Sample records for jacaranda mimosifolia tree

  1. [Experimental tolerance to boron of the plant species Nicotiana glauca, Jacaranda mimosifolia, Tecoma stans, Medicago sativa y Spinacea oleracea in Argentina].

    PubMed

    de Viana, Marta L; Albarracín Franco, Silvia

    2008-09-01

    The activity of boron industries is a punctual and diffuse source of air, soil and water pollution. Therefore, it is a priority to study possible ways of reducing this impact. A relatively new technology for reducing soil pollution is phytoremediation, which uses plants and associate microorganisms. The first step in phytoremediation is to detect tolerant plant species, which is the objective of this work. A laboratory experiment to assess the germination, survival and growth of different species at different boron concentrations was carried out following a factorial design with two factors: plant species and boron concentration. Boron concentrations were determined at the beginning and the end of the experiment, taking into account substrates with and without vegetation. We found significant differences for treatment, species and the interaction species*treatment. N. glauca, M. sativa and J. mimosifolia were the most tolerant species. The other species had a decrease in the response variables, with the concentration of the pollutant. All the species had a low survival at the highest boron concentration. The reduction in boron concentration at the end of the experiment was higher in the 30 ppm treatment with M. sativa and the lower was registered in the 20 ppm treatment with J. mimosifolia and in 30 ppm with T. stans and S. oleraceae. We conclude that N. glauca, M. sativa and J. mimosifolia can be considered in remediation plans. PMID:19419027

  2. Potential anticancer agents. IV. Constituents of Jacaranda caucana Pittier (Bignoniaceae).

    PubMed

    Ogura, M; Cordell, G A; Farnsworth, R

    1977-01-01

    An aqueous ethanol extract of Jacaranda caucana Pittier (Bignoniaceae) showed in vivo antitumor activity against the P-388 lymphocytic leukemia system. Fractionation, accompanied by monitoring for biological activity, afforded a novel phytoquinoid derivative jacaranone, which exhibited both in vivo antitumor and in vitro cytotoxic activity. beta-Sitosterol, betulinic acid, ursolic acid, 2alpha-hydroxyursolic acid, 2alpha,3alpha-dihydroxyurs-12-en-28-oic acid and a new triterpene acid, jacarandic acid, were also isolated. The structure elucidation of jacarandic acid is described. PMID:875643

  3. Pollination Biology of Jacaranda oxyphylla with an Emphasis on Staminode Function

    PubMed Central

    Guimarães, Elza; di Stasi, Luiz Claudio; Maimoni-Rodella, Rita de Cassia Sindrônia

    2008-01-01

    Background and Aims Bignoniaceae is a Neotropical family with >100 genera, only two of which, Jacaranda and Digomphia, have a developed staminode. Jacaranda oxyphylla, whose flowers possess a conspicuous glandular staminode, is a zoophilous cerrado species. Here, the composition of the secretion of the glandular trichome and the influence of the staminode on the pollination biology and reproductive success of J. oxyphylla were studied. Methods The floral morphology, pollen viability, stigma receptivity, nectar volume and nectar concentration were studied. Compatibility system experiments were performed and floral visitors were observed and identified. Experiments comparing the effect of staminode presence and absence on pollen removal and pollen deposition efficiency were conducted in open-pollinated flowers. Histochemistry, thin-layer chromatography (TLC) and gas chromatography coupled to flame ionization detection (GC–FID) analyses were performed to determine the main chemical components of the staminode's glandular trichome secretion. Key Results Flower anthesis lasted 2 d and, despite the low frequency of flower visitation, pollination seemed to be effected mainly by medium-sized Eulaema nigrita and Bombus morio bees, by the small bee Exomalopsis fulvofasciata and occasionally by hummingbirds. Small bees belonging to the genera Ceratina, Augochlora and Trigona were frequent visitors, collecting pollen. Jacaranda oxyphylla is predominantly allogamous. Staminode removal resulted in fewer pollen grains deposited on stigmas but did not affect total pollen removal. The secretion of capitate glandular trichome occurs continually; the main chemical compounds detected histochemically were phenolic and terpenoid (essential oils and resins). Monoterpene cineole, pentacyclic triterpenes and steroids were identified by TLC and GC–FID. Conclusions The staminode of J. oxyphyllla is multifunctional and its importance for female reproductive success was attributed mainly to the secretion produced by capitate glandular trichomes. This secretion is involved in complex chemical interactions with pollinating bees, including the solitary bees Euglossini. These bees are common pollinators of various species of Jacaranda. PMID:18765441

  4. Anti-tumor potential and acute toxicity of Jacaranda puberula Cham. (Bignoniacea).

    PubMed

    de-Almeida, Michelle Rodrigues-Ayres; Ramos-Leal, Ivana Correa; Ruela, Halliny Siqueira; Justo-Araujo, Maria da-Graça; Martins, Thiago Martino; Pinto-Coelho, Marsen Garcia; Kuster, Ricardo Machado; Carvalho-Sabino, Kátia Costa

    2013-09-01

    Cancer chemotherapy is an important strategy to treat this leading cause of death worldwide and plants may constitute a source of new antineoplastic agents. This work fractionated the ethanolic extract of Jacaranda puberula leaves and studied the in vitro antitumoral action and some toxicological effects of the most bioactive fraction. Cell lines related to worldwide cancers were used. The Dichloromethane (DCM) and PP fractions were the most bioactive ones. The anti-tumoral action of the DCM fraction was higher than that of the crude EtOH extract while that of PP fraction was higher than the original one (DCM) for both breast (MCF-7), prostate (PC3) and lung (A549) tumor cells, chronic leukemia cells. The K562 cells were the most sensitive cell line. The PP fraction (20 ?g/mL) cytotoxicity for these cells was similar to that of the ursolic acid triterpene or the antineoplastic ethoposide. The PP fraction inhibited K562 cell proliferation without cell cycle arrest in a specific phase or apoptosis. PP increased the mitochondrial reduction activity of lymphocytes. After a single dose by oral route, PP fraction did not induce intrinsic acute toxicity or animal death. This work demonstrated that the J. puberula fraction (PP) present high in vitro anti-tumoral effect with no cytotoxicity for immune system cells or oral acute toxicity, improving the Jacaranda puberula ethnopharmacology and reporting new biological effects for the genus Jacaranda. PMID:24035942

  5. Induction of apoptotic cell death in HL-60 cells by jacaranda seed oil derived fatty acids.

    PubMed

    Yamasaki, Masao; Motonaga, Chihiro; Yokoyama, Marino; Ikezaki, Aya; Kakihara, Tomoka; Hayasegawa, Rintaro; Yamasaki, Kaede; Sakono, Masanobu; Sakakibara, Yoichi; Suiko, Masahito; Nishiyama, Kazuo

    2013-01-01

    Various fatty acids are attracting considerable interest for their anticancer effects. Among them, fatty acids containing conjugated double bonds show one of the most potent cytotoxic effects on cancer cells. Here, we focused on the cancer cell killing activity of jacaranda seed oil. The seed oil of jacaranda harvested from Miyazaki in Japan contained 30.9% cis-8, trans-10, cis-12 octadecatrienoic acid, called jacaric acid (JA). Fatty acid prepared from this oil (JFA) and JA strongly induced cell death in human leukemia HL-60 cells. On the other hand, linoleic acid and trans-10, cis-12 conjugated linoleic acid (<10 ?M) did not affect cell proliferation and viability. An increase in the sub-G? population and internucleosomal fragmentation of DNA was observed in JA- and JFA-treated cells, indicating induction of apoptotic cell death. Finally, the cytotoxic effects of JA and JFA were completely abolished by ?-tocopherol. Taken together, these data suggest that jacaranda seed oil has potent apoptotic activity in HL-60 cells through induction of oxidative stress. PMID:24200941

  6. REMARKABLE TREES ON NII CAMPUS 1. The lilac-blue wonder

    E-print Network

    Bhalla, Upinder S.

    to 16 20-22 pairs of pinnae along the rachis. Each pinna has 13-20 pairs of leaflets. The lavender blue of the word 'jacaranda' refers to this feature. The tree erupts in a blaze of brilliant lavender or purple

  7. Phenolic compounds from Jacaranda caroba (Vell.) A. DC.: approaches to neurodegenerative disorders.

    PubMed

    Ferreres, Federico; Grosso, Clara; Gil-Izquierdo, Angel; Valentão, Patrícia; Andrade, Paula B

    2013-07-01

    Diseases affecting the central nervous system are spread throughout the world. As so, more efficient and safe neuroprotective drugs are required. The present study describes, for the first time, the phenolic composition and bioactivity of Jacaranda caroba (Vell.) A. DC, a species whose infusion is consumed as traditional medicine. The HPLC-DAD-ESI/MS(n) analysis revealed the presence of four dicaffeoyl acid derivatives and nine flavonoids, comprising quercetin, kaempferol and isorhamnetin derivatives. Twelve compounds are described for the first time in Jacaranda genus. Although isorhamnetin-3-O-rhmanoside-7,4'-di-O-glucoside and quercetin-3-O-(2-pentosyl)hexoside are the main metabolites in both aqueous and hydromethanolic extracts, qualitative and quantitative differences were found between them. Aqueous extract is richer in dicaffeoyl acid derivatives. Both extracts proved to be strong radicals' scavengers and effective monoamine-oxidase A inhibitors, but showed weak protection against cholinesterases' activity. The results highlight the value of J. caroba as a source of health-promoting antioxidants and antidepressant compounds. PMID:23524314

  8. Trees

    NSDL National Science Digital Library

    This tutorial covers various aspects of trees. It explains which chemicals cause leaves to change colors, how the process of photosynthesis works, the functions of bark, roots, pollen and leaves, and the effect of trees on nearby temperature.

  9. Trees, Trees, Trees!

    NSDL National Science Digital Library

    1998-01-01

    In these activities, students increase their awareness and knowledge of trees through research, literature and hands-on contact. The students will adopt and identify a tree of their choice, make a rubbing of the bark, draw a picture, and research about their tree. They will also write an original piece about their tree, document how it changes throughout the year, and learn the difference between deciduous and coniferous trees.

  10. Pioneer and late stage tropical rainforest tree species (French Guiana) growing under common conditions differ in leaf gas exchange regulation, carbon isotope discrimination and leaf water potential

    Microsoft Academic Search

    R. Huc; A. Ferhi; J. M. Guehl

    1994-01-01

    Leaf gas exchange rates, predawn ?wp and daily minimum ?wm leaf water potentials were measured during a wet-to-dry season transition in pioneer (Jacaranda copaia, Goupia glabra andCarapa guianensis) and late stage rainforest tree species (Dicorynia guianensis andEperua falcata) growing in common conditions in artificial stands in French Guiana. Carbon isotope discrimination (?) was assessed by measuring the stable carbon isotope

  11. Subacute and Reproductive Oral Toxicity Assessment of the Hydroethanolic Extract of Jacaranda decurrens Roots in Adult Male Rats

    PubMed Central

    Santos, Joyce Alencar; Arruda, Aline; Cardoso, Claudia Andrea Lima; Vieira, Maria do Carmo; Piccinelli, Ana Cláudia; Figueiredo de Santana Aquino, Diana; Kassuya, Cândida Aparecida Leite; Arena, Arielle Cristina

    2013-01-01

    Jacaranda decurrens subsp. symmetrifoliolata Farias & Proença (Bignoniaceae) is a species traditionally used for the treatment of inflammatory and infectious diseases. Previous findings from our group reported scientifically that J. decurrens has anti-inflammatory efficacy. However, more toxicological studies are needed to support and ensure its safe use. The present study was carried out to evaluate the toxic effects of a prolonged treatment with hydroethanolic root extract of J. decurrens (EJD) on hematological, biochemical, and reproductive parameters in adult male rats. The animals received by oral gavage 0; 250; 500; or 1000?mg/kg body weight of EJD for 28 days. After the treatment, biochemical, hematological, histopathological, and reproductive parameters were analyzed. The EJD treatment did not cause adverse effects on body weight gain, feed and water consumption, hematological and biochemical profiles, or histopathological analysis of liver and kidney. Similarly, there were no statistically significant differences in reproductive parameters, such as sperm production, number of sperm in the epididymis, and sperm morphology. These results demonstrate the absence of subacute toxicity as a result of the oral treatment with EJD for 28 days in adult male rats. However, other studies should be performed to evaluate the total safety of this plant. PMID:24348699

  12. Screening for antimicrobial activity of ten medicinal plants used in Colombian folkloric medicine: A possible alternative in the treatment of non-nosocomial infections

    Microsoft Academic Search

    Jhon J Rojas; Veronica J Ochoa; Saul A Ocampo; John F Muñoz

    2006-01-01

    BACKGROUND: The antimicrobial activity and Minimal Inhibitory Concentration (MIC) of the extracts of Bidens pilosa L., Bixa orellana L., Cecropia peltata L., Cinchona officinalis L., Gliricidia sepium H.B. & K, Jacaranda mimosifolia D.Don, Justicia secunda Vahl., Piper pulchrum C.DC, P. paniculata L. and Spilanthes americana Hieron were evaluated against five bacteria (Staphylococcus aureus, Streptococcus ? hemolític, Bacillus cereus, Pseudomonas aeruginosa,

  13. Toward a predictive model for water and carbon fluxes of non-native trees in urban habitats

    NASA Astrophysics Data System (ADS)

    McCarthy, H. R.; Jenerette, G. D.; Pataki, D. E.

    2008-12-01

    There is considerable interest in estimating uptake of water and carbon by urban trees, in order to assess some of the major costs and benefits associated with maintaining or expanding urban tree cover. However, making large-scale estimates of water and carbon fluxes is challenging in urban ecosystems, where community composition and environmental conditions are highly altered and experimental data is sparse. This is particularly true in regions such as southern California, where few trees are native, yet many species can flourish given supplemental irrigation. In such scenarios one practical way to scale water and carbon fluxes may be to identify reliable traits which can be used to predict gas exchange when trees are transplanted to a new environment. To test this approach, leaf level gas exchange measurements were conducted on eight common urban tree species within the Los Angeles basin. The objective was to determine how well gas exchange parameters, including maximum photosynthesis and stomatal conductance, sensitivity of stomatal conductance to vapor pressure deficit (VPD), and water use efficiency (WUE), can be predicted based on the native habitat and climate (temperature and precipitation) of each study species. All of the species studied naturally occur in humid tropical or subtropical climate zones where precipitation varies widely from ~400 - 3000 mm per year. We found Jacaranda (Jacaranda chelonia) and honey locust (Gleditsia triacanthos) to have the highest photosynthesis and reference (at VPD=1 kPa) conductance, and to be most sensitive to VPD. WUE was found to be greatest in Indian laurel fig (Ficus microcarpa), rose gum (Eucalyptus grandis) and Queensland lacebark (Brachychiton discolor). The relative ordering of maximum photosynthesis and conductance across species was not entirely predictable based on our current knowledge of the native habitats of each species: several other species had similar native climates to Jacaranda and honey locust, yet had lower photosynthesis and conductance. However, WUE generally followed the expected trends, with species predicted to have low conductance showing higher WUE. This implies that WUE is strongly genetically controlled and may be predictable with knowledge of imported species' native habitat. Other traits, such as leaf nitrogen and isotopes, are also being investigated as proxies for detailed gas exchange measurements in this ecosystem. Further refinement of predictive factors will facilitate conceptual and quantitative models that can be used for robust scaling of water and carbon fluxes from trees to urban regions.

  14. Flower Face Face Face Face Flower Tree Tree Tree Tree

    E-print Network

    Chen, Tsuhan

    Flower Flower Flower Flower Flower Face Face Face Face Flower Flower Tree Tree Tree Tree Flower Sign Face Face Face Face Sign Sign Building Sign Water Sky Tree Building Building Building Sign Book Building Building Building Sign Bird Bird Road Tree Grass Road Road Bird Sky #12;Bird Bird Water Bird Grass

  15. What is a Tree? Tree terminology

    E-print Network

    Razak, Saquib

    1 Trees · What is a Tree? · Tree terminology · Why trees? · What is a general tree? · Implementing trees · Binary trees · Binary tree implementation · Application of Binary trees #12;2 What is a Tree? · A tree, is a finite set of nodes together with a finite set of directed edges that define parent

  16. Decision Trees Unpredictability Bias Improvements Decision Trees

    E-print Network

    Kjellström, Hedvig

    Decision Trees Unpredictability Bias Improvements Decision Trees #12;Decision Trees Unpredictability Bias Improvements 1 Decision Trees Using Trees Learning 2 Unpredictability Entropy Entropy for datasets Information Gain 3 Bias Bias Occam's principle Overfitting 4 Improvements #12;Decision Trees

  17. Maple tree

    NSDL National Science Digital Library

    Derek Ramsey (None; )

    2006-09-23

    Trees give animals shade and a place to live and hide. Trees give many animals food. They also take in carbon dioxide, which animals breathe out, and replace it with oxygen, which is what animals need to breathe.

  18. INCREASING TREE FAMILIES Michael Drmota

    E-print Network

    Drmota, Michael

    INCREASING TREE FAMILIES Michael Drmota Inst. of Discrete Mathematics and Geometry Vienna · Recursive Trees · Plane Oriented Trees · General Increasing Trees · Degree Distribution · Conclusion #12;Recursive Trees #12;Recursive Trees #12;Recursive Trees #12;Recursive Trees #12;Recursive Trees #12

  19. Tree Amigos.

    ERIC Educational Resources Information Center

    Center for Environmental Study, Grand Rapids, MI.

    Tree Amigos is a special cross-cultural program that uses trees as a common bond to bring the people of the Americas together in unique partnerships to preserve and protect the shared global environment. It is a tangible program that embodies the philosophy that individuals, acting together, can make a difference. This resource book contains…

  20. Talking Trees

    ERIC Educational Resources Information Center

    Tolman, Marvin

    2005-01-01

    Students love outdoor activities and will love them even more when they build confidence in their tree identification and measurement skills. Through these activities, students will learn to identify the major characteristics of trees and discover how the pace--a nonstandard measuring unit--can be used to estimate not only distances but also the…

  1. Factor Trees

    NSDL National Science Digital Library

    Math Playground

    2009-07-29

    This virtual manipulative allows students to find the prime factorization of numbers by completing factor trees. Then they may use a venn diagram to sort the prime factors to find the greatest common factor and the least common multiple.

  2. Factor Trees

    NSDL National Science Digital Library

    2010-01-01

    In this online activity, the learner finds the prime factorization of composite numbers by building factor trees. A second level includes finding the greatest common factor and the least common multiple by sorting factors using a Venn Diagram.

  3. Assessing the extent of "conflict of use" in multipurpose tropical forest trees: a regional view.

    PubMed

    Herrero-Jáuregui, Cristina; Guariguata, Manuel R; Cárdenas, Dairon; Vilanova, Emilio; Robles, Marco; Licona, Juan Carlos; Nalvarte, Walter

    2013-11-30

    In the context of multiple forest management, multipurpose tree species which provide both timber and non-timber forest products (NTFP), present particular challenges as the potential of conflicting use for either product may be high. One key aspect is that the magnitude of conflict of use can be location specific, thus adding complexity to policy development. This paper focuses on the extent to which the potential for conflict of use in multipurpose tree species varies across the Amazonian lowland forests shared by Peru, Bolivia, Colombia, Ecuador and Venezuela, emphasizing the economic dimension of conflict. Based on a review of the current normative and regulatory aspects of timber and NTFP extraction in the five countries, the paper also briefly discusses the opportunities and constraints for harmonization of timber and NTFP management of multipurpose species across the region. It was found that about half of the 336 timber species reviewed across the five countries also have non-timber uses. Eleven timber species are multipurpose in all five countries: Calophyllum brasiliense, Cedrela odorata, Ceiba pentandra, Clarisia racemosa, Ficus insipida, Jacaranda copaia, Schefflera morototoni, Simarouba amara and Terminalia amazonia. Seven other multipurpose species occurred only in either Venezuela (Tabebuia impetiginosa, Spondias mombin, Pentaclethra macroloba, Copaifera officinalis, Chlorophora tinctoria, Carapa guianensis) or Ecuador (Tabebuia chrysantha). Four multipurpose tree species presented the highest potential of conflict of use across the region: Dipteryx odorata, Tabebuia serratifolia, Hymenaea courbaril and Myroxylon balsamum yet these were not evenly distributed across all five countries. None of the five studied countries have specific legislation to promote sustainable use of any of the multipurpose species reported here and thus mitigate potential conflict of use; nor documented management options for integration or else segregation of both their timber and NTFP values. PMID:24061084

  4. Community Trees Community Tree Steward Program

    E-print Network

    Koford, Rolf R.

    1 Community Trees Community Tree Steward Program ...and justice for all The U.S. Department, Iowa February, 2001 Jeff Iles Department of Horticulture Iowa State University Most tree managers realize dead trees should be removed as soon as they are detected. But living trees also can be a threat

  5. Community Trees Power Lines and Trees

    E-print Network

    Koford, Rolf R.

    Community Trees Power Lines and Trees Introduction Trees serve many purposes in urban and rural trees near power lines. Most high voltage lines are not insulated, and contact will result in electric areas. To assure safe and reliable electric service, trimming or removal of trees is sometimes necessary

  6. Minimizing Tree Automata for Unranked Trees

    E-print Network

    Martens, Wim

    Minimizing Tree Automata for Unranked Trees Wim Martens Joachim Niehren Minimizing Tree Automata for Unranked Trees ­ p.1/20 #12;What and Why? To study the minimization problem for deterministic automata over unranked trees. Bottom-up deterministic: theoretical interest. E.g. do results from deterministic automata

  7. Article original Croissance et assimilation nette foliaire de jeunes

    E-print Network

    Boyer, Edmond

    of tropical rainforest trees (Bocoa prouacensis, Carapa guianensis, Carapa procera, Jacaranda copaia, Platonia; Inra/Elsevier, Paris.) tropical rainforest / net assimilation rate / growth rate / stem volume index

  8. Shrinking Trees

    Microsoft Academic Search

    Trevor Hastie; Daryl Pregibon

    Tree-based models provide an alternative to linear models for classification and regres- sion data. They are used primarily for exploratory analysis of complex data or as a diagnostic tool following a linear model analysis. They are also used as the end prod- uct in certain applications, such as speech recognition, medical diagnoses, and other instances where repeated fast classifications are

  9. Shade trees

    Microsoft Academic Search

    Robert L. Cook

    1984-01-01

    Shading is an important part of computer imagery, but shaders have been based on fixed models to which all surfaces must conform. As computer imagery becomes more sophisticated, surfaces have more complex shading characteristics and thus require a less rigid shading model. This paper presents a flexible tree-structured shading model that can represent a wide range of shading characteristics. The

  10. Tree Decline Shade trees often gradually lose

    E-print Network

    Tree Decline Shade trees often gradually lose vigor and may show off-color, small leaves, poor several years and is often re- ferred to as "tree decline," because it is a gradual loss of growth observed in the aboveground parts of the plant usually begin in the root system. Stress Factors Trees

  11. Tree Torture

    NSDL National Science Digital Library

    Science Update

    2002-06-10

    The San Pedro River is one of the only free-flowing waterways in Arizona. Though it's more of a small stream than a river, it nourishes a vibrant ecosystem known as a riparian area. Full of tall trees, it serves as a major flyway for migrating birds and provides a ribbon of green in an otherwise barren landscape. In this Science Update, you'll hear about the research being done to keep the San Pedro flowing.

  12. Tree Troubles

    NSDL National Science Digital Library

    This Topic in Depth explores some of the diseases and other threats that certain trees must contend with to remain healthy and vital. The first website (1), from the USDA Forest Service-St. Paul Field Office, contains a collection of archived publications designed to help people diagnose, control, and identify various threats to different types of trees. Examples of these publications include: How to Control Sapstreak Disease of Sugar Maple; How to Differentiate Dutch Elm Disease From Elm Phloem Necrosis; How to Identify and Manage Needlecast Diseases on Balsam Fir; and How to Manage Eastern White Pine to Minimize Damage from Blister Rust and White Pine Weevil, to name few. The second (2) site, Forest & Shade Tree Pathology, is an online textbook that was developed by Dr. James J. Worrall, a plant pathologist for the USDA Forest Service, and former professor at the College of Environmental Science and Forestry, State University of New York. Dr. Worrall's site contains information about rusts, foliage and root diseases, parasitic plants, cankers, abiotic diseases, and wilts as well as disease profiles for Swiss Needle Cast; Oak Wilt, Chestnut Blight, Armillaria Root Disease, and more. The third (3) site, Oak Wilt: A Threat to Red Oaks & White Oaks Species, was created by Dr. David L. Roberts at Michigan State University Extension. Dr. Robert's concise site contains brief sections addressing oak wilt distribution, field diagnosis, management, disease cycle, and more. The fourth (4) site, from the California Oak Mortality Task Force, contains images, publications, maps, and information about Sudden Oak Death-related research, management recommendations, nursery issues, and regulations. The final three websites come from the USDA Forest Service and contain information about different insect threats. The fifth (5) site offers information about the emerald ash borer. The sixth (6) site provides information about the gypsy moth, and the final (7) site contains information about the Asian longhorned beetle.

  13. Extrapolating Tree Transformations

    Microsoft Academic Search

    Ahmed Bouajjani; Tayssir Touili

    2002-01-01

    We consider the framework of regular tree model checking where sets of configurations of a system are represented by regular tree languages and its dynamics is modeled by a term rewriting system (or a regular tree transducer). We focus on the computation of the reachability set R?(L) where R is a regular tree transducer and L is a regular tree

  14. On generalized fat trees

    Microsoft Academic Search

    Sabine R. Öhring; Maximilian Ibel; Sajal K. Das; Mohan J. Kumar

    1995-01-01

    We introduce and analyze a new family of multiprocesser interconnection networks, called generalized fat trees, which include as special cases the fat trees used for the connection machine architecture CM-5, pruned butterflies, and various other fat trees proposed in the literature. The generalized fat trees provide a formal unifying concept to design and analyse a fat tree based architecture. The

  15. American Chestnut Tree

    NSDL National Science Digital Library

    KET

    2008-09-02

    This annotated slideshow adapted from KET's Electronic Field Trip to the Forest illustrates how blight decimated the American chestnut tree and the methods scientists use to identify and pollinate the remaining trees to create blight-resistant trees.

  16. Trees and Air Quality

    NSDL National Science Digital Library

    In this activity, students describe the positive effects that trees have on air quality and determine how to landscape a home with trees to decrease energy use. Students will draw a map of their yard or school site showing the location of trees and check a leaf of each tree for particulates. They will then make observations on several different days to determine which trees save energy and draw on their map where more trees should be planted to save energy.

  17. Protected trees A guide to tree preservation procedures

    E-print Network

    Protected trees A guide to tree preservation procedures #12;Protected trees A guide to tree trees: A guide to tree preservation procedures Introduction This leaflet is written for tree owners, their neighbours and local community groups, and answers some of the most common questions about tree preservation

  18. Essential Kurepa Trees Versus Essential Jech Kunen Trees1

    E-print Network

    Jin, Renling

    Essential Kurepa Trees Versus Essential Jech Kunen Trees1 Renling Jin2 & Saharon Shelah3 Abstract By an !1 tree we mean a tree of cardinality !1 and height !1. An !1 tree is called a Kurepa tree if all its levels are countable and it has more than !1 branches. An !1 tree is called a Jech Kunen tree if it has

  19. Tree Comparison Contest: TreeJuxtaposer

    E-print Network

    Munzner, Tamara

    Tree Comparison Contest: TreeJuxtaposer James Slack, Tamara Munzner (UBC) François Guimbretière Tasiran, Li Zhang, Yunhong Zhou, SIGGRAPH 2003 · Entry: http://www.cs.ubc.ca/~tmm/papers/contest03 · Visit our interactive poster for demonstration #12;

  20. A tree-to-tree model for statistical machine translation

    E-print Network

    Cowan, Brooke A. (Brooke Alissa), 1972-

    2008-01-01

    In this thesis, we take a statistical tree-to-tree approach to solving the problem of machine translation (MT). In a statistical tree-to-tree approach, first the source-language input is parsed into a syntactic tree ...

  1. 13 C nuclear magnetic resonance spectroscopic analysis of seed oils containing conjugated unsaturated acids

    Microsoft Academic Search

    A. P. Tulloch

    1982-01-01

    13C Nuclear magnetic resonance spectroscopy has been used in a nondestructive investigation of conjugated unsaturated acids\\u000a in seed oil triacylglycerols. Spectra of seven seed oils, fromPunica granatum, Cucurbita palmata, Jacaranda mimosifolia, Centranthus ruber, Catalpa bignonioides, Chilopsis linearis andCalendula officinalis, containing among them six isomeric trienoic acids,cis,trans,cis- andtrans,trans,cis-8,10,12-,cis,trans,cis-, cis,trans,trans-, trans,trans,cis- andtrans,trans,trans-9,11,13-octadecatrienoic acids, and of the oil ofImpatiens balsamina containingcis,trans,trans,cis-9,11,13,15-octadecatetraenoic acid, have

  2. Limit Laws for Functions of Fringe trees for Binary Search Trees and Recursive Trees

    E-print Network

    Janson, Svante

    Limit Laws for Functions of Fringe trees for Binary Search Trees and Recursive Trees Cecilia of binary search trees and random recursive trees. In particular, we give simple new proofs of the fact that the number of fringe trees of size k = kn in the binary search tree and the random recursive tree (of total

  3. A dynamic fault tree

    Microsoft Academic Search

    Marko ?epin; Borut Mavko

    2002-01-01

    The fault tree analysis is a widely used method for evaluation of systems reliability and nuclear power plants safety. This paper presents a new method, which represents extension of the classic fault tree with the time requirements. The dynamic fault tree offers a range of risk informed applications. The results show that application of dynamic fault tree may reduce the

  4. Tree Lines: Discussion

    Microsoft Academic Search

    P. G. Jarvis; J. Grace; N. Hutchings; J. L. Monteith; W. J. Shuttleworth; D. Fowler; J. Corlett; J. Thomas

    1989-01-01

    Trees do not generally grow in places where the mean temperature of the warmest month is less than about 10 ^circ C. At their limit, trees are often short and crooked, the condition known as krummholz; and the transition from tall forest to dwarf shrubby vegetation is often abrupt, forming a distinct tree line. Tree lines fluctuate with climatic change.

  5. Random Trees and Applications

    E-print Network

    Durrett, Richard

    Random Trees and Applications Jean-Fran¸cois Le Gall1 Notes prepared for the Cornell Summer School;2 #12;Chapter 1 From Discrete to Continuous Trees In this chapter, we first explain how discrete random trees can be coded by discrete paths called the height function and the contour function of the tree. We

  6. Tree Rings as Environmental

    E-print Network

    Grissino-Mayer, Henri D.

    359 Tree Rings as Environmental Indicators year to year throughout the life of a tree. This pattern, recog- nized that trees form new rings of growth each year, but the modern development. Because he knew that plant growth was affected by changes in cli- mate, he thought that the size of a tree

  7. Categorizing Ideas about Trees: A Tree of Trees

    PubMed Central

    Fisler, Marie; Lecointre, Guillaume

    2013-01-01

    The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize conceptual parts of ideas, writings and drawings about trees contained in 41 main writings; we detect shared parts among authors and code them into a 91-characters matrix and use a tree representation to show who shares what with whom. In other words, we propose a hierarchical representation of the shared ideas about trees among authors: this produces a “tree of trees.” Then, we categorize schools of tree-representations. Classical schools like “cladists” and “pheneticists” are recovered but others are not: “gradists” are separated into two blocks, one of them being called here “grade theoreticians.” We propose new interesting categories like the “buffonian school,” the “metaphoricians,” and those using “strictly genealogical classifications.” We consider that networks are not useful to represent shared ideas at the present step of the study. A cladogram is made for showing who is sharing what with whom, but also heterobathmy and homoplasy of characters. The present cladogram is not modelling processes of transmission of ideas about trees, and here it is mostly used to test for proximity of ideas of the same age and for categorization. PMID:23950877

  8. Tree Tectonics

    NASA Astrophysics Data System (ADS)

    Vogt, Peter R.

