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91.
面对仓促巨变的亚洲城市的严峻现实,设计者,包括建筑师、规划师和艺术家们,试图将个体的主张有效的介入城市生活,应对复杂的城市问题。作为2002上海双年展的策展人,作者介绍了由她推荐的十个艺术家和建筑师的作品。  相似文献   
92.
Ferroptosis, a term first proposed in 2012, is iron-dependent, non-apoptotic regulatory cell death induced by erastin. Ferroptosis was originally discovered during synthetic lethal screening for drugs sensitive to RAS mutant cells, and is closely related to synthetic lethality. Ferroptosis sensitizes cancer stem cells and tumors that undergo epithelial−mesenchymal transition and are resistant to anticancer drugs or targeted therapy. Therefore, ferroptosis-inducing molecules are attractive new research targets. In contrast, synthetic lethal strategies approach mechanisms and genetic abnormalities that cannot be directly targeted by conventional therapeutic strategies, such as RAS mutations, hypoxia, and abnormalities in the metabolic environment. They also target the environment and conditions specific to malignant cells, have a low toxicity to normal cells, and can be used in combination with known drugs to produce new ones. However, the concept of synthetic lethality has not been widely adopted with ferroptosis. In this review, we surveyed the literature on ferroptosis-related factors and synthetic lethality to examine the potential therapeutic targets in ferroptosis-related molecules, focusing on factors related to synthetic lethality, discovery methods, clinical application stages, and issues in drug discovery.  相似文献   
93.
94.
Eutectoid transformations accompanied by ordering   总被引:1,自引:0,他引:1  
Eutectoid transformations accompanied by ordering, unlike ordinary ones, proceed through non-pearlitic modes of transformations. Eutectoid invariants are classified into two categories in binary systems. The eutectoid invariant of A3()→D019(2) + L10(γ) in the Ti-Al binary system belongs to the first category, in which one product phase has an ordered structure of a parent phase. Its transformation product exhibits a γ/2 lamellar structure consisting of nearly perfectly aligned alternate lamellae of γ and 2, which is formed by precipitation of γ plates in either or 2 matrix with the Blackburn orientation relationship. The eutectoid invariant of A1(γ)→D022(γ″) + L12(γ′) in the Ni3V-Ni3Al pseudo-binary system is an example of the second category, in which both product phases have different ordered structures of a parent phase. The transformation of a 75Ni-18V-7Al alloy results in a ‘checkerboard’ pattern consisting of a periodic array of columns of γ′ and two γ″ orientation variants, which are formed by phase separation simultaneous with ordering.  相似文献   
95.
The paper reviewed the previous microgravity experiment using Chinese recovery satellite, the in-situ measurement of composition profile in the solution by X-ray penetration method and homogeneous growth of InGaSb by temperature freezing method under terrestrial condition for making clear the effect of gravity on the growth of InGaSb ternary alloy semiconductor crystals. The previous experimental results showed that the shape of solid/liquid interfaces and composition profile in the solution were significantly affected by gravity. Based on the previous microgravity experimental results, experimental conditions were investigated to grow homogeneous In xGa 1?xSb with higher indium composition at Chinese recovery satellite SJ-10 in near future.  相似文献   
96.
We performed high-field magnetization measurements, M(H), on the Ni5(TeO3)4Br2 by using a pulse magnet. The Ni2+ ions (S = 1) of this compound form a two dimensional distorted spin frustrated system (distorted kagome lattice), and undergo a Neel transition at T N ~29 K, due to the anisotropy. Below T N , a complex spin arrangement which contains ten spin sub-lattices was suggested by neutron scattering and electron spin resonance studies. We observed a step-like transition at H c ~11 T when T<T N . By contrast, at T>T N , the field-dependent magnetization curves behaved like a straight line. The H c is close to those obtained by previous spin resonance studies of Ni5(TeO3)4Br2 and Ni5(TeO3)4Cl2 in which a spin-flop-like transition was proposed to explain the field-dependent resonance spectra. Interestingly, the observed change in magnetization (ΔM) at H c corresponds to nearly one-half of the magnetic moment of Ni2+ ion, suggesting that the observed step-like behavior possibly corresponds to a spin-flip-like transition (i.e. from antiferromagnetic state to ferrimagnetic state). In addition, in the high-field region (H>H c ), the M(H) curves did not show plateau behavior, but exhibited the straight lines having finite slopes without any sign of saturation up to 55 T.  相似文献   
97.
Negative-ion fragmentation of N-glycans has been proven to be more informative than that of positive-ion. In particular, it defines structural features such as the specific composition of the two antennae and the location of fucose. However, negative-ion formation of neutral N-glycans by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) remains a challenging task, and the detection limit of N-glycans in negative-ion mode is merely at the subpicomole level. Thus, practical applications are limited. In this study, combinations of five liquid matrices and nine anions were used to ionize N-glycans as anionic adducts, and their performances for sensitive analyses were evaluated. The best results were obtained with anion-doped liquid matrix G(3)CA, which consists of p-coumaric acid and 1,1,3,3-tetramethylguanidine; the detection limits of anion adducted N-glycans were 1 fmol/well for NO(3)(-), and 100 amol/well for BF(4)(-). Negative-ion MS(2) spectra of 1 fmol N-glycans were successfully acquired with a sufficient signal-to-noise ratio and were quite useful for MS-based structural determination. The anion-doped G(3)CA matrix opens the way for sensitive and rapid analysis of neutral N-glycans in negative-ion MALDI at a low femtomole level.  相似文献   
98.
We constructed a novel bacterial genome detection system using zinc finger protein (ZF) fused with firefly luciferase (ZF-luciferase). Taking advantage of the direct recognition of double-stranded DNA (dsDNA) by ZF, we previously constructed bacterial genome detection systems that did not require dehybridization processes. To detect polymerase chain reaction (PCR) products rapidly and with a high sensitivity, we constructed two kinds of ZF-luciferase, Sp1-fused luciferase (Sp1-luciferase), and Zif268-fused luciferase (Zif268-luciferase). ZF-luciferase not only maintains luciferase activity but also shows dsDNA-binding ability and specificity. Furthermore, we succeeded in the detection of 10 copies of the genome of Legionella pneumophila and Escherichia coli O157. ZF-luciferase would be a useful tool for highly sensitive detection of pathogenic bacterial genome.  相似文献   
99.
We report a new application of affinity capture-elution electrospray mass spectrometry (ACESI-MS) to assay the enzymes phosphomannomutase (PMM) and phosphomannose isomerase (PMI), which when deficient cause congenital disorders of glycosylation CDG-type Ia and type Ib, respectively. The novel feature of this mass-spectrometry-based assay is that it allows one to distinguish and quantify enzymatic products that are isomeric with their substrates that are present simultaneously in complex mixtures, such as cultured human cell homogenates. This is achieved by coupled assays in which the PMM and PMI primary products are in vitro subjected to another enzymatic reaction with yeast transketolase that changes the mass of the products to be detected by mass spectrometry. The affinity purification procedure is fully automated, and the mass spectrometric analysis is multiplexed in a fashion that is suitable for high-throughput applications.  相似文献   
100.
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