基于GIS的重庆市秀山县白背飞虱空间格局分析

根据2003-2009年重庆市秀山县白背飞虱迁入前期的田间调查资料,应用地理信息系统(GIS)结合传统空间分布分析方法,研究了该县白背飞虱空间分布格局及其动态.结果表明:2003-2009年的白背飞虱种群在全县范围呈现明显的聚集分布格局;反向距离插值图显示,不同年度聚集中心和聚集程度是变化的.总的分布格局是,秀山县中部平坝地区的官桥、官庄、平凯镇发生较重,7年的调查数据中有4年的聚集中心位于此;而周边三沟两岔地区发生相对较轻,只有2007年聚集中心位于南部,2008年的聚集中心位于东部,2009年聚集中心位于北部和西部.     

The LKB1-like Kinase Elm1 Controls Septin Hourglass Assembly and Stability by Regulating Filament Pairing

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Dating of non-oak species in the United Kingdom historical buildings archive using stable oxygen isotopes

Stable oxygen isotope dendrochronology is an effective precision-dating method for fast grown, invariant (complacent) tree-rings and for trees growing in moist, temperate climatic regions where growth may not be strongly controlled by climate. The method works because trees preserve a strong common isotopic signal, from summer precipitation, and therefore do not need to be physiologically stressed to record a dating signal. This study explores the working hypothesis that whilst tree species may differ in their eco-physiology, leaf morphology and wood anatomy they will record an isotopic signal in their growth rings that is sufficiently similar to enable their precise dating against isotopic reference chronologies developed using dated oak tree rings from the same region. Modern and historical samples from six species (sweet chestnut, English elm, ash, alder, European beech and black poplar) were analysed and their oxygen isotopic variability was compared against an oak master chronology previously developed for central southern England. Whilst differences in the relative strength of the agreement between the different species and the master chronology are apparent, the potential for interspecies dating is demonstrated convincingly. The ability to date non-oak species using stable oxygen isotopes opens-up new opportunities for science-based archaeology and will improve understanding of a largely-unexplored, but significant part of the European historical buildings archive.     

Automatic Detection and Classification of Mammograms Using Improved Extreme Learning Machine with Deep Learning

Background and objectiveBreast cancer, the most intrusive form of cancer affecting women globally. Next to lung cancer, breast cancer is the one that provides a greater number of cancer deaths among women. In recent times, several intelligent methodologies were come into existence for building an effective detection and classification of such noxious type of cancer. For further improving the rate of early diagnosis and for increasing the life span of victims, optimistic light of research is essential in breast cancer classification. Accordingly, a new customized method of integrating the concept of deep learning with the extreme learning machine (ELM), which is optimized using a simple crow-search algorithm (ICS-ELM). Thus, to enhance the state-of-the-art workings, an improved deep feature-based crow-search optimized extreme learning machine is proposed for addressing the health-care problem. The paper pours a light-of-research on detecting the input mammograms as either normal or abnormal. Subsequently, it focuses on further classifying the type of abnormal severities i.e., benign type or malignant.Materials and methodsThe digital mammograms for this work are taken from the Curated Breast Imaging Subset of DDSM (CBIS-DDSM), Mammographic Image Analysis Society (MIAS), and INbreast datasets. Herein, the work employs 570 digital mammograms (250 normal, 200 benign and 120 malignant cases) from CBIS-DDSM dataset, 322 digital mammograms (207 normal, 64 benign and 51 malignant cases) from MIAS database and 179 full-field digital mammograms (66 normal, 56 benign and 57 malignant cases) from INbreast dataset for its evaluation. The work utilizes ResNet-18 based deep extracted features with proposed Improved Crow-Search Optimized Extreme Learning Machine (ICS-ELM) algorithm.ResultsThe proposed work is finally compared with the existing Support Vector Machines (RBF kernel), ELM, particle swarm optimization (PSO) optimized ELM, and crow-search optimized ELM, where the maximum overall classification accuracy is obtained for the proposed method with 97.193% for DDSM, 98.137% for MIAS and 98.266% for INbreast datasets, respectively.ConclusionThe obtained results reveal that the proposed Computer-Aided-Diagnosis (CAD) tool is robust for the automatic detection and classification of breast cancer.     

Somatic embryogenesis and plant regeneration from leaves of<Emphasis Type="Italic"> Ulmus minor</Emphasis> Mill.