    2004-09-01

    Nature often replicates her processes at different scales of space and time in differing media. Here a tree-trunk cross section I am preparing for a dendrochronological display at the Battle Creek Cypress Swamp Nature Sanctuary (Calvert County, Maryland) dried and cracked in a way that replicates practically all the planform features found along the Mid-Oceanic Ridge (see Figure 1). The left-lateral offset of saw marks, contrasting with the right-lateral ``rift'' offset, even illustrates the distinction between transcurrent (strike-slip) and transform faults, the latter only recognized as a geologic feature, by J. Tuzo Wilson, in 1965. However, wood cracking is but one of many examples of natural processes that replicate one or several elements of lithospheric plate tectonics. Many of these examples occur in everyday venues and thus make great teaching aids, ``teachable'' from primary school to university levels. Plate tectonics, the dominant process of Earth geology, also occurs in miniature on the surface of some lava lakes, and as ``ice plate tectonics'' on our frozen seas and lakes. Ice tectonics also happens at larger spatial and temporal scales on the Jovian moons Europa and perhaps Ganymede. Tabletop plate tectonics, in which a molten-paraffin ``asthenosphere'' is surfaced by a skin of congealing wax ``plates,'' first replicated Mid-Oceanic Ridge type seafloor spreading more than three decades ago. A seismologist (J. Brune, personal communication, 2004) discovered wax plate tectonics by casually and serendipitously pulling a stick across a container of molten wax his wife and daughters had used in making candles. Brune and his student D. Oldenburg followed up and mirabile dictu published the results in Science (178, 301-304).

  9. COMPONENT User's Guide Random trees

    E-print Network

    Page, Roderic

    COMPONENT User's Guide Chapter 6 Random trees COMPONENT can generate a variety of trees at "random," and for small numbers of leaves it can generate all possible trees. These trees have several uses: n as user trees for phylogeny programs that lack the facility to examine all trees or sets of random trees (e

  10. From Gene Trees to Species Trees II: Species Tree Inference by Minimizing Deep

    E-print Network

    Zhang, Louxin

    From Gene Trees to Species Trees II: Species Tree Inference by Minimizing Deep Coalescence Events Louxin Zhang Abstract--When gene copies are sampled from various species, the resulting gene tree might disagree with the containing species tree. The primary causes of gene tree and species tree discord include

  11. Become "Tree Detectives": Identifying Broadleaf Trees...

    E-print Network

    Koford, Rolf R.

    Forest and ShadeTrees of Iowa. Peter J. van der Linden & Donald R. Farrar, Iowa State University Press for loan, ISU Forestry Extension at 515-294-6739 or Trees Forever at 1-800-369-1269. needles seed cone Pine species have needles in a bundle. Fir species have flat shaped needles and cones that sit upright

  12. Tea Tree Oil

    MedlinePLUS

    From the National Institutes of Health ... main content U.S. Department of Health & Human Services National Institutes of Health Search NIH…Turning Discovery Into Health Follow ... Tea Tree Oil Common Names: Australian tea tree oil, tea ...

  13. Pine tree forest

    NSDL National Science Digital Library

    Katie Hale (California State University, Fullerton; Student, Biological Sciences)

    2007-01-13

    The pine tree demonstrates the differences among gymnosperms and bryophytes and seedless vascular plants. Pine trees have separate cones with pollen and ovulates. Wind blows the pollen onto the ovulate cone and seeds are produced.

  14. Tree Classification Software

    NASA Technical Reports Server (NTRS)

    Buntine, Wray

    1993-01-01

    This paper introduces the IND Tree Package to prospective users. IND does supervised learning using classification trees. This learning task is a basic tool used in the development of diagnosis, monitoring and expert systems. The IND Tree Package was developed as part of a NASA project to semi-automate the development of data analysis and modelling algorithms using artificial intelligence techniques. The IND Tree Package integrates features from CART and C4 with newer Bayesian and minimum encoding methods for growing classification trees and graphs. The IND Tree Package also provides an experimental control suite on top. The newer features give improved probability estimates often required in diagnostic and screening tasks. The package comes with a manual, Unix 'man' entries, and a guide to tree methods and research. The IND Tree Package is implemented in C under Unix and was beta-tested at university and commercial research laboratories in the United States.

  15. Minimal locked trees

    E-print Network

    Ballinger, Brad

    Locked tree linkages have been known to exist in the plane since 1998, but it is still open whether they have a polynomial-time characterization. This paper examines the properties needed for planar trees to lock, with a ...

  16. Graph homomorphisms between trees

    E-print Network

    Csikvari, Peter

    In this paper we study several problems concerning the number of homomorphisms of trees. We begin with an algorithm for the number of homomorphisms from a tree to any graph. By using this algorithm and some transformations ...

  17. RECURSIVE TREES Michael Drmota

    E-print Network

    Drmota, Michael

    copies of ancient texts · convex hull algorithms · ... #12;Enumeration of Recursive Trees All recursive Combinatorial Description · labelled rooted tree · labels are strictly increasing · no left-to-right order (non-planar

  18. Binary Search Trees Page 1 Binary Search Trees

    E-print Network

    Allan, Vicki H.

    Binary Search Trees Page 1 Chapter 4 Trees Binary Search Trees · Definition o All keys are distinct subtree is greater than the root. o Left and right subtrees are binary search trees. · Figure 1 is an example: Figure 1 Binary Search Tree · Where would you add X, B, and E? · At seats, build tree from

  19. Tree SelectionTree Selection Why is selection important?

    E-print Network

    Tree SelectionTree Selection #12; Why is selection important? What happens when we think it's not important? Not all trees grow alike Incompatible situation Average life span of city tree is 7-13 years end up with a tree in the wrong location. #12;Tree Selection Style I Let's Try Another Selection

  20. 8-ary tree. Overview of B-Trees

    E-print Network

    Yorke, James

    Page Page Figure A.1 8-ary tree. APPENDIX A Overview of B-Trees Tree-based searching methods large, we find that often the tree is too large to fit in memory at once. Therefore, the tree is stored. In such an environment, the branches in the tree contain disk addresses, and it is not uncommon for a comparison

  1. Kids for Trees

    NSDL National Science Digital Library

    This website provides references for students about the importance of trees to people and the environment. It discusses the interactions between trees and other organisms, how trees provide for their food and water needs, and how people use and work with trees. A teacher's guide provides background information, project and activity ideas, evaluation questions, and extensions that correspond with each student reference page. Links to related resources are included.

  2. Minnesota's Forest Trees. Revised.

    ERIC Educational Resources Information Center

    Miles, William R.; Fuller, Bruce L.

    This bulletin describes 46 of the more common trees found in Minnesota's forests and windbreaks. The bulletin contains two tree keys, a summer key and a winter key, to help the reader identify these trees. Besides the two keys, the bulletin includes an introduction, instructions for key use, illustrations of leaf characteristics and twig…

  3. Pecan tree biomass estimates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Allometric equations were developed for orchard-grown pecan [Carya illinoinensis (Wangenh.) C. Koch] trees. Trees, ranging in size from 22 to 33 cm in trunk diameter 1.4 m above the ground, were destructively harvested from two sites. The entire above-ground portion of the trees was harvested and...

  4. Fault Tree Analysis

    Microsoft Academic Search

    Liudong Xing; Suprasad V. Amari

    In this chapter, a state-of-the-art review of fault tree analysis is presented. Different forms of fault trees, including\\u000a static, dynamic, and non-coherent fault trees, their applications and analyses will be discussed. Some advanced topics such\\u000a as importance analysis, dependent failures, disjoint events, and multistate systems will also be presented.

  5. RC trees revisited

    Microsoft Academic Search

    Mehinet A. Cirit

    1988-01-01

    RC tree approximation is a computationally simple method for calculating the signal delay of MOS circuits with several states of fanout. The author derives a formal solution of RC tree equations. Based on this solution, it is shown that even though waveforms found using RC tree approximation are inaccurate, delays are exact. The author derives the dependence of the delays

  6. Representing Trees with Constraints 

    E-print Network

    Curry, Benjamin; Wiggins, Geraint; Hayes, Gillian

    This paper presents a method for representing trees using constraint logic programming over finite domains. We describe a class of trees that is of particular interest to us and how we can represent the set of trees belonging to that class using...

  7. Boosting Decision Trees

    Microsoft Academic Search

    Harris Drucker; Corinna Cortes

    1995-01-01

    A new boosting algorithm of Freund and Schapire is used to improve the performance of decision trees which are constructed usin: the information ratio criterion of Quinlan's C4.5 algorithm. This boosting algorithm iteratively constructs a series of decision tress, each decision tree being trained and pruned on examples that have been filtered by previously trained trees. Examples that have been

  8. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Color-shifted complexes Weighted spanning tree enumerators of color-shifted complexes Ghodratollah Aalipour1,2 Art Duval1 1University Ghodratollah Aalipour, Art Duval Spanning tree enumerators of color-shifted complexes #12;Spanning trees

  9. From gene trees to species trees through a supertree approach

    E-print Network

    Paris-Sud XI, Université de

    From gene trees to species trees through a supertree approach Celine Scornavacca1,2, , Vincent Abstract. Gene trees are leaf-labeled trees inferred from molecular se- quences. Due to duplication events arising in genome evolution, gene trees usually have multiple copies of some labels, i.e. species

  10. Discordance of species trees with their most likely gene trees

    E-print Network

    Degnan, James

    Discordance of species trees with their most likely gene trees James H. Degnan & Noah A. Rosenberg sort during speciation, gene trees may differ in topology from each other and from species trees find that for any species tree topology with five or more species, there exist branch lengths for which

  11. From Gene Trees to Species Trees through a Supertree Approach

    E-print Network

    Paris-Sud XI, Université de

    From Gene Trees to Species Trees through a Supertree Approach Celine Scornavacca1,2, , Vincent Abstract. Gene trees are leaf-labeled trees inferred from molecular se- quences. Due to duplication events arising in genome evolution, gene trees usually have multiple copies of some labels, i.e. species

  12. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Complete colorful complexes Weighted spanning tree enumerators of complete colorful complexes Ghodratollah Aalipour1,2 Art Duval1 1 Aalipour, Art Duval Spanning tree enumerators of complete colorful complexes #12;Spanning trees of graphs

  13. The cut-tree of large recursive trees Jean Bertoin

    E-print Network

    Paris-Sud XI, Université de

    The cut-tree of large recursive trees Jean Bertoin Abstract Imagine a graph which is progressively destroyed by cutting its edges one after the other in a uniform random order. The so-called cut-tree records with a natural probability mass. In this work, we show that the cut-tree of a random recursive tree of size n

  14. Friends of Trees

    NSDL National Science Digital Library

    Based in Portland, Oregon, the Friends of Trees organization is dedicated to restoring urban forests around the country, with a particular emphasis on the Portland metropolitan area. As their Web site notes, "Trees are an essential part of the urban ecosystem. They help keep our water and air clean, prevent erosion, provide wildlife habitat, and make neighborhoods greener, more beautiful places to live." On the site, visitors can read about their ongoing planting activities and browse the newsletter they publish three times a year. For most visitors, the most helpful area of the site will be the Tree Resources section. Here, users can look through a fact sheet on the benefits of trees in urban environments, the care and maintenance of trees, and a large tree database.

  15. COMPONENT User's Guide Working with trees

    E-print Network

    Page, Roderic

    COMPONENT User's Guide Chapter 2 Working with trees This chapter gives you information on basic tree operations. The topics covered include: n reading and writing files of trees n editing trees n displaying and printing trees n selecting subsets of trees n pruning trees n rooting trees n computing tree

  16. Recursively Imputed Survival Trees

    PubMed Central

    Zhu, Ruoqing; Kosorok, Michael R.

    2011-01-01

    We propose recursively imputed survival tree (RIST) regression for right-censored data. This new nonparametric regression procedure uses a novel recursive imputation approach combined with extremely randomized trees that allows significantly better use of censored data than previous tree based methods, yielding improved model fit and reduced prediction error. The proposed method can also be viewed as a type of Monte Carlo EM algorithm which generates extra diversity in the tree-based fitting process. Simulation studies and data analyses demonstrate the superior performance of RIST compared to previous methods. PMID:23125470

  17. COMPONENT User's Guide Comparing trees

    E-print Network

    Page, Roderic

    COMPONENT User's Guide Chapter 5 Comparing trees This chapter describes the tree comparison measures available in COMPONENT, and the various ways you can compare trees using the program. Among the possible uses of tree comparison measures are: n comparing trees for the same taxa computed from different

  18. TREE RISK ASSESSMENT Importance of

    E-print Network

    TREE RISK ASSESSMENT #12;Importance of Assessing The Risk Trees provide significant benefits to our homes and cities, but when trees fall and injure people or damage property, they are liabilities. Taking care of tree hazards makes your property safer and prolongs the life of the tree. (ISA

  19. Rooting for Trees: Volunteers to Plant 20 Trees, Mark Tree Campus USA Honor

    E-print Network

    Hofmann, Hans A.

    Rooting for Trees: Volunteers to Plant 20 Trees, Mark Tree Campus USA Honor March 22, 2013 Event at The University of Texas at Austin will join the university urban forestry team in planting 20 large trees on the grounds of the Dell Pediatric Research Institute. Volunteers will also mulch more than 100 existing trees

  20. Tree height measurement protocol J Chave Page 1 Measuring tree height for tropical forest trees

    E-print Network

    Chave, Jérôme

    Tree height measurement protocol ­ J Chave Page 1 Measuring tree height for tropical forest trees Diversité Biologique Université Paul Sabatier 31000 Toulouse, France 1. Introduction Tree height is a fundamental geometrical variable for trees. Unfortunately, most measures are based on visual inspection

  1. Apple Tree, NH Big Tree for May By Anne Krantz, NH Big Tree Team,

    E-print Network

    New Hampshire, University of

    Apple Tree, NH Big Tree for May By Anne Krantz, NH Big Tree Team, UNH Cooperative Extension The explosion of apple blossoms in May transforms the most gnarled old tree into a delicate cloud of beauty (1817-1862) in his essay "The Wild Apple Tree," described the blossoms perfectly: `The flowers

  2. Biodiversity and Evolutionary Trees

    NSDL National Science Digital Library

    2013-09-14

    In this interactive activity, learners analyze seashells to explore phylogeny and evolution. Learners identify similar and dissimilar seashells to create a phylogenetic tree. The Teacher Guide includes pre-activity video clip suggestions and a pre-activity sorting exercise. The Teacher Guide also includes instructions on how learners can draw a phylogenetic tree instead of using the online interactive.

  3. Fault tree handbook

    Microsoft Academic Search

    D. F. Haasl; N. H. Roberts; W. E. Vesely; F. F. Goldberg

    1981-01-01

    This handbook describes a methodology for reliability analysis of complex systems such as those which comprise the engineered safety features of nuclear power generating stations. After an initial overview of the available system analysis approaches, the handbook focuses on a description of the deductive method known as fault tree analysis. The following aspects of fault tree analysis are covered: basic

  4. Total tree chips story

    Microsoft Academic Search

    1979-01-01

    A Minneapolis company, Total Tree Chips, Inc., originally formed to chip city trees killed by Dutch elm disease, has expanded to include operations such as clearing land for parks and shopping centers and selling some of the chipped material back to the owners for trails and landscaping. Excess chips are sold to civic and commercial developments for landscaping, to a

  5. Trees Are Terrific!

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1992-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. Contents are organized into the following sections: (1) "What Makes a Tree a Tree?," including information…

  6. Tree nut oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The major tree nuts include almonds, Brazil nuts, cashew nuts, hazelnuts, macadamia nuts, pecans, pine nuts, pistachio nuts, and walnuts. Tree nut oils are appreciated in food applications because of their flavors and are generally more expensive than other gourmet oils. Research during the last de...

  7. Survival of Trees

    NSDL National Science Digital Library

    National Science Foundation

    In this video a scientist explains how DNA extracted from ancient tree remains provides insights about how trees/plants have adapted, over time, to changes in CO2 in the atmosphere. Her lab research investigates changes in plant genotypes under experimental conditions that simulate potential changes in CO2 levels in the future.

  8. Tree ring analysis

    Microsoft Academic Search

    Hayet Laggoune; Sarifuddin; V. Guesdon

    2005-01-01

    Tree ring analysis provides useful data for dendrochnologists that can help them for better understanding of climatic and environmental changes. Yet detection and counting of rings in cross section of tree were realized manually which is time consuming and tedious work. Our research was motivated by the need of a fast and accurate method. This paper describes a semi automatic

  9. Shrinking Trees Trevor Hastie

    E-print Network

    Hastie, Trevor

    Shrinking Trees Trevor Hastie Daryl Pregibon AT&T Bell Laboratories 600 Mountain Avenue, Murray shrinking. The shrinking process is parameterized by a scalar which ranges from zero to one. A value of zero implies shrinking all fitted values to that of the root of the tree, whereas a value of one

  10. Trees From Helicopters, Continued

    NSDL National Science Digital Library

    Richard Konicek-Moran

    2009-04-01

    Maples are very interesting trees with lots of variation in form. They provide us with a view of diversity in plants as well as a chance to look at natural phenomena that is very common to anyone who has had a maple tree near them. The main purpose is to

  11. Extracting Species Trees From Complex Gene Trees: Reconciled Trees And Vertebrate Phylogeny

    E-print Network

    Page, Roderic

    Extracting Species Trees From Complex Gene Trees: Reconciled Trees And Vertebrate Phylogeny Roderic for nine vertebrate genes (aldolase, -feto- protein, lactate dehydrogenase, prolactin, rhodopsin with currently accepted vertebrate relationships. 2000 Academic Press INTRODUCTION ``Regarding the analysis

  12. binary-tree B-tree Hashing Space-Filling based location

    E-print Network

    Ooi, Beng Chin

    #12;#12;#12;binary-tree B-tree Hashing Space-Filling Quad-tree based location keys R -tree+ PLOP Hashing EXCELL R-tree Grid-files kd-tree kd-B-treeBD-tree 1984 1985 1986 1987 1988 1989 1990 1991 1992 LSD-tree GBD-tree skd-tree Packed R-tree multi-level GF Cell-tree hB-tree R-files GGF mkd-tree 4d-tree 4d-tree

  13. Ash Tree Identification Key Ash Tree Characteristics

    E-print Network

    Walter, M.Todd

    berries Walnut, Hickory, Mountain-Ash: alternate branching #12;Identifying Emerald Ash Borer what to do if you think you have the ash-killing Emerald Ash Borer (EAB) in your ash tree Verify the signs of EAB: 1 activity Educate Yourself: Emerald Ash Borer information and links can be found at http://nyis.info Report

  14. On reconfiguring tree linkages: Trees can lock

    Microsoft Academic Search

    Therese C. Biedl; Erik D. Demaine; Martin L. Demaine; Sylvain Lazard; Anna Lubiw; Joseph O'rourke; Steve Robbins; Ileana Streinu; Godfried T. Toussaint; Sue Whitesides

    1998-01-01

    It is an open problem to determine whether a polygonal chain can be "straightened" inthe plane if its links are not allowed to cross. This problem been raised independently byseveral researchers, including J. Mitchell, and W. Lenhart and S. Whitesides [LW95]. In thispaper we propose a related question: whether a tree linkage can always be "straightened" inthe plane, without allowing

  15. Phylogenetic trees in bioinformatics

    SciTech Connect

    Burr, Tom L [Los Alamos National Laboratory

    2008-01-01

    Genetic data is often used to infer evolutionary relationships among a collection of viruses, bacteria, animal or plant species, or other operational taxonomic units (OTU). A phylogenetic tree depicts such relationships and provides a visual representation of the estimated branching order of the OTUs. Tree estimation is unique for several reasons, including: the types of data used to represent each OTU; the use ofprobabilistic nucleotide substitution models; the inference goals involving both tree topology and branch length, and the huge number of possible trees for a given sample of a very modest number of OTUs, which implies that fmding the best tree(s) to describe the genetic data for each OTU is computationally demanding. Bioinformatics is too large a field to review here. We focus on that aspect of bioinformatics that includes study of similarities in genetic data from multiple OTUs. Although research questions are diverse, a common underlying challenge is to estimate the evolutionary history of the OTUs. Therefore, this paper reviews the role of phylogenetic tree estimation in bioinformatics, available methods and software, and identifies areas for additional research and development.

  16. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Color-shifted complexes Weighted spanning tree enumerators of color-shifted complexes Ghodratollah Aalipour1,2 Art Duval1 1University in St. Louis October 20, 2013 Ghodratollah Aalipour, Art Duval Spanning tree enumerators of color

  17. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Critical group of graphs Critical group of simplicial complexes Spanning trees and the critical group of simplicial complexes Art Duval1 Mathematics Colloquium New Mexico State University October 20, 2011 Duval, Klivans, Martin Spanning trees

  18. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Critical group of graphs Critical group of simplicial complexes Spanning trees and the critical group of simplicial complexes Art Duval1 of Kansas Discrete CATS seminar University of Kentucky March 30, 2011 Duval, Klivans, Martin Spanning trees

  19. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Critical group of graphs Critical group of simplicial complexes Spanning trees and the critical group of simplicial complexes Art Duval1 of Kansas Mathematics Seminar Reed College April 28, 2011 Duval, Klivans, Martin Spanning trees

  20. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Complete colorful complexes Weighted spanning tree enumerators of complete colorful complexes Ghodratollah Aalipour1,2 Art Duval1 1 April 21, 2013 Ghodratollah Aalipour, Art Duval Spanning tree enumerators of complete colorful complexes

  1. Discordance of Species Trees with Their Most Likely Gene Trees

    E-print Network

    Rosenberg, Noah

    Discordance of Species Trees with Their Most Likely Gene Trees James H. Degnan1 , Noah A. Rosenberg way in which lineages sort during speciation, gene trees may differ in topology from each other and from species trees. Surprisingly, assuming that genetic lineages follow a coalescent model of within

  2. Spanning trees of graphs Spanning trees of simplicial complexes

    E-print Network

    Duval, Art

    Spanning trees of graphs Spanning trees of simplicial complexes Complete colorful complexes Weighted spanning tree enumerators of complete colorful complexes Ghodratollah Aalipour1,2 Art Duval1 1 of Mississippi March 2, 2013 Ghodratollah Aalipour, Art Duval Spanning tree enumerators of complete colorful

  3. 44 TREE CARE INDUSTRY -MARCH 2002 Tree&Landscape

    E-print Network

    Schweik, Charles M.

    44 TREE CARE INDUSTRY - MARCH 2002 Tree&Landscape 44 II nstallation of underground irrigation green in more ways than one. From keeping trees healthy to providing a viable source of income to their clients. Improved soil con- ditions for tree growth can be achieved using irrigation, and state

  4. Evolutionary tree reconstruction

    NASA Technical Reports Server (NTRS)

    Cheeseman, Peter; Kanefsky, Bob

    1990-01-01

    It is described how Minimum Description Length (MDL) can be applied to the problem of DNA and protein evolutionary tree reconstruction. If there is a set of mutations that transform a common ancestor into a set of the known sequences, and this description is shorter than the information to encode the known sequences directly, then strong evidence for an evolutionary relationship has been found. A heuristic algorithm is described that searches for the simplest tree (smallest MDL) that finds close to optimal trees on the test data. Various ways of extending the MDL theory to more complex evolutionary relationships are discussed.

  5. Learning classification trees

    NASA Technical Reports Server (NTRS)

    Buntine, Wray

    1991-01-01

    Algorithms for learning classification trees have had successes in artificial intelligence and statistics over many years. How a tree learning algorithm can be derived from Bayesian decision theory is outlined. This introduces Bayesian techniques for splitting, smoothing, and tree averaging. The splitting rule turns out to be similar to Quinlan's information gain splitting rule, while smoothing and averaging replace pruning. Comparative experiments with reimplementations of a minimum encoding approach, Quinlan's C4 and Breiman et al. Cart show the full Bayesian algorithm is consistently as good, or more accurate than these other approaches though at a computational price.

  6. The Average Height of Binary Trees and Other Simple Trees

    Microsoft Academic Search

    Philippe Flajolet; Andrew M. Odlyzko

    1982-01-01

    The average height of a binary tree with n internal nodes is shown to be asymptotic to 2 6. This represents the average stack height of the simplest recursive tree traversal algorithm. The method used in this estimation is also applicable to the analysis of traversal algorithms of unary-binary trees, unbalanced 2-3 trees, t-ary trees for any t, and other

  7. Carbon Sequestration in Campus Trees

    NSDL National Science Digital Library

    Robert S. Cole

    In this activity, students use a spreadsheet to calculate the net carbon sequestration in a set of trees; they will utilize an allometric approach based upon parameters measured on the individual trees. They determine the species of trees in the set, measure trunk diameter at a particular height, and use the spreadsheet to calculate carbon content of the tree using forestry research data.

  8. A future with broadleaved trees

    E-print Network

    A future with broadleaved trees A strategy for the Improvement of broadleaved trees in Britain and Ireland 2013-2025 Supported by #12;2 A future with broAdleAved trees Many people and organisations from and highlights areas where we believe further consideration is required. Future Trees Trust, Earth Trust

  9. COMPONENT User's Guide Consensus trees

    E-print Network

    Page, Roderic

    COMPONENT User's Guide Chapter 4 Consensus trees Consensus trees are a convenient way to summarise the agreement between two or more trees. This chapter describes the consensus methods available in COMPONENT subtree (Kubicka et al, 1992; also called the common pruned tree [Finden and Gordon, 1985]). This method

  10. Verticillium Wilt of Shade Trees

    E-print Network

    , resulting in blockage of water movement from the roots to the foliage. The tree responds to infection recurrence of the trouble. NOTE: Yews and conifers are resistant to Verticillium wilt. Redbud and smoke tree Sassafras Boxwood Horse chestnut Serviceberry Brambles Japanese pagoda tree Smoke tree Buckeye Lilac Sumac

  11. Tree of Hexagons

    NSDL National Science Digital Library

    2011-01-01

    In this activity students use measuring skills and follow directions to make a three-dimensional ornament. Learners construct hexagons of graduated sizes from circles and assemble them into a tree. Complete instructions are provided.

  12. Life of a Tree

    NSDL National Science Digital Library

    2007-08-09

    In this interactive activity adapted from the National Arbor Day Foundation, take a sixty-two-year journey observing the inner layers, rings, and environmental factors that affect a tree's growth and life cycle.

  13. Combining Binary Search Trees

    E-print Network

    Demaine, Erik D.

    We present a general transformation for combining a constant number of binary search tree data structures (BSTs) into a single BST whose running time is within a constant factor of the minimum of any “well-behaved” bound ...

  14. Generalized constructive tree weights

    NASA Astrophysics Data System (ADS)

    Rivasseau, Vincent; Tanasa, Adrian

    2014-04-01

    The Loop Vertex Expansion (LVE) is a quantum field theory (QFT) method which explicitly computes the Borel sum of Feynman perturbation series. This LVE relies in a crucial way on symmetric tree weights which define a measure on the set of spanning trees of any connected graph. In this paper we generalize this method by defining new tree weights. They depend on the choice of a partition of a set of vertices of the graph, and when the partition is non-trivial, they are no longer symmetric under permutation of vertices. Nevertheless we prove they have the required positivity property to lead to a convergent LVE; in fact we formulate this positivity property precisely for the first time. Our generalized tree weights are inspired by the Brydges-Battle-Federbush work on cluster expansions and could be particularly suited to the computation of connected functions in QFT. Several concrete examples are explicitly given.

  15. Generalized constructive tree weights

    SciTech Connect

    Rivasseau, Vincent, E-mail: vincent.rivasseau@th.u-psud.fr, E-mail: adrian.tanasa@ens-lyon.org [LPT, CNRS UMR 8627, Univ. Paris 11, 91405 Orsay Cedex, France and Perimeter Institute for Theoretical Physics, 31 Caroline St. N, Ontario N2L 2Y5, Waterloo (Canada)] [LPT, CNRS UMR 8627, Univ. Paris 11, 91405 Orsay Cedex, France and Perimeter Institute for Theoretical Physics, 31 Caroline St. N, Ontario N2L 2Y5, Waterloo (Canada); Tanasa, Adrian, E-mail: vincent.rivasseau@th.u-psud.fr, E-mail: adrian.tanasa@ens-lyon.org [Université Paris 13, Sorbonne Paris Cité, 99, Avenue Jean-Baptiste Clément LIPN, Institut Galilée, CNRS UMR 7030, F-93430 Villetaneuse, France and Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O.B. MG-6, 077125 Magurele (Romania)] [Université Paris 13, Sorbonne Paris Cité, 99, Avenue Jean-Baptiste Clément LIPN, Institut Galilée, CNRS UMR 7030, F-93430 Villetaneuse, France and Horia Hulubei National Institute for Physics and Nuclear Engineering, P.O.B. MG-6, 077125 Magurele (Romania)

    2014-04-15

    The Loop Vertex Expansion (LVE) is a quantum field theory (QFT) method which explicitly computes the Borel sum of Feynman perturbation series. This LVE relies in a crucial way on symmetric tree weights which define a measure on the set of spanning trees of any connected graph. In this paper we generalize this method by defining new tree weights. They depend on the choice of a partition of a set of vertices of the graph, and when the partition is non-trivial, they are no longer symmetric under permutation of vertices. Nevertheless we prove they have the required positivity property to lead to a convergent LVE; in fact we formulate this positivity property precisely for the first time. Our generalized tree weights are inspired by the Brydges-Battle-Federbush work on cluster expansions and could be particularly suited to the computation of connected functions in QFT. Several concrete examples are explicitly given.

  16. Tree-bank grammars

    SciTech Connect

    Charniak, E. [Brown Univ., Providence, RI (United States)

    1996-12-31

    By a {open_quotes}tree-bank grammar{close_quotes} we mean a context-free grammar created by reading the production rules directly from hand-parsed sentences in a tree bank. Common wisdom has it that such grammars do not perform well, though we know of no published data on the issue. The primary purpose of this paper is to show that the common wisdom is wrong. In particular, we present results on a tree-bank grammar based on the Penn Wall Street Journal tree bank. To the best of our knowledge, this grammar outperforms all other non-word-based statistical parsers/grammars on this corpus. That is, it outperforms parsers that consider the input as a string of tags and ignore the actual words of the corpus.

  17. Peach Tree Pruning.

    E-print Network

    Lyons, Calvin G.

    1986-01-01

    Pa..e ln ~O~BldletinJ . -/., .~ . :~. ' .:' .; f.' ):, . ~- :: ; ',': } . .. ~ '::, PEACH TREE PRUNING Calvin G. Lyons* Peaches are pruned in several ways in the U.S. depending on the area, rainfall, grower preference and tradition...

