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Harmonic measurements of the longitudinal and transverse voltages in Bi-Sb/Co bilayers are presented. A large second harmonic voltage signal due to the ordinary Nernst effect is observed. In experiments where a magnetic field is rotated in the film plane, the ordinary Nernst effect shows the same angular dependence in the transverse voltage as the dampinglike spin-orbit torque and in the longitudinal voltage as the unidirectional spin-Hall magnetoresistance, respectively. Therefore, the ordinary Nernst effect can be a spurious signal in spin-orbit torque measurements, leading to an overestimation of the spin-Hall angle and spin-Hall conductivity in topological insulators or semimetals.

The Carnegie Supernova Project-II (CSP-II) was an NSF-funded, four-year program to obtain optical and near-infrared observations of a “Cosmology” sample of ∼100 TypeIa supernovae located in the smooth Hubble flow (0.03

We present detailed ultraviolet, optical, and near-infrared light curves of the Type Ia supernova (SN) 2012fr, which exploded in the Fornax cluster member NGC 1365. These precise high-cadence light curves provide a dense coverage of the flux evolution from -12 to +140 days with respect to the epoch of B-band maximum (). Supplementary imaging at the earliest epochs reveals an initial slow and nearly linear rise in luminosity with a duration of ∼2.5 days, followed by a faster rising phase that is well reproduced by an explosion model with a moderate amount of 56Ni mixing in the ejecta. From our analysis of the light curves, we conclude that: (i) the explosion occurred 1800) luminosity was 16.5 ±0.6 days, (iii) the supernova suffered little or no host-galaxy dust reddening, (iv) the peak luminosity in both the optical and near-infrared was consistent with the bright end of normal Type Ia diversity, and (v) 0.60 ±0.15 M o of 56Ni was synthesized in the explosion. Despite its normal luminosity, SN 2012fr displayed unusually prevalent high-velocity Ca ii and Si ii absorption features, and a nearly constant photospheric velocity of the Si ii λ6355 line at ∼12,000 that began ∼5 days before . We also highlight some of the other peculiarities in the early phase photometry and the spectral evolution. SN 2012fr also adds to a growing number of Type Ia supernovae that are hosted by galaxies with direct Cepheid distance measurements.

The La Silla/QUEST Variability Survey (LSQ) and the Carnegie Supernova Project (CSP II) are collaborating to discover and obtain photometric light curves for a large sample of low-redshift (z < 0.1) Type Ia supernovae (SNe Ia). The supernovae are discovered in the LSQ survey using the 1 m ESO Schmidt telescope at the La Silla Observatory with the 10 square degree QUEST camera. The follow-up photometric observations are carried out using the 1 m Swope telescope and the 2.5 m du Pont telescopes at the Las Campanas Observatory. This paper describes the survey, discusses the methods of analyzing the data, and presents the light curves for the first 31 SNe Ia obtained in the survey. The SALT 2.4 supernova light-curve fitter was used to analyze the photometric data, and the Hubble diagram for this first sample is presented. The measurement errors for these supernovae averaged 4%, and their intrinsic spread was 14%.

We present optical observations of the peculiar stripped-envelope supernovae (SNe) LSQ12btw and LSQ13ccw discovered by the La Silla-QUEST survey. LSQ12btw reaches an absolute peak magnitude of Mg = -19.3 ± 0.2, and shows an asymmetric light curve. Stringent pre-discovery limits constrain its rise time to maximum light to less than 4 d, with a slower post-peak luminosity decline, similar to that experienced by the prototypical SN Ibn 2006jc. LSQ13ccw is somewhat different: while it also exhibits a very fast rise to maximum, it reaches a fainter absolute peak magnitude (Mg =-18.4 ± 0.2), and experiences an extremely rapid post-peak decline similar to that observed in the peculiar SN Ib 2002bj. A stringent pre-discovery limit and an early marginal detection of LSQ13ccw allow us to determine the explosion time with an uncertainty of ±1 d. The spectra of LSQ12btw show the typical narrow He I emission lines characterizing Type Ibn SNe, suggesting that the SN ejecta are interacting with He-rich circumstellar material. The He I lines in the spectra of LSQ13ccw exhibit weak narrow emissions superposed on broad components. An unresolved Ha line is also detected, suggesting a tentative Type Ibn/IIn classification. As for other SNe Ibn, we argue that LSQ12btw and LSQ13ccw likely result from the explosions of Wolf-Rayet stars that experienced instability phases prior to core collapse. We inspect the host galaxies of SNe Ibn, and we show that all of them but one are hosted in spiral galaxies, likely in environments spanning a wide metallicity range.

We present an analysis of the early, rising light curves of 18 Type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory and the La Silla-QUEST variability survey. We fit these early data flux using a simple power law (f(t) = α × tn) to determine the time of first light (t0), and hence the rise time (trise) from first light to peak luminosity, and the exponent of the power-law rise (n). We find a mean uncorrected rise time of 18.98 ± 0.54 d, with individual supernova (SN) rise times ranging from 15.98 to 24.7 d. The exponent n shows significant departures from the simple 'fireball model' of n = 2 (or f(t)αt2) usually assumed in the literature.With a mean value of n = 2.44 ± 0.13, our data also show significant diversity from event to event. This deviation has implications for the distribution of 56Ni throughout the SN ejecta, with a higher index suggesting a lesser degree of 56Ni mixing. The range of n found also confirms that the 56Ni distribution is not standard throughout the population of SNe Ia, in agreement with earlier work measuring such abundances through spectral modelling.We also show that the duration of the very early light curve, before the luminosity has reached half of its maximal value, does not correlate with the light-curve shape or stretch used to standardize SNe Ia in cosmological applications. This has implications for the cosmological fitting of SN Ia light curves.

We present optical spectra and light curves for three hydrogen-poor superluminous supernovae followed by the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). Time series spectroscopy from a fewdays aftermaximum light to 100 d later shows them to be fairly typical of this class, with spectra dominated by Ca II, MgII, FeII, and Si II, which evolve slowly over most of the post-peak photospheric phase. We determine bolometric light curves and apply simple fitting tools, based on the diffusion of energy input by magnetar spin-down, 56Ni decay, and collision of the ejecta with an opaque circumstellar shell. We investigate how the heterogeneous light curves of our sample (combined with others from the literature) can help to constrain the possible mechanisms behind these events. We have followed these events to beyond 100-200 d after peak, to disentangle host galaxy light from fading supernova flux and to differentiate between the models, which predict diverse behaviour at this phase. Models powered by radioactivity require unrealistic parameters to reproduce the observed light curves, as found by previous studies. Both magnetar heating and circumstellar interaction still appear to be viable candidates. A large diversity is emerging in observed tail-phase luminosities, with magnetar models failing in some cases to predict the rapid drop in flux. This would suggest either that magnetars are not responsible, or that the X-ray flux from the magnetar wind is not fully trapped. The light curve of one object shows a distinct rebrightening at around 100 d after maximum light. We argue that this could result either from multiple shells of circumstellar material, or from a magnetar ionization front breaking out of the ejecta.

