264 resultados para Tomlin, Lily
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百合是重要的球根花卉,是世界五大切花之一。我国的百合野生资源丰富,但百合鲜切花生产与世界花卉大国相比仍然存在差距,优质的商品种球大量依靠进口,实现商品种球国产化能够促进百合鲜切花生产和农业经济发展。温度是影响百合生长发育最重要的因子之一,影响百合鳞茎发育,限制百合的分布区域。 百合鳞茎具有自然休眠的特性,低温处理是目前打破百合鳞茎休眠的最常用的方法。低温处理期间,鳞茎内发生复杂的反应,淀粉水解,鳞茎内的淀粉酶(α-淀粉酶和β-淀粉酶)活性增加,可溶性糖主要是蔗糖积累;可溶性蛋白质含量增加,游离氨基酸在鳞茎相对幼嫩的器官中集中;休眠解除期间脱落酸和玉米素核苷含量呈下降趋势,赤霉素含量呈上升趋势且活性增高,鳞茎各部位生长素都有上升,一些其他生长调节剂如Me-JA和多胺对解除百合鳞茎也有作用。低温处理期间,鳞茎内各种激素相互作用,共同调控鳞茎的休眠状态。利用低温处理打破百合鳞茎休眠的过程中,温度要求控制在稳定的范围内。利用冰箱低温处理打破百合鳞茎休眠的实验中,放入样品前冰箱内的温度在所设定温度±1℃范围内波动,且不同部位温度均匀;但冰箱内放入样品后,其内部不同部位的温度相差较大,表现为上部温度高,下部温度低,冰箱内部不同部位温度差异很大。 从百合资源在中国的分布看,华北地区的百合资源相对稀缺,温度是限制其生长的重要环境因子。新铁炮百合能够在炎热的华南地区露地栽培,将其在华北地区进行区域化露地栽培实验,对百合栽培应用推广,扩大栽培面积,降低运输成本,以及保证鲜切花质量有重要意义。通过气体交换测定的光合作用是对高温最敏感和综合的生理指标,可以在植物生长和生物量积累未发生明显变化之前揭示高温的影响。本研究通过人工气候箱,设定四个温度梯度:25℃,32℃,38℃,44℃,处理2h,通过测定新铁炮百合幼苗的光合特性研究其耐热程度、探讨可能的耐热机制。结果表明:净光合作用速率(Pn)在小于38℃时下降幅度不大,大于38℃后显著下降,随着处理温度的提高,气孔导度(Gs)呈下降的趋势,胞间二氧化碳浓度(Ci)则上升,而气孔限制值(Ls)下降。高温下,两品种叶片最小荧光(Fo)无明显变化,最大荧光(Fm)和光系统II(PSⅡ)最大光化学效率(Fv/Fm)下降程度较小;光下,PSⅡ实际光化学效率(ΦPSⅡ)呈下降趋势,44℃处理后显著下降;NPQ随处理温度的提高而上升;处理温度升高,SOD、APX、CAT、POD活力增强。研究表明新铁炮百合能够耐受32-38℃的高温;热胁迫下,叶片通过提高非光化猝灭和抗氧化酶活性两种机制来抵御高温胁迫。
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This paper describes a representation of the dynamics of human walking action for the purpose of person identification and classification by gait appearance. Our gait representation is based on simple features such as moments extracted from video silhouettes of human walking motion. We claim that our gait dynamics representation is rich enough for the task of recognition and classification. The use of our feature representation is demonstrated in the task of person recognition from video sequences of orthogonal views of people walking. We demonstrate the accuracy of recognition on gait video sequences collected over different days and times, and under varying lighting environments. In addition, preliminary results are shown on gender classification using our gait dynamics features.