  18. Tree nut allergy

    Microsoft Academic Search

    Suzanne S. Teuber; Sarah S. Comstock; Shridhar K. Sathe; Kenneth H. Roux

    2003-01-01

    Tree nuts are clinically associated with severe immunoglobulin E-mediated systemic allergic reactions independent of pollen\\u000a allergy and with reactions that are usually confined to the oral mucosa in patients with immunoglobulin E directed toward\\u000a cross-reacting pollen allergens. The latter reactions can progress to severe and life-threatening episodes in some patients.\\u000a Many patients with severe tree nut allergy are co-sensitized to

  19. Core Based Trees (CBT)

    Microsoft Academic Search

    Tony Ballardie; Paul Francis; Jon Crowcroft

    1993-01-01

    One of the central problems in one-to-many wide-area communications is forming the delivery tree - the collection of nodes and links that a multicast packet traverses. Significant problems remain to be solved in the area of multicast tree formation, the problem of scaling being paramount among these.In this paper we show how the current IP multicast architecture scales poorly (by

  20. The Ubiquitous B-Tree

    Microsoft Academic Search

    Douglas E. Comer

    1979-01-01

    B-trees have become, de facto, a standard for file organization. File indexes of users, dedicated database systems, and general-purpose access methods have all been proposed and implemented using B-trees. This paper reviews B-trees and shows why they have been so successful. It discusses the major variations of the B-tree, especially the W-tree, contrasting the relative merits and costs of each

  1. The Inference of Gene Trees with Species Trees

    PubMed Central

    Szöll?si, Gergely J.; Tannier, Eric; Daubin, Vincent; Boussau, Bastien

    2015-01-01

    This article reviews the various models that have been used to describe the relationships between gene trees and species trees. Molecular phylogeny has focused mainly on improving models for the reconstruction of gene trees based on sequence alignments. Yet, most phylogeneticists seek to reveal the history of species. Although the histories of genes and species are tightly linked, they are seldom identical, because genes duplicate, are lost or horizontally transferred, and because alleles can coexist in populations for periods that may span several speciation events. Building models describing the relationship between gene and species trees can thus improve the reconstruction of gene trees when a species tree is known, and vice versa. Several approaches have been proposed to solve the problem in one direction or the other, but in general neither gene trees nor species trees are known. Only a few studies have attempted to jointly infer gene trees and species trees. These models account for gene duplication and loss, transfer or incomplete lineage sorting. Some of them consider several types of events together, but none exists currently that considers the full repertoire of processes that generate gene trees along the species tree. Simulations as well as empirical studies on genomic data show that combining gene tree–species tree models with models of sequence evolution improves gene tree reconstruction. In turn, these better gene trees provide a more reliable basis for studying genome evolution or reconstructing ancestral chromosomes and ancestral gene sequences. We predict that gene tree–species tree methods that can deal with genomic data sets will be instrumental to advancing our understanding of genomic evolution. PMID:25070970

  2. The inference of gene trees with species trees.

    PubMed

    Szöll?si, Gergely J; Tannier, Eric; Daubin, Vincent; Boussau, Bastien

    2015-01-01

    This article reviews the various models that have been used to describe the relationships between gene trees and species trees. Molecular phylogeny has focused mainly on improving models for the reconstruction of gene trees based on sequence alignments. Yet, most phylogeneticists seek to reveal the history of species. Although the histories of genes and species are tightly linked, they are seldom identical, because genes duplicate, are lost or horizontally transferred, and because alleles can coexist in populations for periods that may span several speciation events. Building models describing the relationship between gene and species trees can thus improve the reconstruction of gene trees when a species tree is known, and vice versa. Several approaches have been proposed to solve the problem in one direction or the other, but in general neither gene trees nor species trees are known. Only a few studies have attempted to jointly infer gene trees and species trees. These models account for gene duplication and loss, transfer or incomplete lineage sorting. Some of them consider several types of events together, but none exists currently that considers the full repertoire of processes that generate gene trees along the species tree. Simulations as well as empirical studies on genomic data show that combining gene tree-species tree models with models of sequence evolution improves gene tree reconstruction. In turn, these better gene trees provide a more reliable basis for studying genome evolution or reconstructing ancestral chromosomes and ancestral gene sequences. We predict that gene tree-species tree methods that can deal with genomic data sets will be instrumental to advancing our understanding of genomic evolution. PMID:25070970

  3. In this chapter we study infinite trees. The main things we look at are Konig's tree theorem, Aronszajn trees, and Suslin trees.

    E-print Network

    Monk, Don

    8. Trees In this chapter we study infinite trees. The main things we look at are K¨onig's tree theorem, Aronszajn trees, and Suslin trees. A tree is a partially ordered set (T, t T, the set {s T : s tree

  4. In this chapter we study infinite trees. The main things we look at are Konig's tree theorem, Aronszajn trees, and Suslin trees.

    E-print Network

    Monk, Don

    14. Trees In this chapter we study infinite trees. The main things we look at are K¨onig's tree theorem, Aronszajn trees, and Suslin trees. A tree is a partially ordered set (T, t T, the set {s T : s tree

  5. Nearest tree Always go to the closest

    E-print Network

    Nearest tree Always go to the closest tree Largest tree Always go to the tree with the most apples Optimal 1-step forager Maximize rate (= ratio of apples to travel time), but only consider one tree at a time # apples travel time Optimal 2-, 3-step forager Maximize rate over 2-tree (or 3-tree) paths

  6. A Parallel Tree Code

    E-print Network

    John Dubinski

    1996-03-18

    We describe a new implementation of a parallel N-body tree code. The code is load-balanced using the method of orthogonal recursive bisection to subdivide the N-body system into independent rectangular volumes each of which is mapped to a processor on a parallel computer. On the Cray T3D, the load balance in the range of 70-90\\% depending on the problem size and number of processors. The code can handle simulations with $>$ 10 million particles roughly a factor of 10 greater than allowed in vectorized tree codes.

  7. The Tree of Life

    NSDL National Science Digital Library

    David R. Maddison

    2007-12-12

    The Tree of Life is a collection of about 2000 World Wide Web pages containing information about the diversity of life. These pages are authored by biologists from around the world... Each page contains information about one group of organisms. The pages are linked one to another in the form of the evolutionary tree of organisms, with the pages branching off from a group's page being about subgroups. This vast site contains a large collection of biological images, most of which can be reproduced and used for educational purposes. Since some of the topics are controversial in nature, an attempt is made to present all sides of the issue. References are included.

  8. Gene trees and species trees are not the same

    Microsoft Academic Search

    Richard Nichols

    2001-01-01

    The relationship between species is usually represented as a bifurcating tree with the branching points representing speciation events. The ancestry of genes taken from these species can also be represented as a tree, with the branching points representing ancestral genes. The time back to the branching points, and even the branching order, can be different between the two trees. This

  9. Classify the trees/Leaves

    NSDL National Science Digital Library

    Mary Walsh

    This activity is a field investigation where students gather leaves from various trees on school property, interpret findings, name tree and leaves, journal activity and develop a new "aha" for nature!

  10. Hierarchy and Tree Visualization

    E-print Network

    Yang, Jing

    Vis 01 #12;6 3D Approach 2 - Cone Tree 11 Robertson, Mackinlay, Card CHI `91 Advantages vs. Limitations-3 generations from current node Smooth animation for change in focus Don't draw objects when far enough from on the surface of a hemisphere like sprinkles on an ice creamhemisphere like sprinkles on an ice cream cone. 24

  11. Tree Unification Grammar

    Microsoft Academic Search

    Kim Gerdes

    2004-01-01

    This work presents a lexicalized grammar formalism which can be seen as a variant of multi-component tree adjoining grammar (TAG). This formalism is well-suited for describing the syntax of German because it relates a syntactic dependency graph with a hierarchy of topological domains. The topological phrase structure encodes the placement of verbal and nominal elements in the (ordered) field structure,

  12. Arbutus unedo, Strawberry Tree

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Encylopedia of Fruit and Nuts is designed as a research reference source on temperate and tropical fruit and nut crops. Strawberry tree or madrone is native to the Mediterranean region of southern Europe (Arbutus unedo L., Ericaceae) with a relict population in Ireland, as well as in North Ameri...

  13. Tree Nut Allergens

    Microsoft Academic Search

    Kenneth H. Roux; Suzanne S. Teuber; Shridhar K. Sathe

    2003-01-01

    Allergic reactions to tree nuts can be serious and life threatening. Considerable research has been conducted in recent years in an attempt to characterize those allergens that are most responsible for allergy sensitization and triggering. Both native and recombinant nut allergens have been identified and characterized and, for some, the IgE-reactive epitopes described. Some allergens, such as lipid transfer proteins,

  14. Tree-Ties.

    ERIC Educational Resources Information Center

    Gresczyk, Rick

    Created to help students understand how plants were used for food, for medicine, and for arts and crafts among the Ojibwe (Chippewa) Indians, the game Tree-Ties combines earth and social sciences within a specific culture. The game requires mutual respect, understanding, and agreement to succeed. Sounding like the word "treaties", the title is a…

  15. Tree Fertilization Soil Analysis

    E-print Network

    Tree Fertilization #12;Soil Analysis vs. Foliar Analysis #12;Macronutrients N P K Mg S Ca Micronutrients Fe Mn Zn Mo Cu Cl B #12;Complete fertilizer N P K #12;Fertilizer Analysis Percentages of N P K #12;ANSI A-300 Fertilizer Standard Standards are used to develop contract specifications. Fertilize

  16. Digging Deeper with Trees.

    ERIC Educational Resources Information Center

    Growing Ideas, 2001

    2001-01-01

    Describes hands-on science areas that focus on trees. A project on leaf pigmentation involves putting crushed leaves in a test tube with solvent acetone to dissolve pigment. In another project, students learn taxonomy by sorting and classifying leaves based on observable characteristics. Includes a language arts connection. (PVD)

  17. Phylogenics & Tree-Thinking

    ERIC Educational Resources Information Center

    Baum, David A.; Offner, Susan

    2008-01-01

    Phylogenetic trees, which are depictions of the inferred evolutionary relationships among a set of species, now permeate almost all branches of biology and are appearing in increasing numbers in biology textbooks. While few state standards explicitly require knowledge of phylogenetics, most require some knowledge of evolutionary biology, and many…

  18. Induction of decision trees

    Microsoft Academic Search

    J. Ross Quinlan

    1986-01-01

    The technology for building knowledge-based systems by inductive inference from examples has been demonstrated successfully in several practical applications. This paper summarizes an approach to synthesizing decision trees that has been used in a variety of systems, and it describes one such system, ID3, in detail. Results from recent studies show ways in which the methodology can be modified to

  19. The Sacred Tree.

    ERIC Educational Resources Information Center

    Lethbridge Univ. (Alberta).

    Designed as a text for high school students and adults, this illustrated book presents ethical concepts and teachings of Native societies throughout North America concerning the nature and possibilities of human existence. The final component of a course in self-discovery and development, the book begins with the legend of the "Sacred Tree

  20. Sizing Up Trees.

    ERIC Educational Resources Information Center

    Nelson, Don

    1995-01-01

    Presents a way for teachers to capitalize on children's intrinsic fascination with big things by measuring the world's largest living plants--trees. Students develop an appreciation of nature, work together cooperatively, and practice science process skills. Outlines the procedure and equipment including pencils, metersticks, and string. (NB)

  1. Umdhlebi Tree of Zululand

    Microsoft Academic Search

    G. W. Parker

    1882-01-01

    There are two species, in both the leaf is lanceolate, dark green, glossy, hard, and brittle, and from both a thick milky juice exudes, while the fruit is like a long black pod, red at the end. One species is a tree with large leaves, and peculiar looking stem, the bark hanging down in large flakes, showing a fresh growth

  2. Game Trees for Decision Analysis

    E-print Network

    Shenoy, Prakash P.

    1998-04-01

    Game trees (or extensive-form games) were first defined by von Neumann and Morgenstern in 1944. In this paper, we examine the use of game trees for representing Bayesian decision problems. We propose a method for solving game trees using local...

  3. Selecting Trees for Community Landscapes

    Microsoft Academic Search

    Henry D. Gerhold; William Porter

    Selecting the most appropriate trees for various kinds of planting sites is crucial for the success of a municipal tree program. A properly selected tree will appreciate in value for a long time and will be cherished by many people. Conversely, an improper choice might soon become unhealthy or die. Even worse, problems could appear years later when a remedy

  4. Trees and Dags An Introduction

    E-print Network

    Andrews, Peter B.

    Chapter 5 Trees and Dags An Introduction to Separation Logic c #2007 John C. Reynolds February 28, 2007 In this chapter, we consider various representations of abstract tree­like data. In general­expressions are the initial lawless algebra with an infinite number of constants and one binary operation.) 5.1 Trees We use

  5. Qualitative Tree Languages Arnaud Carayol

    E-print Network

    Paris-Sud XI, Université de

    Qualitative Tree Languages Arnaud Carayol LIGM (Univ. Paris Est & CNRS) Arnaud) Olivier.Serre@liafa.jussieu.fr Abstract--We study finite automata running over infinite binary trees) of non-accepting branches. In this qualitative setting, a tree is accepted by the automaton

  6. The Hopi Fruit Tree Book.

    ERIC Educational Resources Information Center

    Nyhuis, Jane

    Referring as often as possible to traditional Hopi practices and to materials readily available on the reservation, the illustrated booklet provides information on the care and maintenance of young fruit trees. An introduction to fruit trees explains the special characteristics of new trees, e.g., grafting, planting pits, and watering. The…

  7. Our Air: Unfit for Trees.

    ERIC Educational Resources Information Center

    Dochinger, Leon S.

    To help urban, suburban, and rural tree owners know about air pollution's effects on trees and their tolerance and intolerance to pollutants, the USDA Forest Service has prepared this booklet. It answers the following questions about atmospheric pollution: Where does it come from? What can it do to trees? and What can we do about it? In addition,…

  8. Bag Context Tree Grammars # Sigrid Ewert

    E-print Network

    Drewes, Frank

    or string, but evolves on its own during a derivation. Motivation for investigating bag context tree an investigation into random context in tree gram­ mars and tree transducers. A random context tree grammar G, of course, is that in developing a path of a tree, one has to be aware of the whole of the evolving tree

  9. Binary search trees of bounded balance

    Microsoft Academic Search

    Jürg Nievergelt; Edward M. Reingold

    1972-01-01

    A new class of binary search trees, called trees of bounded balance, is introduced. These trees are easy to maintain in their form despite insertions and deletions of nodes, and the search time is only moderately longer than in completely balanced trees. Trees of bounded balance differ from other classes of binary search trees in that they contain a parameter

  10. Red-black Tree Jingjing Xia

    E-print Network

    Chen, Yangjun

    Advanced Algorithm Design Red-black Tree Jingjing Xia #12;Red-Black Tree A red-black tree is a binary search tree, and each node contains one extra field: its color, it can be either black or red of the binary search tree. If a binary search tree satisfies all the following red-black properties, it is a red

  11. PoInTree: a polar and interactive phylogenetic tree.

    PubMed

    Carreras, Marco; Marco, Cerreras; Gianti, Eleonora; Eleonora, Gianti; Sartori, Luca; Luca, Sartori; Plyte, Simon Edward; Edward, Plyte Simon; Isacchi, Antonella; Antonella, Isacchi; Bosotti, Roberta; Roberta, Bosotti

    2005-02-01

    PoInTree (Polar and Interactive Tree) is an application that allows to build, visualize and customize phylogenetic trees in a polar interactive and highly flexible view. It takes as input a FASTA file or multiple alignment formats. Phylogenetic tree calculation is based on a sequence distance method and utilizes the Neighbor Joining (NJ) algorithm. It also allows displaying precalculated trees of the major protein families based on Pfam classification. In PoInTree, nodes can be dynamically opened and closed and distances between genes are graphically represented. Tree root can be centered on a selected leaf. Text search mechanism, color-coding and labeling display are integrated. The visualizer can be connected to an Oracle database containing information on sequences and other biological data, helping to guide their interpretation within a given protein family across multiple species. The application is written in Borland Delphi and based on VCL Teechart Pro 6 graphical component (Steema software). PMID:16144524

  12. Rate of tree carbon accumulation increases continuously with tree size.

    PubMed

    Stephenson, N L; Das, A J; Condit, R; Russo, S E; Baker, P J; Beckman, N G; Coomes, D A; Lines, E R; Morris, W K; Rüger, N; Alvarez, E; Blundo, C; Bunyavejchewin, S; Chuyong, G; Davies, S J; Duque, A; Ewango, C N; Flores, O; Franklin, J F; Grau, H R; Hao, Z; Harmon, M E; Hubbell, S P; Kenfack, D; Lin, Y; Makana, J-R; Malizia, A; Malizia, L R; Pabst, R J; Pongpattananurak, N; Su, S-H; Sun, I-F; Tan, S; Thomas, D; van Mantgem, P J; Wang, X; Wiser, S K; Zavala, M A

    2014-03-01

    Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations. Our ability to understand and predict changes in the forest carbon cycle--particularly net primary productivity and carbon storage--increasingly relies on models that represent biological processes across several scales of biological organization, from tree leaves to forest stands. Yet, despite advances in our understanding of productivity at the scales of leaves and stands, no consensus exists about the nature of productivity at the scale of the individual tree, in part because we lack a broad empirical assessment of whether rates of absolute tree mass growth (and thus carbon accumulation) decrease, remain constant, or increase as trees increase in size and age. Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size. Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree. The apparent paradoxes of individual tree growth increasing with tree size despite declining leaf-level and stand-level productivity can be explained, respectively, by increases in a tree's total leaf area that outpace declines in productivity per unit of leaf area and, among other factors, age-related reductions in population density. Our results resolve conflicting assumptions about the nature of tree growth, inform efforts to undertand and model forest carbon dynamics, and have additional implications for theories of resource allocation and plant senescence. PMID:24429523

  13. Gene tree correction for reconciliation and species tree inference

    PubMed Central

    2012-01-01

    Background Reconciliation is the commonly used method for inferring the evolutionary scenario for a gene family. It consists in “embedding” inferred gene trees into a known species tree, revealing the evolution of the gene family by duplications and losses. When a species tree is not known, a natural algorithmic problem is to infer a species tree from a set of gene trees, such that the corresponding reconciliation minimizes the number of duplications and/or losses. The main drawback of reconciliation is that the inferred evolutionary scenario is strongly dependent on the considered gene trees, as few misplaced leaves may lead to a completely different history, with significantly more duplications and losses. Results In this paper, we take advantage of certain gene trees’ properties in order to preprocess them for reconciliation or species tree inference. We flag certain duplication vertices of a gene tree, the “non-apparent duplication” (NAD) vertices, as resulting from the misplacement of leaves. In the case of species tree inference, we develop a polynomial-time heuristic for removing the minimum number of species leading to a set of gene trees that exhibit no NAD vertices with respect to at least one species tree. In the case of reconciliation, we consider the optimization problem of removing the minimum number of leaves or species leading to a tree without any NAD vertex. We develop a polynomial-time algorithm that is exact for two special classes of gene trees, and show a good performance on simulated data sets in the general case. PMID:23167951

  14. From Gene to Organismal Phylogeny: Reconciled Trees and the Gene Tree/Species Tree Problem

    E-print Network

    Page, Roderic

    From Gene to Organismal Phylogeny: Reconciled Trees and the Gene Tree/Species Tree Problem Roderic The processes of gene duplication, loss, and lineage sorting can result in incongruence between the phylog- enies of genes and those of species. This incongruence complicates the task of inferring the latter from

  15. Hasse Diagrams for Classes of Deterministic Bottom-Up Tree-to-Tree-Series

    E-print Network

    Reyle, Uwe

    Hasse Diagrams for Classes of Deterministic Bottom-Up Tree-to-Tree-Series Transformations Andreas The relationship between classes of tree-to-tree-series and o-tree-to-tree-series trans- formations, which are computed by restricted deterministic bottom-up weighted tree transducers, is investigated. Essentially

  16. Global Value Trees

    PubMed Central

    Zhu, Zhen; Puliga, Michelangelo; Cerina, Federica; Chessa, Alessandro; Riccaboni, Massimo

    2015-01-01

    The fragmentation of production across countries has become an important feature of the globalization in recent decades and is often conceptualized by the term “global value chains” (GVCs). When empirically investigating the GVCs, previous studies are mainly interested in knowing how global the GVCs are rather than how the GVCs look like. From a complex networks perspective, we use the World Input-Output Database (WIOD) to study the evolution of the global production system. We find that the industry-level GVCs are indeed not chain-like but are better characterized by the tree topology. Hence, we compute the global value trees (GVTs) for all the industries available in the WIOD. Moreover, we compute an industry importance measure based on the GVTs and compare it with other network centrality measures. Finally, we discuss some future applications of the GVTs. PMID:25978067

  17. 2-4 Trees and B-Trees To know what a 2-4 tree is (9.1).

    E-print Network

    Liang, Y. Daniel

    809 CHAPTER 9 2-4 Trees and B-Trees Objectives · To know what a 2-4 tree is (§9.1). · To design the Tree24 class that implements the Tree interface (§9.2). · To search an element in a 2-4 tree (§9.3). · To insert an element in a 2-4 tree and know how to split a node (§9.4). · To delete an element from a 2

  18. PALM TREE GROVE COLLEGEAVE.

    E-print Network

    Fernandez, Eduardo

    PALM TREE GROVE LAKE LAKE COLLEGEAVE. SW 30th ST. DAVIEROAD DAVIEROAD ACCESS RD. ACCESSRD. SW64thAVE. LAKE LAKE LAKE BC54 BC50 BC49 27 36 BC52 BC53 BC51 BC17 BC90 BC91 COLLEGEAVE. POOL POOL 3200 College Avenue, Davie, FL 33314 LEGEND BLDG. # BUILDING NAME BC17 (LY) BC49 (LA) BC50 (CH) BC51 (WL) BC52 (ES) BC

  19. Optimal search in trees

    SciTech Connect

    Ben-Asher, Y.; Newman, I. [Haifa Univ. (Israel); Farchi, E. [IBM Research Center, Haifa (Israel)

    1997-06-01

    It is well known that the optimal solution for searching in a finite total order set is the binary search. In binary search we divide the set into two {open_quotes}halves{close_quotes}, by querying the middle element, and continue the search on the suitable half. What is the equivalent of binary search, when the set P is partially ordered? A query in this case is to a point x {element_of} P, with two possible answers:{open_quote}yes{close_quote}, indicates that the required element is {open_quotes}below{close_quotes} x, or {open_quote}no{close_quote} if the element is not bellow x. We show that the problem of computing an optimal strategy for search in Posets that are tree-like (or forests) is polynomial in the size of the tree, and requires at most O(n{sup 2} log{sup 2} n) steps. Optimal solutions of such search problems are often needed in program testing and debugging, where a given program is represented as a tree and a bug should be found using a minimal set of queries.

  20. The fault-tree compiler

    NASA Technical Reports Server (NTRS)

    Martensen, Anna L.; Butler, Ricky W.

    1987-01-01

    The Fault Tree Compiler Program is a new reliability tool used to predict the top event probability for a fault tree. Five different gate types are allowed in the fault tree: AND, OR, EXCLUSIVE OR, INVERT, and M OF N gates. The high level input language is easy to understand and use when describing the system tree. In addition, the use of the hierarchical fault tree capability can simplify the tree description and decrease program execution time. The current solution technique provides an answer precise (within the limits of double precision floating point arithmetic) to the five digits in the answer. The user may vary one failure rate or failure probability over a range of values and plot the results for sensitivity analyses. The solution technique is implemented in FORTRAN; the remaining program code is implemented in Pascal. The program is written to run on a Digital Corporation VAX with the VMS operation system.

  1. Pseudo-Gilbert-Steiner trees

    Microsoft Academic Search

    Dan Trietsch; J. F. Weng

    1999-01-01

    The Gilbert network problem is a generalization of the Steiner minimal tree problem derived by adding flow-dependent weights to the edges. In this paper, we define a special class of minimum Gilbert networks, called pseudo-Gilbert-Steiner trees, and we show that it can be constructed by Gilbert's generalization of Melzak's method. Besides, a counterexample, a pseudo-Gilbert-Steiner tree, is con- structed to

  2. Tree Induction over Perennial Objects

    Microsoft Academic Search

    Zaigham Faraz Siddiqui; Myra Spiliopoulou

    2010-01-01

    \\u000a We study the tree induction over a stream of perennial objects. The perennial objects are dynamic in nature and cannot be forgotten. The objects come from a multi-table stream, e.g., streams of Customer and Transaction. As the Transactions arrive, the perennial Customers’ profiles grow and accumulate over time. To perform tree induction, we propose a tree induction algorithm that can

  3. Polymer oxidation and water treeing

    Microsoft Academic Search

    A. T. Bulinski; J.-P. Crine; B. Noirhomme; R. J. Densley; S. Bamji

    1998-01-01

    In order to determine whether or not oxidation of polymer influences water treeing, more than 200 vented and bow-tie trees from 31 field-aged cables were investigated. Micro-IR spectroscopy analysis has not shown any consistent excess of carbonyl content in water trees as compared with the adjacent non-treed regions of the insulation. Although the levels of carbonyl content of the bulk

  4. Compositional Temporal Fault Tree Analysis

    Microsoft Academic Search

    Martin Walker; Leonardo Bottaci; Yiannis Papadopoulos

    2007-01-01

    HiP-HOPS (Hierarchically-Performed Hazard Origin and Propaga- tion Studies) is a recent technique that partly automates Fault Tree Analysis (FTA) by constructing fault trees from system topologies annotated with component-level failure specifications. HiP-HOPS has hitherto created only classical combinatorial fault trees that fail to capture the often significant temporal ordering of failure events. In this paper, we propose temporal extensions to

  5. Collapse of loaded fractal trees

    NASA Astrophysics Data System (ADS)

    Turcotte, D. L.; Smalley, R. F.; Solla, Sara A.

    1985-02-01

    Mandelbrot1 has argued that a wide range of natural objects and phenomena are fractals; examples of fractal trees include actual trees, plants such as a cauliflower, river systems and the cardiovascular system. Here we apply the renormalization group approach2 to the collapse of fractal trees, which may be applicable to a variety of problems including cardiac arrest, failure of bronchial systems, failure of electrical distribution systems and the instability resulting in earthquakes.

  6. Cellular automata on Cayley tree

    E-print Network

    Hasan Akin

    2012-11-30

    In this paper, we study cellular automata on Cayley tree of order 2 over the field $\\mathbb Z_p$ (the set of prime numbers modulo $p$). We construct the rule matrix corresponding to finite cellular automata on Cayley tree. Further, we analyze the reversibility problem of this cellular automata for some given values of $a,b,c,d\\in \\mathbb{Z}_{p}\\setminus {0}$ and the levels $n$ of Cayley tree. We compute the measure-theoretical entropy of the cellular automata which we define on Cayley tree.

  7. Random Tree Generation for Genetic Programming

    Microsoft Academic Search

    Hitoshi Iba

    1996-01-01

    This paper introduces a random tree generation algorithm for GP (Genetic Programming). Generating random trees is an essential part of GP. However, the recursive method commonly used in GP does not necessarily generate random trees, i.e the standard GP initialization procedure does not sample the space of possible initial trees uniformly. This paper proposes a truly random tree generation procedure

  8. ECONOMIC ANALYSIS OF URBAN TREE REPLACEMENT DECISIONS

    Microsoft Academic Search

    Jessie L. Scott; David R. Betters

    2000-01-01

    A critical decision facing urban foresters, arborists, and planners involves deciding when an existing tree should be removed and replaced with a new plant- ing. Tree removal decisions are often based on an evaluation of the tree's health and condition as well as safety concerns. A tree may be retained, but nor- mally this requires a tree maintenance program and

  9. COMPONENT User's Guide Maps between trees

    E-print Network

    Page, Roderic

    COMPONENT User's Guide Chapter 7 Maps between trees This chapter describes tree mapping routines in COMPONENT. These routines allow you to map gene trees onto species trees, parasite phylogenies onto host phylogenies, and taxon cladograms onto area cladograms. Overview This section introduces some basics of tree

  10. Exploring Trees and Ponds

    NSDL National Science Digital Library

    Trees and Ponds is a collection of activities to be implemented with middle school youth in out-of-school environments. The website provides a rationale and goal of the activities, curriculum activities and resources such as relevant digital photos. Available for free as downloadable PDFs, these activities provide a structure for youth in out-of-school programs to carry out long-term observations of natural objects. This project uses a qualitative approach, where changes over time are studied, recorded (by youth through writing, drawing, and digital photography), and discussed.

  11. Save a Tree

    NASA Astrophysics Data System (ADS)

    Williams, Kathryn R.

    1999-10-01

    Starting in September 1925, JCE reproduced pictures of famous chemists or chemistry-related works of art as frontispieces. Often, the Journal included a biography or other article about the picture. The August 1945 frontispiece featured the largest cork oak in the United States. An accompanying article described the goals of the Cork Project to plant cork trees in suitable locations in the U.S., to compensate for uncertain European and African sources during World War II. The final frontispiece appeared in December 1956. To view supplementary material, please refer to JCE Online's supplementary links.

  12. Tree Level Gauge Mediation

    E-print Network

    Marco Nardecchia; Andrea Romanino; Robert Ziegler

    2009-11-27

    We propose a new scheme in which supersymmetry breaking is communicated to the MSSM sfermions by GUT gauge interactions at the tree level. The (positive) contribution of MSSM fields to $\\text{Str}(\\mathcal{M}^2)$ is automatically compensated by a (negative) contribution from heavy fields. Sfermion masses are flavour universal, thus solving the supersymmetric flavour problem. In the simplest SO(10) embedding, the ratio of different sfermion masses is predicted and differs from mSugra and other schemes, thus making this framework testable at the LHC. Gaugino masses are generated at the loop level but enhanced by model dependent factors.

  13. Ice Roads: Steiner Trees

    NSDL National Science Digital Library

    Tim Bell

    1998-01-01

    In this outdoor activity, learners use pegs (like tent pegs) and string or elastic to simulate drill sites and roads in Northern Canada. Learners are challenged with figuring out how to connect the roads to all the drill sites while keeping the total road length to a minimum. They'll discover that intersections or "Steiner" points provide efficiency between points within a network. Use this activity to introduce learners to computer science themes including Steiner trees, algorithms, and NP-complete problems. Variations, extensions, background information, and solutions are included in the PDF.

  14. Red-Black Trees 1 2004 Goodrich, Tamassia Red-Black Trees

    E-print Network

    Alechina, Natasha

    Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z #12;Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison with its associated (2,4) tree

  15. Do Invasive Trees have a Hydraulic Advantage over Native Trees?

    Microsoft Academic Search

    R B Pratt; R A Black

    2006-01-01

    The hypothesis was tested that invasive trees have hydraulic traits that contribute to their invasive nature. Five pairs of co-occurring invasive and native trees, in mesic habitats, were selected: (1) Tamarix ramosissima and Salix amygdaloides; (2) Robinia pseudoacacia and Alnus rhombifolia (3) Schinus terebinthifolius and Myrica cerifera; (4) Ligustrum sinense and Acer negundo; and (5) Sapium sebiferum and Diospyros virginiana,

  16. A note on reconfiguring tree linkages: trees can lock

    Microsoft Academic Search

    Therese C. Biedl; Erik D. Demaine; Martin L. Demaine; Sylvain Lazard; Anna Lubiw; Joseph O'rourke; Steve Robbins; Ileana Streinu; Godfried T. Toussaint; Sue Whitesides

    2002-01-01

    It has recently been shown that any polygonal chain in the plane can be reconfigured to lie on a straight line, and any polygon can be reconfigured to be convex. This result cannot be extended to tree linkages: we show that there are trees with two configurations that are not connected by a motion. Indeed, we prove that an N-link

  17. TREE SPACING AND CONTROL OF AVOCADO TREE GROWTH

    Microsoft Academic Search

    Robert G. Platt

    Spacing, training, control of tree growth and orchard thinning are subjects that have been debated by avocado growers for many years. The variability in tree response resulting from the differences between varieties and the influences of soil and climate make broad generalizations difficult. Each situation must be evaluated on its individual requirements. The primary objective of the avocado grower is

  18. Reconciling a Gene Tree to a Species Tree Under the Duplication Paola Bonizzoni

    E-print Network

    Della Vedova, Gianluca

    Reconciling a Gene Tree to a Species Tree Under the Duplication Cost Model Paola Bonizzoni Gianluca from evolutionary trees representing the relationships between distinct gene families is of great of minimum tree that reconciles a gene tree and a species tree is correct. We answer affirmatively

  19. iGLASS: An Improvement to the GLASS Method for Estimating Species Trees from Gene Trees

    E-print Network

    Rosenberg, Noah

    iGLASS: An Improvement to the GLASS Method for Estimating Species Trees from Gene Trees ETHAN M. JEWETT and NOAH A. ROSENBERG ABSTRACT Several methods have been designed to infer species trees from gene trees while taking into account gene tree/species tree discordance. Although some of these methods

  20. Non-crossing Trees are Almost Conditioned Galton-Watson trees1

    E-print Network

    Marckert, Jean-François

    Non-crossing Trees are Almost Conditioned Galton-Watson trees1 Jean-Fran¸cois Marckert Alois-10, A - 1040 Wien, Austria alois.panholzer@tuwien.ac.at ABSTRACT: A non-crossing tree (NC-tree) is a tree drawn seg- ments that do not cross. In this paper, we show that NC-trees with size n are conditioned Galton

  1. Distributed Merge Trees

    SciTech Connect

    Morozov, Dmitriy; Weber, Gunther

    2013-01-08

    Improved simulations and sensors are producing datasets whose increasing complexity exhausts our ability to visualize and comprehend them directly. To cope with this problem, we can detect and extract significant features in the data and use them as the basis for subsequent analysis. Topological methods are valuable in this context because they provide robust and general feature definitions. As the growth of serial computational power has stalled, data analysis is becoming increasingly dependent on massively parallel machines. To satisfy the computational demand created by complex datasets, algorithms need to effectively utilize these computer architectures. The main strength of topological methods, their emphasis on global information, turns into an obstacle during parallelization. We present two approaches to alleviate this problem. We develop a distributed representation of the merge tree that avoids computing the global tree on a single processor and lets us parallelize subsequent queries. To account for the increasing number of cores per processor, we develop a new data structure that lets us take advantage of multiple shared-memory cores to parallelize the work on a single node. Finally, we present experiments that illustrate the strengths of our approach as well as help identify future challenges.