We present photospheric-phase observations of LSQ12gdj, a slowly declining, UV-bright Type Ia supernova. Classified well before maximum light, LSQ12gdj has extinction-corrected absolute magnitude MB = -19.8, and pre-maximum spectroscopic evolution similar to SN 1991T and the super-Chandrasekhar-mass SN 2007if. We use ultraviolet photometry from Swift, ground-based optical photometry, and corrections from a near-infrared photometric template to construct the bolometric (1600-23 800 Å) light curve out to 45 d past B-band maximum light. We estimate that LSQ12gdj produced 0.96 ± 0.07 M· of 56Ni, with an ejected mass near or slightly above the Chandrasekhar mass. As much as 27 per cent of the flux at the earliest observed phases, and 17 per cent at maximum light, is emitted bluewards of 3300 Å. The absence of excess luminosity at late times, the cutoff of the spectral energy distribution bluewards of 3000 Å and the absence of narrow line emission and strong Na I D absorption all argue against a significant contribution from ongoing shock interaction. However, ~10 per cent of LSQ12gdj's luminosity near maximum light could be produced by the release of trapped radiation, including kinetic energy thermalized during a brief interaction with a compact, hydrogen-poor envelope (radius

We present optical photometry and spectroscopy of the broad-lined Type Ic supernova (SN Ic-BL) PTF10qts, which was discovered as part of the Palomar Transient Factory. The SN was located in a dwarf galaxy of magnitude r = 21.1 at a redshift z = 0.0907. We find that the R-band light curve is a poor proxy for bolometric data and use photometric and spectroscopic data to construct and constrain the bolometric light curve. The derived bolometric magnitude at maximum light is Mbol =-18.51 ± 0.2 mag, comparable to that of SN 1998bw (Mbol = -18.7 mag) which was associated with a gamma-ray burst (GRB). PTF10qts is one of the most luminous SNe Ic-BL observed without an accompanying GRB. We estimate the physical parameters of the explosion using data from our programme of follow-up observations, finding that it produced a larger mass of radioactive nickel compared to other SNe Ic-BL with similar inferred ejecta masses and kinetic energies. The progenitor of the event was likely an ~20 M⊙ star. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Hubble Space Telescope spectroscopic observations of the nearby Type Ia supernova (SN Ia) SN 2011fe, taken on 10 epochs from -13.1 to +40.8 d relative to B-band maximum light, and spanning the far-ultraviolet (UV) to the near-infrared (IR) are presented. This spectroscopic coverage makes SN 2011fe the best-studied local SN Ia to date. SN 2011fe is a typical moderately luminous SN Ia with no evidence for dust extinction. Its near-UV spectral properties are representative of a larger sample of local events (Maguire et al.). The near-UV to optical spectra of SN 2011fe are modelled with a Monte Carlo radiative transfer code using the technique of 'abundance tomography', constraining the density structure and the abundance stratification in the SN ejecta. SN 2011fe was a relatively weak explosion, with moderate Fe-group yields. The density structures of the classical model W7 and of a delayed detonation model were tested. Both have shortcomings. An ad hoc density distribution was developed which yields improved fits and is characterized by a high-velocity tail, which is absent in W7. However, this tail contains less mass than delayed detonation models. This improved model has a lower energy than one-dimensional explosion models matching typical SNe Ia (e.g. W7, WDD1; Iwamoto et al.). The derived Fe abundance in the outermost layer is consistent with the metallicity at the SN explosion site in M101 (̃0.5 z⊙). The spectroscopic rise-time (̃19 d) is significantly longer than that measured from the early optical light curve, implying a 'dark phase' of ̃1 d. A longer rise-time has significant implications when deducing the properties of the white dwarf and binary system from the early photometric behaviour. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

We present spectroscopic observations of the host galaxies of 82 low-redshift Type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory.We determine star formation rates, gas-phase/stellarmetallicities, and stellarmasses and ages of these objects. As expected, strong correlations between the SN Ia light-curve width (stretch) and the host age/mass/metallicity are found: fainter, faster declining events tend to be hosted by older/massive/metal-rich galaxies. There is some evidence that redder SNe Ia explode in higher metallicity galaxies, but we found no relation between the SN colour and host galaxy extinction based on the Balmer decrement, suggesting that the colour variation of these SNe does not primarily arise from this source. SNe Ia in higher mass/metallicity galaxies also appear brighter after stretch/colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also compared the host stellar mass distribution to that in galaxy-targeted SN surveys and the high-redshift untargeted Supernova Legacy Survey (SNLS). SNLS has many more low-mass galaxies, while the targeted searches have fewer. This can be explained by an evolution in the galaxy stellar mass function, coupled with an SN delay-time distribution proportional to t-1. Finally, we found no significant difference in the mass-metallicity relation of our SN Ia hosts compared to field galaxies, suggesting any metallicity effect on the SN Ia rate is small. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Hubble Space Telescope spectroscopic observations of the nearby Type Ia supernova (SN Ia) SN 2011fe, taken on 10 epochs from -13.1 to +40.8 d relative to B-band maximum light, and spanning the far-ultraviolet (UV) to the near-infrared (IR) are presented. This spectroscopic coverage makes SN 2011fe the best-studied local SN Ia to date. SN 2011fe is a typical moderately luminous SN Ia with no evidence for dust extinction. Its near-UV spectral properties are representative of a larger sample of local events (Maguire et al.). The near-UV to optical spectra of SN 2011fe are modelled with a Monte Carlo radiative transfer code using the technique of 'abundance tomography', constraining the density structure and the abundance stratification in the SN ejecta. SN 2011fe was a relatively weak explosion, with moderate Fe-group yields. The density structures of the classical model W7 and of a delayed detonation model were tested. Both have shortcomings. An ad hoc density distribution was developed which yields improved fits and is characterized by a high-velocity tail, which is absent in W7. However, this tail contains less mass than delayed detonation models. This improved model has a lower energy than one-dimensional explosion models matching typical SNe Ia (e.g. W7, WDD1; Iwamoto et al.). The derived Fe abundance in the outermost layer is consistent with the metallicity at the SN explosion site in M101 (̃0.5 z⊙). The spectroscopic rise-time (̃19 d) is significantly longer than that measured from the early optical light curve, implying a 'dark phase' of ̃1 d. A longer rise-time has significant implications when deducing the properties of the white dwarf and binary system from the early photometric behaviour. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

A key tracer of the elusive progenitor systems of Type Ia supernovae (SNe Ia) is the detection of narrow blueshifted time-varying Na I D absorption lines, interpreted as evidence of circumstellar material surrounding the progenitor system. The origin of this material is controversial, but the simplest explanation is that it results from previous mass-loss in a system containing a white dwarf and a non-degenerate companion star. We present new singleepoch intermediate-resolution spectra of 17 low-redshift SNe Ia taken with XShooter on the European Southern Observatory Very Large Telescope. Combining this sample with events from the literature, we confirm an excess (~20 per cent) of SNe Ia displaying blueshifted narrow Na I D absorption features compared to redshifted Na I D features. The host galaxies of SNe Ia displaying blueshifted absorption profiles are skewed towards later-type galaxies, compared to SNe Ia that show no Na I D absorption and SNe Ia displaying blueshifted narrow Na I D absorption features have broader light curves. The strength of the Na I D absorption is stronger in SNe Ia displaying blueshifted Na I D absorption features than those without blueshifted features, and the strength of the blueshifted Na I D is correlated with the B - V colour of the SN at maximum light. This strongly suggests the absorbing material is local to the SN. In the context of the progenitor systems of SNe Ia, we discuss the significance of these findings and other recent observational evidence on the nature of SN Ia progenitors. We present a summary that suggests that there are at least two distinct populations of normal, cosmologically useful SNe Ia. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

The intermediate Palomar Transient Factory reports our discovery of a young supernova, iPTF13bvn, in the nearby galaxy, NGC 5806 (22.5 Mpc). Our spectral sequence in the optical and infrared suggests a Type Ib classification. We identify a blue progenitor candidate in deep pre-explosion imaging within a 2σ error circle of 80 mas (8.7 pc). The candidate has an MB luminosity of -5.52 ± 0.39 mag and a B-I color of 0.25 ± 0.25 mag. If confirmed by future observations, this would be the first direct detection for a progenitor of a Type Ib. Fitting a power law to the early light curve, we find an extrapolated explosion date around 0.6 days before our first detection. We see no evidence of shock cooling. The pre-explosion detection limits constrain the radius of the progenitor to be smaller than a few solar radii. iPTF13bvn is also detected in centimeter and millimeter wavelengths. Fitting a synchrotron self-absorption model to our radio data, we find a mass-loading parameter of 1.3×1012 g cm-1. Assuming a wind velocity of 103 km s-1, we derive a progenitor mass-loss rate of 3 × 10-5 M ⊙ yr-1. Our observations, taken as a whole, are consistent with a Wolf-Rayet progenitor of the supernova iPTF13bvn. © 2013. The American Astronomical Society. All rights reserved..

