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Long-term data from a small mammal community reveal loss of diversity and potential effects of local climate change

Current Zoology 2017年第5期63卷 515-523页

作者： Simone SANTORO Cristina SANCHEZ-SUAREZ Carlos Rouco L. Javier PALOMO M. Carmen FERNANDEZ Maura B. KUFNER Sacramento MORENO Ethology and Biodiversity Conservation Department DoSana Biological Station-CSIC Americo Vespucio s/n Seville 41092 Spain Departamento de Zoologfa Campus de Rabanales Universidad de Cordoba Cordoba 14071 Spain Wildlife Ecology and Management Team Private Bag 1930 Dunedin 9054 New Zealand Departamento de Biologia Animal Universidad de Malaga Malaga 29071 Spain Diego de 0norato 67 Barrio Uritorco Cordoba 5003 Argentina

Climate change affects distribution and persistence of species. However, forecasting species＇ re-sponses to these changes requires long-term data series that are often lacking in ecological *** used 15 years of small mammal trapping data collected between 1978 and 2015 in 3 areas atDoSana National Park （southwest Spain） to （i） describe changes in species composition and （ii） test theassociation between local climate conditions and size of small mammal populations. Overall, 5 specieswere captured： wood mouse Apodemus sylvaticus, algerian mouse Mus spretus, greater white-toothed shrew Crocidura russula, garden dormouse Eliomys quercinus, and black rat Rattus rattus. Thetemporal pattern in the proportion of captures of each species suggests that the small mammal diver-sity declined with time. Although the larger species （e.g., E. quercinus）, better adapted to colder cli-mate, have disappeared from our trapping records, M. spretus, a small species inhabiting southwestEurope and the Mediterranean coast of Africa, currently is almost the only trapped species. We used 2-level hierarchical models to separate changes in abundance from changes in probability of captureusing records of A. sylvaticus in all 3 areas and of Mo spretus in 1. We found that heavy rainfall and lowtemperatures were positively related to abundance of A. sylvaticus, and that the number of extremelyhot days was negatively related to abundance of M. spretus. Despite other mechanisms are likely to beinvolved, our findings support the importance of climate for the distribution and persistence of thesespecies and raise conservation concerns about potential cascading effects in the Donana ecosystem.

关键词： climate change, count data, N-mixture models, rodents, spain.

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Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern Nova Scotia, Canada

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Science China Earth Sciences 2006年第3期49卷 283-294页

作者： CHENG Qiuming1,2 1. State Key Lab of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China 2. Department of Earth and Space Science and Engineering, Department of Geography, York University, 4700 Keele Street, Toronto, Ontario, M3J 1P3, Canada 1. State Key Lab of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. Department of Earth and Space Science and Engineering Department of Geography York University 4700 Keele Street Toronto Ontario M3J 1P3 Canada

Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova Scotia, Canada. The results have shown that the values of uranium (U), thorium (Th) and potassium (K) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios U/K and U/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for U, Th, K, U/Th and U/K consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIS.

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Temporal and spatial rupture process of the great Kunlun Mountain Pass earthquake of November 14,2001 from the GDSN long period waveform data

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Science China Earth Sciences 2005年第1期48卷 112-122页

作者： XU Lisheng CHEN Yuntai Institute of Geophysics China Seismological Bureau Beijing 100081 China Institute of Geophysics China Seismological Bureau Beijing 100081 China

The temporal and spatial rupture process of the 14 November 2001 Kunlun Mountain Pass earthquake (KMPE) is obtained by inverting the high signal-to-noise-ratio P-waveform data of vertical components of 20 stations with epicentral distances less than 90°, which are of Global Digital Seismogragh Network (GDSN). The inverted results indicate that the KMPE consists of 3 sub-events. The rupture of the first sub-event initiated at the instrumental epicenter (35.97°N,90.59°E) and then propagated both westwards and eastwards, extending 140 km westwards at the speed of 4.0 km/s and 80 km eastwards at the speed of 2.2 km/s, which appeared to be an asymmetrical bilateral rupture dominantly from east to west. This sub-event formed a 220-km-long fault. Fifty-two seconds after initiation of the first sub-event, at which time the first sub-event was not over but in its healing phase, the rupture of the second sub-event initiated 220 km west of the epicenter and propagated both westwards and eastwards, extending 50 km westwards at the speed of 2.2 km/s and 70 km eastwards at the speed of 5.8 km/s, which appeared to be an asymmetrical bilateral rupture dominantly from west to east. The secondsub-event formed a 120-km-long fault. The second sub-event fused with the first sub-event 140km west to the epicenter right 12 s after its initiation. Fifty-six seconds after initiation of the first sub-event, at which time the first sub-event was getting close to the end of its healing phase, the rupture of the third sub-event initiated 220 km east of the epicenter and propagated both westwards and eastwards, extending 140 km westwards at the speed of 4.0 km/s and 130 km eastwards at the speed of 3.7 km/s, which appeared to be nearly an bilateral rupture. This sub-event formed a 270-km-long fault. The third sub-event fused with the first sub-event 80 km east of the epicenter right 36 s after its initiation. Afterwards, the source process of the KMPE was dominated by the slip after fusion of the