  2. 7 CFR 1214.3 - Christmas tree.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Christmas tree. 1214.3 Section 1214.3 Agriculture...DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information...

  3. 7 CFR 1214.3 - Christmas tree.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Christmas tree. 1214.3 Section 1214.3 Agriculture...DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information...

  4. 7 CFR 1214.3 - Christmas tree.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Christmas tree. 1214.3 Section 1214.3 Agriculture...DEPARTMENT OF AGRICULTURE CHRISTMAS TREE PROMOTION, RESEARCH, AND INFORMATION ORDER Christmas Tree Promotion, Research, and Information...

  5. Genetic conservation of native trees

    E-print Network

    Genetic conservation of native trees Scott McG. Wilson1 and C. J. A. Samuel Over recent years, the genetic conservation of British native tree populations has become an increasingly important part policy-makers in the genetic basis of forest biodiversity conservation, both at the UK and, more

  6. Elemental composition of tree nuts

    Microsoft Academic Search

    A. Keith Furr; Laurence H. MacDaniels; Leigh E. St. John; Walter H. Gutenmann; Irene S. Pakkala; Donald J. Lisk

    1979-01-01

    Growing nut trees is becoming ever more popular among home gardeners and publications dealing with their culture have recently appeared (JAYNES 1969, MACDANIELS 1976). Data on the elemental composition of nuts is very limited with values reported for only a few elements (LISK 1972). Several other publications have dealt with the detection of elements in various tree parts but not

  7. Tree health update Sarah Green

    E-print Network

    of the park in November 2010 revealed: · 63 dead Lawson cypress · 19 dying Lawson cypress · 8 dead yew trees · 19 dying yew trees · 20+ hedgerow yew dead · Need for rapid diagnosis #12;25/03/20119 Basal lesions stem kill phloem and disrupt xylem, cause crown death · Less than 2200 Ha of commercially grown Lawson

  8. Water treeing and polymer oxidation

    Microsoft Academic Search

    R. J. Densley; S. S. Bamji; A. T. Bulinski; J.-P. Crine

    1990-01-01

    The influence of oxidation on water tree degradation is examined. Studies of the thermal oxidation of cable-grade PE (polyethylene) and XLPE (cross-linked PE) and also of PE and XLPE immersed in hot aqueous solutions in the absence of an electric field are reviewed. The data are compared with the results of oxidation studies of water trees in PE and XLPE.

  9. Constructing Phylogenetic Networks from Trees

    Microsoft Academic Search

    Sergey Bereg; Kathryn Bean

    2005-01-01

    We present a new method of constructing a phylogenetic network from a given phylogenetic tree. It is based on a procedure that locally improves the tree. The procedure is quite general and can be applied to phylogenetic networks. By repeating local improvements user can introduce a given number of recombination cycles. A sequence of networks with decreasing distance deviation can

  10. Cellular Tree Classifiers Gerard Biau

    E-print Network

    Biau, Gérard

    Cellular Tree Classifiers G´erard Biau Universit´e Pierre et Marie Curie1 & Ecole Normale Sup The cellular tree classifier model addresses a fundamental problem in the design of classifiers for a parallel a consistent classifier as no cell knows the "original data size", n. However, we show that this is not so

  11. Looking/Learning Drawing: Trees.

    ERIC Educational Resources Information Center

    Hurwitz, Al; Blume, Sharon

    1985-01-01

    Secondary students are asked to study and compare three reproductions--Van Gogh's "Grove of Cypresses," Da Vinci's "Study of a Tree," and Mondrian's "Tree II." The activity will help students develop their powers of observation and analysis, powers that can be applied to their own drawings. (RM)

  12. Hazard Tree Management for Camps.

    ERIC Educational Resources Information Center

    Kong, Earl

    2002-01-01

    The principles behind a camp's hazard tree program are, first, identifying and removing those hazards that offer a clear, immediate threat, and then creating a management plan for the other trees. The plan should be written and contain goals and objectives, field evaluations, and treatments. Follow-up evaluations should be done annually and after…

  13. Trees and Dags An Introduction

    E-print Network

    Andrews, Peter B.

    is (the root of) a tree representing the S-expression " -- by structural induction on : tree a (i) iff emp(i) then {isatom() emp i = } {isatom() ((emp i = ) (emp i = ))} j := i {isatom() ((emp i = ) (emp j representation (and are therefore the same S-expression). But we have dropped emp from the base case, so that dag

  14. In Search of Moon Trees

    NSDL National Science Digital Library

    Phillips, Tony.

    2002-01-01

    In 1971, hundreds of tree seedlings germinated aboard NASA's Apollo 14 mission to the moon. A few years later, they were planted around the nation, often with much fanfare. However, no one kept a systematic record of these plantings, and as a result, the whereabouts of most of the trees remains a mystery. Visitors can read or listen to an account of the history and current status of them at this Web site, and follow links to access additional information relating to the story or to learn the location of known Moon trees. NASA scientist Dave Williams continues to search for the remaining trees and encourages readers to contact him if they believe they know of trees not currently mentioned on his list. What this site lacks in colorful, interactive features is more than made up for by its engaging feature story.

  15. How Monkeys Use Energy to Leap from Tree to Tree

    NSDL National Science Digital Library

    David E Watson

    The representation is a diagram with accompanying text, showing conversions as energy goes from the sun (electromagnetic) to the tree (chemical) to the monkey; describes how the monkey converts chemical energy into motion and heat.

  16. Can These Trees Be Saved? 

    E-print Network

    Taylor, Eric; Foster, C. Darwin

    2005-10-19

    ER-039 5-06 Can These Trees Be Saved? Eric L. Taylor, Extension Specialist, and C. Darwin Foster, Associate Department Head and Extension Program Leader for Forestry, The Texas A&M University System A storm or other disaster can leave trees... it over. Remember that time is on your side. After careful pruning of broken branches, give the tree some time to recover. A final decision can be made later. Produced by AgriLife Communications and Marketing, The Texas A&M System Extension publications...

  17. Tree Search and Quantum Computation

    E-print Network

    Luís Tarrataca; Andreas Wichert

    2015-02-06

    Traditional tree search algorithms supply a blueprint for modeling problem solving behaviour. A diverse spectrum of problems can be formulated in terms of tree search. Quantum computation, in particular Grover's algorithm, has aroused a great deal of interest since it allows for a quadratic speedup to be obtained in search procedures. In this work we consider the impact of incorporating classical search concepts alongside Grover's algorithm into a hybrid quantum search system. Some of the crucial points examined include: (1) the reverberations of contemplating the use of non-constant branching factors; (2) determining the consequences of incorporating an heuristic perspective into a quantum tree search model.

  18. On Wavelet Tree Construction German Tischler

    E-print Network

    Lonardi, Stefano

    On Wavelet Tree Construction German Tischler Lehrstuhl f¨ur Informatik 2, Universit¨at W¨urzburg, Germany CPM 2011 On Wavelet Tree Construction (1) German Tischler #12;Table of contents Definitions General Balanced wavelet tree Huffman shaped wavelet tree Stable bit key sorting In place Using additional

  19. How To Select and Plant a Tree.

    ERIC Educational Resources Information Center

    Fazio, James R., Ed.

    1991-01-01

    This bulletin furnishes information about selecting and planting trees. The tree selection process includes being aware of the physical characteristics of bare root seedlings, containerized seedlings, balled and burlapped, or potted trees and determining the proper size and root ball proportions. The section on tree planting discusses how to: (1)…

  20. Trees, soil and water : Journey to Forever

    NSDL National Science Digital Library

    Keith Addison

    2001-01-01

    Trees, soil and water: Journey to Forever - healthcare for mountains, trees for deserts, trees for people, forest, forestry, deforestation, erosion, soil conservation, water conservation, desertification This article discusses the interdependence between trees, soil, and water from a biological and conservationist standpoint.

  1. A Tool for Displaying Syntactic Trees.

    ERIC Educational Resources Information Center

    Morgan, Jerry L.

    A computer program for drawing syntactic phrase markers as trees is described. The program was developed for use on Texas Instruments Explorer Lisp machines. The tree is drawn by recursive descent, left to right. The tree-drawing function takes two arguments: (1) an atom constituting the tree, and (2) a font specification to be used in drawing the…

  2. Integrating cyber attacks within fault trees

    Microsoft Academic Search

    Igor Nai Fovino; Marcelo Masera; Alessio De Cian

    2009-01-01

    In this paper, a new method for quantitative security risk assessment of complex systems is presented, combining fault-tree analysis, traditionally used in reliability analysis, with the recently introduced Attack-tree analysis, proposed for the study of malicious attack patterns. The combined use of fault trees and attack trees helps the analyst to effectively face the security challenges posed by the introduction

  3. Sensitivity analysis of modular dynamic fault trees

    Microsoft Academic Search

    Yong Ou; Joanne Bechta Dugan

    2000-01-01

    Dynamic fault tree analysis, as currently supported by the Galileo software package, provides an effective means for assessing the reliability of embedded computer-based systems. Dynamic fault trees extend traditional fault trees by defining special gates to capture sequential and functional dependency characteristics. A modular approach to the solution of dynamic fault trees effectively applies Binary Decision Diagram (BOD) and Markov

  4. A Novel Approach for Compressing Phylogenetic Trees

    E-print Network

    Williams, Tiffani

    A Novel Approach for Compressing Phylogenetic Trees Suzanne J. Matthews, Seung-Jin Sul, and Tiffani,sulsj,tlw}@cse.tamu.edu Abstract. Phylogenetic trees are tree structures that depict relation- ships between organisms. Popular analysis techniques often produce large collections of candidate trees, which are expensive to store. We

  5. Action trees and moral judgment Joshua Knobe

    E-print Network

    Knobe, Joshua

    1 Action trees and moral judgment Joshua Knobe Yale University [Forthcoming in Topics in Cognitive of an action tree. A question now arises about the relationship between this action tree representation of the action tree and then go on to use this representation in making moral judgments. The present paper argues

  6. Research Summary Health Benefits of Street Trees

    E-print Network

    Research Summary Health Benefits of Street Trees Street trees can have an important role. Health and well-being objectives have been elements of each country's forest strategy, and street trees This research aimed to: o Assess recent economic evidence of the health benefits provided by street trees

  7. Hardwood Tree Improvement and Regeneration Center

    E-print Network

    FNR-214-W Hardwood Tree Improvement and Regeneration Center North Central Research Station USDA of Tree Planting William L. Hoover Department of Forestry and Natural Resources, Purdue University Trees and timber production. Altruism motivates many landowners to plant trees. There are, however, those who plant

  8. TREE MAINTENANCE AND REMOVAL 31. A GENERAL

    E-print Network

    US Army Corps of Engineers

    EM 385-1-1 XX Jun 13 SECTION 31 TREE MAINTENANCE AND REMOVAL 31. A GENERAL 31.A.01 References. a, and Distribution; d. ANSI A300 ­ American National Standard for Tree Care Operations ­ Tree, Shrub, and Other Woody- Mounted Elevating and Rotating Aerial Devices. 31.A.02 Tree maintenance or removal shall be performed

  9. Tunnel of the California Tunnel Tree

    USGS Multimedia Gallery

    In this image, the tunnel through the California Tunnel Tree may be seen. The tunnel was cut through the giant sequoia tree in 1895 to allow coaches, and eventually cars, to drive through the tree as part of a marketing stunt. The California Tunnel Tree is the only living giant sequoia with a t...

  10. TIMCHAMPION 11055 Painted Tree Road

    E-print Network

    Bodner, George M.

    edited by TIMCHAMPION 11055 Painted Tree Road Charlone. NC 28226 An Alternativeto Halogenated coefficientfor the extrac- tion of iodine between CCla and water. Glasstone (3)reports values of 85.1-87.5for

  11. Summing tree graphs at threshold

    E-print Network

    Lowell S. Brown

    1992-09-01

    The solution of the classical field equation generates the sum of all tree graphs. We show that the classical equation reduces to an easily solved ordinary differential equation for certain multiparticle threshold amplitudes and compute these amplitudes.

  12. Simplicial matrix-tree theorems

    E-print Network

    Duval, Art M; Martin, Jeremy L

    2008-01-01

    We generalize the definition and enumeration of spanning trees from the setting of graphs to that of arbitrary-dimensional simplicial complexes $\\Delta$, extending an idea due to G. Kalai. We prove a simplicial version of the Matrix-Tree Theorem that counts simplicial spanning trees, weighted by the squares of the orders of their top-dimensional integral homology groups, in terms of the Laplacian matrix of $\\Delta$. As in the graphic case, one can obtain a more finely weighted generating function for simplicial spanning trees by assigning an indeterminate to each vertex of $\\Delta$ and replacing the entries of the Laplacian with Laurent monomials. When $\\Delta$ is a shifted complex, we give a combinatorial interpretation of the eigenvalues of its weighted Laplacian and prove that they determine its set of faces uniquely, generalizing known results about threshold graphs and unweighted Laplacian eigenvalues of shifted complexes.

  13. If a Tree Falls in the Forest ...

    NSDL National Science Digital Library

    This activity has students explore the role that forests play in their own lives by listing everyday products made from trees. They use the Internet to find as many uses for trees as possible in order to develop a class list that should include foods from trees, products derived from all parts of a tree, environmental benefits of trees, and recreational uses of trees. Students are then asked to imagine a day in their lives without trees and consider how their routine would differ and how their environment would change. This site also contains ideas for assessment and ways of extending the lesson.

  14. Centennial Celebration of the Gift of Trees to Columbus, OH Cherry Tree Planting Ceremony

    E-print Network

    Jones, Michelle

    Centennial Celebration of the Gift of Trees to Columbus, OH Cherry Tree Planting Ceremony Friday in Detroit Planting of the Cherry Blossom Trees Sakura ­ sung by Fort Hayes Arts & Academic High for students · The trees were provided by American Forests. · Pictures of Cherry Trees were provided

  15. Improvements to a Class of Distance Matrix Methods for Inferring Species Trees from Gene Trees

    E-print Network

    Rosenberg, Noah

    Improvements to a Class of Distance Matrix Methods for Inferring Species Trees from Gene Trees available for inferring species trees from gene trees, the GLASS method of Mossel and Roch (2010 branch length estimates. Further, GLASS and STEAC have been shown to be consistent estimators of tree

  16. Revised slightly from Arborist News 14 (2) 24-26, 2005. Tree Biology and Problem Trees

    E-print Network

    Revised slightly from Arborist News 14 (2) 24-26, 2005. Tree Biology and Problem Trees By Kevin T. Smith, USDA Forest Service, Durham, NH 03824 USA Modern Arboriculture and Problem Trees: Have you met any problem trees? Have you created any problem trees? Can you spot them early or even prevent them

  17. A SIMPLE BIJECTION BETWEEN A SUBCLASS OF 2-BINARY TREES AND TERNARY TREES

    E-print Network

    Wagner, Stephan

    NOTE A SIMPLE BIJECTION BETWEEN A SUBCLASS OF 2-BINARY TREES AND TERNARY TREES HELMUT PRODINGER We consider the subclass of 2-binary trees, where · nodes are labelled black or white, · the root is labelled] that these trees are in bijection with ternary trees (and henceforth enumerated by 1 2n+1 3n n ). In this note we

  18. High-Dimensional Structure Learning of Graphical Models: Trees, Latent Trees & Beyond

    E-print Network

    Anandkumar, Animashree

    High-Dimensional Structure Learning of Graphical Models: Trees, Latent Trees & Beyond Anima Tan, and Alan Willsky. UIUC Seminar Anima Anandkumar (UCI) Trees, Latent Trees & Beyond 11/08/2010 1 / 52 #12;Graphical Models: Motivation Example: Contextual Object Recognition SKY ROAD AREA TREE CAR CAR

  19. ATV: display and manipulation of annotated phylogenetic trees ATV: display and manipulation of annotated phylogenetic trees

    E-print Network

    Eddy, Sean

    ATV: display and manipulation of annotated phylogenetic trees 8/10/01 1 ATV: display and manipulation of annotated phylogenetic trees Christian M. Zmasek and Sean R. Eddy Howard Hughes Medical: {zmasek,eddy}@genetics.wustl.edu Key words: tree display, tree viewer, phylogenetic tree, java

  20. 36 CFR 223.4 - Exchange of trees or portions of trees.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Exchange of trees or portions of trees. 223.4 Section 223.4 Parks, Forests...PRODUCTS General Provisions § 223.4 Exchange of trees or portions of trees. Trees or portions of...

  1. reference to a tree with full foliage under local conditions (the `local tree' method). Usually this

    E-print Network

    reference to a tree with full foliage under local conditions (the `local tree' method). Usually this method involves selecting the tree with the greatest amount of foliage in the general vicinity of a survey plot to serve as a standard against which the plot trees are assessed. The same local tree

  2. 36 CFR 223.4 - Exchange of trees or portions of trees.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Exchange of trees or portions of trees. 223.4 Section 223.4 Parks, Forests...PRODUCTS General Provisions § 223.4 Exchange of trees or portions of trees. Trees or portions of...

  3. 36 CFR 223.4 - Exchange of trees or portions of trees.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Exchange of trees or portions of trees. 223.4 Section 223.4 Parks, Forests...PRODUCTS General Provisions § 223.4 Exchange of trees or portions of trees. Trees or portions of...

  4. Quantum Simulation of Phylogenetic Trees

    E-print Network

    Demosthenes Ellinas; Peter Jarvis

    2011-05-09

    Quantum simulations constructing probability tensors of biological multi-taxa in phylogenetic trees are proposed, in terms of positive trace preserving maps, describing evolving systems of quantum walks with multiple walkers. Basic phylogenetic models applying on trees of various topologies are simulated following appropriate decoherent quantum circuits. Quantum simulations of statistical inference for aligned sequences of biological characters are provided in terms of a quantum pruning map operating on likelihood operator observables, utilizing state-observable duality and measurement theory.

  5. Generic physical protection logic trees

    SciTech Connect

    Paulus, W.K.

    1981-10-01

    Generic physical protection logic trees, designed for application to nuclear facilities and materials, are presented together with a method of qualitative evaluation of the trees for design and analysis of physical protection systems. One or more defense zones are defined where adversaries interact with the physical protection system. Logic trees that are needed to describe the possible scenarios within a defense zone are selected. Elements of a postulated or existing physical protection system are tagged to the primary events of the logic tree. The likelihood of adversary success in overcoming these elements is evaluated on a binary, yes/no basis. The effect of these evaluations is propagated through the logic of each tree to determine whether the adversary is likely to accomplish the end event of the tree. The physical protection system must be highly likely to overcome the adversary before he accomplishes his objective. The evaluation must be conducted for all significant states of the site. Deficiencies uncovered become inputs to redesign and further analysis, closing the loop on the design/analysis cycle.

  6. Self-adjusting binary search trees

    Microsoft Academic Search

    Daniel Dominic Sleator; Robert Endre Tarjan

    1985-01-01

    The splay tree, a self-adjusting form of binary search tree, is developed and analyzed. The binary search tree is a data structure for representing tables and lists so that accessing, inserting, and deleting items is easy. On an n-node splay tree, all the standard search tree operations have an amortized time bound of O(log n) per operation, where by “amortized

  7. Microwave sensing of tree trunks

    NASA Astrophysics Data System (ADS)

    Jezova, Jana; Mertens, Laurence; Lambot, Sebastien

    2015-04-01

    The main subject of this research is the observation of the inner part of living tree trunks using ground-penetrating radar (GPR). Trees are everyday part of human life and therefore it is important to pay attention to the tree conditions. The most obvious consequence of the poor tree condition is dead or injury caused by falling tree. The trunk internal structure is divided into three main parts: heartwood, sapwood and bark, which make this medium highly anisotropic and heterogeneous. Furthermore, the properties of the wood are not only specie-dependent but also depend on genetic and on environmental conditions. In urban areas the main problem for the stability of the trees relies in the apparition of decays provoked by fungi, insect or birds. This results in cavities or decreasing of the support capacity of the tree. GPR has proved itself to be a very powerful electromagnetic tool for non-destructive detection of buried objects. Since the beginning of the 20th century it has been used in several different areas (archaeology, landmine detection, civil engineering, ...). GPR uses the principle of the scattering of the electromagnetic waves that are radiated from a transmitting antenna. Then the waves propagate through the medium and are reflected from the object and then they are received by a receiving antenna. The velocity of the scattered signal is determined primarily by the permittivity of the material. The optimal functionality of the GPR was investigated using the numerical simulation tool gprMax2D. This tool is based on a Finite-Difference Time-Domain (FDTD) numerical model. Subsequently, the GPR functionality was tested using the laboratory model of a decayed tree trunk. Afterwards, the results and lessons learnt in the simplified tests will be used in the processing of the real data and will help to achieve deeper understanding of them. The laboratory model of the tree trunk was made by plastic or carton pipes and filled by sand. Space inside the model was divided into three sections to separate parts with different moisture (heartwood and sapwood) or empty space (decays). For easier manipulation with the antenna we developed a special ruler for measuring the distance along the scans. Instead of the surveying wheel we read the distance with a camera, which was fixed on the antenna and focused on the ruler with a binary pattern. Hence, during whole measurement and the data processing we were able to identify an accurate position on the tree in view of the scan. Some preliminary measurements on the trees were also conducted. They were performed using a GSSI 900 MHz antenna. Several tree species (beech, horse-chestnut, birch, ...) in Louvain-la-Neuve and Brussels, Belgium, have been investigated to see the internal structure of the tree decays. The measurements were carried out mainly by circumferential measurement around the trunk and also by vertical measurement along the trunk for approximate detection of the cavity. The comparison between the numerical simulations, simplified tree trunk model and real data from trees is presented. This research is funded by the Fonds de la Recherche Scientifique (FNRS, Belgium) and benefits from networking activities carried out within the EU COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar".

  8. A Model In Which There Are Jech Kunen Trees But There Are No Kurepa Trees 1

    E-print Network

    Jin, Renling

    A Model In Which There Are Jech Kunen Trees But There Are No Kurepa Trees 1 Saharon Shelah2 and Renling Jin Abstract By an !1 tree we mean a tree of power !1 and height !1. We call an !1 tree a Jech Kunen tree if it has many branches for some strictly between !1 and 2!1 . In this paper we construct

  9. DataTree and UniTree: software for file and storage management

    Microsoft Academic Search

    F. McClain

    1990-01-01

    The capabilities and advantages of DataTree and UniTree (hierarchical file- and storage-management systems for networked, multivendor computing environments) are discussed. DataTree is an advanced centralized MVS-based system; UniTree is a Unix-based file-server product. DataTree is the commercial version of the common file system (CFS) developed at the Los Alamos National Laboratory. The DataTree server platform is built upon the MVS

  10. Red-black Trees To know what a red-black tree is (10.1).

    E-print Network

    Liang, Y. Daniel

    809 CHAPTER 10 Red-black Trees Objectives · To know what a red-black tree is (§10.1). · To convert a red-black tree to a 2-4 tree and vice versa (§10.2). · To design the RBTree class that extends the BinaryTree class (§10.3). · To insert an element in a red-black tree and resolve the double red problem

  11. Decision Tree Induction Based on Efficient Tree Restructuring 1 Paul E. Utgoff utgoff@cs.umass.edu

    E-print Network

    Massachusetts at Amherst, University of

    Decision Tree Induction Based on Efficient Tree Restructuring 1 Paul E. Utgoff utgoff to restructure a decision tree efficiently enables a variety of ap­ proaches to decision tree induction incremental tree induction (ITI), and the other being non­incremental tree induction using a measure of tree

  12. Decision Tree Induction Based on Efficient Tree Restructuring1 Paul E. Utgoff utgoff@cs.umass.edu

    E-print Network

    Massachusetts at Amherst, University of

    Decision Tree Induction Based on Efficient Tree Restructuring1 Paul E. Utgoff utgoff to restructure a decision tree efficiently enables a variety of ap- proaches to decision tree induction incremental tree induction (ITI), and the other being non-incremental tree induction using a measure of tree

  13. Genealogical trees from genetic distances

    NASA Astrophysics Data System (ADS)

    Prignano, L.; Serva, M.

    2009-06-01

    In a population with haploid reproduction any individual has a single parent in the previous generation. If all genealogical distances among pairs of individuals (generations from the closest common ancestor) are known it is possible to exactly reconstruct their genealogical tree. Unfortunately, in most cases, genealogical distances are unknown and only genetic distances are available. The genetic distance between two individuals is measurable from differences in mtDNA (mitochondrial DNA) since in the case of humans or other complex organisms mtDNA is transmitted in a haploid manner. An analogous distance can be also computed for languages where it may be measured from lexical differences, in this case, nevertheless, haploid reproduction is only a raw approximation. Assuming a constant rate of mutation, these genetic distances are random and proportional only on average to genealogical ones. The reconstruction of the genealogical tree from the available genetic distances is forceful imprecise. In this paper we try to quantify the error one may commit in the reconstruction of the tree for different degrees of randomness. The errors may concern both topology of the tree (the branching hierarchy) and, in case of correct topology, the proportions of the tree (length of various branches).

  14. Superstable groups acting on trees

    E-print Network

    Houcine, Abderezak Ould

    2008-01-01

    We study superstable groups acting on trees. We prove that an action of an $\\omega$-stable group on a simplicial tree is trivial. This shows that an HNN-extension or a nontrivial free product with amalgamation is not $\\omega$-stable. It is also shown that if $G$ is a superstable group acting nontrivially on a $\\Lambda$-tree, where $\\Lambda=\\mathbb Z$ or $\\Lambda=\\mathbb R$, and if $G$ is either $\\alpha$-connected and $\\Lambda=\\mathbb Z$, or if the action is irreducible, then $G$ interprets a simple group having a nontrivial action on a $\\Lambda$-tree. In particular if $G$ is superstable and splits as $G=G_1*_AG_2$, with the index of $A$ in $G_1$ different from 2, then $G$ interprets a simple superstable non $\\omega$-stable group. We will deal with "minimal" superstable groups of finite Lascar rank acting nontrivially on $\\Lambda$-trees, where $\\Lambda=\\mathbb Z$ or $\\Lambda=\\mathbb R$. We show that such groups $G$ have definable subgroups $H_1 \\lhd H_2 \\lhd G$, $H_2$ is of finite index in $G$, such that if $H...

  15. The most parsimonious tree for random data.

    PubMed

    Fischer, Mareike; Galla, Michelle; Herbst, Lina; Steel, Mike

    2014-11-01

    Applying a method to reconstruct a phylogenetic tree from random data provides a way to detect whether that method has an inherent bias towards certain tree 'shapes'. For maximum parsimony, applied to a sequence of random 2-state data, each possible binary phylogenetic tree has exactly the same distribution for its parsimony score. Despite this pleasing and slightly surprising symmetry, some binary phylogenetic trees are more likely than others to be a most parsimonious (MP) tree for a sequence of k such characters, as we show. For k=2, and unrooted binary trees on six taxa, any tree with a caterpillar shape has a higher chance of being an MP tree than any tree with a symmetric shape. On the other hand, if we take any two binary trees, on any number of taxa, we prove that this bias between the two trees vanishes as the number of characters k grows. However, again there is a twist: MP trees on six taxa for k=2 random binary characters are more likely to have certain shapes than a uniform distribution on binary phylogenetic trees predicts. Moreover, this shape bias appears, from simulations, to be more pronounced for larger values of k. PMID:25079136

  16. Interpreting the universal phylogenetic tree.

    PubMed

    Woese, C R

    2000-07-18

    The universal phylogenetic tree not only spans all extant life, but its root and earliest branchings represent stages in the evolutionary process before modern cell types had come into being. The evolution of the cell is an interplay between vertically derived and horizontally acquired variation. Primitive cellular entities were necessarily simpler and more modular in design than are modern cells. Consequently, horizontal gene transfer early on was pervasive, dominating the evolutionary dynamic. The root of the universal phylogenetic tree represents the first stage in cellular evolution when the evolving cell became sufficiently integrated and stable to the erosive effects of horizontal gene transfer that true organismal lineages could exist. PMID:10900003

  17. Parking on a Random Tree

    E-print Network

    H. Dehling; S. R. Fleurke; C. Kuelske

    2007-11-26

    Consider an infinite tree with random degrees, i.i.d. over the sites, with a prescribed probability distribution with generating function G(s). We consider the following variation of Renyi's parking problem, alternatively called blocking RSA: at every vertex of the tree a particle (or car) arrives with rate one. The particle sticks to the vertex whenever the vertex and all of its nearest neighbors are not occupied yet. We provide an explicit expression for the so-called parking constant in terms of the generating function.

  18. Water Transport in Trees--An Artificial Laboratory Tree

    ERIC Educational Resources Information Center

    Susman, K.; Razpet, N.; Cepic, M.

