11,246 research outputs found
Pseudo-spin-valve with L 10 (111)-oriented FePt fixed layer
No full textRecently we proposed a spin torque oscillator where the fixed layer has its magnetization easy-axis tilted with respect to the film plane to simultaneously achieve zero-field operation and high output power [Y. Zhou, C. L. Zha, S. Bonetti, J. Persson, and J. Åkerman, Appl. Phys. Lett. 92, 262508 (2008)]. Here we take the first step toward the realization of this device and fabricate successfully a pseudo-spin-valve using an L 10 (111)-oriented FePt fixed layer with tilted magnetocrystalline anisotropy. A total magnetoresistance (MR) of 0.86% is experimentally observed for the standard pseudo-spin-valve of the L 10 FePt/Cu/NiFe structure in applied fields up to 1.5 T. While part of the MR may originate from the FePt film alone, the dominating part of MR correlates with switching of the NiFe free layer. © 2009 American Institute of Physics.link_to_subscribed_fulltex
Spin-torque oscillator with tilted fixed layer magnetization
No full textA spin-torque oscillator with a fixed layer magnetization tilted out of the film plane is capable of strong microwave signal generation in zero magnetic field. Through numerical simulations, we study the microwave signal generation as a function of drive current for two realistic tilt angles. The tilted magnetization of the fixed layer can be achieved by using a material with high out-of-plane magnetocrystalline anisotropy, such as L1(0) FePt. (C) 2008 American Institute of Physics
Zero-field precession and hysteretic threshold currents in a spin torque nano device with tilted polarizer
No full textUsing nonlinear system theory and numerical simulations, we map out the static and dynamic phase diagrams in the zero applied field of a spin torque nano device with a tilted polarizer (TP). We find that for sufficiently large currents, even very small tilt angles (beta > 1 degrees) will lead to steady free layer precession in zero field. Within a rather large range of tilt angles, 1 degrees < beta < 19 degrees, we find coexisting static states and hysteretic switching between these using only current. In a more narrow window (1 degrees < beta < 5 degrees) one of the static states turns into a limit cycle (precession). The coexistence of current-driven static and dynamic states in the zero magnetic field is unique to the TP device and leads to large hysteresis in the upper and lower threshold currents for its operation. The nano device with TP can facilitate the generation of large amplitude mode of spin torque signals without the need for cumbersome magnetic field sources and thus should be very important for future telecommunication applications based on spin transfer torque effects
A new C-glycosylflavone from the leaves of Cycas panzhihuaensis
No full textA new C-glycosylflavone, named panzhihuacycaside (1), was isolated from the leaves of Cycas panzhihuaensis L. Zhou et S. Y. Yang (Cycadaceae) along with 2,3-dihydrohinokiflavone (2), 5,5",7,7", 4',4'"-hexahydroxy-(2',8")-biflavone (3), vanillic acid (4), P-sitosterol (5) and daucosterol (6). Their structures were elucidated by spectral and chemical evidence
Cl-Doped Li<sub>10</sub>SnP<sub>2</sub>S<sub>12</sub> with Enhanced Ionic Conductivity and Lower Li-Ion Migration Barrier
No full textAll-solid-state
lithium batteries based on sulfide solid electrolytes
have attracted much attention because of their high ionic conductivity.
Li10SnP2S12 (LSPS) has the same structure
as Li10GeP2S12, and there is little
difference in ionic conductivity between them, but the preparation
cost of LSPS is lower. Here, Cl doping is used to improve the electrochemical
stability of the LSPS to the anode and the Li-ion transport performance.
