Electrical Switching of the Edge Current Chirality in Quantum Anomalous Hall Insulators

A quantum anomalous Hall (QAH) insulator is a topological state of matter, in which the interior is insulating but electrical current flows along the edges of the sample, in either clockwise (right-handed) or counter-clockwise (left-handed) direction dictated by the spontaneous magnetization orientation. Such chiral edge current (CEC) eliminates any backscattering, giving rise to quantized Hall resistance and zero longitudinal resistance. In this work, we fabricate mesoscopic QAH sandwich (i.e. magnetic topological insulator (TI)/TI/magnetic TI) Hall bar devices and succeed in switching the CEC chirality in QAH insulators through spin-orbit torque (SOT) by applying a current pulse and suitably controlled gate voltage. The well-quantized QAH states with opposite CEC chiralities are demonstrated through four- and three-terminal measurements before and after SOT switching. Our theoretical calculations show that the SOT that enables the magnetization switching can be generated by both bulk and surface carriers in QAH insulators, in good agreement with experimental observations. Current pulse-induced switching of the CEC chirality in QAH insulators will not only advance our knowledge in the interplay between magnetism and topological states but also expedite easy and instantaneous manipulation of the QAH state in proof-of-concept energy-efficient electronic and spintronic devices as well as quantum information applications.Comment: 24 pages, 5 figures, comments are welcom

Going deeper and further: a range and depth extension for the deep-sea feather star Paratelecrinus cubensis (Carpenter, 1881) (Comatulida, Atelecrinidae), first record from the Western Pacific

A specimen belonging to the deep-sea feather-star family Atelecrinidae was collected in April 2018 at the Kocebu Guyot at 1294 m deep. Based on its morphological characters, the specimen was identified as Paratelecrinus cubensis (Carpenter, 1881). This species of feather star is restricted to the deep sea and was known only from 12 records from the Bahamas and Cuba at depths of 567–892 m. The data represent the first record from the Western Pacific Ocean and the deepest record known, extending the depth where this feather star has been found to beyond 1000 m. The morphological characteristics of the Kocebu Guyot specimen were essentially identical to the morphology of the neotype, with a slight difference in the dorsal spine at the end of the cirri. The phylogenetic analysis based on the mitochondrial cytochrome c oxidase subunit I (COI), 16S rRNA genes, 28S rRNA genes, and 18S rRNA genes reveal a close relationship of P. cubensis with P. wyvilli. Results of our molecular phylogenetic analysis are consistent with our morphological identifications. Our find extends the known geographical distribution of the feather star P. cubensis to the Western Pacific Ocean and provide insights into deep-sea biodiversity in the Kocebu Guyot

