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Last update: August 15, 2014.
1

DESENVOLVIMENTO SUSTENTÁVEL E SOJICULTURA EM RORAIMA: TRAJETÓRIAS ANTAGÔNICAS OU CONCILIÁVEIS?  

Microsoft Academic Search

Quando há o entendimento de que crescimento e desenvolvimento são sinônimos, tende-se a prezar uma dimensão do desenvolvimento em detrimento das outras, o que acaba por prejudicar a população por meio de carências nas condições de vida e destruição do meio ambiente principalmente. O ideal do desenvolvimento sustentável surge na tentativa de harmonizar crescimento econômico, igualdade social e preservação ambiental.

Luciana Dal Gianluppi; Paulo Dabdab Waquil

2008-01-01

2

Swine Waste Management Through Kyusei Nature Farming and EM  

Microsoft Academic Search

Ten swine farms were installed waste management systems. Farm size was different from 200 to 3,000 pigs. Pigs were managed under a fully automated system. Treatments were made with 2 x 3 Latin square arrangements. Two seasonal effects were hot summer (25 - 35 0C) and cold winter (10 - -15 0C). Three EM levels were 1:1,000, 1:5,000, 1:10,000 dilution

Sangsoo Sun; Byungjin Ahn; Kyuho Myung; Kwanghyun Kim

3

DESENVOLVIMENTO E VALIDAÇÃO DE MÉTODO ANALÍTICO PARA QUANTIFICAÇÃO DE DOXICICLINA EM PLASMA HUMANO The development and validation of an analytical method for doxycycline quantification in human plasma  

Microsoft Academic Search

RESUMO O objetivo deste estudo foi desenvolver e validar método simples, rápido e sensível para determinação de doxiciclina em plasma humano por cromatografia líquida de alta eficiência (CLAE). A doxiciclina e oxitetraciclina (padrão interno), foram extraídas de 0,5 mL de plasma com acetato de etila. Utilizaram-se o sistema de CLAE com bomba isocrática, com temperatura controlada (30°C) e coluna cromatográfica

Geysa Aguiar Romeu; Eunice Kazue Kano

4

Boson Model of Quantized EM-Field and Nature of Photons  

NASA Astrophysics Data System (ADS)

The fundamental result, obtained by Dirac, that the dynamical system, which consists of the ensemble of identical bosons is equivalent to the dynamical system, which consists of the ensemble of oscillators, was used to show, that the presence of scalar charge function ?(vec r, t) to be peer force characteristic of electromagnetic (EM) field along with vector force characteristics vec E(vec r,t), vec H(vec r,t), that was established earlier, agrees with charge neutrality of photons. The simplest analogue in its mathematical description in the physics of condensed matter is the chain of bosonic (spin S = 1) carbon atoms in trans-polyacetylene. It has been shown, that neutral photons are topological relativistic solitons with nonzero spin value, which is equal to ½ instead of prevalent viewpoint, that the photons possess by spin S = 1. Naturally, they have nonzero size, that is, they cannot be considered to be point objects. At the same time, the main excitations in so called "doped" rest massless "boson-atomic" structure of EM-field will be charged spinless EM-solitons. It seems to be reasonable to suggest, that "doping" can be effective by propagation of EM-field in the medium like to rain-clouds, although detailed mechanism has to be additionally studied. The representation of photons to be the result of spin-charge separation effect in rest massless "boson-atomic" structure of EM-field makes substantially more clear the nature of corpuscular-wave dualism.

Yerchuck, Dmitri; Dovlatova, Alia; Alexandrov, Andrey

2014-03-01

5

Além da Informalidade: Entendendo como os Fiscais e Agentes de Desenvolvimento Promovem a Formalização o Crescimento de Pequenas e Médias Empresas  

Microsoft Academic Search

Na maioria dos países em desenvolvimento, o número de pequenas e médias empresas (PMEs) no setor informal tem crescido continuamente na última década em conseqüência do excesso de regulação e da crescente concorrência internacional. Hoje, nesses locais, o grande desafio para formuladores de políticas e agentes de desenvolvimento é conciliar o crescimento econômico com as normas legais. Por um lado,

Mansueto Almeida

2008-01-01

6

Georeferencing natural disaster impact footprints : lessons learned from the EM-DAT experience  

NASA Astrophysics Data System (ADS)

The Emergency Events Database (EM-DAT) contains data about the occurrence and consequences of all the disasters that have taken place since 1900. The main objectives of the database are to serve the purposes of humanitarian action at national and international levels; to aid decision making for disaster preparedness, as well as providing an objective base for vulnerability assessments and priority setting. EM-DAT records data on the human and economic impacts for each event as well as the location of said event. This is recorded as text data, namely the province, department, county, district, or village. The first purpose of geocoding (or georeferencing) the EM-DAT database is to transform the location data from text format into code data. The GAUL (Global Administrative Unit Layers) database (FAO) is used as a basis to identify the geographic footprint of the disaster, ideally to the second administrative level and add a unique code for each affected unit. Our first step has involved georeferencing earthquakes since the location of these is precise. The second purpose is to detail the degree of precision of georeferencing. The application and benefits of georeferencing are manifold. The geographic information of the footprint of past (after 2000) and future natural disasters permits the location of vulnerable areas with a GIS system and to cross data from different sources. It will allow the study of different elements such as the extent of a disaster and its human and economic consequences; the exposure and vulnerability of the population in space and time and the efficiency of mitigation measures. In addition, any association between events and external factors can be identified (e.g.: is the famine located at the same places as drought?) and precision of the information in the disaster report can be evaluated. Besides this, these maps will provide valuable communication support since maps have a high communication power and are easily understandable by the wider public and policy makers. Some results from the application of georeferencing will be presented during the session such as a study of the population potentially exposed and affected by natural disasters in Europe, a flood vulnerability analysis in Vietnam and the potential merging of watersheds analysis and flood footprints data.

Wallemacq, Pascaline; Guha Sapir, Debarati

2014-05-01

7

Durabilidade natural de 46 espØcies de madeira amazÙnica em contato com o solo em ambiente florestal Natural durability of 46 Amazonian woods species in an in- ground essay in a forest environment  

Microsoft Academic Search

RESUMO: Neste trabalho estªo apresentados os dados referentes ‡ degradaÁªo, ‡ susceptibilidade a organismos xilÛfagos e ‡ durabilidade natural de 46 espØcies de madeira AmazÙnica, expostas por mais de 8 e de 10 anos em ensaio de campo. As seguintes espØcies foram classificadas como altamente durÆveis: Andira parviflora Ducke, Buchenavia oxycarpa Eichler, Clarisia racemosa Ruiz et Pavon, Dinizia excelsa Ducke,

Maria Aparecida de Jesus; Wellington de Morais; R. LiØge; Souza de Abreu; Maria de FÆtima; C. Cardias

8

Desenvolvimento de Interface com Usuário Dirigida por Modelos com Geração Automática de Código  

Microsoft Academic Search

Resumo. Este trabalho aplica técnicas de MDA ( Model Driven Architecture ) para gerar código a partir de modelos UML. Foi proposto um método, MDGI (Método de Desenvolvimento e Geração de Interfaces), que permite gerar modelos e código de padrões ( patterns ) recorrentes em sistemas. Esses padrões são gerados a partir de um modelo de domínio da aplicação. Neste

Lucas Issa; Clarindo Isaías P. S. Pádua; Rodolfo F. Resende; Stenio Viveiros; Pedro de Alcântara dos Santos Neto

2007-01-01

9

DESENVOLVIMENTO RURAL, MULHERES E TERRA - UM OLHAR SOBRE TIMOR-LESTE  

Microsoft Academic Search

O caminho percorrido para que as questões do género e do desenvolvimento e em especial a sua interligação sejam assuntos importantes e alvo de atenção tanto académica como política, foi longo. Várias áreas do conhecimento, como a sociologia, a antropologia e a economia, contribuem para a construção do conhecimento neste domínio, a par de outras mais recentes como os estudos

Vanda Margarida De Jesus Dos Santos Narciso; Pedro Damiao de Sousa Henriques

2008-01-01

10

Nature  

NSDL National Science Digital Library

Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance, and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public. Nature publishes more articles than any other multidisciplinary journal, and retains its position as the most cited weekly science journal. The site provides free access to news stories in the latest issue; access to research articles, and to the Nature archive, is by subscription.

11

Concertação e efetividade da ação política: o Conselho de Desenvolvimento Econômico e Social do governo Lula  

Microsoft Academic Search

A experiência internacional de Conselhos de Desenvolvimento remonta à metade do século passado com a criação dos primeiros conselhos na França (1946\\/1958) e Holanda (1950), vinculando-se à tradição de negociação e representação corporativa que fundamentou a experiência da social-democracia européia. Atualmente também existem conselhos na Áustria (1963), em Portugal (1991\\/1992), na Espanha (1991), na África do Sul (1995), além do

Sonia Fleury

2003-01-01

12

EM excitation and seismicity in the natural times - simulations with the theoretical model  

NASA Astrophysics Data System (ADS)

Discussed numerical simulations are based on solutions of the equations for interaction between charged dislocations in, as we call it, `natural time` domain. According to these simulations the precursory excitations and seismicity course develop in time for smaller and bigger events in a similar way. It seems this typical approach does not sufficiently reflect the regional effect of stress drop at seismic events; after seismic event one needs time for stress recovery to build up the stresses again. Following this numerical simulations the `natural time` scales differs from the real ones. Model is conditioned by assumption that dS/dx distribution at initial conditions (t=0) is characteristic for a given region and also that each region has specific pattern of fault planes characterized by lower values of rigidity around faults. This study is a part of paper by P. Varotsos, T. Teisseyre, C. Rozluski - in preparations.

Rozluski, C.

2003-04-01

13

Desenvolvimento de aplicações educativas em Geologia - Um exemplo  

Microsoft Academic Search

Resumo - Face à quase total inexistência de microscópios petrográficos nas escolas portuguesas dos ensinos básico e secundário, os alunos destes graus de ensino vêm-se privados do contacto com uma das técnicas básicas de observação e caracterização dos materiais geológicos. Para obviar esta lacuna iniciou-se a produção de uma aplicação multimédia, a ser disponibilizada on-line e off-line, com recurso a

J. B. R. Brilha; R. Henriques

14

SOBRE O PROCESSO DE MEDIAÇÃO SOCIAL NOS PROJETOS DE DESENVOLVIMENTO: UMA REFLEXÃO TEÓRICA  

Microsoft Academic Search

A mediação social é um tema que nos últimos anos vem ganhando espaço nas discussões sobre o desenvolvimento rural, mais especificamente, nas questões referentes à intervenção para o desenvolvimento. Este processo compreende uma relação que se apresenta como uma “via de mão dupla”, ou seja, a via representa a relação, uma das mãos é os mediadores, e a outra é

Cidonea Machado Deponti; Jalcione Almeida

2008-01-01

15

Abordagem do tema hipertensão arterial e suas relações com o tabagismo e a obesidade como forma de avaliação da aquisição e socialização de conhecimentos em Feiras de Ciências  

Microsoft Academic Search

O presente trabalho apresenta a experiência vivenciada por um professor do Ensino Fundamental de Escola Pública do Paraná, na orientação de uma equipe de alunos de 8ª série, em 2008, visando o desenvolvimento de trabalhos em Feiras de Ciências. A temática da equipe enfoca a hipertensão arterial e seus fatores de risco, tabagismo e obesidade, no município de Floresta. Escolheu-se

Eduardo de Almeida Grenier; Celso Ivam Conegero

2008-01-01

16

Um Estudo sobre Gerência de Configuração de Software aplicada ao Desenvolvimento Baseado em Componentes  

Microsoft Academic Search

This study aims to analyze the Software Configurati on Management (SCM) approach for conventional development and identify points that need to be tai lored to support Component Based Development (CBD). We believe that adapting SCM process to support CBD by applying variants for producer and consumer teams is the best way to take advantage of the benefits of SCM a

Ribeiro Dantas; Hamilton Oliveira; Leonardo Gresta; Paulino Murta; Cláudia Maria; Lima Werner

17

Desenvolvimento do Modelo WSIVM para Aperfeiçoar a Segurança em SOA e Serviços Web  

Microsoft Academic Search

The SOA architecture primarily based on Web Services is having a steady adoption, despite this growth is lower than expected when it was established, thats mainly because of difficulties defining security related aspects. Web Services inherited a lot of well-known security problems of web applications and brought new ones. The majority of attacks today are consequences of bad input validation

Rafael Bosse Brinhosa; Carla Merkle Westphall; Carlos Becker Westphall

18

EMS Course Coordinator's Implementation Guide.  

ERIC Educational Resources Information Center

This handbook is intended to clarify the responsibilities of an instructor-coordinator responsible for coordinating an emergency medical services (EMS) training program and to describe many of the materials now available for use in coordinating EMS training. Addressed in the individual chapters of the guide are the nature and scope of the…

Cockrum, Jim

19

FERUS: Um Ambiente de Desenvolvimento de Especica c~ oes CASL  

Microsoft Academic Search

Este artigo apresenta FERUS (Apoio Formal a Especic a c~ ao e Re-Utiliza c~ ao de Software), um am- biente desenvolvido no Departamento de Inform atica e Matem atica Aplicada da UFRN em parceria com o LORIA (Fran ca), que permite a cria c~ ao, manipula c~ ao e prototipa c~ ao de especic a c~ oes na linguagem CASL.

Gleydson Lima; Anamaria Martins; David Pereira; Demostenes Sen; Jorgiano Vidal

20

Natural resources  

NSDL National Science Digital Library

Natural resources are resources that occur in nature. Humans use these resources, but many of these resources are nonrenewable. They will eventually run out. Fossil fuels are naturally occurring fuels that are nonrenewable.

Olivia Worland (Purdue University;Biological Sciences)

2008-07-07

21

Nature Watch  

NSDL National Science Digital Library

Nature Watch is a partnership program of the U.S. Forest Service that provides nature viewing opportunities and encourages safe and sound viewing ethics. The Nature Watch program is for people to experience wildlife, fish, and flowers in their natural settings; to promote recreational viewing opportunities, facilitate learning about the environment, and to promote conservation efforts and wise use of natural resources. This site contains information on Nature Watch programs, coloring books, links to environmental science journals, and information on educational curricula.

22

About the nature of the coherence of light waves  

Microsoft Academic Search

The nature of electromagnetic (EM) phenomena, including light, is not fully clear. Postulated rejection of EM ether as a hypothetical habitat and distribution of EM waves, holds in the uncertainty and the problem of understanding the existence of most of these waves, because the notion of \\

Petro O. Demyanenko; Kostiantyn P. Demianenko; Fedir P. Demianenko; Yuri F. Zinkovskiy

2011-01-01

23

Structure of Matter, Forces, EM Waves, Spectroscopy, Doppler Effect  

NSDL National Science Digital Library

These supplemental class notes cover the basic properties of matter, the nature of forces, the electromagnetic spectrum, and how astronomers exploit the properties of the EM spectrum to deduce the physical nature of distant objects.

O'Connell, Robert

2005-06-28

24

Resultados do desenvolvimento de um propulsor à plasma no Brasil  

NASA Astrophysics Data System (ADS)

Uma das partes mais importantes de um satélite é o controle de atitude do mesmo. E se tratando de um satélite científico, a atenção para este sistema deve ser redobrada. Uma possibilidade atraente para executar esta tarefa é a propulsão elétrica. Aqui, mostraremos resultados obtidos pelo propulsor à plasma PHALL-01, desenvolvido na Universidade de Brasília entre 2000 e 2003. Este é derivado do propulsor russo SPT-100 (Stationary Plasma Thruster), mas com o emprego inovador de um arranjo de imãs permanentes como fonte do campo magnético, este último o agente da aceleração do plasma. Esta alteração foi motivada pelo objetivo de que o mesmo operasse com o mínimo de potência elétrica. A partir da formulação teórica do mecanismo de aceleração, tendo como base as equações da magnetohidrodinâmica, pode-se obter vínculos sob os quais o propulsor pudesse ser construído. O mais forte destes é o que dita a topologia do campo magnético. Sendo assim, foram realizadas simulações computacionais, que definiram a geometria do propulsor. Após construído, este foi diagnosticado usando-se sondas de Langmuir e analisadores de energia. Como resultados, obtivemos a distribuição espacial da temperatura, densidade e potencial do plasma, bem como a distribuição angular do feixe produzido pelo mesmo em vários regimes de operação. O espectro de energia do feixe de plasma também foi medido, indicando íons de até 560eV. Combinando estes resultados, calculou-se o empuxo do propulsor: 84mN; e o impulso específico: 1083s. Estes demonstram que o mesmo estará qualificado, num futuro próximo, para o emprego no controle de atitude de satélites científicos, ou até mesmo como parte do conjunto propulsor primário, responsáveis pela transferência de órbitas.

Ferreira, I. S.; Ferreira, J. L.

2003-08-01

25

Seguranca radiologica no uso de tecnicas nucleares -atividades desenvolvidas pelo Centro de Desenvolvimento da Tecnologia Nuclear - CNEN. (Radiological safety in the use of nuclear technique-activities developed by Centro de Desenvolvimento da Tecnologia Nuclear - CNEN).  

National Technical Information Service (NTIS)

The activities developed by the Centro de Desenvolvimento da Tecnologia Nuclear - CDTN supporting the users of nuclear techniques are described. The methodology used and future plans for the group are shown. (E.G.). (Atomindex citation 22:055424)

T. Wakabayashi E. G. Pereira T. Hirayama

1991-01-01

26

It's Natural  

NSDL National Science Digital Library

This activity introduces learners to Native Americans as people who depended upon nature in the past and continue to emphasize the importance of nature in the present. Learners go outside and use their senses to make observations about their environment. This experience inspires curiosity about nature, helps learners understand that we all need and use natural resources and helps them imagine what it would be like to depend entirely on the natural world. This introductory activity is featured on pp.9-10 of the "One With the Earth: Native Americans and the Natural World" multidisciplinary unit of study for kindergarten through third grade.

Indianapolis, The C.

2014-04-30

27

Natural Wonders  

NSDL National Science Digital Library

Many of the interesting landmarks around the world are formed over time by natural processes familiar to us in our everyday lives. This still collage produced for Teachers' Domain features images of a variety of beautiful natural wonders.

Foundation, Wgbh E.

2005-12-17

28

Natural gas  

NSDL National Science Digital Library

Natural gas is used as a means of power in households. Natural gas has no natural odor, so an odor is added to the gas. This is useful because gas leaks can be detected better and it also reduces the risk of accidents in homes.

N/A N/A (None;)

2003-07-27

29

Em18 and Em16, new serologic marker epitopes for alveolar echinococcosis in western blot analysis, are the only two epitopes recognized by commercially available weak positive (cut off) sera for Em2plus-ELISA.  

PubMed

The assay system for antibody responses against Em2, the most specific antigen for serodiagnosis of alveolar echinococcosis (AE), has been established by enzyme-linked immunosorbent assay (ELISA) but not by Western blot assay, since Em2 antigen is not protein but carbohydrate in nature. Recently we reported that previously undescribed protein epitopes, designated Em18 and Em16 due to their molecular weights, were good serologic markers for AE by Western blot analysis. It has been shown that Em18 and Em16 are the only two epitopes recognized by commercially available weak positive (cut off) sera for the Em2plus-ELISA. PMID:8583132

Ito, A; Osawa, Y; Nakao, M; Horii, T; Okamoto, M; Itoh, M; Yamashita, T

1995-12-01

30

Natural Attenuation  

Microsoft Academic Search

\\u000a Natural Attenuation (NA) has emerged during the last 10–15 years as a useful and cost-efficient alternative approach for contaminated\\u000a site management. It refers to the naturally occurring processes like dispersion, diffusion, sorption, volatilization, degradation\\u000a and transformation, all of which can substantially decrease contaminant concentration, mass, toxicity and\\/or mobility within\\u000a soil and groundwater. The efficiency of Natural Attenuation processes depends to

Anita Peter; Thomas Held; Norbert Hüsers; Frank A. Swartjes

31

Nature Watch  

NSDL National Science Digital Library

Nature Watch is a series of volunteer environmental monitoring programs coordinated by the Ecological Monitoring and Assessment Network (EMANCO), the Canadian Nature Federation, and the University of Guelph. Nature Watch is a growing network that currently includes Frog Watch, Ice Watch, Plant Watch, and Worm Watch. Site visitors can access the home pages of each of the participating programs for details about each program, how to collect and contribute data, and to view data that has already been collected.

32

ABC's Naturally  

NSDL National Science Digital Library

In this activity (located on page 4 of the PDF), learners enjoy the sensory experience of creating letters using natural materials after listening to a book about finding the alphabet in nature. Assemble the alphabet shapes onto pages to form an alphabet book.

Museum, Chicago C.

2009-01-01

33

Nature Detectives  

NSDL National Science Digital Library

Richard Louv's Last Child in the Woods (2008) added to a growing consensus to get children outside and experiencing nature. Using ideas from place-based education, the authors present a simple year-long project that brings science, nature, and ot

Harr, Natalie; Jr., Richard E.

2010-11-01

34

Natural Hazards  

NSDL National Science Digital Library

This lesson introduces students to a variety of natural hazards, emphasizing that when people understand these threats they are better able to avoid or reduce their potential impacts. First, the class discusses what they know about natural hazards and natural disasters. Then, working in pairs, they research particular hazards; the threats they pose and where and when those threats are most pronounced. Following this research period, the class assembles what they have learned into a general overview of natural hazards nationwide. Following the second class discussion, students work in pairs again to explore the hazards that affect particular towns, cities, or regions of the country. In doing so, they learn more about how and why certain natural hazards impact specific areas, as well as what people are doing to minimize the threats these hazards pose.

2006-01-01

35

Natural Gas  

NASA Astrophysics Data System (ADS)

Natural gas is a naturally occurring mixture of simple hydrocarbons and nonhydrocarbons that exists as a gas at ordinary pressures and temperatures. In the raw state, as produced from the earth, natural gas consists principally of methane (CH4) and ethane (C2H4), with fractional amounts of propane (C3H8), butane (C4H10), and other hydrocarbons, pentane (C5H12) and heavier. Occasionally, small traces of light aromatic hydrocarbons such as benzene and toluene may also be present.

Maddox, Robert N.; Moshfeghian, Mahmood; Ldol, James D.; Johannes, Arland H.

36

Firsthand Nature  

NSDL National Science Digital Library

It's no secret that many school programs don't give children enough opportunity to explore the natural world--i.e., to "mess about" and to have firsthand experience with nature and animals. Not so at the Muscota New School in New York City! This innovative public elementary school actively promotes inquiry-based learning and encourages teachers to use creative methods in the classroom to help children study the natural world around them. In this article, we share the experience of a teacher and her students over the course of two years (kindergarten and first grade) as they explored nature through direct observation of animals in the classroom, child-centered inquiry science, and school-sponsored field trips. As the years progressed, so did students' learning. Not only did students develop scientific literacy and communication skills, they also deepened their understanding of their environment.

Weiss, Francesca M.; Gostev, Moses

2007-04-01

37

Nature Podcast  

NSDL National Science Digital Library

Nature is a weekly international journal that publishes articles on all scientific topics. Although the journal itself is only available with a subscription, NatureâÂÂs weekly podcast series is completely free for anyone with Internet access. Topics of the podcasts vary from stem cells to Saturn, and include some of the content from that weekâÂÂs edition of Nature. The podcasts are always available in audio MP3 files, and the text of the transcript can also be downloaded. If you are new to these podcasts, be sure to check out the archives dating back to 2005 for interesting episodes you might have missed. Podcasts are accompanied by a discussion blog that lets you comment on the issues in each weekly installment. The issues presented in the podcasts are interesting and diverse. This is a great resource for students, teachers, parents, and everyone with an interest in science.

2008-02-05

38

Second Nature  

NSDL National Science Digital Library

Second Nature is a nonprofit organization designed to help colleges and universities make environmental sustainability a "foundation of learning and practice." A basic premise of Second Nature is that "moving society on a sustainable path will require major changes in the process and content of higher education." The newly updated site offers current EFS (Education for Sustainability) resources for teachers and educators, including dozens of examples of teaching methods and techniques, a bibliography of over 1800 educational resources, examples of 250 course syllabi, and a collection of essays and publications. The site also allows users to communicate with educators via the bulletin board or browse upcoming events on the Calendar.

1969-12-31

39

Natural quasicrystals.  

PubMed

Quasicrystals are solids whose atomic arrangements have symmetries that are forbidden for periodic crystals, including configurations with fivefold symmetry. All examples identified to date have been synthesized in the laboratory under controlled conditions. Here we present evidence of a naturally occurring icosahedral quasicrystal that includes six distinct fivefold symmetry axes. The mineral, an alloy of aluminum, copper, and iron, occurs as micrometer-sized grains associated with crystalline khatyrkite and cupalite in samples reported to have come from the Koryak Mountains in Russia. The results suggest that quasicrystals can form and remain stable under geologic conditions, although there remain open questions as to how this mineral formed naturally. PMID:19498165

Bindi, Luca; Steinhardt, Paul J; Yao, Nan; Lu, Peter J

2009-06-01

40

Natural ecosystems  

USGS Publications Warehouse

Natural Ecosystems analyzes the association of observed changes in climate with changes in the geographic distributions and phenology (the timing of blossoms or migrations of birds) for Southwestern ecosystems and their species, portraying ecosystem disturbances—such as wildfires and outbreaks of forest pathogens—and carbon storage and release, in relation to climate change.

Fleishman, Erica; Belnap, Jayne; Cobb, Neil; Enquist, Carolyn A.F.; Ford, Karl; MacDonald, Glen; Pellant, Mike; Schoennagel, Tania; Schmit, Lara M.; Schwartz, Mark; van Drunick, Suzanne; Westerling, Anthony LeRoy; Keyser, Alisa; Lucas, Ryan

2013-01-01

41

Nature's Palette  

NSDL National Science Digital Library

Flower petals, acorn hats, exoskeletons of beetles, and lichens are just a few of the objects students may find in a surprising array of vivid colors. These tiny examples from nature's palette can be discovered in a school yard, a park, or even along the

Mcbride, Brooke B.; Brewer, Carol A.

2010-10-01

42

Natural polysulfides  

NASA Astrophysics Data System (ADS)

The structures of natural polysulfides of animal and plant origin are considered. Data are presented on the biological activity of compounds containing di-, tri-, tetra- and pentasulfide groups. Schemes of total synthesis of the above-mentioned compounds and their structural analogues are discussed. The bibliography includes 156 references.

Tolstikov, Genrikh A.; Shul'ts, Elvira E.; Tolstikov, Alexander G.

1997-09-01

43

Digital C4I Interoperability: The EM Protection Issue.  

National Technical Information Service (NTIS)

In this paper, a unified protection methodology is applied to a digital mobile C4I platform subjected to several human-generated and nature- generated EM environments and effects. The unclassified values for self-induced electromagnetic interference (EMI)...

R. Pfeffer

2000-01-01

44

Natural antioxidants.  

PubMed

The constant exposure of the skin to oxidative stress results in damage to cellular DNA and cell membrane lipids and proteins. To combat this problem, the skin contains a number of antioxidants that protect against oxidative injury. However, these cutaneous antioxidants can be depleted by sun exposure and environmental insults, resulting in an overload of oxidation products. Thus, topical antioxidants that replenish the antioxidant capacity of the skin have the potential to prevent oxidative damage. A number of natural antioxidant ingredients also have anti-inflammatory properties, and can be used in the treatment of oxidative damage such as photoaging and perhaps even skin cancer. This article summarizes the active components, pharmacologic properties, and clinical effectiveness of a number of natural antioxidant ingredients including soy, feverfew, mushroom extracts, teas, Coffea arabica (CoffeeBerry), Pinus pinaster (Pycnogenol), and Polypodium leucotomos. Recent clinical trials suggest that these compounds have promising efficacy in the topical treatment of oxidative stress-induced dermatoses. PMID:18681153

Berson, Diane S

2008-07-01

45

Natural gas  

SciTech Connect

The abundance of the world reserves of natural gas and the excellence of its qualities as a fuel and a petrochemical feedstock should enable natural gas to increase its penetration on international energy markets. However, the geographic distribution of its proved reserves coincides less and less with the distribution of its consumption. Therefore, the increase in international gas trade appears more and more to be of vital necessity for the world development of its markets. On the basis of a study carried out within the Association Technique de l'Industrie du Gas en France (ATG), the present paper will attempt to analyse the outlook for international gas trade between now and the year 2000.

Valais, M.; Khayat, A.

1988-01-01

46

Nature Milestones  

NSDL National Science Digital Library

What were the most important advances in cutaneous biology of the past 100 years? The Nature Milestones website provides a detailed answer to that question, along with similar responses regarding light microscopy, cancer, and gene expression. All told there are ten special features on the site, and each feature includes an interactive timeline, scientific commentaries, and a selection of articles from Nature magazine and other peer-reviewed publications. Additionally, each feature includes a list of academic advisors, sponsors, and links to external resources on the subject. Visitors may wish to use these resources in the classroom setting, as they provide basic and advanced materials that can be used by a number of introductory courses. Finally, a number of the materials are also available in the pdf format for easy printing.

47

Evolução química em galáxias compactas azuis (BCGs)  

NASA Astrophysics Data System (ADS)

Neste trabalho, a formação estelar e evolução quí mica em galáxias Compactas Azuis (Blue Compact Galaxies - BCGs) foram estudadas através da comparação de previsões de modelos de evolução quí mica a várias razões de abundância quí mica observadas nestas galáxias. Modelos detalhados com recentes dados de nucleossí ntese e que levam em consideração o papel desempenahdo por supernovas de ambos os tipos (II e Ia) na evolução galáctica foram desenvolvidos para as BCGs permitindo seguir a evolução de vários elementos quí micos (H, D, He, C, N, O, Mg, Si, S, Ca, e Fe). O modelo é caracterizado pelas prescrições adotadas para a formação estelar, a qual ocorre em vários surtos de atividade separados por longos perí odos quiescentes. Após ajustar os melhores modelos aos dados observacionais, as previsões destes modelos foram comparadas também a razões de abundância observadas em sistemas Damped Lyman alpha (DLAs) e a origem do N (primária ou secundária) foi discutida. Alguns dos resultados obtidos são: i) as razões de abundância observadas nas BCGs são reproduzidas por modelos com 2 a 7 surtos de formação estelar com eficiência entre n = 0.2-0.9 Gano-1; ii) os baixos valores de N/O observados nestas galáxias são um resultado natural de uma formação estelar em surtos; iii) os modelos para BCGs podem reproduzir os dados dos DLAs, iv) uma quantidade "baixa" de N primário produzido em estrelas de alta massa pode ser uma explicação para os baixos valores de [N/a] observados em DLAs.

Lanfranchi, G. A.; Matteucci, F.

2003-08-01

48

Natural Disasters  

NSDL National Science Digital Library

Students are introduced to our planet's structure and its dynamic system of natural forces through an examination of the natural hazards of earthquakes, volcanoes, landslides, tsunamis, floods and tornados, as well as avalanches, fires, hurricanes and thunderstorms. They see how these natural events become disasters when they impact people, and how engineers help to make people safe from them. Students begin by learning about the structure of the Earth; they create clay models showing the Earth's layers, see a continental drift demo, calculate drift over time, and make fault models. They learn how earthquakes happen; they investigate the integrity of structural designs using model seismographs. Using toothpicks and mini-marshmallows, they create and test structures in a simulated earthquake on a tray of Jell-O. Students learn about the causes, composition and types of volcanoes, and watch and measure a class mock eruption demo, observing the phases that change a mountain's shape. Students learn that the different types of landslides are all are the result of gravity, friction and the materials involved. Using a small-scale model of a debris chute, they explore how landslides start in response to variables in material, slope and water content. Students learn about tsunamis, discovering what causes them and makes them so dangerous. Using a table-top-sized tsunami generator, they test how model structures of different material types fare in devastating waves. Students learn about the causes of floods, their benefits and potential for disaster. Using riverbed models made of clay in baking pans, students simulate the impact of different river volumes, floodplain terrain and levee designs in experimental trials. They learn about the basic characteristics, damage and occurrence of tornadoes, examining them closely by creating water vortices in soda bottles. They complete mock engineering analyses of tornado damage, analyze and graph US tornado damage data, and draw and present structure designs intended to withstand high winds.

Integrated Teaching And Learning Program

49

Natural Selection  

NSDL National Science Digital Library

Learners simulate the process of natural selection using a variety of beans and a bowl with a hole cut into it. The variety of beans represents the variation in a population of microbes, and the bowl with a hole represents an antibiotic or some other selective pressure on the population. Only the beans that survive (don't fall through the hole) are allowed to reproduce for the next generation. Learners record and plot the number of each kind of bean through multiple generations. This activity also addresses the process of scientific investigation as learners are encouraged to design their own method of experimentation, make a hypothesis, record data, and share their results.

Thiel-Cobbey, Heather

2012-01-01

50

Nature Soundmap  

NSDL National Science Digital Library

The Nature Soundmap offers unique access to the untouched and diverse wildlife that spans the globe, an experience that the Scout team could not pass up. In addition to high-quality audio, we enjoyed the articles within the newsletter that detail the remarkable travel ventures behind the recording process. We also appreciated that the site devotes itself to providing the best listening experience possible, offering tips on âÂÂHow to Listenâ and even a form for user suggestions.What does a humpback whale sound like? Or perhaps the White-cheeked Gibbon? The Nature Soundmap provides snippets of these sounds and much, much more. Visitors will find an interactive map of the world, complete with markers that allow audio wildlife travel from Central America to Central Asia a snap. Symphonies of animal noises can also be found here, as visitors can click on Greece to listen to "Summer Ambience" or France to find "Dawn in the Lezardrieux Forest.â Each marker includes information about the animal or setting profiled, along with a link to More Info for the generally curious.

51

Natural inflation  

SciTech Connect

A pseduo-Nambu-Goldstone boson, with a potential of the form V({phi}) = {Lambda}{sup 4}(1 {plus minus} cos({phi}/f)), can naturally give rise to an epoch of inflation in the early universe. Successful inflation can be achieved if f {approximately} m{sub pl} and {Lambda} {approximately} m{sub GUT}. Such mass scales arise in particle physics models with a gauge group that becomes strongly interacting a the GUT scale, e.g., as is expected to happen in the hidden sector of superstring theories. The density fluctuation spectrum is a non-scale-invariant power law, with extra power on large scales. 12 refs., 3 figs.

Frieman, J.A.

1991-02-01

52

Natural games  

NASA Astrophysics Data System (ADS)

A course of a game is formulated as a physical process that will consume free energy in the least time. Accordingly, the rate of entropy increase is the payoff function that will subsume all forms of free energy that motivate diverse decisions. Also other concepts of game theory are related to their profound physical counterparts. When the physical portrayal of behavior is mathematically analyzed, the course of a game is found to be inherently unpredictable because each move affects motives in the future. Despite the non-holonomic character of the natural process, the objective of consuming free energy in the least time will direct an extensive-form game toward a Lyapunov-stable point that satisfies the minimax theorem.

Anttila, Jani; Annila, Arto

2011-10-01

53

EMS System Plan.  

National Technical Information Service (NTIS)

An Emergency Medical Service (EMS) system plan for an eight-county, primarily rural district of south central Oklahoma is presented. Demographic and area characteristics of the district are described. The existing EMS resources such as: manpower (physicia...

G. L. Dahl R. Eidson

1975-01-01

54

EMS Student Handbook.  

ERIC Educational Resources Information Center

This student guide is one of a series of self-contained materials for students enrolled in an emergency medical services (EMS) training program. Discussed in the individual sections of the guide are the following topics: the purpose and history of EMS professionals; EMS training, certification and examinations (national and state certification and…

Ogle, Patrick

55

EM International. Volume 1  

SciTech Connect

It is the intent of EM International to describe the Office of Environmental Restoration and Waste Management`s (EM`s) various roles and responsibilities within the international community. Cooperative agreements and programs, descriptions of projects and technologies, and synopses of visits to international sites are all highlighted in this semiannual journal. Focus on EM programs in this issue is on international collaboration in vitrification projects. Technology highlights covers: in situ sealing for contaminated sites; and remote sensors for toxic pollutants. Section on profiles of countries includes: Arctic contamination by the former Soviet Union, and EM activities with Germany--cooperative arrangements.