Among them, Li9.9SnP2S11.9Cl0.1 had a high ion conductivity of 2.62 mS cm–1 after cold pressure. On the crystal structure, X-ray diffraction
Rietveld refinement indicated that the Cl-substituted portion S is
successfully incorporated into the lattice of the LSPS, increasing
Li-ion vacancies and reducing the distance between adjacent Li-ion
distributed along the c-axis, these are conducive
to Li-ion transmission. The temperature-dependent AC impedance experiment
and density functional theory calculation show that doping with Cl
makes Li9.9SnP2S11.9Cl0.1 have a lower activation energy. The assembled lithium symmetric
batteries show that the doping of Cl promotes the stability of the
interface between LSPS and the lithium metal anode. The charge–discharge
tests of all-solid-state batteries using Li9.9SnP2S11.9Cl0.1 as electrolyte have confirmed that
Cl doping can improve the electrochemical performance of LSPS, which
have a higher specific capacity and cycle life
Neuronal K+-Cl- cotransporter KCC2 as a promising drug target for epilepsy treatment
No full textEpilepsy is a prevalent neurological disorder characterized by unprovoked seizures. γ-Aminobutyric acid (GABA) serves as the primary fast inhibitory neurotransmitter in the brain, and GABA binding to the GABAA receptor (GABAAR) regulates Cl- and bicarbonate (HCO3-) influx or efflux through the channel pore, leading to GABAergic inhibition or excitation, respectively. The neuron-specific K+-Cl- cotransporter 2 (KCC2) is essential for maintaining a low intracellular Cl- concentration, ensuring GABAAR-mediated inhibition. Impaired KCC2 function results in GABAergic excitation associated with epileptic activity. Loss-of-function mutations and altered expression of KCC2 lead to elevated [Cl-]i and compromised synaptic inhibition, contributing to epilepsy pathogenesis in human patients. KCC2 antagonism studies demonstrate the necessity of limiting neuronal hyperexcitability within the brain, as reduced KCC2 functioning leads to seizure activity. Strategies focusing on direct (enhancing KCC2 activation) and indirect KCC2 modulation (altering KCC2 phosphorylation and transcription) have proven effective in attenuating seizure severity and exhibiting anti-convulsant properties. These findings highlight KCC2 as a promising therapeutic target for treating epilepsy. Recent advances in understanding KCC2 regulatory mechanisms, particularly via signaling pathways such as WNK, PKC, BDNF, and its receptor TrkB, have led to the discovery of novel small molecules that modulate KCC2. Inhibiting WNK kinase or utilizing newly discovered KCC2 agonists has demonstrated KCC2 activation and seizure attenuation in animal models. This review discusses the role of KCC2 in epilepsy and evaluates its potential as a drug target for epilepsy treatment by exploring various strategies to regulate KCC2 activity
Miobdelus wangi He & Zhou 2018, sp. nov.
No full text2. Miobdelus wangi He and Zhou, sp. nov. (Figs. 2-1, 2-2) Type locality: CHINA, Sichuan Province, Yajiang County. Type material. Holotype male, CHINA: Sichuan Province, Yajiang County, 3400 m, mixed broadleafconifer forest, pitfall traps, 15–18.VII.2001, coll. Xiaodong Yu & Hongzhang Zhou (IZ-CAS). Paratypes: CHINA: Sichuan Province: 4 males, 3 females, same data as holotype (IZ-CAS). Measurements. Body length: 13.7–16.9 mm. CL: 0.72; EL: 2.37; ELS: 1.01; EW: 2.72; HL: 2.18; HW: 2.40; PO: 0.99; PL: 2.68; PW: 2.24. Description. Medium sized species. Body relatively elongate, totally black; head and pronotum with slight brassy sheen; elytra paler, dark reddish-brown, with small patches of brownish tomentose patches on humeral angles and middle of lateral sides; maxillary and labial palpi black to dark brunneous; antennae dark brunneous, with apical segments vaguely paler; legs brownish black, with tibia and tarsus covered with dense brownish pubescence; pubescence of dorsal side of head, pronotum and abdominal tergites brownish black, and that of elytra somewhat paler. Head of rounded quadrangular shape, with slightly curved lateral sides and obtusely rounded posterior angles, slightly wider than long (ratio 1.10); eyes relatively smaller than most congeners and slightly protruding, shorter than tempora (ratio 0.73) in dorsal view; punctation and pubescence on dorsal surface of head dense, punctation robust, gradually becoming sparser toward clypeus, with shiny interspaces; interspaces without microsculpture; head disc with about five large pit-like punctures on each side of epicranial line. Y-shaped epicranial line clearly present on head disc. Antennae moderately long, segment 3 about as long as segment 2 (ratio 1.06), segments 4 to 7 slightly longer than wide to about as long as wide, segments 8 to 10 distinctly wider than