Coronavirus disease 2019 (COVID-19) represents a global crisis, yet major knowledge gaps remain about human immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We analyzed ...immune responses in 76 COVID-19 patients and 69 healthy individuals from Hong Kong and Atlanta, Georgia, United States. In the peripheral blood mononuclear cells (PBMCs) of COVID-19 patients, we observed reduced expression of human leukocyte antigen class DR (HLA-DR) and proinflammatory cytokines by myeloid cells as well as impaired mammalian target of rapamycin (mTOR) signaling and interferon-α (IFN-α) production by plasmacytoid dendritic cells. By contrast, we detected enhanced plasma levels of inflammatory mediators-including EN-RAGE, TNFSF14, and oncostatin M-which correlated with disease severity and increased bacterial products in plasma. Single-cell transcriptomics revealed a lack of type I IFNs, reduced HLA-DR in the myeloid cells of patients with severe COVID-19, and transient expression of IFN-stimulated genes. This was consistent with bulk PBMC transcriptomics and transient, low IFN-α levels in plasma during infection. These results reveal mechanisms and potential therapeutic targets for COVID-19.
For decades, dental schools in the United States have endured a significant faculty shortage. Studies have determined that the top 2 sources of dental faculty are advanced education programs and ...private practice. Those who have completed both DDS and PhD training are considered prime candidates for dental faculty positions. However, there is no national database to track those trainees and no evidence to indicate that they entered academia upon graduation. The objective of this study was to assess outcomes of dental school–affiliated oral sciences PhD program enrollment, graduates, and placement between 1994 and 2016. Using the American Dental Association annual survey of advanced dental education programs not accredited by the Commission on Dental Accreditation and data obtained from 22 oral sciences PhD programs, we assessed student demographics, enrollment, graduation, and placement. Based on the data provided by program directors, the average new enrollment was 33, and graduation was 26 per year. A total of 605 graduated; 39 did not complete; and 168 were still in training. Among those 605 graduates, 211 were faculty in U.S. academic institutions, and 77 were faculty in foreign institutions. Given that vacant budgeted full-time faculty positions averaged 257 per year during this period, graduates from those oral sciences PhD programs who entered academia in the United States would have filled 9 (3.6%) vacant faculty positions per year. Therefore, PhD programs have consistently generated only a small pipeline of dental school faculty. Better mentoring to retain talent in academia is necessary. Stronger support and creative funding plans are essential to sustain the PhD program. Furthermore, the oral sciences PhD program database should be established and maintained by dental professional organizations to allow assessments of training models, trends of enrollment, graduation, and placement outcomes.
In this paper we present the Low Frequency Instrument (LFI), designed and developed as part of the Planck space mission, the ESA programme dedicated to precision imaging of the cosmic microwave ...background (CMB). Planck-LFI will observe the full sky in intensity and polarisation in three frequency bands centred at 30, 44 and 70 GHz, while higher frequencies (100–850 GHz) will be covered by the HFI instrument. The LFI is an array of microwave radiometers based on state-of-the-art indium phosphide cryogenic HEMT amplifiers implemented in a differential system using blackbody loads as reference signals. The front end is cooled to 20 K for optimal sensitivity and the reference loads are cooled to 4 K to minimise low-frequency noise. We provide an overview of the LFI, discuss the leading scientific requirements, and describe the design solutions adopted for the various hardware subsystems. The main drivers of the radiometric, optical, and thermal design are discussed, including the stringent requirements on sensitivity, stability, and rejection of systematic effects. Further details on the key instrument units and the results of ground calibration are provided in a set of companion papers.