Not Available

1993-07-01

56

World Natural Gas: 1977.  

National Technical Information Service (NTIS)

In this report, tables are presented for natural gas production by countries; gross production of natural gas by type of well; natural gas used for repressuring or wasted by countries, and world natural gas trade. (ERA citation 05:034565)

1979-01-01

57

Desenvolvimento das câmeras de raios-X duros do satélite MIRAX  

NASA Astrophysics Data System (ADS)

O MIRAX (Monitor e Imageador de RAios-X) é um projeto de desenvolvimento de um pequeno satélite astronômico de raios-X (~200 kg, ~240 W). A estratégia básica da missão será observar continuamente (~9 meses por ano) a região central (~1000 graus2) do plano Galáctico e realizar estudos espectroscópicos de banda larga (2-200 keV) e alta sensibilidade de um grande conjunto de fontes através de imagens com resolução de ~6'. Isso proporcionará uma cobertura inédita do "espaço de descobertas" através da detecção, localização, identificação e estudo detalhado de fenômenos imprevisíveis, tais como transientes fracos de raios-X, novas rápidas de raios-X e bursts de raios gama, assim como o estudo de fontes com emissão persistente. Neste trabalho apresentamos o projeto das duas câmeras de raios-X duros (CXDs) do MIRAX, que irão operar na faixa de 10 a 200 keV. Cada CXD consistirá de um plano de detectores CZT (Cd0,9Zn0,1Te) de 0,5 mm de resolução espacial e 370 cm2 de área total, e de uma máscara codificada com elementos quadrados de 1,3 mm de lado e 0,5 cm de espessura. A máscara terá dimensões de 315 cm ´ 275 cm e será montada a 700 cm de distância dos detectores. Com essa configuração as CXDs terão 6' de resolução angular e, quando colocadas a um ângulo de 29° entre si, as duas câmeras propiciam um campo totalmente codificado de 39° ´ 6°12' e um campo total de 76° ´ 44°. Serão apresentadas simulações de observações da região do plano Galáctico com o conjunto formado pelas duas CXDs.

Braga, J.; Rothschild, R.; Staubert, R.; Heise, J.; Remillard, R.; D'Amico, F.; Jablonski, F.; Mejía, J.; Carvalho, H.; Heindl, B.; Matteson, J.; Kendziorra, E.; Wilms, J.; in't Zand, J.; Kuulkers, E.

2003-08-01

58

TandEM: Titan and Enceladus mission  

Microsoft Academic Search

TandEM was proposed as an L-class (large) mission in response to ESA’s Cosmic Vision 2015–2025 Call, and accepted for further\\u000a studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds\\u000a tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini–Huygens\\u000a mission. These

A. Coustenis; S. K. Atreya; T. Balint; R. H. Brown; M. K. Dougherty; F. Ferri; M. Fulchignoni; D. Gautier; R. A. Gowen; C. A. Griffith; L. I. Gurvits; R. Jaumann; Y. Langevin; M. R. Leese; J. I. Lunine; C. P. McKay; X. Moussas; I. Müller-Wodarg; F. Neubauer; T. C. Owen; F. Raulin; E. C. Sittler; F. Sohl; C. Sotin; G. Tobie; T. Tokano; E. P. Turtle; J.-E. Wahlund; J. H. Waite; K. H. Baines; J. Blamont; A. J. Coates; I. Dandouras; T. Krimigis; E. Lellouch; R. D. Lorenz; A. Morse; C. C. Porco; M. Hirtzig; J. Saur; T. Spilker; J. C. Zarnecki; E. Choi; N. Achilleos; R. Amils; P. Annan; D. H. Atkinson; Y. Bénilan; C. Bertucci; B. Bézard; G. L. Bjoraker; M. Blanc; L. Boireau; J. Bouman; M. T. Capria; E. Chassefière; P. Coll; M. Combes; J. F. Cooper; A. Coradini; F. Crary; T. Cravens; I. A. Daglis; E. de Angelis; C. de Bergh; I. de Pater; C. Dunford; G. Durry; O. Dutuit; D. Fairbrother; F. M. Flasar; A. D. Fortes; R. Frampton; M. Fujimoto; M. Galand; O. Grasset; M. Grott; T. Haltigin; A. Herique; F. Hersant; H. Hussmann; W. Ip; R. Johnson; E. Kallio; S. Kempf; M. Knapmeyer; W. Kofman; R. Koop; T. Kostiuk; N. Krupp; M. Küppers; H. Lammer; L.-M. Lara; P. Lavvas; S. Le Mouélic; S. Lebonnois; S. Ledvina; J. Li; T. A. Livengood; R. M. Lopes; J.-J. Lopez-Moreno; D. Luz; P. R. Mahaffy; U. Mall; J. Martinez-Frias; B. Marty; T. McCord; C. Menor Salvan; A. Milillo; D. G. Mitchell; R. Modolo; O. Mousis; M. Nakamura; C. D. Neish; C. A. Nixon; D. Nna Mvondo; G. Orton; M. Paetzold; J. Pitman; S. Pogrebenko; W. Pollard; O. Prieto-Ballesteros; P. Rannou; K. Reh; L. Richter; F. T. Robb; R. Rodrigo; S. Rodriguez; P. Romani; M. Ruiz Bermejo; E. T. Sarris; P. Schenk; B. Schmitt; N. Schmitz; D. Schulze-Makuch; K. Schwingenschuh; A. Selig; B. Sicardy; L. Soderblom; L. J. Spilker; D. Stam; A. Steele; K. Stephan; D. F. Strobel; K. Szego; C. Szopa; R. Thissen; M. G. Tomasko; D. Toublanc; H. Vali; I. Vardavas; V. Vuitton; R. A. West; R. Yelle; E. F. Young

2009-01-01

59

Connecting with Nature.  

ERIC Educational Resources Information Center

Describes strategies for connecting children and adults with nature, including providing opportunities to experience nature through all of the senses, changing the perspective on nature by using the senses to focus on the natural world, and using the natural world to cultivate a sense of awe and wonderment. (LP)

Rodenburg, Jacob

1994-01-01

60

EM and beyond  

Microsoft Academic Search

The basic theme of the EM algorithm, to repeatedly use complete-data methods to solve incomplete data problems, is also a theme of several more recent statistical techniques. These techniques—multiple imputation, data augmentation, stochastic relaxation, and sampling importance resampling—combine simulation techniques with complete-data methods to attack problems that are difficult or impossible for EM.

Donald B. Rubin

1991-01-01

61

MAXIMUM (EM) POWER: A FOUNDATION PRINCIPLE LINKING MAN AND NATURE  

EPA Science Inventory

The fruitfulness of H.T. Odum?s commitment to a systems-based understanding of our biosphere, its dynamics, and the potential role of humans within it is indicated by his extensive and seminal contributions to the many branches of environmental science and socioeconomic policy st...

62

World Natural Gas: 1976.  

National Technical Information Service (NTIS)

Natural gas production by countries is presented in tabular form for the years 1972 through 1976. Data are also presented on natural gas used for repressuring or wasted and on world natural gas trade. (ERA citation 04:051121)

1978-01-01

63

Natural Language Processing.  

ERIC Educational Resources Information Center

Discusses issues related to natural language processing, including theoretical developments; natural language understanding; tools and techniques; natural language text processing systems; abstracting; information extraction; information retrieval; interfaces; software; Internet, Web, and digital library applications; machine translation for…

Chowdhury, Gobinda G.

2003-01-01

64

Comparação do desempenho de pré-escolares, mediante teste de desenvolvimento de Denver, antes e após intervenção nutricional  

Microsoft Academic Search

RESUMO — A análise de performance psicomotora de crianças institucionalizadas é de fundamental importância no planejamento de atividades edu- cativas. Estudos anteriores têm mostrado prejuízos desta função em crianças de creches. OBJETIVO. Comparar o desempenho no teste de triagem de Denver em crianças de 2 a 6 anos de idade, de creches conveniadas com a Prefeitura de São Paulo, antes

M. Fisberg; M. R. Pedromônico; J. A. P. Braga; A. M. A. Ferreira; C. Pini; S. C. C. Campos; S. O. Lemes; S. Silva; R. S. Silva; T. M. Andrade

1997-01-01

65

Composição florística da vegetação arbórea de um trecho de floresta estacional semidecídua em Viçosa, Minas Gerais, e espécies de maior ocorrência na região  

Microsoft Academic Search

RESUMO - É grande a demanda por estudos ecológicos em florestas que possam embasar trabalhos de recuperação, conservação da biodiversidade e apoio à legislação ambiental. Entre esses estudos, primordialmente está o levantamento da flora. Nesse sentido, este trabalho teve como objetivo determinar a composição florística de um trecho da Reserva da Biologia, em Viçosa, MG, em regeneração natural há 80

Walnir Gomes Ferreira Júnior; Alexandre Francisco da Silva; João Augusto Alves Meira Neto; Carlos Ernesto Gonçalves Reynaud Schaefer; Arildo de Souza Dias; Maíra Ignácio; Maria Cláudia Melo Pacheco de Medeiros

2007-01-01

66

Sketching in Nature  

NSDL National Science Digital Library

Science students will discover the beauty of communing with nature by utilizing a Nature journal during field observations. Nature journaling is a useful skill, independent of whether students consider themselves artists. Sketching from nature is one way to provide open-ended, inquiry-based learning while also bringing art into the process of learning science. This article includes two exercises, contour drawing and an observation activity, to get teachers started in the process of "sketching nature" into the science curriculum.

Hobart, April

2005-01-01

67

Deterministic annealing EM algorithm.  

PubMed

This paper presents a deterministic annealing EM (DAEM) algorithm for maximum likelihood estimation problems to overcome a local maxima problem associated with the conventional EM algorithm. In our approach, a new posterior parameterized by `temperature' is derived by using the principle of maximum entropy and is used for controlling the annealing process. In the DAEM algorithm, the EM process is reformulated as the problem of minimizing the thermodynamic free energy by using a statistical mechanics analogy. Since this minimization is deterministically performed at each temperature, the total search is executed far more efficiently than in the simulated annealing. Moreover, the derived DAEM algorithm, unlike the conventional EM algorithm, can obtain better estimates free of the initial parameter values. We also apply the DAEM algorithm to the training of probabilistic neural networks using mixture models to estimate the probability density and demonstrate the performance of the DAEM algorithm. PMID:12662837

Ueda, N; Nakano, R

1998-03-01

68

The Nature of Natural Hazards Communication (Invited)  

NASA Astrophysics Data System (ADS)

Some of the many issues of interest to natural hazards professionals include the analysis of proactive approaches to the governance of risk from natural hazards and approaches to broaden the scope of public policies related to the management of risks from natural hazards, as well as including emergency and environmental management, community development and spatial planning related to natural hazards. During the talk we will present results of scientific review, analysis and synthesis, which emphasize same new trends in communication of the natural hazards theories and practices within an up-to-the-minute context of new environmental and climate change issues, new technologies, and a new focus on resiliency. The presentation is divided into five sections that focus on natural hazards communication in terms of education, risk management, public discourse, engaging the public, theoretical perspectives, and new media. It includes results of case studies and best practices. It delves into natural hazards communication theories, including diffusion, argumentation, and constructivism, to name a few. The presentation will provide information about: (1) A manual of natural hazards communication for scientists, policymakers, and media; (2) An up-to-the-minute context of environmental hazards, new technologies & political landscape; (3) A work by natural hazards scientists for geoscientists working with social scientists and communication principles; (4) A work underpinned by key natural hazards communication theories and interspersed with pragmatic solutions; (5) A work that crosses traditional natural hazards boundaries: international, interdisciplinary, theoretical/applied. We will further explore how spatial planning can contribute to risk governance by influencing the occupation of natural hazard-prone areas, and review the central role of emergency management in risk policy. The goal of this presentation is to contribute to the augmentation of the conceptual framework of risk governance and increase the awareness of practitioners and decision-makers to the need to adopt proactive policies, leading to a more integrated, participative, and adaptive governance that can respond more efficiently to the increasing uncertainty resulting from escalating natural hazards risk exposure.

Kontar, Y. Y.

2013-12-01

69

O que bil?ngues bimodais t?m a nos dizer sobre desenvolvimento bil?ngue?  

PubMed Central

O objetivo deste trabalho é apresentar o que as pesquisas que estamos desenvolvendo com crianças ouvintes, filhas de pais surdos, adquirindo Língua Brasileira de Sinais (Libras) e Português e Língua de Sinais Americana (ASL) e Inglês (Lillo-Martin et al. 2010) têm a nos dizer sobre desenvolvimento bilíngue. Os dados deste estudo fazem parte de um banco de dados de interações espontâneas coletadas longitudinalmente, alternando contextos de aquisição da Libras e do português como língua alvo, no Brasil e dados coletados longitudinalmente. nos mesmos contextos, de crianças adquirindo ASL e inglês1. Além disso, há também dados do estudo experimental com testes aplicados nos dois pares de línguas que se agregam ao presente estudo. Uma visão geral dos estudos desenvolvidos sobre a aquisição bilíngue bimodal por crianças ouvintes, filhas de pais surdos, será apresentada e, então, serão expostos alguns aspectos linguísticos deste tipo de aquisição, considerando as discussões sobre aquisição bilíngue a partir da pesquisa realizada.

de Quadros, Ronice Muller; Lillo-Martin, Diane; Pichler, Deborah Chen

2013-01-01

70

Integrated dryland weed control in nature farming systems  

Microsoft Academic Search

As practices of integrated weed control in nature farming systems, surface application of a bioactive organic fertilizer, pigtailed wheat straw mulch, and intercropped peanut as a smother crop were tested with soybean, Japanese pumpkin and tomato, respectively. A bioactive organic fertilizer using rice bran, oil mill sludge and fish meal as materials and a microbial inoculant (EM as its commercial

Hui-lian Xu; Feifei Qin; Fahong Wang; Qicong Xu; Shailendra K. Shah; Fengmin Li

2009-01-01

71

Considerações a respeito da ansiedade em jovens atletas a partir dos estágios psicossociais do desenvolvimento Considerations about the anxiety in young athletes from stages of psychosocial development  

Microsoft Academic Search

This review aims to consider the process of structu ring the anxiety within the theory of Psychosocial Development Erik Erikson and discuss the issue of l imitation of the studies of anxiety in sports. Thus , it is understood that the mechanisms of anxiety in the sp orting context can influence the performance of athletes and therefore a methodology for

Robério Silva de Paiva; Thaísa Vilhena Silva

72

O desenvolvimento compartilhado de impressos como estratégia de educação em saúde junto a trabalhadores de escolas da rede pública do Estado do Rio de Janeiro  

Microsoft Academic Search

This article describes the process and results of an experience with preparing a mural entitled A Day in the Life of the School Lunch Cook, conducted with public school employees in the State of Rio de Janeiro by a team of researchers and students from the Specialization Course in Workers' Health at the Center for Studies on Workers' Health of

Kátia Reis de Souza; Brani Rozemberg; Adriana Kelly-Santos; Nancy Yasuda; Marta Sharapin

2003-01-01

73

Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents  

Microsoft Academic Search

The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Attenuation (EA) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA\\/EA. A broadly representative working group of scientists supports the project along with partnerships with regulatory

Karen Vangelas; T. H. Widemeirer; M. J. Barden; W. Z. Dickson; David Major

2004-01-01

74

A Natural Love of Natural Products  

PubMed Central

Recent research on the chemistry of natural products from the author’s group that led to the receipt of the ACS Ernest Guenther Award in the Chemistry of Natural Products is reviewed. REDOR NMR and synthetic studies established the T-taxol conformation as the bioactive tubulin-binding conformation, and these results were confirmed by the synthesis of compounds which clearly owed their activity or lack of activity to whether or not they could adopt the T-taxol conformation. Similar studies with the epothilones suggest that the current tubulin-binding model needs to be modified. Examples of natural products discovery and biodiversity conservation in Suriname and Madagascar are also presented, and it is concluded that natural products chemistry will continue to make significant contributions to drug discovery.

2008-01-01

75

Natural Disaster Operations Planning.  

National Technical Information Service (NTIS)

This research was concerned with development of a general concept of emergency operations for natural disaster situations and a prototype natural diaster operations plan (NADOP). The concept is based on classifying the several types of disaster agents acc...

C. T. Rainey

1972-01-01

76

Colours From Nature  

ERIC Educational Resources Information Center

In reference to American Indian ceremonial art, the importance of using natural pigments is emphasized, since the superior color values of natural dyes better reflect religious and philosophical depth and meaning. (JC)

Simon, Wilma

1974-01-01

77

Nature of War Theory.  

National Technical Information Service (NTIS)

Today s advances in evolutionary biology are unifying competing theories of natural selection and serve as a timely call for a similar unification of competing theories of war. This paper explores the relationship between war and natural selection by firs...

P. B. Olsen

2011-01-01

78

Biomimicry: Natural Designs  

NSDL National Science Digital Library

Students learn about biomimicry and how engineers often imitate nature in the design of innovative new products. They demonstrate their knowledge of biomimicry by practicing brainstorming and designing a new product based on what they know about animals and nature.

Integrated Teaching And Learning Program

79

How Nature Helps Children.  

ERIC Educational Resources Information Center

Discusses three major ways in which nature helps children develop. Discusses observations of theorists and researchers, including Maria Montessori, that nature stimulates children's powers of observation, fosters creativity, and instills a sense of peace and being at one with the world. Offers recommendations, including protecting nature,…

Crane, William

2001-01-01

80

Natural and Academic Learning.  

ERIC Educational Resources Information Center

For centuries, there has been a raging debate over the origin of knowledge and the nature of learning. This paper describes the essence of that debate as it relates to understanding the current disjunction between natural learning and academic learning. Natural learning represents the wealth of learning that occurs outside of school, especially…

Collier, Sunya; Iran-Nejad, Asghar

81

Natural Gas Annual 1996  

NSDL National Science Digital Library

_Natural Gas Annual_ provides information on the "supply and disposition of natural gas in the United States." It contains State level data for production, transmission, storage, deliveries, and price of natural gas. Historical data at the national level are available from the 1930's.

82

Monitored Natural Attenuation  

Microsoft Academic Search

Monitored natural attenuation (MNA) is an in situ remediation technology that relies on naturally occurring and demonstrable processes in soil and groundwater which reduce the mass and concentration of the contaminants. Natural attenuation (NA) involves both aerobic and anaerobic degradation of the contaminants due to the fact that oxygen is used up near the core of the contaminant plume. The

Kirsten S. Jørgensen; Jani M. Salminen; Katarina Björklöf

2010-01-01

83

Evolution by Natural Selection  

NSDL National Science Digital Library

Principles of natural selection are demonstrated by a simulation that involves different color pom-poms and student feeders equipped with different types of feeding implements. Students analyze results to see how different traits contribute to fitness in different habitats. Additional examples and questions help students to understand the process of natural selection, including three necessary conditions for natural selection to take place.

Doherty, Jennifer; Waldron, Ingrid

84

Nature in the City.  

ERIC Educational Resources Information Center

Describes a science program developed by the Cleveland Museum of Natural History, "Nature in the City," in which students and teachers learn together about the natural community surrounding their school. Includes program's rationale, list of "adventures," and methods. Discusses strategies of Sherlock Holmes'"adventure" focusing on animal tracks…

Ferbert, Mary Lou

1981-01-01

85

Changing Nature of Peace.  

National Technical Information Service (NTIS)

As the nature of war changes, the conditions for the nature of peace may also change. Inherent in the changing nature of war and peace are implications for war termination, end state, and peace which present perplexing questions for national leaders and o...

S. F. Wilson

1993-01-01

86

EM Radiation Program  

NSDL National Science Digital Library

The EM Radiation program displays the electric field vectors (in the x-y plane) and magnetic field contours (for the field in the z direction) calculated from the Lienard-Wiechert potentials for a charged particle. The default scenario shows the resulting radiation from a charged particle in simple harmonic motion. Additional particle trajectories can be specified using the Display | Switch GUI menu item. EM Radiation is an Open Source Physics program written for the teaching of electromagnetism. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the em_radiation.jar file will run the program if Java is installed. Other electromagnetism programs are also available. They can be found by searching ComPADRE for Open Source Physics, OSP, or electromagnetism.

Christian, Wolfgang

2008-05-20

87

Novel natural food antimicrobials.  

PubMed

Naturally occurring antimicrobial compounds could be applied as food preservatives to protect food quality and extend the shelf life of foods and beverages. These compounds are naturally produced and isolated from various sources, including plants, animals and microorganisms, in which they constitute part of host defense systems. Many naturally occurring compounds, such as nisin, plant essential oils, and natamycin, have been widely studied and are reported to be effective in their potential role as antimicrobial agents against spoilage and pathogenic microorganisms. Although some of these natural antimicrobials are commercially available and applied in food processing, their efficacy, consumer acceptance and regulation are not well defined. This manuscript reviews natural antimicrobial compounds with reference to their applications in food when applied individually or in combination with other hurdles. It also reviews the mechanism of action of selected natural antimicrobials, factors affecting their antimicrobial activities, and future prospects for use of natural antimicrobials in the food industry. PMID:22385168

Juneja, Vijay K; Dwivedi, Hari P; Yan, Xianghe

2012-01-01

88

emGain: Determination of EM gain of CCD  

NASA Astrophysics Data System (ADS)

The determination of the EM gain of the CCD is best done by fitting the histogram of many low-light frames. Typically, the dark+CIC noise of a 30ms frame itself is a sufficient amount of signal to determine accurately the EM gain with about 200 512x512 frames. The IDL code emGain takes as an input a cube of frames and fit the histogram of all the pixels with the EM stage output probability function. The function returns the EM gain of the frames as well as the read-out noise and the mean signal level of the frames.

Daigle, Olivier; Carignan, Claude; Blais-Ouellette, Sebastien

2012-01-01

89

Natural vacuum electronics  

NASA Technical Reports Server (NTRS)

The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.

Leggett, Nickolaus

1990-01-01

90

Preparing for Natural Disasters  

NSDL National Science Digital Library

How can you prepare for different natural disasters? Let's learn about different ways to prepare for natural disasters. Use classroom login for BrainPop Jr. Videos. Complete the Natural Disaster Chart as you learn from these websites and videos. First, watch the Earthquake Video Now scroll to page 5 of How to Prepare for Earthquakes. Next, watch the Flood Video Now scroll to page 4 of How to Prepare for Floods. Next, watch the Hurricane Video Now scroll ...

casey_piper

2012-04-05

91

Thermoacoustic natural gas liquefier  

Microsoft Academic Search

Cryenco and Los Alamos are collaborating to develop a natural-gas-powered natural-gas liquefier that will have no moving parts and require no electrical power. It will have useful efficiency, remarkable reliability, and low cost. The liquefaction of natural gas, which occurs at only 115 Kelvin at atmospheric pressure, has previously required rather sophisticated refrigeration machinery. The 1990 invention of the thermoacoustically

1997-01-01

92

TandEM: Titan and Enceladus mission  

USGS Publications Warehouse

TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (Montgolfi??re) and possibly several landing probes to be delivered through the atmosphere. ?? Springer Science + Business Media B.V. 2008.

Coustenis, A.; Atreya, S. K.; Balint, T.; Brown, R. H.; Dougherty, M. K.; Ferri, F.; Fulchignoni, M.; Gautier, D.; Gowen, R. A.; Griffith, C. A.; Gurvits, L. I.; Jaumann, R.; Langevin, Y.; Leese, M. R.; Lunine, J. I.; McKay, C. P.; Moussas, X.; Muller-Wodarg, I.; Neubauer, F.; Owen, T. C.; Raulin, F.; Sittler, E. C.; Sohl, F.; Sotin, C.; Tobie, G.; Tokano, T.; Turtle, E. P.; Wahlund, J. -E.; Waite, J. H.; Baines, K. H.; Blamont, J.; Coates, A. J.; Dandouras, I.; Krimigis, T.; Lellouch, E.; Lorenz, R. D.; Morse, A.; Porco, C. C.; Hirtzig, M.; Saur, J.; Spilker, T.; Zarnecki, J. C.; Choi, E.; Achilleos, N.; Amils, R.; Annan, P.; Atkinson, D. H.; Benilan, Y.; Bertucci, C.; Bezard, B.; Bjoraker, G. L.; Blanc, M.; Boireau, L.; Bouman, J.; Cabane, M.; Capria, M. T.; Chassefiere, E.; Coll, P.; Combes, M.; Cooper, J. F.; Coradini, A.; Crary, F.; Cravens, T.; Daglis, I. A.; de Angelis, E.; de Bergh, C.; de Pater, I.; Dunford, C.; Durry, G.; Dutuit, O.; Fairbrother, D.; Flasar, F. M.; Fortes, A. D.; Frampton, R.; Fujimoto, M.; Galand, M.; Grasset, O.; Grott, M.; Haltigin, T.; Herique, A.; Hersant, F.; Hussmann, H.; Ip, W.; Johnson, R.; Kallio, E.; Kempf, S.; Knapmeyer, M.; Kofman, W.; Koop, R.; Kostiuk, T.; Krupp, N.; Kuppers, M.; Lammer, H.; Lara, L. -M.; Lavvas, P.; Le, Mouelic, S.; Lebonnois, S.; Ledvina, S.; Li, J.; Livengood, T. A.; Lopes, R. M.; Lopez-Moreno, J. -J.; Luz, D.; Mahaffy, P. R.; Mall, U.; Martinez-Frias, J.; Marty, B.; McCord, T.; Salvan, C. M.; Milillo, A.; Mitchell, D. G.; Modolo, R.; Mousis, O.; Nakamura, M.; Neish, C. D.; Nixon, C. A.; Mvondo, D. N.; Orton, G.; Paetzold, M.; Pitman, J.; Pogrebenko, S.; Pollard, W.; Prieto-Ballesteros, O.; Rannou, P.; Reh, K.; Richter, L.; Robb, F. T.; Rodrigo, R.; Rodriguez, S.; Romani, P.; Bermejo, M. R.; Sarris, E. T.; Schenk, P.; Schmitt, B.; Schmitz, N.; Schulze-Makuch, D.; Schwingenschuh, K.; Selig, A.; Sicardy, B.; Soderblom, L.; Spilker, L. J.; Stam, D.; Steele, A.; Stephan, K.; Strobel, D. F.; Szego, K.; Szopa,

2009-01-01

93

The EM Earthquake Precursor  

NASA Astrophysics Data System (ADS)

Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two directional techniques were employed, resulting in three mapped, potential epicenters. The remaining, weaker signals presented similar directionality results to more epicentral locations. In addition, the directional results of the Timpson field tests lead to the design and construction of a third prototype antenna. In a laboratory setting, experiments were created to fail igneous rock types within a custom-designed Faraday Cage. An antenna emplaced within the cage detected EM emissions, which were both reproducible and distinct, and the laboratory results paralleled field results. With a viable system and continuous monitoring, a fracture cycle could be established and observed in real-time. Sequentially, field data would be reviewed quickly for assessment; thus, leading to a much improved earthquake forecasting capability. The EM precursor determined by this method may surpass all prior precursor claims, and the general public will finally receive long overdue forecasting.

Jones, K. B., II; Saxton, P. T.

2013-12-01

94

PREDICTION OF NATURAL DISASTERS  

Microsoft Academic Search

During the past 30 plus years, we have been dealing with several fundamental problems in prediction science. We believe that “the science of human natural disasters” (natural disasters affecting mankind) is not well addressed by the classical theory of dynamical systems. It is argued that there exist problems, when the theory of dynamic systems is used, related to (1) measurement

OuYANG SHOUCHENG; YI LIN; WU YONG

2000-01-01

95

Nature's Advice Book  

ERIC Educational Resources Information Center

What do can people learn from the world around them? Can a tree really teach something about life? Many times teachers provide students with facts about nature but fail to consider what one can learn from the natural world around them. After many months of exploring various ecosystems such as the prairie, rain forest, and desert, one of the…

Mahlin, Kathryn; Robertson, Amy

2005-01-01

96

Natural Hazards Review  

NSDL National Science Digital Library

The Natural Hazards Review is accessible from the American Society of Civil Engineers (ASCE). "Civil engineers, geologists, scientists and researchers involved in various aspects of construction will find the broad scope of the journal helpful for developing design strategies to mitigate natural hazards." ASCE non-members are required to complete an online form to access the articles.

2004-01-01

97

Geopolitics of natural gas  

SciTech Connect

This examines the role of gas in the world energy supply/demand. Special attention is paid to Western Europe, the Soviet Union, and the natural gas exporting countries. Forecasts of global energy demand until 2000 and data on Western Europe's proven natural gas reserves as per January 1982 are provided.

Russell, J.

1983-01-01

98

Adjusting to Natural Disasters  

Microsoft Academic Search

People can answer the risks presented by natural disasters in a number of ways; they canmove out of harms way, they can self protect, or they can insure. This paper uses the largest U.S. natural disaster on record, Hurricane Andrew, to evaluate how people and housing markets respond to a large disaster. Our analysis combines a unique ex post database

Kerry Smith; Jared C. Carbone; Daniel G. Hallstrom; Jaren C. Pope; Michael E. Darden

2005-01-01

99

CONNECTICUT NATURAL DIVERSITY DATABASE  

EPA Science Inventory

This is a statewide datalayer at 1:24,000 scale of general areas of concern with regards to state and federally listed Endangered, Threatened, and Special Concern species and significant natural communities. Locations of species and natural communities are based on data collecte...

100

Is That Natural?  

NSDL National Science Digital Library

Students will brainstorm ways that they use â and waste â natural resources. Also, they will respond to some facts about population growth and how people use petroleum. Lastly, students will consider the different ways that engineers interact with and use our natural resources.

Integrated Teaching And Learning Program

101

Modeling Natural Selection  

ERIC Educational Resources Information Center

In their research, scientists generate, test, and modify scientific models. These models can be shared with others and demonstrate a scientist's understanding of how the natural world works. Similarly, students can generate and modify models to gain a better understanding of the content, process, and nature of science (Kenyon, Schwarz, and Hug…

Bogiages, Christopher A.; Lotter, Christine

2011-01-01

102

Introduction to Exploring Nature  

ERIC Educational Resources Information Center

Children are fascinated with the world of nature. From the tiniest of seeds to the highest of birds, they wonder "Why?" "How?" and "What can I do with it?" This paper provides intriguing nature activities that provide a solid starting point for expanding children's thinking and learning. Through these activities, children will be building skills…

Early Childhood Today, 2006

2006-01-01

103

Design Inspired by Nature  

NSDL National Science Digital Library

Students discover how engineers can use biomimicry to enhance their designs. They learn how careful observation of nature â becoming a nature detective, so to speak â can lead to new innovations and products. In this activity, students reverse engineer a flower to glean design ideas for new products.

Integrated Teaching And Learning Program

104

Natural Language Processing.  

ERIC Educational Resources Information Center

Examines recent trends in research in natural language processing and discusses some applications of this research to the solution of information management problems. The article emphasizes that the importance of natural language processing systems is reflected in their frequent use in support of other computer programs. (71 references) (CK)

Rindflesch, Thomas C.

1996-01-01

105

Natural gas treatment  

Microsoft Academic Search

A novel, low-cost gas-treating unit developed by Gulf Oil Corp. is particularly suited to the removal of moisture and higher hydrocarbons from natural gas at many small fields where conventional methods would be too expensive. Natural gas, after mixing with antifreeze, is cooled at about pipeline pressure by countercurrent heat exchange with a refrigerant to condense higher boiling point hydrocarbons.

1978-01-01

106

Island Natural Science School.  

ERIC Educational Resources Information Center

Prepared for students in grade six attending the Island Natural Science School, Toronto, Ontario, Canada, this booklet offers information and suggests activities in the areas of ecology, conservation, natural resources, and outdoor recreation. Introductory material describes island lore, its formation and significant features, followed by units of…

Toronto Board of Education (Ontario).

107

Birds. Nature Discovery I.  

ERIC Educational Resources Information Center

The birds of New England and their particular habitats are explored in this guide which is part of a series of Nature Discovery publications. The materials are designed to directly supplement the natural science curricula and to complement other subject areas including social studies, language arts, music, and art. The program is designed for…

Stone, Sally F.

108

Human Natures, Nature Conservation, and Environmental Ethics  

Microsoft Academic Search

scientific community today about the global ecological sit-uation and the resultant need for nature conservation (e. g., NAS 1993, UCS 1993). Now is a time of unprecedented, es-calating, and well-documented environmental danger. There is general agreement among environmental scientists that the accelerating loss of biodiversity, populations (Hughes et al. 1997), species, and communities, should be a matter of great concern.

PAUL R. EHRLICH

2002-01-01

109

Unnaturalised racial naturalism.  

PubMed

Quayshawn Spencer (2014) misunderstands my treatment of racial naturalism. I argued that racial naturalism must entail a strong claim, such as "races are subspecies", if it is to be a substantive position that contrasts with anti-realism about biological race. My recognition that not all race naturalists make such a strong claim is evident throughout the article Spencer reviews (Hochman, 2013a). Spencer seems to agree with me that there are no human subspecies, and he endorses a weaker form of racial naturalism. However, he supports his preferred version of 'racial naturalism' with arguments that are not well described as 'naturalistic'. I argue that Spencer offers us an unnaturalised racial naturalism. PMID:24862687

Hochman, Adam

2014-06-01

110

Drawing on Nature  

NSDL National Science Digital Library

Awaken and sharpen your students' powers of observation by using art, particulary drawing, in your science classroom. There is a commonality between methods that artists employ in portraying their subjects and the methods that those studying nature employ in learning about the world, and this similarity can provide encouragement in leading science students to study nature via art. One way to achieve this objective is to have students create a Naturalist's Journal, as described in this article, where drawing is an essential part of a process to gather information from the natural world and to synthesize the field and lab experiences from class.

Dirnberger, Joe

2006-07-01

111

The Natural Inquirer  

NSDL National Science Digital Library

The Natural Inquirer is a science education resource journal to be used with learners ranging from Grade 5 and higher, with a focus on the secondary (grades 7-12) learner. It contains articles about natural resource research conducted by USDA Forest Service scientists. These are scientific journal articles that have been reformatted to meet the needs of audiences who are new to the area of science. The articles are easier to understand, shortened, more aesthetically pleasing to the eye, contain glossaries, and include hands-on activities. The goal of this magazine is to promote critical thinking, scientific inquiry, and investigation while learning about our natural resources and the environment.

112

Nature North Zine  

NSDL National Science Digital Library

Nature North Zine is a folksy, online magazine focused on the natural history of Manitoba and surrounding regions of North America. Site visitors can access sections for Spring, Summer, Fall, and Winter. The seasonal sections contain a variety of brief articles (from different dates) that address such subjects as wood frogs, native plant gardening, violets, snow snakes, and amphibians of Manitoba. The site also contains some very nice nature photographs in the Dragonflies of Manitoba and Images of Manitoba sections. Be sure not to miss the beautiful image of the Bohemian waxwing with a bright, red berry in its beak.

113

Against human nature  

Microsoft Academic Search

Against human nature\\u000a \\u000a Tim Ingold12 \\u000a \\u000a \\u000a \\u000a (12) \\u000a Department of Anthropology, University of Aberdeen, Aberdeen, Scotland, UK\\u000a \\u000a \\u000a Abstract\\u000a Are cultural differences superimposed upon a universal human nature? The appeal to an essentialist concept of human nature\\u000a is a defensive reaction to the legacy of racist science left by Darwin’s argument in The Descent of Man. Humans are made to appear different in degree

Tim Ingold

114

On nature's scaling effects  

NASA Astrophysics Data System (ADS)

This presentation afforded the opportunity to look back in the literature to discover scaling effects in nature that might be relevant to composites. Numerous examples were found in nature's approaches to wood, teeth, horns, leaves, eggs, feathers, etc. Nature transmits tensile forces rigidly with cohesive bonds, while dealing with compression forces usually through noncompressible hydraulics. The optimum design scaling approaches for aircraft were also reviewed for comparison with similitude laws. Finally, some historical evidence for the use of Weibull scaling in composites was reviewed.