We present the discovery and extensive early-time observations of the Type Ic supernova (SN) PTF12gzk. Our light curves show a rise of 0.8mag within 2.5hr. Power-law fits (f(t) (t - t 0)n) to these data constrain the explosion date to within one day. We cannot rule out a quadratic fireball model, but higher values of n are possible as well for larger areas in the fit parameter space. Our bolometric light curve and a dense spectral sequence are used to estimate the physical parameters of the exploding star and of the explosion. We show that the photometric evolution of PTF12gzk is slower than that of most SNe Ic. The high ejecta expansion velocities we measure (∼30, 000kms-1 derived from line minima fourdays after explosion) are similar to the observed velocities of broad-lined SNe Ic associated with gamma-ray bursts (GRBs) rather than to normal SN Ic velocities. Yet, this SN does not show the persistent broad lines that are typical of broad-lined SNe Ic. The host-galaxy characteristics are also consistent with GRB-SN hosts, and not with normal SN Ic hosts. By comparison with the spectroscopically similar SN 2004aw, we suggest that the observed properties of PTF12gzk indicate an initial progenitor mass of 25-35M ⊙ and a large ((5-10) × 10 51erg) kinetic energy, the later being close to the regime of GRB-SN properties. © 2012. The American Astronomical Society. All rights reserved.

The nearby Type Ia supernova (SNIa) SN2011fe in M101 (cz = 241kms -1) provides a unique opportunity to study the early evolution of a "normal" SNIa, its compositional structure, and its elusive progenitor system. We present 18 high signal-to-noise spectra of SN2011fe during its first month beginning 1.2days post-explosion and with an average cadence of 1.8days. This gives a clear picture of how various line-forming species are distributed within the outer layers of the ejecta, including that of unburned material (C+O). We follow the evolution of C II absorption features until they diminish near maximum light, showing overlapping regions of burned and unburned material between ejection velocities of 10,000 and 16,000kms-1. This supports the notion that incomplete burning, in addition to progenitor scenarios, is a relevant source of spectroscopic diversity among SNeIa. The observed evolution of the highly Doppler-shifted O I λ7774 absorption features detected within 5days post-explosion indicates the presence of O I with expansion velocities from 11,500 to 21,000kms-1. The fact that some O I is present above C II suggests that SN2011fe may have had an appreciable amount of unburned oxygen within the outer layers of the ejecta. © 2012. The American Astronomical Society. All rights reserved..

Fifty Kingella kingae organisms, isolated from tonsillar cultures of day care center attendees during an 11-month period, and 60 isolates derived from epidemiologically unrelated individuals, including 19 isolates from respiratory carriers and 41 isolates from patients with invasive infections, were typed by immunoblotting, pulsed-field gel electrophoresis, and ribotyping. One strain, defined by unique immunoblotting, pulsed-field gel electrophoresis, and ribotyping patterns, represented 14 day care isolates (28%) and was frequently isolated during the first half of the follow-up period; a second strain represented 23 (46%) isolates and prevailed during the last 5 months. Children frequently carried the same strain continuously or intermittently for weeks or months, when it was replaced by a new strain. Epidemiologically unrelated organisms showed greater variability, and no strain represented >5% of isolates. The present results support person-to-person transmission of K. kingae among young children in the day care setting. [ABSTRACT FROM AUTHOR]

Abstract Background and Purpose Oligodendrocyte (OL) death is important in focal cerebral ischemia. TIMP-3 promotes apoptosis in ischemic neurons by inhibiting proteolysis of TNF-α superfamily of death receptors. Since OLs undergo apoptosis during ischemia, we hypothesized that TIMP-3 contributes to OL death. Methods Middle cerebral artery occlusion (MCAO) was induced in Timp-3 knockout (KO) and wild type (WT) mice with 24 or 72 h of reperfusion. Cell death in white matter was investigated by stereology and TUNEL. Mature or immature OLs were identified using antibodies against glutathione S-transferase-π (GST-π) and galactocerebroside (GalC), respectively. Expression and level of proteins were examined using immunohistochemistry and immunoblotting. Protein activities were determined using a FRET peptide. Results Loss of OL-like cells was detected at 72 h only in WT ischemic white matter where TUNEL showed greater cell death. TIMP-3 expression was increased in WT reactive astrocytes. GST-π was reduced in ischemic white matter of WT mice compared with WT shams with no difference between KO and WT at 72 h. GalC level was significantly increased in both KO and WT ischemic white matter at 72 h. However, the increase in GalC in KO mice was significantly higher than WT; most TUNEL-positive cells in ischemic white matter expressed GalC, suggesting TIMP-3 deficiency protects the immature OLs from apoptosis. There were significantly higher levels of cleaved caspase-3 at 72 h in WT white matter than in KO. Greater expression of MMP-3 and -9 was seen in reactive astrocytes and/or microglia/macrophages in WT at 72 h. We found more microglia/macrophages in WT than in KO, which were the predominant source of increased TNF-α detected in the ischemic white matter. TACE activity was significantly increased in ischemic WT white matter, which was expressed in active microglia/macrophages and OLs. Conclusions Our results suggested that focal ischemia leads to proliferation of immature OLs in white matter and that TIMP-3 contributes to a caspase-3-dependent immature OL death via TNF-α-mediated neuroinflammation. Future studies will be needed to delineate the role of MMP-3 and MMP-9 that were increased in the Timp-3 wild type.