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Passive monitoring of large sites typically requires coordination between multiple cameras, which in turn requires methods for automatically relating events between distributed cameras. This paper tackles the problem of self-calibration of multiple cameras which are very far apart, using feature correspondences to determine the camera geometry. The key problem is finding such correspondences. Since the camera geometry and photometric characteristics vary considerably between images, one cannot use brightness and/or proximity constraints. Instead we apply planar geometric constraints to moving objects in the scene in order to align the scene"s ground plane across multiple views. We do not assume synchronized cameras, and we show that enforcing geometric constraints enables us to align the tracking data in time. Once we have recovered the homography which aligns the planar structure in the scene, we can compute from the homography matrix the 3D position of the plane and the relative camera positions. This in turn enables us to recover a homography matrix which maps the images to an overhead view. We demonstrate this technique in two settings: a controlled lab setting where we test the effects of errors in internal camera calibration, and an uncontrolled, outdoor setting in which the full procedure is applied to external camera calibration and ground plane recovery. In spite of noise in the internal camera parameters and image data, the system successfully recovers both planar structure and relative camera positions in both settings.
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Purpose: To quantify decreases in health-related quality of life (HRQoL) for given deterioration in clinical measures of vision; to describe the shape of these relationships; and to test whether the gradients of these relationships change with duration of visual loss.
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The origin and evolution of venom proteins in helodermatid lizards were investigated by multidisciplinary techniques. Our analyses elucidated novel toxin types resultant from three unique domain-expression processes: 1) The first full-length sequences of lethal toxin isoforms (helofensins) revealed this toxin type to be constructed by an ancestral monodomain, monoproduct gene (beta-defensin) that underwent three tandem domain duplications to encode a tetradomain, monoproduct with a possible novel protein fold; 2) an ancestral monodomain gene (encoding a natriuretic peptide) was medially extended to become a pentadomain, pentaproduct through the additional encoding of four tandemly repeated proline-rich peptides (helokinestatins), with the five discrete peptides liberated from each other by posttranslational proteolysis; and 3) an ancestral multidomain, multiproduct gene belonging to the vasoactive intestinal peptide (VIP)/glucagon family being mutated to encode for a monodomain, monoproduct (exendins) followed by duplication and diversification into two variant classes (exendins 1 and 2 and exendins 3 and 4). Bioactivity characterization of exendin and helokinestatin elucidated variable cardioactivity between isoforms within each class. These results highlight the importance of utilizing evolutionary-based search strategies for biodiscovery and the virtually unexplored potential of lizard venoms in drug design and discovery.
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Venom has only been recently discovered to be a basal trait of the Anguimorpha lizards. Consequently, very little is known about the timings of toxin recruitment events, venom protein molecular evolution, or even the relative physical diversifications of the venom system itself. A multidisciplinary approach was used to examine the evolution across the full taxonomical range of this similar to 130 million-year-old clade. Analysis of cDNA libraries revealed complex venom transcriptomes. Most notably, three new cardioactive peptide toxin types were discovered (celestoxin, cholecystokinin, and YY peptides). The latter two represent additional examples of convergent use of genes in toxic arsenals, both having previously been documented as components of frog skin defensive chemical secretions. Two other novel venom gland-overexpressed modified versions of other protein frameworks were also recovered from the libraries (epididymal secretory protein and ribonuclease). Lectin, hyaluronidase, and veficolin toxin types were sequenced for the first time from lizard venoms and shown to be homologous to the snake venom forms. In contrast, phylogenetic analyses demonstrated that the lizard natriuretic peptide toxins were recruited independently of the form in snake venoms. The de novo evolution of helokinestatin peptide toxin encoding do-mains within the lizard venom natriuretic gene was revealed to be exclusive to the helodermatid/anguid subclade. New isoforms were sequenced for cysteine-rich secretory protein, kallikrein, and phospholipase A 2 toxins. Venom gland morphological analysis revealed extensive evolutionary tinkering. Anguid glands are characterized by thin capsules and mixed glands, serous at the bottom of the lobule and mucous toward the apex. Twice, independently this arrangement was segregated into specialized serous protein-secreting glands with thick capsules with the mucous lobules now distinct (Heloderma and the Lanthanotus/Varanus clade). The results obtained highlight the importance of utilizing evolution-based search strategies for biodiscovery and emphasize the largely untapped drug design and development potential of lizard venoms. Molecular & Cellular Proteomics 9:2369-2390, 2010.