Paratelecrinus Messing 2013

<p>Genus Paratelecrinus Messing, 2013</p> <p>Paratelecrinus cubensis (Carpenter, 1881).</p> <p>Antedon cubensis: Pourtalès 1869: 356 (in part); 1878: 214-215 (in part).</p> <p>Atelecrinus cubensis Carpenter, 1881: 15-19, pl. 1 fig. 7; 1882: 491-492; 1888: 70-72. A.H. Clark 1907: 155. Hartlaub 1912: 281, 386, 484, pl. 14, figs 3, 8, 9.</p> <p>Atelecrinus pourtalesi: A.H. Clark 1907: 4. H.L. Clark 1941: 13.</p> <p>Atelecrinus balanoides: A.H. Clark and A.M Clark 1967: 819, 823-831 (in part).</p> <p>Paratelecrinus cubensis: C.G. Messing 2013: 22-24, figs 9, 10.</p> <p>Material examined.</p> <p> MBM287771, 1 specimen; Western Pacific, Kocebu Guyot, R / V <i>KeXue</i> station FX-Dive177; 17°21′14″N, 153°08′35″E; 1294 m depth, 11 April 2018, hard substrate.</p> <p>Description.</p> <p>The middle and distal parts of the rays of the specimen are missing, broken off at IIbr3, IIbr6, and IIbr9 (Fig. 2).</p> <p>Centrodorsal conical, base diameter 3.0 mm, H/D 1.3; interradial margin with U-shaped depression (Fig. 3). Cirrus sockets distributed in 10 columns, with strong fulcral tubercles. Cirri XL, only one complete peripheral cirrus (Fig. 4b) 69.1 mm long and with 31 segments; c1-3 short and cirrals gradually increasing in length, with expanded distal ends; c8-c13 longest, L/W 6.7; penultimate cirral squarish, with opposing spine weak or absent, terminal claw curled (Fig. 5b). Apical cirrus of 22 segments, 15.0 mm long; c5-c7 longest, L/W 3.4 (Fig. 4a).</p> <p>Basals form a complete ring, separated from centrodorsal by distinct ligamentous bundles, especially interradially; externally visible portion of basals swollen interradially and then narrowing laterally, with a concave lower edge interradially and an overall inverted V-shape (Fig. 6c). Radials are very short, W/L 3.2. Lateral margin of radials clearly visible, separating adjacent brachitaxes (Fig. 6c).</p> <p>Arms 10, 2.9-8.3 mm long (Fig. 3). First brachitaxes and proximal rays with moderately developed synarthrial tubercles. Ibr1 rectangular, with V-shaped distal margin and thin projections on lateral margins, W/L 2.5. Iax2 rhombic, laterally margin with wing-like flange, lower edge distinctly convex, W/L 1.1. IIbr1, W/L 2.7, outer lateral margin longer and slightly curled inward (Fig. 6a). IIbr2, W/L 1.3, irregularly square, outer lateral margin longer, distal margin wider, proximal margin V shaped, with sufficient clearance from adjacent IIbr2. IIbr3+4 longer interiorly, W/L 1.2, 1.7 mm across. Middle brachials wedge-shaped, W/L 1.8. Distal brachials wedge-shaped and longer than wide, with distal ends slightly raised, W/L 0.6 (Fig. 6b). Syzygies at (3+4), (6+7), (9+10).</p> <p>Distribution.</p> <p> Previous records of <i>P. cubensis</i> have been only collected in the deep sea off the Bahamas and Cuba (567-892 m) (Messing 2013). The current study is the first report of <i>P. cubensis</i> from Kocebu Guyot, which extends the known geographical distribution of this species to the Western Pacific Ocean (Fig. 1). Furthermore, the new record is the deepest known observation of <i>P. cubensis</i>; at 1294 m, this observation extends the depth of this feather star beyond 1000 m.</p> <p> McClain and Hardy (2010) have suggested that bathymetric gradients may impose limitations on the range of species compared to horizontal distances, and that the geographic distribution of species may be more frequent where water depths are deeper. Based on this hypothesis, the large gap in the geographic distribution of <i>P. cubensis</i> seems reasonable. Furthermore, biodiversity correlates with latitude, showing patterns of tropical peaks and polar declines in species richness (Mannion et al. 2014). The collection site is consistent with the latitudinal distribution of previous records, which supports the very large geographic distribution of <i>P. cubensis</i>.</p>Published as part of <i>Mei, Zijie, Sha, Zhongli & Sun, Shao'e, 2023, Going deeper and further: a range and depth extension for the deep-sea feather star Paratelecrinus cubensis (Carpenter, 1881) (Comatulida, Atelecrinidae), first record from the Western Pacific, pp. 103-113 in ZooKeys 1184</i> on page 103, DOI: 10.3897/zookeys.1184.11057

Supplementary material 1 from: Mei Z, Sha Z, Sun S (2023) Going deeper and further: a range and depth extension for the deep-sea feather star Paratelecrinus cubensis (Carpenter, 1881) (Comatulida, Atelecrinidae), first record from the Western Pacific. ZooKeys 1184: 103-113. https://doi.org/10.3897/zookeys.1184.110577

Sequence information needed to construct phylogenetic tree

Development and nuclear characteristic testing of a mobile miniature fission ionization chamber neutron detector

