710 research outputs found
Autism spectrum disorder causes, mechanisms, and treatments: focus on neuronal synapses
No full textAutism spectrum disorder (ASD) is a group of developmental disabilities characterized by impairments in social interaction and communication and restricted and repetitive interests/behaviors. Advances in human genomics have identified a large number of genetic variations associated with ASD. These associations are being rapidly verified by a growing number of studies using a variety of approaches, including mouse genetics. These studies have also identified key mechanisms underlying the pathogenesis of ASD, many of which involve synaptic dysfunctions, and have investigated novel, mechanism-based therapeutic strategies. This review will try to integrate these three key aspects of ASD research: human genetics, animal models, and potential treatments. Continued efforts in this direction should ultimately reveal core mechanisms that account for a larger fraction of ASD cases and identify neural mechanisms associated with specific ASD symptoms, providing important clues to efficient ASD treatment.586311Nscopu
GIT1유전자 결손 형질전환 마우스 및 이를 이용한 약물 스크리닝 방법
No full textProvided is a method of using any mammal except humans, in particular, a mammal as an attention deficit hyperactivity disorder model, wherein genes of G protein-coupled receptor kinase interacting protein 1 (GIT1) as a neuronal synapse protein in the brain are knocked out from the mammal. In addition, disclosed is analysis of GIT1 knock-out mice in aspects of molecular biology, cellular biology, electrical biology and animal behavior and, more particularly, a screening method of novel drug, wherein excessive behavior as an attention deficit hyperactive disorder as well as recovery of theta wave in the frontal lobe are observed by administering a candidate material of the drug, thereby inducing recovery of the attention deficit hyperactivity disorder
Story of Adeline Yen Mah
No full textProducer, Eleanor Morris ; narrator, Connie Booth.Adeline Yen Mah, the author of Falling leaves, traces her and her family's life from Shanghai of the 1930s to the Cultural Revolution, through her life as a doctor in California
Wallastra elenderae Mah 2018, n. gen.
No full textWallastra elenderae n. gen. n. sp. Figure 37 A–G Type species. Wallastra elenderae n. sp. by monotypy. Etymology. This genus and species are named for dear friend, opera singer, and co-author of the textbook Introductory Physics, Ms. Elender Wall (1969–2016). Diagnosis. Body strongly stellate (R/r=3.46) with elongate, slender arms, weakly curved interradial arcs (Fig. 37A, F). Abactinal plates bare, surface mostly bare and smooth (Fig. 37B), especially on distal disk regions adjacent to superomarginals and along arms. Central disk plates with one to several, widely distributed button-like granules. Superomarginals wide to quadrate in shape, with mostly bare surface, or widely distributed coarse granules occur (Fig. 37D). Each actinal plate covered with closely articulated granules, most plates with a single large bivalve pedicellaria (Fig. 37E). Furrow spines four or five (Fig. 37G). Comments. Based on comparisons with other goniasterid taxa, the species described here cannot be easily reconciled with known goniasterid genera, and therefore the new genus Wallastra is recognized. Wallastra n. gen. lacks the crystalline tubercles embedded in the surface of the abactinal plates, which identifies all species of Astroceramus as well as the superomarginals abutted over the radius of each arm. Most species of Astroceramus also possess one or two enlarged subambulacral spines that are absent from Wallastra. Abactinal plates on Wallastra n. gen. possess one to approximately eight to 10 coarse granules embedded in the plate surface but are otherwise bare and smooth. Granules abruptly disappear on arm plates where abactinal plates become flatter and are entirely devoid of surficial accessories. This character is reminiscent of the abrupt change between plates that defines the difference between Circeaster and Lydiaster. In Circeaster, abactinal arm plates are abruptly larger whereas those in Lydiaster remain relatively similar in size on the arm and disk. However, Lydiaster possesses much larger and wider marginal plates with a stronger abactinal facing, a thicker and more stout body shape and widespread spinelets that are absent from Wallastra n. gen. Two species of Circeaster, C. sandrae (South and Central Pacific) and