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1. chinaXiv:202107.00011 [pdf]

Characterizations of compactness in fuzzy set spaces

Huan Huang
Subjects: Mathematics >> Mathematics (General)

In this paper, we mainly discuss characterizations of total boundedness, relative compactness and compactness in fuzzy set spaces.

submitted time 2021-07-22 Hits2227Downloads130 Comment 0

2. chinaXiv:202107.00008 [pdf]

GT198蛋白是抗癌化药和抗癌草药的靶点

庞峻峰; 高洁; 张立勇; Nahid F. Mivechi ; 柯蓝
Subjects: Medicine, Pharmacy >> Pharmacology

肿瘤血管生成是癌症的一个特征。一些抗血管生成的抗癌药物已被证明临床有疗效。我们之前的研究显示,在包括口腔癌在内的人类实体瘤中,GT198 蛋白(基因符号PSMC3IP,又称为Hop2)是一个诱导血管生成的癌蛋白。本研究结果表明,十几种临床抗癌化疗药物,和几种临床成功的抗癌草药,都能直接抑制GT198蛋白靶点。GT198是一个能与DNA结合的DNA修复蛋白。利用体外DNA结合法检测GT198活性,我们测试了129个美国NCI收集的临床抗癌化疗药物。发现体外直接抑制GT198的化药包括但不限于米托蒽醌、多柔比星(阿霉素)、紫杉醇、依托泊苷、放线菌素D和伊马替尼(格列卫)。紫杉醇和依托泊苷具有较高的结合亲和力,而多柔比星由于竞争性抑制GT198,具有较高的结合效力。由于GT198与DNA拓扑异构酶有蛋白序列同源性,而DNA拓扑异构酶是过去认为的药物靶点,因此,GT198蛋白很可能是个以前未被认知的药物新靶点。为了寻求更高效的GT198抑制剂,我们进一步测试了几种抗癌草药的提取物。发现具有高亲和力和高效力的阳性抑制草药都是临床上已经有成功历史的抗癌草药,包括牙买加的多香果(Allspice)、中国的皂角刺(Gleditsia sinensis L.),和厄瓜多尔的BIRM。我们使用有机化学方法对多香果进行了部分纯化,证明用GT198为靶标,以体外DNA结合法追踪测活,可以高效快速纯化天然产物。综上表明,此项研究揭示了GT198是多种抗癌化药的新靶点。这项研究还提供了一个鉴定化合物与纯化天然产物的优异药物靶标。特别关键的是,这项研究为快速分离高效低毒的抗癌中草药提供了绝佳机会。

submitted time 2021-07-12 Hits3301Downloads125 Comment 0

3. chinaXiv:202101.00003 [pdf]

On dark matter

Xian-Qiao Yu
Subjects: Physics >> The Physics of Elementary Particles and Fields

In this article, I shall propose a new theory of dark matter, in which I introduce a neutral primordial field, which is a new field beyond the standard model. All the standard model elementary particles are produced spontaneously from this field in the Big Bang epoch of the universe and then these produced elementary particles decayed or annihilated in the well-known standard model interactions. The relic of the primordial field appears in a form of vacuum energy can not only give naturally the correct abundance of dark matter in the present universe, but provide a natural solution to the cosmological constant problem as well. We find that the conventional methods of detecting dark matter either fail or have great difficulties to detect the remaining vacuum energy of the primordial field, and how to confirm the existence of the remaining energy of the universe's original energy in experiment is still an open problem.

submitted time 2021-06-29 Hits6786Downloads736 Comment 0

4. chinaXiv:201904.00075 [pdf]

A Possible Modified Dispersion Relation

胡锦文
Subjects: Physics >> Geophysics, Astronomy, and Astrophysics

本文引入了一个参量n来表征不同惯性系间光速的变化。为了满足众所周知的基本原理,又不违背一些可靠的实验结果,我们应该对n施加一些必要的约束。首先,重要的是,n的引入应该符合以下三个原则:(1)我们可以用一个规定的时钟同步来定义整个空间中的时间;(2)时间是均匀的,空间是各向同性的;(3)所有的惯性系统都是等价的,这是对狭义相对论(SR)思想的继承。在n的一些约束条件下,我们构造了一个满足惯性系对称性的一般坐标变换。近年来,许多理论都表现出对超高能量尺度下洛伦兹不变性的破坏的兴趣,例如量子引力,它暗示粒子的能量有一个有限值(称为普朗克能量),而不是从洛伦兹模型导出的无限值。因此我们构造一个n的表达式来描述洛伦兹模型的违逆。进一步,通过与著名的彩虹模型比较,我们发现本文推导的“最大能量”与彩虹模型假设的“最大能量”有一定的关系。

submitted time 2021-06-26 Hits21694Downloads1002 Comment 0

5. chinaXiv:202106.00106 [pdf]