    2011-01-01

    Water transport in tall trees is an everyday phenomenon, seldom noticed and not completely understood even by scientists. As a topic of current research in plant physiology it has several advantages for presentation within school physics lectures: it is interdisciplinary and clearly shows the connection between physics and biology; the…

  19. Tree rings and rockfall -Anatomic tree reactions and

    E-print Network

    Stoffel, Markus

    dem depArtement für GeowissenschAften - GeoGrAphie universität freiburG (schweiz) Tree rings Universität Freiburg in der Schweiz vorgelegt von Dominique Manuel SCHNEUWLY aus Liebistorf FR (Schweiz - Naturwissenschaftlichen Fakultät der Universität Freiburg, Schweiz, im August 2009 aufgrund der Gutachten von Prof. Michel

  20. Profiles of random trees: Plane-oriented recursive trees

    Microsoft Academic Search

    Hsien-kuei Hwang

    2007-01-01

    We derive several limit results for the profile of random plan e-oriented recursive trees. These include the limit distribution of the normalized profi le, asymptotic bimodality of the variance, asymptotic approximation to the expected width and the correlation coefficients of two level sizes. Most of our proofs are based on a method of moments. We also discover an unexpected connection

  1. AncesTrees: ancestry estimation with randomized decision trees.

    PubMed

    Navega, David; Coelho, Catarina; Vicente, Ricardo; Ferreira, Maria Teresa; Wasterlain, Sofia; Cunha, Eugénia

    2014-07-23

    In forensic anthropology, ancestry estimation is essential in establishing the individual biological profile. The aim of this study is to present a new program-AncesTrees-developed for assessing ancestry based on metric analysis. AncesTrees relies on a machine learning ensemble algorithm, random forest, to classify the human skull. In the ensemble learning paradigm, several models are generated and co-jointly used to arrive at the final decision. The random forest algorithm creates ensembles of decision trees classifiers, a non-linear and non-parametric classification technique. The database used in AncesTrees is composed by 23 craniometric variables from 1,734 individuals, representative of six major ancestral groups and selected from the Howells' craniometric series. The program was tested in 128 adult crania from the following collections: the African slaves' skeletal collection of Valle da Gafaria; the Medical School Skull Collection and the Identified Skeletal Collection of 21st Century, both curated at the University of Coimbra. The first step of the test analysis was to perform ancestry estimation including all the ancestral groups of the database. The second stage of our test analysis was to conduct ancestry estimation including only the European and the African ancestral groups. In the first test analysis, 75 % of the individuals of African ancestry and 79.2 % of the individuals of European ancestry were correctly identified. The model involving only African and European ancestral groups had a better performance: 93.8 % of all individuals were correctly classified. The obtained results show that AncesTrees can be a valuable tool in forensic anthropology. PMID:25053239

  2. The Shapley value of phylogenetic trees.

    PubMed

    Haake, Claus-Jochen; Kashiwada, Akemi; Su, Francis Edward

    2008-04-01

    Every weighted tree corresponds naturally to a cooperative game that we call a tree game; it assigns to each subset of leaves the sum of the weights of the minimal subtree spanned by those leaves. In the context of phylogenetic trees, the leaves are species and this assignment captures the diversity present in the coalition of species considered. We consider the Shapley value of tree games and suggest a biological interpretation. We determine the linear transformation M that shows the dependence of the Shapley value on the edge weights of the tree, and we also compute a null space basis of M. Both depend on the split counts of the tree. Finally, we characterize the Shapley value on tree games by four axioms, a counterpart to Shapley's original theorem on the larger class of cooperative games. We also include a brief discussion of the core of tree games. PMID:17805545

  3. DATA TRANSFORMATION FOR DECISION TREE ENSEMBLES

    E-print Network

    Brown, Gavin

    of Random Linear Oracle Framework and Its Extensions 67 4.1 Diverse Linear Multivariate Decision Trees . . . . . . . . . . . . . . . . . . . . . . . . 51 2.7.7 Extremely Randomized Trees . . . . . . . . . . . . . . . . . 52 2.7.8 The Random Oracle Framework . . . . . . . . . . . . . . . . 52 2.8 Conclusion

  4. Wavelet tree quantization for copyright protection watermarking

    Microsoft Academic Search

    Shih-hao Wang; Yuan-pei Lin

    2004-01-01

    This paper proposes a wavelet-tree-based blind watermarking scheme for copyright protection. The wavelet coefficients of the host image are grouped into so-called super trees. The watermark is embedded by quantizing super trees. The trees are so quantized that they exhibit a large enough statistical difference, which will later be used for watermark extraction. Each watermark bit is embedded in perceptually

  5. RELT - Visualizing Trees on Mobile Devices

    Microsoft Academic Search

    Jie Hao; Kang Zhang; Mao Lin Huang

    2007-01-01

    The small screens on increasingly used mobile devices challenge the traditional visualization methods designed for desktops.\\u000a This paper presents a method called “Radial Edgeless Tree” (RELT) for visualizing trees in a 2-dimensional space. It combines\\u000a the existing connection tree drawing with the space-filling approach to achieve the efficient display of trees in a small\\u000a geometrical area, such as the screen

  6. Diversity of Endophytic Bacteria in Forest Trees

    Microsoft Academic Search

    Hironari Izumi

    \\u000a A group of studies on the diversity of endophytic bacteria in forest trees is presented in terms of host plant species variety\\u000a and the number of reports. Many host tree species are underrepresented in these studies: Trees in the tropics as well as some\\u000a important temperate tree species, such as those belonging to the genera of Alnus and Fagus, have

  7. Exploring Syntactic Structural Features for Sub-Tree Alignment using Bilingual Tree Kernels

    E-print Network

    Tan, Chew Lim

    Exploring Syntactic Structural Features for Sub-Tree Alignment using Bilingual Tree Kernels Jun Sun translational equivalences and apply BTKs to sub-tree alignment along with some plain features. Our study reveals that the struc- tural features embedded in a bilingual parse tree pair are very effective for sub

  8. Effect of tree channel conductivity on electrical tree shape and breakdown in XLPE cable insulation samples

    Microsoft Academic Search

    Xiangrong Chen; Yang Xu; Xiaolong Cao; S. J. Dodd; L. A. Dissado

    2011-01-01

    The results of an investigation into electrical tree growth in XLPE cable insulation using an embedded needle electrode are reported for a range of voltages from 9 kV rms to 27 kV rms. The partial discharge (PD) activity and tree structures were measured simultaneously throughout the tree growth and the trees were recorded from initiation up to and including the

  9. The probability distribution of ranked gene trees on a species tree James H. Degnan a,

    E-print Network

    Rosenberg, Noah

    The probability distribution of ranked gene trees on a species tree James H. Degnan a, , Noah A and the sequence of coalescences for a random gene tree are considered. We derive the probability distribution reserved. 1. Introduction Recent studies have investigated the probability distribution of random gene tree

  10. RELATING TREE PHYSIOLOGY TO PAST AND FUTURE CHANGES IN TROPICAL RAINFOREST TREE COMMUNITIES

    E-print Network

    Coley, Phyllis

    RELATING TREE PHYSIOLOGY TO PAST AND FUTURE CHANGES IN TROPICAL RAINFOREST TREE COMMUNITIES THOMAS. Predicting future changes in tropical rainforest tree communities requires a good under- standing of past to which tropical rainforest tree communities have changed during the last few thousand years has been

  11. DOES TREE HARDNESS INFLUENCE NEST-TREE SELECTION BY PRIMARY CAVITY NESTERS?

    Microsoft Academic Search

    JAKE SCHEPPS; STEVE LOHR; THOMAS E. MARTIN

    may vary among bird species, causing nest-tree selection to vary among excavator species. We examined use of quaking aspens (Populus tremuloides) for nest trees as a function of tree hardness in four species of woodpeckers: Williamson's Sapsucker (Sphyrapicus thyroideus), Red-naped Sapsucker (S. nuchalis), Downy Woodpecker (Picoides pubescens), and Hairy Woodpecker (P. villosus). Hardness of trees was measured at 95 nest

  12. TREE2TREE: NEURON SEGMENTATION FOR GENERATION OF NEURONAL Saurav Basu1

    E-print Network

    Acton, Scott

    datasets. Current automatic state of the art algorithms for neuron tracing fail to work in neuron images Tree2Tree, a robust automatic neuron segmentation and morphology generation algorithm. It uses a localTREE2TREE: NEURON SEGMENTATION FOR GENERATION OF NEURONAL MORPHOLOGY Saurav Basu1 , Alla Aksel1

  13. Plastic Trees: Interactive Self-Adapting Botanical Tree Models Sren Pirk1

    E-print Network

    Deussen, Oliver

    ). The same tree species that has a well-developed crown when grown in an open space might have a longer trunk and only a small tree crown when standing in a forest. The variety of plant shapes can be capturedPlastic Trees: Interactive Self-Adapting Botanical Tree Models Sören Pirk1 Ondrej Stava2 Julian

  14. Combining dynamic fault trees and event trees for probabilistic risk assessment

    Microsoft Academic Search

    Hong Xu; Joanne Bechta Dugan

    2004-01-01

    As system analysis methodologies, both event tree analysis (ETA) and fault tree analysis (FTA) are used in probabilistic risk assessment (PRA), especially in identifying system interrelationships due to shared events. Although there are differences between them, ETA and FTA, are so closely linked that fault trees (FT) are often used to quantify system events that are part of event tree

  15. Totally Tree-mendous Activities: Projects To Discover the Beauty and Benefits of Trees.

    ERIC Educational Resources Information Center

    Hollister, Sarah

    This teacher's guide supplies information and hands-on activities to teach about trees from several disciplines. Activities are grouped into six areas that cover botany, social studies, arts and literature (aesthetics), and trees as a resource. Sections include: (1) Tree Identification, which defines trees and leaves and presents activities that…

  16. Box-Trees and R-trees with Near-Optimal Query Time Pankaj K. Agarwaly

    E-print Network

    Agarwal, Pankaj K.

    Box-Trees and R-trees with Near-Optimal Query Time Pankaj K. Agarwaly Mark de Bergz Joachim Gudmundssonx Mikael Hammarx Herman J. Haverkortz Abstract A box-tree is a bounding-box hierarchy that uses axis-aligned boxes as bounding volumes. The stab- bing number of a box-tree with respect to a given type of query

  17. Monitoring amenity tree health in England The Condition Survey of Non-woodland Amenity Trees

    E-print Network

    36 Monitoring amenity tree health in England The Condition Survey of Non-woodland Amenity Trees)-led survey which enables us to monitor the condition of amenity trees in parks, city streets and stately countries since 1987 (Hendry, 2005). Whilst the Forest Condition Survey concentrates on forest trees

  18. A Characterization of the Set of Species Trees that Produce Anomalous Ranked Gene Trees

    E-print Network

    Rosenberg, Noah

    A Characterization of the Set of Species Trees that Produce Anomalous Ranked Gene Trees James H. Degnan, Noah A. Rosenberg, and Tanja Stadler Abstract--Ranked gene trees, which consider both the gene tree topology and the sequence in which gene lineages separate, can potentially provide a new source

  19. Inferring Species Trees Directly from Biallelic Genetic Markers: Bypassing Gene Trees in a Full Coalescent Analysis

    E-print Network

    Rosenberg, Noah

    Inferring Species Trees Directly from Biallelic Genetic Markers: Bypassing Gene Trees in a Full framework for estimating species trees and species demograph- ics from genetic markers. However, practical trees possible for each genetic marker. Here we describe a polynomial-time algorithm that computes

  20. trees.sty: A Macro for Drawing Binary or Ternary Trees

    E-print Network

    Mintmire, John W.

    trees.sty: A Macro for Drawing Binary or Ternary Trees april 1990 The following macros let you draw a (binary or ternary) tree of any size. For each will give you some ideas on designi* *ng similar things for, e.g., digital circuits. Trees

  1. Optimizing tree and character compatibility across several phylogenetic trees Simone Linza,b

    E-print Network

    St. John, Katherine

    Optimizing tree and character compatibility across several phylogenetic trees Simone Linza, Bronx, NY, United States. Abstract Given a set R of rooted phylogenetic trees on overlapping taxa, it takes polynomial time to decide whether or not there exists a rooted phylogenetic tree

  2. TreeDT: Tree Pattern Mining for Gene Mapping Petteri Sevon, Hannu Toivonen, and Vesa Ollikainen

    E-print Network

    Toivonen, Hannu

    TreeDT: Tree Pattern Mining for Gene Mapping Petteri Sevon, Hannu Toivonen, and Vesa Ollikainen Abstract--We describe TreeDT, a novel association-based gene mapping method. Given a set of disease-associated haplotypes and a set of control haplotypes, TreeDT predicts likely locations of a disease susceptibility gene

  3. A TREE OBSCURED BY VINES: HORIZONTAL GENE TRANSFER AND THE MEDIAN TREE

    E-print Network

    Kim, Junhyong

    1 A TREE OBSCURED BY VINES: HORIZONTAL GENE TRANSFER AND THE MEDIAN TREE METHOD OF ESTIMATING University New Haven, CT 06520, USA junhyong.kim@yale.edu, ben@aya.yale.edu A phylogeny is a tree graph the phylogeny of whole organisms (species trees) using bio-molecular sequences. When multiple sequences

  4. Street tree valuation systems The Capital Asset Value for Amenity Trees (CAVAT) scheme provides a method

    E-print Network

    Street tree valuation systems The Capital Asset Value for Amenity Trees (CAVAT) scheme provides a method for managing trees as public assets in London. A literature and methodological review was commissioned to assess approaches to estimating the amenity value of street trees to feed into Forestry

  5. Trees of Our National Forests.

    ERIC Educational Resources Information Center

    Forest Service (USDA), Washington, DC.

    Presented is a description of the creation of the National Forests system, how trees grow, managing the National Forests, types of management systems, and managing for multiple use, including wildlife, water, recreation and other uses. Included are: (1) photographs; (2) line drawings of typical leaves, cones, flowers, and seeds; and (3)…

  6. TREE FAILURES AND ACCIDENTS IN

    E-print Network

    Standiford, Richard B.

    , and other categories of information. Use of this system allows site managers to control hazard at lower cost. A data management system has been developed for storage and retrieval of tree failure and hazard data reduction; recreation areas; safety standards; data management; computer programs. #12;INTRODUCTION

  7. The Gift of the Tree

    NSDL National Science Digital Library

    Marla Wagner Jones

    2009-09-01

    A piece of children's literature can be a powerful tool for teaching and learning science; however, it takes more than reading about a topic to qualify as "doing science." Inspired by the book, The Gift of the Tree , the author developed an in-dep

  8. Feathered Hollow in Living Tree

    USGS Multimedia Gallery

    Hollow in living tree in gallery forest of tributary to Tebicuary river. Grey feathers stuck along bottom of entrance suggest that it may be used by a bird. Paraguay is home to at least 589 breeding bird species and 120 migratory bird species. The Ñeembucú Region is typified by extensi...

  9. Throughfall Variation under Tree Crowns

    Microsoft Academic Search

    Benjamin B. Stout; Richard J. McMahon

    1961-01-01

    It is suggested that the experimental design for sample measurement of through- fall may be improved. Specifically, distance and direction from trunk may constitute a signifi- cant source of variation that could be separated in analysis of variance from the unexplained variation. Throughfall was measured at three positions and four directions under the crowns of four trees during the summer

  10. MORINGACEAE Martinov Drumstick Tree Family

    E-print Network

    Olson, Mark

    ); ovules anatropous; style 1 (hollow, with a gaping stigmatic aperture). Fruits capsular, valvate, laxly ducts are present in the pith and also on trauma in the bark, and exudes a straw- or pinkish-colored gum, alluding to young fruit] Trees or shrubs, [massive pachycauls, baobab-like with water-storing trunk

  11. Dating the Tree of Life

    Microsoft Academic Search

    Michael J. Benton; Francisco J. Ayala

    2003-01-01

    The relative merits of molecular and paleontological dates of major branching points in the tree of life are currently debated. In some cases, molecular date estimates are up to twice as old as paleontological dates. However, although it is true that paleontological dates are often too young (missing fossils), molecular dates are often too old (statistical bias). Intense study of

  12. MYCOTOXINS IN EDIBLE TREE NUTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tree nuts (almonds, pistachios, and walnuts) are an exceptionally valuable crop, especially in California, with an aggregate value approaching $3.5 billion. Much of this economic value comes from overseas markets, with up to 60% of the crop being exported. The product can be contaminated with aflat...

  13. Chopping Down the Cherry Tree.

    ERIC Educational Resources Information Center

    Griswold, Jerry

    1995-01-01

    Attempts once again to put to rest the infamous "I cannot tell a lie" episode involving George Washington and a downed cherry tree. Appends an editor's note that states that William Bennett's "The Children's Book of Virtues" which perpetuates this infamous piece of "fakelore." (RS)

  14. Cedar Tree in Bryce Canyon

    USGS Multimedia Gallery

    A cedar tree in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandstone that forms their ba...

  15. Selecting Landscape Plants: Shade Trees

    E-print Network

    Liskiewicz, Maciej

    for any landscape plan. They set the stage for the entire home grounds design. The type usedSelecting Landscape Plants: Shade Trees Diane Relf, Extension Specialist, Horticulture, Virginia. Many will live and enhance the landscape for 100 or more years if they are given a chance. Because

  16. The Ordered Core Based Tree Protocol

    Microsoft Academic Search

    Clay Shields; J. J. Garcia-luna-aceves

    1997-01-01

    This paper presents a new protocol, the Ordered Core Based Tree(OCBT) protocol, which remedies several shortcomings of the CoreBased Tree (CBT) multicast protocol. We show that the CBT protocolcan form loops during periods of routing instability, and that itcan consistently fail to build a connected multicast tree, even whenthe underlying routing is stable. The OCBT protocol provably eliminatesthese deficiencies and

  17. Case Study: Visualizing Sets of Evolutionary Trees

    E-print Network

    Amenta, Nina

    , "Which strain of anthrax is this?". More fundamentally, evolutionary trees provide a framework in which relationships of the taxa. If, on the other hand, the set of trees contains subsets which differ consid- erably from each other, the consensus tree of the whole set will contain very few internal nodes, all of high

  18. Persistent search trees and maxima finding

    E-print Network

    Collins, Carol Esther

    1987-01-01

    . Ordinarily, a search tree changes over time as elements are inserted and deleted. Such a tree is said to be ephemera/since making a change destroys the old structure and replaces it with a new one. A persistent or partially persistent search tree is one...

  19. Cache-oblivious dynamic search trees

    E-print Network

    Kasheff, Zardosht, 1981-

    2004-01-01

    I have implemented a cache-oblivious dynamic search tree as an alternative to the ubiquitious B-tree. I use a binary tree with a "van Endcle Boas" layout whose leaves point to intervals in a "packed memory structure". We ...

  20. Self-organized criticality in electrical treeing

    Microsoft Academic Search

    M. D. Noskov; A. S. Malinovski; M. Sack; A. J. Schwab

    2001-01-01

    Self-organized criticality aspects of electrical treeing in solid dielectric under ac voltage are considered. The sandpile model of self-organized criticality is modified to describe partial discharge activity from electrical treeing. A comparison of avalanche statistics simulated by the modified sandpile model and partial discharge data obtained in experiments confirms the existence of self-organized criticality in electrical treeing.

  1. Tree rings, carbon dioxide, and climatic change

    Microsoft Academic Search

    GORDON C. JACOBY; ROSANNE D. D'ARRIGO

    1997-01-01

    Tree rings have been used in various appli- cations to reconstruct past climates as well as to assess the effects of recent climatic and environmental change on tree growth. In this paper we brief ly review two ways that tree rings provide information about climate change and CO2 :( i )i n determining whether recent warming during the period of

  2. Improving decision trees for acoustic modeling

    Microsoft Academic Search

    Ariane Lazaridès; Yves Normandin; Roland Kuhn

    1996-01-01

    In the last few years, the power and simplicity of classification trees as acoustic modeling tools have gained them much popularity. In (1), we studied ''tree units'', which cluster parameters at the HMM level. Building on this earlier work, we examine some new variants of Young et al's ''tree states'', which cluster parameters at the state level (2). We have

  3. Original article Carbon balance and tree growth

    E-print Network

    Boyer, Edmond

    from leaf to crown and to tree scale, 2) to determine the pro- portion of assimilated carbon used crown classes (dominant, codominant and intermediate trees). A nonlinear relationship between net CO2Original article Carbon balance and tree growth in a Fagus sylvatica stand Stéphanie Lebaubea, Noël

  4. "Dangerous" urban trees & community health & safety

    E-print Network

    "Dangerous" urban trees & community health & safety Norman Dandy Forest Research #12;Urban trees against immediate threats to human health and safety, but weak governance to protect against longer are removed for health and safety reasons" (London Assembly 2007: 4) · falling branches / trees, · tripping

  5. Avoiding Differences Spanning Trees in Grid Graphs

    E-print Network

    Zeilberger, Doron

    Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Automated Proof and Discovery #12;Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Automated Proof and Discovery #12;Avoiding Differences Spanning Trees in Grid Graphs The Firefighter Problem Outline 1 Avoiding

  6. Generating trees and proper Riordan Arrays

    Microsoft Academic Search

    Donatella Merlini; M. Cecilia Verri

    2000-01-01

    We use an algebraic approach to study the connection between generating trees andproper Riordan Arrays deriving a theorem that, under suitable conditions, associatesa Riordan Array to a generating tree and vice versa. Thus, we can use results fromthe theory of Riordan Arrays to study properties of generating trees. In particular, wecan find, in a general and easy way, the generating

  7. Responses of tree populations to climatic change

    Microsoft Academic Search

    Linda B. Brubaker

    1986-01-01

    The influence of climate on the population dynamics of trees must be inferred from indirect sources of information because the long lifespans of trees preclude direct observation of population growth and decline. Important insights about these processes come from 1) observations of the life histories and ecologies of trees in contemporary forests, 2) evidence of recent treeline movements in remote

  8. Diagnostic expert systems from dynamic fault trees

    Microsoft Academic Search

    Tariq Assaf; Joanne Bechta Dugan

    2004-01-01

    A methodology for developing a diagnostic map for systems that can be analyzed via a dynamic fault tree is proposed in this paper. This paper shows how to automatically design a diagnostic decision tree from a dynamic fault tree used for reliability analysis. In particular the methodology makes use of Markov chains since they are mathematical models used for reliability

  9. A survey of decision tree classifier methodology

    Microsoft Academic Search

    S. Rasoul Safavian; David Landgrebe

    1991-01-01

    A survey is presented of current methods for decision tree classifier (DTC) designs and the various existing issues. After considering potential advantages of DTCs over single-state classifiers, the subjects of tree structure design, feature selection at each internal node, and decision and search strategies are discussed. The relation between decision trees and neutral networks (NN) is also discussed

  10. Fault Tree Analysis Using Bit Manipulation

    Microsoft Academic Search

    Dean B. Wheeler; Jason S. Hsuan; Ralph R. Duersch; Glenn M. Roe

    1977-01-01

    This paper describes an efficient technique for computerized fault-tree analysis. The technique is based upon binary coding of events and bit manipulation for tree reduction, reducing both computation time and computer storage requirements. The operations include generation of minimal cut sets for trees containing arbitrary AND and OR logic, and determination of top event existence probability for s-independent minimal cut

  11. Formal Fault Tree Analysis: Practical Experiences

    E-print Network

    Paris-Sud XI, Université de

    AVoCS 2006 Formal Fault Tree Analysis: Practical Experiences Frank Ortmeier Gerhard Schellhorn spread safety analysis methods: fault tree analysis (FTA). Formal FTA allows to rigorously reason about FTA by using model checking. Keywords: fault tree analysis, dependability, safety analysis, formal

  12. A data structure for dynamic trees

    Microsoft Academic Search

    Daniel Dominic Sleator; Robert Endre Tarjan

    1981-01-01

    We propose a data structure to maintain a collection of vertex-disjoint trees under a sequence of two kinds of operations: a link operation that combines two trees into one by adding an edge, and a cut operation that divides one tree into two by deleting an edge. Our data structure requires O(log n) time per operation when the time is

  13. CSCI2010U Laboratory #8 Binary Trees

    E-print Network

    Bradbury, Jeremy S.

    CSCI2010U ­ Laboratory #8 Binary Trees Introduction This lab has one activity that relates to programming binary trees. To complete this lab you will need to visit the course website and download the required Lab 8 resources: · BTNode.java · BinaryTree.java · Demo.java Activity 1: Add a new method called

  14. EXCEPTIONALLY SMALL BALLS IN STABLE TREES

    E-print Network

    Paris-Sud XI, Université de

    EXCEPTIONALLY SMALL BALLS IN STABLE TREES Thomas Duquesne Guanying Wang November 14, 2011 Abstract The -stable trees are random measured compact metric spaces that appear as the scaling limit of Galton-Watson trees whose offspring distribution lies in a -stable domain, (1, 2]. They form a specific class

  15. On some varieties associated with trees

    E-print Network

    Paris-Sud XI, Université de

    On some varieties associated with trees F. Chapoton March 3, 2014 Abstract This article considers some affine algebraic varieties attached to finite trees and closely related to cluster algebras. Their definition involves a canonical coloring of vertices of trees into three colors. These varieties are proved

  16. Genomics of Tropical Fruit Tree Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genetic improvement of tropical fruit trees is limited when compared to progress achieved in temperate fruit trees and annual crops. Tropical fruit tree breeding programs require significant resources to develop new cultivars that are adapted to modern shipping and storage requirements. The use...

  17. Large-Scale Inference of Phylogenetic Trees

    E-print Network

    Poirazi, Yiota

    Large-Scale Inference of Phylogenetic Trees Alexandros Stamatakis Institute of Computer Science Trees Alexandros Stamatakis As of July 1st 2006 Swiss Institute of Bioinformatics at Lausanne #12 Tree-of-life New insights in medical & biological research #12;© Alexandros Stamatakis, March 2006 7

  18. Aronszajn Trees and the SCH Itay Neeman

    E-print Network

    Andrews, Peter B.

    Aronszajn Trees and the SCH Itay Neeman and Spencer Unger February 28, 2009 1 Introduction such that the Singular Cardinal Hypothesis fails at and the tree property holds at + . The purpose of these notes. We begin with a discussion of trees, which are natural objects in infinite combinatorics. One topic

  19. TREE MAINTENANCE AND REMOVAL Table Of Contents

    E-print Network

    US Army Corps of Engineers

    EM 385-1-1 XX Sep 13 i Section 31 TREE MAINTENANCE AND REMOVAL Table Of Contents Section: Page 31.A General................... ......................................................31-1 31.B Tree Climbing.................................31-14 #12;EM 385-1-1 XX Sep 13 31-1 SECTION 31 TREE MAINTENANCE AND REMOVAL 31. A GENERAL 31.A.01

  20. Hardwood Tree Improvement and Regeneration Center

    E-print Network

    FNR-213 Hardwood Tree Improvement and Regeneration Center North Central Research Station USDA Forest Service Department of Forestry and Natural Resources Purdue University Designing Hardwood Tree Woody plants can be of value to many wildlife species. The species of tree or shrub, or the location

  1. Generating Production Rules from Decision Trees

    Microsoft Academic Search

    J. Ross Quinlan

    1987-01-01

    Many inductive knowledge acquisition algorithms generate clas­ sifiers in the form of decision trees. This paper describes a tech­ nique for transforming such trees to small sets of production rules, a common formalism for expressing knowledge in expert systems. The method makes use of the training set of cases from which the decision tree was generated, first to generalize and

  2. Malcolm Guite The Magic Apple Tree

    E-print Network

    Robertson, Stephen

    Malcolm Guite The Magic Apple Tree Someday make a journey through the rain Through sodden streets in darkening December A journey to the magic apple tree. And journey also, darkling, through your past Journey records. You glimpsed it once within the garden wall, The image of an ancient apple tree, The fall

  3. Fault tree analysis with fuzzy gates

    Microsoft Academic Search

    HanSuk Pan; WonYoung Yun

    1997-01-01

    Fault tree analysis is an important tool analyzing system reliability. Fault trees consist of gates and events. Gates mean relationships between events. In fault tree analysis, AND, OR gates have been used as typical gates but it is often difficult to model the system structure with the two gates because in many cases we have not exact knowledge on system

  4. Trees 1 2004 Goodrich, Tamassia Make Money Fast!

    E-print Network

    Alechina, Natasha

    Trees 1© 2004 Goodrich, Tamassia Trees Make Money Fast! Stock Fraud Ponzi Scheme Bank Robbery #12;Trees 2© 2004 Goodrich, Tamassia What is a Tree In computer science, a tree is an abstract model of a hierarchical structure A tree consists of nodes with a parent-child relation (at most one parent!) Applications

  5. RECONCILED TREES 1 Submitted to Molecular Phylogeny and Evolution

    E-print Network

    Page, Roderic

    RECONCILED TREES 1 Submitted to Molecular Phylogeny and Evolution Please address all correspondence trees From Gene to Organismal Phylogeny: Reconciled Trees and the Gene Tree/Species Tree Problem RODERIC of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, U.K. #12;RECONCILED TREES 2

  6. Red-Black Trees 11/11/2004 10:02 AM Red-Black Trees 1 2004 Goodrich, Tamassia

    E-print Network

    Alechina, Natasha

    Red-Black Trees 11/11/2004 10:02 AM 1 Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison

  7. Red-Black Trees 11/26/2007 11:09 AM Red-Black Trees 1 2004 Goodrich, Tamassia

    E-print Network

    Alechina, Natasha

    Red-Black Trees 11/26/2007 11:09 AM 1 Red-Black Trees 1© 2004 Goodrich, Tamassia Red-Black Trees 6 3 8 4 v z Red-Black Trees 2© 2004 Goodrich, Tamassia From (2,4) to Red-Black Trees A red-black tree is a representation of a (2,4) tree by means of a binary tree whose nodes are colored red or black In comparison

  8. Planting Kurepa Trees And Killing Jech Kunen Trees In a Model By Using One Inaccessible Cardinal 1

    E-print Network

    Jin, Renling

    Planting Kurepa Trees And Killing Jech Kunen Trees In a Model By Using One Inaccessible Cardinal 1 Saharon Shelah2 and Renling Jin Abstract By an !1 tree we mean a tree of power !1 and height !1 . Under CH and 2!1 !2 we call an !1 tree a Jech Kunen tree if it has many branches for some strictly between !1

  9. Anatomical modeling of the bronchial tree

    NASA Astrophysics Data System (ADS)

    Hentschel, Gerrit; Klinder, Tobias; Blaffert, Thomas; Bülow, Thomas; Wiemker, Rafael; Lorenz, Cristian

    2010-02-01

    The bronchial tree is of direct clinical importance in the context of respective diseases, such as chronic obstructive pulmonary disease (COPD). It furthermore constitutes a reference structure for object localization in the lungs and it finally provides access to lung tissue in, e.g., bronchoscope based procedures for diagnosis and therapy. This paper presents a comprehensive anatomical model for the bronchial tree, including statistics of position, relative and absolute orientation, length, and radius of 34 bronchial segments, going beyond previously published results. The model has been built from 16 manually annotated CT scans, covering several branching variants. The model is represented as a centerline/tree structure but can also be converted in a surface representation. Possible model applications are either to anatomically label extracted bronchial trees or to improve the tree extraction itself by identifying missing segments or sub-trees, e.g., if located beyond a bronchial stenosis. Bronchial tree labeling is achieved using a naïve Bayesian classifier based on the segment properties contained in the model in combination with tree matching. The tree matching step makes use of branching variations covered by the model. An evaluation of the model has been performed in a leaveone- out manner. In total, 87% of the branches resulting from preceding airway tree segmentation could be correctly labeled. The individualized model enables the detection of missing branches, allowing a targeted search, e.g., a local rerun of the tree-segmentation segmentation.

  10. On finding minimum-diameter clique trees

    SciTech Connect

    Blair, J.R.S. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science); Peyton, B.W. (Oak Ridge National Lab., TN (United States))

    1991-08-01

    It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-diameter clique tree. The new algorithm is an analogue of the natural greedy algorithm for rooting an ordinary tree in order to minimize its height. It has potential application in the development of parallel algorithms for both knowledge-based systems and the solution of sparse linear systems of equations. 31 refs., 7 figs.

  11. Extremal properties of random trees

    NASA Astrophysics Data System (ADS)

    Ben-Naim, E.; Krapivsky, P. L.; Majumdar, Satya N.

    2001-09-01

    We investigate extremal statistical properties such as the maximal and the minimal heights of randomly generated binary trees. By analyzing the master evolution equations we show that the cumulative distribution of extremal heights approaches a traveling wave form. The wave front in the minimal case is governed by the small-extremal-height tail of the distribution, and conversely, the front in the maximal case is governed by the large-extremal-height tail of the distribution. We determine several statistical characteristics of the extremal height distribution analytically. In particular, the expected minimal and maximal heights grow logarithmically with the tree size, N, hmin~vmin ln N, and hmax~vmax ln N, with vmin=0.373365... and vmax=4.31107..., respectively. Corrections to this asymptotic behavior are of order O(ln ln N).

  12. Organic & Integrated Tree Fruit Production

    NSDL National Science Digital Library

    Part of the Washington State University Tree Fruit Research and Extension Center, this website offers various resources for orchardists interested in organic and integrated production methods. The site contains sections on Organic Fruit Production, Soil and Pest Management, Apple Replant Disease, and more. The site also offers links to other Washington State University sites for Horticulture, Entomology, Fruit Pathology, and Postharvest resources. Many of the documents on this site are available for download as PDF files.

  13. Factoring with the Factor Tree

    NSDL National Science Digital Library

    Interactive Math Miscellany and Puzzles, Alexander Bogomolny

    2011-01-01

    This Java applet presents a composite number, and prompts you to factor it -- one step at a time. Enter one factor, prime or another composite; the applet calculates the remaining factor, and branches two boxes below any composite factor so that you may proceed factoring until you obtain the full factorization into primes, which the applet colors in green. Click the "Repeat problem" button to see that different factor trees for a given number still result in the same prime factorization.

  14. Binomial trees as dynamical systems

    NASA Astrophysics Data System (ADS)

    Galeeva, Roza

    2001-03-01

    One of the simplest and very popular techniques for pricing an option or other derivative involves constructing what is known as a binomial tree. This is a tree which represents the possible paths, that might be followed by the underlying assets price. We will view this tree as a dynamical system, which means that we specify a space, and a map acting on it. Here the space will be the space of all possible paths, and the corresponding map will be the shift on each path. Such approach reveals a dynamical nature of certain financial terms and financial principles. For example, returns along a path could be defined by a potential, and the price on each path is expressed in a very “dynamical” fashion. Using this interpretation, we introduce a new characteristic as the pressure of the potential of returns. Under the conditions of no arbitrage, the pressure has to be equal to be the interest rate. This gives a new formulation of the no arbitrage principle: the expected price has to be finite: a smaller or greater discount would give either very small (zero at the limit), or very large (at the limit infinity) price. Therefore, the presented work links the discrete models of option pricing to the thermodynamical formalism and multifractal analysis of invariant sets in dynamical systems.

