We report the experimental observation of radiative recombination from Rydberg excitons in a two-dimensional semiconductor, monolayer WSe2, encapsulated in hexagonal boron nitride. Excitonic emission ...up to the 4s excited state is directly observed in photoluminescence spectroscopy in an out-of-plane magnetic field up to 31 T. We confirm the progressively larger exciton size for higher energy excited states through diamagnetic shift measurements. This also enables us to estimate the 1s exciton binding energy to be about 170 meV, which is significantly smaller than most previous reports. The Zeeman shift of the 1s to 3s states, from both luminescence and absorption measurements, exhibits a monotonic increase of the g-factor, reflecting nontrivial magnetic-dipole-moment differences between ground and excited exciton states. This systematic evolution of magnetic dipole moments is theoretically explained from the spreading of the Rydberg states in momentum space.
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IJS, KILJ, NUK, PNG, UL, UM
A search for sub-GeV dark matter produced from collisions of the Fermilab 8 GeV Booster protons with a steel beam dump was performed by the MiniBooNE-DM Collaboration using data from 1.86 × 1020 ...protons on target in a dedicated run. The MiniBooNE detector, consisting of 818 tons of mineral oil and located 490 meters downstream of the beam dump, is sensitive to a variety of dark matter initiated scattering reactions. Three dark matter interactions are considered for this analysis: elastic scattering off nucleons, inelastic neutral pion production, and elastic scattering off electrons. Multiple data sets were used to constrain flux and systematic errors, and time-of-flight information was employed to increase sensitivity to higher dark matter masses. No excess from the background predictions was observed, and 90% confidence level limits were set on the vector portal and leptophobic dark matter models. New parameter space is excluded in the vector portal dark matter model with a dark matter mass between 5 and 50 MeV c−2 . The reduced neutrino flux allowed to test if the MiniBooNE neutrino excess scales with the production of neutrinos. No excess of neutrino oscillation events were measured ruling out models that scale solely by number of protons on target independent of beam configuration at 4.6σ.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Human ear morphology, a complex anatomical structure represented by a multidimensional set of correlated and heritable phenotypes, has a poorly understood genetic architecture. In this study, we ...quantitatively assessed 136 ear morphology traits using deep learning analysis of digital face images in 14,921 individuals from five different cohorts in Europe, Asia, and Latin America. Through GWAS meta-analysis and C-GWASs, a recently introduced method to effectively combine GWASs of many traits, we identified 16 genetic loci involved in various ear phenotypes, eight of which have not been previously associated with human ear features. Our findings suggest that ear morphology shares genetic determinants with other surface ectoderm-derived traits such as facial variation, mono eyebrow, and male pattern baldness. Our results enhance the genetic understanding of human ear morphology and shed light on the shared genetic contributors of different surface ectoderm-derived phenotypes. Additionally, gene editing experiments in mice have demonstrated that knocking out the newly ear-associated gene (Intu) and a previously ear-associated gene (Tbx15) causes deviating mouse ear morphology.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The space hurricane is a large‐scale three‐dimensional magnetic vortex structure that can cause massive local energy injections in the polar cap. By analyzing Defense Meteorological Satellite Program ...(DMSP) F16–F19 satellite observations from 2005 to 2016, we found that the Southern Hemisphere space hurricane mainly occurs in summer under negative By dominated northward interplanetary magnetic field (IMF) conditions. In particular, the space hurricanes are more likely to occur in the dayside polar cap at magnetic latitude greater than 80°. The characteristics for the Southern Hemisphere are basically consistent with the characteristics of space hurricanes in the Northern Hemisphere. The different dependences of By component in different hemispheres supports the high‐latitude lobe reconnection as the formation mechanism. Plasma data from DMSP satellites in both hemispheres show that the appearance of the space hurricane greatly enhances the convection in the polar cap and the electron density on its dawn side. Within the space hurricane, electron temperatures typically increase significantly, accompanied by strong upward field‐aligned currents and electron precipitation. These results give us a better understanding of the solar wind‐magnetosphere‐polar ionosphere coupling process under northward IMF conditions.
Plain Language Summary
The space hurricane is defined as a large three‐dimensional magnetic vortex structure that spans the polar ionosphere and magnetosphere. Previous research has pointed out that it often appears as an aurora spot near the north magnetic pole, which can greatly enhance the convection patterns and current systems in the polar ionosphere. To clarify its occurrence rate and characteristics in the Southern Hemisphere, we identified the 259 space hurricane events from the long‐term DMSP satellite observations in the Southern Hemisphere. The statistical results indicated that the Southern Hemisphere space hurricanes mainly occur in summer and dayside polar cap under negative By dominated and northward IMF conditions. In addition, we found that the electron temperatures within the space hurricane increased significantly and accompanied by strong upward field‐aligned field currents and electron precipitation. The appearance of the space hurricane greatly enhances the plasma velocity and the electron density on its dawn side. The characteristics in the Southern Hemisphere are basically consistent with the characteristics of space hurricanes in the Northern Hemisphere, and support high‐latitude lobe reconnection as the formation mechanism. This work helps us understand the spatial and temporal characteristics of the space hurricane and their impact on plasma parameters.