Wilkins, Dick J.

1994-07-01

115

Natural Disaster Scenario Generator.  

National Technical Information Service (NTIS)

In this study, a computer system previously developed for generating nuclear damage scenarios (Dial-a-Scenario) was extended to produce natural disaster scenarios. The programs are implemented on both time-shared (remote terminal) and batch process modes....

J. Baca P. B. Bjorklund R. K. Laurino

1975-01-01

116

Immigration and Naturalization Statistics  

NSDL National Science Digital Library

The Immigration and Naturalizations Service Statistics site provides "comprehensive annual immigration statistics from 1994-1996, as well as state estimates of the United States' illegal alien resident and foreign-born populations."

Service., United S.

1997-01-01

117

The Nature of Intelligence.  

National Technical Information Service (NTIS)

This article discusses the nature of intelligence, introducing a new distinction between macrocomponents and microcomponents of human intelligence. Macrocomponents are the global-level constellations of processes that are formed from concatenations of mic...

R. J. Sternberg

1980-01-01

118

Natural gas monthly  

SciTech Connect

This document highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Data presented include volume and price, production, consumption, underground storage, and interstate pipeline activities.

NONE

1996-05-01

119

Make a Nature Trail  

ERIC Educational Resources Information Center

Discusses the planning, construction, use, and maintenance of a nature trail. Ideal for demonstrating interrelationships between plants and animals, conservation practices, wildlife management, plant succession, forestry, geologic features and other scientific phenomena. (JR)

Johnson, Janice K.

1973-01-01

120

Natural Aggregate: A Primer  

NSDL National Science Digital Library

This slide show provides an introduction to the production and uses of natural aggregate. Topics include some definitions, uses, and demand for aggregate. There is also information on its occurrence, mining, and production.

Langer, Bill

121

Is image steganography natural?  

PubMed

Steganography is the art of secret communication. Its purpose is to hide the presence of information, using, for example, images as covers. We experimentally investigate if stego-images, bearing a secret message, are statistically "natural." For this purpose, we use recent results on the statistics of natural images and investigate the effect of some popular steganography techniques. We found that these fundamental statistics of natural images are, in fact, generally altered by the hidden "nonnatural" information. Frequently, the change is consistently biased in a given direction. However, for the class of natural images considered, the change generally falls within the intrinsic variability of the statistics, and, thus, does not allow for reliable detection, unless knowledge of the data hiding process is taken into account. In the latter case, significant levels of detection are demonstrated. PMID:16370457

Martín, Alvaro; Sapiro, Guillermo; Seroussi, Gadiel

2005-12-01

122

Properties of Natural Zeolites.  

National Technical Information Service (NTIS)

Samples of the naturally occuring zeolites phillipsote, clinoptilolite, erionite, and chabazite have been surveyed for their gas adsorption, ion exchange, and other characteristics. Chabazite and erionite, which are generally more stable, also have higher...

R. A. Munson

1973-01-01

123

Tifft Farm Nature Preserve.  

ERIC Educational Resources Information Center

Described are the creation, development, activities, and programs of Tifft Farm, a 264-acre nature preserve and environmental education center in Buffalo, New York, constructed on a sanitary landfill. (BT)

Benjamin, Thomas B.; Gannon, David J.

1980-01-01

124

Natural Resources Defense Council  

NSDL National Science Digital Library

From the Natural Resources Defense Council, this website has the latest news from the Hill, plus information everyone needs on the state of our air, water, land and health. Initial contents include "State of Nature," a regular bulletin on environmental legislation; action guidelines; and findings on subjects ranging from children and environmental carcinogens to the pollution of U.S. coastal waters. Features in development include action alerts; consumer-oriented facts and FAQs; environmental multimedia clips; research tips; and more. The Natural Resources Defense Council is a national organization working in courtrooms, legislative chambers, regulatory agencies and the public arena to protect the world's natural resources and ensure a healthy environment for all.

1998-01-01

125

Natural Disasters in Florida  

NSDL National Science Digital Library

The students will translate the information they have gained into a poster/picture of Florida's natural disasters, label the storms, and list on the poster at least three safety practices to use with each storm.

Markham-Ahl, Claudia

2011-10-18

126

X-ray, Optical, and Radio Observations of SN 1999em and SN 1998S  

Microsoft Academic Search

Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first and only Type II-P detected at both X-ray

D. Pooley; W. H. G. Lewin; D. W. Fox; J. M. Miller; C. K. Lacey; S. D. Van Dyk; K. W. Weiler; R. A. Sramek; A. V. Filippenko; D. C. Leonard; S. Immler; R. A. Chevalier; A. C. Fabian; C. Fransson; K. Nomoto

2001-01-01

127

Naturally Occurring Polyesters  

Microsoft Academic Search

MAY I add to the recent note1 on the isolation of a natural elastic polyester2? The natural occurrence of polyesters was observed as early as 1908 by Boug-ault and Bourdier3, who showed that the waxes obtained by extraction of the leaves of a variety of conifers are linear polyesters of hydroxy-acids such as juniperic acid (omega-hydroxypalmitic acid) and sabinic acid

F. S. Spring

1945-01-01

128

USGS: Natural Hazards Gateway  

NSDL National Science Digital Library

This portal provides access to maps, data, and other information on the distribution and frequency of natural hazards in the United States. The material is arranged into seven categories: earthquakes, floods, hurricanes, landslides, tsunamis, volcanoes, and wildfires. There are also links to disaster emergency and relief organizations and to real-time resources such as RSS feeds, advisories, and the Natural Hazards Support System (NHSS), a system that enables users to monitor events as they occur anywhere on Earth.

129

USGS: Natural Hazards Gateway  

NSDL National Science Digital Library

This portal provides access to maps, data, and other information on the distribution and frequency of natural hazards in the United States. The material is arranged into seven categories: earthquakes, floods, hurricanes, landslides, tsunamis, volcanoes, and wildfires. There are also links to disaster emergency and relief organizations and to real-time resources such as RSS feeds, advisories, and the Natural Hazards Support System (NHSS), a system that enables users to monitor events as they occur anywhere on Earth.

2010-11-10

130

Natural hazard zonation  

USGS Publications Warehouse

This paper presents the basic scientific principles underpinning the professional practice of zonation for natural hazards such as floods, severe storms, earthquakes, volcanic eruptions, landslides, wildfires, tsunamis, and droughts. Zonation is the scientific process of identifying those parts of a geographic area which are best and least suited for community development in terms of their exposure to the physical effects of recurring, rapid onset, natural hazards.

Hays, Walter, W.

1996-01-01

131

Nature Web Focus: SARS  

NSDL National Science Digital Library

The journal Nature offers this free Web focus on Severe Acute Respiratory Syndrome (SARS), in which Nature's reporters pose key questions about the outbreak, and assess our preparedness to deal with future viral threats. Reader will find dozens of articles, including editorials, Science Updates, and Brief Communications from the journal. The articles trace the chronology of the SARS epidemic, and the section titled What Have We Learned? offers an excellent overview of what we know and what remains to be seen.

2007-12-12

132

Fossil Fuels: Natural Gas  

NSDL National Science Digital Library

This lesson provides an introduction to the use of natural gas as an energy source. Topics include its advantages (cleanliness, fewer carbon emissions), disadvantages (difficulty in transport and storage), sources, and usage. There is also a discussion of the creation and production of natural gas, the United States' production and reserves, and some potential new sources (coal bed methane, methane hydrates). The lesson includes an activity in which students investigate porosity and permeability in simulated sediments.

Pratte, John

133

Mining for Natural Resources  

NSDL National Science Digital Library

In this activity, students mine the chips from chocolate chip cookies. They weigh the cookies before and after mining, weigh the chips, and calculate the percent yield. This lab is designed to give students a better understanding of the processes involved in harvesting a natural resource and the impact it has on their environment and community. Analysis and conclusion questions focus on the fact that the mining of nonrenewable natural resources has a dramatic effect on our environment.

Obremski, Vince

134

NatureNews  

NSDL National Science Digital Library

NatureNews is the science news website of the journal Nature. The site provides a daily summary of news about research and discoveries in life, physical and applied sciences, and clinical medicine. Materials include a daily top story, featured stories, videos, a news blog, and event announcements. There are also longer format reports, opinion features, podcasts, and an archive of past issues organized by year and month.

135

NatureWorks  

NSDL National Science Digital Library

Developed by New Hampshire Public Television and the Squam Lakes Natural Science Center, NatureWorks offers teachers an excellent resource for biologically related subjects geared for students grades 3-6. Sixteen topics are included, ranging from species diversity to fresh water communities. Each subject has a one page description for students to read and a short quiz for them to take. A teacher's guide offers additional vocabulary, hands-on activities, teaching tips, and external links.

2000-01-01

136

Natural Resources Canada  

NSDL National Science Digital Library

This website is home to Natural Resources Canada (NRCan), a government agency dealing with natural resource issues important to Canadians. It covers energy, climate change, earthquakes, geography, geology, floods, landslides, minerals and metals, forest fires, mining, remote sensing, and forestry. This site links to numerous government agencies, including the Geological Survey of Canada, Canadian Forest Service, and the Office of Energy. Also offered are a Kid's page with activities, information for teachers, and links to maps, databases, publications, and library resources.

137

Natural Building Project  

NSDL National Science Digital Library

This document provides a basic outline for a high-school level natural building course taught by Robert Morgan of Open Meadow High School. The main goal of the course was to introduce students to natural building and construction methods. The course's objectives, class activities, suggested materials and research projects are outlined. A summary of a field trip activity is also included. This document may be downloaded in Microsoft Word Doc file format.

Morgan, Robert

2011-11-28

138

An Adaptive Algorithm for Text Detection from Natural Scenes  

Microsoft Academic Search

We present a new adaptive algorithm for automatic detection of text from a natural scene. The initial cues of text regions are first detected from the captured image\\/video. An adaptive color modeling and searching algorithm is then utilized near the initial text cues, to discriminate text\\/non-text regions. EM optimization algorithm is used for color modeling, under the constraint of text

Jiang Gao; Jie Yang

2001-01-01

139

The Human Relation With Nature and Technological Nature  

Microsoft Academic Search

Two world trends are powerfully reshaping human existence: the degradation, if not destruction, of large parts of the natural world, and unprecedented technological development. At the nexus of these two trends lies technological nature—technologies that in various ways mediate, augment, or simulate the natural world. Current examples of technological nature include videos and live webcams of nature, robot animals, and

Peter H. Kahn; Rachel L. Severson; Jolina H. Ruckert

2009-01-01

140

How Nature Helps Children Develop.  

ERIC Educational Resources Information Center

Argues that children need contact with nature to grow well. Suggests that nature stimulates powers of observation, creativity, and a sense of peace. Recommends the protection of nature, adult guidance of children with nature, and poetry that expresses a child's connection to nature, citing several studies concerned with environment and children.…

Crain, William

1997-01-01

141

Enhance Nature Exploration with Technology  

ERIC Educational Resources Information Center

Kids and nature seem like a natural combination, but what was natural a generation ago is different today. Children are spending less time outdoors but continue to need nature for their physical, emotional, and mental development. This fact has led author Richard Louv to suggest that today's children are suffering from "nature-deficit disorder"…

Holloway, Patricia; Mahan, Carol

2012-01-01

142

EMS adaptation for climate change  

NASA Astrophysics Data System (ADS)

The purpose of this study was to find an appropriate scenario of pre-hospital transportation of an emergency medical service (EMS) system for burdensome casualties resulting from extreme climate events. A case of natural catastrophic events in Taiwan, 88 wind-caused disasters, was reviewed and analyzed. A sequential-conveyance method was designed to shorten the casualty transportation time and to promote the efficiency of ambulance services. A proposed mobile emergency medical center was first constructed in a safe area, but nearby the disaster area. The Center consists of professional medical personnel who process the triage of incoming patients and take care of casualties with minor injuries. Ambulances in the Center were ready to sequentially convey the casualties with severer conditions to an assigned hospital that is distant from the disaster area for further treatment. The study suggests that if we could construct a spacious and well-equipped mobile emergency medical center, only a small portion of casualties would need to be transferred to distant hospitals. This would reduce the over-crowding problem in hospital ERs. First-line ambulances only reciprocated between the mobile emergency medical center and the disaster area, saving time and shortening the working distances. Second-line ambulances were highly regulated between the mobile emergency medical center and requested hospitals. The ambulance service of the sequential-conveyance method was found to be more efficient than the conventional method and was concluded to be more profitable and reasonable on paper in adapting to climate change. Therefore, additional practical work should be launched to collect more precise quantitative data.

Pan, C.; Chang, Y.; Wen, J.; Tsai, M.

2010-12-01

143

Reinventing Natural Selection  

NASA Astrophysics Data System (ADS)

Although many research studies report students’ Lamarckian misconceptions, only a few studies present learning and teaching strategies that focus on the successful development of the concept of natural selection. The learning and teaching strategy for upper secondary students (aged 15 16) presented in this study conducted in The Netherlands is based on the idea of guided reinvention, rather than on the conceptual change strategy. In guided reinvention, students reinvent the concept of natural selection by answering a sequence of questions based on the logical nature of Darwin’s theory. The results show that few Lamarckian explanations for evolution were recorded in the study and that the majority of the students developed a Darwinian or neo-Darwinian conception. The status of Lamarckian misconceptions is challenged.

Geraedts, Caspar L.; Boersma, Kerst Th.

2006-06-01

144

Natural history of cirrhosis.  

PubMed

Significant strides have been made in the last few years in advancing our knowledge of the natural history of cirrhosis. These include (1) a better understanding of prognosis in compensated and decompensated cirrhosis, (2) improved estimates of the natural course of variceal bleeding in patients receiving standard of care therapy, (3) recognition of renal failure and infection as important determinants of mortality in the clinic course, (4) realization of the importance of hepatic venous pressure gradient as a marker of prognosis, progression, and treatment response, and (5) evolution of noninvasive studies of liver stiffness as potential predictors of decompensation. Further studies identifying cirrhotics at highest risk of transitioning from a compensated state to a decompensated state will be important in order to alter the natural history of cirrhosis. PMID:23314828

Asrani, Sumeet K; Kamath, Patrick S

2013-02-01

145

Arkansas Natural Resources Commission  

NSDL National Science Digital Library

In 1937, the Arkansas General Assembly enacted the nation's first conservation district law. Since that time, the state has grown to create entities like the Arkansas Natural Resources Commission to help protect its various natural resources. On this site, visitors can look through seven different sections, including Water Development, Conservation, and Arkansas Water Plan. Within each of these sections, visitors can look through a range of working papers, conservation documents, and online GIS data sets based on state-wide natural resource surveys. Moving on, the News & Publications features video blog posts, updates about conservation programs, and more. The Rules area is another helpful section of the site, providing a wide range of current rules created by the Commission to govern Arkansas wetlands, tax credits, groundwater management, and poultry management.

146

Monitored natural attenuation.  

PubMed

Monitored natural attenuation (MNA) is an in situ remediation technology that relies on naturally occurring and demonstrable processes in soil and groundwater which reduce the mass and concentration of the contaminants. Natural attenuation (NA) involves both aerobic and anaerobic degradation of the contaminants due to the fact that oxygen is used up near the core of the contaminant plume. The aerobic and anaerobic microbial processes can be assessed by microbial activity measurements and molecular biology methods in combination with chemical analyses. The sampling and knowledge on the site conditions are of major importance for the linkage of the results obtained to the conditions in situ. Rates obtained from activity measurements can, with certain limitations, be used in modeling of the fate of contaminants whereas most molecular methods mainly give qualitative information on the microbial community and gene abundances. However, molecular biology methods are fast and describe the in situ communities and avoid the biases inherent to activity assays requiring laboratory incubations. PMID:19882289

Jørgensen, Kirsten S; Salminen, Jani M; Björklöf, Katarina

2010-01-01

147

Multi-natural inflation  

NASA Astrophysics Data System (ADS)

We propose a multi-natural inflation model in which the single-field inflaton potential consists of two or more sinusoidal potentials that are comparable in size but have different periodicity with a possible non-zero relative phase. The model is versatile enough to realize both large-field and small-field inflation. We show that, in a model with two sinusoidal potentials, the predicted values of the spectral index and tensor-to-scalar ratio lie within the 1? region of the Planck data. In particular, there is no lower bound on the decay constants in contrast to the original natural inflation. We also show that, in a certain limit, multi-natural inflation can be approximated by a hilltop quartic inflation model.

Czerny, Michael; Takahashi, Fuminobu

2014-06-01

148

Lamarck and Natural Selection  

NSDL National Science Digital Library

Charles Darwin defined natural selection in "On the Origin of Species," however, Darwin did not invent the idea of evolution and not everyone saw his ideas as original. The shadow of Lamarckian theory which Darwin wanted desperately to escape is a genuine scientific precursor and what has become known as the Lamarckian Heresy has maintained a presence on the fringes of biology to this day. This radio broadcast explores who Lamarck was, how natural selection escaped from his shadow and gained acceptance from the scientific establishment, and whether any evidence has emerged that might challenge the elegant simplicity of natural selection. There is discussion about whether what is passed on to descendants may be affected by experience and environment; the experiments performed by Mendel that led to genetics; the role of DNA, gene mutations, and networks of genes in epigenetics; and how there seem to be fewer genes in humans than expected. The 2003 broadcast is 57 minutes in length.

2007-05-06

149

Forces of Nature  

NSDL National Science Digital Library

These interactive simulations allow students to investigate four of nature's more violent phenomena: volcanoes, earthquakes, hurricanes, and tornadoes. Each simulation begins with a brief written tutorial describing the characteristics and destructive potential of these hazards. Users may then adjust the various factors affecting the occurence of these phenomena (for instance, ocean temperature, humidity, and atmospheric pressure for hurricanes) and observe the results. These simulations are related to the film National Geogrpahic film Forces of Nature ; other links provide access to lesson plans designed to accompany the film and to a list of locations where the film can be seen. There are also links to a preview of the film, fast facts, stories about famous natural disasters, and a glossary.

2007-12-12

150

Identified EM Earthquake Precursors  

NASA Astrophysics Data System (ADS)

Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After a number of custom rock experiments, two hypotheses were formed which could answer the EM wave model. The first hypothesis concerned a sufficient and continuous electron movement either by surface or penetrative flow, and the second regarded a novel approach to radio transmission. Electron flow along fracture surfaces was determined to be inadequate in creating strong EM fields, because rock has a very high electrical resistance making it a high quality insulator. Penetrative flow could not be corroborated as well, because it was discovered that rock was absorbing and confining electrons to a very thin skin depth. Radio wave transmission and detection worked with every single test administered. This hypothesis was reviewed for propagating, long-wave generation with sufficient amplitude, and the capability of penetrating solid rock. Additionally, fracture spaces, either air or ion-filled, can facilitate this concept from great depths and allow for surficial detection. A few propagating precursor signals have been detected in the field occurring with associated phases using custom-built loop antennae. Field testing was conducted in Southern California from 2006-2011, and outside the NE Texas town of Timpson in February, 2013. The antennae have mobility and observations were noted for recurrence, duration, and frequency response. At the Southern California field sites, one loop antenna was positioned for omni-directional reception and also detected a strong First Schumann Resonance; however, additional Schumann Resonances were absent. At the Timpson, TX field sites, loop antennae were positioned for directional reception, due to earthquake-induced, hydraulic fracturing activity currently conducted by the oil and gas industry. Two strong signals, one moderately strong signal, and approximately 6-8 weaker signals were detected in the immediate vicinity. The three stronger signals were mapped by a biangulation technique, followed by a triangulation technique for confirmation. This was the first antenna mapping technique ever performed for determining possible earthquake epicenters. Six and a half months later, Timpson experienced two M4 (M4.1 and M4.3) earthquakes on September 2, 2013 followed by a M2.4 earthquake three days later, all occurring at a depth of five kilometers. The Timpson earthquake activity now has a cyclical rate and a forecast was given to the proper authorities. As a result, the Southern California and Timpson, TX field results led to an improved design and construction of a third prototype antenna. With a loop antenna array, a viable communication system, and continuous monitoring, a full fracture cycle can be established and observed in real-time. In addition, field data could be reviewed quickly for assessment and lead to a much more improved earthquake forecasting capability. The EM precursors determined by this method appear to surpass all prior precursor claims, and the general public will finally receive long overdue forecasting.

Jones, Kenneth, II; Saxton, Patrick

2014-05-01

151

SIGNIFICANT NATURAL HERITAGE AREAS (NC)  

EPA Science Inventory

The North Carolina Department of Environment and Natural Resources, Division of Parks and Recreation, Natural Heritage Program in cooperation with the NC Center for Geographic Information & Analysis, developed the Significant Natural Heritage Areas digital data to determine the a...

152

Building natural gas locomotives  

SciTech Connect

This article describes a liquefied natural gas-fueled locomotive built by Morrison Knudsen which includes a Caterpillar 1200-horsepower V-16, a monofuel management system with double-wall super-insulated cryogenic tanks, and microprocessor-based controls. Efforts by railroad companies to reduce operating costs and meet future emissions standards have led engineers to look for innovative ways to design trains. In January, Morrison Knudsen Corp. of Boise, Idaho, powered its way into the locomotive manufacturing business when it introduced the natural gas-fueled MK1200G, to be used mostly around railroad company yards and on trips shorter than 50 miles.

O'Conner, L.

1994-04-01

153

Nature: The Mouse Genome  

NSDL National Science Digital Library

This Web site from the journal Nature offers a one-stop online resource for information on the mouse genome -- "the experimental key to the human genome." Visitors have free access to all content from the journal's special mouse genome issue. Web features include an interactive timeline detailing the history of the mouse in genetics, related news articles and commentary, Web links, and more. Scientific papers and letters to Nature are also available for those who would like to delve into the subject at depth. Additionally, the site provides a selection of classic research papers free to registered users until March 5, 2003.

2003-01-01

154

Natural language processing.  

PubMed

Natural language processing (NLP) is the study of mathematical and computational modeling of various aspects of language and the development of a wide range of systems. These include spoken language systems that integrate speech and natural language; cooperative interfaces to databases and knowledge bases that model aspects of human-human interaction; multilingual interfaces; machine translation; and message-understanding systems, among others. Research in NLP is highly interdisciplinary, involving concepts in computer science, linguistics, logic, and psychology. NLP has a special role in computer science because many aspects of the field deal with linguistic features of computation and NLP seeks to model language computationally. PMID:17831443

Joshi, A K

1991-09-13

155

Internet for Nature  

NSDL National Science Digital Library

This Web site contains a free tutorial on how to effectively mine the Internet for natural sciences info. This interactive tutorial is one of many created by the University of Bristol's Resource Discover Network (RDN). The tutorial starts with a tour of the types of Internet resources available for researching the natural world, followed by a lesson on tools used to locate these resources (like search engines and Web portals). The tutorial also includes a helpful section on how to critically evaluate Web content. Users can follow a link to access a number of other science-related tutorials -- part of the RDN Virtual Training Suite.

156

Sustainable Natural Resource Engineering  

NSDL National Science Digital Library

Natural Resources figure centrally in the understanding of Sustainability and the Professional responsibility of engineers. A teaching approach is outlined that a) utilizes standard Engineering preparation in applied mathematics; b) applies it as a unifying theme across the natural resource field; c) embeds basic undergraduate exposure to ecological and economic concepts; and d) operates via desktop simulation tools accessible to all university students. The approach suggested is related to the new American Society of Civil Engineers (ASCE) Body of Knowledge (BOK2) requirement of Sustainability.

Lynch, Daniel

2009-09-08

157

Natural environment analysis  

NASA Technical Reports Server (NTRS)

The influence of terrain features on wind loading of the space shuttle while on the launch pad, or during early liftoff, was investigated both qualitatively and quantitatively. The climatology and meteorology producing macroscale wind patterns and characteristics for the Vandenburg Air Force Base launch site are described. Field test data are analyzed, and the nature and characteristic of flow disturbances due to the various terrain features, both natural and man-made, are reviewed. The magnitude of these wind loads are estimated. Finally, effects of turbulence are discussed. It is concluded that the influence of complex terrain can create significant wind loading on the vehicle.

Frost, W.

1985-01-01

158

Interfering with nature.  

PubMed

Certain kinds of medical treatment are often held to be morally unacceptable because they are an 'interference with nature'. I suggest a way in which we can make sense of such ideas. We can make significant choices only against a background of conditions which we regard as 'natural', and these will typically include such facts as those of birth and death, of youth and age, and of sexual relations. I argue, however, that such ideas, though intelligible, do not establish any valid moral objection to, for instance, the use of ovarian tissue for assisted conception. PMID:12599343

Norman, R

1996-01-01

159

Introduction to Natural Selection  

NSDL National Science Digital Library

This lesson will help students develop an understanding of natural selection, specifically, how it unfolds from generation to generation. The Motivation section introduces a species of bird that became (over millions of years) numerous species, through adaptation. The Development section is a hands-on activity that demonstrates how populations change little by little, generation by generation, due to survival of species that have traits that are beneficial in an environment. Students will learn why organisms evolve over time, how natural selection works, and how certain factors determine survival and differences in organisms.

160

Nature: The Human Genome  

NSDL National Science Digital Library

This special Web Focus from the journal Nature presents research papers that "serve as the definitive historical record for the sequences and analyses of human chromosomes -- the ultimate results of the Human Genome Project." Papers are available for chromosomes 6, 7, 14, 20, 21, 22, and Y, which readers can access (no subscription required) by clicking on the image of the corresponding chromosome. The papers for chromosome 6 are the most recent, published in the October 23, 2003 issue of Nature. The website also offers free feature articles on the subject.

2008-07-31

161

Natural radioactivity in water supplies  

SciTech Connect

This book outlines the scientific aspects of the control of natural radioactivity in water supplies, as well as the labyrinthine uncertainties in water quality regulation concerning natural radiocontamination of water. The author provides an introduction to the theory of natural radioactivity; addresses risk assessment, sources of natural radiocontamination of water, radiobiology of natural radioactivity in water, and federal water law concerning natural radiocontamination; and presents an account of how one city dealt with the perplexities that mark this area of water quality regulation.

Horner, J.K.

1985-01-01

162

About the nature of the coherence of light waves  

NASA Astrophysics Data System (ADS)

The nature of electromagnetic (EM) phenomena, including light, is not fully clear. Postulated rejection of EM ether as a hypothetical habitat and distribution of EM waves, holds in the uncertainty and the problem of understanding the existence of most of these waves, because the notion of "wave" inseparable from the concept of "environment". EM ether, as a hypothetical environment of origin and propagation of EM waves, was declined by postulate. This keeps the uncertainty in the problem of understanding the existence of these waves actually, since the definition of "wave" is an part of the definition of "environment". The input in physics of the concept of wave "coherence", which was necessary to explain the phenomenon of interference of light, also requires a transparent physical interpretation. Today use of the idea of the several-meters - length wave zugs, which are emitted by individual atoms, is at least unconvincing, thus there is technical ability to generate powerful light pulses of 10-15 s. A quantum model of the structure of the optical packet stream, which provides a transparent physical interpretation of all parameters of coherent light, is offered. In this model parameters of coherence are organically linked with the geometry parameters of the quantum packets. Developments of classical wave optics will not be discarded. To coordinate with the quantum-packet model and modern views about the nature of light, we either give them a new interpretation or adjust, or develop these developments. In particular, a new interpretation of the experimental fact increase the radius of coherence of light coming from distant sources (stars) is offered. Modern conception of light corpuscles-photons is formulated. The estimations of the size of the spatial localization of the photon is received. "Diffraction of photons" is considered.

Demyanenko, Petro O.; Demianenko, Kostiantyn P.; Demianenko, Fedir P.; Zinkovskiy, Yuri F.

2011-09-01

163

Natural and accelerated bioremediation research program plan  

SciTech Connect

This draft plan describes a ten-year program to develop the scientific understanding needed to harness and develop natural and enhanced biogeochemical processes to bioremediate contaminated soils, sediments and groundwater at DOE facilities. The Office of Health and Environmental Research (OHER) developed this program plan, with advice and assistance from DOE`s Office of Environmental Management (EM). The program builds on OHER`s tradition of sponsoring fundamental research in the life and environmental sciences and was motivated by OHER`s and Office of Energy Research`s (OER`s) commitment to supporting DOE`s environmental management mission and the belief that bioremediation is an important part of the solution to DOE`s environmental problems.

NONE

1995-09-01

164

Natural Resources: Stargazing  

NSDL National Science Digital Library

In 2009, we had the year of astronomy. Even President Obama hosted an astronomy night on the White House lawn. Your explorations of nature need not be limited to daylight hours--though it is important to point our when celestial objects like the Moon are v

Mayes, Valynda

2010-03-01

165

Nature in the City  

NSDL National Science Digital Library

Nature in the City is a project of the Earth Island Institute, and is "wholly dedicated to ecological conservation, restoration and stewardship of the [San] Franciscan bioregion." Their website's "About" section gives a thorough explanation of not only their goals, as well as a definition of nature. Furthermore, this section provides some philosophical insight into what exactly "urban nature" happens to be. Those visitors interested in a more visceral tour of San Francisco should check out the "Photo Gallery" link, and they should be sure to check out the "Natural Areas" album to view some eerie-looking oak woodlands in Golden Gate Park. Additionally, visitors to the site who are interested in the life that teems on Alcatraz Island will enjoy file number fourteen which includes an image of roosting double-crested cormorants on a dramatic hillside. Finally the "Local Ecology" link has an explanation of the "Biodiversity Crisis" in San Francisco, which can be attributed to ecological, political, institutional, social and cultural factors.

166

Natural Language Interface  

NSDL National Science Digital Library

This case study, by David M. Lane of Rice University, assesses the question, "Is it easier to learn to use computer software that uses natural language commands?" Main concepts are analysis of covariance, adjusted means, and boxplots. The experimental design, descriptive statistics, inferential statistics, and raw data are all given.

Lane, David M.

2009-02-05

167

POTENTIAL NATURAL VEGETATION COVERAGE  

EPA Science Inventory

"Potential natural vegetation is defined as the vegetation that would exist today if humans were removed from the scene and if the plant succession after their removal were telescoped into a single moment. The time compression eliminates the effects of future climatic fluc...

168

The Natural Learning Process  

ERIC Educational Resources Information Center

Teacher-educator and researcher Daniel L. Kohut suggests in "Musical Performance: Learning Theory and Pedagogy" that there are many problems that result from the way music teachers often teach. Most teachers focus on the process, not the goal. The Natural Learning Process that Kohut advocates is the same process that young children use when they…

Criss, Ellen

2008-01-01

169

Criteria for natural hierarchies  

NASA Astrophysics Data System (ADS)

With the discovery of a particle that seems rather consistent with the minimal Standard Model Higgs boson, attention turns to questions of naturalness, fine-tuning, and what they imply for physics beyond the Standard Model and its discovery prospects at run II of the LHC. In this article we revisit the issue of naturalness, discussing some implicit assumptions that underly some of the most common statements, which tend to assign physical significance to certain regularization procedures. Vague arguments concerning fine-tuning can lead to conclusions that are too strong and perhaps not as generic as one would hope. Instead, we explore a more pragmatic definition of the hierarchy problem that does not rely on peeking beyond the murky boundaries of quantum field theory: we investigate the fine-tuning of the electroweak scale associated with thresholds from heavy particles, which is both calculable and dependent on the nature of the would-be ultraviolet completion of the Standard Model. We discuss different manifestations of new high-energy scales that are favored by experimental hints for new physics with an eye toward making use of fine-tuning in order to determine natural regions of the new physics parameter spaces.

de Gouvêa, André; Hernández, Daniel; Tait, Tim M. P.

2014-06-01

170

Natural or Artificial  

NSDL National Science Digital Library

This worksheet, suitable for pre-readers, directs students to categorize pictures as sources of either natural or artificial light. The resource is part of the teacher's guide accompanying the video, NASA Why Files: The Case of the Mysterious Red Light. Lesson objectives supported by the video, additional resources, teaching tips and an answer sheet are included in the teacher's guide.

171

The Nature of Diamonds  

NASA Astrophysics Data System (ADS)

The paragon of physical perfection and a sparkling example of Earth's forces at work, the diamond has fascinated all realms of society, from starlets to scientists. The Nature of Diamonds is a comprehensive look at nature's most coveted gem. A handsome, large-format book, The Nature of Diamonds is an authoritative and richly-illustrated tribute to the diamond. Leading geologists, gemologists, physicists, and cultural observers cover every facet of the stone, from its formation in the depths of the Earth, its ascent to the surface, and its economic, regal, social, and technological roles. Cutting-edge research takes the reader to the frontiers of diamond exploration and exploitation, from the Arctic wastes to the laboratories where diamonds are created for massive road shredders that rip up and then re-create superhighways. Here also is an overview of cutting, from the rough stones in Roman rings to the highly-faceted stones we see today, and a glimpse into the business of diamonds. Finally, The Nature of Diamonds chronicles scientific and cultural history and explores the diamond as both a sacred and a social symbol, including a picture history of betrothal rings. Wide-ranging illustrations explain the geology of diamonds, chart the history of mining from its origins in India and Brazil through the diamond rush in South Africa and today's high-tech enterprises, and capture the brilliance and beauty of this extraordinary gem. _

Harlow, George E.

1997-10-01

172

Natural Radioactivity in Bananas  

Microsoft Academic Search

The content of 40K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, São Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil

V. A. B. Zagatto; N. H. Medina; E. Okuno; N. K. Umisedo

2008-01-01

173

Natural Radioactivity in Bananas  

Microsoft Academic Search

The content of 40K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, Sa~o Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil

V. A. B. Zagatto; N. H. Medina; E. Okuno; N. K. Umisedo

2008-01-01

174

A Natural Integration  

ERIC Educational Resources Information Center

A five-week study taught students how to write a field guide that identified the plants in a small wooded area they passed through on their way to their school playground. By creating this authentic genre of science writing, students came to understand and care for the natural world in their immediate environment. They also developed important…

Coskie, Tracy; Hornof, Michelle; Trudel, Heidi

2007-01-01

175

The Nature of Atoms.  

ERIC Educational Resources Information Center

This monograph was written for the purpose of presenting physics to college students who are not preparing for careers in physics. It deals with the nature of atoms, and treats the following topics: (1) the atomic hypothesis, (2) the chemical elements, (3) models of an atom, (4) a particle in a one-dimensional well, (5) a particle in a central…

Holden, Alan

176

The Nature of Evolution  

ERIC Educational Resources Information Center

The nature of evolution, the historical change in the universe, and the change that is caused by the workings of the dynamic processes at the smallest and largest scales are studied. It is viewed that the cumulative change in the historical systems is caused by evolution, which is a type of causal relationship and evolutionary processes could be…

Alles, David L.

2005-01-01

177

Geopolitics of natural gas  

SciTech Connect

With almost as many vital economic interests as there were attendees, two natural gas international conferences were held in North America during September and October, to share experience and forecasts. On September 26, the Canadian Energy Research Institute (CERI) and the Calgary Chamber of Commerce sponsored the International Gas Markets Conference and drew 400 persons. And on October 5-6, at the University of Colorado at Boulder, USA, the International Research Center for Energy and Economic Development (ICEED) held its Tenth International Energy Conference on Economic and Political Issues of Natural Gas in International Trade, drawing some 200 experts. The latter seminar was preceded by a two-day seminar on Asian Energy Supplies and Requirements, which also featured natural gas in many of its presentations. To provide an overview of some of these pressing questions, Energy Detente reports on these two comprehensive seminars on natural gas. This issue also presents the fuel price/tax series and the principal industrial fuel prices for the Eastern Hemisphere for November 1983.