  15. Phytoremediation of trichloroethene (TCE) using cottonwood trees

    USGS Publications Warehouse

    Jones, S.A.; Lee, R.W.; Kuniansky, E.L.

    1999-01-01

    The ability of cottonwood trees for phytoremediation was studied on aerobic shallow groundwater containing TCE. Cottonwood trees were planted over a 0.2-ha area at the Naval Air Station at Fort Worth, TX, in April 1996. Two years later, groundwater chemistry in the terrace alluvial aquifer was changing locally. Dissolved oxygen (DO) concentrations declined at the southern end of the whip plantings while total iron concentration increased. Groundwater chemistry near a mature cottonwood tree ~ 60 m from the caliper trees was different from that observed elsewhere. Anaerobic conditions near the mature cottonwood tree were evident. Reductive dechlorination of TCE occurred in the aquifer near the mature tree, as demonstrated by very small concentration of TCE in groundwater, a small median ratio of TCE to the degradation product cis-1,2-DCE and the presence of vinyl chloride.

  16. Alternative fire resistance strategies in savanna trees

    Microsoft Academic Search

    Jacques Gignoux; Jean Clobert; Jean-Claude Menaut

    1997-01-01

    Bark properties (mainly thickness) are usually presented as the main explanation for tree survival in intense fires. Savanna\\u000a fires are mild, frequent, and supposed to affect tree recruitment rather than adult survival: trunk profile and growth rate\\u000a of young trees between two successive fires can also affect survival. These factors and fire severity were measured on a sample\\u000a of 20

  17. Decision Tree Induction from Numeric Data Stream

    Microsoft Academic Search

    Satoru Nishimura; Masahiro Terabe; Kazuo Hashimoto

    2008-01-01

    Hoeffding Tree Algorithm is known as a method to induce decision trees from a data stream. Treatment of numeric attribute\\u000a on Hoeffding Tree Algorithm has been discussed for stationary input. It has not yet investigated, however, for non-stationary\\u000a input where the effect of concept drift is apparent. This paper identifies three major approaches to handle numeric values,\\u000a Exhaustive Method, Gaussian

  18. Faster algorithm for optimum Steiner trees

    E-print Network

    Vygen, Jens

    deterministic algorithm for the Steiner tree prob- lem in weighted graphs. Its running time is O(nk2k+log2 k log previously known algorithms if 2 log n(log log n)3 log2 n)/2. Our algorithm is based on a new tree Subject Classification: 90C27, 90C39, 05C05 1 Introduction We consider the well-known Steiner tree problem

  19. q-gram matching using tree models

    Microsoft Academic Search

    Prahlad Fogla; Wenke Lee

    2006-01-01

    q-gram matching is used for approximate substring matching problems in a wide range of application areas, including intrusion detection. In this paper, we present a tree-based model to perform fast linear time q-gram matching. All q-grams present in the text are stored in a tree structure similar to trie. We use a tree redundancy pruning algorithm to reduce the size

  20. Immunological Analysis of Allergenic Tree Nut Proteins

    Microsoft Academic Search

    LeAnna N. Willison

    2009-01-01

    Allergies are a growing problem in industrialized countries, with food allergies affecting 6% of children and 3-4% of adults. Tree nuts are a common cause of food-induced allergy and include walnut, cashew, almond, hazelnut, pistachio, pecan, chestnut, and Brazil nut. Tree nut allergy, in particular, affects 0.5% of the US population. Unlike other food allergies, tree nut allergy persists throughout

  1. Hibernation by tree-roosting bats

    Microsoft Academic Search

    Christopher Turbill; Fritz Geiser

    2008-01-01

    In summer, long-eared bats (Nyctophilus spp.) roost under bark and in tree cavities, where they appear to benefit from diurnal heating of roosts. In contrast, hibernation\\u000a is thought to require a cool stable temperature, suggesting they should prefer thermally insulated tree cavities during winter.\\u000a To test this prediction, we quantified the winter thermoregulatory physiology and ecology of hibernating tree-roosting bats,

  2. Phillips goes subsea trees in Ivory Coast

    SciTech Connect

    Bryngelson, R.H.

    1982-11-15

    Describes installation of 3 wet, diver-assist trees, in the Espoir field offshore Ivory Coast, as part of Phillips Petroleum's plans to use 5 satellite wells with downhole completion equipment and subsea production trees. Simplicity in design and attention to training has resulted in an installation time of about 3 weeks for one of the largest subsea trees in the industry. Presents diagram showing the converted jackup, Dan Duke drilling unit, which supports equipment to handle production from subsea wells.

  3. Reconciliation with Non-Binary Species Trees

    PubMed Central

    Vernot, Benjamin; Stolzer, Maureen; Goldman, Aiton

    2008-01-01

    Abstract Reconciliation extracts information from the topological incongruence between gene and species trees to infer duplications and losses in the history of a gene family. The inferred duplication-loss histories provide valuable information for a broad range of biological applications, including ortholog identification, estimating gene duplication times, and rooting and correcting gene trees. While reconciliation for binary trees is a tractable and well studied problem, there are no algorithms for reconciliation with non-binary species trees. Yet a striking proportion of species trees are non-binary. For example, 64% of branch points in the NCBI taxonomy have three or more children. When applied to non-binary species trees, current algorithms overestimate the number of duplications because they cannot distinguish between duplication and incomplete lineage sorting. We present the first algorithms for reconciling binary gene trees with non-binary species trees under a duplication-loss parsimony model. Our algorithms utilize an efficient mapping from gene to species trees to infer the minimum number of duplications in O(|VG| · (kS + hS)) time, where |VG| is the number of nodes in the gene tree, hS is the height of the species tree and kS is the size of its largest polytomy. We present a dynamic programming algorithm which also minimizes the total number of losses. Although this algorithm is exponential in the size of the largest polytomy, it performs well in practice for polytomies with outdegree of 12 or less. We also present a heuristic which estimates the minimal number of losses in polynomial time. In empirical tests, this algorithm finds an optimal loss history 99% of the time. Our algorithms have been implemented in Notung, a robust, production quality, tree-fitting program, which provides a graphical user interface for exploratory analysis and also supports automated, high-throughput analysis of large data sets. PMID:18808330

  4. Quantum Verification of Minimum Spanning Tree

    E-print Network

    Mark Heiligman

    2011-12-05

    Previous studies has shown that for a weighted undirected graph having $n$ vertices and $m$ edges, a minimal weight spanning tree can be found with $O^*(\\sqrt{mn})$ calls to the weight oracle. The present note shows that a given spanning tree can be verified to be a minimal weight spanning tree with only $O(n\\bigr)$ calls to the weight oracle and $O(n+\\sqrt{m}\\log n)$ total work.

  5. Tutorial: Advanced fault tree applications using HARP

    NASA Technical Reports Server (NTRS)

    Dugan, Joanne Bechta; Bavuso, Salvatore J.; Boyd, Mark A.

    1993-01-01

    Reliability analysis of fault tolerant computer systems for critical applications is complicated by several factors. These modeling difficulties are discussed and dynamic fault tree modeling techniques for handling them are described and demonstrated. Several advanced fault tolerant computer systems are described, and fault tree models for their analysis are presented. HARP (Hybrid Automated Reliability Predictor) is a software package developed at Duke University and NASA Langley Research Center that is capable of solving the fault tree models presented.

  6. LISP-based fault tree development environment

    SciTech Connect

    Dixon, B.W.

    1986-01-01

    This paper describes an integrated graphical environment which can be used to build, modify, and analyze fault trees on a stand-alone work-station. The environment is written in LISP, utilizing graphics and menu features commonly found on LISP workstations. A unique fault tree solution algorithm is presented that efficiently utilizes a list-based tree structure and search space, and rule-based pruning to allow for rapid analysis of larger trees. Design and efficiency issues are discussed. 5 refs., 11 figs.

  7. Why are so many trees hollow?

    PubMed

    Ruxton, Graeme D

    2014-11-01

    In many living trees, much of the interior of the trunk can be rotten or even hollowed out. Previously, this has been suggested to be adaptive, with microbial or animal consumption of interior wood producing a rain of nutrients to the soil beneath the tree that allows recycling of those nutrients into new growth via the trees roots. Here I propose an alternative (non-exclusive) explanation: such loss of wood comes at very little cost to the tree and so investment in costly chemical defence of this wood is not economic. I discuss how this theory can be tested empirically. PMID:25392312

  8. Progress in the biotechnology of trees.

    PubMed

    Hammatt, N

    1992-07-01

    An increasing world population and rise in demand for tree products, especially wood, has increased the need to produce more timber through planting more forest with improved quality stock. Superior trees are likely to arise from several sources. Firstly, forest trees can be selected from wild populations and cloned using macropropagation techniques already being investigated for fruit tree rootstocks. Alternatively, propagation might be brought aboutin vitro through micropropagation or sustained somatic embryogenesis, with encapsulation of the somatic embryos to form artificial seeds. Tree quality could be improved through increased plant breeding and it is likely that experienced gained, to date, in the breeding of fruit species will be useful in devising strategies for forest trees. Since the development of techniques to regenerate woody plants from explant tissues, cells and protoplasts, it is now feasible to test the use of tissue culture methods to bring about improvements in tree quality. Success has already been achieved for tree species in the generation of somaclonal and protoclonal variation, the formation of haploids, triploids and polyploids, somatic hybrids and cybrids and the introduction of foreign DNA through transformation. This review summarizes the advances made so far in tree biotechnology, and suggests some of the directions that it might take in the future. PMID:24425505

  9. University of Oregon Atlas of Trees

    E-print Network

    Oregon, University of

    University of Oregon MAP DESIGN AND DEVELOPMENT Jim Meacham, Ken Kato, Grace Gardner, Jacob Blair, Erik Howard PRODUCTION Printing and Mailing Services University of Oregon TREE SILHOUETTE ILLUSTRATIONS

  10. Magnetic Measurements on Maple and Sequoia Trees

    Microsoft Academic Search

    Gunther Kletetschka

    \\u000a Magnetic measurements of soil and tree bark adjacent to a busy highway revealed a significant variation in the concentration\\u000a of magnetic particles with distance from the highway. Furthermore, forest-facing tree-bark contains significantly more magnetic\\u000a particles than road-facing tree-bark. Magnetic particles were detected both on the bark of the maple trees and in the first\\u000a centimeter of the soil cover (O\\/A

  11. Photographic sensing of boron and chloride toxicities of citrus trees

    Microsoft Academic Search

    R. Cardenas; A. Paynado; H. W. Gausman; A. H. Gerbermann; R. L. Bowen

    1971-01-01

    Film density measurements were used to discriminate between healthy Red Blush grapefruit trees and trees whose foliage exhibited boron (B) and chloride (Cl⁻) toxicity symptoms (affected). Citrus trees were photographed from an aircraft (3000 ft altitude) and a Truco's aerial lift (9 ft above trees) with a Hasselblad camera. Light reflectance of foliage of B⁻ and Cl⁻-affected trees produced pinkish

  12. Time Optimal Left to Right Construction of Position Trees

    Microsoft Academic Search

    M. Kempf; Rudolf Bayer; Ulrich Güntzer

    1987-01-01

    In the following paper we are presenting a new algorithm for the on-line construction of position trees. Reading a given input string from left to right we are generating its position tree with the aid of the general concept of infix trees. An additional chain structure within the trees, called tail node connection, enables us to construct the tree within

  13. Identifying species of individual trees using airborne laser scanner

    Microsoft Academic Search

    Johan Holmgren; Åsa Persson

    2004-01-01

    Individual trees can be detected using high-density airborne laser scanner data. Also, variables characterizing the detected trees such as tree height, crown area, and crown base height can be measured. The Scandinavian boreal forest mainly consists of Norway spruce (Picea abies L. Karst.), Scots pine (Pinus sylvestris L.), and deciduous trees. It is possible to separate coniferous from deciduous trees

  14. Hierarchical Minimum Spanning Trees for Lossy Image Set Compression

    E-print Network

    Cheng, Howard

    tree is significantly lower than the previous minimum spanning tree algorithms. 1 Introduction spanning tree algorithms have been proposed for the lossy compression of image sets. In these algorithms spanning tree algorithm in which the minimum spanning tree algorithm is first applied to clusters

  15. 41TREE CARE INDUSTRY -DECEMBER 2001 Plant Health Care

    E-print Network

    41TREE CARE INDUSTRY - DECEMBER 2001 Plant Health Care Why Do Trees Vary in Suitability to Insects relationships among tree food quality to in- sects and pathogens, the environment and tree growth rates. The articles are based on a paper presented at "Trees 2000: Challenges for the future," a conference or

  16. Scalable Tree Aggregation for Multicast Alexandre GUITTON and Joanna MOULIERAC

    E-print Network

    Paris-Sud XI, Université de

    Scalable Tree Aggregation for Multicast Alexandre GUITTON and Joanna MOULIERAC IRISA. In this paper, we propose an algorithm called STA (Scalable Tree Aggrega- tion) which reduces the number of trees by allowing several groups to be aggregated to the same tree: the less trees, the less forwarding

  17. Connected tree-width Reinhard Diestel and Malte Muller

    E-print Network

    Diestel, Reinhard

    Connected tree-width Reinhard Diestel and Malte M¨uller November 8, 2014 Abstract The connected tree-width of a graph is the minimum width of a tree- decomposition whose parts induce connected subgraphs. Long cycles are examples of graphs that have small tree-width but large connected tree-width. We

  18. The Trade-offs of Multicast Trees and Algorithms

    Microsoft Academic Search

    Liming Wei; Deborah Estrin

    1995-01-01

    Multicast trees can be shared across sources (shared trees) or may be source-specific (shortest pathtrees). Inspired by recent interests in using shared trees for interdomain multicasting, we investigate thetrade-offs among shared tree types and source specific shortest path trees, by comparing performanceover both individual multicast group and the whole network. The performance is evaluated in termsof path length, link cost,

  19. Estimating tree height and tree crown properties using airborne scanning laser in a boreal nature reserve

    Microsoft Academic Search

    Erik Næsset; Tonje Økland

    2002-01-01

    Tree height, the height from the ground surface to the tree crown, and the crown length as a proportion of tree height of individual trees were derived from various canopy height metrics measured by a small-footprint airborne laser scanner flown over a boreal forest reserve. The average spacing on the ground of the laser pulses ranged from 0.66 to 1.29

  20. Tree rings in the tropics: a study on growth and ages of Bolivian rain forest trees

    Microsoft Academic Search

    Roel Jacobus Wilhelmus Brienen

    2005-01-01

    Detailed information on long-term growth rates and ages of tropical rain forest trees is important to obtain a better understanding of the functioning of tropical rain forests. Nevertheless, little is known about long-term growth or ages of tropical forest trees, due to a supposed lack of annual tree rings in most tropical tree species. Aim of this PhD thesis was

  1. Transpiration and whole-tree conductance in ponderosa pine trees of different heights

    Microsoft Academic Search

    Michael G. Ryan; Barbara J. Bond; Beverly E. Law; Robert M. Hubbard; David Woodruff; Emil Cienciala; Jiri Kucera

    2000-01-01

    Changes in leaf physiology with tree age and size could alter forest growth, water yield, and carbon fluxes. We measured tree\\u000a water flux (Q) for 14 ponderosa pine trees in two size classes (12 m tall and ?40 years old, and 36 m tall and ? 290 years old) to determine\\u000a if transpiration (E) and whole-tree conductance (g\\u000a t) differed

  2. Understory plant communities and the functional distinction between savanna trees, forest trees, and pines.

    SciTech Connect

    Veldman, Joseph, W., Mattingly, Brett, W., Brudvig, Lars, A.

    2013-04-01

    Abstract. Although savanna trees and forest trees are thought to represent distinct functional groups with different effects on ecosystem processes, few empirical studies have examined these effects. In particular, it remains unclear if savanna and forest trees differ in their ability to coexist with understory plants, which comprise the majority of plant diversity in most savannas. We used structural equation modeling (SEM) and data from 157 sites across three locations in the southeastern United States to understand the effects of broadleaf savanna trees, broadleaf forest trees, and pine trees on savanna understory plant communities. After accounting for underlying gradients in fire frequency and soil moisture, abundances (i.e., basal area and stem density) of forest trees and pines, but not savanna trees, were negatively correlated with the cover and density (i.e., local-scale species richness) of C4 graminoid species, a defining savanna understory functional group that is linked to ecosystem flammability. In analyses of the full understory community, abundances of trees from all functional groups were negatively correlated with species density and cover. For both the C4 and full communities, fire frequency promoted understory plants directly, and indirectly by limiting forest tree abundance. There was little indirect influence of fire on the understory mediated through savanna trees and pines, which are more fire tolerant than forest trees. We conclude that tree functional identity is an important factor that influences overstory tree relationships with savanna understory plant communities. In particular, distinct relationships between trees and C4 graminoids have implications for grass-tree coexistence and vegetation-fire feedbacks that maintain savanna environments and their associated understory plant diversity.

  3. The Tree of Animal Life

    NSDL National Science Digital Library

    Stan Braude

    2007-09-01

    The Tree of Animal Life activity is a simple, sorting exercise that can help them see a bigger picture. The activity sets the stage for learning about animal taxonomy and introduces the characteristics of various animal groups in a general way. Though the activity doesn't teach about each animal group's characteristics in great detail, the process of sorting of atypical examples (e.g., bat, octopus) does spark interesting discussions among students on the differences between animals and how scientists classify them. I've conducted the activity with students of various ages.

  4. Selective limb pruning, tree removal, and paclobutrazol growth retardant for crowding pecan trees

    Microsoft Academic Search

    Ray E. Worley; Ben G. Mullinix; Jeff W. Daniel

    1996-01-01

    Selective limb pruning, tree thinning, and the combination of selective limb pruning and paclobutrazol application as a basal drench were used to reduce overcrowding of pecan [Carya illinoensis (Wangenh.) C. Koch] trees. Thinning increased yield per tree for the cultivar ‘Desirable’ and did not significantly reduce yield per hectare during the 7 year period of the study. None of the

  5. Trees in Bangladesh paddy fields. 2. Survival of trees planted in crop fields

    Microsoft Academic Search

    D. Hocking; K. Islam

    1995-01-01

    The design and methods are described of farmer-managed action-research to test the survival and performance of trees planted in paddy fields of private farms in Bangladesh. Farmers received seedlings of indigenous and exotic trees with extension advice on planting methods and care. Planting was done in systematically designed randomized modules involving twelve thousand trees up to the end of 1990.

  6. Atlas of United States Trees, Volume 2: Alaska Trees and Common Shrubs.

    ERIC Educational Resources Information Center

    Viereck, Leslie A.; Little, Elbert L., Jr.

    This volume is the second in a series of atlases describing the natural distribution or range of native tree species in the United States. The 82 species maps include 32 of trees in Alaska, 6 of shrubs rarely reaching tree size, and 44 more of common shrubs. More than 20 additional maps summarize environmental factors and furnish general…

  7. The relation between tree size complexity and probability for Boolean functions generated by uniform random trees.$

    E-print Network

    Gittenberger, Bernhard

    The relation between tree size complexity and probability for Boolean functions generated Abstract We consider a probability distribution on the set of Boolean functions in n variables which the tree size complexity and the probability of a function. This is done by first expressing trees

  8. LS(Graph & Tree): A Local Search Framework for Constraint Optimization on Graphs and Trees

    E-print Network

    Deville, Yves

    LS(Graph & Tree): A Local Search Framework for Constraint Optimization on Graphs and Trees Pham University Providence, RI 02912, USA pvh@cs.brown.edu ABSTRACT LS(Graph & Tree) is a local search framework which aims at simplifying the modeling of Constraint Satisfaction Opti- mization Problems on graphs

  9. BlobTree Trees Callum Galbraith Peter MacMurchy Brian Wyvill

    E-print Network

    Wyvill, Brian

    BlobTree Trees Callum Galbraith Peter MacMurchy Brian Wyvill Department of Computer Science branches, and not all of the observed phenom- ena can be represented by current methods. Many tree types exhibit non-smooth features such as branch bark ridges and collars. In this research a hierarchical

  10. Figure 1a. A tree that is not pruned when young may grow into an unattractive tree.

    E-print Network

    Balasundaram, Balabhaskar "Baski"

    Figure 1a. A tree that is not pruned when young may grow into an unattractive tree. Figure 1b. A tree that is pruned when young grows into a strong, attractive tree. Division of Agricultural Sciences available on our website at: http://osufacts.okstate.edu Proper pruning when a tree is young will ultimately

  11. Street tree valuation systems Street trees and urban woodlands provide a number of environmental and social benefits, including contributing to

    E-print Network

    Street tree valuation systems Street trees and urban woodlands provide a number of environmental value of street trees: CAVAT, Helliwell and i-Tree. The review showed that the three valuation systems low field data requirements. At the opposite end of the spectrum i-Tree requires data collected from

  12. What is i-TREE? i-TREE is a software suite that is designed to integrate

    E-print Network

    Schweik, Charles M.

    What is i-TREE? i-TREE is a software suite that is designed to integrate three Forest Service urban Community Tree Inventory (MCTI), and the Street Tree Resource Analysis Tool for Urban forest Managers (STRATUM). UFORE and STRATUM facilitate urban forest analysis at the ecosystem and street tree levels

  13. NatioNal tree Safety Group Guidance on trees and public safety in the uK

    E-print Network

    N T S G NatioNal tree Safety Group Guidance on trees and public safety in the uK for owners, managers and advisers Common sense risk management of trees #12;2 © Crown Copyright 2011 You may re eH12 7At. the National tree Safety Group Common sense risk management of trees Forestry Commission

  14. Parallel analog neural networks for tree searching

    NASA Astrophysics Data System (ADS)

    Saylor, Janet; Stork, David G.

    1986-08-01

    We have modeled parallel analog neural networks designed such that their evolution toward final states is equivalent to finding optimal (or nearly optimal) paths through decision trees. This work extends that done on the Traveling Salesman Problem (TSP)[1] and sheds light on the conditions under which analog neural networks can and cannot find solutions to discrete optimization problems. Neural networks show considerable specificity in finding optimal solutions for tree searches; in the cases when a final state does represent a syntactically correct path, that path will be the best path 70-90% of the time—even for trees with up to two thousand nodes. However, it appears that except for trivial networks lacking the ability to ``think globally,'' there exists no general network architecture that can strictly insure the convergence a state that represents a single, continuous, unambiguous path. In fact, we find that for roughly 15% of trees with six generations, 40% of trees with eight generations, and 70% of trees with ten generations, networks evolve to ``broken paths,'' i.e., combinations of the beginning of one and the end of another path through a tree. Tree searches illustrate well neural dynamics because tree structures make the effects of competition and positive feedback apparent. We have found that 1) convergence times for networks with up to 2000 neurons are very rapid, depend on the gain of neurons and magnitude of neural connections but not on the number of generations or branching factor of a tree, 2) all neurons along a ``winning'' path turn on exponentially with the same exponent, and 3) the general computational mechanism of these networks appears to be the pruning of a tree from the outer branches inward, as chain reactions of neurons being quenched tend to propagate along possible paths.

  15. Sulfur nutrition of deciduous trees

    NASA Astrophysics Data System (ADS)

    Herschbach, Cornelia; Rennenberg, Heinz

    2001-01-01

    Sulfur in its reduced form (-II) is an essential nutrient for growth and development, but is mainly available to plants in its oxidised form as sulfate. Deciduous trees take up sulfate by the roots from the soil solution and reduce sulfate to sulfide via assimilatory sulfate reduction in both roots and leaves. For reduction in the leaves, sulfate is loaded into the xylem and transported to the shoot. The surplus of sulfate not reduced in the chloroplast or stored in the vacuole and the surplus of reduced S not used for protein synthesis in the leaves is loaded into the phloem and transported back to the roots. Along the transport path, sulfate and glutathione (GSH) is unloaded from the phloem for storage in xylem and phloem parenchyma as well as in pit and ray cells. Re-mobilised S from storage tissues is loaded into the xylem during spring, but a phloem to xylem exchange does not appear to exist later in the season. As a consequence, a cycling pool of S was only found during the change of the seasons. The sulfate:glutathione ratio in the phloem seems to be involved in the regulation of S nutrition. This picture of S nutrition is discussed in relation to the different growth patterns of deciduous trees from the temperate climate zone, i.e. (1) terminated, (2) periodic and (3) indeterminate growth patterns, and in relation to environmental changes.

  16. Fast Tree: Computing Large Minimum-Evolution Trees with Profiles instead of a Distance Matrix

    SciTech Connect

    N. Price, Morgan; S. Dehal, Paramvir; P. Arkin, Adam

    2009-07-31

    Gene families are growing rapidly, but standard methods for inferring phylogenies do not scale to alignments with over 10,000 sequences. We present FastTree, a method for constructing large phylogenies and for estimating their reliability. Instead of storing a distance matrix, FastTree stores sequence profiles of internal nodes in the tree. FastTree uses these profiles to implement neighbor-joining and uses heuristics to quickly identify candidate joins. FastTree then uses nearest-neighbor interchanges to reduce the length of the tree. For an alignment with N sequences, L sites, and a different characters, a distance matrix requires O(N^2) space and O(N^2 L) time, but FastTree requires just O( NLa + N sqrt(N) ) memory and O( N sqrt(N) log(N) L a ) time. To estimate the tree's reliability, FastTree uses local bootstrapping, which gives another 100-fold speedup over a distance matrix. For example, FastTree computed a tree and support values for 158,022 distinct 16S ribosomal RNAs in 17 hours and 2.4 gigabytes of memory. Just computing pairwise Jukes-Cantor distances and storing them, without inferring a tree or bootstrapping, would require 17 hours and 50 gigabytes of memory. In simulations, FastTree was slightly more accurate than neighbor joining, BIONJ, or FastME; on genuine alignments, FastTree's topologies had higher likelihoods. FastTree is available at http://microbesonline.org/fasttree.

  17. Detecting coevolution without phylogenetic trees? Tree-ignorant metrics of coevolution perform as well as tree-aware metrics

    PubMed Central

    2008-01-01

    Background Identifying coevolving positions in protein sequences has myriad applications, ranging from understanding and predicting the structure of single molecules to generating proteome-wide predictions of interactions. Algorithms for detecting coevolving positions can be classified into two categories: tree-aware, which incorporate knowledge of phylogeny, and tree-ignorant, which do not. Tree-ignorant methods are frequently orders of magnitude faster, but are widely held to be insufficiently accurate because of a confounding of shared ancestry with coevolution. We conjectured that by using a null distribution that appropriately controls for the shared-ancestry signal, tree-ignorant methods would exhibit equivalent statistical power to tree-aware methods. Using a novel t-test transformation of coevolution metrics, we systematically compared four tree-aware and five tree-ignorant coevolution algorithms, applying them to myoglobin and myosin. We further considered the influence of sequence recoding using reduced-state amino acid alphabets, a common tactic employed in coevolutionary analyses to improve both statistical and computational performance. Results Consistent with our conjecture, the transformed tree-ignorant metrics (particularly Mutual Information) often outperformed the tree-aware metrics. Our examination of the effect of recoding suggested that charge-based alphabets were generally superior for identifying the stabilizing interactions in alpha helices. Performance was not always improved by recoding however, indicating that the choice of alphabet is critical. Conclusion The results suggest that t-test transformation of tree-ignorant metrics can be sufficient to control for patterns arising from shared ancestry. PMID:19055758

  18. Mitered Fractal Trees: Constructions and Properties Tom Verhoeff

    E-print Network

    Verhoeff, Tom

    trees as artwork (left: bronze; right: wood) Figure 1 shows two tree-shaped artworks, whose designs date of these trees have been constructed as artwork in wood and bronze. 1 Introduction Figure 1: Two mitered fractal

  19. M______ S________ '13 Working Title: Know Your Trees!

    E-print Network

    Snider, Barry B.

    M______ S________ '13 Working Title: Know Your Trees! Type of Project with the road leading from the Village to Rabb, ID all the trees, and then attach semi-permanent labels with each tree's Latin and English names. Each label

  20. THE WIENER INDEX OF SIMPLY GENERATED RANDOM TREES

    E-print Network

    Janson, Svante

    THE WIENER INDEX OF SIMPLY GENERATED RANDOM TREES moments as well as for the distribution of the Wiener index of a random tree from a simply generated family (or, equivalently, a critical Galton- Watson tree). We also establish a joint

  1. 16 CFR 501.2 - Christmas tree ornaments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Christmas tree ornaments. 501.2 Section 501.2 Commercial...PROHIBITIONS UNDER PART 500 § 501.2 Christmas tree ornaments. Christmas tree ornaments packaged and labeled for retail...

  2. 7 CFR 457.130 - Macadamia tree crop insurance provisions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Macadamia tree crop insurance provisions. 457.130 Section...INSURANCE REGULATIONS § 457.130 Macadamia tree crop insurance provisions. The macadamia tree crop insurance provisions for the 2011...

  3. 29 CFR 780.208 - Forest and Christmas tree activities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Forest and Christmas tree activities. 780.208 Section 780.208...Operations § 780.208 Forest and Christmas tree activities. Operations in a forest tree nursery such as seeding new beds and...

  4. 16 CFR 501.2 - Christmas tree ornaments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Christmas tree ornaments. 501.2 Section 501.2 Commercial...PROHIBITIONS UNDER PART 500 § 501.2 Christmas tree ornaments. Christmas tree ornaments packaged and labeled for retail...

  5. 16 CFR 501.2 - Christmas tree ornaments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Christmas tree ornaments. 501.2 Section 501.2 Commercial...PROHIBITIONS UNDER PART 500 § 501.2 Christmas tree ornaments. Christmas tree ornaments packaged and labeled for retail...

  6. 29 CFR 780.208 - Forest and Christmas tree activities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Forest and Christmas tree activities. 780.208 Section 780.208...Operations § 780.208 Forest and Christmas tree activities. Operations in a forest tree nursery such as seeding new beds and...

  7. 29 CFR 780.208 - Forest and Christmas tree activities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Forest and Christmas tree activities. 780.208 Section 780.208...Operations § 780.208 Forest and Christmas tree activities. Operations in a forest tree nursery such as seeding new beds and...

  8. 29 CFR 788.7 - “Planting or tending trees

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false âPlanting or tending trees.â 788.7 Section 788.7 Labor ...EMPLOYED § 788.7 “Planting or tending trees.” Employees employed in “planting or tending trees” include those engaged in...

  9. 29 CFR 788.7 - “Planting or tending trees

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false âPlanting or tending trees.â 788.7 Section 788.7 Labor ...EMPLOYED § 788.7 “Planting or tending trees.” Employees employed in “planting or tending trees” include those engaged in...

  10. 29 CFR 788.7 - “Planting or tending trees

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false âPlanting or tending trees.â 788.7 Section 788.7 Labor ...EMPLOYED § 788.7 “Planting or tending trees.” Employees employed in “planting or tending trees” include those engaged in...

  11. 7 CFR 457.130 - Macadamia tree crop insurance provisions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Macadamia tree crop insurance provisions. 457.130 Section...INSURANCE REGULATIONS § 457.130 Macadamia tree crop insurance provisions. The macadamia tree crop insurance provisions for the 2011...