BackgroundThe miniature fission ionization chamber is a widely used neutron detector for the in-core neutron flux monitoring of a nuclear reactor. Typically, the in-core neutron flux rate measurement system of a domestic CPR1000 nuclear power unit adopts a mobile miniature fission ionization chamber as the neutron probe to measure the neutron flux of the reactor and provide an in-core neutron flux distribution map during the operation. Therefore, it is an important piece of safety and control equipment for nuclear power plants.PurposeThis study aims to develope a mobile miniature fission ionization chamber neutron detector according to the service conditions and technical requirements of current foreign products.MethodsThe nuclear properties of self-made fission ionization chamber neutron detector was developed strictly following the national standard GB/T 7164-2022 and the industry standard NB/T 20215-2013. The gamma sensitivity was tested and compared with a reference commercial fission detector using a 60Co gamma source. The thermal neutron detection characteristic, including the length and slope of plateau, the thermal neutron sensitivity and linearity were tested in one test channel of the China Mianyang Research Reactor (CMRR) with neutron flux from 1×109 n∙cm-2∙s-1 to 4×1013 n∙cm-2∙s-1.Results & ConclusionsThe test results indicate that "domestic substitution" of this in-core safety product can be achieved, and the nuclear characteristics of self-developed prototypes are comparable to those of foreign products

The impact of bone marrow irradiation dose on acute haematologic toxicity in cervical cancer patients treated with concurrent chemoradiotherapy

Abstract Objective To evaluate the impact of bone marrow (BM) irradiation dose on acute haematologic toxicity (HT) in concurrent chemoradiotherapy for cervical cancer. Methods Sixty-nine patients with cervical cancer treated with curative or postoperative adjuvant therapy received weekly cisplatin concurrent chemotherapy (CCT) and intensity-modulated radiation therapy (IMRT). The whole pelvic bone marrow (PBM) was delineated and divided into three subsites: ilium (IL), lower pelvis (LP), and lumbosacral spine (LS). Associations between clinical variables, dose volume of BM, including PBM, IL, LP, and LS in the form of x-Vy (volume receiving y Gy for x), and blood cell count nadir were tested using linear regression models. Receiver operating characteristic (ROC) curve analysis was further used to analyse the cutoff values of the variables with p < 0.05 in the multivariate analysis. Results In 69 patients, the haemoglobin nadir was positive correlated with baseline haemoglobin (p < 0.001), negative correlated with relative LP-V10 (p = 0.005), relative LP-V25 (p = 0.002), relative LP-V50 (p = 0.007), relative LP-mean (p = 0.003), absolute LP-V15 (p = 0.049), absolute LP-V25 (p = 0.004) and absolute LP-V30 (p = 0.009). The platelet nadir was positive correlated with baseline platelets (p = 0.048) and negative correlated with relative LP-V40 (p = 0.028), but there was no significant variable in absolute radiation volume by multivariate analysis. No variables related to the neutrophil nadir were found, and the 69 patients were divided into group A (43 cases) receiving 3–4 cycles of CCT and group B (26 cases) receiving 5–6 cycles of CCT. In group A, the relative IL-V15 (p = 0.014), the relative IL-V50 (p = 0.010) and the absolute LP-V50 (p = 0.011) were negative correlated with the neutrophil nadir. No significant variable was found in group B. No significant variables related to the lymphocyte nadir were found, and the neutrophil-to-lymphocyte ratio (NLR) was analysed. Age (p < 0.05), relative LP-V15 (p = 0.037) and absolute PBM-mean (p < 0.001) were found to be negative related to NLR. Conclusion The dosimetric parameters of relative irradiated volume of BM have more statistically significant datas on acute HT than absolute irradiated volume. The nadir of haemoglobin and platelets and the vertice of NLR were more affected by the irradiation dose to LP, while neutrophils were more affected by the dose to IL. Acute HT was negative related to both low-dose irradiation (V10-30) and high-dose irradiation (V40, V50). For more than 4 cycles of CCT, the effect of BM irradiation on the neutrophils nadir was masked by chemotherapy