Not Available

1983-11-09

178

Designing Nature's Way  

ERIC Educational Resources Information Center

In the case of cars and other engineered objects, humans go about the design process in a very intentional way. They pretty much know what they are aiming for. The activity described in this article demonstrates how a computer can simulate biological evolution and the laws of natural selection. The article is divided into the following sections:…

Fisher, Diane

2005-01-01

179

Natural Sciences Image Library  

NSDL National Science Digital Library

This collection specializes in New Zealand natural science images that are of scientific and/or 'technological' interest and importance. The images are searchable by taxonomy or by theme.This library is growing and the breadth of coverage increasing. To ensure the collection remains dynamic and relevant, images are being added and retired weekly.

Library, Natural S.

2010-02-16

180

Natural fracture systems studies  

SciTech Connect

The objectives of this program are (1) to develop a basinal-analysis methodology for natural fracture exploration and exploitation, and (2) to determine the important characteristics of natural fracture systems for use in completion, stimulation, and production operations. Natural-fracture basinal analysis begins with studies of fractures in outcrop, core and logs in order to determine the type of fracturing and the relationship of the fractures to the lithologic environment. Of particular interest are the regional fracture systems that are pervasive in western US tight sand basins. A Methodology for applying this analysis is being developed, with the goal of providing a structure for rationally characterizing natural fracture systems basin-wide. Such basin-wide characterizations can then be expanded and supplemented locally, at sites where production may be favorable. Initial application of this analysis is to the Piceance basin where there is a wealth of data from the Multiwell Experiment (MWX), DOE cooperative wells, and other basin studies conducted by Sandia, CER Corporation, and the USGS (Lorenz and Finley, 1989, Lorenz et aI., 1989, and Spencer and Keighin, 1984). Such a basinal approach has been capable of explaining the fracture characteristics found throughout the southern part of the Piceance basin and along the Grand Hogback.

Lorenz, J.C.; Warpinski, N.R.

1992-09-01

181

The Nature of Diamonds  

NSDL National Science Digital Library

This Web site looks at how diamonds are created (naturally and synthetically), and how they have been used throughout history. It contains information on composition and structure, the origins and history of diamonds, mining & distribution and an overview of the many uses of diamonds and how they are grown synthetically. A bibliography provides a listing of more than 75 resources for further study.

182

Picturing the Natural World  

ERIC Educational Resources Information Center

How is the natural environment in the neighborhood representative of the larger biosphere in which people live? Studying the local birds and flora of the Pacific Northwest in the context of the local parks and ponds provided a rich opportunity for third-grade students at St. Thomas School in Medina, Washington, to explore and learn about…

Salia, Hannah

2011-01-01

183

Natural Gas Hydrates  

Microsoft Academic Search

This paper reports on gas clathrates (commonly called hydrates), which are crystalline compounds that occur when water form a cage-like structure around smaller guest molecules. Gas hydrates of interest to the natural gas hydrocarbon industry are composed of water and eight molecules: methane, ethane, propane, isobutane, normal butane, nitrogen, carbon dioxide, and hydrogen sulfide. Hydrate formation is possible in any

E. Sloan Jr.; E. D. Jr

1991-01-01

184

Reinventing Natural Selection  

ERIC Educational Resources Information Center

Although many research studies report students' Lamarckian misconceptions, only a few studies present learning and teaching strategies that focus on the successful development of the concept of natural selection. The learning and teaching strategy for upper secondary students (aged 15-16) presented in this study conducted in The Netherlands is…

Geraedts, Caspar L.; Boersma, Kerst Th.

2006-01-01

185

Nature in the City.  

ERIC Educational Resources Information Center

Presents three science activities targeted to help urban students learn about nature: (1) observing coloration patterns of pigeons; (2) measuring local rainfall and comparing it to other areas; and (3) conducting a biodiversity study by observing a patch of lawn. (YDS)

Melber, Leah W.

2000-01-01

186

Analyses of Natural Gases.  

National Technical Information Service (NTIS)

The tape file contains routine analyses and related data for 11,305 natural gas samples. These samples were collected as a part of a continuous survey of the free world for occurrences of helium. This survey has been conducted in the United States by the ...

L. Moffitt I. Plunkett P. Anderson

1977-01-01

187

Radioactivity: A Natural Phenomenon.  

ERIC Educational Resources Information Center

Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

Ronneau, C.

1990-01-01

188

A Natural Hazards Workbook.  

ERIC Educational Resources Information Center

This paper discusses the development of and provides examples of exercises from a student workbook for a college-level course about natural hazards. The course is offered once a year to undergraduates at Western Illinois University. Students are introduced to 10 hazards (eight meteorological plus earthquakes and volcanoes) through slides, movies,…

Kohler, Fred

189

Natural hazards science strategy  

USGS Publications Warehouse

The mission of the U.S. Geological Survey (USGS) in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. USGS scientific research - founded on detailed observations and improved understanding of the responsible physical processes - can help to understand and reduce natural hazard risks and to make and effectively communicate reliable statements about hazard characteristics, such as frequency, magnitude, extent, onset, consequences, and where possible, the time of future events. To accomplish its broad hazard mission, the USGS maintains an expert workforce of scientists and technicians in the earth sciences, hydrology, biology, geography, social and behavioral sciences, and other fields, and engages cooperatively with numerous agencies, research institutions, and organizations in the public and private sectors, across the Nation and around the world. The scientific expertise required to accomplish the USGS mission in natural hazards includes a wide range of disciplines that this report refers to, in aggregate, as hazard science. In October 2010, the Natural Hazards Science Strategy Planning Team (H-SSPT) was charged with developing a long-term (10-year) Science Strategy for the USGS mission in natural hazards. This report fulfills that charge, with a document hereinafter referred to as the Strategy, to provide scientific observations, analyses, and research that are critical for the Nation to become more resilient to natural hazards. Science provides the information that decisionmakers need to determine whether risk management activities are worthwhile. Moreover, as the agency with the perspective of geologic time, the USGS is uniquely positioned to extend the collective experience of society to prepare for events outside current memory. The USGS has critical statutory and nonstatutory roles regarding floods, earthquakes, tsunamis, landslides, coastal erosion, volcanic eruptions, wildfires, and magnetic storms - the hazards considered in this plan. There are numerous other hazards of societal importance that are considered either only peripherally or not at all in this Strategy because they are either in another of the USGS strategic science plans (such as drought) or not in the overall mission of the USGS (such as tornados).

Holmes, Robert R., Jr.; Jones, Lucile M.; Eidenshink, Jeffery C.; Godt, Jonathan W.; Kirby, Stephen H.; Love, Jeffrey J.; Neal, Christina A.; Plant, Nathaniel G.; Plunkett, Michael L.; Weaver, Craig S.; Wein, Anne; Perry, Suzanne C.

2012-01-01

190

QUALIDADE AMBIENTAL (?) EM ÁREAS DE EXPANSÃO URBANA: UM ESTUDO DE CASO SOBRE A PERDA DA COBERTURA VEGETAL DO BAIRRO PARQUE VERDE - BELÉM\\/PA  

Microsoft Academic Search

O crescimento acelerado das cidades acarretou sérios prejuízos à qualidade ambiental das áreas de expansão urbana, pois a ocupação urbana desordenada configurada nestes espaços substituiu de forma degradante o espaço natural transformando-o em espaço construído sem qualquer planejamento urbano que levasse em conta a vegetação como componente essencial da qualidade de vida humana. Dentro deste contexto, o bairro Parque Verde,

CIÊNCIA EDUCAÇÃO; SUELLEN CRISTINA; VIDAL COSTA; NÍVIA BERNA DA SILVEIRA CORRÊA

191

Natural Gas Monthly, June 1988.  

National Technical Information Service (NTIS)

This monthly report on the natural gas industry covers: dry gas production (wet marketed production minus extraction loss); consumption of natural gas; the average wellhead price of natural gas; the average city-gate price for natural gas delivered to dis...

1988-01-01

192

What Drives Natural Gas Prices?  

Microsoft Academic Search

For many years, fuel switching between natural gas and residual fuel oil kept natural gas prices closely aligned with those for crude oil. More recently, however, the number of U.S. facilities able to switch between natural gas and residual fuel oil has declined, and over the past seven years, U.S. natural gas prices have been on an upward trend with

Stephen P. A. Brown; Mine K. Yucel

2008-01-01

193

Illinois Natural History Survey  

NSDL National Science Digital Library

The University of Illinois at Urbana-Champaign is responsible for the Illinois Natural History Survey (INHS), whose mission is "to investigate and document the biological resources of Illinois...and to acquire and provide natural history information...to promote the common understanding, conservation, and management of these resources." Along the top of the page visitors can find headings that include "Research", "Data", "Publications", and "Events". The "Research" portion of the website includes seven areas of research from which to choose including "Entomology", "Invasive Species", "Wildlife Ecology", and "Human Interactions". The "Data" section provides ecological monitoring data, GIS data, a clearinghouse of wildlife ecology software, and collection databases which allow visitors to search for specimens of plants and animals. The "Publications" include educational materials, annual reports, manuals, a bulletin, and a circular. For those interested in events at the INHS, the "Events" link provides a nice calendar of upcoming seminars.

2009-10-19

194

Safer Liquid Natural Gas  

NASA Technical Reports Server (NTRS)

After the disaster of Staten Island in 1973 where 40 people were killed repairing a liquid natural gas storage tank, the New York Fire Commissioner requested NASA's help in drawing up a comprehensive plan to cover the design, construction, and operation of liquid natural gas facilities. Two programs are underway. The first transfers comprehensive risk management techniques and procedures which take the form of an instruction document that includes determining liquid-gas risks through engineering analysis and tests, controlling these risks by setting up redundant fail safe techniques, and establishing criteria calling for decisions that eliminate or accept certain risks. The second program prepares a liquid gas safety manual (the first of its kind).

1976-01-01

195

Natural environment analysis  

NASA Technical Reports Server (NTRS)

Qualitative analyses (and quantitatively to the extend possible) of the influence of terrain features on wind loading of the space shuttle while on the launch pad, or during early liftoff, are presented. Initially, the climatology and meteorology producing macroscale wind patterns and characteristics fot he Vandenburg Air Force Base (VAFB) launch site are described. Also, limited field test data are analyzed, and then the nature and characteristic of flow disturbances due to the various terrain features, both natural and man-made, are then reviewed. Following this, the magnitude of these wind loads are estimated. Finally, effects of turbulence are discussed. The study concludes that the influence of complex terrain can create significant wind loading on the vehicle. Because of the limited information, it is not possible to quantify the magnitude of these loads.

1985-01-01

196

Investigating Natural Selection  

NSDL National Science Digital Library

In this activity, students experience one mechanism for evolution through a simulation that models the principles of natural selection and helps answer the question 'how might biological change have occurred and been reinforced over time?' Students will discover that species evolve over time and evolution is the consequence of the interaction of the potential for a species to increase in number, the genetic variability of offspring due to mutation and recombination of genes, a finite supply of the resources required for life, and the ensuing selection of those offspring better able to survive and leave offspring in a particular environment. Natural selection and its evolutionary consequences provide a scientific explanation for the fossil record of ancient life forms, as well as for the striking molecular similarities observed among the diverse species of living organisms. The site also contains a list of materials and all information and instructions required to complete this activity.

197

Nature and Nanotechnology  

SciTech Connect

Scientists and engineers are rapidly developing techniques to produce nanostructures for various applications. Applications for nanodevices include electronic components, catalysts, and mechanical systems such as levers and motors. Nature has been developing processes and products at the nano scale throughout the evolutionary process. There are several biochemical processes that involve energy-producing reactors, synthesis, and various mechanical processes. The relationships between the recent accomplishments of scientists and engineers in nanotechnology and evolutionary changes in nature are the subject of this paper. Numerous examples are provided in which the structure of a biological system at the nano-scale relates to some elaborate biological function. The structure and function for biological systems and biochemicals can in some cases be correlated to the structure and function of man-made nanomaterials. In this paper, we focus on proteins, but similar insight can be attained from other biomolecules and a wide variety of biological processes.

Goheen, Steven C.; Gaither, Kari A.; Rayburn, Alfred R.; Thomas Tsakalakos, Ilya A. Ovidko, and Asuri K. Vasudevan

2003-10-01

198

Clathrate hydrates in nature.  

PubMed

Scientific knowledge of natural clathrate hydrates has grown enormously over the past decade, with spectacular new findings of large exposures of complex hydrates on the sea floor, the development of new tools for examining the solid phase in situ, significant progress in modeling natural hydrate systems, and the discovery of exotic hydrates associated with sea floor venting of liquid CO2. Major unresolved questions remain about the role of hydrates in response to climate change today, and correlations between the hydrate reservoir of Earth and the stable isotopic evidence of massive hydrate dissociation in the geologic past. The examination of hydrates as a possible energy resource is proceeding apace for the subpermafrost accumulations in the Arctic, but serious questions remain about the viability of marine hydrates as an economic resource. New and energetic explorations by nations such as India and China are quickly uncovering large hydrate findings on their continental shelves. PMID:21141039

Hester, Keith C; Brewer, Peter G

2009-01-01

199

Notebaert Nature Museum  

NSDL National Science Digital Library

The Notebaert Nature Museum fosters environmental learning through its exhibits and over 100 science and nature programs. The museum puts a particular emphasis on environmental sustainability, with its extensive outdoor Greening Project exhibit and full sized Extreme Green House in the middle of the museum. It also boasts the only year round live butterfly exhibit in the region and River Works, an interactive water exhibit. The Museumâs new Teacher Advisory Board involves educators in brainstorming, evaluating, and piloting educational programming developed by Museum staff, and the Museum's Science Teaching Network is a summer institute and meetings designed to create a collaborative learning environment where teachers work together to develop integrated science curricula using classroom and Museum-based lessons. The website provides information on teacher workshops, field trips off site education, Scouts programs, summer camps, teen programs and community partnerships.

200

Nevada Natural Heritage Program  

NSDL National Science Digital Library

The mission of the Nevada Natural Heritage Program is "to help coordinate the resource needs of Nevada's diverse biological heritage with human activities." Their website presents a wide range of resources for persons who might be interested in learning about their work in such fields as ecology, land management, land use planning, and conservation. A good way to start is in the "Special Program Area" section, which can be found on the left side of the homepage. Here visitors will find "Ecology Program", which provides information about Nevada's diverse biological heritage contained within special reports, vegetation coverage maps, and atlases of Nevada's mountain ranges. That's not all; also available in the special program area are the Rare Plant Atlas, wildflower reports, and information about ongoing efforts to create an online catalog of the mosses, hornworts, and liverworts of Nevada. The site is rounded out by a listing of the laws and regulations which govern the activities of the Nevada Natural Heritage Program.

201

of natural amino acids  

Microsoft Academic Search

A new method for the synthesis of protected N a -(ø-Y-alkyl) amino acids (Y is a thio, amino or carboxy group) and related compounds by reductive alkylation of natural amino acids is reported. These new amino acids serve as building units for the synthesis of backbone-cyclic peptides. They are orthogonally protected at the Æ-amino position by butoxycarbonyl (Boc) or 9-fluorenylmethoxycarbonyl

Gal Bitan; Dan Muller; Ron Kasher; Evgenia V. Gluhov; Chaim Gilon

1997-01-01

202

Texas Nature Trackers  

NSDL National Science Digital Library

Through Texas Nature Trackers projects, you can learn how to gather data about various species found on public lands or on your own property. Collected data is sent to biologists who use the information to gain a better understanding of the status and management needs of various species. The goal of the program is to enable long-term conservation of these species and appreciation among Texas citizens.

Department, Texas P.

203

Nature's Greatest Puzzles  

SciTech Connect

It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit.

Quigg, Chris; /Fermilab

2005-02-01

204

Natural Underwater Adhesives  

PubMed Central

The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent curing.

Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

2011-01-01

205

Peruvian natural dye plants  

Microsoft Academic Search

The use of natural dyes to color textiles and other objects has a long history in Andean South America, but has for the most\\u000a part become a lost technology with the introduction of synthetic dyes. A literature and field survey to recover information\\u000a about the traditional use of dye plants in Peru, from pre-Hispanic to recent times, was accompanied by

Kay K. Antúnez de Mayolo

1989-01-01

206

["Natural" treatments of hypercholesterolemia].  

PubMed

In this article we briefly review the evidence on the effect of different "natural" products on cholesterolemia. Plant stanols and sterols reduce cholesterol intestinal absorption and decrease total and LDL cholesterol by approximately 10%. Polycosanol is a mixture of saturated alcohols that seem to inhibit cholesterol hepatic synthesis and decrease total and LDL cholesterol by up to 25%. The effects on the cholestorolemia of soy and soluble fiber are modest. PMID:17129518

Calvo Romero, J M; Lima Rodríguez, E M

2006-11-01

207

Technology Versus Nature  

NSDL National Science Digital Library

This article, written by a member of the Partnership for Advanced Technology in Housing, discusses building materials and practices that can improve residential installation's resistance to major storms and natural disasters. An example of an area that is using these weather resistant designs is in Florida; the article cites the vulnerability of coastal homes to hurricanes and outlines some efforts to build them in a more structurally sound manner.

Mcnulty, Maureen

2008-01-07

208

Natural Attenuation Tool Kit  

NSDL National Science Digital Library

Created by Julie Crosby, this site provides information and links to agencies and companies concerned with environmental remediation, in particular by natural attenuation. Although some sections are still under construction, Products provides interested parties with links to software and field applications. The Papers section contains four technical papers and six regulatory papers plus two publication metasites maintained by the Environmental Protection Agency (EPA). Other areas of interest at the site include links to government agencies and a list of conferences, updated regularly.

209

Introduction to Natural Selection  

NSDL National Science Digital Library

This lesson is an introduction to natural selection and is suited to any student who is just beginning his or her discovery of evolution. The motivation introduces a species of bird that became (over millions of years) numerous species, through adaptation. The development is a hands-on activity that demonstrates how populations change little by little, generation by generation, due to survival of species that have traits that are beneficial in an environment.

Science Netlinks;

2002-03-28

210

The Nature of Things  

NSDL National Science Digital Library

This site features interactive tools related to The Nature of Things television show. The tools include different videos and descriptions of a wide variety of subjects. Some examples include biomimicry, human illness, indoor pollution, and other issues affecting humans. The subject area covered is a very wide range, but users studying or interested in the human brain, biology of human beings, or relationships between animals will no doubt find this site intriguing.

2007-04-12

211

PBS NATURE: Flight School  

NSDL National Science Digital Library

Flight School is a PBS NATURE companion website for a video production about the amazing recovery of the Whooping Crane. The site includes an interview with Operation Migration's Joseph Duff, information about bird flyways, imprinting, and more. The website links to a downloadable Teacher's Guide, a list of relevant links and books, and desktop images. A short video clip of the whooping cranes in flight is provided as well.

212

Nature by Numbers  

NSDL National Science Digital Library

This 4-minute computer animation highlights three forms in nature that have connections with numbers and geometry. The Fibonacci sequence and the golden ratio are shown relating to the chambered nautilus shell and the sunflower seed pattern. The Delaunay triangulation and Voronoi tessellation are shown to simulate the capillary distribution on a dragonfly wing. Included are descriptions of the mathematics and stills from the production.

2013-02-01

213

Natural History of Hawaii  

NSDL National Science Digital Library

The first Web site (1) is a ThinkQuest entry designed by students from Kapolei Elementary School. Although it's geared toward kids, it offers a great overview of the natural history of Hawaii that should benefit anyone not already familiar with the islands. The next Web site (2), from the Hawaiian Ecosystems at Risk Project, outlines the alien species situation in Hawaii and presents a 10-point action plan for combating this problem. The National Wildlife Health Center of the US Geological Survey describes the projects of the Hawaii Field Station in this straightforward Web site (3). Visitors can take a virtual tour of Oahu's Lyon Arboretum and learn about some of Hawaii's unique flora along the way (4). The Hawaii Natural Area Reserves System Web site (5) contains general descriptions and photos of nature reserves on Kauai, Oahu, Molokai, Maui, and the Big Island. Visitors to the next site (6) can browse a gallery of colorful Hawaiian-themed prints created by naturalist painter N. Robert Wagstaff. Terra Galleria Photography offers another collection of beautiful images, this time of Haleakala National Park. Images from this Web site (7) include photos of the highly endangered silversword plant. The final Web site is an article from ScienceDaily Magazine about some of the efforts to save this rare plant, which serves as a symbol of Hawaii's ecological plight (8).

Sohmer, Rachel.

2002-01-01

214

Future natural gas supplies  

NASA Astrophysics Data System (ADS)

Despite recent optimism about the outlook for the future supply of domestic conventional natural gas, the Congressional Office of Technology Assessment (OTA) finds insufficient evidence to clearly justify either an optimistic or a pessimistic view. In a technical memorandum entitled “U.S. Natural Gas Availability: Conventional Gas Supply Through the Year 2000,” released recently by Rep. Philip R. Sharp (D-Ind,), chairman of the Subcommittee on Fossil and Synthetic Fuels of the Committee on Energy and Commerce, OTA concluded that substantial technical uncertainties prevented a reliable estimation of the likely natural gas production rates for later in this century. Even ignoring the potential for significant changes in gas prices and technology, OTA estimated that conventional gas production by the lower 48 states in the year 2000 could range from 9 to 19 trillion cubic feet (TCF) (0.25 to 0.53 trillion cubic meters), compared to 1982 production of 17.5 TCF. Similarly, production in the year 1990 could range from 13 to 20 TCF.

215

Microflyers: inspiration from nature  

NASA Astrophysics Data System (ADS)

Over the past decade, there has been considerable interest in miniaturizing aircraft to create a class of extremely small, robotic vehicles with a gross mass on the order of tens of grams and a dimension on the order of tens of centimeters. These are collectively refered to as micro aerial vehicles (MAVs) or microflyers. Because the size of microflyers is on the same order as that of small birds and large insects, engineers are turning to nature for inspiration. Bioinspired concepts make use of structural or aerodynamic mechanisms that are observed in insects and birds, such as elastic energy storage and unsteady aerodynamics. Biomimetic concepts attempt to replicate the form and function of natural flyers, such as flapping-wing propulsion and external appearance. This paper reviews recent developments in the area of man-made microflyers. The design space for microflyers will be described, along with fundamental physical limits to miniaturization. Key aerodynamic phenomena at the scale of microflyers will be highlighted. Because the focus is on bioinspiration and biomimetics, scaled-down versions of conventional aircraft, such as fixed wing micro air vehicles and microhelicopters will not be addressed. A few representative bioinspired and biomimetic microflyer concepts developed by researchers will be described in detail. Finally, some of the sensing mechanisms used by natural flyers that are being implemented in man-made microflyers will be discussed.

Sirohi, Jayant

2013-04-01

216

EPA LABORATORIES IMPLEMENT EMS PROGRAM  

EPA Science Inventory

This paper highlights the breadth and magnitude of carrying out an effective Environmental Management System (EMS) program at the U.S. EPA's research and development laboratories. Federal research laboratories have unique operating challenges compared to more centralized industr...

217

3D Inversion of Natural Source Electromagnetics  

NASA Astrophysics Data System (ADS)

The superior depth of investigation of natural source electromagnetic techniques makes these methods excellent candidates for crustal studies as well as for mining and hydrocarbon exploration. The traditional natural source method, the magnetotelluric (MT) technique, has practical limitations because the surveys are costly and time consuming due to the labor intensive nature of ground based surveys. In an effort to continue to use the penetration advantage of natural sources, it has long been recognized that tipper data, the ratio of the local vertical magnetic field to the horizontal magnetic field, provide information about 3D electrical conductivity structure. It was this understanding that prompted the development of AFMAG (Audio Frequency Magnetics) and recently the new airborne Z-Axis Tipper Electromagnetic Technique (ZTEM). In ZTEM, the vertical component of the magnetic field is recorded above the entire survey area, while the horizontal fields are recorded at a ground-based reference station. MT processing techniques yield frequency domain transfer functions typically between 30-720 Hz that relate the vertical fields over the survey area to the horizontal fields at the reference station. The result is a cost effective procedure for collecting natural source EM data and for finding large scale targets at moderate depths. It is well known however that 1D layered structures produce zero vertical magnetic fields and thus ZTEM data cannot recover such background conductivities. This is in sharp contrast to the MT technique where electric fields are measured and a 1D background conductivity can be recovered from the off diagonal elements of the impedance tensor. While 1D models produce no vertical fields, two and three dimensional structures will produce anomalous currents and a ZTEM response. For such models the background conductivity structure does affect the data. In general however, the ZTEM data have weak sensitivity to the background conductivity and while we show that it is possible to obtain the background structure by inverting the ZTEM data alone, it is desirable to obtain robust background conductivity information from other sources. This information could come from a priori geologic and petrophysical information or from additional geophysical data such as MT. To counter the costly nature of large MT surveys and the limited sensitivity of the ZTEM technique to the background conductivity we show that an effective method is to collect and invert both MT and ZTEM data. A sparse MT survey grid can gather information about the background conductivity and deep structures while keeping the survey costs affordable. Higher spatial resolution at moderate depths can be obtained by flying multiple lines of ZTEM data.

Holtham, E. M.; Oldenburg, D. W.

2010-12-01

218

Antibody responses in the wild vole, Clethrionomys rufocanus bedfordiae, naturally infected with Echinococcus multilocularis by western blotting.  

PubMed

Antibody responses against crude antigens and the two (Em18 and Em16) epitopes of Echinococcus multilocularis were analysed by Western blotting using sera from the wild vole, Clethrionomys rufocanus bedfordiae (Crb), which were captured in Hokkaido, Japan and found to have been naturally infected with eggs, and compared with those in patients of AHD and mice experimentally infected with protoscoleces of this parasite. Antibody responses in the wild were demonstrated most clearly with anti-Crb-IgG antiserum but more faintly with anti-rat-IgG antiserum and poorly with anti-mouse-IgG or anti-human-IgG antisera or Protein G. Although only two serum samples of the wild vole found naturally infected were analysed, antibody responses against Em18 and Em16 in these voles appeared to be similar to those in AHD patients but differed from those in mice. PMID:7530265

Ito, A; Nakao, M; Ito, M; Matsuzaki, T; Kamiya, M; Kutsumi, H

1994-09-01

219

Nature of Light  

NSDL National Science Digital Library

Overview: The Nature of Light SciPack explains the concept of light as electromagnetic radiation and as waves. It covers the electromagnetic spectrum and the effects of wavelength on the interaction of light with different materials, including some examples of phenomena that can be explained by differences in wavelength. It also covers electromagnetic waves as a form of energy. It does not address the ray model of light or optics. In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components: Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. Access to one-on-one support via e-mail to content "Wizards". Final Assessment which can be used to certify mastery of the concepts. Learning Outcomes: Nature of Light: Characteristics of Light Trace a light ray as it hits a smooth reflecting surface, or, choose the correct path among given options. Predict the path of a light ray as it passes through a series of transparent materials (given the index of refraction of each material). Describe the behavior of light waves as they are diffract (or bend) around corners. Recognize examples of phenomena in your environment that are caused by the diffraction or interference of waves (the fact that you can hear someone around a corner, the behavior of water waves, light through diffraction grating). Nature of Light: Light As Waves Provide examples of energy transfer by light (such as tanning, light warming a surface, solar cells, etc.) Describe the characteristics of transverse waves and explain how waves transfer energy from place to place. Describe the relationship between the wavelength and frequency of light waves. Explain how electromagnetic waves are produced either in nature or by humans. Identify the various parts of the electromagnetic spectrum, and place them in order of increasing or decreasing wavelength. Determine the behavior of two light waves that interfere with one another. Nature of Light: Light and Color Describe the relationship of color as perceived by the human eye and the wavelength of light waves. Describe the relationship of the colors in the visible spectrum (as perceived by the human eye) to the electromagnetic spectrum. Describe how the color of a beam of light is affected by scattering. Summarize the interaction of the molecules of greenhouse gases and different wavelengths of light, and how that results in heat being trapped in the troposphere. Nature of Light: So, What Is Light? Describe the circumstances (experiments, real world situations) in which the behavior of light is best described as a wave or a particle. Describe the relationship between the frequency of a photon and its energy. Explain how a unique series of spectral lines are formed for an element (an atom or a group of free atoms of that element). Describe how spectra can be used to identify substances.

National Science Teachers Association (NSTA)

2009-05-01

220

Myxobacteria: natural pharmaceutical factories  

PubMed Central

Myxobacteria are amongst the top producers of natural products. The diversity and unique structural properties of their secondary metabolites is what make these social microbes highly attractive for drug discovery. Screening of products derived from these bacteria has revealed a puzzling amount of hits against infectious and non-infectious human diseases. Preying mainly on other bacteria and fungi, why would these ancient hunters manufacture compounds beneficial for us? The answer may be the targeting of shared processes and structural features conserved throughout evolution.

2012-01-01

221

Nature: Extraordinary Birds  

NSDL National Science Digital Library

This Web site is the online companion to Extraordinary Birds, a recent documentary from PBS's Nature. "From Kundha Kulam's vibrant monsoon marshes to the rugged American Rockies," Extraordinary Birds explores the "intimate links that people have forged with birds." This is a great site to visit whether you've seen the program or not. Users will find video clips, an interview with the editor of American Falconry magazine, a short quiz, and other engaging features. The Web site also provides links and other resources for further exploring this fascinating subject. This site is also reviewed in the September 5, 2003 NSDL Life Sciences Report.

222

Natural treatments for osteoarthritis.  

PubMed

Osteoarthritis (OA) is the most common form of joint disease. Although OA was previously thought to be a progressive, degenerative disorder, it is now known that spontaneous arrest or reversal of the disease can occur. Conventional medications are often effective for symptom relief, but they can also cause significant side effects and do not slow the progression of the disease. Several natural substances have been shown to be at least as effective as nonsteroidal anti-inflammatory drugs at relieving the symptoms of OA, and preliminary evidence suggests some of these compounds may exert a favorable influence on the course of the disease. PMID:10559548

Gaby, A R

1999-10-01

223

The Natural Science Pages  

NSDL National Science Digital Library

Anthony Carpi, assistant professor at John Jay College of Criminal Justice, provides the Natural Science Pages. The site is divided into two primary sections, NSC 107 course-specific material (online supplement to students enrolled in this course at John Jay College) and course lessons (general use). The topics covered in the Course Lessons are Scientific Method, Matter & Energy, Atomic Structure, Periodic Table, Atomic Bonding, Reactions, Acids & Bases, Nuclear Science, The Universe, Organic Chem, Nutrients, DNA, The Cell, and Basic Anatomy. Descriptions, images, diagrams, and links to related resources are provided for each topic. This is an excellent learning resource and is well worth a visit.

224

Natural Selection Simulation  

NSDL National Science Digital Library

This classroom activity introduces the concept of natural selection and how it relates to evolution. Students will use a variety of utensils including clothespins, tweezers and spoons to mimic animals with differently shaped mouths. The class will go through several trials, picking up at least twenty beans in one minute with their assigned utensil. If they fail to do so, their creature has died, demonstrating what happens to animals that cannot compete in the wild. Several discussion questions are included along with the activity.

2012-05-29

225

"Naturally occurring asbestos  

NASA Astrophysics Data System (ADS)

The term asbestos refers to six silicate minerals from amphibole and serpentine groups. By definition, it consists in bundles of thin and flexible long fibers, with high-tensile strength, and chemical and heat resistance. In contrast to asbestos found within commercial products and mining, the specific term ''naturally occurring asbestos'' (NOA) refers to asbestiform minerals occurring within rocks or soils that can be released by human activities or weathering processes. The fact that the exposure to asbestos is related to lung pathologies is now widely demonstrated (e.g. asbestosis, mesothelioma and lung cancer). However, if health risks associated with exposure to NOA exist, they are not yet well documented. The crystallization of natural asbestos occurs in specific Mg-rich lithologies associated with peculiar structural and metamorphic conditions. By recognizing and combining such specific geologic criteria, the presence or the absence of asbestos in bedrock terrains can be reasonably predicted and maps of NOA hazard can be drawn. We present here new results of geological mapping and petrological study concerning the evaluation of the NOA hazard in the Alps and Corsica, in France. The three folds approach consists in (1) a determination of lithologies with potential NOA from a bibliographic compilation and extraction of target zones from a geological geodatabase (2) a geological mapping of the target zones followed by a petrological characterization of sampled asbestiform minerals in the laboratory (optical microscopy, TEM, SEM, and Raman spectroscopy technics), and (3) the drawing of the final map of NOA hazard, at regional-scale. Occurrence criteria can be retained as follows: 1. NOA are abundant in the internal zones of the Alps and Corsica, especially within ophiolitic complexes. Natural asbestos are mostly concentrated within ultramafic rocks but can also occur within basic lithologies such as Mg-metagabbros, metabasalts and meta-pillow-lavas, 2. Asbestos is commonly located within fractures, shear-bands or shear-planes, developed during late retrograde metamorphic history, 3. Tremolite-actinolite-type asbestos is abundant both in ultramafic and mafic rocks, 4. Natural asbestos occur in few places within the external zones of the Alps, especially within hercynian ophiolitic massifs or concentrated in late Alpine fractures affecting leptyno-amphibolic lithologies.

Cagnard, F.; Lahondère, D.; Blein, O.; Lahfid, A.; Wille, G.

2012-04-01

226

Patterns in Nature  

NSDL National Science Digital Library

This page is a companion to the Exploring Patterns in Nature Curriculum Guides (see related pages) developed by the Center for Polymer Studies. It represents several basic Java Applets which illustrate basic concepts in statistical mechanics and fractals. Note that these programs do not necessarily match the software instructions in our curriculum guides. The guides were written to correspond to standalone software developed in the early 1990s. Since Apple Macintosh computers were most popular in schools at the time, we developed for that platform. Those programs were all Mac System 7 compatible and obviously are not OS X compatible. We have plans to breathe new life into these programs and curriculum.

Mcgath, Gary; Trunfio, Paul

2008-12-31

227

The Nature of Salt  

NSDL National Science Digital Library

This is a hands-on lab activity about the composition of salt. Learners will explain the general relationship between an element's Periodic Table Group Number and its tendency to gain or lose electron(s), and explain the difference between molecular compounds and ionic compounds. They will then use household materials to build a model to demonstrate sodium chloride's cubic form and describe the nature of the electrostatic attraction that holds the structure of salt together. Background information, common preconceptions, a glossary and more is included. This activity is part of the Aquarius Hands-on Laboratory Activities.

228

Nature.com Blogs  

NSDL National Science Digital Library

This site brings together all of the blogs for the Nature Publishing Group, including discussions on public health, genetics, chemistry, and other interesting topics. First-time visitors can glance over recent meditations from British physicians on new and improved surgical operations and the Higgs-Boson particle. Visitors can read through one or all of the fifteen blogs or scroll down to the New Comments and Popular areas. In this last section, visitors can get a sense of the Most Read, Most Shared, and Most Commented items by other readers.

229

Characterization of natural fiber surfaces and natural fiber composites  

Microsoft Academic Search

Experiments have been performed to further the development of natural fiber reinforced composites as a replacement for glass fiber composites. Untreated and treated surfaces of natural fibers were characterized using FTIR, XPS, and ESEM. Changes in the peaks in the FTIR spectrum at 1730, 1625 and 1239cm?1 indicated that the alkali treatment removes hemicellulose and lignin from natural fiber surfaces.