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Pollen tube growth is dependent on a dynamic actin cytoskeleton, suggesting that actin-regulating proteins are involved. We have examined the regulation of the lily pollen-specific actin-depolymerizing factor (ADF) LIADF1. Its actin binding and depolymerizing activity is pH sensitive, inhibited by certain phosphoinositides, but not controlled by phosphorylation. Compared with its F-actin binding properties, its low activity in depolymerization assays has been used to explain why pollen ADF decorates F-actin in pollen grains. This low activity is incompatible with a role in increasing actin dynamics necessary to promote pollen tube growth. We have identified a plant homolog of actin-interacting protein, AIP1, which enhances the depolymerization of F-actin in the presence of LIADF1 by similar to60%. Both pollen ADF and pollen AIP1 bind F-actin in pollen grains but are mainly cytoplasmic in pollen tubes. Our results suggest that together these proteins remodel actin filaments as pollen grains enter and exit dormancy.
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We have examined the interaction of recombinant lily pollen ADF, LIADF1, with actin and found that whilst it bound both G- and F-actin, it had a much smaller effect on the polymerization and depolymerization rate constants than the maize vegetative ADF, ZmADF3. An antiserum specific to pollen ADF, antipADF, was raised and used to localize pollen ADF in daffodil - a plant in which massive reorganizations of the actin cytoskeleton have been seen to occur as pollen enters and exits dormancy. We show, for the first time, an ADF decorating F-actin in cells that did not result from artificial increase in ADF concentration. In dehydrated pollen this ADF:actin array is replaced by actin:ADF rodlets and aggregates of actin, which presumably act as a storage form of actin during dormancy. In germinated pollen ADF has no specific localization, except when an adhesion is made at the tip where actin and ADF now co-localize. These activities of pollen ADF are discussed with reference to the activities of ZmADF3 and other members of the ADF/cofilin group of proteins.
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This study sought to determine whether 80-lead body surface potential mapping (BSPM) would improve detection of acute myocardial infarction (AMI) and occluded culprit artery in patients presenting with ST-segment depression (STD) only on 12-lead ECG.
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Tese de doutoramento, Biologia (Biologia do Desenvolvimento), Universidade de Lisboa, Faculdade de Ciências, 2015
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The St. Catharines and District Council of Women was founded in 1918 and elected as its first president, Mary Malcolmson. In 1910 Mrs. Malcolmson founded North America’s first Girl Guide Association in St. Catharines. The aim of the organization was to work for the betterment of conditions pertaining to the family, community and state. The Council is an umbrella group for various women’s organizations in the area and functions at the provincial, national and international levels and is associated with the United Nations. In the early years the National Council brought in the Victorian Order of Nurses (VON) and started the Women’s Canadian Club. The St. Catharines Council initiated Child Welfare Centres in local churches that grew into the Well Baby Clinics. Women were encouraged to take political office and join committees with much success. In 1929, “Shop at Home” exhibition became an annual event highlighting the services of local merchants. Money raised by the Council was donated to local charities and in 1930 the Council assisted the local Armenian community in building the first Armenian Church in Canada. In 1932 the Council started the Maternal Welfare programme in which Mothers’ Meetings were held weekly with various speakers from the Public Health Department. In 1975 to celebrate International Women’s Year and the 1976 Centennial of the City of St. Catharines, the group sponsored the book Women of Action, 1876-1976, written by two of its members, Lily M. Bell and Kathleen E. Bray. Some time after 1976 the name of the organization changed from St. Catharines Local Council of Women to St. Catharines and District Council of Women. Today the organization functions as an advocacy and educational group.
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Letter to W.D. Woodruff from Langley and Rymer, Jobbers in Masonry, St. Catharines regarding tenders for the proposed lily pond. This is accompanied by an envelope. May 9, 1916.
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Letter to T. H. Wiley from J.J. Nichols and Sons, Mason Contractors and Plasterers, St. Catharines regarding tenders for the proposed lily pond, May 12, 1916.
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Letter to Mr. Welland D. Woodruff from Thos. Wiley, Architect, St. Catharines regarding tenders for the proposed lily pond, May 17, 1916.