Summary
House design may affect an individual's exposure to malaria parasites, and hence to disease. We conducted a randomized‐controlled study using experimental huts in rural Gambia, to determine ...whether installing a ceiling or closing the eaves could protect people from malaria mosquitoes. Five treatments were tested against a control hut: plywood ceiling; synthetic‐netting ceiling; insecticide‐treated synthetic‐netting ceiling (deltamethrin 12.5 mg/m2); plastic insect‐screen ceiling; or the eaves closed with mud. The acceptability of such interventions was investigated by discussions with local communities. House entry by Anopheles gambiae, the principal African malaria vector, was reduced by the presence of a ceiling: plywood (59% reduction), synthetic‐netting (79%), insecticide‐treated synthetic‐netting (78%), plastic insect‐screen (80%, P < 0.001 in all cases) and closed eaves (37%, ns). Similar reductions were also seen with Mansonia spp., vectors of lymphatic filariasis and numerous arboviruses. Netting and insect‐screen ceilings probably work as decoy traps attracting mosquitoes into the roof space, but not the room. Ceilings are likely to be well accepted and may be of greatest benefit in areas of low to moderate transmission and when used in combination with other malaria control strategies.
A field experiment was conducted in northern Chile at an altitude of 5.3 km to evaluate the accuracy of line‐by‐line radiative transfer models in regions of the spectrum that are typically opaque at ...sea level due to strong water vapor absorption. A suite of spectrally resolved radiance instruments collected simultaneous observations that, for the first time ever, spanned the entire terrestrial thermal spectrum (i.e., from 10 to 3000 cm−1, or 1000 to 3.3 μm). These radiance observations, together with collocated water vapor and temperature profiles, are used to provide an initial evaluation of the accuracy of water vapor absorption in the far‐infrared of two line‐by‐line radiative transfer models. These initial results suggest that the more recent of the two models is more accurate in the strongly absorbing water vapor pure rotation band. This result supports the validity of the Turner et al. (2012) study that demonstrated that the use of the more recent water vapor absorption model in climate simulations resulted in significant radiative and dynamical changes in the simulation relative to the older water vapor model.
Key PointsFirst ground‐based spectrally‐resolved observations of entire infrared spectrumExtremely dry conditions result in semi‐transparent regions in far‐infraredObservations used to evaluate line‐by‐line radiative transfer models
The monarch butterfly,
Danaus plexippus
L. (Lepidoptera: Nymphalidae), is found across North America during the summer months. Adult populations from western North America migrate to roost along the ...central coast of California. Monarchs that disperse in the spring to the arid regions of southern California encounter widely dispersed individuals of desert milkweed species, including
Asclepias fascicularis
Decne. (Narrow-Leaf Milkweed),
A. californica
E. Greene (California Milkweed),
A. eriocarpa
Benth. (Indian Milkweed), and
A. erosa
Torrey (Desert Milkweed). The four species represent a range in suitability as hosts for monarch larvae. In laboratory assays of plants grown from wild-collected seeds, neonate larvae showed the least preference for
A. fascicularis
in host-selection assays and there were no differences in preference among the other three species. Previous research has shown that
A. fascicularis
has the lowest level of cardiac glycosides and the lowest latex flow of the four species examined. The leaf hairs of
A. californica
and
A. eriocarpa
provide a significant barrier to neonate larval success; larvae feeding on shaved leaves were significantly larger than larvae feeding on leaves with intact hairs. First instar larval behavior of cutting hairs before beginning to feed may improve their success by modifying plant quality and defenses.
The first wave of pandemic influenza A(H1N1) has subsided in New Zealand as in other southern hemisphere countries. This study aimed to estimate the effective reproduction number (R) of 2009 pandemic ...influenza A(H1N1) taking into account imported cases. It also aimed to show the temporal variation of R throughout the New Zealand epidemic, changes in age- and ethnicity-specific cumulative incidence, and the effect of school holidays. Using a new modelling method to account for imported cases, we have calculated the peak R during the containment phase of the pandemic as 1.55 (95% confidence interval: 1.16 to 1.86). This value is less than previously estimated in the country early in the pandemic but in line with more recent estimates in other parts of the world. Results also indicated an increase in the proportion of notifications among school-age children after the school holiday (3-19 July 2009). This finding provides support for the potential effectiveness of timely school closures, although such disruptive interventions need to be balanced against the severity of the pandemic.
Background
Patients with multiple sclerosis (MS) are more frequently born in spring when compared to autumn. Fluctuation of UV‐light has been hypothesized to drive this phenomenon.