N. Sgriccia; M. C. Hawley; M. Misra

2008-01-01

230

Naturally prion resistant mammals  

PubMed Central

Each known abnormal prion protein (PrPSc) is considered to have a specific range and therefore the ability to infect some species and not others. Consequently, some species have been assumed to be prion disease resistant as no successful natural or experimental challenge infections have been reported. This assumption suggested that, independent of the virulence of the PrPSc strain, normal prion protein (PrPC) from these ‘resistant’ species could not be induced to misfold. Numerous in vitro and in vivo studies trying to corroborate the unique properties of PrPSc have been undertaken. The results presented in the article “Rabbits are not resistant to prion infection” demonstrated that normal rabbit PrPC, which was considered to be resistant to prion disease, can be misfolded to PrPSc and subsequently used to infect and transmit a standard prion disease to leporids. Using the concept of species resistance to prion disease, we will discuss the mistake of attributing species specific prion disease resistance based purely on the absence of natural cases and incomplete in vivo challenges. The BSE epidemic was partially due to an underestimation of species barriers. To repeat this error would be unacceptable, especially if present knowledge and techniques can show a theoretical risk. Now that the myth of prion disease resistance has been refuted it is time to re-evaluate, using the new powerful tools available in modern prion laboratories, whether any other species could be at risk.

Fernandez-Borges, Natalia; Chianini, Francesca; Erana, Hasier; Vidal, Enric; Eaton, Samantha L; Pintado, Belen; Finlayson, Jeanie; Dagleish, Mark P.; Castilla, Joaquin

2012-01-01

231

Thermoacoustic natural gas liquefier  

SciTech Connect

In collaboration with Cryenco Inc. and NIST-Boulder, we intend to develop a natural gas-powered natural-gas liquefier which has absolutely no moving parts and requires no electrical power. It will have high efficiency, remarkable reliability, and low cost. Progress on the liquefier to be constructed at Cryenco continues satisfactorily. The thermoacoustic driver is still ahead of the pulse tube refrigerator, because of NIST`s schedule. We completed the thermoacoustics design in the fall of 1994, with Los Alamos providing physics input and checks of all aspects, and Cryenco providing engineering to ASME code, drafting, etc. Completion of this design represents a significant amount of work, especially in view of the many unexpected problems encountered. Meanwhile, Cryenco and NIST have almost completed the design of the pulse tube refrigerator. At Los Alamos, we have assembled a half-size scale model of the thermoacoustic portion of the 500 gal/day TANGL. This scale model will enable easy experimentation in harmonic suppression techniques, new stack geometries, new heat-exchanger geometries, resonator coiling, and other areas. As of March 1995, the scale model is complete and we are performing routine debugging tests and modifications.

Swift, G.W. [Los Alamos National Lab., NM (United States)

1995-06-01

232

Merging toward natural clusters  

NASA Astrophysics Data System (ADS)

To findout how many clusters exist in a sample set is an old yet unsolved problem in unsupervised clustering. This problem inevitably occurs in region merging/growing, a well studied and popular technique in image segmentation. Region merging usually needs a stop criterion. The stop criterion is not automatically determined and often has to be set manually to arrive at a sensible segmentation, which is rather difficult for natural images. To address this problem, we present a robust stop criterion that is based on a novel distinctness predicate for adjacent regions. The predicate discerns distinct regions by examining the evidence of the boundary between neighboring regions. Requiring that every region should be distinct from each other, the proposed method is able to choose a stop point where a natural partition is most likely. Under a region merging framework, we demonstrate the effectiveness of the stop criterion using two merging criterion: one based on optimizing a global functional, and another based on a local criterion. Experimental results and comparison are given at the end.

Tan, Zhi-Gang; Yung, Nelson H. C.

2009-07-01

233

En-gauging naturalness  

NASA Astrophysics Data System (ADS)

The discovery of a 125.5 GeV Higgs with standard model-like couplings and naturalness considerations motivate gauge extensions of the MSSM. We analyse two variants of such an extension and carry out a phenomenological study of regions of the parameter space satisfying current direct and indirect constraints, employing state-of-the-art two-loop RGE evolution and GMSB boundary conditions. We find that due to the appearance of non-decoupled D-terms it is possible to obtain a 125.5 GeV Higgs with stops below 2 TeV, while the uncoloured sparticles could still lie within reach of the LHC. We compare the contributions of the stop sector and the non-decoupled D-terms to the Higgs mass, and study their effect on the Higgs couplings. We further investigate the nature of the next-to lightest supersymmetric particle, in light of the GMSB motivated searches currently being pursued by ATLAS and CMS.

Bharucha, Aoife; Goudelis, Andreas; McGarrie, Moritz

2014-05-01

234

X-Ray, Optical, and Radio Observations of the Type II Supernovae 1999em and 1998S  

Microsoft Academic Search

Observations of the Type II-P (plateau) supernova SN 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio

David Pooley; Walter H. G. Lewin; Derek W. Fox; Jon M. Miller; Christina K. Lacey; Schuyler D. Van Dyk; Kurt W. Weiler; Richard A. Sramek; Alexei V. Filippenko; Douglas C. Leonard; Stefan Immler; Roger A. Chevalier; Andrew C. Fabian; Claes Fransson; Ken'ichi Nomoto

2002-01-01

235

Natural Emissions of Oxidant Precursors.  

National Technical Information Service (NTIS)

The paper provides an overview of the sources, the estimation methodology, and the relative amounts of natural hydrocarbon and nitrogen oxide emissions. The most recent estimate of natural nonmethane hydrocarbon (NMHC) emissions for the United States is 2...

J. H. Novak T. E. Pierce

1991-01-01

236

Natural gas monthly, December 1995  

SciTech Connect

This report presents information of interest to organizations associated with the natural gas industry. Data are presented on natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also included.

NONE

1995-12-01

237

Natural gas monthly, June 1997  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 24 tabs.

NONE

1997-06-01

238

Natural gas monthly, July 1994  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

Not Available

1994-07-20

239

Natural gas monthly, November 1995  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

NONE

1995-12-05

240

Natural fracturing, by depth  

NASA Astrophysics Data System (ADS)

Natural opening-mode fractures commonly fall upon a spectrum whose end-members are veins, which have wide ranges of sizes and are mostly or thoroughly cemented, and joints, which have little opening displacement and little or no cement. The vein end-member is common in metamorphic rocks, whose high temperature and pressure of formation place them outside typical reservoir settings; conversely, many uncemented joints likely form near the surface and so too have limited relevance to subsurface exploration. Sampling of cores retrieved from tight-gas sandstone reservoirs suggest that it is intermediate fractures, not true joints or veins, that provide natural porosity and permeability. Such fractures have abundant pore space among fracture-bridging cements, which may hold fractures open despite varying states of stress through time. Thus the more sophisticated our understanding of the processes that form veins and joints, i.e., how natural fracturing varies by depth, the better our ability to predict intermediate fractures. Systematic differences between veins and joints, in terms of size-scaling and lateral and stratigraphic spatial arrangement, have been explained in the literature by the mechanical effects of sedimentary layering, which likely exert more control over fracture patterns at shallower depths. Thus stratabound joints commonly have narrow size ranges and regular spacing; non-stratabound veins have a wide range of sizes and spacings. However, new fieldwork and careful literature review suggest that the effects of mechanical layering are only half the story. Although atypical, veins may be highly stratabound and yet spatially clustered; non-stratabound fractures may nonetheless feature narrow size ranges. These anomalous fracture arrangements are better explained by the presence of precipitating cements during fracture opening than by mechanical layering. Cement is thought to be highly important for fracture permeability, but potential effects of synkinematic cement on fracture size and spacing have been largely overlooked. Such effects are currently poorly understood, but numerical models of fracture widening amid precipitating cements can replicate observed size-scaling patterns. Synkinematic fracture-bridging cements can also potentially account for irregular fracture spacing in stratabound fracture arrays.

Hooker, John; Laubach, Stephen

2013-04-01

241

Natural Language Comes of Age.  

ERIC Educational Resources Information Center

Discusses natural language retrieval systems, focusing on West Publishing Company's WIN (Westlaw Is Natural) system used with its case law database. Information retrieval models, the advantages and disadvantages of natural language retrieval, and the use of the approach by Congressional Quarterly's Washington Alert, Personal Librarian, and other…

Pritchard-Schoch, Patricia

1993-01-01

242

Nature and Nationhood: Danish Perspectives  

ERIC Educational Resources Information Center

In this paper, I shall discuss Danish perspectives on nature, showing the interdependence of conceptions of "nature" and "nationhood" in the formations of a particular cultural community. Nature, thus construed, is never innocent of culture and cannot therefore simply be "restored" to some pristine, pre-lapsarian state. On the other hand,…

Schnack, Karsten

2009-01-01

243

Economics of natural gas upgrading  

Microsoft Academic Search

Natural gas could be an important alternative energy source in meeting some of the market demand presently met by liquid products from crude oil. This study was initiated to analyze three energy markets to determine if greater use could be made of natural gas or natural gas derived products and if those products could be provided on an economically competitive

J. H. Hackworth; R. W. Koch

1995-01-01

244

Children's Moral Relationships with Nature.  

ERIC Educational Resources Information Center

Two studies of the development of children's moral relationships with nature addressed such questions as: (1) What does it mean to say that we have an obligation not to harm the natural environment? (2) Does the natural environment feel pain? (3) Does it have rights? or (4) Is moral obligation an inappropriate construct by which to understand the…

Kahn, Peter H., Jr.; McCoy, Ann

245

Natural gas pipeline technology overview  

Microsoft Academic Search

The United States relies on natural gas for one-quarter of its energy needs. In 2001 alone, the nation consumed 21.5 trillion cubic feet of natural gas. A large portion of natural gas pipeline capacity within the United States is directed from major production areas in Texas and Louisiana, Wyoming, and other states to markets in the western, eastern, and midwestern

S. M. Folga

2007-01-01

246

US crude oil, natural gas, and natural gas liquids reserves  

SciTech Connect

This report presents estimates of proved reserves of crude oil, natural gas, and natural gas liquids as of December 31, 1989, and production volumes for the year 1989 for the total United States and for selected states and state sub-divisions. Estimates are presented for the following four categories of natural gas: total gas (wet after lease separation), its two major components (nonassociated and associated-dissolved gas), and total dry gas (wet gas adjusted for the removal of liquids at natural gas processing plants). In addition, two components of natural gas liquids, lease condensate and natural gas plant liquids, have their reserves and production reported separately. Also included is information on indicated additional crude oil reserves and crude oil, natural gas, and lease condensate reserves in nonproducing reservoirs. 28 refs., 9 figs., 15 tabs.

Not Available

1990-10-05

247

The nature of confidentiality.  

PubMed Central

This paper examines confidentiality and its nature and analyses the guidelines laid down by the Hippocratic Oath as well as the British and World Medical Associations for maintaining such confidentiality between doctor and patient. There are exceptions to practically any code of rules and this is true also for confidentiality. Some of these exceptions make it appear that very little is confidential. The three values implicit in confidentiality would seem to be privacy, confidence and secrecy. Each of these values is discussed and developed in this paper. In conclusion, the question is suggested that maybe in the face of death, doctor and patient need to re-examine the pre-suppositions of privacy, confidence and secrecy on which the confidential relationship is based.

Thompson, I E

1979-01-01

248

Necessity and natural categories.  

PubMed

Our knowledge of natural categories includes beliefs not only about what is true of them but also about what would be true if the categories had properties other than (or in addition to) their actual ones. Evidence about these beliefs comes from three lines of research: experiments on category-based induction, on hypothetical transformations of category members, and on definitions of kind terms. The 1st part of this article examines results and theories arising from each of these research streams. The 2nd part considers possible unified theories for this domain, including theories based on ideals and norms. It also contrasts 2 broad frameworks for modal category information: one focusing on beliefs about intrinsic or essential properties, the other focusing on interacting causal relations. PMID:11726073

Rips, L J

2001-11-01

249

Natural Radioactivity in Bananas  

SciTech Connect

The content of {sup 40}K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, Sao Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil without fertilizer for comparison. We have used the gamma-ray spectroscopy technique with a NaI(T1) crystal inside a 12 cm thick lead shield to detect the gamma-radiation. The results indicate that only part of the available potassium is absorbed by the plant, which is mainly concentrated in the banana peel.

Zagatto, V. A. B.; Medina, N. H.; Okuno, E.; Umisedo, N. K. [Instituto de Fisica da Universidade de Sao Paulo (Brazil)

2008-08-07

250

Natural Radioactivity in Bananas  

NASA Astrophysics Data System (ADS)

The content of 40K natural radionuclide in bananas (Musa sapientum) from the Vale do Ribeira region, Sa~o Paulo, Brazil, has been measured. We have collected several samples of bananas prata and nanica, its peels, leaves, and also different soils where the banana tree was planted, such as soil with a standard amount of fertilizer, the fertilizer itself and also soil without fertilizer for comparison. We have used the gamma-ray spectroscopy technique with a NaI(T1) crystal inside a 12 cm thick lead shield to detect the gamma-radiation. The results indicate that only part of the available potassium is absorbed by the plant, which is mainly concentrated in the banana peel.

Zagatto, V. A. B.; Medina, N. H.; Okuno, E.; Umisedo, N. K.

2008-08-01

251

Natural flexible dermal armor.  

PubMed

Fish, reptiles, and mammals can possess flexible dermal armor for protection. Here we seek to find the means by which Nature derives its protection by examining the scales from several fish (Atractosteus spatula, Arapaima gigas, Polypterus senegalus, Morone saxatilis, Cyprinius carpio), and osteoderms from armadillos, alligators, and leatherback turtles. Dermal armor has clearly been developed by convergent evolution in these different species. In general, it has a hierarchical structure with collagen fibers joining more rigid units (scales or osteoderms), thereby increasing flexibility without significantly sacrificing strength, in contrast to rigid monolithic mineral composites. These dermal structures are also multifunctional, with hydrodynamic drag (in fish), coloration for camouflage or intraspecies recognition, temperature and fluid regulation being other important functions. The understanding of such flexible dermal armor is important as it may provide a basis for new synthetic, yet bioinspired, armor materials. PMID:23161399

Yang, Wen; Chen, Irene H; Gludovatz, Bernd; Zimmermann, Elizabeth A; Ritchie, Robert O; Meyers, Marc A

2013-01-01

252

Nature of Light  

NSDL National Science Digital Library

What is light? Our experience with light is that which we can see. Our eyes contain two different types of photoreceptors, rods and cones. Rods are extremely sensitive to light but can't distinguish color. Cones which are less sensitive than rods, respond to light of different wavelengths, producing color vision. Instruction for understanding light begins with an understanding of mechanical waves and the properties of those waves. However, light also has particle-like properties, and exhibits a wave-particle duality. This SciGuide breaks down the complexity of teaching the nature of light into manageable chunks arranged in a logical sequence for learning. You may choose specific Themes or Keywords appropriate to your students and teaching objectives. Individual Themes and Keywords identify misconceptions and conceptual difficulties. Many web resources provide simulations and data to enhance understanding and engage students in inquiry.

National Science Teachers Association (NSTA)

1900-01-01

253

Nature: Katrina's Animal Rescue  

NSDL National Science Digital Library

There have been many stories that have come out in the aftermath of Hurricane Katrina, and most of them have dealt with the human tragedies involved in this traumatic set of events. The people at the long-running PBS series, Nature, have created this website to complement a recent edition of the show that offered some insights into the effects the hurricane had on the animal population of Louisiana. On the site, visitors can take advantage of a number of special interactive features. These features allow visitors to ask questions of those involved in the animal rescue efforts and learn about the psychological and physical effects on animals. The site also contains a section where visitors can learn about other web-based resources, such as the homepages for Animal Rescue New Orleans and the Best Friends Animal Society.

2005-01-01

254

Patterns in Nature  

NSDL National Science Digital Library

This math/science project was centered around patterns in nature and was funded by an Appalachian Educational Laboratory grant. The grant paid for travel among the three schools, materials for research, and the Science/Math showcase. It involved fifty sophomore students who were taking biology and geometry with the same two teachers for the last two periods of the school day. It also involved two fourth grade classes at different elementary schools. High school students researched math/science topics including fractals, Fibonaccis numbers, whale and butterfly migration patterns, whale identification, flower patterns, biorhythms, fingerprints, planetary alignment, fossils, human body proportions, bee and wasp nests and spider webs. Working in cooperative groups with fourth grade students, they designed models of these concepts. The culminating event was a Science/Math showcase where the students displayed and explained their models.

BEGIN:VCARD VERSION:2.1 FN:Peggy Welch N:Welch;Peggy ORG:West Jessamine High School REV:2005-04-12 END:VCARD

1995-06-30

255

Liquefied Natural Gas Transfer  

NASA Technical Reports Server (NTRS)

Chicago Bridge & Iron Company's tanks and associated piping are parts of system for transferring liquefied natural gas from ship to shore and storing it. LNG is a "cryogenic" fluid meaning that it must be contained and transferred at very low temperatures, about 260 degrees below Fahrenheit. Before the LNG can be pumped from the ship to the storage tanks, the two foot diameter transfer pipes must be cooled in order to avoid difficulties associated with sharp differences of temperature between the supercold fluid and relatively warm pipes. Cooldown is accomplished by sending small steady flow of the cryogenic substance through the pipeline; the rate of flow must be precisely controlled or the transfer line will be subjected to undesirable thermal stress.

1980-01-01

256

Natural rubber latex allergy.  

PubMed

Rubber is an important industrial and consumer product encountered in many household items and medical devices. Whereas the chemical additives used in its manufacture are well recognized as a cause of delayed-type hypersensitivity (allergic contact dermatitis), it is only during the past decade that immediate-type allergy to natural rubber latex (NRL) proteins (latex allergy) has emerged as a serious health issue. Frequent, prolonged wearing of NRL gloves, especially amongst health care workers, is a major risk factor for such sensitization. Latex allergy is now an important medical, occupational, medico-legal and financial problem, and it is essential that policies are developed to reduce it. Undiagnosed latex allergy is potentially very serious for patients. This article briefly overviews latex allergy with emphasis on the practical issues of diagnosis and management. PMID:10457121

Wakelin, S H; White, I R

1999-07-01

257

Natural Products for Cancer Prevention  

PubMed Central

OBJECTIVES To review the clinical trial literature on the use and effects of natural products for cancer prevention. DATA SOURCES Clinical trials published in PubMed. CONCLUSION There is a growing body of literature on the use of natural products for cancer prevention. To date, few trials have demonstrated conclusive benefit. Current guidelines recommend against the use of natural products for cancer prevention. IMPLICATIONS FOR NURSING PRACTICE Clinicians should ask patients about their use of natural products and motivations for use. If patients are using natural products specifically for cancer prevention, they should be counseled on the current guidelines, as well as their options for other cancer prevention strategies.

Greenlee, Heather

2013-01-01

258

Natural gas monthly, July 1997  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The feature article this month is entitled ``Intricate puzzle of oil and gas reserves growth.`` A special report is included on revisions to monthly natural gas data. 6 figs., 24 tabs.

NONE

1997-07-01

259

Natural gas monthly, May 1997  

SciTech Connect

The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The feature article this month is ``Restructuring energy industries: Lessons from natural gas.`` 6 figs., 26 tabs.

NONE

1997-05-01

260

Natural gas monthly, May 1994  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The featured articles for this month are: Opportunities with fuel cells, and revisions to monthly natural gas data.

Not Available

1994-05-25

261

Natural gas monthly, June 1996  

SciTech Connect

The natural gas monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The feature article for this month is Natural Gas Industry Restructuring and EIA Data Collection.

NONE

1996-06-24

262

Natural gas monthly, June 1994  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The feature article this month is the executive summary from Natural Gas 1994: Issues and Trends. 6 figs., 31 tabs.

Not Available

1994-06-01

263

Natural Gas Monthly, October 1993  

SciTech Connect

The (NGM) Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. This month`s feature articles are: US Production of Natural Gas from Tight Reservoirs: and Expanding Rule of Underground Storage.

Not Available

1993-11-10

264

Natural radioactivity in water supplies  

SciTech Connect

This book outlines the scientific aspects of the control of natural radioactivity in water supplies, as well as the labyrinthine uncertainties in water quality regulation concerning natural radiocontamination of water. The author provides an introduction to the theory of natural radioactivity; addresses risk assessment, sources of natural radiocontamination of water, radiobiology of natural radioactivity in water, and federal water law concerning natural radiocontamination. It presents an account of how one city dealt with the perplexes that mark the rapidly evolving area of water quality regulation. The contents include: radioactivity and risk; an introduction to the atomic theory; an introduction to natural radioactivity; risk assessment; uranium and radium contamination of water; radiobiology of uranium and radium in water. Determination of risk from exposure to uranium and radium in water; the legal milieu; one city's experience; and summary: the determinants of evolving regulation.

Horner, J.K.

1985-01-01

265

Crude oil and natural gas pricing. Chapters 300 to 499: natural gas liquids, natural gas  

Microsoft Academic Search

This text analyzes the federal statutes and regulations that affect the pricing and allocation of crude oil, natural gas, and natural gas liquids. It does not cover refined products or imported crude oil except where necessary to place major decisions in historical context. Chapter 300 concerns natural gas liquids. For historical rather than logical reasons, these are regulated as an

1980-01-01

266

Spatial EM jamming: A countermeasure against EM Analysis?  

Microsoft Academic Search

Electro-Magnetic Analysis has been identified as an efficient technique to retrieve the secret key of cryptographic algorithms. Although similar mathematically speaking, Power or Electro-Magnetic Analysis have different advantages in practice. Among the advantages of EM Analysis, the feasibility of attacking limited and bounded area of integrated systems is the key one. Within this context, the contribution of this paper is

Francois Poucheret; Lyonel Barthe; Pascal Benoit; Lionel Torres; Philippe Maurine; Michel Robert

2010-01-01

267

WRF nature run  

NASA Astrophysics Data System (ADS)

The Weather Research and Forecast (WRF) model is a model of the atmosphere for mesoscale research and operational numerical weather prediction (NWP). A petascale problem for WRF is a nature run that provides very high-resolution 'truth' against which more coarse simulations or perturbation runs may be com-pared for purposes of studying predictability, stochastic parameterization, and fundamental dynamics. We carried out a nature run involving an idealized high resolution rotating fluid on the hemisphere, at a size and resolution never before attempted, and used it to investigate scales that span the k-3 to k-5/3 kinetic energy spectral transition, via simulations. We used up to 15,360 processors of the New York Blue IBM BG/L machine at Stony Brook Uni-versity and Brookhaven National Laboratory. The grid we employed has 4486 by 4486 horizontal grid points and 101 vertical levels (2 billion cells) at 5km resolution; this is 32 times larger than the previously largest 63 million cell 2.5km resolution WRF CONUS benchmark [10]). To solve a problem of this size, we worked through issues of parallel I/O and scalability and employed more processors than have ever been used in a WRF run. We achieved a sustained 3.4 Tflop/s on the New York Blue sys-tem, inputting and then generating an enormous amount of data to produce a scientifically meaningful result. More than 200 GB of data was input to initialize the run, which then generated output datasets of 40 GB each simulated hour. The cost of output was considered a key component of our investigation. Then we ran the same problem on more than 12K processors of the XT4 system at NERSC and achieved 8.8 Tflop/s. Our primary result however is not just scalability and a high Tflop/s number, but capture of atmosphere features never before represented by simulation, and taking an important step towards understanding weather predict-ability at high resolution.

Michalakes, J.; Hacker, J.; Loft, R.; McCracken, M. O.; Snavely, A.; Wright, N. J.; Spelce, T.; Gorda, B.; Walkup, R.

2008-07-01

268

Naturally occurring triterpenoid saponins.  

PubMed

Naturally occurring new triterpenoid saponins reported from mid-1996 to March, 2007 are reviewed including their physical constants and plant sources, and are compiled in Table 1. New saponins are arranged in Table 1 on the basis of the skeletal structures of their aglycones, e.g., oleanane type, ursane type, lupane type, hopane type, taraxastane type, cycloartane type, lanostane type, tirucallane type, dammarane type, cucurbitane type, and holostane type. The known triterpenoid saponins and prosapogenins of the new saponins, the biological and pharmacological activities of which were published during 1996-2007, are also reviewed together with their plant sources listed in Table 2 according to the skeletal structures of their aglycones in the same fashion as in Table 1. The plant and animal sources of both new and known bioactive triterpenoid saponins are collected in Table 3 in alphabetical order. The biological and pharmacological activities such as antiallergic, antiatherosclerosis and antiplatelet, antibacterial, anticomplementary, antidiabetic, contraceptive, antifungal, anti-inflammatory, antileishmanial, antimalarial/antiplasmodial, anti-obesity, anti-proliferative, antipsoriatic, antispasmodic, antisweet, antiviral, cytotoxic/antitumor, detoxication, gastroprotective, haemolytic, hepatoprotective, immunomodulatory, anti-enzyme, anti-osteoporotic, insecticidal, insulin-like, membrane-porosity, molluscicidal, neuropharmacological, anti-endothelial dysfunction, snake venom antidote, and sweet activities of these saponins or derived prosapogenins are discussed briefly after Table 3. PMID:20963775

Dinda, Biswanath; Debnath, Sudhan; Mohanta, Bikas Chandra; Harigaya, Yoshihiro

2010-10-01

269

SUSY naturalness without prejudice  

NASA Astrophysics Data System (ADS)

Unlike the Standard Model (SM), supersymmetric models stabilize the electroweak (EW) scale v at the quantum level and predict that v is a function of the TeV-valued SUSY parameters (??) of the UV Lagrangian. We show that the (inverse of the) covariance matrix of the model in the basis of these parameters and the usual deviation ??2 (from ?min2 of a model) automatically encode information about the "traditional" EW fine-tuning measuring this stability, provided that the EW scale v ˜mZ is indeed regarded as a function v =v(?). It is known that large EW fine-tuning may signal an incomplete theory of soft terms and can be reduced when relations among ?? exist (due to GUT symmetries, etc.). The global correlation coefficient of this matrix can help one investigate if such relations are present. An upper bound on the usual EW fine-tuning measure ("in quadrature") emerges from the analysis of the ??2 and the s-standard deviation confidence interval by using v =v(?) and the theoretical approximation (loop order) considered for the calculation of the observables. This upper bound avoids subjective criteria for the "acceptable" level of EW fine-tuning for which the model is still "natural."

Ghilencea, D. M.

2014-05-01

270

Nature's Autonomous Oscillators  

NASA Technical Reports Server (NTRS)

Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature's observed autonomous oscillators, examples are the quasi-biennial oscillation and bimonthly oscillation of the Earth atmosphere, and the 22-year solar oscillation. The oscillations have been simulated in numerical models without external time dependent source, and in Section 2 we summarize the results. Specifically, we shall discuss the nonlinearities that are involved in generating the oscillations, and the processes that produce the periodicities. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity; Stretch-activation of muscle contraction is the mechanism that produces the high frequency oscillation of insect flight, discussed in Section 3. The same mechanism is also invoked to explain the functioning of the cardiac muscle. In Section 4, we present a tutorial review of the cardio-vascular system, heart anatomy, and muscle cell physiology, leading up to Starling's Law of the Heart, which supports our notion that the human heart is also a nonlinear oscillator. In Section 5, we offer a broad perspective of the tenuous links between the fluid dynamical oscillators and the human heart physiology.

Mayr, H. G.; Yee, J.-H.; Mayr, M.; Schnetzler, R.

2012-01-01

271

Natural gas conversion process  

SciTech Connect

The experimental apparatus was dismantled and transferred to a laboratory space provided by Lawrence Berkeley Laboratory (LBL) which is already equipped with a high-ventilation fume hood. This will enable us to make tests at higher gas flow rates in a safe environment. Three papers presented at the ACS meeting in San Francisco (Symposium on Natural Gas Upgrading II) April 5--10, 1992 show that the goal of direct catalytic conversion of Methane into heavier Hydrocarbons in a reducing atmosphere is actively pursued in three other different laboratories. There are similarities in their general concept with our own approach, but the temperature range of the experiments reported in these recent papers is much lower and this leads to uneconomic conversion rates. This illustrates the advantages of Methane activation by a Hydrogen plasma to reach commercial conversion rates. A preliminary process flow diagram was established for the Integrated Process, which was outlined in the previous Quarterly Report. The flow diagram also includes all the required auxiliary facilities for product separation and recycle of the unconverted feed as well as for the preparation and compression of the Syngas by-product.

Not Available

1992-01-01

272

Natural rubber latex allergy.  

PubMed

Natural rubber latex (NRL) is a ubiquitous allergen as it is a component of > 40,000 products in everyday life. Latex allergy might be attributed to skin contact or inhalation of latex particles. Latex allergy is an IgE-mediated hypersensitivity to NRL, presenting a wide range of clinical symptoms such as angioedema, swelling, cough, asthma, and anaphylactic reactions. Until 1979, latex allergy appeared only as type IV delayed hypersensitivity; subsequently, the proportion of different allergy types drifted towards type IV contact allergy reactions. Several risk factors for sensitization to NRL are already known and well documented. Some authors have established a positive correlation between a history of multiple surgical interventions, atopy, spina bifida malformation, and latex allergy incidence. We suspect an increase in latex allergy incidence in association with increased atopy and sensitivity to environmental allergens in the industrial population. It is often postulated in literature that the groups of workers at risk for this allergy are essentially workers in the latex industry and healthcare professionals. In this population, direct internal and mucosal contact with NRL medical devices may be the route of sensitization as factors such as the number of procedures and use of NRL materials (catheters and tubes) were associated with increased risk of latex sensitization and allergy. PMID:18797048

Deval, Ravi; Ramesh, V; Prasad, G B K S; Jain, Arun Kumar

2008-01-01

273

Freedom in nature  

NASA Astrophysics Data System (ADS)

The paper starts with the proposal that the cause of the apparent insolubility of the free-will problem are several popular but strongly metaphysical notions and hypotheses. To reduce the metaphysics, some ideas are borrowed from physics. A concept of event causality is discussed. The importance of Hume’s Principle of Causality is stressed and his Principle of Causation is weakened. The key concept of the paper, the so-called relative freedom, is also suggested by physics. It is a kind of freedom that can be observed everywhere in nature. Turning to biology, incomplete knowledge is defined for all organisms. They cope with the problem by Popper’s trial and error processes. One source of their success is the relative freedom of choice from the basic option ranges: mutations, motions and neural connections. Finally, the conjecture is adopted that communicability can be used as a criterion of consciousness and free will is defined as a conscious version of relative freedom. The resulting notion is logically self-consistent and it describes an observable phenomenon that agrees with our experience.

Hájí?ek, P.

2009-09-01

274

Nature, nurture, and expertise  

PubMed Central

Rather than investigating the extent to which training can improve performance under experimental conditions (‘what could be’), we ask about the origins of expertise as it exists in the world (‘what is’). We used the twin method to investigate the genetic and environmental origins of exceptional performance in reading, a skill that is a major focus of educational training in the early school years. Selecting reading experts as the top 5% from a sample of 10,000 12-year-old twins assessed on a battery of reading tests, three findings stand out. First, we found that genetic factors account for more than half of the difference in performance between expert and normal readers. Second, our results suggest that reading expertise is the quantitative extreme of the same genetic and environmental factors that affect reading performance for normal readers. Third, growing up in the same family and attending the same schools account for less than a fifth of the difference between expert and normal readers. We discuss implications and interpretations (‘what is inherited is DNA sequence variation’; ‘the abnormal is normal’). Finally, although there is no necessary relationship between ‘what is’ and ‘what could be’, the most far-reaching issues about the acquisition of expertise lie at the interface between them (‘the nature of nurture: from a passive model of imposed environments to an active model of shaped experience’).

Plomin, Robert; Shakeshaft, Nicholas G.; McMillan, Andrew; Trzaskowski, Maciej

2014-01-01

275

Methylgermanium in natural waters  

NASA Astrophysics Data System (ADS)

Biological methylation of metallic elements1 and the occurrence and cycling of organometals in the environment have been investigated in Japan during the 1950s and 1960s, where the ingestion of fish and shellfish contaminated with methylmercury compounds caused mercury poisoning2,3. Biomethylation ability has been demonstrated in bacteria, fungi and algae for As, Cd, Hg, Pb, Se, Sn, Te and Tl4-7. Naturally-occurring methylated species have been reported in estuaries and seawater for Sb8, As9, Ge10-13 and Sn14, although recent evidence suggests that some reports of methyltin species result from interferences by Ge and volatile sulphur compounds15. With the exception of Sb8, As9,12,16 and Ge11,12, there are no consistent estuarine or oceanic profiles for methylmetal compounds in the literature from which to judge their biogeochemical behaviour. Early investigations17-19 reported that methylgermanium species do not exist in the aquatic environment. Subsequently, we identified monomethylgermanium (MMGe) and dimethylgermanium (DMGe) in estuaries10,12, the Baltic Sea11 and the Bering and Sargasso seas13. We report here recent measurements of methylgermanium compounds in river water, estuaries, seawater and anoxic basins.

Lewis, Brent L.; Froelich, Philip N.; Andreae, Meinrat O.

1985-01-01

276

A natural topological insulator.  

PubMed

The earth's crust and outer space are rich sources of technologically relevant materials which have found application in a wide range of fields. Well-established examples are diamond, one of the hardest known materials, or graphite as a suitable precursor of graphene. The ongoing drive to discover novel materials useful for (opto)electronic applications has recently drawn strong attention to topological insulators. Here, we report that Kawazulite, a mineral with the approximate composition Bi2(Te,Se)2(Se,S), represents a naturally occurring topological insulator whose electronic properties compete well with those of its synthetic counterparts. Kawazulite flakes with a thickness of a few tens of nanometers were prepared by mechanical exfoliation. They exhibit a low intrinsic bulk doping level and correspondingly a sizable mobility of surface state carriers of more than 1000 cm(2)/(V s) at low temperature. Based on these findings, further minerals which due to their minimized defect densities display even better electronic characteristics may be identified in the future. PMID:23438015

Gehring, P; Benia, H M; Weng, Y; Dinnebier, R; Ast, C R; Burghard, M; Kern, K

2013-03-13

277

Naturalness and supersymmetry  

SciTech Connect

In this thesis, the author argues that the supersymmetric Standard Model, while avoiding the fine tuning in electroweak symmetry breaking, requires unnaturalness/fine tuning in some (other) sector of the theory. For example, Baryon and Lepton number violating operators are allowed which lead to proton decay and flavor changing neutral currents. He studies some of the constraints from the latter in this thesis. He has to impose an R-parity for the theory to be both natural and viable. In the absence of flavor symmetries, the supersymmetry breaking masses for the squarks and sleptons lead to too large flavor changing neutral currents. He shows that two of the solutions to this problem, gauge mediation of supersymmetry breaking and making the scalars of the first two generations heavier than a few TeV, reintroduce fine tuning in electroweak symmetry breaking. He also constructs a model of low energy gauge mediation with a non-minimal messenger sector which improves the fine tuning and also generates required Higgs mass terms. He shows that this model can be derived from a Grand Unified Theory despite the non-minimal spectrum.

Agashe, K. [Lawrence Berkeley National Lab., CA (United States). Theoretical Physics Group]|[Univ. of California, Berkeley, CA (United States). Dept. of Physics

1998-05-01

278

Nature of Human Error  

PubMed Central

Background: As the attitude to adverse events has changed from the defensive “blame and shame culture” to an open and transparent healthcare delivery system, it is timely to examine the nature of human errors and their impact on the quality of surgical health care. Methods: The approach of the review is generic rather than specific, and the account is based on the published psychologic and medical literature on the subject. Conclusions: Rather than detailing the various “surgical errors,” the concept of error categories within the surgical setting committed by surgeons as front-line operators is discussed. The important components of safe surgical practice identified include organizational structure with strategic control of healthcare delivery, teamwork and leadership, evidence-based practice, proficiency, continued professional development of all staff, availability of wireless health information technology, and well-embedded incident reporting and adverse events disclosure systems. In our quest for the safest possible surgical health care, there is a need for prospective observational multidisciplinary (surgeons and human factors specialists) studies as distinct for retrospective reports of adverse events. There is also need for research to establish the ideal system architecture for anonymous reporting of near miss and no harm events in surgical practice.

Cuschieri, Alfred

2006-01-01

279

Nature of orchestral noise.  

