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COVID-19 caused by SARS-CoV-2 is a worldwide problem. From the standpoint of hospital infection control, determining the source of infection is critical. We conducted the present study to evaluate the efficacy of using whole genome sequencing to determine the source of infection in hospitalized patients who do not have a clear infectious contact history. Recently, we encountered two seemingly separate COVID-19 clusters in a tertiary hospital. Whole viral genome sequencing distinguished the two clusters according to the viral haplotype. However, the source of infection was unclear in 14 patients with COVID-19 who were clinically unlinked to clusters #1 or #2. These patients, who had no clear history of infectious contact within the hospital ("undetermined source of infection"), had haplotypes similar to those in cluster #2 but did not have two of the mutations used to characterize cluster #2, suggesting that these 14 cases of "undetermined source of infection" were not derived from cluster #2. Whole viral genome sequencing can be useful for confirming that sporadic COVID-19 cases with an undetermined source of infection are indeed not part of clusters at the institutional level. [ABSTRACT FROM AUTHOR]

Abstract: Granitic rocks are commonly used as means to study chemical evolution of continental crust, particularly, their isotopic compositions, which reflect the relative contributions of mantle and crustal components in their genesis. New SIMS and K–Ar geochronology, isotope, geochemical, and mineral chemistry data are presented for the granitoid rocks located in and around Gabal Dara in the Northern Eastern Desert of Egypt. The granitoid suite comprises quartz diorites, Muscovite (Mus) trondhjemites, and granodiorites intruded by biotite-hornblende (BH) granites and alkali feldspar (AF) granites. Mus trondhjemite, granodiorite and BH granite exhibit I-type calc alkaline affinities. Mus trondhjemite and granodiorite show medium-K calc-alkaline and metaluminous/mildy peraluminous affinities, whereas BH granites have high-K calc-alkaline and metaluminous character. Concordant 206Pb/238U weighted mean ages together with geochemical peculiarities suggest that Mus trondhjemites (741Ma) followed by granodiorites (720Ma) are genetically unrelated, and formed in subduction-related regime by partial melting of lower oceanic crust together with a significant proportion of mantle melt. The genesis of Mus trondhjemites is correlated with the main event in the evolution of the Eastern Desert, called “~750Ma crust forming event”. The field and geochemical criteria together with age data assign the high-K calc-alkaline BH granites (608–590Ma) and alkaline AF granites (600–592Ma) as post-collisional granites. The differences in geochemical traits, e.g. high-K calc-alkaline versus alkaline/peralkaline affinities respectively, suggest that BH granites and AF granites are genetically unrelated. The age overlap indicating coeval generation of calc-alkaline and alkaline melts, which in turn suggests that magma genesis was controlled by local composition of the source. The high-K calc-alkaline BH granites are most likely generated from lithospheric mantle melt which have been hybridized by crustal melts produced by underplating process. AF granites exhibit enrichment in K2O, Rb, Nb, Y, and Th, and depletion in Al2O3, TiO2, MgO, CaO, FeO, P2O5, Sr, and Ba as well as alkaline/peralkaline affinity. These geochemical criteria combined with the moderately fractionated rare earth elements pattern (LaN/YbN =9–14) suggest that AF granite magma might have been generated by partial melting of Arabian–Nubian Shield (ANS) arc crust in response of upwelling of hot asthenospheric mantle melts, which became in direct contact with lower ANS continental crust material due to delamination. Furthermore, a minor role of crystal fractionation of plagioclase, amphibole, biotite, zircon, and titanomagnetite in the evolution of AF granites is also suggested. The low initial 87Sr/86Sr ratios (0.7033–0.7037) and positive εNd (T) values (+2.32 to +4.71) clearly reflect a significant involvement of depleted mantle source in the generation of the post-collision granites and a juvenile nature for the ANS. [Copyright &y& Elsevier]

A 47-year-old woman with dysphagia and ptosis gradually developed dysarthria and muscular weakness. Magnetic resonance imaging, testing for anti-acetylcholine receptor antibodies, edrophonium chloride (EC) test, and electrophysiologic test revealed no abnormalities. A psychogenic reaction was suspected. Four months after disease onset, the patient presented to our hospital. In videofluoroscopic examination of swallowing (VF), there was no aspiration for swallowing of either liquid or soft food. It revealed, however, poor pharyngeal constriction, no epiglottis inversion, repeated swallowing movements, and large amounts of pharyngeal residue. Videofluoroscopic examination of swallowing after an intravenous injection of 10 mg EC showed improvements in all above observations; particularly, it was clear when swallowing soft food. Furthermore, the anti-muscle-specific kinase (MuSK) antibody titer was elevated, and anti-MuSK antibody-positive myasthenia gravis (MuSK-MG) was diagnosed. Thus VF during EC test may be helpful in diagnosing MuSK-MG in patients with dysphagia. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the fabrication of single-phase Nb films and hetero-epitaxial multi-layered films of Nb/AlN/Nb for SIS junctions. The Nb and multi-layered Nb/AlN/Nb films were deposited on NbN buffered MgO(100) single-crystal substrates at 753K by using a dc magnetron sputtering system. We observed that the Nb films grow to Nb(200) orientation by measuring a standard 2θ/θ X-ray diffraction. The φ-scan diffraction peaks of Nb(200) were rotated by 45 degrees in-plane orientation for those of both NbN(220) and MgO(220). We found that NbN buffer layer with the thickness of a few nm was effective to enhance the Nb(200) orientation. The best thickness for a NbN buffer layer to grow epitaxial of Nb film was approximately 3nm. Also, we examined dependence of degree of Nb(200) orientation and surface roughness(Ra) on multi-layered films. As a result, we found that the multi-layered films had flat surface interfaces for SIS junctions almost equivalent to single-layered films. [Copyright &y& Elsevier]