especially C. pullus (North Pacific) display similar abactinal and marginal plate patterns to both Wallastra n. gen. and Astroceramus. Occurrence. Solomon Islands and Western Indian Ocean, between Mayotte and the Glorioso Islands, 550–836 m. Description. Body strongly stellate (R/r=3.46), arms elongate, tapering. Interradial arcs weakly curved to nearly straight (Fig. 37A). Abactinal surface flat, composed of round to polygonal abutted plates (Fig. 37A, B), which are flush with superomarginal plate surface (Fig. 37D). Approximately three rows of abactinal plates (at R= 10.4 cm) extending along arm to terminus (Fig. 37C), decreasing in number to a single row of wide then very narrow, irregularly shaped, strongly convex plates along distalmost arm region. Plates largest and most polygonal along papular (radial regions) with smallest and most irregular plates occurring interradially. Plates with discrete peripheral row of quadrate to polygonal shaped granules,12–30, mostly 15–25, with approximately four to five granules present per side (Fig. 37B). Peripheral granules largest on disk occupying 1/3 to 1/5 of the total width of each plate becoming substantially smaller on arm plates, occupying only approximately 1/6 to 1/10 of the total plate distance. Peripheral granules on arm more rounded and nearly flush with plate surface versus those on disk which are raised and sit above the plane of the abactinal plate surface. Abactinal plate surfaces on the disk possess one to 15 (mostly two to six) large, coarse widely spaced granules but are otherwise smooth, bare and are mostly devoid of other structures or accessories. Granules are widely spaced on all but the plates flanking the polygonal shaped madreporite. Of the seven plates which flank the madreporite, four possess abundant and closely spaced coarse granules all but covering the plate surface. This side of the madreporite with granule-covered plates with one to two irregularly spaced rows of plates with similarly abundant granule-covered plates. Two plates observed each with a large paddle-shaped pedicellaria (approximately 1.5–2.0 mm width) present in the center of each plate. These large coarse button-like granules decrease in number farther away from the center of the disk, disappearing completely on the disk edge, arm base and along the surface of the arm plates. The absence of the button-like granule leaves a distinct concavity on the plate where it has been removed, otherwise the surface is flat and smooth. Papulae were extended on specimen examined with six numbering around each plate along radial regions at the base of each arm extending from the radial region of the disk. Superomarginal and inferomarginal plates, approximately 62–66 per interradius. Plates wide, quadrate in shape with flattened surface interradially but becoming more elongate and tumid distally, becoming much more strongly convex adjacent to arm tip. Superomarginals and inferomarginals with 1:1 correspondence interradially becoming more offset distally, showing a more zigzag contact along the arm. Distalmost three to four superomarginals abutted over midline. Superomarginals with one to approximately 25 coarse, round button-like, widely spaced granules present on each plate surface, granules are most abundant interradially, gradually decreasing and then disappearing completely along plates present on the arm (Fig. 37D). When removed, disk granules leave a distinct, concave pitting on the superomarginal plate surface. Inferomarginal plate surfaces show same general pattern but interradial plates also possess a dense row of coarse, polygonal granules identical to those which compose the peripheral granule layer around the marginal plates (Fig. 37D). Peripheral granules around superomarginals, polygonal to narrowly quadrate, approximately 30–80, mostly 40–60 forming (15 per edge) narrow border around superomarginal plates becoming nearly indistinct near arm terminus. Peripheral granules around inferomarginals similar in size and number except for those in contact with granules on the actinal plate surface, which are slightly larger than those on the other sides of the inferomarginal plate. Granules on the inferomarginal/actinal plate contact are much larger, coarser, in close contact, and similar in overall appearance. As with superomarginals, granules are most numerous interradially, with numbers decreasing and disappearing entirely on inferomarginal plate surface along the arm, especially distally adjacent to the arm