Although climate change is increasing wildfire and smoke events globally, public health messaging and individual access to resources for protection are limited. Individual interventions can be highly effective at reducing wildfire smoke exposure. However, studies related to individual responses to wildfire smoke are limited and demonstrate mixed protective behaviors and risk perception. Our research helps fill this gap by assessing the self-reported behavior of 20 participants during wildfire season in Western Montana from 28 June through 1 November, 2022. We also measured continuous outdoor and indoor fine particulate matter (PM2.5) concentrations at participant residencies during this time period using PurpleAir sensors (PAII-SD, PurpleAir, Inc, USA) while participants took up to 16 self-reported online weekly activity surveys. Mixed-effect Poisson regression models were used to assess associations between exposure variables and participant reported behaviors. These results were compared with end-of-study interview findings. Wildfire smoke impacted days and increased concentrations of PM2.5 were associated with decreased outdoor exercise and opening of windows for ventilation. Interview themes were congruent with the regression analysis, with the additional finding of high portable air cleaner (PAC) use among participants. Additionally, these interviews gave context to both the tradeoffs participants face when making protective decisions and the importance of personal air quality data in increasing awareness about wildfire smoke risks. Future wildfire smoke studies can build off this research by providing personally relevant air quality data and PACs to participants and by improving public health messaging to address the compounding risks of wildfire smoke exposure and heat., Competing Interests: Declarations. Conflict of Interest: There are no conflicts of interest., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Emerging evidence links dietary interventions to favorable multiple sclerosis (MS) outcomes; however, evidence for the efficacy of dietary interventions on functional disability remains sparse. Data from two 12-week, randomized, controlled pilot trials were pooled to investigate the efficacy of a modified Paleolithic diet (Paleo) on functional disability, as assessed by the MS Functional Composite (MSFC), among people diagnosed with MS. Pooled baseline-referenced MSFC scores were calculated from the nine-hole peg test (NHPT), timed 25-foot walk (T25FW), and Paced Auditory Serial Addition Test (PASAT) Z-scores. There was no significant difference in the mean change in MSFC scores between groups ( p = 0.07). In the Paleo group, a significant increase was observed in the MSFC scores ( p = 0.03), NHPT ( p < 0.001), and PASAT ( p = 0.04) Z-scores at 12 weeks, indicating reduced functional disability compared to baseline values. No significant changes were observed within the Control group. Study-specific differences in the MSFC changes between groups were observed. Functional disability was reduced compared to the baseline in the Paleo group, possibly depending on MS type. These results provide preliminary observations on the efficacy of a modified Paleolithic diet for reducing or maintaining functional disability in MS., Competing Interests: Conflicts of Interest: Terry Wahls personally follows and promotes the Wahls™ diet. She has equity interest in the following companies: Dr. Terry Wahls LLC; TZ Press LLC; The Wahls Institute, PLC; FBB Biomed Inc; Levels Health Inc; Foogal Inc.; and the website http://www.terrywahls.com. She also owns the copyright to the books Minding My Mitochondria (2nd edition), The Wahls Protocol, and The Wahls Protocol Cooking for Life and the trademarks The Wahls Protocol® and Wahls™ diet, Wahls Paleo™ diet, and Wahls Paleo Plus™ diets (the Wahls elimination diet is not trademarked). She has completed grant funding from the National Multiple Sclerosis Society for the Dietary Approaches to Treating Multiple Sclerosis Related Fatigue Study. She has financial relationships with Master Health inc., Vibrant America LLC, Standard Processed Inc., and the Institute for Functional Medicine. She receives royalty payments from Penguin Random House. Terry Wahls has conflict of interest management plans in place with the University of Iowa and the Iowa City VA Healthcare System. All the other authors report no personal or financial conflicts of interest in this work.

Residential wood burning has both practical and traditional value among many indigenous communities of the United States Mountain West, although household biomass burning also results in emissions that are harmful to health. In a household-level three-arm placebo-controlled randomized trial we tested the efficacy of portable filtration units and education interventions on improving pulmonary function and blood pressure measures among elder participants that use wood stoves for residential heating. A total of 143 participants were assigned to the Education (n=49), Filter (n=47), and Control (n=47) arms. Blood pressure and spirometry measures were collected multiple times during a per-intervention winter period and during a follow-up post-intervention winter period. Despite strong PM 2.5 exposure reduction results with the Filter arm (50% lower compared to Control arm), neither this intervention nor the Education intervention translated to improvements in the selected health measures among this population with a mixture of chronic conditions. Intention to treat analysis failed to demonstrate evidence that either of the intervention arms had beneficial effects on the blood pressure or the spirometry measures. Post-hoc evaluation of effect modification for blood pressure and spirometry outcomes did not reveal any interaction influence on the outcomes according to sex, residential smoking, chronic disease history and study area.

Background: Acute viral bronchiolitis is the most common reason for hospitalization of infants in the USA. Infants hospitalized for bronchiolitis are at high risk for recurrent respiratory symptoms and wheeze in the subsequent year, and longer-term adverse respiratory outcomes such as persistent childhood asthma. There are no effective secondary prevention strategies. Multiple factors, including air pollutant exposure, contribute to risk of adverse respiratory outcomes in these infants. Improvement in indoor air quality following hospitalization for bronchiolitis may be a prevention opportunity to reduce symptom burden. Use of stand-alone high efficiency particulate air (HEPA) filtration units is a simple method to reduce particulate matter ≤ 2.5 µm in diameter (PM 2.5 ), a common component of household air pollution that is strongly linked to health effects., Methods: BREATHE is a multi-center, parallel, double-blind, randomized controlled clinical trial. Two hundred twenty-eight children < 12 months of age hospitalized for the first time with bronchiolitis will participate. Children will be randomized 1:1 to receive a 24-week home intervention with filtration units containing HEPA and carbon filters (in the child's sleep space and a common room) or to a control group with units that do not contain HEPA and carbon filters. The primary objective is to determine if use of HEPA filtration units reduces respiratory symptom burden for 24 weeks compared to use of control units. Secondary objectives are to assess the efficacy of the HEPA intervention relative to control on (1) number of unscheduled healthcare visits for respiratory complaints, (2) child quality of life, and (3) average PM 2.5 levels in the home., Discussion: We propose to test the use of HEPA filtration to improve indoor air quality as a strategy to reduce post-bronchiolitis respiratory symptom burden in at-risk infants with severe bronchiolitis. If the intervention proves successful, this trial will support use of HEPA filtration for children with bronchiolitis to reduce respiratory symptom burden following hospitalization., Trial Registration: NCT05615870. Registered on November 14, 2022., (© 2024. The Author(s).)

Background: Research has shown that cultural activities may bring about improved health. However, large-scale quantitative analyses on cultural engagement and biomarkers are lacking to date. As a result, the mechanisms through which cultural activities may be associated with health are unclear., Aim: Test quantitative associations between cultural engagement pattern (including active and passive engagement in arts, sports, and heritage activities) and indicators of biological dysregulation in a large dataset., Subjects and Methods: Understanding Society data were used to conduct cross-sectional linear regression analyses between a data-driven latent class model of cultural engagement and indicators of anthropometric, cardiovascular, metabolic, immune, and neuroendocrine function. Analyses were adjusted for age, gender, ethnicity, childcare responsibility, urbanicity, leisure time satisfaction, capacity-related factors, socioeconomic position, social and economic capital indicators, physical activity, and medication use., Results: More culturally participants had better indicators of biological health, such as lower waist circumference and fibrinogen blood concentration. Specific associations between cultural engagement pattern and the different biological outcomes were also observed. The associations were explained in part by correlated factors (accounting for around half of the association)., Conclusions: Cultural engagement is cross-sectionally associated with biomarkers, although the characteristics of people who engage with culture are an important consideration when interpreting these findings.

Background/aims: Wildfire air pollution is a growing public health concern as wildfires increase in size, intensity, and duration in the United States. The public is often encouraged to stay indoors during wildfire smoke events to reduce exposure. However, there is limited information on how much wildfire smoke infiltrates indoors at residences and what household/behavioral characteristics contribute to higher infiltration. We assessed fine particulate matter (PM 2.5 ) infiltration into Western Montana residences during wildfire season., Methods: We measured continuous outdoor and indoor PM 2.5 concentrations from July-October 2022 at 20 residences in Western Montana during wildfire season using low-cost PM 2.5 sensors. We used paired outdoor/indoor PM 2.5 data from each household to calculate infiltration efficiency (F inf ; range 0-1; higher values indicate more outdoor PM 2.5 infiltration to the indoor environment) using previously validated methods. Analyses were conducted for all households combined and for various household subgroups., Results: Median (25th percentile, 75th percentile) daily outdoor PM 2.5 at the households was 3.7 μg/m 3 (2.1, 7.1) during the entire study period and 29.0 μg/m 3 (19.0, 49.4) during a 2-week period in September impacted by wildfire smoke. Median daily indoor PM 2.5 at the households was 2.5 μg/m 3 (1.3, 5.5) overall and 10.4 μg/m 3 (5.6, 21.0) during the wildfire period. Overall F inf was 0.34 (95 % Confidence Interval [95%CI]: 0.33, 0.35) with lower values during the wildfire period (0.32; 95%CI: 0.28, 0.36) versus non-wildfire period (0.39; 95%CI: 0.37, 0.42). Indoor PM 2.5 concentrations and F inf varied substantially across household subgroups such as household income, age of the home, presence of air conditioning units, and use of portable air cleaners., Conclusions: Indoor PM 2.5 was substantially higher during wildfire-impacted periods versus the rest of the study. Indoor PM 2.5 and F inf were highly variable across households. Our results highlight potentially modifiable behaviors and characteristics that can be used in targeted intervention strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