  12. Trees from trees: construction of phylogenetic supertrees using clann.

    PubMed

    Creevey, Christopher J; McInerney, James O

    2009-01-01

    Supertree methods combine multiple phylogenetic trees to produce the overall best "supertree." They can be used to combine phylogenetic information from datasets only partially overlapping and from disparate sources (like molecular and morphological data), or to break down problems thought to be computationally intractable. Some of the longest standing phylogenetic conundrums are now being brought to light using supertree approaches. We describe the most widely used supertree methods implemented in the software program "clann" and provide a step by step tutorial for investigating phylogenetic information and reconstructing the best supertree. Clann is freely available for Windows, Mac and Unix/Linux operating systems under the GNU public licence at (http://bioinf.nuim.ie/software/clann). PMID:19378143

  13. Optimal Tree Approximation with Wavelets Richard Baraniuk

    E-print Network

    a pyramid or tree that represents signal structure from coarse to ne scales. Singularities are particularly simply represented: the energy from a singularity localizes along one branch of the tree (see Figure 1).1 To best process singularity-rich data, it is key that we match this persistence of singularity energy

  14. The use of classification trees for bioinformatics

    PubMed Central

    Chen, Xiang; Wang, Minghui; Zhang, Heping

    2011-01-01

    Classification trees are non-parametric statistical learning methods that incorporate feature selection and interactions, possess intuitive interpretability, are efficient, and have high prediction accuracy when used in ensembles. This paper provides a brief introduction to the classification tree-based methods, a review of the recent developments, and a survey of the applications in bioinformatics and statistical genetics. PMID:22523608

  15. The Arctic Tree Line and Climate Change

    E-print Network

    Blouin-Demers, Gabriel

    is the Arctic Tree Line? ­ A transition zone of vegetation ­ Divides the Arctic Tundra from the Forest Photo% higher on Tundra than Forest (J.Beringer et al., 2005) - Decreasing albedo because of increase in tree cover - Causes surface heating Forest Tundra Chapin et al., (2005), 10 Nadezhda et al., (2008) Albedo

  16. Adaptive aspects of tree crown geometry

    SciTech Connect

    Meiss, M.M.

    1983-01-01

    This work attempts to account for the multiplicity of tree crown forms in terms of a biological cost-benefit model in which cost is accounted for in terms of the mass of the wood of the tree and benefit is derived from the crown's efficiency as a solar collector. Methods are developed to describe complex crown shapes, to describe important aspects of complex branching systems, and to describe the three-dimensional distribution of light in forest and open habitats. Data on branching-system geometry was taken from felled trees, and data on overall crown form was taken from photographs of open-grown trees along a latitudinal transect. Computer programs were developed that can iteratively simulate tree growth based on any set of environmental and species-specific parameters. The results of simulations may be produced in printed and graphical form in ways that enable comparison to observed tree crowns. Observed north-south clines in crown form for Juniperus and Pinus are analyzed in terms of the model, and various insights into crown geometry, tree ecology, and tree physiology are won. The cost-benefit model is a powerful tool for understanding crown form and has great potential for future research.

  17. Research Report Trees, people and the built

    E-print Network

    the ecosystem services of Torbay's trees: the Torbay i-Tree Eco pilot project 18 Kenton Rogers, David Hansford planting and establishment Results of a long-term project using controlled mycorrhization with specific, Mariella Marzano, Darren Moseley, Amy Stewart and Anna Lawrence Promoting wellbeing through environment

  18. A SELECTION THEOREM IN METRIC TREES

    Microsoft Academic Search

    A. G. AKSOY; M. A. KHAMSI

    In this paper, we show that nonempty closed convex subsets of a metric tree enjoy many properties shared by convex subsets of Hilbert spaces and admissible subsets of hyperconvex spaces. Furthermore, we prove that a set-valued mapping T ? of a metric tree M with convex values has a selection T : M ? M for which d(T (x) ,T

  19. On Finding Minimum-Diameter Clique Trees

    Microsoft Academic Search

    Jean R. S. Blair; Barry W. Peyton

    1994-01-01

    A clique-tree representation of a chordal graph often reduces the size of the data structure needed to store the graph, permitting the use of extremely ecien t algorithms that take advantage of the compactness of the representation. Since some chordal graphs have many distinct clique-tree representations, it is in- teresting to consider which one is most desirable under various circumstances.

  20. Learning Decision Trees over Erasing Pattern Languages

    NASA Astrophysics Data System (ADS)

    Mukouchi, Yasuhito; Sato, Masako

    2008-07-01

    In this paper, we consider a learning problem of decision trees over erasing patterns from positive examples in the framework of identification in the limit due to Gold and Angluin. An erasing pattern is a string pattern with constant symbols and erasable variables. A decision tree over erasing patterns can be applied to identify or express transmembrane domains of amino acid sequences, and gives intuitive knowledge expressions. We first show that the ordinary decision trees with height 1 over erasing regular patterns are learnable but those with height at most 2 are not learnable from positive examples. Then we introduce a co-pattern pc for an erasing pattern p, and we redefine the language of a decision tree over erasing patterns as a language obtainable by finitely many applications of union operations and intersection operations to the languages of erasing patterns and co-patterns. Under the new definition of decision trees, we show that these decision trees with height at most n are learnable from positive examples. Moreover, we investigate efficient learning algorithms for decision trees with height 1. Terada et al. discussed the same problem for decision trees over nonerasing patterns, and the results obtained in the present work are natural extensions of Terada's results.

  1. Percolation on general trees and HIV modeling

    NASA Astrophysics Data System (ADS)

    Ahmed, E.; Agiza, H. N.

    1996-12-01

    Percolation on a general tree is studied. A general tree is used to model the transition from HIV infection into AIDS and to explain the large differences of the transition time from one patient to another. HIV has some autoimmune effects due to its low antigenic mutants. Fuzzy mathematics is used to explain these effects.

  2. Learning decision trees using the Fourier spectrum

    Microsoft Academic Search

    Eyal Kushilevitz; Yishay Mansourt

    1991-01-01

    This work gives a polynomial time algorithm for learning decision trees with respectto the uniform distribution. (This algorithm uses membership queries.) The decision treemodel that is considered is an extension of the traditional boolean decision tree model thatallows linear operations in each node (i.e., summation of a subset of the input variablesover GF (2)).This paper shows how to learn in

  3. Applications of Path Compression on Balanced Trees

    Microsoft Academic Search

    Robert Endre Tarjan

    1979-01-01

    Several fast algorithms are presented for computing functions defined on paths in trees under various assumpuons. The algorithms are based on tree mampulatton methods first used to efficiently represent equivalence relations. The algorithms have O((m + n)a(m + n, n)) running tunes, where m and n are measures of the problem size and a Is a functional reverse of Ackermann's

  4. Breeding rootstocks for tree fruit crops

    Microsoft Academic Search

    James N. Cummins; Herb S. Aldwinckle

    1995-01-01

    Identification of problems and prioritising breeding objectives based on those problems are essential first steps in a rootstock improvement program. For all tree fruits, incorporating resistances to critical diseases and pests will facilitate fruit production in a social environment demanding reduction in pesticide usage. Diseases caused by various Phytophthora species are important and can be catastrophic for all major tree

  5. TREE CROWN EXTRACTION USING MARKED POINT PROCESSES

    Microsoft Academic Search

    Guillaume Perrin; Xavier Descombes; Josiane Zerubia

    In this paper we aim at extracting tree crowns from remotely sensed images. Our approach is to consider that these im- ages are some realizations of a marked point process. The rst step is to dene the geometrical objects that design the trees, and the density of the process. Then, we use a Reversible Jump MCMC1 dynamics and a simulated

  6. Dynamic Fault Tolerance in Fat Trees

    Microsoft Academic Search

    Frank Olaf Sem-Jacobsen; Tor Skeie; Olav Lysne; José Duato

    2011-01-01

    Fat trees are a very common communication architecture in current large-scale parallel computers. The probability of failure in these systems increases with the number of components. We present a routing method for deterministically and adaptively routed fat trees, applicable to both distributed and source routing, that is able to handle several concurrent faults and that transparently returns to the original

  7. REPRESENTING RECTILINEAR STEINER TREES IN GENETIC ALGORITHMS

    E-print Network

    Julstrom, Bryant A.

    of Computer Science St. Cloud State University 720 Fourth Avenue South St. Cloud, MN 56301 julstrom and with popula- tions seeded with a single chromosome that represented a short rectilinear Steiner tree. The algorithm identi- #12;ed much shorter trees using the weighted coding, and seeding the population improved

  8. Intraspecific gene genealogies: trees grafting into networks

    Microsoft Academic Search

    David Posada; Keith A. Crandall

    2001-01-01

    Intraspecific gene evolution cannot always be represented by a bifurcating tree. Rather, population genealogies are often multifurcated, descendant genes coexist with persistent ancestors and recombination events produce reticulate relationships. Whereas traditional phylogenetic methods assume bifurcating trees, several networking approaches have recently been developed to estimate intraspecific genealogies that take into account these population-level phenomena.

  9. THE BIOTECHNOLOGY OF URBAN TREES1

    Microsoft Academic Search

    Brent H. McCown

    Trees are some of the most difficult plants to manipulate in breeding and improvement programs. Plant biotechnology offers a unique set of tools that allows the plant breeder heretofore unprecedented ability to precisely change and clone such woody perennials. Although the future of biotechnology of trees is revolutionary, there are some major problems that must be solved before the full

  10. ROOT AND BUTT ROTS OF FOREST TREES

    E-print Network

    California at Berkeley, University of

    ROOT AND BUTT ROTS OF FOREST TREES 12th International Conference on Root and Butt Rots IUFRO Medford, Oregon (USA) CONFERENCEPROCEEDINGS #12;ROOT AND BUTT ROTS OF FOREST TREES 12th International Conference on Root and Butt Rots IUFRO Working Party 7.02.01 CONFERENCE PROCEEDINGS M. Garbelotto & P

  11. Apiculture and forestry (bees and trees)

    Microsoft Academic Search

    D. B. Hill; T. C. Webster

    1995-01-01

    Honey bees are found associated with forests globally. Flowers of forest trees provide subsistence for honey bees and the trees physically provide shelter for a swarm or bee hive. Forest management and beekeeping have each had a long history both in the United States and globally, but have seldom been integrated or studied in a systematic fashion. Purposeful plantings of

  12. Reliability evaluation based on fuzzy fault tree

    Microsoft Academic Search

    Guo-zhu MAOI; Jia-wei Tu; Hui-bin Du

    2010-01-01

    In conventional fault tree analysis (FTA), some complex and uncertain events such as human errors cannot be handled effectively. Fuzzy fault tree analysis (fuzzy FTA) integrating fuzzy set evaluation and probabilistic estimation is proposed to evaluate vague events. The reliability of water supply subsystem in fire protection systems is analyzed using the proposed approach and the results prove the validity

  13. Hardwood Tree Improvement and Regeneration Center

    E-print Network

    of tree planting projects. The focus is on trees planted for timber production, although other purposes not be returned by the sale of timber products for decades. In many cases the cost is borne by one generation Forest Service Department of Forestry and Natural Resources Purdue University Financial and Tax Aspects

  14. Signature Tree Generation for Polymorphic Worms

    E-print Network

    Xiao, Bin

    Signature Tree Generation for Polymorphic Worms Yong Tang, Bin Xiao, Member, IEEE, and Xicheng Lu generate accurate signatures for worms, especially polymorphic worms. In this paper, we propose a new NSG system--PolyTree, to defend against polymorphic worms. We observe that signatures from worms

  15. The Relationship Between Trees and Human Health

    E-print Network

    Liebhold, Andrew

    The Relationship Between Trees and Human Health Evidence from the Spread of the Emerald Ash Borer--the loss of 100 million trees to the emerald ash borer, an invasive forest pest--has influenced mortality were used to estimate the relationship between emerald ash borer presence and county-level mortality

  16. Fault tree analysis for maintenance needs

    Microsoft Academic Search

    Jari Halme; Antti Aikala

    2012-01-01

    One of the key issues in maintenance is to allocate focus and resources to those components and subsystems which are the most unreliable and prone to failures. In industrial systems, fault tree analysis technique can be used to study the reliability of the complex systems and their substructures. In this paper a fault tree application for analyzing online the current

  17. How Trees Help the Power Company!

    ERIC Educational Resources Information Center

    King, Rik

    1992-01-01

    Proposes the utilization of graph theory to solve optimization problems. Defines the notion of spanning trees and presents two algorithms to determine optimization of a spanning tree. Discusses an example to connect towns by power transmission lines at minimum cost. (MDH)

  18. Decomposition Methods for Fault Tree Analysis

    Microsoft Academic Search

    Arnon Rosenthal

    1980-01-01

    Some kinds of fault tree analysis are described for which cut set enumeration is inadequate. Modularization leads to more efficient computer programs, and also identifies subsystems which are intuitively meaningful. The problem of finding all modules of a fault tree is formulated as as extension of the problem of finding all ``cut-points'' of an undirected graph. The major result is

  19. Algorithms for Haptic Rendering of CSG Trees

    Microsoft Academic Search

    Chris Raymaekers; Frank Van Reeth

    We present an algorithm for haptic rendering of CSG models. This algorithm makes use of the normalised and pruned CSG tree as needed by the graphics algorithm, thus not requiring an extra evaluation of the CSG tree. The al- gorithm also uses a generic implementation of the intersec- tion, subtraction and union operators which do not make any assumptions on

  20. Approximating Value Trees in Structured Dynamic Programming

    Microsoft Academic Search

    Craig Boutilier; Richard Dearden

    1996-01-01

    We propose and examine a method of approximate dynamic programming for Markov decision processes based on structured problem representations. We as- sume an MDP is represented using a dynamic Bayesian network, and construct value functions using decision trees as our function representation. The size of the representation is kept within acceptable limits by prun- ing these value trees so that

  1. On-Line Construction of Suffix Trees

    Microsoft Academic Search

    Esko Ukkonen

    1995-01-01

    Abstract: An on-line algorithm is presented for constructing the suffix tree for a given string in time linear in the length of the string. The new algorithm has the desirable property of processing the string symbol by symbol from left to right. It has always the suffix tree for the scanned part of the string ready. The method is developed

  2. A Dichromatic Framework for Balanced Trees

    Microsoft Academic Search

    Leonidas J. Guibas; Robert Sedgewick

    1978-01-01

    In this paper we present a uniform framework for the implementation and study of balanced tree algorithms. We show how to imbed in this framework the best known balanced tree techniques and then use the framework to develop new algorithms which perform the update and rebalancing in one pass, on the way down towards a leaf. We conclude with a

  3. A Contour Method on Cayley tree

    E-print Network

    U. A. Rozikov

    2006-11-15

    We consider a finite range lattice models on Cayley tree with two basic properties: the existence of only a finite number of ground states and with Peierls type condition. We define notion of a contour for the model on the Cayley tree. By a contour argument we show the existence of $s$ different (where $s$ is the number of ground states) Gibbs measures.

  4. On the Area of Binary Tree Layouts

    Microsoft Academic Search

    Richard P. Brent; H. T. Kung

    1980-01-01

    Abstract The binary tree is an important interconnection pattern for VLSI chip layouts. Suppose that the nodes are separated by at least unit distance and that a wire has unit width. The usual layout of a complete binary tree with n leaves takes chip area,( nlogn), but it can be arranged that all the leaves are on the boundary of

  5. Alcohol co-production from tree crops

    SciTech Connect

    Seibert, M.; Folger, G.; Milne, T.

    1982-06-01

    A concept for the sustainable production of alcohol from fermentable substrates produced on an annual basis by the reproductive organs (pods, fruits, nuts, berries, etc.) of tree crops is presented. The advantages of tree-crop systems include suitability for use on marginal land, potential productivity equivalent to row crops, minimal maintenance and energy-input requirements, environmental compatibility, and the possibility of co-product production. Honeylocust, mesquite, and persimmon are examined as potential US tree-crop species. Other species not previously considered, including osage orange and breadfruit, are suggested as tree-crop candidates for North America and the tropical developing world, respectively. Fermentation of tree-crop organs and the economics of tree-crop systems are also discussed. Currently the greatest area of uncertainty lies in actual pod or fruit yields one can expect from large tree farms under real life conditions. However, ballpark ethanol yield estimates of from 880 to 3470 l hectare/sup -1/ (94 to 400 gal acre/sup -1/) justify further consideration of tree crop systems.

  6. KDD on IVR Navigation Trees: Case Study

    Microsoft Academic Search

    Thiago T. Angelico; Thais Santos Bueno; Silvio Bortoleto; Anderson Ravanello

    2008-01-01

    This article presents a case study about data mining applied in IVR's navigation trees. Using data from a call center, the main objective is to discover patterns with information about the phone calls. Using a specific part from this information, it shows an analysis about the navigation tree of the offered service. With the WEKA, a data mining toolkit, which

  7. Making B+Trees Cache Conscious in Main Memory

    Microsoft Academic Search

    Jun Rao; Kenneth A. Ross

    2000-01-01

    Previous research has shown that cache behavior is im- portant for main memory index structures. Cache con- scious index structures such as Cache Sensitive Search Trees (CSS-Trees) perform lookups much faster than binary search and T-Trees. However, CSS-Trees are designed for decision support workloads with relatively static data. Although B+-Trees are more cache con- scious than binary search and T-Trees,

  8. Accumulation of PCB Congeners in Nestling Tree Swallows

    E-print Network

    McCarty, John P.

    Accumulation of PCB Congeners in Nestling Tree Swallows (Tachycineta bicolor) on the Hudson River Sciences, Section of Ecology and Systematics, Ithaca, New York 14850 Tree swallows (Tachycineta bicolor

  9. 469revision:1994-01-28modified:2002-07-16 Planting Kurepa Trees And Killing JechKunen Trees

    E-print Network

    Shelah, Saharon

    469revision:1994-01-28modified:2002-07-16 Planting Kurepa Trees And Killing Jech­Kunen Trees In a Model By Using One Inaccessible Cardinal 1 Saharon Shelah2 and Renling Jin Abstract By an 1­tree we mean a tree of power 1 and height 1 . Under CH and 21 > 2 we call an 1­tree a Jech­Kunen tree if it has many

  10. Fault trees and imperfect coverage

    NASA Technical Reports Server (NTRS)

    Dugan, Joanne B.

    1989-01-01

    A new algorithm is presented for solving the fault tree. The algorithm includes the dynamic behavior of the fault/error handling model but obviates the need for the Markov chain solution. As the state space is expanded in a breadth-first search (the same is done in the conversion to a Markov chain), the state's contribution to each future state is calculated exactly. A dynamic state truncation technique is also presented; it produces bounds on the unreliability of the system by considering only part of the state space. Since the model is solved as the state space is generated, the process can be stopped as soon as the desired accuracy is reached.

  11. Robins gather in a tree

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In a wooded area of Kennedy Space Center, robins gather on a tree branch just beginning to show new Spring growth. A member of the thrush family, robins inhabit towns, gardens, open woodlands and agricultural lands. They range through most of North America, spending winters in large roosts mostly in the United States but also Newfoundland, southern Ontario and British Columbia. The Center shares a boundary with the Merritt Island National Wildlife Refuge, a haven and habitat for more than 331 species of birds. The Refuge encompasses 92,000 acres that are also a habitat for 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  12. Structure theorems for game trees.

    PubMed

    Govindan, Srihari; Wilson, Robert

    2002-06-25

    Kohlberg and Mertens [Kohlberg, E. & Mertens, J. (1986) Econometrica 54, 1003-1039] proved that the graph of the Nash equilibrium correspondence is homeomorphic to its domain when the domain is the space of payoffs in normal-form games. A counterexample disproves the analog for the equilibrium outcome correspondence over the space of payoffs in extensive-form games, but we prove an analog when the space of behavior strategies is perturbed so that every path in the game tree has nonzero probability. Without such perturbations, the graph is the closure of the union of a finite collection of its subsets, each diffeomorphic to a corresponding path-connected open subset of the space of payoffs. As an application, we construct an algorithm for computing equilibria of an extensive-form game with a perturbed strategy space, and thus approximate equilibria of the unperturbed game. PMID:12060702

  13. Decision Tree for Optimization Software

    NSDL National Science Digital Library

    H.D. Mittelmann from the Department of Math and Statistics at Arizona State University and P. Spellucci from Department of Mathematics at Technical University Darmstadt have posted this guide entitled, Decision Tree for Optimization Software. The guide "aims at helping you identify ready to use solutions for your optimization problem, or at least to find some way to build such a solution using work done by others." The online document is organized into sections covering specific software problems, a collection of test results and performance tests, and example files to use with existing software. The authors also list information on available books and tutorials, some of which are online, as well as various software tools to assist in formulating an optimization problem or simplifying its solution. Those tools listed in the Web-submission section are available to try directly via the Internet.

  14. Urban Tree Effects on Soil Organic Carbon

    PubMed Central

    Edmondson, Jill L.; O'Sullivan, Odhran S.; Inger, Richard; Potter, Jonathan; McHugh, Nicola; Gaston, Kevin J.; Leake, Jonathan R.

    2014-01-01

    Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ?75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC) and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth) compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C?N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered. PMID:25003872

  15. A biophysical analysis of latitudinal tree line

    NASA Astrophysics Data System (ADS)

    Goetz, S. J.; Loranty, M. M.; Berner, L.; Jin, Y.; Randerson, J. T.

    2011-12-01

    Northern latitudinal tree line represents the interface between boreal forests and tundra ecosystems, and is the ecophysiological limit of tree recruitment and persistence. The transition between tundra and forest is typically gradual, occurring over tens to hundreds of kilometers. This gradient represents a substantial change in the biophysical properties of the earth surface, one that is particularly important in ecosystems that are snow covered for much of the year. Tree line is, however, commonly delineated by the point of the northern most tree, with no gradient between forested and non-forested ecosystems. As a consequence crisp delineations of tree line incorporated into models introduce error in surface radiation budgets due to inaccurate albedo representations. Errors in modeled carbon and water fluxes are likely as well. Here we use satellite observations to quantify several key biophysical properties across latitudinal tree line for a series of sites throughout the pan-boreal region We find decreases in NDVI and increases in albedo across the transition from boreal forest to tundra, as expected. However, in the absence of topographical barriers we find that these transitions can occur over upwards of 100 km, and that biophysical properties characteristic of tundra ecosystems can occur as far as 100 km south of tree line. This suggests that land surface models likely overestimate surface radiation budgets and carbon fluxes in the boreal biome. We discuss our results in the context of land surface models, noting specific examples from archived model runs.

  16. Exploiting graph properties of game trees

    SciTech Connect

    Plaat, A.; Pijls, W.; Bruin, A. de [Erasmus Univ., Rotterdam (Netherlands); Schaeffer, J. [Univ. of Alberta, Edmonton, AB (Canada)

    1996-12-31

    The state space of most adversary games is a directed graph. However, due to the success of simple recursive algorithms based on alpha-beta, theoreticians and practitioners have concentrated on the traversal of trees, giving the field the name {open_quotes}game-tree search,{close_quotes} This paper shows that the focus on trees has obscured some important properties of the underlying graphs. One of the hallmarks of the field of game-tree search has been the notion of the minimal tree, the smallest tree that has to be searched by any algorithm to find the minimax value. In fact, for most games it is a directed graph. As demonstrated in chess and checkers, we show that the minimal graph is significantly smaller than previously thought, proving that there is more room for improvement of current algorithms. We exploit the graph properties of the search space to reduce the size of trees built in practice by at least 25%. For over a decade, fixed-depth alpha-beta searching has been considered a closed subject, with research moving on to more application-dependent techniques. This work opens up new avenues of research for further application-independent improvements.

  17. The decision tree approach to classification

    NASA Technical Reports Server (NTRS)

    Wu, C.; Landgrebe, D. A.; Swain, P. H.

    1975-01-01

    A class of multistage decision tree classifiers is proposed and studied relative to the classification of multispectral remotely sensed data. The decision tree classifiers are shown to have the potential for improving both the classification accuracy and the computation efficiency. Dimensionality in pattern recognition is discussed and two theorems on the lower bound of logic computation for multiclass classification are derived. The automatic or optimization approach is emphasized. Experimental results on real data are reported, which clearly demonstrate the usefulness of decision tree classifiers.

  18. Tree Death Study's Climate Change Connections

    ScienceCinema

    McDowell, Nate

    2014-06-25

    What are the exact physiological mechanisms that lead to tree death during prolonged drought and rising temperatures? These are the questions that scientists are trying to answer at a Los Alamos National Laboratory research project called SUMO. SUMO stands for SUrvival/MOrtality study; it's a plot of land on the Lab's southern border that features 18 climate controlled tree study chambers and a large drought structure that limits rain and snowfall. Scientists are taking a wide variety of measurements over a long period of time to determine what happens during drought and warming, and what the connections and feedback loops might be between tree death and climate change.

  19. Algorithms for optimal dyadic decision trees

    SciTech Connect

    Hush, Don [Los Alamos National Laboratory; Porter, Reid [Los Alamos National Laboratory

    2009-01-01

    A new algorithm for constructing optimal dyadic decision trees was recently introduced, analyzed, and shown to be very effective for low dimensional data sets. This paper enhances and extends this algorithm by: introducing an adaptive grid search for the regularization parameter that guarantees optimal solutions for all relevant trees sizes, revising the core tree-building algorithm so that its run time is substantially smaller for most regularization parameter values on the grid, and incorporating new data structures and data pre-processing steps that provide significant run time enhancement in practice.

  20. Chlorinated ethenes from groundwater in tree trunks

    USGS Publications Warehouse

    Vroblesky, D.A.; Nietch, C.T.; Morris, J.T.

    1999-01-01

    The purpose of this investigation was to determine whether tree-core analysis could be used to delineate shallow groundwater contamination by chlorinated ethenes. Analysis of tree- Cores from bald cypress [Taxodium distichum (L.) Rich], tupelo (Nyssa aquatica L.), sweet gum (Liquidambar stryaciflua L.), oak (Quercus spp.), sycamore (Platanus occidentalis L.), and Ioblolly pine (Pinus taeda L.) growing over shallow groundwater contaminated with cis-1,2-dichloroethene (cDCE) and trichloroethene (TCE) showed that those compounds also were present in the trees. The cores were collected and analyzed by headspace gas chromatography. Bald cypress, tupelo, and loblolly pine contained the highest concentrations of TCE, with lesser amounts in nearby oak and sweet gum. The concentrations of cDCE and TCE in various trees appeared to reflect the configuration of the chlorinated-solvent groundwater contamination plume. Bald cypress cores collected along 18.6-m vertical transects of the same trunks showed that TCE concentrations decline by 30- 70% with trunk height. The ability of the tested trees to take up cDCE and TCE make tree coring a potentially cost-effective and simple approach to optimizing well placement at this site.The purpose of this investigation was to determine whether tree-core analysis could be used to delineate shallow groundwater contamination by chlorinated ethenes. Analysis of tree cores from bald cypress [Taxodium distichum (L.) Rich], tupelo (Nyssa aquatica L.), sweet gum (Liquidambar stryaciflua L.), oak (Quercus spp.), sycamore (Platanus occidentalis L.), and loblolly pine (Pinus taeda L.) growing over shallow groundwater contaminated with cis-1,2-dichloroethene (cDCE) and trichloroethene (TCE) showed that those compounds also were present in the trees. The cores were collected and analyzed by headspace gas chromatography. Bald cypress, tupelo, and loblolly pine contained the highest concentrations of TCE, with lesser amounts in nearby oak and sweet gum. The concentrations of cDCE and TCE in various trees appeared to reflect the configuration of the chlorinated-solvent groundwater contamination plume. Bald cypress cores collected along 18.6-m vertical transects of the same trunks showed that TCE concentrations decline by 30-70% with trunk height. The ability of the tested trees to take up cDCE and TCE make tree coring a potentially cost-effective and simple approach to optimizing well placement at this site.

  1. Tree Death Study's Climate Change Connections

    SciTech Connect

    McDowell, Nate

    2012-09-10

    What are the exact physiological mechanisms that lead to tree death during prolonged drought and rising temperatures? These are the questions that scientists are trying to answer at a Los Alamos National Laboratory research project called SUMO. SUMO stands for SUrvival/MOrtality study; it's a plot of land on the Lab's southern border that features 18 climate controlled tree study chambers and a large drought structure that limits rain and snowfall. Scientists are taking a wide variety of measurements over a long period of time to determine what happens during drought and warming, and what the connections and feedback loops might be between tree death and climate change.

  2. Regenerative tree growth: binary self-similar continuum random trees and Poisson-Dirichlet compositions

    E-print Network

    Pitman, Jim

    2008-01-01

    We use a natural ordered extension of the Chinese Restaurant Process to grow a two-parameter family of binary self-similar continuum fragmentation trees. We provide an explicit embedding of Ford's sequence of alpha model trees in the continuum tree which we identified in a previous article as a distributional scaling limit of Ford's trees. In general, the Markov branching trees induced by the two-parameter growth rule are not sampling consistent, so the existence of compact limiting trees cannot be deduced from previous work on the sampling consistent case. We develop here a new approach to establish such limits, based on regenerative interval partitions and the urn-model description of sampling from Dirichlet random distributions.