PubMed

Professional orchestral musicians are at risk of exposure to excessive noise when at work. This is an industry-wide problem that threatens not only the hearing of orchestral musicians but also the way orchestras operate. The research described in this paper recorded noise levels within a professional orchestra over three years in order to provide greater insight to the orchestral noise environment; to guide future research into orchestral noise management and hearing conservation strategies; and to provide a basis for the future education of musicians and their managers. Every rehearsal, performance, and recording from May 2004 to May 2007 was monitored, with the woodwind, brass, and percussion sections monitored in greatest detail. The study recorded dBALEQ and dBC peak data, which are presented in graphical form with accompanying summarized data tables. The findings indicate that the principal trumpet, first and third horns, and principal trombone are at greatest risk of exposure to excessive sustained noise levels and that the percussion and timpani are at greatest risk of exposure to excessive peak noise levels. However, the findings also strongly support the notion that the true nature of orchestral noise is a great deal more complex than this simple statement would imply. PMID:18681585

O'Brien, Ian; Wilson, Wayne; Bradley, Andrew

2008-08-01

280

Rheological properties of maleated natural rubber and natural rubber blends  

Microsoft Academic Search

Two types of natural rubber (ADS and STR 5L) were used to prepare maleated natural rubber (MNR). Melt rheological properties of MNRs (i.e. MNR-ADS and MNR-STR) and their blends with the same type of natural rubber were quantified. We found that the Mooney viscosities of MNR-ADS\\/ADS blends were higher than those of MNR-STR\\/STR 5L blends. The log additive rule was

C Nakason; A Kaesaman; Z Samoh; S Homsin; S Kiatkamjornwong

2002-01-01

281

The Nature of Naive Explanations of Natural Selection.  

ERIC Educational Resources Information Center

Suggests that misconceptions about natural selection arise from mistaken categorization. Proposes that students often fail to understand the ontological features of equilibrium processes. Contains 32 references. (DDR)

Ferrari, Michel; Chi, Michelene T. H.

1998-01-01

282

Nature's Palette: The Search for Natural Blue Colorants.  

PubMed

The food and beverage industry is seeking to broaden the palette of naturally derived colorants. Although considerable effort has been devoted to the search for new blue colorants in fruits and vegetables, less attention has been directed toward blue compounds from other sources such as bacteria and fungi. The current work reviews known organic blue compounds from natural plant, animal, fungal, and microbial sources. The scarcity of blue-colored metabolites in the natural world relative to metabolites of other colors is discussed, and structural trends common among natural blue compounds are identified. These compounds are grouped into seven structural classes and evaluated for their potential as new color additives. PMID:24930897

Newsome, Andrew G; Culver, Catherine A; van Breemen, Richard B

2014-07-16

283

Alveolar Echinococcosis: Characterization of Diagnostic Antigen Em18 and Serological Evaluation of Recombinant Em18  

PubMed Central

The Echinococcus multilocularis protein Em18 is one of the most promising antigens for use in serodiagnosis of alveolar echinococcosis in human patients. Here we identify an antigenic relationship between Em18 and a 65-kDa immunodominant E. multilocularis surface protein previously identified as either EM10 or EmII/3. The NH2-terminal sequence of native Em18 was determined, revealing it to be a fragment of EM10. Experiments were undertaken to investigate the effect of proteinase inhibitors on the degradation of EM10 in crude extracts of E. multilocularis protoscoleces. Em18 was found to be the product of degradation of EM10 by cysteine proteinase. A recombinant Em18 (RecEm18, derived from 349K to 508K of EM10) was successfully expressed by using Escherichia coli expression system and then evaluated for use in serodiagnosis of alveolar echinococcosis. RecEm18 was recognized by 27 (87.1%) and 28 (90.3%) of 31 serum samples from clinically and/or pathologically confirmed alveolar echinococcosis patients by enzyme-linked immunosorbent assay and immunoblotting, respectively. Of 33 serum samples from cystic echinococcosis patients, 1 was recorded as having a weak positive reaction to RecEm18; however, none of the serum samples which were tested from neurocysticercosis patients (n = 10) or healthy people (n = 15) showed positive reactions. RecEm18 has the potential for use in the differential serodiagnosis of alveolar echinococcosis.

Sako, Yasuhito; Nakao, Minoru; Nakaya, Kazuhiro; Yamasaki, Hiroshi; Gottstein, Bruno; Lightowers, Marshall W.; Schantz, Peter M.; Ito, Akira

2002-01-01

284

Generalized EM-type reconstruction algorithms for emission tomography.  

PubMed

We provide a general form for many reconstruction estimators of emission tomography. These estimators include Shepp and Vardi's maximum likelihood (ML) estimator, the quadratic weighted least squares (WLS) estimator, Anderson's WLS estimator, and Liu and Wang's multi-objective estimator, and others. We derive a generic update rule by constructing a surrogate function. This work is inspired by the ML-EM (EM, expectation maximization), where the latter naturally arises as a special case. A regularization with a specific form can also be incorporated by De Pierro's trick. We provide a general and quite different convergence proof compared with the proofs of the ML-EM and De Pierro. Theoretical analysis shows that the proposed algorithm monotonically decreases the cost function and automatically meets nonnegativity constraints. We have introduced a mechanism to provide monotonic, self-constraining, and convergent algorithms, from which some interesting existing and new algorithms can be derived. Simulation results illustrate the behavior of these algorithms in term of image quality and resolution-noise tradeoff. PMID:22665503

Teng, Yueyang; Zhang, Tie

2012-09-01

285

Natural-gas price puzzle  

Microsoft Academic Search

Rectifying natural-gas underpricing and distortions in production has benefited the overall economy, but transition costs are large, and problems and strains continue. The natural-gas price story began with the 1954 price controls that developed into a wasteful, inefficient, and unfair system of too-low gas prices that resulted in the 1978 Natural Gas Policy Act (NGPA). While meeting a number of

1983-01-01

286

Natural gas monthly, September 1998  

SciTech Connect

The National Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. 6 figs., 27 tabs.

NONE

1998-09-01

287

Natural gas monthly, February 1996  

SciTech Connect

The NGM highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

NONE

1996-03-01

288

Natural gas monthly, January 1994  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. The featured article for this month is on US coalbed methane production.

Not Available

1994-02-01

289

Natural Products as Aromatase Inhibitors  

PubMed Central

With the clinical success of several synthetic aromatase inhibitors (AIs) in the treatment of postmenopausal estrogen receptor-positive breast cancer, researchers have also been investigating also the potential of natural products as AIs. Natural products from terrestrial and marine organisms provide a chemically diverse array of compounds not always available through current synthetic chemistry techniques. Natural products that have been used traditionally for nutritional or medicinal purposes (e.g., botanical dietary supplements) may also afford AIs with reduced side effects. A thorough review of the literature regarding natural product extracts and secondary metabolites of plant, microbial, and marine origin that have been shown to exhibit aromatase inhibitory activity is presented herein.

Balunas, Marcy J.; Su, Bin; Brueggemeier, Robert W.; Kinghorn, A. Douglas

2010-01-01

290

Natural Products as Molecular Messengers*  

PubMed Central

The chemistry of naturally-occurring compounds has long been pursued in the search for medicines, dyes, pesticides, flavors, and fragrances. In addition, the deeper aim of understanding life itself as a chemical phenomenon has motivated generations of scientists. One consequence of such studies has been the realization that natural products often serve central roles as biological signaling agents. We consider natural products from the viewpoint of the organisms that produce and/or respond to them, and suggest how a naturally-occurring compound may acquire its role in chemical communication.

Meinwald, Jerrold

2011-01-01

291

The Nature Conservancy--Saving North Carolina's Natural Treasures.  

ERIC Educational Resources Information Center

Discusses the North Carolina branch of The Nature Conservancy and its efforts to preserve natural areas Camping and Outdoor Education; University of North Carolina Damping and Outdoor Education; University of North Carolina at Greensboro; Pine Lake Field Campus; 4016 Blumenthal Road; Greensboro, NC, 27406. (AN)

Annand, Fred

1980-01-01

292

Nature of deleterious mutation load in Drosophila.  

PubMed

Much population genetics and evolution theory depends on knowledge of genomic mutation rates and distributions of mutation effects for fitness, but most information comes from a few mutation accumulation experiments in Drosophila in which replicated chromosomes are sheltered from natural selection by a balancer chromosome. I show here that data from these experiments imply the existence of a large class of minor viability mutations with approximately equivalent effects. However, analysis of the distribution of viabilities of chromosomes exposed to EMS mutagenesis reveals a qualitatively different distribution of effects lacking such a minor effects class. A possible explanation for this difference is that transposable element insertions, a common class of spontaneous mutation event in Drosophila frequently generate minor viability effects. This explanation would imply that current estimates of deleterious mutation rates are not generally applicable in evolutionary models, as transposition rates vary widely. Alternatively, much of the apparent decline in viability under spontaneous mutation accumulation could have been nonmutational, perhaps due to selective improvement of balancer chromosomes. This explanation accords well with the data and implies a spontaneous mutation rate for viability two orders of magnitude lower than previously assumed, with most mutation load attributable to major effects. PMID:8978082

Keightley, P D

1996-12-01

293

Žem?s dangos skaitmenini? vaizd? identifikavimo analiz?  

NASA Astrophysics Data System (ADS)

Straipsnyje nagrin?jamas žem?s dangos skaitmenini? vaizd? identifikavimas taikant kovariacini? funkcij? ir Wavelet (bang?) teorij?. Dviej? skaitmenini? vaizd? arba pavieni? vaizd? autokovariacini? funkcij? ?ver?iai skai?iuojami pagal atsitiktines funkcijas, sudarytas iš skaitmenini? vaizd? pikseli? vektori? pavidalu. Pikseli? vektori? ?ver?iai gaunami skleidžiant skaitmenini? vaizd? pikseli? masyvus viena eilute. Tyrimams panaudoti HJ-DEM Ikonos palydoviniai vaizdai, kai kartografin? projekcija n?ra ortografin?, ir skaitmeninio vaizdo ta\\vsk? masteliai skirtingi. Kei?iant skaitmeninio vaizdo mastel? pavieni? pikseli? spalv? bang? dažniai lieka nekintantys, t. y. const, ir kovariacini? funkcij? skai?iavimo proced?rose mastelio kaitos ?taka nepasirei\\vskia. Vaizdams identifikuoti taikytas RGB formato spalv? spektras. Analizuota RGB spektro dedam?j? bei spalv? tenzoriaus ?taka skaitmenini? vaizd? kovariacini? funkcij? ?ver?iams. Skaitmenini? vaizd? tapatumas ?vertinamas pagal koreliacijos koeficient? reikšmi? kait? atitinkam? reikšmi? diapazone, taikant sudaryt? kompiuterin? program?.

Skeivalas, Jonas; Aleknien?, Edita; Ge?yt?, Silvija

2010-01-01

294

NATURAL EMISSIONS OF OXIDANT PRECURSORS  

EPA Science Inventory

This paper provides an overview of the sources, the estimation methodology, and the relative amounts of natural hydrocarbon and nitrogen oxide emissions. he most recent estimate of natural nonmethane hydrocarbon (NMHC) emissions for the United States is 28 teragrams per year (Tg/...

295

Is Banking a Natural Monopoly?  

Microsoft Academic Search

This paper reviews the arguments behind claims that banking is a natural monopoly. There are economies in reserve-holding and asset diversification, but the marginal return to scale tends to fall as the bank grows, and there is not particular reason to expect these economies to be large enough to produce a natural monopoly. The paper then examines three spurious arguments

Kevin Dowd

1992-01-01

296

Natural Gas Industry and Markets  

EIA Publications

This special report provides an overview of the supply and disposition of natural gas in 2004 and is intended as a supplement to the Energy Information Administration's (EIA) Natural Gas Annual 2004 (NGA). Unless otherwise stated, all data and figures in this report are based on summary statistics published in the NGA 2004.

Information Center

2006-03-03

297

The surface learned from nature  

Microsoft Academic Search

In this work, I would like to introduce the emerging surface of nature. The surface in nature, has the multi and optimized function with well organized structure. There are so many examples that we learn and apply to technology. First example is self-cleaning surface. Some plants (such as lotus leaf, taro leaf) and the wings of many large-winged insects (such

H. Lim; W. D. Kim

2010-01-01

298

Natural gas in North Dakota  

Microsoft Academic Search

Almost all natural gas produced in North Dakota is casinghead gas from oil pools in the Madison group along the Nesson anticline and from pools in Burke County. Relatively minor quantities of dry gas are produced from the gas fields of North Dakota part of the Cedar Creek anticline. Only the natural gas from these areas is used commercially; the

S. B. Anderson; W. P. Eastwood

1968-01-01

299

Natural Resources and State Fragility  

Microsoft Academic Search

This paper provides an overview of the relationships between natural resources, governance, and economic performance. The relationships run in both directions, with resources potentially altering the quality of governance, and governance being particularly important for resource poor countries. Both these relationships have threshold effects; if governance quality is above some level then natural resources can lead to further improvement, while

Paul Collier; Anthony J. Venables

2009-01-01

300

Massachusetts Natural Valley Storage Investigation.  

National Technical Information Service (NTIS)

The goal of this study was to research and discuss methodologies to quantify in economic terms the costs and benefits of natural valley storage as a means of reducing future flood damages. Natural valley storage consist of wetlands and floodplains which p...

1993-01-01

301

Commentary: Biochemistry Re-Natured  

ERIC Educational Resources Information Center

In his last commentary on "Biochemistry Denatured," this author dealt with his perception that college students today have spent too little of their childhood years playing outside in nature and as a consequence have not learned basic things about the world from personal experience. This "nature-deficit disorder" removes many opportunities for…

White, Harold B.

2010-01-01

302

Natural Killer Cells in Psoriasis  

Microsoft Academic Search

Psoriasis is one of the most common immune-mediated disorders. There is evidence that it is mediated by Th1 and, more recently, Th17 cells. The cytokine pattern, particularly the dominance of TNF-?, implicates the innate immune system in psoriasis pathogenesis. Of the many components of the innate immune system known to be involved in psoriatic lesions, natural killer and natural killer

A. M. Tobin; L. Lynch; B. Kirby; C. O’Farrelly

2011-01-01

303

Natural Decrease in Texas Counties.  

ERIC Educational Resources Information Center

In replication of other studies, the natural decrease of Texas population was examined in terms of the effect of migration and fertility. Utilizing Texas and U.S. vital statistics and the 1970 U.S. Census of Population, Texas population trends were analyzed for the 1968-72 period by dividing the 254 Texas counties into: (1) 65 natural decrease…

Koebernick, Thomas E.; Markides, Kyriakos S.

304

Climate Change: Prospects for Nature  

SciTech Connect

Thomas Lovejoy, President of The H. John Heinz III Center for Science, Economics and the Environment, explores the impact of climate change on the natural world. He also discusses the implications of climate change for climate policy and natural resource management.

Thomas Lovejoy

2008-03-12

305

The Norwegian Nature Life Approach.  

ERIC Educational Resources Information Center

Briefly introduces the Norwegian Seminar for Nature Life with a discussion of the course methods, values, and attitudes as related to Norwegian culture. Explains the difference between this and other programs that use nature for experiential education, and addresses the need for creativity in experiential education. (SB)

Pendleton, Sarah

1983-01-01

306

Natural Selection: How Evolution Works  

NSDL National Science Digital Library

The issue-focused interview demonstrates how natural selection is a very efficient, predictable mechanism of evolution. It illustrates how species adapt to their environment, the reproductive success of a species, design in nature and presents evidence of evolution in action, e.g., antibiotic resistance.

Douglas Futuyma (State University of New York at Stony Brook;)

2004-12-01

307

Natural Gas Imports and Exports  

EIA Publications

In the face of unprecedented levels of domestic natural gas production, net imports of natural gas into the United States fell 23% in 2012. A combination of both higher exports and lower imports led to a decline in net imports. In 2012, total imports decreased by 10% to 3,135 Bcf, while total exports increased by 8% to 1,619 Bcf.

2013-07-23

308

Czech Children's Drawing of Nature  

ERIC Educational Resources Information Center

Do world children draw nature pictures in a certain way? Range of mountains in the background, a sun, couple clouds, a river rising from mountains. Is this type of drawing universal in the way these nature items are organized on a drawing paper? The sample size from Czech Republic included 33 participants from two kindergartens. They were 5 and 6…

Yilmaz, Zuhal; Kubiatko, Milan; Topal, Hatice

2012-01-01

309

Natural Gas Energy Educational Kit.  

ERIC Educational Resources Information Center

Prepared by energy experts and educators to introduce middle school and high school students to natural gas and its role in our society, this kit is designed to be incorporated into existing science and social studies curricula. The materials and activities focus on the origin, discovery, production, delivery, and use of natural gas. The role of…

American Gas Association, Arlington, VA. Educational Services.

310

Understanding Natural Gas Price Decontrol.  

National Technical Information Service (NTIS)

In 1978, the Congress passed the Natural Gas Policy Act (NGPA), which allowed gradual increases in the price of natural gas at the wellhead. The legislation sought to raise the price of most gas to the equivalent of the act's projected price of oil by 198...

1983-01-01

311

Illinois Birds. Nature Discovery I.  

ERIC Educational Resources Information Center

The birds of Illinois and their particular habitats are explored in this guide which is a part of a series of Nature Discovery publications. The materials are designed to directly supplement the natural science curricula and to complement other subject areas including social studies, language arts, music, and art. The program is formated for…

Stone, Sally F.

312

Climate Change: Prospects for Nature  

ScienceCinema

Thomas Lovejoy, President of The H. John Heinz III Center for Science, Economics and the Environment, explores the impact of climate change on the natural world. He also discusses the implications of climate change for climate policy and natural resource management.

313

34 CFR 303.26 - Natural environments.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Natural environments. 303.26 Section 303.26 Education...Definitions Used in This Part § 303.26 Natural environments. Natural environments means settings that are natural or...

2013-07-01

314

Natural gas monthly - January 1996  

SciTech Connect

This highlight discusses changes in natural gas supply, demand, and prices for the first three quarters of 1995 (January thru September) compared to the same periods in 1993 and 1994. Production for the first three quarters of 1995 lagged year-earlier levels while natural gas consumption has continued a steady upward movement. Total U.S. natural gas production through the first three quarters at 14.1 trillion cubic feet, was less than 1 percent below the 1994 period, but remained well ahead of the comparable 1993 period. The three leading producing States (Texas, Louisiana, and Oklahoma) contributed nearly 70 percent of the total. Natural gas consumption totaled 16.0 trillion cubic feet for the first three quarters, 4 percent above the same period in 1994. Net imports of natural gas reached 2.0 trillion cubic feet by the end of the third quarter 1995 and accounted for nearly 13 percent of total consumption during this period.

NONE

1996-01-01

315

Multicellular microorganisms: laboratory versus nature  

PubMed Central

Our present in-depth knowledge of the physiology and regulatory mechanisms of microorganisms has arisen from our ability to remove them from their natural, complex ecosystems into pure liquid cultures. These cultures are grown under optimized laboratory conditions and allow us to study microorganisms as individuals. However, microorganisms naturally grow in conditions that are far from optimal, which causes them to become organized into multicellular communities that are better protected against the harmful environment. Moreover, this multicellular existence allows individual cells to differentiate and acquire specific properties, such as forming resistant spores, which benefit the whole population. The relocation of natural microorganisms to the laboratory can result in their adaptation to these favourable conditions, which is accompanied by complex changes that include the repression of some protective mechanisms that are essential in nature. Laboratory microorganisms that have been cultured for long periods under optimized conditions might therefore differ markedly from those that exist in natural ecosystems.

Palkova, Zdena

2004-01-01

316

Natural gas pipeline technology overview.  

SciTech Connect

The United States relies on natural gas for one-quarter of its energy needs. In 2001 alone, the nation consumed 21.5 trillion cubic feet of natural gas. A large portion of natural gas pipeline capacity within the United States is directed from major production areas in Texas and Louisiana, Wyoming, and other states to markets in the western, eastern, and midwestern regions of the country. In the past 10 years, increasing levels of gas from Canada have also been brought into these markets (EIA 2007). The United States has several major natural gas production basins and an extensive natural gas pipeline network, with almost 95% of U.S. natural gas imports coming from Canada. At present, the gas pipeline infrastructure is more developed between Canada and the United States than between Mexico and the United States. Gas flows from Canada to the United States through several major pipelines feeding U.S. markets in the Midwest, Northeast, Pacific Northwest, and California. Some key examples are the Alliance Pipeline, the Northern Border Pipeline, the Maritimes & Northeast Pipeline, the TransCanada Pipeline System, and Westcoast Energy pipelines. Major connections join Texas and northeastern Mexico, with additional connections to Arizona and between California and Baja California, Mexico (INGAA 2007). Of the natural gas consumed in the United States, 85% is produced domestically. Figure 1.1-1 shows the complex North American natural gas network. The pipeline transmission system--the 'interstate highway' for natural gas--consists of 180,000 miles of high-strength steel pipe varying in diameter, normally between 30 and 36 inches in diameter. The primary function of the transmission pipeline company is to move huge amounts of natural gas thousands of miles from producing regions to local natural gas utility delivery points. These delivery points, called 'city gate stations', are usually owned by distribution companies, although some are owned by transmission companies. Compressor stations at required distances boost the pressure that is lost through friction as the gas moves through the steel pipes (EPA 2000). The natural gas system is generally described in terms of production, processing and purification, transmission and storage, and distribution (NaturalGas.org 2004b). Figure 1.1-2 shows a schematic of the system through transmission. This report focuses on the transmission pipeline, compressor stations, and city gates.

Folga, S. M.; Decision and Information Sciences

2007-11-01

317

The Science of Middle Nature  

NASA Astrophysics Data System (ADS)

In the field of biogeochemistry, urbanization is often considered as an "alteration" or "disturbance" to the earth's surface and its natural processes. This view is an outcome of the view of nature inherent in earth system science and ecology, in which nature is defined as separate from humans and society. However, other disciplines are based in alternative views of nature in which humans are more integral components of the landscape. Urban planning, landscape architecture, agriculture, and horticulture, for example, more fully integrate the role of landscape design and management in the functioning of human-dominated ecosystems. We suggest that the field of urban biogeochemistry has been somewhat limited by the predominant, disturbance-based view of the role of nature in cities, and that more deeply evaluating and broadening the concept of nature inherent in studies of urban processes can enhance our understanding of the role of urbanization in the earth system. A particularly useful concept is the "middle nature" proposed by Cosgrove (1993), which serves a purpose of "actively transforming nature into culture." It is this view of urban landscapes as middle nature, or transformation of urban space into human-dominated nature with a purpose, that is lacking from the current scientific discourse about the role of biogeochemistry in urban ecosystem services. A scientific evaluation of middle nature implies studying the performance of urban designs to meet intended cultural and environmental goals, including beauty, social equity, governance, and social capital as well as environmental quality. We describe our work in evaluating the transformed urban landscapes of Los Angeles from multiple perspectives that focus on urban livability, equity, and beauty as well as the physical impacts of plants and soils on the environment. The outcomes of this process do not necessary meet the traditional demands of biophysical ecology such as utilizing native species, maximizing carbon sequestration, or minimizing human disturbance. Rather, in our project the discourse is shifting away from the ecosystem services framework, and towards a shared vision for middle nature as the intersection between nature as we have traditionally valued it outside of the city, and its integral role in urban culture, design, function, and quality of life.

Pataki, D. E.; Pincetl, S.

2012-12-01

318

Understanding the benign nature of SIV infection in natural hosts  

PubMed Central

In striking contrast to HIV infection, natural SIV infection of African nonhuman primates is asymptomatic and usually does not induce significant CD4+ T cell depletion despite high levels of virus replication. Recently, significant progress has been made in understanding the mechanisms underlying the remarkable difference in infection outcome between natural and nonnatural HIV/SIV hosts. These advances include the identification of limited immune activation as a key factor protecting natural SIV hosts from AIDS and the discovery of low CC chemokine receptor 5 expression on CD4+ T cells as a specific and consistent immunologic feature in these animals. Further elucidation of the pathways by which the differences in immune activation between natural and nonnatural hosts are manifest holds promise for the design of novel therapeutic approaches to HIV infection.

Silvestri, Guido; Paiardini, Mirko; Pandrea, Ivona; Lederman, Michael M.; Sodora, Donald L.

2007-01-01

319

Natural Gas Prices Forecast Comparison AEO vs. Natural Gas Markets.  

National Technical Information Service (NTIS)

This paper evaluates the accuracy of two methods to forecast natural gas prices: using the Energy Information Administration's Annual Energy Outlook forecasted price (AEO) and the Henry Hub compared to U.S. Wellhead futures price. A statistical analysis i...

G. Wong-Parodi A. Lekov L. Dale

2004-01-01

320

Natural gas monthly, February 1998  

SciTech Connect

This issue of the Natural Gas Monthly (NGM) presents the most recent estimates of natural gas data from the Energy Information Administration. Estimates extend through February 1998 for many data series, and through November 1997 for most natural gas prices. Highlights of the natural gas data contained in this issue are: Preliminary estimates for January and February 1998 show that dry natural gas production, net imports, and consumption are all within 1 percent of their levels in 1997. Warmer-than-normal weather in recent months has resulted in lower consumption of natural gas by the residential sector and lower net withdrawals of gas from under round storage facilities compared with a year ago. This has resulted in an estimate of the amount of working gas in storage at the end of February 1998 that is 18 percent higher than in February 1997. The national average natural gas wellhead price is estimated to be $3.05 per thousand cubic feet in November 1997, 7 percent higher than in October. The cumulative average wellhead price for January through November 1997 is estimated to be $2.42 per thousand cubic feet, 17 percent above that of the same period in 1996. This price increase is far less than 36-percent rise that occurred between 1995 and 1996. 6 figs., 26 tabs.

NONE

1998-02-01

321

The Nature of US Natural Hazards Research, 1988-2008  

NASA Astrophysics Data System (ADS)

Numerous academic disciplines have contributed to the body of published research on natural hazards and disasters. Geologists, engineers, geographers, and sociologists have participated since the topic first emerged as a formal research agenda in the early 1950s. In more recent decades, psychologists, political scientists, economists, historians, archeologists, anthropologists, architects, computer scientists, and artists have added to our understanding of environmental risk, hazard, and disaster. When examined in-print, what are the discipline-demographics of natural hazards? Who contributes and who tends to have the greater influence on scholarly discourse related to the topic? Are there clear trends in methods, techniques, or paradigmatic approaches? To what degree does this inherently interdisciplinary topic render interdisciplinary research? This paper will present initial findings from a larger data set on natural hazards and social science research. We will describe the discipline-demographics of natural hazards scholarship by examining college-level texts, peer-reviewed journal publications, federally-funded reports, and federally-funded research grants relating to natural hazards or disasters from 1988 to 2008. The citation frequency of sampled references will also be examined as a surrogate for influence on the scholarly discourse of natural hazards. In this paper, we will focus attention on the contributions of social scientists during this period, including an assessment of temporal trends relative to specific disaster events.

Hagelman, R., III

2009-04-01

322

Natural Fiber Composites: A Review  

SciTech Connect

The need for renewable fiber reinforced composites has never been as prevalent as it currently is. Natural fibers offer both cost savings and a reduction in density when compared to glass fibers. Though the strength of natural fibers is not as great as glass, the specific properties are comparable. Currently natural fiber composites have two issues that need to be addressed: resin compatibility and water absorption. The following preliminary research has investigated the use of Kenaf, Hibiscus cannabinus, as a possible glass replacement in fiber reinforced composites.

Westman, Matthew P.; Fifield, Leonard S.; Simmons, Kevin L.; Laddha, Sachin; Kafentzis, Tyler A.

2010-03-07

323

Natural attenuation of contaminated soils.  

PubMed

Natural attenuation is increasing in use as a low cost means of remediating contaminated soil and groundwater. Modelling of contaminant migration plays a key role in evaluating natural attenuation as a remediation option and in ensuring that there will be no adverse impact on humans and the environment. During natural attenuation, the contamination must be characterized thoroughly and monitored through the process. In this paper, attenuation mechanisms for both organic and inorganic contaminants, use of models and protocols, role of monitoring and field case studies will be reviewed. PMID:15031019

Mulligan, Catherine N; Yong, Raymond N

2004-06-01

324

Neural processing of natural sounds.  

PubMed

We might be forced to listen to a high-frequency tone at our audiologist's office or we might enjoy falling asleep with a white-noise machine, but the sounds that really matter to us are the voices of our companions or music from our favourite radio station. The auditory system has evolved to process behaviourally relevant natural sounds. Research has shown not only that our brain is optimized for natural hearing tasks but also that using natural sounds to probe the auditory system is the best way to understand the neural computations that enable us to comprehend speech or appreciate music. PMID:24840800

Theunissen, Frédéric E; Elie, Julie E

2014-05-20

325

Avaliação dos efeitos centrais dos fl orais de Bach em camundongos através de modelos farmacológicos específi cos  

Microsoft Academic Search

RESUMO: Os Remédios Florais de Bach (RFB), constituem um método alternativo de tratamento usado largamente na terapêutica de várias patologias em muitos países do mundo. Os RFB são reconhecidos como tratamento natural pela OMS desde 1956. Embora o mecanismo de ação dos RFB ainda não tenha sido elucidado, eles vêm sendo indicados para o tratamento de várias doenças neuropsiquiátricas. O

Márcia M. De-Souza; Milene Garbeloto; Karin Denez; Iriane Eger-Mangrich

326

Deterministini? ir geostatistini? interpoliavimo metod? taikymas Žem?s paviršiui modeliuoti  

NASA Astrophysics Data System (ADS)

Analizuojamas Žem?s paviršiaus trimatis modeliavimas pagal geodezinius ir fotogrametrinius matavimo duomenis, taikant tiesin?, svorin? ir Kriging interpoliavimo metodus. Interpoliavimo algoritmai pertvarkyti ir pritaikyti MATLAB paketo vykdomajam kodui. Sudarytoji programa Geo3D skirta erdviniams duomenims vaizduoti pagal geodezinius ir fotogrametrinius duomenis. Geo3D programa sudaryti trima?iai Žem?s paviršiaus modeliai ?vertinti bei palyginti su modeliais, sukurtais reljefo vaizdavimo programa WinSurf.

Nareiko, Viktor; Ruzgien?, Birut?; ?selis, Adomas

2010-01-01

327

Three-wave mixing of volume EM, surface EM and surface acoustic waves  

Microsoft Academic Search

The authors have investigated the diffraction of volume EM waves into surface EM waves (or vice versa) by surface acoustic (SA) waves, i.e. the three-wave mixing of volume EM, surface EM and SA waves, using a Kretschmann (prism\\/Ag film\\/air) configuration with the SA waves propagating in the Ag film. The diffraction intensity was measured as a function of the angle

H. Talaat; W. P. Chen; E. Burstein

1982-01-01

328

Compressed natural gas measurement issues  

SciTech Connect

The Natural Gas Vehicle Coalition`s Measurement and Metering Task Group (MMTG) was established on July 1st, 1992 to develop suggested revisions to National Institute of Standards & Technology (NIST) Handbook 44-1992 (Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices) and NIST Handbook 130-1991 (Uniform Laws & Regulations). Specifically, the suggested revisions will address the sale and measurement of compressed natural gas when sold as a motor vehicle fuel. This paper briefly discusses the activities of the MMTG and its interaction with NIST. The paper also discusses the Institute of Gas Technology`s (IGT) support of the MMTG in the area of natural gas composition, their impact on metering technology applicable to high pressure fueling stations as well as conversion factors for the establishment of ``gallon gasoline equivalent`` of natural gas. The final portion of this paper discusses IGT`s meter research activities and its meter test facility.

Blazek, C.F.; Kinast, J.A.; Freeman, P.M.

1993-12-31

329

Natural and Artificial Parallel Computation.  

National Technical Information Service (NTIS)

Contents: The Nature of Parallel Programming; Applications of Parallel Supercomputers: Scientific Results and Computer Science Lessons; Towards General-Purpose Parallel Computers; Cooperative Computation in Brains and Computers; Parallel Systems in the Ce...

O. Simula

1992-01-01

330

Major natural disaster afteraction assessment.  

National Technical Information Service (NTIS)

In recent years, a wide variety of natural disasters has disrupted energy supplies. Some incidents occurred in the continental US, others in offshore US territory, and still others in foreign countries. Each locale provided a unique backdrop against which...

1991-01-01

331

A quantum of natural selection  

NASA Astrophysics Data System (ADS)

The modern evolutionary synthesis, which marries Darwin's theory of natural selection with Mendel's genetics, was developed around the same time as quantum mechanics. Is there any connection between the two?

Lloyd, Seth

2009-03-01

332

Thermal loading of natural streams  

USGS Publications Warehouse

The impact of thermal loading on the temperature regime of natural streams is investigated by mathematical models, which describe both transport (convection-diffusion) and decay (surface dissipation) of waste heat over 1-hour or shorter time intervals. The models are derived from the principle of conservation of thermal energy for application to one- and two-dimensional spaces. The basic concept in these models is to separate water temperature into two parts, (1) excess temperature due to thermal loading and (2) natural (ambient) temperature. This separation allows excess temperature to be calculated from the models without incoming radiation data. Natural temperature may either be measured in prototypes or calculated from the model. If use is made of the model, however, incoming radiation is required as input data. Comparison of observed and calculated temperatures in seven natural streams shows that the models are capable of predicting transient temperature regimes satisfactorily in most cases. (Woodard-USGS)

Jackman, Alan P.; Yotsukura, Nobuhiro

1977-01-01

333

Breastfeeding Following a Natural Disaster  

MedlinePLUS

... or visit us online at: www.OTISpregnancy.org . Breastfeeding Following a Natural Disaster The information below will ... advice from your health care provider. Why is breastfeeding good for my baby? There are many benefits ...

334

Natural Radionuclides in Ground Water.  

ERIC Educational Resources Information Center

Described are the natural trace radionuclides in ground water. Indicates the geologic origin of these radionuclides. Discusses the importance of these radionuclides. Suggests future uses of a number of additional radionuclides. (CW)

Davis, Stanley N.

1988-01-01

335

Natural gas hydrates storage project.  

National Technical Information Service (NTIS)

Since economical and environmental conditions could be positively affected by greater use of natural gas, especially for peak-loading events of power plants, the feasibility of overcoming a major impediment of safe, above-ground storage in heavily populat...

R. E. Rogers

1999-01-01

336

Nature of the Bioterrorism Threat.  

National Technical Information Service (NTIS)

This analysis provides an overview of the nature of the bioterrorism threat. It identifies potential CDC Class A biological agents that are likely candidates for use in a terrorist incident and describes the known sources of vulnerability. The paper also ...

J. L. Regens

2003-01-01

337

Natural Gas Monthly August 1998  

SciTech Connect

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information. Explanatory notes supplement the information found in tables of the report. A description of the data collection surveys that support the NGM is provided. A glossary of the terms used in this report is also provided to assist readers in understanding the data presented in this publication.

NONE

1998-08-01

338

Charles Darwin II: Natural selection  

NSDL National Science Digital Library

This is the second in a series of modules which detail the research of Charles Darwin and evolutionary theory. This module continues with a discussion of the processes that led to Darwin's formulation of the theory of natural selection.

Rosenberger, Alfred

2004-02-12

339

Is Science Biased Toward Natural?  

EPA Science Inventory

Having widely available, accurate, understandable, and unbiased scientific information is central to the successful resolution of the typically contentious, divisive, and litigious natural resource policy issue. Three examples are offered to illustrate how science is often misus...

340

Analyses of Natural Gases, 1971.  

National Technical Information Service (NTIS)

The publication contains routine analyses and related source data for 475 natural gas samples from 17 States and two foreign countries. Of this total, 454 samples were collected during calendar year 1971. The other 21 samples were collected during previou...

L. E. Cardwell L. F. Benton

1972-01-01

341

Analyses of Natural Gases, 1982.  

National Technical Information Service (NTIS)

This Bureau of Mines publication contains analyses and related source data for 271 natural gas samples from 22 States collected during calendar year 1982. All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences ...

R. D. Miller F. R. Hertweck

1983-01-01

342

Transportation of Liquefied Natural Gas.  