To Bourdieu, interaction with culture has symbolic power and drives the manifestation of social stratification. Many have adapted his theory and methodology, developing new models of cultural engagement. Here, to further integrate these theoretical and methodological approaches, Bourdieu's tools were used to operationalise and interpret a Latent Class Analysis of cultural engagement in the Understanding Society dataset. Six classes of increasing engagement were established, and were increasingly correlated with youth, capital and social advantage. However, some qualitative differences in engagement were also seen. The classes also varied by which characteristics correlated with membership. For example, economic capital was associated with sports engagement, while advantaged social position was associated with broad-scale engagement. Overall, this analysis combined Bourdieusian theory with contemporary methodology in the largest representative UK dataset and highlights the broader relevance of cultural engagement patterns in indicating (and possibly generating) status, identity, capital and social position., (© The Author(s) 2022.)

Background: Native Americans living in rural areas often rely upon wood stoves for home heating that can lead to elevated indoor concentrations of fine particulate matter (PM 2.5 ). Wood stove use is associated with adverse health outcomes, which can be a particular risk in vulnerable populations including older adults., Objectives: We assessed the impact of portable air filtration units and educational approaches that incorporated elements of traditional knowledge on indoor and personal PM 2.5 concentrations among rural, Native American elder households with wood stoves., Methods: EldersAIR was a three-arm, pre-post randomized trial among rural households from the Navajo Nation and Nez Perce Tribe in the United States. We measured personal and indoor PM 2.5 concentrations over 2-day sampling periods on up to four occasions across two consecutive winter seasons in elder participant homes. We assessed education and air filtration intervention efficacy using linear mixed models., Results: Geometric mean indoor PM 2.5 concentrations were 50.5 % lower (95 % confidence interval: -66.1, -27.8) in the air filtration arm versus placebo, with similar results for personal PM 2.5 . Indoor PM 2.5 concentrations among education arm households were similar to placebo, although personal PM 2.5 concentrations were 33.3 % lower for the education arm versus placebo (95 % confidence interval: -63.2, 21.1)., Significance: The strong partnership between academic and community partners helped facilitate a culturally acceptable approach to a clinical trial intervention within the study communities. Portable air filtration units can reduce indoor PM 2.5 that originates from indoor wood stoves, and this finding was supported in this study. The educational intervention component was meaningful to the communities, but did not substantially impact indoor PM 2.5 relative to placebo. However, there is evidence that the educational interventions reduced indoor PM 2.5 in some subsets of the study households. More study is required to determine ways to optimize educational interventions within Native American communities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Wildfire events are increasing across the globe. The smoke generated as a result of this changing fire landscape is potentially more toxic than air pollution from other ambient sources, according to recent studies. This is especially concerning for populations of humans or animals that live downwind of areas that burn frequently, given that ambient exposure to wildfire smoke cannot be easily eliminated. We hypothesized that a significant indoor air pollution risk existed for laboratory animal facilities located proximal to fire-prone areas. Here, we measured real time continuous outdoor and indoor air quality for 28 days at a laboratory animal facility located in the Rocky Mountain region. We demonstrated that during a wildfire event, the indoor air quality of this animal facility is influenced by ambient smoke events. The daily average indoor fine particulate matter value in an animal room exceeded the Environmental Protection Agency's ambient annual standard 14% of the time and exceeded the World Health Organization's ambient annual guideline 71% of the time. We further show that specialized cage filtration systems are capable of mitigating air pollution penetrance and could improve an animal's microenvironment. The potential effects for laboratory animal physiology that occur in response to the exposure levels and durations measured in this study remain to be determined; yet, even acute wildfire exposure events have been previously correlated with significant differences in gene regulatory and metabolic processes in vivo. We believe these findings warrant consideration for indoor laboratory animal facility air quality monitoring and development of smoke exposure prevention and response protocols, especially among facilities located downwind of fire-prone landscapes.

Introduction: Household air pollution from cooking-related biomass combustion remains a leading risk factor for global health. Black carbon (BC) is an important component of particulate matter (PM) in household air pollution. We evaluated the impact of the engineered, wood-burning Justa stove intervention on BC concentrations., Methods: We conducted a 3-year stepped-wedge randomized controlled trial with 6 repeated visits among 230 female primary cooks in rural Honduras. Participants used traditional stoves at baseline and were randomized to receive the Justa after visit 2 or after visit 4. At each visit, we measured 24-hour gravimetric personal and kitchen fine PM (PM 2.5 ) concentrations and estimated BC mass concentrations (Sootscan Transmissometer). We conducted intent-to-treat analyses using linear mixed models with natural log-transformed 24-hour personal and kitchen BC., Results: BC concentrations were reduced for households assigned to the Justa vs. traditional stoves: e.g., personal BC geometric mean (GSD), 3.6 μg/m 3 (6.4) vs. 11.5 μg/m 3 (4.6), respectively. Following the intervention, we observed 53% (95% CI: 35-65%) lower geometric mean personal BC concentrations and 76% (95% CI: 66-83%) lower geometric mean kitchen BC concentrations., Conclusions: The Justa stove intervention substantially reduced BC concentrations, mitigating household air pollution and potentially benefitting human and climate health., Competing Interests: Two of the authors, Sebastian Africano of Trees, Water & People (TWP), and Anibal Benjamin Osorto Pinel of Asociación Hondureña para el Desarrollo (AHDESA), are members of the implementing non-governmental organizations that deploy the Justa stove. Publications like this are often used to support their cookstove technology in TWP and AHDESA blogs, articles, and grant proposals, which may lead to future funding of these initiatives by individual and/or institutional supporters.