long, last segment slightly narrower than segment 10. Pronotum longer than wide (ratio 1.20), with almost parallel lateral sides and widely rounded posterior angles, slightly narrowed posteriad from posterior third; narrow marginal groove disappearing downwards at posterior fourth of pronotal length; impunctate midline distinctly and entirely present; punctation and pubescence on disc about same as that on dorsal surface of head, interspace without microsculpture. Scutellum finely punctate and setose on entire surface, almost totally black, with some yellowish pubescence on basal part. Elytra relatively short, slightly dilated posteriad; elytral length shorter than pronotum along midline, with a ratio of 0.38 along suture and a ratio of 0.88 along sides; elytral punctation fine and dense, granulose; pubescence black or dark reddish-brown, with patches of dark brownish tomentose pubescence on humeral angles and about poster third of lateral sides. Wings markedly reduced. Abdomen with pale apical seam of palisade setae. Abdominal tergite 2 punctate and pubescent on entire surface; all visible abdominal tergites finely and densely punctate and pubescent; visible tergites 1 to 3 each with a pair of black tomentose patches; visible tergite 4 with a pair of golden yellowish tomentose patches, surrounded by patches of black tomentose pubescence on lateral sides; visible tergite 5 with a pair of tomentose patches similar with that on visible tergite 4, but markedly smaller and darker. Male. Abdominal sternite 8 with wide and shallow medioapical emargination. Sternite 9 relatively long; apical margin widely rounded, with markedly shallow emargination; tapered basal portion markedly elongate (Fig. 2-2 G). Tergite 10 shaped as in Fig. 2-2 D, with subacuate apex, sparsely setose. Aedeagus shaped as in Figs. 2-1 B, C, 2-2 A–C, median lobe triangular, constricted subapically, with rounded but narrow apex; apical portion of paramere elongate, shaped as in Figs. 2-1 D, 2-2 E, with sensory peg setae arranged along lateral sides, not numerous. Female. Second gonocoxite and tergite 10 shaped as in Figs. 2-1 E, 2-2 F, H. Distribution. Miobdelus wangi He and Zhou, sp. nov. is at present known only from the type locality in western Sichuan Province. Notes. Miobdelus wangi He and Zhou, sp. nov. can be easily distinguished from other congeners by the uniquely shaped aedeagus, the patterns of tomentose pubescence on elytra and abdominal tergites (other species have the pubescence on these parts in different patterns), and relatively small eyes. Etymology. The species is named in honor of Dr. Chengbin Wang, a previous colleague from our research team, for his generous help with this study and other studies of the subtribe Staphylinina.Published as part of He, Liang & Zhou, Hong-Zhang, 2018, Taxonomy of the genus Miobdelus Sharp, 1889 (Coleoptera: Staphylinidae: Staphylinini) and five new species from China, pp. 301-353 in Zootaxa 4377 (3) on pages 309-312, DOI: 10.11646/zootaxa.4377.3.1, http://zenodo.org/record/116443
Miobdelus chrysanthemoides He & Zhou 2018, sp. nov.
No full text3. Miobdelus chrysanthemoides He and Zhou, sp. nov. (Figs.3-1, 3-2) Type locality: CHINA, Sichuan Province, Luding County, Moxi Town, Hailuogou. Type material. Holotype male, CHINA: Sichuan Province, Luding County, Moxi Town, Hailuogou, 2775 m, pitfall traps, 16.V.2009, coll. Yulingzi Zhou (IZ-CAS). Paratypes: CHINA: Sichuan Province: 2 females, same data as holotype (IZ-CAS). Measurements. Body length: 12.4–15.4 mm. CL: 0.69; EL: 2.71; ELS: 1.48; EW: 2.75; HL: 1.95; HW: 2.19; PO: 0.88; PL: 2.35; PW: 1.97. Description. Medium sized species. Body relatively elongate, black; head and pronotum with slightly brassy sheen; elytra paler, dark reddish-brown, with small patches of brownish tomentose pubescence on humeral angles and middle of lateral sides; maxillary and labial palpi dark brunneous; antennae black, with basal part of each segments somewhat paler, tending to be dark brunneous; apical segments of antennae vaguely paler; legs black, with tibia and tarsus covered with dense brownish pubescence; disc of head covered with long and dense yellowish pubescence; pubescence of dorsal side of pronotum and elytra dark reddish-brown, and that of abdominal tergites black. Head of rounded quadrangular shape, with obtusely rounded posterior angles, wider than long (ratio 1.12); eyes moderately large and slightly protruding, appreciably shorter than tempora (ratio 0.78) in dorsal view; punctation and pubescence on dorsal surface of head dense, punctation markedly robust, gradually becoming sparser toward clypeus, with shiny interspaces; pubescence markedly longer and denser than most congeners of Miobdelus; interspaces without microsculpture; head disc with about five