass emissions for authentic peat fires burning at various depths in different peat types. This paper reports the trace gas and aerosol measurements obtained by Fourier transform infrared spectroscopy, whole air sampling, photoacoustic extinctiometers (405 and 870 nm), and a small subset of the data from analyses of particulate filters. The trace gas measurements provide emission factors (EFs; grams of a compound per kilogram biomass burned) for up to  ∼  90 gases, including CO2, CO, CH4, non-methane hydrocarbons up to C10, 15 oxygenated organic compounds, NH3, HCN, NOx, OCS, HCl, etc. The modified combustion efficiency (MCE) of the smoke sources ranged from 0.693 to 0.835 with an average of 0.772 ± 0.053 (n  =  35), indicating essentially pure smoldering combustion, and the emissions were not initially strongly lofted. The major trace gas emissions by mass (EF as g kg−1) were carbon dioxide (1564 ± 77), carbon monoxide (291 ± 49), methane (9.51 ± 4.74), hydrogen cyanide (5.75 ± 1.60), acetic acid (3.89 ± 1.65), ammonia (2.86 ± 1.00), methanol (2.14 ± 1.22), ethane (1.52 ± 0.66), dihydrogen (1.22 ± 1.01), propylene (1.07 ± 0.53), propane (0.989 ± 0.644), ethylene (0.961 ± 0.528), benzene (0.954 ± 0.394), formaldehyde (0.867 ± 0.479), hydroxyacetone (0.860 ± 0.433), furan (0.772 ± 0.035), acetaldehyde (0.697 ± 0.460), and acetone (0.691 ± 0.356). These field data support significant revision of the EFs for CO2 (−8 %), CH4 (−55 %), NH3 (−86 %), CO (+39 %), and other gases compared with widely used recommendations for tropical peat fires based on a lab study of a single sample published in 2003. BTEX compounds (benzene, toluene, ethylbenzene, xylenes) are important air toxics and aerosol precursors and were emitted in total at 1.5 ± 0.6 g kg−1. Formaldehyde is probably the air toxic gas most likely to cause local exposures that exceed recommended levels. The field results from Kalimantan were in reasonable agreement with recent lab measurements of smoldering Kalimantan peat for “overlap species,” lending importance to the lab finding that burning peat produces large emissions of acetamide, acrolein, methylglyoxal, etc., which were not measurable in the field with the deployed equipment and implying value in continued similar efforts. The aerosol optical data measured include EFs for the scattering and absorption coefficients (EF Bscat and EF Babs, m2 kg−1 fuel burned) and the single scattering albedo (SSA) at 870 and 405 nm, as well as the absorption Ångström exponents (AAE). By coupling the absorption and co-located trace gas and filter data we estimated black carbon (BC) EFs (g kg−1) and the mass absorption coefficient (MAC, m2 g−1) for the bulk organic carbon (OC) due to brown carbon (BrC). Consistent with the minimal flaming, the emissions of BC were negligible (0.0055 ± 0.0016 g kg−1). Aerosol absorption at 405 nm was  ∼  52 times larger than at 870 nm and BrC contributed  ∼  96 % of the absorption at 405 nm. Average AAE was 4.97 ± 0.65 (range, 4.29–6.23). The average SSA at 405 nm (0.974 ± 0.016) was marginally lower than the average SSA at 870 nm (0.998 ± 0.001). These data facilitate modeling climate-relevant aerosol optical properties across much of the UV/visible spectrum and the high AAE and lower SSA at 405 nm demonstrate the dominance of absorption by the organic aerosol. Comparing the Babs at 405 nm to the simultaneously measured OC mass on filters suggests a low MAC ( ∼  0.1) for the bulk OC, as expected for the low BC/OC ratio in the aerosol. The importance of pyrolysis (at lower MCE), as opposed to glowing (at higher MCE), in producing BrC is seen in the increase of AAE with lower MCE (r2 =  0.65)

Use of modified U1 snRNAs to inhibit HIV-1 replication

Control of RNA processing plays a central role in regulating the replication of HIV-1, in particular the 3′ polyadenylation of viral RNA. Based on the demonstration that polyadenylation of mRNAs can be disrupted by the targeted binding of modified U1 snRNA, we examined whether binding of U1 snRNAs to conserved 10 nt regions within the terminal exon of HIV-1 was able to inhibit viral structural protein expression. In this report, we demonstrate that U1 snRNAs complementary to 5 of the 15 regions targeted result in significant suppression of HIV-1 protein expression and viral replication coincident with loss of viral RNA. Suppression of viral gene expression is dependent upon appropriate assembly of a U1 snRNP particle as mutations of U1 snRNA that affect binding of U1 70K or Sm proteins significantly reduced efficacy. However, constructs lacking U1A binding sites retained significant anti-viral activity. This finding suggests a role for these mutants in situations where the wild-type constructs cause toxic effects. The conserved nature of the sequences targeted and the high efficacy of the constructs suggests that this strategy has significant potential as an HIV therapeutic

