Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread within the human population. Although SARS-CoV-2 is a novel coronavirus, most humans had been previously exposed to ...other antigenically distinct common seasonal human coronaviruses (hCoVs) before the coronavirus disease 2019 (COVID-19) pandemic. Here, we quantified levels of SARS-CoV-2-reactive antibodies and hCoV-reactive antibodies in serum samples collected from 431 humans before the COVID-19 pandemic. We then quantified pre-pandemic antibody levels in serum from a separate cohort of 251 individuals who became PCR-confirmed infected with SARS-CoV-2. Finally, we longitudinally measured hCoV and SARS-CoV-2 antibodies in the serum of hospitalized COVID-19 patients. Our studies indicate that most individuals possessed hCoV-reactive antibodies before the COVID-19 pandemic. We determined that ∼20% of these individuals possessed non-neutralizing antibodies that cross-reacted with SARS-CoV-2 spike and nucleocapsid proteins. These antibodies were not associated with protection against SARS-CoV-2 infections or hospitalizations, but they were boosted upon SARS-CoV-2 infection.
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•Some humans possessed cross-reactive SARS-CoV-2 antibodies prior to the pandemic•Pre-pandemic SARS-CoV-2 reactive antibodies are not associated with protection•Antibodies to a related betacoronavirus are boosted upon SARS-CoV-2 infection
Analysis of human serum samples before and after the onset of the COVID-19 pandemic show that antibodies against common seasonal human coronaviruses are cross-reactive against SARS-CoV-2 but do not confer cross-protection against infection or hospitalization.
In this research, the authors sought to characterize the incidence and extent of cerebrovascular lesions after penetrating brain injury in a civilian population and to compare the diagnostic value of ...head computed tomography angiography (CTA) and digital subtraction angiography (DSA) in their diagnosis.
This was a prospective multicenter cohort study of patients with penetrating brain injury due to any mechanism presenting at two academic medical centers over a 3-year period (May 2020 to May 2023). All patients underwent both CTA and DSA. The sensitivity and specificity of CTA was calculated, with DSA considered the gold standard. The number of DSA studies needed to identify a lesion requiring treatment that had not been identified on CTA was also calculated.
A total of 73 patients were included in the study, 33 of whom had at least 1 penetrating cerebrovascular injury, for an incidence of 45.2%. The injuries included 13 pseudoaneurysms, 11 major arterial occlusions, 9 dural venous sinus occlusions, 8 dural arteriovenous fistulas, and 6 carotid cavernous fistulas. The sensitivity of CTA was 36.4%, and the specificity was 85.0%. Overall, 5.6 DSA studies were needed to identify a lesion requiring treatment that had not been identified with CTA.
Cerebrovascular injury is common after penetrating brain injury, and CTA alone is insufficient to diagnosis these injuries. Patients with penetrating brain injuries should routinely undergo DSA.
BACKGROUND:Numerous studies have reported favorable outcomes using drug-coated balloons (DCBs) for treatment of symptomatic peripheral artery disease of the superficial femoral and popliteal ...arteries. However, the treatment effect compared with an uncoated balloon has differed greatly among the randomized trials, with better outcomes observed with higher-dose DCBs. This European trial was designed to assess the safety and effectiveness of a next-generation low-dose (2-µg/mm surface dose of paclitaxel) DCB.
METHODS:This was a prospective, randomized, multicenter, single-blinded trial. Patients were randomized (3:1) to treatment with a low-dose DCB or an uncoated percutaneous transluminal angioplasty (PTA) balloon. The primary safety end point was a composite of freedom from device- and procedure-related death through 30 days after the procedure and freedom from target limb major amputation and clinically driven target lesion revascularization through 12 months after the procedure. The primary effectiveness end point was primary patency at 12 months.