National Technical Information Service (NTIS)

The report presents a factual description of the liquefied natural gas (LNG) system and facilities, and the Federal regulatory process that governs their development and operations. Key portions of the LNG system that are vulnerable to technological or po...

1977-01-01

343

Methane emissions from natural wetlands  

Microsoft Academic Search

Methane is considered one of the most important greenhouse gases in the atmosphere. Because of the strict anaerobic conditions required by CH4-generating microorganisms, natural wetland ecosystems are one of the main sources of biogenic CH4. The total natural wetland area is estimated to be 5.3 to 5.7 × 1012 m2, making up less than 5% of the Earth's land surface.

Zhengping Wang; Dong Zeng; William H. Patrick

1996-01-01

344

Natural cement and monumental restoration  

Microsoft Academic Search

Natural cement, called “Roman” cement, was invented at the end of the 19th century and played an important role in the development\\u000a of civil engineering works until the 1860s. More surprisingly, it was also used to restore historic buildings, such as gothic\\u000a cathedrals. This paper deals with the mineralogy and the durability of natural cement in the particular case of

C. Gosselin; V. Verges-Belmin; A. Royer; G. Martinet

2009-01-01

345

Investigating Natural Selection: Elementary School  

NSDL National Science Digital Library

This lesson plan is designed for fourth and fifth grade students learning about natural selection. The class will investigate the predator-prey relationship as an example of how natural selection occurs in a population. Students will work in groups of three or four and observe how predators select their prey, and how this affects the subsequent populations of a species. The concept of camouflage is also covered in the material. This lesson is designed to take about sixty minutes of class time.

2010-01-01

346

Capillary electrophoresis of natural products.  

PubMed

Capillary electrophoresis (CE) and micellar electrokinetic chromatography were used for the separation of widely different compounds from natural materials including antibiotics, humic substances, flavonoids, isoflavonoids, illicit drugs, coumarins, alkaloids, steroids, Chinese herbal preparations, nicotine, caffeine, amphetamines, toxins such as aflatoxins B1, B2, G1, G2, mycotoxins, heptapeptide toxins and others, ephedrine compounds, mineral elements, and natural compounds in biological samples. A discussion of sample extraction and clean-up and the advantages of using CE is also presented. PMID:9456058

Issaq, H J

1997-11-01

347

EYE MOVEMENTS IN NATURAL ENVIRONMENTS  

Microsoft Academic Search

Abstract How do the limitations of attention and working memory,constrain acquisition of information in the context of natural behavior? Overt fixations carry much,information about current attentional state, and are a revealing indicator of this process. Fixation patterns in natural behavior are largely determined,by the momentary,task. The implication of this is that fixation patterns are a learnt behavior. We review several

ROGER P. G. VAN GOMPEL

2007-01-01

348

Mössbauer study of natural wolframites  

Microsoft Academic Search

The first Mössbauer results obtained with powdered samples of natural wolframites Fex Mn1-x WO4 from some famous Portuguese and Peruvian mines are reported here. The Mössbauer experiments have been carried out at 300, 77 and 4.2 K with four natural and one synthetic powdered samples of different compositions. The Mössbauer parameter values can be attributed to a high spin ferrous

R. Guillen; J. R. Regnard; J. Amossé

1982-01-01

349

TRP Modulation by Natural Compounds.  

PubMed

The use of medicinal plants or other naturally derived products to relieve illness can be traced back over several millennia, and these natural products are still extensively used nowadays. Studies on natural products have, over the years, enormously contributed to the development of therapeutic drugs used in modern medicine. By means of the use of these substances as selective agonists, antagonists, enzyme inhibitors or activators, it has been possible to understand the complex function of many relevant targets. For instance, in an attempt to understand how pepper species evoke hot and painful actions, the pungent and active constituent capsaicin (from Capsicum sp.) was isolated in 1846 and the receptor for the biological actions of capsaicin was cloned in 1997, which is now known as TRPV1 (transient receptor potential vanilloid 1). Thus, TRPV1 agonists and antagonists have currently been tested in order to find new drug classes to treat different disorders. Indeed, the transient receptor potential (TRP) proteins are targets for several natural compounds, and antagonists of TRPs have been synthesised based on the knowledge of naturally derived products. In this context, this chapter focuses on naturally derived compounds (from plants and animals) that are reported to be able to modulate TRP channels. To clarify and make the understanding of the modulatory effects of natural compounds on TRPs easier, this chapter is divided into groups according to TRP subfamilies: TRPV (TRP vanilloid), TRPA (TRP ankyrin), TRPM (TRP melastatin), TRPC (TRP canonical) and TRPP (TRP polycystin). A general overview on the naturally derived compounds that modulate TRPs is depicted in Table 1. PMID:24961985

Meotti, Flavia Carla; Lemos de Andrade, Edinéia; Calixto, João B

2014-01-01

350

US Vulnerability to Natural Disasters  

NASA Astrophysics Data System (ADS)

Natural disasters result from the coincidence of natural events with the built environment. Our nation's infrastructure is growing at an exponential rate in many areas of high risk, and the Federal government's liability is increasing proportionally. By superimposing population density with predicted ground motion from earthquakes, historical hurricane tracks, historical tornado locations, and areas within the flood plain, we are able to identify locations of high vulnerability within the United States. We present a comprehensive map of disaster risk for the United States that is being produced for the Senate Natural Hazards Caucus. The map allows for the geographic comparison of natural disaster risk with past disaster declarations, the expenditure of Federal dollars for disaster relief, population increase, and variations of GDP. Every state is vulnerable to natural disasters. Although their frequency varies considerably, the annualized losses for disaster relief from hurricanes, earthquakes, and floods are approximately equivalent. While fast-growing states such as California and Florida remain highly vulnerable, changes in the occurrence of natural events combined with population increases are making areas such as Texas, North Carolina, and the East Coast increasingly vulnerable.

van der Vink, G.; Apgar, S.; Batchelor, A.; Carter, C.; Gail, D.; Jarrett, A.; Levine, N.; Morgan, W.; Orlikowski, M.; Pray, T.; Raymar, M.; Siebert, A.; Shawa, T. W.; Wallace, C.

2002-05-01

351

Natural gas monthly, November 1997  

SciTech Connect

This issue of the Natural Gas Monthly presents the most recent estimates of natural gas data from the Energy Information Administration. Estimates extend through November for many data series, and through August for most natural gas prices. Highlights of the most recent data estimates are: (1) Preliminary estimates of dry natural gas production and total consumption available through November 1997 indicate that both series are on track to end the year at levels close to those of 1996. Cumulative dry production is one-half percent higher than in 1996 and consumption is one-half percent lower. (2) Natural gas production is estimated to be 52.6 billion cubic feet per day in November 1997, the highest rate since March 1997. (3) After falling 8 percent in July 1997, the national average wellhead price rose 10 percent in August 1997, reaching an estimated $2.21 per thousand cubic feet. (4) Milder weather in November 1997 compared to November 1996 has resulted in significantly lower levels of residential consumption of natural gas and net storage withdrawls than a year ago. The November 1997 estimates of residential consumption and net withdrawls are 9 and 20 percent lower, respectively, than in November 1996.

NONE

1997-11-01

352

Noninvasive monitoring of CO2 sequestration sites using airborne EM technology  

NASA Astrophysics Data System (ADS)

Usage of conventional airborne EM methods for studies related to CO2 sequestration reservoirs have been restricted up to date due to depth and system noise limitations. Recently a family of new EM systems was developed and launched in Canada, allowing superior depth of investigation to that of the conventional EM systems. Depending on the resistivity of the area such systems are capable of recording response from targets emplaced at the depths of up to 2 kilometers below surface. These systems are powered by natural (telluric and storm lightning) EM fields and are particularly sensitive to contrast in electrical properties of the subsurface, rather than absolute values of the conductivities, which make these systems suitable for usage in both resistive and conductive environments, including the subsurface identification and mapping of gas, hydrocarbons, liquid CO2 and supercritical CO2. Based on the well log data collected at one of the proposed sequestration sites, forward modeling has been carried out in order to study which changes in electrical properties of reservoir rocks before and after the introduction of CO2 to the sequestration reservoir are sufficient to provide enough contrast so they become detectable by EM systems. The results of the modeling showed that under favourable conditions it is possible to differentiate between brine-filled reservoirs versus CO2-filled reservoir at a depth of more than 1 kilometer with the main controlling parameters being reservoir effective porosity, thickness, Total Dissolved Solids (TDS) content of the pore-filling fluid and CO2 saturation after the injection. EM surveying can play a crucial role in studies of moderately deep-seated reservoirs, specifically can assist in monitoring CO2 injection and migration and can provide some additional data regarding the CO2 saturation level. The benefits of application of these new EM systems compared with 3D reflection seismic, VSP, gravity, and other geophysical methods will also be discussed.

Kaminski, V.; Harbert, W. P.; Legault, J. M.

2009-12-01

353

Removal of sulfur compounds from utility pipelined synthetic natural gas using modified activated carbons  

Microsoft Academic Search

Synthetic natural gas (SNG), which is produced from petroleum and distributed via pipeline in Honolulu by The Gas Company, was analyzed using a gas chromatograph equipped with a sulfur chemiluminescence detector (GC\\/SCD). Hydrogen sulfide (H2S), methyl mercaptan (MM), ethyl mercaptan (EM), dimethylsulfide (DMS), dimethyl disulfide (DMDS), tetrahydrothiophene (THT), ethyl disulfide (EDS), and one unidentified compound (UN1) were detected. Among these

Hong Cui; Scott Q. Turn; Mark A. Reese

2009-01-01

354

SuperNatural: a searchable database of available natural compounds  

PubMed Central

Although tremendous effort has been put into synthetic libraries, most drugs on the market are still natural compounds or derivatives thereof. There are encyclopaedias of natural compounds, but the availability of these compounds is often unclear and catalogues from numerous suppliers have to be checked. To overcome these problems we have compiled a database of ?50?000 natural compounds from different suppliers. To enable efficient identification of the desired compounds, we have implemented substructure searches with typical templates. Starting points for in silico screenings are about 2500 well-known and classified natural compounds from a compendium that we have added. Possible medical applications can be ascertained via automatic searches for similar drugs in a free conformational drug database containing WHO indications. Furthermore, we have computed about three million conformers, which are deployed to account for the flexibilities of the compounds when the 3D superposition algorithm that we have developed is used. The SuperNatural Database is publicly available at . Viewing requires the free Chime-plugin from MDL (Chime) or Java2 Runtime Environment (MView), which is also necessary for using Marvin application for chemical drawing.

Dunkel, Mathias; Fullbeck, Melanie; Neumann, Stefanie; Preissner, Robert

2006-01-01

355

SuperNatural: a searchable database of available natural compounds.  

PubMed

Although tremendous effort has been put into synthetic libraries, most drugs on the market are still natural compounds or derivatives thereof. There are encyclopaedias of natural compounds, but the availability of these compounds is often unclear and catalogues from numerous suppliers have to be checked. To overcome these problems we have compiled a database of approximately 50,000 natural compounds from different suppliers. To enable efficient identification of the desired compounds, we have implemented substructure searches with typical templates. Starting points for in silico screenings are about 2500 well-known and classified natural compounds from a compendium that we have added. Possible medical applications can be ascertained via automatic searches for similar drugs in a free conformational drug database containing WHO indications. Furthermore, we have computed about three million conformers, which are deployed to account for the flexibilities of the compounds when the 3D superposition algorithm that we have developed is used. The SuperNatural Database is publicly available at http://bioinformatics.charite.de/supernatural. Viewing requires the free Chime-plugin from MDL (Chime) or Java2 Runtime Environment (MView), which is also necessary for using Marvin application for chemical drawing. PMID:16381957

Dunkel, Mathias; Fullbeck, Melanie; Neumann, Stefanie; Preissner, Robert

2006-01-01

356

DOE/EM Criticality Safety Needs Assessment  

SciTech Connect

The issue of nuclear criticality safety (NCS) in Department of Energy Environmental Management (DOE/EM) fissionable material operations presents challenges because of the large quantities of material present in the facilities and equipment that are committed to storage and/or material conditioning and dispositioning processes. Given the uncertainty associated with the material and conditions for many DOE/EM fissionable material operations, ensuring safety while maintaining operational efficiency requires the application of the most-effective criticality safety practices. In turn, more-efficient implementation of these practices can be achieved if the best NCS technologies are utilized. In 2002, DOE/EM-1 commissioned a survey of criticality safety technical needs at the major EM sites. These needs were documented in the report Analysis of Nuclear Criticality Safety Technology Supporting the Environmental Management Program, issued May 2002. Subsequent to this study, EM safety management personnel made a commitment to applying the best and latest criticality safety technology, as described by the DOE Nuclear Criticality Safety Program (NCSP). Over the past 7 years, this commitment has enabled the transfer of several new technologies to EM operations. In 2008, it was decided to broaden the basis of the EM NCS needs assessment to include not only current needs for technologies but also NCS operational areas with potential for improvements in controls, analysis, and regulations. A series of NCS workshops has been conducted over the past years, and needs have been identified and addressed by EM staff and contractor personnel. These workshops were organized and conducted by the EM Criticality Safety Program Manager with administrative and technical support by staff at Oak Ridge National Laboratory (ORNL). This report records the progress made in identifying the needs, determining the approaches for addressing these needs, and assimilating new NCS technologies into EM fissionable material operations. In addition, the report includes projections of future EM needs and associted recommendations.

Westfall, Robert Michael [ORNL; Hopper, Calvin Mitchell [ORNL

2011-02-01

357

Natural Selection Promotes Antigenic Evolvability  

PubMed Central

The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed ‘cassettes’ that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios) and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish chronic infections.

Graves, Christopher J.; Ros, Vera I. D.; Stevenson, Brian; Sniegowski, Paul D.; Brisson, Dustin

2013-01-01

358

Desenvolvimento do processo de deposicao eletroforetica de boro em substratos de aluminio, destinados a construcao de detectores de neutrons. (Development of the process of boron electrophoresis deposition on aluminum substate to be used in the construction of neutron detectors).  

National Technical Information Service (NTIS)

Process of baron electrophoresis depositon on large areas of aluminum substrates was developed with the aim of using them in the construction of neutron detectors. After definition and optimization of the boron electrophoresis parameters, depositions of (...

M. H. Oliveira Sampa L. A. Vinhas

1989-01-01

359

Efeito de antagonistas histaminergicos sobre o desenvolvimento de edema pulmonar em camundongos infectados com P-berghei. (Effect of a histaminergic antagonist over the pulmonary edema in P. berghei infected mice).  

National Technical Information Service (NTIS)

The involvement of histaminergic mechanisms in the pathogenesis of pulmonary oedema observed in p. berghei - infected mice was investigated. Histamine concentrations in plasma and whole blood of infected and normal mice were determined by radioenzymatic a...

M. A. Martins

1985-01-01

360

Natural pigments and sacred art  

NASA Astrophysics Data System (ADS)

Since the dawn of mankind, cavemen has expressed himself through art. The earliest known cave paintings date to some 32,000 years ago and used 4 colours derived from the earth. These pigments were iron oxides and known as ochres, blacks and whites. All pigments known by the Egyptians, the Greeks, the Romans and Renaissance man were natural and it was not until the 18th century that synthetic pigments were made and widely used. Until that time all art, be it sacred or secular used only natural pigments, of which the preparation of many have been lost or rarely used because of their tedious preparation. As a geologist, a mineralogist and an artist specializing in iconography, I have been able to rediscover 89 natural pigments extracted from minerals. I use these pigments to paint my icons in the traditional Byzantine manner and also to restore old icons, bringing back their glamour and conserving them for years to come. The use of the natural pigments in its proper way also helps to preserve the traditional skills of the iconographer. In the ancient past, pigments were extremely precious. Many took an exceedingly long journey to reach the artists, and came from remote countries. Research into these pigments is the work of history, geography and anthropology. It is an interesting journey in itself to discover that the blue aquamarines came from Afghanistan, the reds from Spain, the greens Africa, and so on. In this contribution I will be describing the origins, preparation and use of some natural pigments, together with their history and provenance. Additionally, I will show how the natural pigments are used in the creation of an icon. Being a geologist iconographer, for me, is a sacrement that transforms that which is earthly, material and natural into a thing of beauty that is sacred. As bread and wine in the Eucharist, water during baptism and oil in Holy Union transmit sanctification to the beholder, natural pigments do the same when one considers an icon. The iconographer uses earthly creations to create divine images: "Thine own of Thine own we offer unto Thee." (Byzantine Liturgy). Thus, by combining geology with art and religion, I can render homage to God through His creation by using minerals of the Planet Earth, as natural pigments in painting His image.

Kelekian, Lena, ,, Lady

2010-05-01

361

Environmentalism and natural aggregate mining  

USGS Publications Warehouse

Sustaining a developed economy and expanding a developing one require the use of large volumes of natural aggregate. Almost all human activity (commercial, recreational, or leisure) is transacted in or on facilities constructed from natural aggregate. In our urban and suburban worlds, we are almost totally dependent on supplies of water collected behind dams and transported through aqueducts made from concrete. Natural aggregate is essential to the facilities that produce energy-hydroelectric dams and coal-fired powerplants. Ironically, the utility created for mankind by the use of natural aggregate is rarely compared favorably with the environmental impacts of mining it. Instead, the empty quarries and pits are seen as large negative environmental consequences. At the root of this disassociation is the philosophy of environmentalism, which flavors our perceptions of the excavation, processing, and distribution of natural aggregate. The two end-member ideas in this philosophy are ecocentrism and anthropocentrism. Ecocentrism takes the position that the natural world is a organism whose arteries are the rivers-their flow must not be altered. The soil is another vital organ and must not be covered with concrete and asphalt. The motto of the ecocentrist is "man must live more lightly on the land." The anthropocentrist wants clean water and air and an uncluttered landscape for human use. Mining is allowed and even encouraged, but dust and noise from quarry and pit operations must be minimized. The large volume of truck traffic is viewed as a real menace to human life and should be regulated and isolated. The environmental problems that the producers of natural aggregate (crushed stone and sand and gravel) face today are mostly difficult social and political concerns associated with the large holes dug in the ground and the large volume of heavy truck traffic associated with quarry and pit operations. These concerns have increased in recent years as society's demand for living space has encroached on the sites of production; in other words, the act of production has engendered condemnation. Many other environmental problems that are associated with dust and noise and blasting from quarry and pit operations have been reduced through the efficient use of technology. Recycling concrete in buildings, bridges, and roads and asphaltic pavements will ultimately reduce the demand for virgin natural aggregate. The impact created by the large holes in the ground required for the mining of natural aggregate can be greatly reduced by planning their reclamation before mining begins. ?? 2002 International Association for Mathematical Geology.

Drew, L. J.; Langer, W. H.; Sachs, J. S.

2002-01-01

362

What is Imbalance of Nature?  

NASA Astrophysics Data System (ADS)

The Mother Nature is imbalanced at all. The Mother Nature is every moment new, never returns to previous condition. The gravity and magnetosphere are changeable and imbalanced. The Sun is changeable and imbalanced. The climate is changeable and imbalanced. The atmosphere is changeable and imbalanced. The ocean is changeable and imbalanced. The crust and deep interior are changeable and imbalanced. The cryosphere is changeable and imbalanced. The life is simultaneously as the creator and the result of the imbalance of Nature. The people society is changeable and imbalanced. All chemical, physical, social, and other phenomenons are changeable and imbalanced. It's just that each phenomenon of the Mother Nature has some personal time-scale: one change in a nanosecond, and looks like for us as instable, i.e. imbalanced; while others change over millions years and, therefore, to us looks like not changeable, i.e. balanced. The scientists who are studying the Nature have convinced that the real balance never exist in Nature. Sometimes we can see something that is stable, i.e. balanced. But on closer study it appears that we are witnessing is not eternal rest and balance, it is not eternal STOP, but it is the perpetual motion, changing, there are a lot of imbalances. The balance it can be some result of the temporary mutual compensation the imbalanced processes in opposite directions. The balance it can be also some result of the inaccurate measurement, misunderstanding of conception or even request from bosses. But if we start use more accurate measurements, improve the models and not fear the bosses, than usually we got some new details. These new details show thet under the balanced visibility in really is hiding the interaction of many imbalanced processes of different directions. The balanced logic usually answers to question: What is it? The balanced answers are approximate and it will be updated many times during the development of science and practice. The imbalanced logic usually answers to question: How and why it is happened in details? The imbalanced answers are approximate also, and they will also be updated many times during the development of science and practice. But the imbalanced logic allows us to overcome of the inertia of the balanced logic and much closer come up to understanding the essence of Nature. We try to answer the central question of humanity: How to get calm, i.e. balanced life if the everything around us is imbalanced, the people themselves are restless and not eternal? The study of the Imbalance of Nature is multi-disciplinary because Nature is one. It is our main advantage.

Kontar, V. A.

2012-12-01

363

Natural pedagogy as evolutionary adaptation  

PubMed Central

We propose that the cognitive mechanisms that enable the transmission of cultural knowledge by communication between individuals constitute a system of ‘natural pedagogy’ in humans, and represent an evolutionary adaptation along the hominin lineage. We discuss three kinds of arguments that support this hypothesis. First, natural pedagogy is likely to be human-specific: while social learning and communication are both widespread in non-human animals, we know of no example of social learning by communication in any other species apart from humans. Second, natural pedagogy is universal: despite the huge variability in child-rearing practices, all human cultures rely on communication to transmit to novices a variety of different types of cultural knowledge, including information about artefact kinds, conventional behaviours, arbitrary referential symbols, cognitively opaque skills and know-how embedded in means-end actions. Third, the data available on early hominin technological culture are more compatible with the assumption that natural pedagogy was an independently selected adaptive cognitive system than considering it as a by-product of some other human-specific adaptation, such as language. By providing a qualitatively new type of social learning mechanism, natural pedagogy is not only the product but also one of the sources of the rich cultural heritage of our species.

Csibra, Gergely; Gergely, Gyorgy

2011-01-01

364

Toward a New Natural Medicine  

NASA Astrophysics Data System (ADS)

Treatments summarized under the term "natural medicine," i.e., those offered as an alternative or in addition to conventional medicine, have enjoyed a surge in popularity in recent years. The "natural" descriptor employed in connection with these healing methods is frequently misunderstood, leading to underestimation of the risks arising from incorrect use. However, the essential principle underlying traditional natural medicine, mobilization of the body's own forces against disease, is increasingly being employed in a new, rational form of medicine: molecular medicine. A range of natural endogenous substances for medical use are already available. Human proteins such as erythropoietin can now be produced as medicines in highly pure form with the aid of genetic engineering techniques. Our increasing understanding of the function of our genes and the resulting descriptions of molecular mechanisms underlying disease are also helping us to utilize the body's own construction set. New techniques such as gene therapy will in future enable us to reproduce the natural conditions in the healthy body with increasing specificity in our attempts to cure illnesses. One such application will be the activation of the immune system to combat cancer. The complete decoding of the human genome will not only allow illnesses to be described, and possibly prevented, at an earlier stage. Illnesses will also be able to described more precisely and individually at the molecular level, opening up the possibility of targeted, patient-specific cures.

Buckel, Peter

365

Natural patterns of energy dispersal.  

PubMed

Universal patterns such as power-law dependences, skewed distributions, tree-like structures, networks and spirals are associated with energy dispersal processes using the principle of least action. Also ubiquitous temporal courses such as sigmoid growth, bifurcations and chaos are ascribed to the decrease of free energy in the least time. Moreover, emergence of natural standards such as the common genetic code and chirality consensus of amino acids are understood to follow from the quest to maximize the dispersal of energy. Many mathematical functions that model natural patterns and processes are found as approximations of the evolutionary equation of motion that has been derived from statistical physics of open systems. The evolutionary processes can be described as flows of energy that run from high energy sources to low energy sinks in the least time. However, the equation of evolution cannot be solved in general because the flows of energy and their driving forces are inseparable. Since the energy of the system keeps changing, the paths of evolution cannot be integrated from a given initial state to a final state. Although evolutionary courses of these non-Hamiltonian systems with two or more alternative ways of dissipation cannot be predicted, the flows of energy will search and naturally select paths of least action, known as geodesics, to consume free energy in the least time. The scale-invariant natural patterns follow from this natural law that impinges on processes at all scales of space and time. PMID:21030325

Mäkelä, Teemu; Annila, Arto

2010-12-01

366

School Budget Hold'em Facilitator's Guide  

ERIC Educational Resources Information Center

"School Budget Hold'em" is a game designed to help school districts rethink their budgeting process. It evolved out of Education Resource Strategies' (ERS) experience working with large urban districts around the country. "School Budget Hold'em" offers a completely new approach--one that can turn the budgeting process into a long-term visioning…

Education Resource Strategies, 2012

2012-01-01

367

Risco no mercado de arroz em casca  

Microsoft Academic Search

O presente trabalho avaliou as características das séries de retornos, normalmente encontradas em séries financeiras, para dados do mercado de arroz em casca ao produtor do Rio Grande do Sul. Um modelo da classe GARCH (1,1) tipo VaR foi utilizado para obter previsões da variância condicional e verificar o risco incorrido pelas posições comprada e vendida no mercado de arroz

Andreia Cristina de Oliveira Adami; Geraldo SantAna de Camargo Barros

2008-01-01

368

Theory and detection scheme of seismic EM signals transferred into the atmosphere from the oceanic and continental lithosphere  

NASA Astrophysics Data System (ADS)

Due to the compound structure of the medium and large portions of energy transferred, a seismic excitation in the oceanic or continental lithosphere disturbs all types of geophysical fields. To investigate the problem of electromagnetic (EM) disturbances in the atmosphere from the seismically activated lithosphere, we have formulated two mathematical models of interaction of fields of different physical nature resulting in arising of the low-frequency (from 0.1 to 10 Hz by amplitude of a few hundreds of pT) EM signals in the atmosphere. First we have considered the EM field generation in the moving oceanic lithosphere and then in the moving continental one. For both cases, the main physical principles and geological data were applied for formulation of the model and characteristics of the computed signals of different nature agree with measurements of other authors. On the basis of the 2D model of the seismo-hydro-EM-temperature interaction in the lithosphere-Ocean-atmosphere domain, a block-scheme of a multisensory vertically distributed (from a seafloor up to the ionosphere) tsunami precursors' detection system is described. On the basis of the 3D model of the seismo-EM interaction in a lithosphere-atmosphere domain, we explain why Prof. Kopytenko (Inst. IZMIRAN of Russian Acad. Sci.) and co-authors were able to estimate location of the future seismic epicenter area from their magnetic field measurements in the atmosphere near the earth's surface.

Novik, Oleg; Ershov, Sergey; Ruzhin, Yuri; Smirnov, Fedor; Volgin, Maxim

2014-07-01

369

Natural transformation in river epilithon.  

PubMed Central

Natural transformation was demonstrated in unenclosed experiments incubated in river epilithon. Strains of Acinetobacter calcoaceticus were transformed to prototrophy by either free DNA (lysates) or live donor cells. The sources of transforming DNA and recipient culture were immobilized on filters, secured to stones, and incubated midstream in the river. The transfer frequency generally increased with temperature. No transfer was detected in the river Taff below 10 degrees C. The age of the recipient culture affected the transformation frequencies in situ but did not significantly affect the transfer frequency on laboratory media. Transformation of recipient cultures which had been incorporated into the natural epilithic biofilm and transformation of the plasmid pQM17 in situ were also demonstrated. This study provides the first direct evidence of natural transformation in situ of bacteria incorporated into an indigenous community.

Williams, H G; Day, M J; Fry, J C; Stewart, G J

1996-01-01

370

Natural GUT and the cosmology  

SciTech Connect

In the natural GUT, not only realistic quark and lepton mass matrices can be obtained but also the most serious problem in the SUSY GUT, which is called the doublet-triplet splitting problem, can be solved under the natural assumption that all the interactions which are allowed by the symmetry are introduced with O(1) coefficients (including the higher dimensional operators). In this manuscript, we examine several cosmological aspects which are related with the natural GUT, B - L-genesis, non-thermal production of dark matter (DM), vacuum selection by particle production, and the inflation after the trapping. These works are based on several papers[1, 2, 3] collaborated with S. Enomoto, S. Iida, Y. Kurata, and T. Matsuda.

Maekawa, Nobuhiro [Nagoya Univ. Kobayashi-Maskawa Institute, Nagoya 464-8602 and Nagoya Univ. Department of Physics, Nagoya 464-8602 (Japan)

2012-07-27

371

Deaths involving natural gas inhalation.  

PubMed

Death due to gas inhalation is accidental or suicidal. Natural gas can be a cause of death as a result of oxygen replacement in the atmosphere. Three male victims who were killed from gas inhalation are described in this study. One 19-year-old man attempted suicide using a combination of plastic bag suffocation and natural gas tube in his mouth. The other victim (24 years old man) attempted suicide by natural gas inhalation, and the cause of death of the third victim was inhalation of the vapor from a furnace that contained crude oil or gasoline. Methanol was detected in blood and liver samples by headspace gas chromatography (HSGC) and headspace gas chromatography-mass spectrometry (HSGCMS). Carboxyhemoglobin (CO-Hb) and other drugs and poisons were not detected in blood and liver samples. PMID:20430818

Maryam, Akhgari; Elham, Bazmi

2010-07-01

372

Synthesis of Polycyclic Natural Products  

SciTech Connect

With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is imperative for the expansion of this highly interdisciplinary field of science. In addition to the practical applications of total syntheses, the structural complexity of natural products represents a worthwhile challenge in itself. The pursuit of concise and efficient syntheses of complex molecules is both gratifying and enjoyable.

Tuan Hoang Nguyen

2003-05-31

373

SRI International: Natural Language Program  

NSDL National Science Digital Library

This website describes the Natural Language Program that is part of SRI International's Artificial Intelligence Center. The center's research focuses on natural language theory and applications, with emphasis on three subgroups of study. The subprogram on Multimedia / Multimodal Interfaces seeks to understand the optimal ways in which natural language can be incorporated into multimedia interfaces. The subprogram on Spoken Language Systems integrates linguistic processing with speech recognition for use in ATIS, a system for retrieving airline schedules, fares, and related information from a relational database. The subprogram on Written Language Systems researches the problems involved in interpreting and extracting information from written text, such as on-line newspaper articles. Additional information on these projects, related publications, and software are available from this website.

374

Natural gas monthly, February 1997  

SciTech Connect

This issue of the Natural Gas Monthly presents estimates of natural gas supply and consumption through February 1997. Estimates of natural gas prices are through November 1996 except electric utility prices that are through October 1996. Cumulatively for January through February 1997, the daily average rates for several data series remain close to those of 1996. (Comparing daily rates accounts for the fact that February 1996 had 29 days.) Daily total consumption for January through February is estimated to be 83 billion cubic feet per day, 1 percent higher than during the same period in 1996. Similarly, the estimate of average daily production of 53 billion cubic feet is 1.5 percent higher than in 1996, while daily net imports during the first 2 months of 1997 are virtually unchanged from 1996.

NONE

1997-02-01

375

Regional Trading Arrangement: Natural or SuperNatural?  

Microsoft Academic Search

This paper summarizes recent research by the authors on the effects of free trade areas (FTAs). Within our model, which emphasizes inter-continental transport costs, several conclusions arise. (1) FTAs are likely to be detrimental over a moderate range of parameter values, even if drawn along natural regional lines. (2) A small margin of preferences for neighbors is beneficial. (3) Optimal

Jeffrey A. Frankel; Ernesto Stein; Shang-Jin Wei

1996-01-01

376

New Trends in Natural Language Processing. Statistical Natural Language Processing.  

National Technical Information Service (NTIS)

The field of natural language processing (NLP) has seen a dramatic shift in both research direction and methodology in the past several years. In the past, most work in computational linguistics tended to focus on purely symbolic methods. Recently, more a...

M. Marcus

1994-01-01

377

Naturally Speaking: A Systems Biology Tool With Natural Language Interfaces.  

National Technical Information Service (NTIS)

This short paper describes a systems biology software tool that can engage in a dialogue with a biologist by responding to questions posed to it in English (or another natural language) regarding the behavior of a complex biological system, and by suggest...

M. Antoniotti I. T. Lau B. Mishra

2004-01-01

378

On Adventure Therapy and the Natural Worlds: Respecting Nature's Healing.  

ERIC Educational Resources Information Center

The anthropomorphic paradigm in psychology and psychotherapy has prevented nature from being considered a factor in the curative relationship in adventure therapy. The effectiveness of therapeutic interventions are credited instead to human factors such as program design and facilitation. A paradigm shift is needed in adventure therapy to accept…

Beringer, Almut; Martin, Peter

2003-01-01

379

Joint Natural Resources and Government Policy: Helium and Natural Gas  

Microsoft Academic Search

A model of jointly extracted natural resources is developed to analyze the effects of taxation policies. Under the assumptions of perfectly competitive resource owners and perfect foresight, the intertemporal equilibrium is described and contrasted with the single resource case. The effects of several subsidies on the equilibrium prices, and the extraction and consumption paths of the two resources, are analyzed

A. M. Hughey

1991-01-01

380

Introduction to the Nature Journal  

NSDL National Science Digital Library

This Smithsonian in Your Classroom is the third in a three-part series that brings together writing and other disciplines. In the lessons here, students exercise the observation skills that are essential to writing, visual art, and science. First, they try to use evocative language in describing pictures of birds from the SmithsonianâÂÂs National Zoo. They go on to record observations and to make hypotheses as they follow the behavior of animals on the National ZooâÂÂs live webcams. They can watch the giant pandas, the tigers, the cheetahs, the gorillas, or any of a dozen other species.These classroom activities are intended as a preface or complement to a project increasingly popular in elementary and middle schoolsâÂÂthe keeping of nature journals, whether on class outings or when the students are on their own. Included in the issue are words of advice for students from journal-keeping Smithsonian naturalists.The term nature journal seems to resist definition until we realize that the broadest definitions all apply. In Keeping a Nature Journal, the most popular recent book on the subject, Clare Walker Leslie puts it simply: âÂÂwhereas a diary or personal journal records your feelings toward yourself and others, a nature journal primarily records your responses to and reflections about the world of nature around you.âÂÂWith a subject as great as all outdoors, nature journals lend themselves to a wide range of expression. Sketches are often the most immediate way to capture the way things look. Deeper, written observations can be the basis for all kinds of creative writing.

2010-12-17

381

31 CFR 540.309 - Natural uranium.  

Code of Federal Regulations, 2013 CFR

...ASSETS CONTROL REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in nature, with an average concentration of 0.711 percent by weight of the isotope...

2013-07-01

382

34 CFR 303.18 - Natural environments.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Natural environments. 303.18 Section 303.18 Education...Other General Provisions § 303.18 Natural environments. As used in this part, natural environments means settings that are...

2009-07-01

383

34 CFR 303.18 - Natural environments.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Natural environments. 303.18 Section 303.18 Education...Other General Provisions § 303.18 Natural environments. As used in this part, natural environments means settings that are...

2010-07-01

384

Natural Gas Hydrates Update 1998-2000  

EIA Publications

Significant events have transpired on the natural gas hydrate research and development front since "Future Supply Potential of Natural Gas Hydrates" appeared in Natural Gas 1998 Issues and Trends and in the Potential Gas Committee's 1998 biennial report.

David F. Morehouse

2001-04-25

385

7 CFR 650.23 - Natural areas.  

Code of Federal Regulations, 2010 CFR

...enterprises. (3) Natural areas are established... (i) Furthering science and education. Natural areas provide sites...designate a TSC plant sciences discipline leader to...and assistance on natural areas to NRCS...

