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1. chinaXiv:201908.00118 [pdf]

Five new species of Arvicolinae and Myospalacinae from the Late Pliocene−Early Pleistocene of Nihewan Basin

ZHENG Shao-Hua; ZHANG Ying-Qi;  CUI Ning
Subjects: Biology >> Zoology

The Nihewan Basin has been well known for its Cezonoic fossiliferous fluviolacustrine deposits and paleolithic sites for almost a century. There have been considerable research efforts devoted to the understanding of the geology, chronology, and stratigraphy of this complex of sedimentary body. The current fundamental problem lies in the chronological aspect of the Nihewan Beds. Arvicolinae and Myospalacinae are two groups of rodents characterized by rapid evolutionary rates and quantifiable evolutionary trends, and hence particularly helpful in Late Cenozoic biostratigraphic correlations. Therefore, we briefly describe three new species of Arvicolinae and two new species of Myospalacinae that mainly came from the selected sections in the Nihewan Basin. Hopefully, they would contribute towards the establishment of the biostratigraphic framework of the Nihewan Basin and provide new evidence on the chronological understanding of the Nihewan Beds from an evolutionary point of view.

submitted time 2019-08-26 From cooperative journals:《古脊椎动物学报》 Hits5653Downloads272 Comment 0

2. chinaXiv:201804.01251 [pdf]

Fossil gibbons (Mammalia, Hylobatidae) from the Pleistocene of Chongzuo, Guangxi Zhuang Autonomous Region, China

ZHANG Ying-Qi; JIN Chang-Zhu; WANG Yuan; Alejandra ORTIZ; HE Kai; Terry HARRISON
Subjects: Geosciences >> Geology

Recent fieldwork at Pleistocene cave sites in the Chongzuo area in Guangxi Zhuang Autonomous Region has yielded 33 isolated teeth of fossil hylobatids. Comparisons indicate that the teeth can all be referred to a single species of Nomascus, but the material is insufficient to assign it to a particular species. The molars are slightly larger on average than those of extant species of Nomascus, but unlike contemporary great apes from the Pleistocene of southern China, the hylobatids do not seem to have undergone a change in dental size through time. Nomascus is not present in the Chongzuo area today, but historical records indicate that the genus may have been widely distributed across southern China in the recent past.

submitted time 2018-04-04 From cooperative journals:《古脊椎动物学报》 Hits4259Downloads706 Comment 0

3. chinaXiv:201711.02434 [pdf]

A Machine Learning Assisted, Label-free, Non-invasive Approach for Somatic Reprogramming inInduced Pluripotent Stem Cell Colony Formation Detection and Prediction

Fan, K (Fan, Ke); Zhang, S (Zhang, Sheng); Zhang, Y (Zhang, Ying); Lu, J (Lu, Jun); Holcombe, M (Holcombe, Mike); Zhang, X (Zhang, Xiao)
Subjects: Biology >> Ecology

During cellular reprogramming, the mesenchymal-to-epithelial transition is accompanied by changes in morphology, which occur prior to iPSC colony formation. The current approach for detecting morphological changes associated with reprogramming purely relies on human experiences, which involve intensive amounts of upfront training, human error with limited quality control and batch-to-batch variations. Here, we report a time-lapse-based bright-field imaging analysis system that allows us to implement a label-free, non-invasive approach to measure morphological dynamics. To automatically analyse and determine iPSC colony formation, a machine learning-based classification, segmentation, and statistical modelling system was developed to guide colony selection. The system can detect and monitor the earliest cellular texture changes after the induction of reprogramming in human somatic cells on day 7 from the 20-24 day process. Moreover, after determining the reprogramming process and iPSC colony formation quantitatively, a mathematical model was developed to statistically predict the best iPSC selection phase independent of any other resources. All the computational detection and prediction experiments were evaluated using avalidation dataset, and biological verification was performed. These algorithm-detected colonies show no significant differences (Pearson Coefficient) in terms of their biological features compared to the manually processed colonies using standard molecular approaches.

submitted time 2017-11-17 Hits321Downloads203 Comment 0

4. chinaXiv:201703.00308 [pdf]

Target brightness temperature simulation and analysis for the geostationary interferometric microwave sounder (GIMS)

Zhang, Ying; Liu, Hao; Wu, Ji; He, Jieying; Zhang, Cheng
Subjects: Geosciences >> Space Physics

Target brightness temperature maps can be used in geostationary interferometric microwave sounder (GIMS) system simulation. System simulation with accurate target brightness temperature maps can evaluate system performance in near real case and thus help adjust design parameters for the sensor before it is finally put into use. In this paper, method of simulating target brightness temperature using Weather Research and Forecasting Model and Radiative Transfer for TOVS (RTTOV) has been discussed. Target brightness temperature simulation results at oxygen absorption band and water-vapor absorption band have been presented. Some preliminary analyses of simulated brightness temperature for GIMS' observation have also been given.

submitted time 2017-03-10 Hits16176Downloads930 Comment 0

5. chinaXiv:201703.00298 [pdf]

A deblurring method for dynamic target observation of the geostationary interferometric microwave sounder (GIMS)

Zhang, Ying; Liu, Hao; Wu, Ji; Zhang, Cheng; He, Jieying
Subjects: Geosciences >> Space Physics