关键词： long-period waveform data, temporal and spatial rupture process, rupture fusion.

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LAD estimation for nonlinear regression models with randomly censored data

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Science China Mathematics 2005年第7期48卷 880-897页

作者： ZHOU Xiuqing WANG Jinde School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China Department of Mathematics Nanjing University Nanjing 210093 China Department of Mathematics Nanjing University Nanjing 210093 China

The least absolute deviations (LAD) estimation for nonlinear regression models with randomly censored data is studied and the asymptotic properties of LAD estimators such as consistency, boundedness in probability and asymptotic normality are established. Simulation results show that for the problems with censored data, LAD estimation performs much more robustly than the least squares estimation.

关键词： randomly censored data, nonlinear regression model, LAD estimator, asymptotic normality.

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Inversion of near-field waveform data for earthquake source rupture process(Ⅱ):Inversion of Chi Chi earthquake source,20 September,1999,Taiwan

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Science China Earth Sciences 2006年第3期49卷 272-282页

作者： ZHOU Shiyong CHEN Xiaofei Department of Geophysics Peking University Beijing 100871 China Department of Geophysics Peking University Beijing 100871 China

The new inversion algorithm developed based on the recent progress in thenonlinear programming study by us is used to invert the earthquake source process of Chi Chiearthquake M_w7.6, 20 Semptember,1999, Taiwan. A curve fault model is constructed in our inversionto make the fault model close to the real rupturing fault to reduce the influence from thediscrepancy between the constructed fault model and the real rupturing fault. The results show that(1) the rupture process of the Chi Chi earthquake source lasted about 32 seconds and the mainfaulting occurred between 6th to 21st second after the start of the ruptures and the high slip areawere mainly located at the northern segment of the fault. (2) The slip was dominated by thrustfaulting. The average rake angle was 64.5°, which was very consistent with those inverted by USGS,Harvard and CWB (Central Weather Bureau of Taiwan). The amount of the moment inverted in this paperwas 7.76x10^(20) NM, which was a slightly bigger than those inverted by USGS and Harvard. (3) Aclear nucleation step existed in the source faulting process and it lasted about 6 seconds. Themoment release rate accelerated obviously at the end of the nucleation step. The faulting startedfrom the southern segment and mainly occurred at the northern segment after 10 seconds. At the endof this paper, we analyzed the reliability of the inversion result via comparing with the GPSobservations and discussed its scientific signification.

关键词： Chi Chi earthquake, source rupture process, waveform inversion, near-source data, source mechanism.

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Iterative weighted partial spline least squares estimation in semiparametric modeling of longitudinal data

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Science China Mathematics 2003年第5期46卷 724-735页

作者：孙孝前尤进红 Department of Mathematics Huaiyin Teachers College Huaian 223001 China Department of Statistics University of Missouri-Columbia Columbia MO 65211 USA Department of Mathematics and Statistics University of Regina Regina Saskatchewan Canada S4S 0A2

In this paper we consider the estimating problem of a semiparametric regression modelling whenthe data are longitudinal. An iterative weighted partial spline least squares estimator (IWPSLSE) for the para-metric component is proposed which is more efficient than the weighted partial spline least squares estimator(WPSLSE) with weights constructed by using the within-group partial spline least squares residuals in the senseof asymptotic variance. The asymptotic normality of this IWPSLSE is established. An adaptive procedure ispresented which ensures that the iterative process stops after a finite number of iterations and produces anestimator asymptotically equivalent to the best estimator that can be obtained by using the iterative proce-dure. These results are generalizations of those in heteroscedastic linear model to the case of semiparametric regression.

关键词： semiparametric modelling, longitudinal data, iterative weighted partial spline leastsquares estimator (IWPSLSE), asymptotic normality.