Aim
To assess the ...correlation between fluctuation of sunlight and birth season in persons with MS.
Methods
For this record‐linkage study, we collected from the international MSBase and the Italian MS iMed‐web databases the dates of birth of 11,415 patients with MS from 36 centres from 15 countries worldwide and compared these to dates of live‐births from national registries. From all participating sites, we collected data on UV‐light fluctuation and assessed its correlation with seasonal fluctuation in MS births.
Results
Compared with the reference cohort, an increased proportion of persons with MS were born in spring and a decreased proportion in autumn (odds ratio (OR) to be born in spring versus autumn = 1.158, χ2 = 36.347, P < 0.001). There was no significantly increased fluctuation of MS births with increased quartile of ambient UV‐light fluctuation (Ptrend = 0.086).
Conclusion
Seasonal fluctuation of MS births as found in this worldwide cohort of patients with MS did not correlate with variation in seasonal fluctuation of UV‐light. Most likely, it results from a complex interplay between fluctuation of sunlight, behavioural factors, other environmental factors and (epi)genetic factors.
Uranium(VI) alkoxide complexes are prepared via metathesis reactions of UO2Cl2(THF)22 with potassium alkoxides in nonaqueous media. The dark red compound UOCH2C(CH3)36, 1, results from redistributive ...exchange of oxo and neopentoxide ligands between more than one uranium species. Single-crystal X-ray diffraction analysis of 1 reveals a monomer in which the uranium is coordinated in a pseudooctahedral fashion by six neopentoxide ligands. Imposition of steric congestion at the metal center prevents oxo−alkoxide ligand exchange in the reactions using more sterically demanding alkoxides. Simple metathesis between uranyl chloride and alkoxide ligands occurs in the synthesis of golden yellow-orange UO2(OCHPh2)2(THF)2, 2, and yellow UO2OCH( t Bu)Ph2(THF)2, 3. Single-crystal X-ray diffraction analysis of 2 reveals a monomer in which the uranium is coordinated in a pseudooctahedral fashion by two apical oxo ligands, two diphenylmethoxide ligands occupying trans positions, and two tetrahydrofuran ligands. Coordination of diisopropylmethoxide allows for synthesis of a more complex binary alkoxide system. Single-crystal X-ray diffraction analysis of watermelon red UO2(OCH( i Pr)2)24, 4, reveals a tetramer in which each uranium is coordinated in a pseudooctahedral fashion by two apical oxo ligands, one terminal alkoxide, two bridging alkoxide ligands, and one bridging oxo ligand from a neighboring uranyl group. These compounds are characterized by elemental analysis, 1H NMR, infrared spectroscopy, and, for 1, 2, and 4, single-crystal X-ray diffraction analysis. Luminescence spectroscopy is employed to evaluate the extent of aggregation of compounds 2−4 in various solvents. Vibrational spectroscopic measurements of 2−4 imply that, in contrast to the case of uranyl complexes prepared in aqueous environments, coordination of relatively strongly donating alkoxide ligands allows for enhancement of electron density on the uranyl groups such that the uranyl UO bonds are weakened. Crystal data are as follows. 1: monoclinic space group C2/m, a = 10.6192(8) Å, b = 18.36(1) Å, c = 10.6151(8) Å, β = 109.637(1)°, V = 1949.1(3) Å3, Z = 2, d calc = 1.297 g cm-3. Refinement of 2065 reflections gave R1 = 0.045. 2: monoclinic space group P21/c, a = 6.1796(4) Å, b = 15.669(1) Å, c = 16.169(1) Å, β = 95.380(1)°, V = 1558.7(2) Å3, Z = 2, d calc = 1.664 g cm-3. Refinement of 3048 reflections gave R1 = 0.036. 4: tetragonal space group I4̄, a = 17.8570(6) Å, b = 17.8570(6) Å, c = 11.4489(6) Å, V = 3650.7(3) Å3, Z = 2, d calc = 1.821 g cm-3. Refinement of 1981 reflections gave R1 = 0.020.
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