Brightness temperature change of observation target in one imaging period will introduce image blur to the retrieved image of geostationary interferometric microwave sounder (GIMS), which uses rotating circular array to realize time-sharing sampling other than snap-shot to reduce system complexity but meanwhile resulting in a relatively long imaging period. In this paper, an interpolation method utilizing time sequence of visibilities collected by time-sharing sampling is presented. The method is verified through a simulation system that simulates GIMS's observation process in viewing a series of near real case brightness temperature maps modeled by FNL/WRF/RTTOV method. Results show that the interpolation method can de-blur the image and reduce imaging error to the degree of snap-shot imaging. �2016 IEEE.

submitted time 2017-03-10 Hits1475Downloads515 Comment 0

6. chinaXiv:201703.00291 [pdf]

Analysis and simulation of GIMS observation on dynamic targets

Zhang, Ying; Liu, Hao; Wu, Ji; Zhang, Cheng; He, Jieying
Subjects: Geosciences >> Space Physics

Imaging period is an important consideration to geostationary interferometric microwave sounder (GIMS) when mapping fast changing target such as typhoon. GIMS simulation system with near real case observation target can evaluate system performance in different system configurations and thus help determine the optimal imaging period. In this paper, GIMS simulation system using MATLAB and near real case observation modeled by FNL/WRF/RTTOV method has been used to analyze the effect of imaging period on image quality. System simulation results for each frequency channel will be presented and analyses of imaging period's effect on image quality will also be given. �2016 IEEE.

submitted time 2017-03-10 Hits1399Downloads464 Comment 0

7. chinaXiv:201703.00287 [pdf]

Passive submillimeter-wave imaging demonstrated by a two-element interferometer

Han, Dong-Hao; Liu, Hao; Zhang, De-Hai; Meng, Jin; Zhao, Xin; Zhang, Ying; Wu, Ji
Subjects: Geosciences >> Space Physics

In this paper, an SMMW interferometric radiometer concept is demonstrated by a two-element interferometer with dedicated high accuracy SMMW devices. Point-source calibration method is introduced in order to reduce instrument errors. Interference fringes and point target images are presented by this SMMW interferometer. The linear phase error of the interference fringes is less than 2�and the angular resolution is better than 0.57� The measured performance characteristics of the two-element interferometer are consistent with the theoretical analysis. This interferometer demonstrates a new method for passive SMMW remote sensing. �2016, Science Press. All right reserved.

submitted time 2017-03-10 Hits983Downloads562 Comment 0

8. chinaXiv:201605.01244 [pdf]

Structural Insights into the Molecular Recognition between Cerebral Cavernous Malformation 2 and Mitogen-Activated Protein Kinase Kinase Kinase 3

Wang, Xiaoyan; Hou, Yanjie; Deng, Kai; Zhang, Ying; Wang, Da-Cheng; Ding, Jingjin; Wang, Xiaoyan; Deng, Kai
Subjects: Biology >> Biophysics >> Biochemistry & Molecular Biology

Cerebral cavernous malformation 2 (CCM2) functions as an adaptor protein implicated in various biological processes. By interacting with the mitogen-activated protein kinase MEKK3, CCM2 either mediates the activation of MEKK3 signaling in response to osmotic stress or negatively regulates MEKK3 signaling, which is important for normal cardiovascular development. However, the molecular basis governing CCM2-MEKK3 interaction is largely unknown. Here we report the crystal structure of the CCM2 C-terminal part (CCM2ct) containing both the five-helix domain (CCM2ct(s)) and the following C-terminal tail. The end of the C-terminal tail forms an isolated helix, which interacts intramolecularly with CCM2ct(s). By biochemical studies we identified the N-terminal amphiphilic helix of MEKK3 (MEKK3-n(helix)) as the essential structural element for CCM2ct binding. We further determined the crystal structure of CCM2ct(s)-MEKK3-n(helix) complex, in which MEKK3-n(helix) binds to the same site of CCM2ct(s) for CCM2ct intramolecular interaction. These findings build a structural framework for understanding CCM2ct-MEKK3 molecular recognition.

submitted time 2016-05-11 Hits587Downloads302 Comment 0

9. chinaXiv:201605.00283 [pdf]

TARGET BRIGHTNESS TEMPERATURE SIMULATION AND ANALYSIS FOR THE GEOSTATIONARY INTERFEROMETRIC MICROWAVE SOUNDER (GIMS)

Zhang, Ying; Liu, Hao; Wu, Ji; He, Jieying; Zhang, Cheng
Subjects: Geosciences >> Space Physics

Target brightness temperature maps can be used in geostationary interferometric microwave sounder (GIMS) system simulation. System simulation with accurate target brightness temperature maps can evaluate system performance in near real case and thus help adjust design parameters for the sensor before it is finally put into use. In this paper, method of simulating target brightness temperature using Weather Research and Forecasting Model and Radiative Transfer for TOVS (RTTOV) has been discussed. Target brightness temperature simulation results at oxygen absorption band and water-vapor absorption band have been presented. Some preliminary analyses of simulated brightness temperature for GIMS' observation have also been given.

submitted time 2016-05-03 Hits737Downloads451 Comment 0

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