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An adaptive FEC to protect RoHC and UDP-Lite H.264 video critical data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 910-918页

作者： CHEN Zhi-kui Networks and System Communications Regional Computer Center University of Stuttgart Stuttgart 70550 Germany

This paper describes how to use an Adaptive Forward Error Correction (AFEC) algorithm to efficiently protect the critical data areas of compressed headers and UDP-Lite packets for data transport in a radio link layer of a wireless connection. Augmented with RoHC and UDP-Lite, for H.264 video transmissions over wireless channels in a heterogeneous wired-wireless environment, the erroneous packet payloads can be useful and better able to cope with lost packets (native UDP case), by adopting some of the erasure and error resilient modes in H.264. The context transfer during inter/intra handover is also discussed. Simu- lations demonstrated that the proposed scenario significantly improves the PSNR performance and video quality.

关键词： Adaptive Forward Error Correction (AFEC), H.264, RoHC, UDP-Lite, UMTS, Bluetooth, Critical data, ErroneousSDU

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Effects of subsampling on characteristics of RNA-seq data from triple-negative breast cancer patients

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Chinese Journal of Cancer 2015年第10期34卷 427-438页

作者： Alexey Stupnikov Galina V Glazko Frank Emmert-Streib Computational Biology and Machine Learning Laboratory Faculty of MedicineHealth and Life SciencesSchool of MedicineDentistry and Biomedical SciencesCenter for Cancer Research and Cell BiologyQueen's University Belfast Division of Biomedical Informatics University of Arkansas for Medical Sciences Computational Medicine and Statistical Learning Laboratory Department of Signal ProcessingTampere University of Technology

Background:data from RNA-seq experiments provide a wealth of information about the transcriptome of an ***,the analysis of such data is very *** this study,we aimed to establish robust analysis procedures that can be used in clinical ***:We studied RNA-seq data from triple-negative breast cancer ***,we investigated the subsampling of RNA-seq ***:The main results of our investigations are as follows:(1) the subsampling of RNA-seq data gave biologically realistic simulations of sequencing experiments with smaller sequencing depth but not direct scaling of count matrices;(2) the saturation of results required an average sequencing depth larger than 32 million reads and an individual sequencing depth larger than 46 million reads;and(3) for an abrogated feature selection,higher moments of the distribution of all expressed genes had a higher sensitivity for signal detection than the corresponding mean ***:Our results reveal important characteristics of RNA-seq data that must be understood before one can apply such an approach to translational medicine.

关键词： RNA-seq data, Computational genomics, Statistical robustness, High-dimensional biology,Triple-negative breast cancer

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Motion estimation in wide band synthetic aperture sonar based on the raw echo data using the method of displaced phase center antenna

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声学技术 2003年第z1期22卷 56-59页

作者： JIANG Xiaokui, SUN Chao (Member, IEEE), FANG Jie (Institute of Acoustic Engineering, Northwestern Polytechnical University, Xi’an 710072, China) Institute of Acoustic Engineering Northwestern Polytechnical University Xi'an 710072 China

Phase errors in synthetic aperture sonar (SAS) imaging must be reduced to less than one eighth of a wavelength so as to avoid image destruction. Most of the phase errors occur as a result of platform motion errors, for example, sway yaw and surge that are the most important error sources. The phase error of a wide band synthetic aperture sonar is modeled and solutions to sway yaw and surge motion estimation based on the raw sonar echo data with a Displaced Phase Center Antenna (DPCA) method are proposed and their implementations are detailed in this paper. It is shown that the sway estimates can be obtained from the correlation lag and phase difference between the returns at coincident phase centers. An estimate of yaw is also possible if such a technique is applied to more than one overlapping phase center positions. Surge estimates can be obtained by identifying pairs of phase centers with a maximum correlation coefficient. The method works only if the platform velocity is low enough such that a number of phase centers from adjacent pings overlap.

关键词： sonar, synthetic aperture sonar (SAS), motion estimation, raw data, DPCA.

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Convergence rates of MLE in a partly linear model

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Science China Mathematics 2002年第11期45卷 1398-1407页

作者：薛宏旗 1. Department of Mathematics Graduate School Chinese Academy of Sciences 100039 Beijing China

This paper considers the estimation for a partly linear model with case 1 interval censored *** assume that the error distribution belongs to a known family of scale distributions with an unknown scaleparameter. The sieve maximum likelihood estimator (MLE) for the model's parameter is shown to be stronglyconsistent, and the convergence rate of the estimator is obtained and discussed.

关键词： partly linear model, case 1 interval censored data, sieve MLE, strong consistency,convergence rate.

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