terminus. Terminal plate is large, triangular in shape, approximately the size of four adjacent superomarginal plates, with bare surface and a large blunt spine on the tip. Actinal surface composed of approximately three full series in chevron-like pattern, with irregular incomplete series adjacent to contact with inferomarginal plates (Fig. 37E). Actinal plates quadrate to polygonal in outline, all plates on disk covered by coarse, closely distributed polygonal to round granules, four to 12 per plate. Approximately 1 granule counted along a 1.0 mm line. Actinal plates along arm with decreasing number of granules, in some cases disappearing from plate surface. Large (1.0–2.0 mm wide) trapezoid shaped pedicellariae (Figs. 37E, G), each with short, jagged complimentary valves, numbering one per plate, occurring on approximately 50% of actinal plates, variably present throughout each interradius. Furrow spines four in a linear series increasing to five distally, quadrate to triangular in cross-section with spines flattening out farther along arm, becoming individually narrower and more prominent (Fig. 37G). Variably, some spines are flattened and are more wedge-shaped. Furrow spines mostly blunt and smooth but most proximal spines with notches or some texturing on each spine tip. Furrow spines are set off by a discrete space, then two to four short triangular to rounded subambulacral spines, less than 25% of the length of each furrow spine. When only two subambulacrals are present, they occur on either side of the adambulacral plate, flanking a large bivalve pedicellaria with large rectangular valves with jagged tips, similar to those on actinal surface (Fig. 37G). Subambulacral spines transition from two short enlarged granules to a single enlarged blunt spine on distalmost adambulacral plates. Subambulacral pedicellariae occur in a continuous series along the adambulacral plates on the disk but gradually disappear along the transition from disk to arm. Pedicellariae are in turn, flanked by a row of three, large, blunt spines, quadrate to rounded in cross-section, which are two to three times as thick as the adjacent actinal granules. Pedicellariae set off from both the furrow spines and the thickened subambulacrals by discrete bare spaces. Pedicellariae are absent on a minority of plates, and are replaced by a series of two to four small polygonal granules similar to those on the actinal surface. Remainder of adambulacral surface covered by four to 20 thick, mostly 10 to 15 polygonal granules, best developed along arm after pedicellariae series has terminated. Oral plates with six to eight thick spines, ranging from thickened quadrate to flattened and triangular in crosssection with thin, flattened paddle like spines projecting into oral region from each paired oral plate. Oral plates with four or five thick subambulacral spines, each two to four times as thick as the furrow spines with six to eight, short paired, irregular, triangular granules on each side of the oral plate contact along the midline. Color in life, disk is light orange with darker orange arms and solid dark marginal plates. Material Examined. Holotype: MNHN-IE-2013-17165. Western Indian Ocean, between Mayotte and the Glorioso Islands, 12° 18 'S, 46° 27' E to 12 ° 17 'S, 46 ° 28' E, 842– 836m, Coll. S. Samadi et al. BIOMAGLO DW 4792, 22 Jan 2017, leg 1. 1 wet spec. R=10.4 r=3.0. Paratype: IE-2007-1291. Solomon Islands 8°16’S 160° 43’E, 550 m, Coll. Richer & Boissellier, 15 Sept. 2007. N/ O Alis, SALOMONBOA 3 DW 2792 1 wet spec. R=9.3 (arm twisted) r=3.2Published as part of Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, pp. 1-116 in Zootaxa 4539 (1) on pages 98-100, DOI: 10.11646/zootaxa.4539.1.1, http://zenodo.org/record/261591
전해도금법으로 제조된 리튬 이온 이차전지용 Sn 계 음극의 전기화학적 특성
No full text학위논문(박사) - 한국과학기술원 : 신소재공학과, 2006.2, [ [xii], 164 p. ]The preparation of Sn-based anodes for Li-ion batteries is a viable, advantageous process, for the following reasons; First, the electroplating process is simpler than currently-used powder process because there is no need for any binder or conductive agents. Second, owing to their low impurity, a comparatively high initial coulombic efficiency can be obtained. However, a Sn anode has the intrinsic problem of crumbling due to the large amount of volume expansion (up to 300 %) during Li insertion, resulting in the electrical isolation of the Sn anode from the Cu substrate with a significant decrease in the charge/discharge capacity of cell.