Wildfire activity is increasing in parts of the world where extreme drought and warming temperatures contribute to fireprone conditions, including the western United States. The elderly are among the most vulnerable, and those in long-term care with preexisting conditions have added risk for adverse health outcomes from wildfire smoke exposure. In this study, we report continuous co-located indoor and outdoor fine particulate matter (PM 2.5 ) measurements at four skilled nursing facilities in the western United States. Throughout the year 2020, over 8000 h of data were collected, which amounted to approximately 300 days of indoor and outdoor sampling at each facility. The highest indoor 24 h average PM 2.5 recorded at each facility was 43.6 µg/m 3 , 103.2 µg/m 3 , 35.4 µg/m 3 , and 202.5 µg/m 3 , and these peaks occurred during the wildfire season. The indoor-to-outdoor PM 2.5 ratio and calculated infiltration efficiencies indicated high variation in the impact of wildfire events on Indoor Air Quality between the four facilities. Notably, infiltration efficiency ranged from 0.22 to 0.76 across the four facilities. We propose that this variability is evidence that PM 2.5 infiltration may be impacted by modifiable building characteristics and human behavioral factors, and this should be addressed in future studies., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Millions of rural U.S. households are heated with wood stoves. Wood stove use can lead to high indoor concentrations of fine particulate matter [airborne particles ≤ 2.5 μ m in aerodynamic diameter ( PM 2.5 )] and is associated with lower respiratory tract infection (LRTI) in children., Objectives: We assessed the impact of low-cost educational and air filtration interventions on childhood LRTI and indoor PM 2.5 in rural U.S. homes with wood stoves., Methods: The Kids Air Quality Interventions for Reducing Respiratory Infections (KidsAIR) study was a parallel three-arm (education, portable air filtration unit, control), post-only randomized trial in households from Alaska, Montana, and Navajo Nation (Arizona and New Mexico) with a wood stove and one or more children < 5  years of age. We tracked LRTI cases for two consecutive winter seasons and measured indoor PM 2.5 over a 6-d period during the first winter. We assessed results using two analytical frameworks: a ) intervention efficacy on LRTI and PM 2.5 (intent-to-treat), and b ) association between PM 2.5 and LRTI (exposure-response)., Results: There were 61 LRTI cases from 14,636 child-weeks of follow-up among 461 children. In the intent-to-treat analysis, children in the education arm [ odds ratio  ( OR ) = 0.98 ; 95% confidence interval (CI): 0.35, 2.72] and the filtration arm ( OR = 1.23 ; 95% CI: 0.46, 3.32) had similar odds of LRTI vs. control. Geometric mean PM 2.5 concentrations were similar to control in the education arm (11.77% higher; 95% CI: - 16.57 , 49.72) and air filtration arm (6.96% lower; 95% CI: - 30.50 , 24.55). In the exposure-response analysis, odds of LRTI were 1.45 times higher (95% CI: 1.02, 2.05) per interquartile range ( 25   μ g / m 3 ) increase in mean indoor PM 2.5 ., Discussion: We did not observe meaningful differences in LRTI or indoor PM 2.5 in the air filtration or education arms compared with the control arm. Results from the exposure-response analysis provide further evidence that biomass air pollution adversely impacts childhood LRTI. Our results highlight the need for novel, effective intervention strategies in households heated with wood stoves. https://doi.org/10.1289/EHP9932.

Household air pollution is a leading risk factor for morbidity and premature mortality. Numerous cookstoves have been developed to reduce household air pollution, but it is unclear whether such cookstoves meaningfully improve health. In a controlled exposure study with a crossover design, we assessed the effect of pollution emitted from multiple cookstoves on acute differences in blood lipids and inflammatory biomarkers. Participants (n = 48) were assigned to treatment sequences of exposure to air pollution emitted from five cookstoves and a filtered-air control. Blood lipids and inflammatory biomarkers were measured before and 0, 3, and 24 hours after treatments. Many of the measured outcomes had inconsistent results. However, compared to control, intercellular adhesion molecule-1 was higher 3 hours after all treatments, and C-reactive protein and serum amyloid-A were higher 24 hours after the highest treatment. Our results suggest that short-term exposure to cookstove air pollution can increase inflammatory biomarkers within 24 hours.

Household heating using wood stoves is common practice in many rural areas of the United States (US) and can lead to elevated concentrations of indoor fine particulate matter (PM 2.5 ). We collected 6-day measures of indoor PM 2.5 during the winter and evaluated household and stove-use characteristics in homes at three rural and diverse study sites. The median indoor PM 2.5 concentration across all homes was 19 µg/m 3 , with higher concentrations in Alaska (median = 30, minimum = 4, maximum = 200, n = 10) and Navajo Nation homes (median = 29, minimum = 3, maximum = 105, n = 23) compared with Montana homes (median = 16, minimum = 2, maximum = 139, n = 59). Households that had not cleaned the chimney within the past year had 65% higher geometric mean PM 2.5 compared to those with chimney cleaned within 6 months (95% confidence interval [CI]: -1, 170). Based on a novel wood stove grading method, homes with low-quality and medium-quality stoves had substantially higher PM 2.5 compared to homes with higher-quality stoves (186% higher [95% CI: 32, 519] and 161% higher; [95% CI:27, 434], respectively). Our findings highlight the need for, and complex nature of, regionally appropriate interventions to reduce indoor air pollution in rural wood-burning regions. Higher-quality stoves and behavioral practices such as regular chimney cleaning may help improve indoor air quality in such homes., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Trial Design: We evaluated the impact of a biomass stove intervention on fine particulate matter (PM 2.5 ) concentrations using an individual-level, stepped-wedge randomized trial., Methods: We enrolled 230 women in rural Honduran households using traditional biomass stoves and randomly allocated them to one of two study arms. The Justa stove, the study intervention, was locally-sourced, wood-burning, and included an engineered combustion chamber and chimney. At each of 6 visits over 3 years, we measured 24-hour gravimetric personal and kitchen PM 2.5 concentrations. Half of the households received the intervention after Visit 2 and half after Visit 4. We conducted intent-to-treat analyses to evaluate the intervention effect using linear mixed models with log-transformed kitchen or personal PM 2.5 (separately) as the dependent variable, adjusting for time. We also compared PM 2.5 concentrations to World Health Organization (WHO) guidelines., Results: Arms 1 and 2 each had 115 participants with 664 and 632 completed visits, respectively. Median 24-hour average personal PM 2.5 exposures were 81 μg/m 3 (25th-75th percentile: 50-141 μg/m 3 ) for the traditional stove condition (n=622) and 43 μg/m 3 (25th-75th percentile: 27-73 μg/m 3 ) for the Justa stove condition (n=585). Median 24-hour average kitchen concentrations were 178 μg/m 3 (25th-75th percentile: 69-440 μg/m 3 ; n=629) and 53 μg/m 3 (25th-75th percentile: 29-103 μg/m 3 ; n=578) for the traditional and Justa stove conditions, respectively. The Justa intervention resulted in a 32% reduction in geometric mean personal PM 2.5 (95% confidence interval [CI]: 20-43%) and a 56% reduction (95% CI: 46-65%) in geometric mean kitchen PM 2.5 . During rainy and dry seasons, 53% and 41% of participants with the Justa intervention had 24-hour average personal PM 2.5 exposures below the WHO interim target-3 guideline (37.5 μg/m 3 ), respectively., Conclusion: The Justa stove intervention substantially lowered personal and kitchen PM 2.5 and may be a provisional solution that is feasible for Latin American communities where cleaner fuels may not be available, affordable, or acceptable for some time. Clinicaltrials.gov: NCT02658383., Competing Interests: Declaration of competing interest Two of the authors, Sebastian Africano of Trees, Water & People (TWP), and Anibal Benjamin Osorto Pinel of Asociación Hondureña para el Desarrollo (AHDESA), are members of the implementing non-governmental organizations that deploy the cookstove technology presented in this manuscript. Publications like this are often used to support their cookstove technology in TWP and AHDESA blogs, articles, and grant proposals, which may lead to future funding of these initiatives by individual and/or institutional supporters of the respective organizations. As such, we disclose this information., (Copyright © 2021 Elsevier B.V. All rights reserved.)

We report mean severe acute respiratory syndrome coronavirus 2 serial intervals for Montana, USA, from 583 transmission pairs; infectors' symptom onset dates occurred during March 1-July 31, 2020. Our estimate was 5.68 (95% CI 5.27-6.08) days, SD 4.77 (95% CI 4.33-5.19) days. Subperiod estimates varied temporally by nonpharmaceutical intervention type and fluctuating incidence.