A fragment of Argoland from East Gondwana in the NE Himalaya

Ji’en Zhang; Wenjiao Xiao; John Wakabayashi; Brian F Windley; Chunming Han
Subjects: Geosciences >> Geology

Previous studies have concluded that a Trans-Tethyan oceanic subduction zone existed prior collision of India-Eurasian plates, between which the ocean lacked intervening continental slivers. In contrast, we present first geological evidence of Early Cretaceous shortening and Late Jurassic alkali magmatism constraining that the Longzi block, an extensive (>450 km E-W by ca. 130 km N-S) tract of the NE Himalaya is such a continental sliver. The Longzi block records overturned south-vergent folds in Triassic to Lower Cretaceous strata intruded by 136-123 Ma mafic, dioritic, and dacite dikes, constraining Early Cretaceous shortening. The shortening demonstrates the NE Himalayan locating in a compressional setting, rather than an extensional Indian passive continental margin at that time. Triassic strata of NW Australian affinity and Late Jurassic rocks sourced from north India record pre-rifting history. Rifting evidence includes 152.8 Ma alkali intrusive rocks, a Late Jurassic unconformity, and rapid changes in sediment thickness and apparent water depth of deposition recorded in Upper Jurassic strata. The rifting event is coeval with 152-155 Ma oceanic crust in the NE Indian Ocean and a Late Jurassic submarine escarpment with 1200 m of sediments offshore of NW Australia. These data may reflect rifting of the westernmost Argoland continent in NE Himalaya from East Gondwana, followed by collision with a N-dipping Trans-Tethyan intra-oceanic subduction zone in the Early Cretaceous, long before terminal continent-continent collision. The Mesozoic rifting-collision in the Himalayan region unambiguously presents archipelagic paleogeography in eastern Neotethyan, which underwent Cenozoic two-stage Indian-Eurasian collisional processes.

submitted time 2021-06-24 Hits3576Downloads190 Comment 0

6. chinaXiv:201907.00003 [pdf]

Sub-parallel ridge-trench interaction and an alternative model for the Silurian-Devonian archipelago in Western Junggar and North-Central Tianshan in NW China

Zhang, Ji'en; Chen, Yichao; Xiao, Wenjiao; Wakabayashi, John; Windley, Brian F.; Yin, Jiyuan
Subjects: Geosciences >> Geology

Plate boundary evolution and interpreted paleogeography commonly involve the interaction between oceanic ridges and trenches. Western Junggar and Central-North Tianshan, NW China, have previously been regarded as independent orogens, but this model was challenged by the discovery of their similar tropic-subtropic coral assemblages and of Precambrian and Early Paleozoic clasts transmitted from the Central Tianshan in Early to Middle Paleozoic sediments in SW Junggar, suggesting they had been in contact by then. The presence of Late Silurian-Early Devonian adakitic rocks in northern SW Junggar was explained by slab roll-back, which required an active subducting slab in SW Junggar. However, this model is inconsistent with the cessation of arc magmatism immediately after the adakitic magmatism indicating there was no subduction in SW Junggar at those times. By re-evaluating the relevance of four diagnostic features of modern Californian ridge subduction, we propose a new model to explain the Late Silurian-Early Devonian orogenic framework of NW China in terms of sub-parallel ridge-trench interaction. The transmitted clasts from Central Tianshan in Early Paleozoic sediments in SW Junggar, at the same time as the Late Ordovician and Middle Silurian coral assemblages, and the complementary accretionary complex in SW Junggar and magmatic arc in Central Tianshan, are all contributary evidence for an Early Paleozoic subduction system. This subduction zone was intruded by two 446-380 Ma double magmatic belts: 1. A ridge subduction-generated adakitic gabbro-basalt-andesite-diorite-granite-rhyolite suite that intruded a 504-446 Ma accretionary complex in SW Junggar, and 2. a magmatic arc in Central Tianshan. A buoyant subducting ridge rifted and separated these magmatic belts resulting in the opening of a new 414-325 Ma ocean, which is preserved in OIB- and MORB-type ophiolites in SW Junggar and North Tianshan. These geological and geochemical relationships resemble those generated by oceanic spreading in the modern Gulf of California, which led to separation of magmatic belts in Baja California and mainland Mexico. The new ocean split the Central Tianshan magmatic arc from the Early Paleozoic Mt. Xiemisitai-Barleik-Mayile accretionary complex in SW Junggar, which changed to a new passive continental margin that led to deposition of Devonian shallow marine-terrestrial sediments, and to cessation of magmatism at 379-349 Ma. These features, including the Middle Paleozoic orogenic architecture and the geochemical properties of specific magmatic rocks, indicate the development of a Late Silurian-Early Devonian sub-parallel-to-trench ridge subduction. This model not only interprets phenomena mentioned in the above earlier models, but also reconciles unresolved spatial relationships between Western Junggar and the Tianshan. Subsequent closure of the new ocean and subduction of its ridge in the Late Paleozoic gave rise to the archipelagic framework that we see today in NW China. An analysis of worldwide examples of sub-parallel ridge-trench interaction demonstrates that a ridge can undergo multiple episodes of subduction before a terminal ocean closure. In this context our new tectonic model for the western Junggar and Tianshan regions may provide an improved understanding of the structure and evolution of ridge-subduction events in ancient orogenic belts.