large pit-like punctures on each side of epicranial line. Anterior part of Y-shaped epicranial line clearly present on head disc, with basal part becoming slightly vaguer. Antennae moderately long, segment 3 about as long as segment 2 (ratio 1.02), segments 4 to 9 distinctly longer than wide, gradually becoming wider, segment 10 about as long as wide, last segment slightly narrower than segment 10. Pronotum distinctly longer than wide (ratio 1.19), with widely rounded posterior angles; anterior half slightly wider; narrow marginal groove disappearing downwards at posterior fourth of pronotal length; impunctate midline robust, distinctly and entirely present; punctation on pronotal disc about same as that on dorsal surface of head, slightly finer, interspace without microsculpture; pubescence moderately dense and long, much sparser and shorter than that on head disc. Scutellum finely punctate and setose on entire surface, totally black. Elytra moderately long, elytral length distinctly shorter (ratio 0.63) along suture but slightly longer (ratio 1.15) along sides than pronotum along midline, slightly dilated posteriad; elytral punctation fine and dense, granulose; pubescence dark reddish-brown, with patches of dark brownish tomentose on humeral angles and about middle of lateral sides. Wings fully developed. Abdomen without pale apical seam of palisade setae, but apical margin of visible tergites each with a pair of yellowish brown tomentose spots near later margins. Abdominal tergite 2 only punctate and pubescent along posterior margin; all visible abdominal tergites finely and densely punctate and pubescent; visible tergites 1 and 2 each with a pair of black tomentose patches; visible tergites 3 with a large patch of black tomentose pubescence in middle; visible tergite 4 with a large patch of golden yellowish tomentose pubescence; visible tergite 5 with a pair of small black tomentose patches, surrounded by some yellowish tomentose pubescence. Male. Abdominal sternite 8 with moderately wide and relatively deep medioapical emargination. Sternite 9 moderately long, gradually narrowed from basal part to apical part; apical margin with markedly shallow emargination; tapered basal portion moderately long (Fig. 3-2 G). Tergite 10 shaped as in Fig. 3-2 D, sparsely setose. Aedeagus short and robust, with apical portion markedly short, shaped as in Figs. 3-1 B, C, 3-2 A–C; paramere almost reaching apex of median lobe, shaped as in Figs. 3-1 D, 3-2 E, with sensory peg setae arranged along lateral sides, not numerous. Female. Second gonocoxite and tergite 10 shaped as in Figs. 3-1 E, 3-2 F, H. Distribution. Miobdelus chrysanthemoides He and Zhou, sp. nov. is at present known only from the type locality in central Sichuan Province. Notes. Miobdelus chrysanthemoides He and Zhou, sp. nov. can be quite easily distinguished from other species by the short and robust aedeagus and the long and dense yellowish pubescence on the dorsal head. Etymology. The species epithet chrysanthemoides is composed of Greek stems chrys (golden, beautiful), anthem - (flower, as like chrysanthemums) and suffix – oides, to indicate the golden-haired mark on the head and abdomen.Published as part of He, Liang & Zhou, Hong-Zhang, 2018, Taxonomy of the genus Miobdelus Sharp, 1889 (Coleoptera: Staphylinidae: Staphylinini) and five new species from China, pp. 301-353 in Zootaxa 4377 (3) on pages 312-315, DOI: 10.11646/zootaxa.4377.3.1, http://zenodo.org/record/116443
Pararanguna hemicyclia Naruse, Chia & Zhou 2018
No full textPararanguna hemicyclia Naruse, Chia & Zhou, 2018 Material examined Paratype CHINA – Yunnan Province • 1 ♂, CW 14.0 mm, CL 11.9 mm; Fengqing County: Dashan Village, Xueshan Town; [24.466° N, 99.780° E]; 1 Feb. 2004; Yang Zheng Bing leg.; ZRC 2013.0559.Published as part of Pati, Sameer K., 2022, Gurumon gurumayum, a new genus and new species of freshwater crab (Decapoda: Brachyura: Potamidae) from Arunachal Pradesh, northeastern India, pp. 28-45 in European Journal of Taxonomy 847 on page 33, DOI: 10.5852/ejt.2022.847.1979, http://zenodo.org/record/733417
Microwave generation of tilted-polarizer spin torque oscillator
No full textMicrowave frequency generation in a spin torque oscillator (STO) with a tilted fixed layer magnetization is studied using numerical simulation of the Landau-Lifshitz-Gilbert-Slonczewski equation. The dependence of the STO free layer precession frequency on drive current is determined as a function of fixed layer tilt angle. We find that zero-field STO operation is possible for almost all tilt angles, which allow for great freedom in choosing the detailed layer structure of the STO. © 2009 American Institute of Physics.link_to_subscribed_fulltex
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