This experimental study reveals intriguing thermoelectric effects and devices in epitaxial bismuthene, two-dimensional (2D) bismuth with thickness ⩽30 nm, on Si (111). Bismuthene exhibits interesting anisotropic Seebeck coefficients varying 2-5 times along different crystal orientations, implying the existence of a puckered atomic structure like black phosphorus. An absolute value of Seebeck coefficient up to 237 μV K -1 sets a record for elemental Bi ever measured to the best of our knowledge. Electrical conductivity of bismuthene can reach up to 4.6 × 10 4 S m -1 , which is sensitive to thickness and magnetic field. Along with a desired low thermal conductivity ∼1.97 W m -1 K that is 20% of its bulk form, the first experimental zT value at room temperature for bismuthene was measured ∼10 -2 , which is much higher than many other VA Xenes and comparable to its bulk compounds. Above results suggest a mixed buckled and puckered Bi atomic structure for epitaxial 2D bismuth on Si (111). Our work paves the way to explore potential applications, such as heat flux sensor, energy converting devices and so on for bismuthene.

Household air pollution from combustion of solid fuels is an important risk factor for morbidity and mortality, causing an estimated 2.6 million premature deaths globally in 2016. Self-reported health symptoms are a meaningful measure of quality of life, however, few studies have evaluated symptoms and quantitative measures of exposure to household air pollution. We assessed the cross-sectional association of self-reported symptoms and exposures to household air pollution among women in rural Honduras using stove type (traditional [n = 76]; cleaner-burning Justa [n = 74]) and 24-hour average personal and kitchen fine particulate matter (PM 2.5 ) concentrations. The odds of prevalent symptoms were higher among women using traditional stoves vs Justa stoves (e.g. headache: odds ratio = 2.23; 95% confidence interval = 1.13-4.39). Associations between symptoms and measured PM 2.5 were generally consistent with the null. These results add to the evidence suggesting reduced exposures and better health-related quality of life among women using cleaner-burning biomass stoves.

Background: Exposure to household air pollution generated as a result of cooking and heating is a leading contributor to global disease. The effects of cookstove-generated air pollution on adult lung function, however, remain uncertain. Objectives: We investigated acute responses in lung function following controlled exposures to cookstove-generated air pollution. Methods: We recruited 48 healthy adult volunteers to undergo six two-hour treatments: a filtered-air control and emissions from five different stoves with fine particulate matter (PM 2.5 ) targets from 10 to 500 µg/m 3 . Spirometry was conducted prior to exposure and immediately, and three and 24 h post-exposure. Mixed-effect models were used to estimate differences in post-exposure lung function for stove treatments versus control. Results: Immediately post-exposure, lung function was lower compared to the control for the three highest PM 2.5 -level stoves. The largest differences were for the fan rocket stove (target 250 µg/m 3 ; forced vital capacity (FVC): -60 mL, 95% confidence interval (95% CI) -135, 15; forced expiratory volume (FEV 1 ): -51 mL, 95% CI -117, 16; mid-expiratory flow (FEF 25-75 ): -116 mL/s, 95% CI -239, 8). At 3 h post-exposure, lung function was lower compared to the control for all stove treatments; effects were of similar magnitude for all stoves. At 24 h post-exposure, results were consistent with a null association for FVC and FEV 1 ; FEF 25-75 was lower relative to the control for the gasifier, fan rocket, and three stone fire. Conclusions: Patterns suggesting short-term decreases in lung function follow from exposure to cookstove air pollution even for stove exposures with low PM 2.5 levels.

Household air pollution emitted from solid-fuel cookstoves used for domestic cooking is a leading risk factor for morbidity and premature mortality globally. There have been attempts to design and distribute lower emission cookstoves, yet it is unclear if they meaningfully improve health. Using a crossover design, we assessed differences in central aortic hemodynamics and arterial stiffness following controlled exposures to air pollution emitted from five different cookstove technologies compared to a filtered air control. Forty-eight young, healthy participants were assigned to six 2-h controlled treatments of pollution from five different cookstoves and a filtered air control. Each treatment had a target concentration for fine particulate matter: filtered air control = 0 μg/m 3 , liquefied petroleum gas = 10 μg/m 3 , gasifier = 35 μg/m 3 , fan rocket = 100 μg/m 3 , rocket elbow = 250 μg/m 3 , three stone fire = 500 μg/m 3 . Pulse wave velocity (PWV), central augmentation index (AIx), and central pulse pressure (CPP) were measured before and at three time points after each treatment (0, 3, and 24 h). Linear mixed models were used to assess differences in the outcomes for each cookstove treatment compared to control. PWV and CPP were marginally higher 24 h after all cookstove treatments compared to control. For example, PWV was 0.15 m/s higher (95% confidence interval: -0.02, 0.31) and CPP was 0.6 mmHg higher (95% confidence interval: -0.8, 2.1) 24 h after the three stone fire treatment compared to control. The magnitude of the differences compared to control was similar across all cookstove treatments. PWV and CPP had no consistent trends at the other post-treatment time points (0 and 3 h). No consistent trends were observed for AIx at any post-treatment time point. Our findings suggest higher levels of PWV and CPP within 24 h after 2-h controlled treatments of pollution from five different cookstove technologies. The similar magnitude of the differences following each cookstove treatment compared to control may indicate that acute exposures from even the cleanest cookstove technologies can adversely impact these subclinical markers of cardiovascular health, although differences were small and may not be clinically meaningful., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background Exposure to air pollution from solid fuel used in residential cookstoves is considered a leading environmental risk factor for disease globally, but evidence for this relationship is largely extrapolated from literature on smoking, secondhand smoke, and ambient fine particulate matter ( PM 2.5 ). Methods and Results We conducted a controlled human-exposure study (STOVES [the Subclinical Tests on Volunteers Exposed to Smoke] Study) to investigate acute responses in blood pressure following exposure to air pollution emissions from cookstove technologies. Forty-eight healthy adults received 2-hour exposures to 5 cookstove treatments (three stone fire, rocket elbow, fan rocket elbow, gasifier, and liquefied petroleum gas), spanning PM 2.5 concentrations from 10 to 500 μg/m 3 , and a filtered air control (0 μg/m 3 ). Thirty minutes after exposure, systolic pressure was lower for the three stone fire treatment (500 μg/m 3 PM 2.5 ) compared with the control (-2.3 mm Hg; 95% CI, -4.5 to -0.1) and suggestively lower for the gasifier (35 μg/m 3 PM 2.5 ; -1.8 mm Hg; 95% CI , -4.0 to 0.4). No differences were observed at 3 hours after exposure; however, at 24 hours after exposure, mean systolic pressure was 2 to 3 mm Hg higher for all treatments compared with control except for the rocket elbow stove. No differences were observed in diastolic pressure for any time point or treatment. Conclusions Short-term exposure to air pollution from cookstoves can elicit an increase in systolic pressure within 24 hours. This response occurred across a range of stove types and PM 2.5 concentrations, raising concern that even low-level exposures to cookstove air pollution may pose adverse cardiovascular effects.