In order to overcome the problem, the possibility of using a nodule-type Cu substrate was explored by comparison with a smooth and a pyramid-type Cu substrate, and its proper aging condition was proposed. Comparing the cycle performance of the Sn electrodes electro-plated on the three different Cu substrates, the Sn electrode electroplated on the nodule-type showed the highest reversible capacity , , and , which demonstrates that the nodule-type Cu substrate enhanced the adhesion and electrical contact properties between the Sn and the Cu substrate. In addition, Sn an-ode electroplated and aged for 1 h at 200℃ exhibited a high reversible capacity and cycle performance, which is due to the enhanced adhesion strength by formation of the thin Sn phase. However, when aged for longer than 1 h at 200 ℃, the reversible capacity decreased due to the thickening of the inactive Sn phase. The best performance of the Sn anode was obtained when the Sn anode was electroplated on the nodule-type Cu substrate and aged for 1 h at 200 ℃, which exhibited high reversible capacity (~600 mAh/g) and good cycleability.
Recently, a strange phenomenon named as ‘high-voltage irreversible capacity’ was reported. This occurs during lithiation process of a Sn...한국과학기술원 : 신소재공학과
Effect of Plastic MAH Storage, 1-MCP, and Coating on Fruit Storability of ‘Sweet Gold’ and ‘Goldone’ Kiwifruit
No full textWe examined the modulation of ‘Sweet Gold’ and ‘Goldone’ kiwifruit (Actinidia spp.) ripening using modified atmosphere and humidity (MAH), 1-methylcyclopropene (1-MCP), and edible coating treatments up to 35 days after storage (DAS) at room temperature. The 1-MCP and coating treatments decreased [CO2] in both cultivars, whereas MAH treatment rapidly increased or decreased [CO2]. Use of 1-MCP highly preserved firmness in both cultivars, followed by coating. MAH sharply reduced approximately 17% of ‘Goldone’ fruit firmness at 7 DAS compared to other treatments. MAH, 1-MCP, and coating reduced weight loss in ‘Sweet Gold’ kiwifruits from 14 to 35 DAS. Coating prevented approximately 14% of weight loss in ‘Goldone’ fruits during storage by strong adherence to the fruit surface. The flesh of control and MAH-treated fruits of both cultivars exhibited reduced acidity during storage, increasing the soluble solids content to acidity ratio. The use of 1-MCP delayed a reduction in L* values of the peel color of ‘Sweet Gold’ kiwifruits, while reduced L* values of flesh color were mostly observed with control and MAH treatment in both fruit cultivars. The use of 1-MCP, coating, and MAH maintained high total phenolics, ABTS, and vitamin C levels in both cultivars at 14 and 28 DAS. Fruit ripening was delayed by coating and promoted by MAH treatment, while maintaining the quality and functional substances of the fruit
Bifunctional Hybrid Catalysts with Perovskite LaCo0.8Fe0.2O3 Nanowires and Reduced Graphene Oxide Sheets for an Efficient Li–O2 Battery Cathode
No full textIn this paper, bifunctional catalysts consisting of perovskite LaCo0.8Fe0.2O3 nanowires (LCFO NWs) with reduced graphene oxide (rGO) sheets were prepared for use in lithium-oxygen (Li-O2) battery cathodes. The prepared LCFO@rGO composite was explored as a cathode catalyst for Li-O2 batteries, resulting in an outstanding discharge capacity (ca. 7088.2 mAh g-1) at the first cycle. Moreover, a high stability of the O2-cathode with the LCFO@rGO catalyst was achieved over 56 cycles under the capacity limit of 500 mAh g-1 with a rate of 200 mA g-1, as compared to the Ketjenblack carbon and LCFO NWs. The enhanced electrochemical performance suggests that these hybrid composites of perovskite LCFO NWs with rGO nanosheets could be a perspective bifunctional catalyst for the cathode oxygen reduction and oxygen evolution reactions in the development of next-generation Li-O2 battery cathodes. © 2018 American Chemical Society.11Nsciescopu