RESULTS:Patients were randomized to treatment with a DCB (222 patients, 254 lesions) or uncoated PTA balloon (72 patients, 79 lesions) after successful predilatation. Mean lesion length was 7.2 and 7.1 cm, and 19.2% and 19.0% of lesions represented total occlusions, respectively. The primary safety end point was met, and superiority was demonstrated; freedom from a primary safety event was 94.1% (193 of 205) with DCB and 83.3% (50 of 60) with PTA, for a difference of 10.8% (95% confidence interval, 0.9%–23.0%). The primary effectiveness end point was met, and superiority of DCB over PTA was achieved (83.9% 188 of 224 versus 60.6% 40 of 66; P<0.001). Outcomes with DCB were also superior to PTA per the Kaplan-Meier estimate for primary patency (89.0% versus 65.0% at 365 days; log-rank P<0.001) and for rates of clinically driven target lesion revascularization (5.9% versus 16.7%; P=0.014).
CONCLUSIONS:Superiority with a low-dose DCB for femoropopliteal interventions was demonstrated over PTA for both the safety and effectiveness end points.
CLINICAL TRIAL REGISTRATION:URLhttp://www.clinicaltrials.gov. Unique identifierNCT01858363.
Artificial photosynthesis and the production of solar fuels could be a key element in a future renewable energy economy providing a solution to the energy storage problem in solar energy conversion. ...We describe a hybrid strategy for solar water splitting based on a dye sensitized photoelectrosynthesis cell. It uses a derivatized, core–shell nanostructured photoanode with the core a high surface area conductive metal oxide film––indium tin oxide or antimony tin oxide––coated with a thin outer shell of TiO ₂ formed by atomic layer deposition. A “chromophore–catalyst assembly” 1, (PO ₃H ₂) ₂bpy) ₂Ru(4-Mebpy-4-bimpy)Rub(tpy)(OH ₂) ⁴⁺, which combines both light absorber and water oxidation catalyst in a single molecule, was attached to the TiO ₂ shell. Visible photolysis of the resulting core–shell assembly structure with a Pt cathode resulted in water splitting into hydrogen and oxygen with an absorbed photon conversion efficiency of 4.4% at peak photocurrent.
Infectious disease modeling has played a prominent role in recent outbreaks, yet integrating these analyses into public health decision-making has been challenging. We recommend establishing ...‘outbreak science’ as an inter-disciplinary field to improve applied epidemic modeling.
We present the results of a binary population study in the Orion Nebula Cluster (ONC) using archival Hubble Space Telescope (HST) data obtained with the Advanced Camera for Surveys in Johnson V ...filter (HST Proposal 10246, PI M. Robberto). Young clusters and associations hold clues to the origin and properties of multiple star systems. Binaries with separations <100 au are useful as tracers of the initial binary population because they are not as likely to be destroyed through dynamical interactions. Low-mass, low stellar density, star-forming regions such as Taurus-Auriga, reveal an excess of multiples compared to the Galactic field. Studying the binary population of higher mass, higher stellar density star-forming regions like the ONC provides useful information concerning the origin of the Galactic field star population. In this survey, we characterize the previously unexplored (and incomplete) separation parameter space of binaries in the ONC (15-160 au) by fitting a double-point-spread function (PSF) model built from empirical PSFs. We identified 14 candidate binaries (11 new detections) and find that of our observed sample are in binary systems, complete over mass ratios and separations of 0.6 < q < 1.0 and 30 < a < 160 au. This is consistent with the Galactic field M-dwarf population over the same parameter ranges, 6.5% 3%. Therefore, high-mass star-forming regions like the ONC would not require further dynamical evolution for their binary population to resemble the Galactic field, as some models have hypothesized for young clusters.
The generation of large-scale biomedical data is creating unprecedented opportunities for basic and translational science. Typically, the data producers perform initial analyses, but it is very ...likely that the most informative methods may reside with other groups. Crowdsourcing the analysis of complex and massive data has emerged as a framework to find robust methodologies. When the crowdsourcing is done in the form of collaborative scientific competitions, known as Challenges, the validation of the methods is inherently addressed. Challenges also encourage open innovation, create collaborative communities to solve diverse and important biomedical problems, and foster the creation and dissemination of well-curated data repositories.