submitted time 2021-06-22 Hits7082Downloads1215 Comment 0

7. chinaXiv:202105.00069 [pdf]

Copositivity for a class of fourth order symmetric tensors given by scalar dark matter

宋义生; 李旭东
Subjects: Mathematics >> Mathematical Physics

In this paper, we mainly discuss the copositivity of 4th order symmetric tensor defined by scalar dark matter stable under a $\mathbb{Z}_{3}$ discrete group, and obtain an analytically necessary and sufficient condition of the copositivity of such a class of tensors. Furthermore, this analytic expression may be used to verify the vacuum stability for $\mathbb{Z}_{3}$ scalar dark matter.

submitted time 2021-06-16 Hits3682Downloads288 Comment 0

8. chinaXiv:202106.00029 [pdf]

多模态学习诊断建模:知识结构和学习风格的双重诊断

詹沛达
Subjects: Psychology >> Psychological Measurement

在技术增强学习环境中,多模态数据为实现对知识结构和学习风格的双重诊断提供可能性。为实现对多模态数据的分析,本研究以融合分析题目作答精度、作答时间(RT)和视觉注视点数(FC)为例,基于联合-交叉负载建模法提出三个多模态学习诊断模型并与已有模型进行对比。研究结果表明:(1)融合分析比独立分析更适用于提供平行信息的多模态数据;(2)新模型可直接利用RT和FC中信息提高潜在能力或潜在属性的参数估计精度;(3)新模型可实现对知识结构和学习风格的双重诊断。总之,对多模态数据进行融合分析使得有关学习行为的诊断反馈更为全面和精准。

submitted time 2021-06-15 Hits3591Downloads327 Comment 0

9. chinaXiv:202104.00128 [pdf]

On the Dynamic Effect of Infinite Redshift Surface: Lorentz Factor Analysis Method

Jiayu NI; Yuan Tu
Subjects: Physics >> Geophysics, Astronomy, and Astrophysics

The generation of infinite redshift surface is due to the singularity of the Lorentz transformation, according to this fact, analyzing the singularity of the parameters in the Lorentz transform factor, which is named the Lorentz factor analysis method in this paper, can be used to research the dynamic effect of the infinite redshift surface. In this paper, the method is applied to the Reissner-Nordstrom and Kerr-Newman black hole spacetime, which finds that the infinite redshift surface will expand and contract with the observer's radial motion, and the corresponding equations are given clearly. A new proof of the inaccessibility of the time-like singularity in a charged black hole is given, and the inaccessibility of the time-like singularity is proved only related to the electrical nature, it has nothing to do with rotation. The study result of space-like quasi-circular motion observer shows that the infinite redshift surface is consistent with that of the static observer at infinity in this case. The minimum blueshift radius which is proposed in the study of the observer who escapes at the speed of light in normal spacetime, it makes a stronger constraint on black hole parameters than traditional condition. This is a possible reason why it is difficult to form an intermediate-mass black hole, discussion about it can be found at the end of the paper.

submitted time 2021-06-02 Hits4254Downloads312 Comment 0

10. chinaXiv:202105.00060 [pdf]

自我面孔识别的神经机制:基于fMRI研究的ALE元分析

那宇亭; 赵宇雯; 关丽丽
Subjects: Psychology >> Cognitive Psychology

自我面孔识别反映了个体通过自我与他人的区分识别出自我面孔的过程。本文采用ALE元分析的方法,对自我面孔识别的fMRI研究进行系统的定量分析,探究自我面孔识别的神经基础。结果显示,自我面孔识别的关键脑区包括顶上小叶、额中回、额下回、脑岛、梭状回、楔前叶和枕叶皮层。另外,自我面孔识别可能包括两个层面的加工过程:知觉层面的加工整合过程以及由知觉引发的评价和情绪反应过程。知觉加工整合涵盖了自我面孔识别的各个加工阶段,主要涉及枕叶、梭状回和楔前叶的功能;而评价加工及情绪反应过程则发生在自我面孔识别的中晚期,主要涉及顶上小叶、额中回、额下回及脑岛的功能。未来研究可结合时间和空间数据并关注脑区间的协同功能,考察与内感受的神经关联,开展临床研究并探索威胁信息的影响机制。

submitted time 2021-05-24 Hits4068Downloads424 Comment 0

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