Facile synthesis of monodispersed 3D hierarchical Fe3O4 nanostructures decorated r-GO as the negative electrodes for Li-ion batteries
No full textOne-pot solvothermal process is adopted to develop, 3D hierarchical Fe3O4 nanoparticles supported 2D reduced
graphene oxide sheets (Fe3O4/r-GO) as possible negative electrodes for lithium ion batteries. The synthesis
parameters are optimized to prepare agglomeration-free Fe3O4 nanostructures with uniform size and shape on r-
GO. The field emission scanning electron microscopic (FESEM) image reveals that the 3D hierarchical Fe3O4
nanostructures are uniformly decorated on r-GO. The physicochemical and functional properties of Fe3O4/r-GO
are systematically investigated using various techniques. The fabricated Fe3O4/r-GO electrode delivers an initial
discharge capacity of 1221 mAh g−1 at a current density of 100 mA g−1 and retains the specific capacity of
1560 mAh g−1 after 100 cycles. Fe3O4/r-GO significantly enhances cyclic performance, when compared with
bare Fe3O4 nanoparticles due to the uniform distribution of Fe3O4 nanoparticles on the graphene sheet with the
more number of electrochemically active sites.114Nsciescopu
Enhanced performance of sulfur-infiltrated bimodal mesoporous carbon foam by chemical solution deposition as cathode materials for lithium sulfur batteries
No full textAbstractThe porous carbon matrix is widely recognized to be a promising sulfur reservoir to improve the cycle life by suppressing the polysulfide dissolution in lithium sulfur batteries (LSB). Herein, we synthesized mesocellular carbon foam (MSUF-C) with bimodal mesopore (4 and 30 nm) and large pore volume (1.72 cm2/g) using MSUF silica as a template and employed it as both the sulfur reservoir and the conductive agent in the sulfur cathode. Sulfur was uniformly infiltrated into MSUF-C pores by a chemical solution deposition method (MSUF-C/S CSD) and the amount of sulfur loading was achieved as high as 73% thanks to the large pore volume with the CSD approach. MSUF-C/S CSD showed a high capacity (889 mAh/g after 100 cycles at 0.2 C), an improved rate capability (879 mAh/g at 1C and 420 mAh/g at 2C), and a good capacity retention with a fade rate of 0.16% per cycle over 100 cycles.</jats:p
Mg-doped Na[Ni1/3Fe1/3Mn1/3]O-2 with enhanced cycle stability as a cathode material for sodium-ion batteries
No full textO3-type Na[Ni1/3Fe1/3Mn1/3]O2 (NaNFM) is considered as a promising cathode material for sodium-ion batteries; however, its poor cycling stability is still a concern. In this study, we discuss the structural, surface and electrochemical properties of Mg-doped NaMgx[Ni1/3Fe1/3Mn1/3]1–xO2 materials and their enhanced cycling performance. The variations of the lattice parameters by substitution of Mg ion and its uniform distribution on the particles are confirmed using X-ray diffraction and transmission electron microscopy. The optimized NaMg0.05[Ni1/3Fe1/3Mn1/3]0.95O2 delivers a discharge capacity of ~120 mAh g−1 and has a diffusion coefficient of Na ranging from 6.5 × 10−13 to 2.7 × 10−10 cm2 s−1. In particular, it shows a relatively high discharge capacity of 42 mAh g−1 even at a high current density of 1200 mA g−1 and exhibits considerably enhanced cycling stability (77% capacity retention after 50 cycles), compared with that of the undoped NaNFM (40%). Based on structural and electrochemical analyses, it is suggested that Mg doping can effectively suppress the irreversible structural degradation and induce more reversible phase transitions; this results in a more stable cycling performance of the Mg-doped NaNFM than that of undoped NaNFM. © 2020 Elsevier Masson SAS1
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