Abstract High-contrast imaging of debris disk systems permits us to assess the composition and size distribution of circumstellar dust, to probe recent dynamical histories, and to directly detect and ...characterize embedded exoplanets. Observations of these systems in the infrared beyond 2–3 μ m promise access to both extremely favorable planet contrasts and numerous scattered-light spectral features—but have typically been inhibited by the brightness of the sky at these wavelengths. We present coronagraphy of the AU Microscopii (AU Mic) system using JWST’s Near Infrared Camera (NIRCam) in two filters spanning 3–5 μ m. These data provide the first images of the system’s famous debris disk at these wavelengths and permit additional constraints on its properties and morphology. Conducting a deep search for companions in these data, we do not identify any compelling candidates. However, with sensitivity sufficient to recover planets as small as ∼0.1 Jupiter masses beyond ∼2″ (∼20 au) with 5 σ confidence, these data place significant constraints on any massive companions that might still remain at large separations and provide additional context for the compact, multiplanet system orbiting very close-in. The observations presented here highlight NIRCam’s unique capabilities for probing similar disks in this largely unexplored wavelength range, and they provide the deepest direct imaging constraints on wide-orbit giant planets in this very well-studied benchmark system.
The most widely studied mechanism of mass loss from extrasolar planets is photoevaporation via X-ray and ultraviolet ionization, primarily in the context of highly irradiated planets. However, the ...extreme ultraviolet dissociation of hydrogen molecules can also theoretically drive atmospheric evaporation on low-mass planets. For temperate planets such as the early Earth, impact erosion is expected to dominate in the traditional planetesimal accretion model, but it would be greatly reduced in pebble accretion scenarios, allowing other mass-loss processes to be major contributors. We apply the same prescription for photoionization to this photodissociation mechanism and compare it to an analysis of other possible sources of mass loss in pebble accretion scenarios. We find that there is no clear path to evaporating the primordial atmosphere accreted by an early Earth analog in a pebble accretion scenario. Impact erosion could remove ∼2300 bars of hydrogen if 1% of the planet's mass is accreted as planetesimals, while the combined photoevaporation processes could evaporate ∼750 bars of hydrogen. Photodissociation is likely a subdominant but significant component of mass loss. Similar results apply to super-Earths and mini-Neptunes. This mechanism could also preferentially remove hydrogen from a planet's primordial atmosphere, thereby leaving a larger abundance of primordial water compared to standard dry formation models. We discuss the implications of these results for models of rocky planet formation, including Earth's formation, and the possible application of this analysis to mass loss from observed exoplanets.
We present a statistical comparison of the mass ratio distribution of companions, as observed in different multiplicity surveys, to the most recent estimate of the single-object mass function. The ...main goal of our analysis is to test whether or not the observed companion mass ratio distribution (CMRD) as a function of primary star mass and star formation environment is consistent with having been drawn from the field star initial mass function (IMF). We consider samples of companions for M dwarfs, solar-type stars, and intermediate-mass stars, both in the field as well as clusters or associations, and compare them with populations of binaries generated by random pairing from the assumed IMF for a fixed primary mass. With regard to the field we can reject the hypothesis that the CMRD was drawn from the IMF for different primary mass ranges: the observed CMRDs show a larger number of equal-mass systems than predicted by the IMF. This is in agreement with fragmentation theories of binary formation. For the open clusters Delta *a Persei and the Pleiades we also reject the IMF random-pairing hypothesis. Concerning young star-forming regions, currently we can rule out a connection between the CMRD and the field IMF in Taurus but not in Chamaeleon I. Larger and different samples are needed to better constrain the result as a function of the environment. We also consider other companion mass functions and we compare them with observations. Moreover the CMRD both in the field and clusters or associations appears to be independent of separation in the range covered by the observations. Combining therefore the CMRDs of M (1-2400 AU) and G (28-1590 AU) primaries in the field and intermediate-mass primary binaries in Sco OB2 (29-1612 AU) for mass ratios, q = M 2/M 1, from 0.2 to 1, we find that the best chi-square fit follows a power law dN/dqq Delta *b, with Delta *b = --0.50 ? 0.29, consistent with previous results. Finally, we note that the Kolmogorov-Smirnov test gives a ~1% probability of the observed CMRD in the Pleiades and Taurus being consistent with that observed for solar-type primaries in the field over comparable primary mass range. This highlights the value of using CMRDs to understand which star formation events contribute most to the field.
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