Somatic embryogenesis from mature elm (Ulmus minor Mill.) in vitro-cloned material is possible. Embryogenic callus was obtained from leaves inoculated on two different MS-based media—one supplemented with 2.3 M 2,4-dichlorophenoxyacetic acid (I2) and the other supplemented with 1.1 M kinetin (I6). However, only leaves cultured on medium I6 produced somatic embryos, at the globular stage, when embryogenic callus was maintained in induction media. When embryogenic callus from medium I6 was transferred to basal medium, somatic embryos with green cotyledons were obtained. An average of 35.9% of these embryos converted easily into normal plants in conversion medium with 1% sucrose. Acclimatisation reached 39.7%, and this was not significantly different from a control group consisting of plants propagated by axillary buds. No morphological differences were observed between plants derived from somatic embryos and control plants. Also, no differences in ploidy were detected between the somatic embryo-derived plants and the mother plants.Abbreviations BA: Benzyladenine - C1, C2: Conversion media - 2,4-D: 2,4-Dichlorophenoxyacetic acid - Kn: Kinetin - NAA: -Naphthaleneacetic acid - PI: Propidium iodide - I2, I6: Induction media Communicated by D. Bartels     

Somatic embryogenesis in elm

We show that isolated zygotic embryos of Ulmus minor and U. glabra can produce embryogenic cultures provided they are isolated from immature seeds before storage proteins begin to accumulate. Rates of somatic embryogenesis were highest among zygotic embryos collected 6 weeks post-anthesis when they were at the midcotyledonary stage, were about 5 mm long and had a fresh weight of approx. 10 mg. At this time, induction was even possible in Murashige and Skoog basal medium with no plant growth regulators, but addition of 2,4-dichlorophenoxyacetic acid was necessary at earlier stages of zygotic development. In medium supplemented with benzyladenine (BA) only, no embryogenic induction was observed. The formation of callus was an essential step not only for the induction of embryogenic masses, but also for the maintenance of embryogenic competence through successive subculture of callus on induction media supplemented with 0.1 mg l(-1) BA. Nine embryogenic U. minor lines and 24 U. glabra lines have been maintained in this way for 3 years. However, conversion into plantlets has occurred only rarely.     

The internal microbial flora of the elm bark beetle, Scolytus scolytus, at all stages of its development

Adult Scolytus scolytus emerged from the pupal stage with sterile guts although microorganisms were present within the pupal body. Gut sterility was maintained in a large proportion of newly formed adults while they were boring out of an elm log. The adult gut microbial flora is mainly acquired during subsequent feeding. Differences were found between the microbial gut flora of both larvae and adult S. scolytus, and of both male and female beetles.     

A protocol for Ulmus minor Mill. micropropagation and acclimatization

Here we report the establishment of a simple protocol for the micropropagation and acclimatization of U. minor. Branches with dormant buds were collected from mature elms and sprouted in a greenhouse. Tip and node segments were used as starting material for in vitro proliferation in a medium (designated here as DKW1) already used for the micropropagation of a clone of the English Elm (U. procera SR4). In the first assay, in which explants from nine different trees were used, 88.5% of the tip segments produced new axillary shoots thus proving to be the best explant type. Afterwards, material from four different trees (F4, F7, F13, F14), that had the highest sprouting rate in the greenhouse, was used to test for genotype influence. F14 proved to be the best genotype in culture and it was used for all the subsequent experiments. Shoots from F14 were used to assay in vitro rooting using five DKW based media. Rooting percentages were high for all media and varied between 80% and 100%. For acclimatization two approaches were assayed: the use of previously rooted in vitro plants and the direct acclimatization of shoots from cultures in DKW1. After 6 weeks, 86.4% of the in vitro rooted plants were successfully acclimatized and a slightly higher value, 88.6%, was attained by direct acclimatization of shoots with thick stems and hard leaves. These results proved that there is no need for a previous in vitro rooting step and that direct acclimatization can effectively reduce time and costs. Thus U. minor micropropagation and acclimatization can be divided into only two steps: proliferation of shoots in DKW1 and direct acclimatization of these shoots in a sterile soil mixture.     

Aerobiological aspects of elm (Ulmus spp) in South-East Scotland in relation to elm decline from Dutch Elm disease (1976–1996)

Elms (Ulmus procera andU. glabra) have been devastated in the UK by Dutch Elm disease. Because of lower temperatures in Northern Britain, relative to Southern Britain, elms have survived. In spite of this, elms have declined markedly in South-east Scotland over the past 20 years. Tree data relating to this decline are presented, together with a pollen calendar for the genus in S.E. Scotland and a tentative forecast for the disappearance of these two species in the region.