  3. TreePlus: Interactive Exploration of Networks with Enhanced Tree Layouts

    Microsoft Academic Search

    Bongshin Lee; Cynthia Sims Parr; Catherine Plaisant; Benjamin B. Bederson; Vladislav Daniel Veksler; Wayne D. Gray; Christopher Kotfila

    2006-01-01

    Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food webs, ontologies, and social networks difficult to understand and interact with. We propose a new interactive Visual Analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while

  4. The upscaling of transpiration from individual trees to areal transpiration in tree belts

    Microsoft Academic Search

    Russell S. Crosbie; Brett Wilson; Justin D. Hughes; Christopher McCulloch

    2007-01-01

    Sap flow measurements have long been used to measure transpiration in individual trees and there exist some well established\\u000a methods for upscaling individual tree volumetric transpiration to areal transpiration in plantation and forest plots. However,\\u000a where edge effects are significant, such as in tree belts, the area the volumetric transpiration is to be projected upon is\\u000a unknown. This paper provides

  5. Comparison of tree architecture using tree edit distances: application to 2-year-old apple hybrids

    Microsoft Academic Search

    Vincent Segura; Aïda Ouangraoua; Pascal Ferraro; Evelyne Costes

    2008-01-01

    In fruit trees, understanding genetic determinisms of architectural traits is considered as a promising manner to control\\u000a vegetative development and yield regularity. In this context, our study aimed to classify 2-year-old apple hybrids on the\\u000a basis of their architectural traits. From a fine phenotyping, trees were described as tree graphs, including topological and\\u000a geometric information. To evaluate the similarity between

  6. A Spring Playscape Project: Building a Tree Circle

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2009-01-01

    The Tree Circle is a green gathering area for children made by planting trees in a circle. For children, the Tree Circle becomes a magical place for dramatic play, quiet retreat, or lively nature exploration. For teachers and parents it becomes a shady grove for snacks and stories. The trees create a sweet spot that changes during the seasons and…

  7. "Flowering Dogwood New Hampshire's Big Tree for May"

    E-print Network

    New Hampshire, University of

    simplicity of the clear white flowers of native dogwood trees (Cornus floridia) that grow along forest edges of the blossoms on boughs laden with flowers. Most yards had both pink and white trees creating a beautiful"Flowering Dogwood New Hampshire's Big Tree for May" By Anne Krantz, NH Big Tree Team The elegant

  8. Optimal Pruning for Tree-Structured Vector Quantization.

    ERIC Educational Resources Information Center

    Lin, Jianhua; And Others

    1992-01-01

    Analyzes the computational complexity of optimal binary tree pruning for tree-structured vector quantization. Topics discussed include the combinatorial nature of the optimization problem; the complexity of optimal tree pruning; and finding a minimal size pruned tree. (11 references) (LRW)

  9. Tree filtering for high density airborne LiDAR data

    Microsoft Academic Search

    M. Z. Abd Rahman; B. G. H. Gorte

    2008-01-01

    A high resolution Airborne LiDAR data creates better opportunity for an individual tree measurement and provides valuable results for more precise forest inventory. This paper presents tree filtering approach that able to separate dominant tree and undergrowth vegetation. The results can be used for a detailed individual tree measurement. This process is one of the main steps for a single

  10. Set operations on polyhedra using binary space partitioning trees

    Microsoft Academic Search

    William C. Thibault; Bruce F. Naylor

    1987-01-01

    We introduce a new representation for polyhedra by showing how Binary Space Partitioning Trees (BSP trees) can be used to represent regular sets. We then show how they may be used in evaluating set operations on polyhedra. The BSP tree is a binary tree representing a recursive partitioning of d-space by (sub-)hyperplanes, for any dimension d. Their previous application to

  11. Dig up Trees in Literature. In the Library.

    ERIC Educational Resources Information Center

    Hurst, Carol Otis

    1997-01-01

    Describes ideas that can help teachers organize activities around the subject of trees. The ideas include searching books and Internet sites for pictures and drawings of trees, creating stories with trees, planning field trips, inviting experts to share their knowledge and skills, exploring current events related to trees, and finally, creating…

  12. Phenomena and mechanism of electrical tree in silicone rubber

    Microsoft Academic Search

    B. X. Du; Z. L. Ma; Y. Gao

    2009-01-01

    In this paper, room temperature vulcanized (RTV) silicone rubber (SiR) was employed as test sample to investigate the tree aging phenomena and mechanism of silicone rubber under commercial voltage. The structures and growth characteristics of electrical tree in SiR were observed by using a digital camera. A new parameter, the treeing proportion is introduced to describe the electrical tree propagation

  13. The Hydraulic System of Trees: Theoretical Framework and Numerical Simulation

    Microsoft Academic Search

    THOMAS FRÜH; WINFRIED KURTH

    1999-01-01

    Empirical studies pose the problem of the physiological integration of the tree organism, which is also important on the scale of ecosystems. Recently, spatially distributed models emerged, which approach this problem by reflecting the close linkage between physiological processes and the structures of trees and tree stands. In the case of water flow, the tree organism can be regarded as

  14. Configuration of ACK Trees for Multicast Transport Protocols

    Microsoft Academic Search

    Seok Joo Koh Koh; Eunsook Kim Kim; Juyoung Park Park; Shin Gak Kang Kang; Ki Shik Park Park; Chee Hang Park Park

    2001-01-01

    For scalable multicast transport, one of the promising approaches is to employ a control tree known as acknowl- edgement (ACK) tree which can be used to convey infor- mation on reliability and session status from receivers to a root sender. The existing tree configuration has focused on a 'bottom-up' scheme in which ACK trees grow from leaf receivers toward a

  15. Stochastic Search Strategy for Estimation of Maximum Likelihood Phylogenetic Trees

    Microsoft Academic Search

    Laura A. Salter; Dennis K. Pearl

    2001-01-01

    The maximum likelihood (ML) method of phylogenetic tree construction is not as widely used as other tree construction methods (e.g., parsimony, neighbor-joining) because of the prohibitive amount of time required to énd the ML tree when the number of sequences under consideration is large. To overcome this diféculty, we propose a stochastic search strategy for estimation of the ML tree

  16. A Support Vector Machine Approach to Decision Trees

    E-print Network

    Varela, Carlos

    A Support Vector Machine Approach to Decision Trees K. P. Bennett Mathematical Sciences Department theory and support vector ma­ chines are generalized to decision trees. A support vector machine is used for each decision in the tree. The ``optimal'' decision tree is characterized, and both a primal and dual

  17. Tree-width and functional dependencies in Isolde Adler

    E-print Network

    Adler, Isolde

    Tree-width and functional dependencies in databases Isolde Adler Humboldt University Berlin PODS'08 functions for tree decompositions 4. Tractable restrictions of HOM 5. Conclusion ISOLDE ADLER TREE ADLER TREE-WIDTH AND FUNCTIONAL DEPENDENCIES IN DATABASES 3/38 #12;Boolean conjunctive queries BCQ

  18. A constrained edit distance algorithm between semi-ordered trees

    Microsoft Academic Search

    Aïda Ouangraoua; Pascal Ferraro

    2009-01-01

    In this paper, we propose a formal definition of a new class of trees called semi-ordered trees and a polynomial dynamic programming algorithm to compute a constrained edit distance between such trees. The core of the method relies on a similar approach to compare unordered [Kaizhong Zhang, A constrained edit distance between unordered labeled trees, Algorithmica 15 (1996) 205–222] and

  19. The Average Height of Catalan Trees by Counting Lattice Paths

    E-print Network

    Dershowitz, Nachum

    The Average Height of Catalan Trees by Counting Lattice Paths Nachum Dershowitz Christian to a leaf. The height of a tree is the number of nodes on a maximal path from 1 #12;email from Me subject as a Catalan tree Figure 2: Catalan tree of height 5 and size 13. root to leaf; for example, travel down

  20. Enumerative sequences of leaves and nodes in rational trees

    E-print Network

    Boyer, Edmond

    of leaves or nodes in a rational tree. Let s be an IN-rational sequence of nonnegative numbers, that is a se in "Theoretical Computer Science 221, 1-2 (1999) 41-60" #12;A rational tree is a tree which has only a nite numberEnumerative sequences of leaves and nodes in rational trees Frederique Bassino Institut Gaspard

  1. Methodology for Computer-Aided Fault Tree Analysis

    Microsoft Academic Search

    R. Ferdous; F. I. Khan; B. Veitch; P. R. Amyotte

    2007-01-01

    Fault tree analysis is a systematic, deductive and probabilistic risk assessment tool which elucidates the causal relations leading to a given undesired event. Quantitative fault tree (failure) analysis requires a fault tree and failure data of basic events. Development of a fault tree and subsequent analysis require a great deal of expertise, which may not be available all the time.

  2. Spanning Trees of Bounded Degree Graphs John Michael Robson 1

    E-print Network

    Recanati, Catherine

    Spanning Trees of Bounded Degree Graphs John Michael Robson 1 LaBRI, Universit#19;e Bordeaux 1 351 cours de la Lib#19;eration, 33405 Talence Cedex, France robson@labri.fr Abstract. We consider lower graph G. #12; 2 Robson Clearly a tree has only one spanning tree and adding a single edge to a tree

  3. Page 1 of 8 Generation of Fault Trees from Simulated

    E-print Network

    Madden, Michael

    tree analysis is widely used in industry in fault diagnosis. The diagnosis of incipient or `soft of the approach. 1 Introduction Fault tree analysis (FTA) and fault tree synthesis (FTS) evolved primarily within for over 30 years. Fault tree analysis can be valuable as a design tool; using it to identify and eliminate

  4. A Tool for Efficient Fault Tree Analysis (extended version)

    E-print Network

    Vellekoop, Michel

    DFTCalc: A Tool for Efficient Fault Tree Analysis (extended version) Florian Arnold1 , Axel that provides (1) efficient fault tree modelling via compact representations; (2) effec- tive analysis, allowing. Fault Trees. Fault tree analysis (FTA) is a graphical technique that is often used in industry [27

  5. Penrose tiling fractality in coordination Cayley's tree graphs representation

    Microsoft Academic Search

    A. N. Mihalyuk; P. L. Titov; V. V. Yudin

    2010-01-01

    We offer the mathematical apparatus for mapping lattice and cellular systems into the generalized coordination Cayley's tree graphs. These Cayley's trees have a random branchiness property and an intralayer interbush local intersection. Classical Bethe-Cayley tree graphs don't have these properties. Bush type simplicial decomposition on Cayley's tree graphs is introduced, on which the enumerating polynomials or enumerating distributions are built.

  6. Comparative water use by dryland trees in Parklands in Senegal

    Microsoft Academic Search

    J. D. Deans; R. C. Munro

    2004-01-01

    Despite the clear evidence of competition for water between trees and crops, there have been very few studies comparing simultaneous water use by differing tree species in drylands. Comparative water use by dryland trees was measured in Senegal using heat balance gauges at the end of the wet season and in the dry season. Significant differences between tree species were

  7. In this issue: Forest Stewardship and Tree Farm Team Up

    E-print Network

    Watson, Craig A.

    In this issue: Forest Stewardship and Tree Farm Team Up Welcome New Steward Co-editors What Stewardship and Tree Farm Programs Team Up in 2008 By Chris Demers, UF Forest Stewardship Coordinator For Tree. This is the inaugural issue of a partnership between Floridas Forest Stewardship and Tree Farm Programs to reach

  8. Integral trees homeomorphic to a double star A. E. Brouwer

    E-print Network

    Brouwer, Andries E.

    Integral trees homeomorphic to a double star A. E. Brouwer 2009-09-17 Abstract Trees with two of degree larger than two. They write We would now like to examine the trees homeomorphic to a double star, that is, to a tree obtained by joining the centers of two stars with an edge. Unfortunately, the details

  9. TREES AND HUMANKIND: CULTURAL AND PSYCHOLOGICAL BINDINGS I

    Microsoft Academic Search

    KIM CODER

    1996-01-01

    NO VE MB ER 1996 To effectively educate people about trees and forests, natural resource managers must understand the beliefs and perceptions concerning trees and forests within different communities and cultures. The reverence and adoration of trees has a strong psychological and social foundation in most human cul- tures. The influence of trees and forests on cultural development can better

  10. Exploiting Thread-Level Parallelism to Build Decision Trees

    E-print Network

    Minnesota, University of

    Exploiting Thread-Level Parallelism to Build Decision Trees Karsten Steinhaeuser, Nitesh V. Chawla task, and decision trees have emerged as a popular classifier due to their simplicity and rela- tively a decision tree still becomes intractable. Hence, there is an increasing need for more efficient tree

  11. Inclusion Constraints over Non-empty Sets of Trees?

    E-print Network

    Paris-Sud XI, Université de

    Inclusion Constraints over Non-empty Sets of Trees? Martin Muller1, Joachim Niehren1 and Andreas of trees. The existing systems of set constraints can express INES con- straints only if they include of trees. In this paper we focus on sets of possibly in nite trees. All given results can be easily adapted

  12. On the re-rooting invariance property of Levy trees

    E-print Network

    Le Gall, Jean-François

    On the re-rooting invariance property of L´evy trees Thomas Duquesne and Jean-Fran¸cois Le Gall of the continuous random trees called L´evy trees. This extends previous results due to several authors. 1 Introduction Continuous random trees have been studied extensively in the last fifteen years and have found

  13. Regular networks can be uniquely constructed from their trees

    E-print Network

    Willson, Stephen J.

    1 Regular networks can be uniquely constructed from their trees Stephen J. Willson Department with labelled leaves displays a tree T when there exists a way to select a unique parent of each hybrid vertex resulting in the tree T. Let Tr(N) denote the set of all trees displayed by the network N. In general

  14. Phylogenetic trees & orthology Fritz-Laylin et al. cell 2010

    E-print Network

    Utrecht, Universiteit

    3/6/2013 1 Phylogenetic trees & orthology #12;Fritz-Laylin et al. cell 2010 ·Med11 vs kinases: orthology ·Trees are useful beyond that: HGT, timing of duplication, study of all kinds of evolutionary processes #12;Gene Trees, Gene Duplications, and Orthology · How to make trees · Bootstrap · Interpreting

  15. Dynamic Trees: A Hierarchical Probabilistic Approach to Image Modelling 

    E-print Network

    Adams, Nicholas J.

    This work introduces a new class of image model which we call dynamic trees or DTs. A dynamic tree model specifies a prior over structures of trees, each of which is a forest of one or more tree-structured belief networks ...

  16. 45TREE CARE INDUSTRY -JULY 2001 Urban Forestry

    E-print Network

    Schweik, Charles M.

    45TREE CARE INDUSTRY - JULY 2001 Urban Forestry PrioritizingRiskTrees in a Community By Brian Kane foresters are responsible for maintaining park and street trees that are safe from prob- lems that could lead to property damage or injury. The literature offers a general consensus about what makes a tree

  17. Dual-Tree Wavelets and their application to Vision Systems

    E-print Network

    Kingsbury, Nick

    Dual-Tree Wavelets and their application to Vision Systems: key-point detectors and descriptors, 21 March 2013 Nick Kingsbury (Univ. of Cambridge) Dual-Tree Wavelets & Vision UDRC 2013 (2) 1 / 30 #12;Introduction Dual-Tree Wavelets and their application to Vision Systems Properties of Dual-Tree

  18. Introduction to Artificial Intelligence Problem Space and Search Tree

    E-print Network

    Qu, Rong

    Introduction to Artificial Intelligence (G51IAI) Dr Rong Qu Problem Space and Search Tree #12;G51IAI ­ Search Space & Tree Trees Nodes Root node Children/parent of nodes Leaves Branches Average branching factor average number of branches of the nodes in the tree JB C D E F G A H I #12;G51IAI ­ Search

  19. Tree Isomorphism: An Exercise in Functional Programming Jayadev Misra

    E-print Network

    Misra, Jayadev

    Tree Isomorphism: An Exercise in Functional Programming Jayadev Misra 9/10/01 1 Problem Description The problem is to decide if two unordered trees are the same. More precisely, define a binary relation isomorphic over non-empty trees by the following rules. 1. A tree with a single node (the root) is isomorphic

  20. A tree projection algorithm for wavelet-based

    E-print Network

    Thompson, Andrew

    A tree projection algorithm for wavelet-based sparse approximation Andrew Thompson Duke University, North Carolina, USA joint with Coralia Cartis (University of Edinburgh) #12;Wavelet trees · Discrete wavelet transforms (DWTs) have an inherent tree structure #12;Wavelet trees · Discrete wavelet transforms

  1. TREE-RING STUDY OF HYDROLOGIC VARIABILITY IN THE

    E-print Network

    1 TREE-RING STUDY OF HYDROLOGIC VARIABILITY IN THE PEACE-ATHABASCA DELTA, CANADA By David M. Meko Laboratory of Tree-Ring Research University of Arizona Tucson, Arizona Report prepared for LAWSON LUNDELL collect the tree-ring samples in the field. Ramzi Touchan cross-dated the tree-ring samples and supervised

  2. BINARY TREE-STRUCTURED PARTITION AND CLASSIFICATION DAVID MCDIARMID

    E-print Network

    May, J. Peter

    BINARY TREE-STRUCTURED PARTITION AND CLASSIFICATION SCHEMES DAVID MCDIARMID Abstract. Binary tree-structured partition and classification schemes are a class of non- parametric tree-based approaches to classification problems. After developing an original definition of tree-structured partition and classification schemes

  3. Tree Automata with Global Constraints Emmanuel Filiot1

    E-print Network

    Paris-Sud XI, Université de

    Tree Automata with Global Constraints Emmanuel Filiot1 Jean-Marc Talbot2 Sophie Tison1 1 INRIA of Provence (LIF, UMR 6166 of CNRS), Marseille Abstract. A tree automaton with global tree equality and disequality constraints, TAGED for short, is an automaton on trees which allows to test (dis

  4. 32 TREE CARE INDUSTRY -OCTOBER 2001 From Attack

    E-print Network

    32 TREE CARE INDUSTRY - OCTOBER 2001 WhatKeeps TreesFree From Attack by Insects & Diseases? By Clive G. Jones T here is a tremendous diversity of insect herbivores and plant pathogens on trees, including a very large number of species that can adversely affect tree growth, survival and aesthetics

  5. Tree detection from aerial imagery Computer and Information Sciences

    E-print Network

    Giger, Christine

    Tree detection from aerial imagery Lin Yang Computer and Information Sciences University,emilp,xiaoxuma}@google.com ABSTRACT We propose an automatic approach to tree detection from aerial imagery. First a pixel-level classifier is trained to as- sign a {tree, non-tree} label to each pixel in an aerial image. The pixel

  6. On the Minimum Size of a Contraction-Universal Tree

    E-print Network

    Paris-Sud XI, Université de

    On the Minimum Size of a Contraction-Universal Tree Olivier Bodini LIP, ´Ecole Normale Sup´erieure de Lyon, 46 All´ee d'Italie, 69364 Lyon Cedex 05, France. Abstract. A tree Tuni is m-universal for the class of trees if for every tree T of size m, T can be obtained from Tuni by successive contractions

  7. TREES IN TOWNS II AND THE CONTRIBUTION OF ARBORICULTURE

    Microsoft Academic Search

    Mark Johnston

    2010-01-01

    In February 2008, the Department for Communities and Local Government published its long awaited report on urban trees in England entitled Trees in Towns II. The report assesses the urban tree population in England as well as identifying the policies and practice of urban tree management by English local authorities. This paper highlights the significance of this government report for

  8. General Information for Managing Trees Under Stress July 26, 2011

    E-print Network

    General Information for Managing Trees Under Stress July 26, 2011 Suggested Care of Trees Showing Signs of Stress: Good growing conditions and appropriate care to minimize stress will enable many trees showing signs of stress to recover and return to good health. Many trees have the capacity to recover

  9. Dealing with Storm-Damaged Trees 

    E-print Network

    Kirk, Melanie; Taylor, Eric; Foster, C. Darwin

    2005-10-25

    Many homeowners need help caring for or removing damaged trees after a natural disaster. This publication explains what a certified arborist is and how to select one. It also cautions against burning debris downed by a storm....

  10. Optimal static pricing for a tree network

    E-print Network

    Caro, Felipe

    We study the static pricing problem for a network service provider in a loss system with a tree structure. In the network, multiple classes share a common inbound link and then have dedicated outbound links. The motivation ...

  11. job," said Professor of Economics Scott Trees.

    E-print Network

    with a talk by Professor Scott Trees. One way to ensure a job after graduation is through internships. "A lot Buddies, the impact of Jack- ie's service has extended well beyond cam- pus. Building on her junior year

  12. Deforestation: Transforming programs to eliminate trees

    E-print Network

    Wadler, Philip

    Deforestation: Transforming programs to eliminate to eliminate inter* *mediate lists_and intermediate trees_called the Deforestation Algorithm. A form of fun. Treeless form and the Deforestation Algorithm are presented in three steps. * *The first step presents

  13. Communicating Phylogeny: Evolutionary Tree Diagrams in Museums

    E-print Network

    MacDonald, Teresa; Wiley, Edward O.

    2012-01-01

    Tree of life diagrams are graphic representations of phylogeny—the evolutionary history and relationships of lineages—and as such these graphics have the potential to convey key evolutionary ideas and principles to a variety of audiences. Museums...

  14. Faster generation of random spanning trees

    E-print Network

    Kelner, Jonathan Adam

    In this paper, we set forth a new algorithm for generating approximately uniformly random spanning trees in undirected graphs. We show how to sample from a distribution that is within a multiplicative (1+ d) of uniform in ...

  15. Range Searching Over Tree Cross Products

    Microsoft Academic Search

    Adam L. Buchsbaum; Michael T. Goodrich; Jeffery R. Westbrook

    2000-01-01

    We introduce the tree cross-product problem, which abstracts a data structure common to applications in graph visualization, string matching, and software analysis. We design solutions with a variety of tradeos, yielding improvements and new results for these applications.

  16. Gaussian Faithful Markov Trees Dhafer Malouche 1

    E-print Network

    Paris-Sud XI, Université de

    Gaussian Faithful Markov Trees Dhafer Malouche 1 & Bala Rajaratnam 2 1 Ecole Sup´erieure de la Statistique et de l'Analyse de l'Information. dhafer.malouche@essai.rnu.tn 2 Stanford University brajarat

  17. Small phylogeny problem: character evolution trees

    E-print Network

    Lonardi, Stefano

    /1 #12;Phylogenetics science determining ancestor/descendent relationships between species usually science determining ancestor/descendent relationships between species usually expressed by phylogenetic ancestor/descendent relationships between species usually expressed by phylogenetic trees the leaves

  18. Deforestation: Transforming programs to eliminate trees

    E-print Network

    Wadler, Philip

    , intermediate trees---are both the basis and the bane of a certain style of programming in functional languages are also the bane---they exact a cost at run time. If strict evaluation is used, the program requires space

  19. Trees and forests in British society

    E-print Network

    skills in sociology, anthropology, economics, forestry, political science and geography. Since 2000, ourTrees and forests in British society Ten years of social science Forest Research is the research

  20. Constructing event trees for volcanic crises

    USGS Publications Warehouse

    Newhall, C.; Hoblitt, R.

    2002-01-01

    Event trees are useful frameworks for discussing probabilities of possible outcomes of volcanic unrest. Each branch of the tree leads from a necessary prior event to a more specific outcome, e.g., from an eruption to a pyroclastic flow. Where volcanic processes are poorly understood, probability estimates might be purely empirical - utilizing observations of past and current activity and an assumption that the future will mimic the past or follow a present trend. If processes are better understood, probabilities might be estimated from a theoritical model, either subjectively or by numerical simulations. Use of Bayes' theorem aids in the estimation of how fresh unrest raises (or lowers) the probabilities of eruptions. Use of event trees during volcanic crises can help volcanologists to critically review their analysis of hazard, and help officials and individuals to compare volcanic risks with more familiar risks. Trees also emphasize the inherently probabilistic nature of volcano forecasts, with multiple possible outcomes.

  1. New bounds on optimal binary search trees

    E-print Network

    Harmon, Dion (Dion Kane)

    2006-01-01

    Binary search trees (BSTs) are a class of simple data structures used to store and access keys from an ordered set. They have been around for about half a century. Despite their ubiquitous use in practical programs, ...

  2. Controlling Tree Squirrels in Urban Areas 

    E-print Network

    Texas Wildlife Services

    2006-09-06

    In urban areas, tree squirrels can become pests when they eat pecans, berries, bird seed or vegetables from home gardens, or when they nest in attics. This leaflet discusses control of squirrels by fencing, trapping, poisoning and shooting....

  3. Steiner-tree confinement and tetraquarks

    E-print Network

    Jean-Marc Richard

    2009-05-14

    The linear confinement in quarkonium is generalised as a minimal tree, with interesting geometrical properties. This model binds tetraquarks more easily than the additive model used in earlier investigations.

  4. Spanning tree generating functions and Mahler measures

    E-print Network

    Anthony J. Guttmann; Mathew D. Rogers

    2012-08-26

    We define the notion of a spanning tree generating function (STGF) $\\sum a_n z^n$, which gives the spanning tree constant when evaluated at $z=1,$ and gives the lattice Green function (LGF) when differentiated. By making use of known results for logarithmic Mahler measures of certain Laurent polynomials, and proving new results, we express the STGFs as hypergeometric functions for all regular two and three dimensional lattices (and one higher-dimensional lattice). This gives closed form expressions for the spanning tree constants for all such lattices, which were previously largely unknown in all but one three-dimensional case. We show for all lattices that these can also be represented as Dirichlet $L$-series. Making the connection between spanning tree generating functions and lattice Green functions produces integral identities and hypergeometric connections, some of which appear to be new.

  5. Operated semigroups, Motzkin paths and rooted trees

    E-print Network

    Guo, Li

    2007-01-01

    Combinatorial objects such as rooted trees that carry a recursive structure have found important applications recently in both mathematics and physics. We put such structures in an algebraic framework of operated semigroups. This framework provides the concept of operated semigroups with intuitive and convenient combinatorial descriptions, and at the same time endows the familiar combinatorial objects with a precise algebraic interpretation. As an application, we obtain constructions of free Rota-Baxter algebras in terms of Motzkin paths and rooted trees.

  6. Tree graph grammars for pattern recognition

    Microsoft Academic Search

    Alberto Sanfeliu; K. S. Fu

    1982-01-01

    This paper deals with a class of grammars which is called tree-graph grammar (TGG) and its attributed version (ATGG, attributed-tree-graph grammar). The features of this class of grammars include its power to generate useful graphs and its fast parser. Principally, the graphs that can be characterized by these grammars are a subset of hierarchical graphs, including planar graphs. Also these

  7. Fescue Sod Suppresses Young Pecan Tree Growth

    Microsoft Academic Search

    Michael W. Smith; Becky S. Cheary; Becky L. Carroll

    Additional index words. Carya illinoinensis, Festuca arundinacea Abstract. Newly planted pecan (Carya illinoinensis Wangenh. C. Koch) trees were grown for 3 years in a tall fescue (Festuca arundinacea Shreb. cv. Kentucky 31) sod with vegetation-free circles 0, 0.91, 1.83, 3.66, or 7.32 m in diameter. Trees were irrigated to minimize growth differences associated with water competition from fescue. There were

  8. Improved surname pronunciations using decision trees

    Microsoft Academic Search

    Julie Ngan; Aravind Ganapathiraju; Joseph Picone

    1998-01-01

    Proper n oun p ronunciation g eneration i s a particularly c hallenging p roblem i n s peech recognition since a large percentage of proper nouns often defy typical letter-to-sound conversion rules. In this paper, we present decision tree methods which outperform neural network techniques. Using the decision tree method, we have achieved an overall error rate of 45.5%,

  9. Circuits versus Trees in Algebraic Complexity

    Microsoft Academic Search

    Pascal Koiran

    2000-01-01

    . This survey is devoted to some aspects of the \\\\P = NP ?"problem over the real numbers and more general algebraic structures.We argue that given a structure M , it is important to nd out whetherNPM problems can be solved by polynomial depth computation trees,and if so whether these trees can be eciently simulated by circuits.Point location, a problem

  10. Skin Irritancy of Tea Tree Oil

    Microsoft Academic Search

    Ian A. Southwell; Susanne Freeman; Diana Rubel

    1997-01-01

    The essential oil of Australian tea tree (Melaleuca alternifolia) has been investigated for skin irritancy using an occlusive patch test on 25 human subjects for 21 days. 1,8-Cineole, the constituent reported as being responsible for tea tree oil skin irritancy, was similarly tested. Irritancy was not detected from any of eight preparations containing pure cineole in concentrations of 0.0, 3.8,

  11. Trees and Shrubs in Northwest Texas.

    E-print Network

    Gaines, Frank; Karper, R. E. (Robert Earl); Jones, D. L. (Don L.)

    1932-01-01

    Suitable for Screens 1. Spirea (Spiraea van.houttei) 2. Salt Cedar ( Tamarix) 3. Vitex ( Vitex negundo var. incisa) 4. Chaste Tree ( Vitex agnus-castus) 5. Amur River Privet (Ligustrum, amurense) 6. Weigela ( Weigela rosea) 7. Euonymus (Euonymus... Suitable for the Following Purposes: Tall Backgrounds 1. Golden Bell (Forsythia m~spensa) 2. Staghorn Sumac (Rhus typh.ina) 3. Vitex ( Vitex ne.qun,do) 4. Chaste Tree ( Vitex agnus-castu.~) 5. Weigela ( Weigela rosea) 6. Euonymus (Euonyrnus jnponica...

  12. Tree Ferns Biotechnology: From Spores to Sporophytes

    Microsoft Academic Search

    Jan J. Rybczy?ski; Anna Miku?a

    \\u000a Tree ferns are typical for rain forest of tropical and subtropical climate and play a very crucial role in the ecology of\\u000a lands of origin and some of the ­species are economically very important due to various utilization by autochthons or citizens.\\u000a Majority of tree ferns are illegally collected from natural sites, which has resulted in the decrease of their

  13. Forest gap dynamics and tree regeneration

    Microsoft Academic Search

    Shin-Ichi Yamamoto

    2000-01-01

    When one or a few canopy trees die (or are injured) in a forest, small openings, which are called ‘gaps,’ are formed in the\\u000a forest canopy and are then filled with other trees. This sort of forest dynamics is termed gap dynamics; a large number of\\u000a papers and data on gap dynamics have been accumulated since the 1970’s, and gap

  14. Dieback of rural trees in Australia

    Microsoft Academic Search

    F. R. Wylie

    1988-01-01

    Much of Australia's woody vegetation has been cleared since European settlement, allowing extensive agricultural and pastoral\\u000a industries to develop. Although scattered stands of native trees were often left on farmland, many of these trees are now\\u000a in decline, particularly in regions where farm management is intensive. Rural dieback is a dramatic manifestation of this\\u000a decline, and is characterized by a

  15. Trusted Spanning Tree for Delay Tolerant MANETs

    Microsoft Academic Search

    A. Piyatumrong; Pascal Bouvry; Frédéric Guinand; K. Lavangnananda

    2008-01-01

    Quality of service is an important issue in Delay Tole- rant MANETs. This work aims at increasing the QoS in such networks by relying on spanning forests (DA-GRS). The existing algorithms are improved by introducing the notion of trust into the spanning forest and choosing the most robust (trustable) spanning trees among existing op- portunities. The robustness\\/quality of the tree

  16. Partitioning Nominal Attributes in Decision Trees

    Microsoft Academic Search

    Don Coppersmith; Se June Hong; Jonathan R. M. Hosking

    1999-01-01

    . To find the optimal branching of a nominal attribute at a node in anL-ary decision tree, one is often forced to searchover all possible L-ary partitionsfor the one that yields the minimum impurity measure. For binary trees (L =2)when there are just two classes a short-cut search is possible that is linear in n,thenumber of distinct values of the

  17. Deforestation: Transforming Programs to Eliminate Trees

    Microsoft Academic Search

    Philip Wadler

    1990-01-01

    An algorithm that transforms programs to eliminate intermediate trees is presented.The algorithm applies to any term containing only functions with definitionsin a given syntactic form, and is suitable for incorporation in an optimising compiler.Intermediate lists---and, more generally, intermediate trees---are both the basis andthe bane of a certain style of programming in functional languages. For example, tocompute the sum of the

  18. Screening for antimicrobial activity of ten medicinal plants used in Colombian folkloric medicine: A possible alternative in the treatment of non-nosocomial infections

    PubMed Central

    Rojas, Jhon J; Ochoa, Veronica J; Ocampo, Saul A; Muñoz, John F

    2006-01-01

    Background The antimicrobial activity and Minimal Inhibitory Concentration (MIC) of the extracts of Bidens pilosa L., Bixa orellana L., Cecropia peltata L., Cinchona officinalis L., Gliricidia sepium H.B. & K, Jacaranda mimosifolia D.Don, Justicia secunda Vahl., Piper pulchrum C.DC, P. paniculata L. and Spilanthes americana Hieron were evaluated against five bacteria (Staphylococcus aureus, Streptococcus ? hemolític, Bacillus cereus, Pseudomonas aeruginosa, and Escherichia coli), and one yeast (Candida albicans). These plants are used in Colombian folk medicine to treat infections of microbial origin. Methods Plants were collected by farmers and traditional healers. The ethanol, hexane and water extracts were obtained by standard methods. The antimicrobial activity was found by using a modified agar well diffusion method. All microorganisms were obtained from the American Type Culture Collection (ATCC). MIC was determined in the plant extracts that showed some efficacy against the tested microorganisms. Gentamycin sulfate (1.0 ?g/ml), clindamycin (0.3 ?g/ml) and nystatin (1.0 ?g/ml) were used as positive controls. Results The water extracts of Bidens pilosa L., Jacaranda mimosifolia D.Don, and Piper pulchrum C.DC showed a higher activity against Bacillus cereus and Escherichia coli than gentamycin sulfate. Similarly, the ethanol extracts of all species were active against Staphylococcus aureus except for Justicia secunda. Furthermore, Bixa orellana L, Justicia secunda Vahl. and Piper pulchrum C.DC presented the lowest MICs against Escherichia coli (0.8, 0.6 and 0.6 ?g/ml, respectively) compared to gentamycin sulfate (0.9 8g/ml). Likewise, Justicia secunda and Piper pulchrum C.DC showed an analogous MIC against Candida albicans (0.5 and 0.6 ?g/ml, respectively) compared to nystatin (0.6 ?g/ml). Bixa orellana L, exhibited a better MIC against Bacillus cereus (0.2 ?g/ml) than gentamycin sulfate (0.5 ?g/ml). Conclusion This in vitro study corroborated the antimicrobial activity of the selected plants used in folkloric medicine. All these plants were effective against three or more of the pathogenic microorganisms. However, they were ineffective against Streptococcus ? hemolytic and Pseudomonas aeruginosa. Their medicinal use in infections associated with these two species is not recommended. This study also showed that Bixa orellana L, Justicia secunda Vahl. and Piper pulchrum C.DC could be potential sources of new antimicrobial agents. PMID:16483385

  19. Clarifying the Effects of Dwarfing Rootstock on Vegetative and Reproductive Growth during Tree Development: A Study on Apple Trees

    Microsoft Academic Search

    E. Costes; E. Garcia-Villanueva

    2007-01-01

    † Background and Aims Despite the widespread use of dwarfing rootstocks in the fruit-tree industry, their impact on tree architectural development and possible role in the within-tree balance between growth and flowering are still poorly understood, in particular during the early years of growth. The present study addressed this question in apple trees, through a detailed analysis of shoot populations,

  20. Finding the tree of life: matching phylogenetic trees to the fossil record through the 20th century

    E-print Network

    Benton, Michael

    Finding the tree of life: matching phylogenetic trees to the fossil record through the 20th century.benton@bristol.ac.uk) Phylogenies, or evolutionary trees, are fundamental to biology. Systematists have laboured since the time of Darwin to discover the tree of life. Recent developments in systematics, such as cladistics and mol