Background: Growing evidence links household air pollution exposure from biomass-burning cookstoves to cardiometabolic disease risk. Few randomized controlled interventions of cookstoves (biomass or otherwise) have quantitatively characterized changes in exposure and indicators of cardiometabolic health, a growing and understudied burden in low- and middle-income countries (LMICs). Ideally, the solution is to transition households to clean cooking, such as with electric or liquefied petroleum gas stoves; however, those unable to afford or to access these options will continue to burn biomass for the foreseeable future. Wood-burning cookstove designs such as the Justa (incorporating an engineered combustion zone and chimney) have the potential to substantially reduce air pollution exposures. Previous cookstove intervention studies have been limited by stove types that did not substantially reduce exposures and/or by low cookstove adoption and sustained use, and few studies have incorporated community-engaged approaches to enhance the intervention., Methods/design: We conducted an individual-level, stepped-wedge randomized controlled trial with the Justa cookstove intervention in rural Honduras. We enrolled 230 female primary cooks who were not pregnant, non-smoking, aged 24-59 years old, and used traditional wood-burning cookstoves at baseline. A community advisory board guided survey development and communication with participants, including recruitment and retention strategies. Over a 3-year study period, participants completed 6 study visits approximately 6 months apart. Half of the women received the Justa after visit 2 and half after visit 4. At each visit, we measured 24-h gravimetric personal and kitchen fine particulate matter (PM 2.5 ) concentrations, qualitative and quantitative cookstove use and adoption metrics, and indicators of cardiometabolic health. The primary health endpoints were blood pressure, C-reactive protein, and glycated hemoglobin. Overall study goals are to explore barriers and enablers of new cookstove adoption and sustained use, compare health endpoints by assigned cookstove type, and explore the exposure-response associations between PM 2.5 and indicators of cardiometabolic health., Discussion: This trial, utilizing an economically feasible, community-vetted cookstove and evaluating endpoints relevant for the major causes of morbidity and mortality in LMICs, will provide critical information for household air pollution stakeholders globally., Trial Registration: ClinicalTrials.gov Identifier NCT02658383 , posted January 18, 2016, field work completed May 2018. Official title, "Community-Based Participatory Research: A Tool to Advance Cookstove Interventions." Principal Investigator Maggie L. Clark, Ph.D. Last update posted July 12, 2018.

Cookstoves emit many pollutants that are harmful to human health and the environment. However, most of the existing scientific literature focuses on fine particulate matter (PM 2.5 ) and carbon monoxide (CO). We present an extensive data set of speciated air pollution emissions from wood, charcoal, kerosene, and liquefied petroleum gas (LPG) cookstoves. One-hundred and twenty gas- and particle-phase constituents-including organic carbon, elemental carbon (EC), ultrafine particles (10-100 nm), inorganic ions, carbohydrates, and volatile/semivolatile organic compounds (e.g., alkanes, alkenes, alkynes, aromatics, carbonyls, and polycyclic aromatic hydrocarbons (PAHs))-were measured in the exhaust from 26 stove/fuel combinations. We find that improved biomass stoves tend to reduce PM 2.5 emissions; however, certain design features (e.g., insulation or a fan) tend to increase relative levels of other coemitted pollutants (e.g., EC ultrafine particles, carbonyls, or PAHs, depending on stove type). In contrast, the pressurized kerosene and LPG stoves reduced all pollutants relative to a traditional three-stone fire (≥93% and ≥79%, respectively). Finally, we find that PM 2.5 and CO are not strong predictors of coemitted pollutants, which is problematic because these pollutants may not be indicators of other cookstove smoke constituents (such as formaldehyde and acetaldehyde) that may be emitted at concentrations that are harmful to human health.

To ascertain attitudes to resourcing, collaboration and publication in toxicology, a survey was developed and distributed to British Toxicology Society (BTS) members. The survey comprised 14 questions with 5 response options (strongly agree; agree; conflicted; disagree; strongly disagree) and a free text box. One hundred completed surveys were received by the cut-off date for data analysis. Unsurprisingly, 60% of participants disagreed or strongly disagreed that toxicology research is adequately funded in the UK; only 12% agreed with this statement. A similar proportion of participants (53%) disagreed with the statement that funding councils give equal opportunity to toxicology whereas 31% were conflicted on this point. An overwhelming 97% of respondents agreed that collaboration is important in driving toxicology research whereas only 38% agreed that competition is important. When this question was broadened out beyond the discipline of toxicology, a similar profile was seen suggesting that participants held similar views on toxicology versus other types of research. Many respondents were conflicted regarding the role of competition both in toxicology and in other research disciplines. Free text comments suggested that some competition is good to drive quality but can be counterproductive when competing for limited resources. Most participants were in favour of making toxicology research data openly available (86%) and in favour of open access publication (89%) although there were reservations about the cost of open access. Many (60%) thought the current system of peer review is fair but 65% also supported the idea of double-blind peer review (where both reviewer and author are anonymized). Others suggested a step in the opposite direction towards increased transparency (revealing and holding reviewers to account) would be preferable. Overall, there was a broad theme in free text responses that the need for experienced toxicologists has increased at a time when training and investment in the discipline has declined. However, not all respondents held that view with some noting that toxicology both as a research and as an applied discipline is strong within the UK scientific community.

From animal research through adverse events in clinical trials to health scares around food contamination, toxicology has frequently been a focus of scientific and societal concern. As these concerns shift with each new drug, new technology or public health scare, how can toxicology stay current, relevant and ethical? Two of the biggest ethical challenges in pharmaceutical toxicology are the use of animals in testing and the high safety-related attrition rates in new drug development. Both of these require progress in the discipline that will only be driven by research funding. Yet, very little is invested in these two fields compared with investment in new efficacy models, new disease targets and new technologies. How can this be addressed? Here, we explore current paradigms in toxicology that may have the potential for perceived or actual unethical ramifications. We discuss the underpinnings of such practices and make recommendations for change around peer review, resourcing, transparency and data sharing. These ideas build on the analysis presented in the 2004 Paton Prize lecture (Purchase, 2004) where issues around conflict of interest (COI), collaboration and competition in the context of ethical behaviours were highlighted. These areas are clearly relevant to many aspects of scientific research but here we focus on toxicology and specifically toxicology in the pharmaceutical industry.

As the focus of applied research in topological insulators (TI) evolves, the need to synthesize large-area TI films for practical device applications takes center stage. However, constructing scalable and adaptable processes for high-quality TI compounds remains a challenge. To this end, a versatile van der Waals epitaxy (vdWE) process for custom-feature bismuth telluro-sulfide TI growth and fabrication is presented, achieved through selective-area fluorination and modification of surface free-energy on mica. The TI features grow epitaxially in large single-crystal trigonal domains, exhibiting armchair or zigzag crystalline edges highly oriented with the underlying mica lattice and only two preferred domain orientations mirrored at 180°. As-grown feature thickness dependence on lateral dimensions and denuded zones at boundaries are observed, as explained by a semiempirical two-species surface migration model with robust estimates of growth parameters and elucidating the role of selective-area surface modification. Topological surface states contribute up to 60% of device conductance at room temperature, indicating excellent electronic quality. High-yield microfabrication and the adaptable vdWE growth mechanism with readily alterable precursor and substrate combinations lend the process versatility to realize crystalline TI synthesis in arbitrary shapes and arrays suitable for facile integration with processes ranging from rapid prototyping to scalable manufacturing.

We report the first direct dry transfer of a single-crystalline thin film grown by molecular beam epitaxy. A double cantilever beam fracture technique was used to transfer epitaxial bismuth thin films grown on silicon (111) to silicon strips coated with epoxy. The transferred bismuth films retained electrical, optical, and structural properties comparable to the as-grown epitaxial films. Additionally, we isolated the bismuth thin films on freestanding flexible cured-epoxy post-transfer. The adhesion energy at the bismuth/silicon interface was measured to be ∼1 J/m 2 , comparable to that of exfoliated and wet transferred graphene. This low adhesion energy and ease of transfer is unexpected for an epitaxially grown film and may enable the study of bismuth's unique electronic and spintronic properties on arbitrary substrates. Moreover, this method suggests a route to integrate other group-V epitaxial films (i.e., phosphorus) with arbitrary substrates, as well as potentially to isolate bismuthene, the atomic thin-film limit of bismuth.