Key Points
Space hurricanes in the Southern Hemisphere mainly occur in summer and afternoon sector with negative By dominated northward IMF
Plasma data from DMSP satellites indicate that the space hurricane has enhanced Te, horizontal convection and Ne on its dawn side
Statistical properties of space hurricanes in the Southern Hemisphere are consistent with high‐latitude lobe reconnection
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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The regulatory protein encoded by the
rosR
gene is involved in the processes of adaptation of root nodule bacteria
Rhizobium leguminosarum
to changes in environmental conditions. It affects the ...expression of a number of genes associated with the synthesis of exopolysaccharides, which play a critical role in formation of bacterial biofilms on various surfaces. The goal of this work was to study the effect of overexpression of the
rosR
gene on formation of
R. leguminosarum
biofilms on inert surfaces and roots of heterologous plant hosts by obtaining recombinant strains with an additional copy of the
rosR
gene under the control of the Pm promoter. Our analysis of recombinant strains showed that additional expressed copies of the
rosR
gene allowed rhizobia to overcome the inhibitory effect on biofilm formation caused by low calcium concentrations in the medium, the effect of proteases and detergents, and to form biofilms more efficiently on the surface of tomato and clover roots. The results obtained open up prospects for using
rosR
as a tool both for increasing the efficiency of endosymbiosis of rhizobia with legumes, and for the formation of stable associative interactions with other agricultural crops.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Studies have shown that rates of liver disease are higher in persons who are coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) than they are in persons with HCV alone, ...but estimates of risk vary widely and are based on data for dissimilar patient populations. We performed a meta-analysis to quantify the effect of HIV coinfection on progressive liver disease in persons with HCV. Eight studies were identified that included outcomes of histological cirrhosis or decompensated liver disease. These studies yielded a combined adjusted relative risk (RR) of 2.92 (95% confidence interval CI, 1.70-5.01). Of note, studies that examined decompensated liver disease had a combined RR of 6.14 (95% CI, 2.86-13.20), whereas studies that examined histological cirrhosis had a pooled RR of 2.07 (95% CI, 1.40-3.07). There is a significantly elevated RR of severe liver disease in persons who are coinfected with HIV and HCV. This has important implications for timely diagnosis and consideration of treatment in coinfected persons.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Dumbbell-like Au−Fe3O4 nanoparticles are synthesized using decomposition of Fe(CO)5 on the surface of the Au nanoparticles followed by oxidation in 1-octadecene solvent. The size of the particles is ...tuned from 2 to 8 nm for Au and 4 nm to 20 nm for Fe3O4. The particles show the characteristic surface plasmon absorption of Au and the magnetic properties of Fe3O4 that are affected by the interactions between Au and Fe3O4. The dumbbell is formed through epitaxial growth of iron oxide on the Au seeds, and the growth can be affected by the polarity of the solvent, as the use of diphenyl ether results in flower-like Au−Fe3O4 nanoparticles.
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IJS, KILJ, NUK, PNG, UL, UM
Results from epidemiologic studies examining pancreatic cancer risk and vitamin D intake or 25-hydroxyvitamin D (25(OH)D) concentrations (the best indicator of vitamin D derived from diet and sun) ...have been inconsistent. Therefore, the authors conducted a pooled nested case-control study of participants from 8 cohorts within the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers (VDPP) (1974-2006) to evaluate whether prediagnostic circulating 25(OH)D concentrations were associated with the development of pancreatic cancer. In total, 952 incident pancreatic adenocarcinoma cases occurred among participants (median follow-up, 6.5 years). Controls (n = 1,333) were matched to each case by cohort, age, sex, race/ethnicity, date of blood draw, and follow-up time. Conditional logistic regression analysis was used to calculate smoking-, body mass index-, and diabetes-adjusted odds ratios and 95% confidence intervals for pancreatic cancer. Clinically relevant 25(OH)D cutpoints were compared with a referent category of 50-<75 nmol/L. No significant associations were observed for participants with lower 25(OH)D status. However, a high 25(OH)D concentration (> or =100 nmol/L) was associated with a statistically significant 2-fold increase in pancreatic cancer risk overall (odds ratio = 2.12, 95% confidence interval: 1.23, 3.64). Given this result, recommendations to increase vitamin D concentrations in healthy persons for the prevention of cancer should be carefully considered.
We developed an enantioselective voltammetric sensor based on a carbon-paste electrode modified by enantiomorphic crystals of bromotriphenylmethane for the recognition and determination of tryptophan ...enantiomers. Enantiomorphic crystals of bromotriphenylmethane were obtained under the condition of Viedma ripening. The electrochemical and analytical characteristics of the sensor were studied. The proposed sensor was used to recognize and determine the enantiomers of L- and D-tryptophan in model solutions of pharmaceutical preparations and in human urine and blood plasma samples. The sensor is easy to manufacture and exhibits high reproducibility and stability. It was shown that, in using chemometric data processing, the presence of even slight differences between the voltammograms of enantiomers recorded using the proposed carbon-paste electrode is sufficient for their reliable recognition.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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