Understanding the scale and nature of outcome change in area-regeneration programmes: evidence from the New Deal for Communities Programme in England

The New Deal for Communities (NDC) Programme is one of the most intensive area-based initiatives (ABIs) launched in England. Between 1998 and 2010, 39 NDC Partnerships were charged with improving conditions in relation to six outcomes within deprived neighbourhoods, each accommodating around 9,800 people. Data point to only modest change, much of which reflected improving attitudes towards the area and the environment. There are problems in identifying positive people-based outcomes because relatively few individuals benefit from relevant initiatives. Few positive benefits leak out of NDC areas. Transformational change was always unlikely bearing in mind the limited nature of additional resources, and because only a minority of individuals directly engage with NDC projects. This evidence supports perspectives of ABIs rooted in 'local-managerialism'

Beware the recent past: a bias in spectral energy distribution modelling due to bursty star formation

We investigate how the recovery of galaxy star formation rates (SFRs) using energy-balance spectral energy distribution (SED) fitting codes depends on their recent star formation histories (SFHs). We use the Magphys and Prospector codes to fit 6,706 synthetic spectral energy distributions (SEDs) of simulated massive galaxies at $1 < z < 8$ from the Feedback in Realistic Environments (FIRE) project. We identify a previously unknown systematic error in the Magphys results due to bursty star formation: the SFR estimates of individual galaxies can differ from the true values by as much as 1 dex, at large statistical significance ($>5\sigma$), depending on the details of their recent SFH. The SFRs inferred using Prospector do not exhibit this trend, likely because unlike Magphys, Prospector uses non-parametric SFHs. We urge caution when using Magphys, or other codes assuming parametric SFHs, to study galaxies where the average SFR may have changed significantly over the last $\sim$100 Myr, such as those which have recently quenched their star formation or those experiencing an ongoing burst. This concern is especially relevant, for example, when fitting JWST observations of very high-redshift galaxies.Comment: 5 pages, 3 figures, submitted to MNRAS Letter

Macroscopically distinct quantum superposition states as a bosonic code for amplitude damping

We show how macroscopically distinct quantum superposition states (Schroedinger cat states) may be used as logical qubit encodings for the correction of spontaneous emission errors. Spontaneous emission causes a bit flip error which is easily corrected by a standard error correction circuit. The method works arbitrarily well as the distance between the amplitudes of the superposed coherent states increases.Comment: 4 pages, 2 postscript figures, LaTeX2e, RevTeX, minor changes, 1 reference adde

Evaluating Chemical Mitigation of Porcine Epidemic Diarrhea Virus (PEDV) in Swine Feed and Ingredients

Porcine Epidemic Diarrhea Virus (PEDV) is primarily transmitted by fecal-oral contamination. Research has confirmed swine feed or ingredients as potential vectors of transmission, so strategies are needed to mitigate PEDV in feed. The objective of this experiment was to evaluate the effectiveness of various chemical additives to prevent or mitigate post-processing PEDV contamination in swine feed and ingredients. Treatments were arranged in a 7 × 4 factorial with seven chemical treatments and four feed matrices. The chemical treatments included: negative control with no chemical addition, 0.3% commercial formaldehyde product, 1% sodium bisulfate, 1% sodium chlorate, 3% custom organic acid blend (OA), 2% custom essential oil blend (EO), and 2% custom medium chain fatty acid blend (MCFA). The four matrices included a complete swine diet, blood meal, meat and bone meal, and spray-dried animal plasma. Matrices were first chemically treated, then inoculated with PEDV, stored at room temperature, and analyzed by RT-PCR on d 0, 1, 3, 7, 14, 21, and 42 post inoculation. Formaldehyde, MCFA, EO, and OA addition each decreased RNA concentration of PEDV compared to the control (P \u3c 0.05), with formaldehyde being the most effective on d 0. Feed matrix appears important in PEDV retention, as RNA concentrations were lower in the swine diet and blood meal than meat and bone meal or spray-dried animal plasma on d 0 (P \u3c 0.05). Additionally, PEDV stability over time was influenced by matrix as RNA concentrations were greater by d 42 for spray-dried animal plasma and meat and bone meal than the complete swine diet and blood meal. In summary, time, formaldehyde, MCFA, EO, and OA all enhance the RNA degradation of PEDV in swine feed and ingredients as measured by RT-PCR, but their effectiveness varies within matrix. Notably, the MCFA was equally as successful at mitigating PEDV as a commercially-available formaldehyde product