The outbreak of COVID-19 poses unprecedent challenges to global health 1 . The new coronavirus, SARS-CoV-2, shares high sequence identity to SARS-CoV and a bat coronavirus RaTG13 2 . While bats may be the reservoir host for various coronaviruses 3,4 , whether SARS-CoV-2 has other hosts remains ambiguous. In this study, one coronavirus isolated from a Malayan pangolin showed 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S genes, respectively. In particular, the receptor-binding domain within the S protein of the Pangolin-CoV is virtually identical to that of SARS-CoV-2, with one noncritical amino acid difference. Results of comparative genomic analysis suggest that SARS-CoV-2 might have originated from the recombination of a Pangolin-CoV-like virus with a Bat-CoV-RaTG13-like virus. The Pangolin-CoV was detected in 17 of 25 Malayan pangolins analyzed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against Pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus that is highly related to SARS-CoV-2 in pangolins suggests that they have the potential to act as the intermediate host of SARS-CoV-2. The newly identified coronavirus in the most-trafficked mammal could represent a future threat to public health if wildlife trade is not effectively controlled.As coronaviruses (CoVs) are common in mammals and birds 5 , we used the whole genome sequence of SARS-CoV-2 (WHCV; GenBank accession No. MN908947) in a Blast search of SARS-relate CoV (SARSr-CoV) sequences in available mammalian and avian viromic, metagenomic, and transcriptomic data. This led to the identification of 34 highly related contigs in a set of pangolin viral metagenomes (Extended

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The topological three-dimensional Dirac semimetal Cd3As2 has drawn great attention for the novel physics and promising applications in optoelectronic devices operating in the infrared and THz regimes. Among the extensive studies in the past

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Lateral patch-clamping has emerged as a chip-based platform for automation of the conventional patch-clamp technique, the 'gold' standard for studying cellular ion channels. The conventional technique, as it relies on skilled-maneuver of glass micropipettes to patch cells, is extremely delicate, low in throughput, and thus cannot be used for primary screening of compounds against ion channels. Direct integration of glass capillaries on silicon provides lateral junctions for automated trapping and patching of cells. We demonstrate here a method of scaling up the lateral junctions to a standard 1536-well microtiter plate format. A single unit of 1536-well plate has been formed here on a 9 mm by 9 mm microstructured silicon with the inclusive of 16 wells molded in a capping layer made of polydimethylsiloxane (PDMS). The silicon substrate provides integrated glass capillaries (total 12) and their associated microfluidic network. Each glass capillary has an independent access through a dedicated well in PDMS and leads to a centralized channel in which cell suspension can be delivered through one of the remaining 4 wells. The unit has been tested on RBL-1 cells by recording whole-cell activity from inwardly rectifying endogenous potassium channels. A revised test protocol has been prescribed to avoid inaccurate readings due to altered ionic composition of the recording buffer when a typical suction is applied to capture cells.

The atomically thin layered transition metal dichalcogenide (TMDCs) PtSe2 is a new emerging two-dimension (2D) material, which has a transition from indirect-gap semiconductor to semimetal with increasing thickness. Defects in 2D TMDCs are very ubiquitous and play a crucial role in understanding many electronics and optoelectronics in TMDCs. In this article, PtSe2 films with different thickness are obtained by selenizing the variously thick Pt films. Extrapolation of the onset absorption from the visible-infrared spectrum demonstrates that the selenization of 1 and 3 nm Pt films shows semiconductor-like character, while those of thick Pt films (with thickness of 10 and 15 nm) show metallic behavior. The transient absorption (TA) spectroscopy reveals that all films show immediately photobleaching signals after photoexcitation at 800 nm, and the subsequent relaxation process shows strongly thickness dependence. The thinnest film shows biexponential relaxation with typical time constants of 1.28 and 101.2 ps. In contrast, the photobleaching signals are developed into photoinduced absorption signals in thicker films, and the absorption magnitude increases with the thickness of the films. The optical pump and terahertz (THz) probe spectroscopy reveals that all samples show positive photoconductivity after photoexcitation of 800 nm, the subsequent recovery is completed within 2.0 ps, and the recovery time constant decreases with the increase of the films’ thickness. Our TA and THz spectroscopy results reveal that the defect states of the films play dominated role in the relaxation of photocarrier after photoexcitation, and edge-site states are inferred to make dominated contributions to the defect states in the selenization of platinum films.

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Diffuse sclerosing papillary thyroid carcinoma (DSPTC) is a relatively rare variant of papillary thyroid carcinoma with distinct histological features, radiological characteristics, and biological aggressiveness. Compared with conventional papillary thyroid carcinoma, DSPTC is characterized by scattered microscopic tumor islands, diffuse fibrosis, calcification, and abundant lymphocytic aggregation. A preoperative diagnosis is challenging in the absence of nodules and scanty fine needle aspiration cytology samples. We describe a unique DSPTC patient, an 18-year-old woman who presented with a neck mass that grew slowly for 2 years. The palpable neck mass was nontender, well defined, firm, and unmovable. Laboratory studies showed normal thyroid function and positive autoimmune markers: antithyroglobulin antibody = 1:1600 and antimicrosomal antibody = 1:1600. A neck ultrasound showed diffusely prominent microcalcifications with one small vague nodule. Hashimoto's thyroiditis with an accompanying malignancy was suspected. Based on the result of intraoperative pathology reports, the patient was given a total thyroidectomy. Lymph node dissection and histological analysis revealed bilateral DSPTC in addition to lymphocytic thyroiditis in nonmalignant areas of the thyroid. Clinical and histological diagnostic challenges usually occur when DSPTC presents with a diffuse thyroid enlargement, dispersed microscopic tumor islands (frequently without mass formation), extensive fibrosis, and abundant lymphocytic infiltration mimicking thyroiditis.