2009-01-01

386

The Anthropocene, Ethics, and the Nature of Nature  

NASA Astrophysics Data System (ADS)

For Earth scientists the Anthropocene has a strict meaning, tied to evidence that human activities have produced pervasive impacts on the Earth. But it is also significant for scholars outside the Earth sciences. Social scientists study the ways human societies transform the landscape to make it more suited to human habitation; the Anthropocene idea has already served to reveal conceptual linkages among physical and social science research programs. And the Anthropocene has important implications for normative theorists who enquire into the basis of ethical standards that, ideally, guide human activities within the environment. An influential view has held the condition of the Earth's systems in the absence of human interference as such a standard. This view emphasizes the preservation of environmental systems in (or restoration to) their "natural" condition—either because that condition is the most advantageous for human beings, or because those systems have an intrinsic moral value human beings ought to respect. However, Anthropocene research destabilizes the concept of nature. For the "natural" is typically opposed to the artificial, i.e. to the results of human action, and although nature obviously provides the context for human activity, that context is taken to be exogenously given. For virtually all of Earth's history, its systems were "natural" in this sense. However, since the appearance of life on Earth, organisms engaging in what is called niche construction have fundamentally transformed those systems up to the planetary scale. There is no reason to regard human niche construction (e.g. agriculture) as different in kind—though of course anthropogenic impacts are greater than the impacts of other species. It follows that the Anthropocene demands that we move away from an outlook based on a strict opposition between a "natural" condition and the human activities which change it, towards one that conceives of the natural not as a condition, but as a highly complex system of processes which includes human activity as a component. This outlook thus discounts the idea that there is a condition of the environment that, in virtue of being "natural," can meaningfully serve as an ethical standard for human activity. It might be feared that this outlook could weaken inhibitions that serve to lessen the impact human beings have on their surroundings. For in the absence of a natural standard, people might feel licensed to intensify their transformative activities, generating a feedback loop by which the emergence of the idea of the Anthropocene makes the appearance of widespread anthropogenic impacts on Earth more likely. However, it is not inevitable that the Anthropocene idea will prompt a runaway feedback process. For the idea by no means implies an absence of normative restraints on human behavior. Instead, in denying that there is a way nature "ought" to be, the Anthropocene lends support to ethical views that regard normative standards as human conventions, aimed at enhancing the interests of the human community. And because it is tied to a systemic view of human activity in the environment, the Anthropocene idea can help focus attention on ways certain activities lead to adverse impacts on human interests, thus providing an ethical justification for restraints on those activities. That is, the idea might help make anthropogenic change, not less likely, but more acceptable.

Trachtenberg, Z.

2012-12-01

387

North American Natural Gas Markets  

SciTech Connect

This report summarizes die research by an Energy Modeling Forum working group on the evolution of the North American natural gas markets between now and 2010. The group's findings are based partly on the results of a set of economic models of the natural gas industry that were run for four scenarios representing significantly different conditions: two oil price scenarios (upper and lower), a smaller total US resource base (low US resource case), and increased potential gas demand for electric generation (high US demand case). Several issues, such as the direction of regulatory policy and the size of the gas resource base, were analyzed separately without the use of models.

Not Available

1989-02-01

388

Teaching about natural background radiation  

NASA Astrophysics Data System (ADS)

Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also demonstrated to emphasize the important role of shielding in radiation protection. The measurements were carried out with a Geiger-Muller (GM)-based dosimeter and a NaI scintillation gamma-ray spectrometer, which are normally available in physics laboratories. Radioactivity in household materials was demonstrated using a gas mantle as an example.

Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

2013-07-01

389

Natural gas: Removing the obstacles  

SciTech Connect

Defining and then figuring out how to remove whatever obstacles may be blocking the wider use of natural gas was the purpose of a conference held early last month in Phoenix, Arizona. The unique, three-day event was jointly sponsored by the U.S. Department of Energy (DOE) and the National Association of Regulatory Utility Commissioners (NARUC). It drew an overflow crowd of more than 500, with a registration list that read like a Who's Who of the natural gas industry. This article summarizes some of the main points of this conference.

Romo, C.

1992-03-15

390

Hawaiian Natural Resources Monitoring Database  

NSDL National Science Digital Library

The University of Hawaii's Hawaiian Natural Resources Monitoring Database is a centralized database that includes monitoring data for Hawaii's natural resources. Designed to help meet the information needs of land managers in Hawaii, the database includes "standardized and fully-documented data collection efforts by federal, state, and private agencies." A license (free, with permission) is required to access the database. Recently, the site added an updated master species list for Hawaii and an update (from US Fish and Wildlife Service) on the Endangered/Threatened status of Hawaiian species (.zip format).

391

MyNaturePhotos.com  

NSDL National Science Digital Library

Nature lovers and photographers are invited to upload and share their favorite wildlife photos in this straightforward, privately hosted Web site, a place where "viewers from around the world can see what animals, plants, and landscapes look like in other places." MyNaturePhotos.com currently features a modest collection of images grouped by class (all vertebrate): birds, fish, mammals, and reptiles. Future versions of this Web site will be organized by taxonomy and by geographic location, with plans to map out territories and migration routes of each species. This could be an interesting site to watch as contributions from visitors start to increase.

2003-01-01

392

Nature: Web Specials: Sheep Cloning  

NSDL National Science Digital Library

_Nature_, the "international weekly journal of science," has created a web page to accompany the ground-breaking letter it published in the February 27, 1997 issue: "Viable offspring derived from fetal and adult mammalian cells," by I. Wilmut, et al. The letter is available, as well as a Nature Opinion piece, and short articles of commentary by Axel Kahn of the INSERM Laboratory of Research on Genetics and Molecular Pathology at the Cochin Institute of Molecular Genetics, Paris, and Colin Stewart of the NCI-Frederick Cancer Research and Development Center, Frederick, Maryland. Note that the site is free, but registration is required.

1997-01-01

393

Enantiomeric Natural Products: Occurrence and Biogenesis**  

PubMed Central

In Nature, chiral natural products are usually produced in optically pure form; however, on occasion Nature is known to produce enantiomerically opposite metabolites. These enantiomeric natural products can arise in Nature from a single species, or from different genera and/or species. Extensive research has been carried out over the years in an attempt to understand the biogenesis of naturally occurring enantiomers, however, many fascinating puzzles and stereochemical anomalies still remain.

Finefield, Jennifer M.; Sherman, David H.; Kreitman, Martin; Williams, Robert M.

2012-01-01

394

Automatically assigning medical codes using natural language processing  

US Patent & Trademark Office Database

A programmed implementation for automatically assigning medical codes (including diagnosis, procedure, and level of service--i.e., evaluation and management (EM)--codes) to computer readable physician notes using natural language processing. A system allows hospitals, physician management groups, and medical billing companies to automatically determine and assign the medical codes that are the basis of reimbursement for medical services. The proposed implementation can be in place of human medical coders who otherwise would be employed to determine and assign these codes. Implementation requires only minor modifications to the traditional data-flow and allows for major improvements in throughput and timeliness of billing. Further, the present scheme enables the collection of other demographic and clinical information that resides in physician notes, but that are currently too expensive and time consuming to extract by means of a human workforce.

2005-07-05

395

18 CFR 2.78 - Utilization and conservation of natural resources-natural gas.  

Code of Federal Regulations, 2010 CFR

...conservation of natural resources-natural gas. 2.78 Section 2.78 ...Policy and Interpretations Under the Natural Gas Act § 2.78 Utilization and conservation of natural resourcesânatural gas. (a)(1) The national...

2010-04-01

396

18 CFR 2.78 - Utilization and conservation of natural resources-natural gas.  

Code of Federal Regulations, 2010 CFR

...conservation of natural resources-natural gas. 2.78 Section 2.78 ...Policy and Interpretations Under the Natural Gas Act § 2.78 Utilization and conservation of natural resourcesânatural gas. (a)(1) The national...

2009-04-01

397

Natural Acceleration: Supporting Creative Trajectories  

ERIC Educational Resources Information Center

"Natural acceleration" happens through an internal fire that burns to learn and may transcend school boundaries. Based on their passionate interests and connections with a domain, children who hunger for domain understandings outside school curricula require different types of acceleration, motivated by these interests. The lifeworks, domains, and…

Cohen, LeoNora M.

2011-01-01

398

Dimensional stability of natural fibers  

NASA Astrophysics Data System (ADS)

One of the main problems associated with the use of natural fibers as reinforcing agents in composites is their uptake of moisture. Many natural fibers are lignocellulosic, which causes them to swell and shrink as the amount of available moisture changes. Swelling and shrinking can cause composites to prematurely fail. This paper presents the results of a preliminary study that considers the use of two different low molecular weight monomers, hydroxyethyl methacrylate (HEMA) and hydroxyethyl acrylate (HEA), polymerized by electron beam ionizing radiation, to dimensionally stabilize natural fibers. Eight different treatments consisting of varying amounts of monomer, encapsulating agent, and cross-linkers, were evaluated for their ability to dimensionally stabilize sisal fiber. Results indicate that both polymerized HEA and HEMA can reduce the swelling of sisal fiber. The effectiveness of HEA and HEMA can be further enhanced with the use of a cross-linker (SR 454). The use of hydroxylated monomers to dimensionally stabilize natural fibers may play an important role in reducing delamination and improving fiber-resin adhesion in composites.

Driscoll, Mark S.; Smith, Jennifer L.; Woods, Sean; Tiss, Kenneth J.; Larsen, L. Scott

2013-04-01

399

The physical nature of life  

Microsoft Academic Search

Life evolved from the primeval world of physics. Sensory systems inform animals of the natural environment, enabling them to conduct responsively. The discovery of weak, DC bioelectric fields in the vicinity of aquatic organisms and the role they play in guiding sharks and rays to their prey have led to the recognition of fundamental, hitherto less well known, physical aspects

Ad. J. Kalmijn; Ivan Fernando Gonzalez; Michael C. McClune

2002-01-01

400

Occupational Analysis: Natural Resources Technician  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) has provided this document which includes an overview of general required competencies for natural resources technicians. Suggested general areas of competence and specific tasks within each area are provided. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

2011-03-04

401

The Nature of Science Education  

ERIC Educational Resources Information Center

A number of studies have shown that spending time in nature produces cognitive benefits. What if a child's exposure to the out-of-doors is considered not just a beneficial extracurricular activity, but a fundamental building block to an elementary education in math and science? The Young Achievers Science and Math Pilot School operates a 9:30 a.m.…

Connors, Margaret M.; Perkins, Bill

2009-01-01

402

Adaptive management of natural resources  

Microsoft Academic Search

The concept of adaptive management has been embraced by natural resource managers worldwide, and in Australia the promise to manage adaptively underpins most government water related programs and projects. Adaptive management is learning from doing; learning comes through the implementation of policies and strategies, so adaptive management complements research-based learning. Passive adaptive management learns from the implementation of an historically

Catherine Allan

403

Heterotopic pregnancy in natural conception  

PubMed Central

Heterotopic gestation, although common with assisted reproductive techniques, is very rare in natural conception. A high index of suspicion can help in timely diagnosis and appropriate intervention. We report a case of heterotopic pregnancy in a 22-year-old woman presented with hemoperitoneum from ruptured tubal pregnancy with live intrauterine gestation at 10 weeks of amenorrhea, diagnosed on ultrasound examination.

MJ, Govindarajan; R, Rajan

2008-01-01

404

Using Natural Approach Teaching Techniques.  

ERIC Educational Resources Information Center

Describes a beginning foreign language class applying the principles of Stephen Krashen's "Natural Approach" and James Asher's "Total Physical Response" method. Initially students carry out the instructor's commands in the form of actions rather than being required to speak. In later stages role play and simple discussions are introduced. (LMO)

Whitman, Charles

1986-01-01

405

First Follow Nature, Kit II.  

ERIC Educational Resources Information Center

Developing pupils' awareness of their environment, learning to distinguish between what is pleasant and unpleasant, and examining acts of man to determine which are destructive and which are in harmony with nature are the purposes of Scholastic's Earth Corps Environmental Study Kits for Grades 1-6. This kit explores in depth the reasons some…

1971

406

Research in Natural Language Understanding.  

National Technical Information Service (NTIS)

This report contains an annual summary of BBN's ARPA-sponsored natural language understanding project and two Technical Notes: 'KLONE's Progress,' by R.J. Brachman, and 'Generalizations of ATN Grammars,' by W.A. Woods. The Annual summary includes a list o...

W. A. Woods R. J. Brachman

1978-01-01

407

Peri-Saccadic Natural Vision  

PubMed Central

The fundamental role of the visual system is to guide behavior in natural environments. To optimize information transmission, many animals have evolved a non-homogeneous retina and serially sample visual scenes by saccadic eye movements. Such eye movements, however, introduce high-speed retinal motion and decouple external and internal reference frames. Until now, these processes have only been studied with unnatural stimuli, eye movement behavior, and tasks. These experiments confound retinotopic and geotopic coordinate systems and may probe a non-representative functional range. Here we develop a real-time, gaze-contingent display with precise spatiotemporal control over high-definition natural movies. In an active condition, human observers freely watched nature documentaries and indicated the location of periodic narrow-band contrast increments relative to their gaze position. In a passive condition under central fixation, the same retinal input was replayed to each observer by updating the video’s screen position. Comparison of visual sensitivity between conditions revealed three mechanisms that the visual system has adapted to compensate for peri-saccadic vision changes. Under natural conditions we show that reduced visual sensitivity during eye movements can be explained simply by the high retinal speed during a saccade without recourse to an extra-retinal mechanism of active suppression; we give evidence for enhanced sensitivity immediately after an eye movement indicative of visual receptive fields remapping in anticipation of forthcoming spatial structure; and we demonstrate that perceptual decisions can be made in world rather than retinal coordinates.

Dorr, Michael; Bex, Peter J.

2013-01-01

408

Natural Inhibitors of Maillard Browning.  

National Technical Information Service (NTIS)

This report documents research of a novel natural means of inhibiting Maillard browning, also known as non-enzymatic browning, a complex reaction which can lead to darkening of color, off-odors, off-flavors, and nutritive degradation in food. These effort...

J. LeBlanc L. Pecukonis N. F. Farhadi

2013-01-01

409

Adaptation to natural flow regimes  

Microsoft Academic Search

Floods and droughts are important features of most running water ecosystems, but the alteration of natural flow regimes by recent human activities, such as dam building, raises questions related to both evolution and conservation. Among organisms inhabiting running waters, what adaptations exist for surviving floods and droughts? How will the alteration of the frequency, tim- ing and duration of flow

David A. Lytle; N. LeRoy Poff

2003-01-01

410

Natural Dyes. Third World Science.  

ERIC Educational Resources Information Center

This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

Jones, Natalie; Hughes, Wyn

411

EIA's Natural Gas Production Data  

EIA Publications

This special report examines the stages of natural gas processing from the wellhead to the pipeline network through which the raw product becomes ready for transportation and eventual consumption, and how this sequence is reflected in the data published by the Energy Information Administration (EIA).

Information Center

2009-04-09

412

Galactic Rotation and Natural Law  

NASA Astrophysics Data System (ADS)

There exist a number of striking empirical regularities in the kinematics of rotating galaxies. These include flat rotation curves, the Tully-Fisher relation, and a relation between gravitational force and baryonic surface density. I suggest that these may be tantamount to Natural Laws, analogous to Kepler's Laws. The physical interpretation of these Laws is fraught with peril.

McGaugh, Stacy S.

2012-05-01

413

INACTIVATION OF NATURALLY OCCURRING ENTEROVIRUSES  

EPA Science Inventory

The goal of this project was to compare the kinetics of chlorine inactivation of a naturally-shed virus and its tissue culture grown counterpart. Since inactivation studies require purified preparation possessing high infectivity titer and low chlorine demand a major part of this...

414

The Nature of Adventure Education.  

ERIC Educational Resources Information Center

Man answers a natural call for adventure in many ways including escape into fantasy, vertigo seeking, kinetic euphoria, and by exercising the pioneer spirit. Adventure education can help equip people to satisfy their need for adventure in meaningful, enriching ways. A reaction to unsatisfactory educational milieus, adventure education has emerged…

Cousineau, Claude

415

Nature Online Video Streaming Archive  

NSDL National Science Digital Library

Nature is an international, interdisciplinary, weekly peer-reviewed journal of science that has an impressive website that conveys its information in written, audio or video formats. The video offerings here "feature interviews with scientists behind the research and analysis from Nature editors." Nature also has a YouTube channel that can be used to "upload and share our videos across the Internet through websites, mobile devices, blogs and email." Visitors will note that most, but not all, of the videos in the video archive have "free access" next to the title of the video. Some of the pay videos are available via iTunes. When visitors click on a video in the video archive, they will find that they can choose to watch the video in high or low quality and they can download the required Flash Plugin, if needed. Additionally, visitors will find a section entitled "Background Information", which gives links to Nature podcasts and articles about the research presented in the video.

416

Natural history museums and cyberspace  

USGS Publications Warehouse

Natural history museums are entering the electronic age as they increasingly use computers to build accessible and shareable databases that support research and education on a world-wide basis. Museums are exploring the Internet and other shared uses of electronic media to enhance their traditional roles in education, training, identifications, technical assistance, and collections management.

Wemmer, C.; Erixon-Stanford, M.; Gardner, A.L.

1996-01-01

417

Dimensional stability of natural fibers  

SciTech Connect

One of the main problems associated with the use of natural fibers as reinforcing agents in composites is their uptake of moisture. Many natural fibers are lignocellulosic, which causes them to swell and shrink as the amount of available moisture changes. Swelling and shrinking can cause composites to prematurely fail. This paper presents the results of a preliminary study that considers the use of two different low molecular weight monomers, hydroxyethyl methacrylate (HEMA) and hydroxyethyl acrylate (HEA), polymerized by electron beam ionizing radiation, to dimensionally stabilize natural fibers. Eight different treatments consisting of varying amounts of monomer, encapsulating agent, and cross-linkers, were evaluated for their ability to dimensionally stabilize sisal fiber. Results indicate that both polymerized HEA and HEMA can reduce the swelling of sisal fiber. The effectiveness of HEA and HEMA can be further enhanced with the use of a cross-linker (SR 454). The use of hydroxylated monomers to dimensionally stabilize natural fibers may play an important role in reducing delamination and improving fiber-resin adhesion in composites.

Driscoll, Mark S. [Ultraviolet Light/Electron Beam (UV/EB) Technology Center, State University of New York College of Environmental Science and Forestry (SUNY-ESF), 1 Forestry Drive, Syracuse, NY 13210 (United States); Smith, Jennifer L.; Woods, Sean; Tiss, Kenneth J. [Ultraviolet Light/Electron Beam (UV/EB) Technology Center, State University of New York College of Environmental Science and Forestry (SUNY-ESF), 1 Forestry Drive, Syracuse, NY 13210 and Sustainable Construction Management and Engineering, SUNY-ESF (United States); Larsen, L. Scott [New York State Energy Research and Development Authority (NYSERDA), 17 Columbia Circle, Albany, NY 12203 (United States)

2013-04-19

418

San Diego Natural History Museum  

NSDL National Science Digital Library

The San Diego Natural History Museum traces its roots to a group of amateur naturalists, who formed the San Diego Society of Natural History in 1874. Today the Museum strives to help visitors interpret the natural world through research, education and exhibits. Active research in scientific field work and systematics has been ongoing since the Societies inception, and current fields of interest include Entomology, Botany, Geology, Mineralogy, Paleontology, and Birds and Mammals. The Museum offers an online specimen database, as well as information on publications, collections care and conservation, symposia and workshops and bi-national expeditions. There are a number of changing exhibits at the facility, and one can bring nature into your classroom, art studio, and home by becoming a member of the Museum's Loan Program. The program has over 1100 specimens that represent biologic and geologic diversity throughout the world. The Museums program Proyecto Bio-regional de Educación Ambiental, or PROBEA, designs innovative environmental education curricula to train educators, and engage teachers, students and others in projects to benefit their local environment.

419

The mineral nature of asbestos  

Microsoft Academic Search

Fibrous minerals are common in nature but asbestiform minerals are rare. The unique mineralogical characteristic common to all the asbestos minerals is their morphologic form (or habit of crystallization) as polyfilamentous fiber bundles. The individual fibrils within the bundles have a tendency to be very long with a narrow range of diameters and grow with their long fiber axis in

Malcolm Ross; Arthur M. Langer; Gordon L. Nord; Robert P. Nolan; Richard J. Lee; D. Van Orden; John Addison

2008-01-01

420

Getting in Sync with Nature  

ERIC Educational Resources Information Center

The current time "measuring system" has taken on a life of its own, bearing only an approximate resemblance to the natural occurrences it set out to measure. The "analemma equation of time" was created to precisely set our clocks by converting irregular sun time to the even, regular tempo of mean time. In this article, the equation is described in…

Fisher, Diane; Novati, Alex; Schugart, Gene

2004-01-01

421

Natural System of Eolian Landforms.  

National Technical Information Service (NTIS)

On the basis of the natural system of exogenic landforms, it is possible to arrange genetically all known eolian landforms, taking into account the system of fluvial landforms and the results of investigations on blown sands of R. A. Bagnold. The framewor...

L. Kadar

1977-01-01

422

Natural products: DNA double whammy  

NASA Astrophysics Data System (ADS)

The lomaiviticins are exceedingly potent antibiotic agents, but the mechanism responsible for this activity has so far been unclear. Now, efficient generation of double-strand breaks in DNA by lomaiviticin A has been linked to the remarkable cytotoxicity of these diazobenzofluorene-containg natural products.

Gates, Kent S.

2014-06-01

423

Monitored Natural Attenuation of Explosives  

Microsoft Academic Search

Explosives are subject to several attenuation processes that potentially reduce concentrations in groundwater over time. Some of these processes are well defined, while others are poorly understood. The objective of the project was to optimize data collection and processing procedures for evaluation and implementation of monitored natural attenuation of explosives. After conducting experiments to optimize data quality, a protocol was

Judith C. Pennington; James M. Brannon; Douglas Gunnison; D. W. Harrelson; M. Zakikhani; Paul Miyares; Thomas F. Jenkins; Joan Clarke; Charolett Hayes; David Ringleberg; Ed Perkins; Herb Fredrickson

2001-01-01

424

The last vestiges of naturalness  

NASA Astrophysics Data System (ADS)

Direct LHC bounds on colored SUSY particles now corner naturalness more than the measured value of the Higgs mass does. Bounds on the gluino are of particular importance, since it radiatively "sucks" up the stop and Higgs-up soft masses. As a result, even models that easily accommodate a 125 GeV Higgs are almost as tuned as the simplest version of SUSY, the MSSM: at best at the percent level. In this paper, we further examine how current LHC results constrain naturalness in three classes of models that may relax LHC bounds on sparticles: split families, baryonic RPV, and Dirac gauginos. In models of split families and bRPV, the bounds on the gluino are only slightly reduced, resulting in a few percent tuning. In particular, having a natural spectrum in bRPV models typically implies that tops, W s, and Zs are easily produced in the cascade decays of squarks and gluinos. The resulting leptons and missing energy push the gluino mass limit above 1 TeV. Even when the gluino has a Dirac mass and does not contribute to the stop mass at one loop, tuning reappears in calculable models because there is no symmetry imposing the supersoft limit. We conclude that, even if sparticles are found at LHC-14, naturalness will not emerge triumphant.

Arvanitaki, Asimina; Baryakhtar, Masha; Huang, Xinlu; Van Tilburg, Ken; Villadoro, Giovanni

2014-03-01

425

Natural Selection and Applied Genetics  

NSDL National Science Digital Library

Natural Selection and Applied Genetics is a graduate-level professional development course designed to enhance your understanding and teaching of life science. In two sessions, you will investigate life science topics using hands-on activities and online resources including video segments, interactive activities, readings, and other multimedia materials. These resources are drawn from Teachers' Domain, WGBH's digital library service.

2010-01-01

426

Visualizing and quantifying natural selection  

Microsoft Academic Search

Modern methods of analysis are enabling researchers to study natural selection at a new level of detail. Multivariate statistical techniques can Identify specific targets of selection and provide parameter estimates that fit into equations for evolutionary change. A more Intuitive understanding of the form of selection can be provided through graphical representation of selection surfaces. Combinations of quantitative and visual

Edmund D. Brodie; Allen J. Moore; Fredric J. Janzen

1995-01-01

427

Exact law of live nature  

NASA Astrophysics Data System (ADS)

Exact law of mortality dynamics in changing populations and environment is derived. It includes no explicit characteristics of animal- environment interactions (metabolism etc) which are a must for life; it is universal for all animals, from single cell yeast to humans, with their drastically different biology, evolutionary history, and complexity; it is rapidly (within few percent of life span) reversible. Such law is unique for live systems with their homeostatic self-adjustment to environment (cf. thermodynamics of liquids and glasses). The law which is valid for all live, and only live, systems is their specific natural law. Mortality is an instrument of natural selection and biological diversity. Its law, which is preserved in evolution of all species, is a conservation law of mortality, selection, evolution, biology. The law implies new kind of intrinsic mortality and adaptation which dominate in evolutionary unprecedented protected populations and, in contrast to species specific natural selection, proceed via universal stepwise rungs and reduce to universal cellular mechanism. The law demonstrates that intrinsic mortality and at least certain aspects of aging are disposable evolutionary byproducts, and directed genetic and/or biological changes may yield healthy and vital Methuselah lifespan. This is consistent with experiments. Universality implies that single cell yeast may provide a master key to the cellular mechanism of universal mortality, aging, selection, evolution, and its regulation in all animals. One may look for its manifestations in animal cells also, e.g., in their replicative senescence and cancer. Evolutionary origin and genetic nature of universality are suggested.

Azbel, Mark Ya.

2005-07-01

428

Natural Recovery from Substance Dependency  

Microsoft Academic Search

The literature on cessation of drug and alcohol dependency without benefit of treatment or participation in self-help groups spans nearly forty years. While this literature is substantial and analyses of the processes of natural recovery well-developed, discussions directed at treatment providers around the value of these analyses for practice has been sparse. Drawing on our study as well as the

William Cloud; Robert Granfield

2001-01-01

429

First natural occurrence of coesite  

USGS Publications Warehouse

Coesite, the high-pressure polymorph of SiO2, hitherto known only as a synthetic compound, is identified as an abundant mineral in sheared Coconino sandstone at Meteor Crater, Arizona. This natural occurrence has important bearing on the recognition of meteorite impact craters in quartz-bearing geologic formations.

Chao, E. C. T.; Shoemaker, E. M.; Madsen, B. M.

1960-01-01

430

Staff Handbook on Natural Gas.  

ERIC Educational Resources Information Center

The Department of Commerce created a Natural Gas Action Group early in the fall of 1975 to assist industrial firms and the communities they serve to cope with the effects of potentially severe and crippling curtailment situations. This action group was trained to assess a specific local situation, review the potential for remedial action and…

Gorges, H. A., Ed.; Raine, L. P., Ed.

431

Monophyly, Paraphyly, and Natural Kinds  

Microsoft Academic Search

A long-standing debate has dominated systematic biology and the ontological commitments made by its theories. The debate has contrasted individuals and the part – whole relationship with classes and the membership relation. This essay proposes to conceptualize the hierarchy of higher taxa is terms of a hierarchy of homeostatic property cluster natural kinds (biological species remain largely excluded from the

Olivier Rieppel

2005-01-01

432

Semiconductor properties of natural melanins.  

PubMed

Basic semiconductor characteristics of natural melanins isolated from bovine eye, human dark hair, and banana peel were obtained by means of the dc dark conductivity experiments and optical absorption measurements. The results were compared with results obtained for synthetic melanin. Specific conductivity in natural melanins is of the order 10(-11) omega -1 cm-1 and in synthetic melanin 10(-8) omega -1 cm-1. Thermal activation energies in the range 298-333 degrees K are eye melanin, 0.93 eV; hair melanin, 1.01 eV; banana melanin, 1.04 eV; whereas synthetic melanin has two values of activation energy: up to 311 degrees K, 0.1 eV; above 313 degrees K, 0.78 eV. Optical gaps are: in eye melanin, 1.73 eV; in hair melanin, 1.35 eV; in banana melanin, 1.55 eV; and in synthetic melanin, 1.40 eV. The observed differences between natural melanins and the synthetic one could be explained by either the presence of protein residues in natural melanins or the influence of the isolation method on their electrical properties. PMID:7185058

Strzelecka, T

1982-01-01

433

Raman spectroscopy of natural oxalates  

Microsoft Academic Search

Evidence for the existence of primitive life forms such as lichens and fungi can be based upon the formation of oxalates which are most readily detected using Raman spectroscopy. A comparative study of a suite of natural oxalates including weddellite, whewellite, moolooite, humboldtine, glushinskite, natroxalate and oxammite has been undertaken using Raman spectroscopy. The minerals are characterised by the wavenumber

R. L Frost

2004-01-01

434

A classification of natural rivers  

Microsoft Academic Search

A classification system for natural rivers is presented in which a morphological arrangement of stream characteristics is organized into relatively homogeneous stream types. This paper describes morphologically similar stream reaches that are divided into 7 major stream type categories that differ in entrenchment, gradient, width\\/depth ratio, and sinuosity in various landforms. Within each major category are six additional types delineated

David L. Rosgen

1994-01-01

435

Nurturing the Nature of Science  

ERIC Educational Resources Information Center

Historical stories of scientists provide an excellent opportunity to help students see that science is indeed a human endeavor and demonstrate the interrelationships among science, technology, and society. A number of engaging historical accounts illustrate characteristics of the nature of science. The story of Lise Meitner leads students through…

Reeves, Carolyn; Chessin, Debby; Chambless, Martha

2007-01-01

436

Natural gas monthly, January 1997  

SciTech Connect

This publication, the Natural Gas Monthly, presents the most recent data on natural gas supply, consumption, and prices from the Energy Information Administration (EIA). Of special interest in this issue are two articles summarizing reports recently published by EIA. The articles are {open_quotes}Natural Gas Productive Capacity{close_quotes} and {open_quotes}Outlook for Natural Gas Through 2015,{close_quotes} both of which precede the {open_quotes}Highlights{close_quotes} section. With this issue, January 1997, changes have been made to the format of the Highlights section and to several of the tabular and graphical presentations throughout the publication. The changes to the Highlights affect the discussion of developments in the industry and the presentation of weekly storage data. An overview of the developments in the industry is now presented in a brief summary followed by specific discussions of supply, end-use consumption, and prices. Spot and futures prices are discussed as appropriate in the Price section, together with wellhead and consumer prices.

NONE

1997-01-01

437

Analyses of Natural Gases, 1972.  

National Technical Information Service (NTIS)

This publication contains routine analyses and related source data for 299 natural gas samples from 22 states and three foreign countries. All samples were collected during Calendar Year 1972 as a part of a continuous survey of the free world for occurren...

L. E. Cardwell L. F. Benton

1973-01-01

438

Analyses of Natural Gases, 1981.  

National Technical Information Service (NTIS)

This Bureau of Mines publication contains analyses and related source data for 224 natural gas samples from 18 States. Of the total, 191 samples were collected during calendar year 1981. The remaining 33 samples were collected during previous years, but r...

R. D. Miller F. R. Hertweck

1982-01-01

439

Illicit Trafficking of Natural Radionuclides  

SciTech Connect

Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

Friedrich, Steinhaeusler; Lyudmila, Zaitseva [Div. of Physics and Biophysics, University of Salzburg Hellbrunnerstr. 34, A 5020 Salzburg (Austria)

2008-08-07

440

The surface learned from nature  

NASA Astrophysics Data System (ADS)

In this work, I would like to introduce the emerging surface of nature. The surface in nature, has the multi and optimized function with well organized structure. There are so many examples that we learn and apply to technology. First example is self-cleaning surface. Some plants (such as lotus leaf, taro leaf) and the wings of many large-winged insects (such as moth, butterfly, dragonfly) remain their surface clean in the very dirty environment. This self cleaning effect is accomplished by the superhydrophobic surfaces which exhibit the water contact angle of more than 150° with low sliding angle. Generally, the superhydrophobic surface is made up the two factors. One is the surface composition having the low surface tension energy. The other is the surface morphology of hierarchical structure of micro and nano size. Because almost nature surface have the hierarchical structures range from macro to nano size, their topography strength their function to adjust the life in nature environment. The other example is the surface to use for drag reduction. The skin friction drag causes eruptions of air or water resulting in greater drag as the speed is increased. This drag requires more energy to overcome. The shark skin having the fine sharp-edged grooves about 0.1 mm wide known riblet reduces in skin friction drag by being far away the vortex. Among a lot of fuctional surface, the most exciting surface the back of stenocara a kind of desert beetles. Stenocara use the micrometre-sized patterns of hydrophobic, wax-coated and hydrophilic, non-waxy regions on their backs to capture water from fog. This fog-collecting structure improves the water collection of fog-capture film, condenser, engine, and future building. Here, the efforts to realize these emerging functional surfaces in nature on technology are reported with the fabrication method and their properties, especially for the control of surface wettability.

Lim, H.; Kim, W. D.

2010-07-01

441

Illicit Trafficking of Natural Radionuclides  

NASA Astrophysics Data System (ADS)

Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s) (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

Friedrich, Steinhäusler; Lyudmila, Zaitseva

2008-08-01

442

Ambiente e formação estelar em galáxias  

NASA Astrophysics Data System (ADS)

Estudamos o ambiente de galáxias com formação estelar inicialmente a partir de uma amostra limitada em volume proveniente do 2dF Galaxy Redshift Survey. Discriminamos as galáxias com formação estelar com base em distintas classes espectrais, utilizando para esta classificação as larguras equivalentes das linhas [OII]l3727 e Hd. O ambiente é caracterizado pela densidade espacial local de galáxias. Mostramos que a fração de galáxias com formação estelar é bastante reduzida em ambientes densos, enquanto a de galáxias passivas aumenta nestas regiões. Por outro lado, quando analisamos a fração de galáxias que apresentam um surto recente de formação estelar, notamos que ela independe do ambiente, sendo que em regiões mais densas alguns destes objetos apresentam distorções em sua morfologia. Estes resultados são confrontados com a análise da dependência ambiental da taxa de formação estelar, estimada pela emissão em Ha, de uma amostra extraída do Sloan Digital Sky Survey. Um declínio gradual da formação estelar também é observado nesta análise, sugerindo que as interações por efeitos de maré sejam responsáveis pela redução da formação estelar em ambientes densos através da remoção do reservatório de gás das galáxias. No entanto, estas interações também podem induzir surtos de formação estelar nas galáxias, além de peculiaridades morfológicas observadas nos objetos que habitam regiões mais densas.

Mateus, A., Jr.; Sodré, L., Jr.

2003-08-01

443

EM International, July 1994, Volume 2  

SciTech Connect

The Office of Environmental Management (EM) at the Department of Energy (DOE) is seeking out and leveraging foreign technology, data, and resources in keeping with EM`s mandate to protect public health and the environment through the safe and cost-effective remediation of the Department`s nuclear weapons sites. EM works closely with foreign governments, industry, and universities to obtain innovative environmental technologies, scientific and engineering expertise, and operations experience that will support EM`s objectives. Where appropriate, these international resources are used to manage the more urgent risks at our sites, secure a safe workplace, help build consensus on critical issues, and strengthen our technology development program. Through international agreements EM engages in cooperative exchange of information, technology, and individuals. Currently, we are managing agreements with a dozen countries in Europe, Latin America, and Asia. These agreements focus on environmental restoration, waste management, transportation of radioactive wastes, and decontamination and decommissioning. This publication contains the following articles: in situ remediation integrated program; in-situ characterization and inspection of tanks; multimedia environmental pollutant assessment system (MEPAS); LLNL wet oxidation -- AEA technology. Besides these articles, this publication covers: EU activities with Russia; technology transfer activities; and international organization activities.

Not Available

1994-10-01

444

On the Nature of Consciousness-On Consciousness in Nature  

NASA Astrophysics Data System (ADS)

The study of consciousness has considerably increased in the last few years. Research has been mainly focused on its neurological aspects, but the intrinsic nature of consciousness is usually completely neglected. In this contribution, we present a new onto-epistemological general metamodel that we developed to interpret complex partly autonomous systems (like living systems). Our metamodel is not based on the usual space-time-energy framework of mainstream Newtonian science, but involves two elemental categories: the domain of objects and the domain of relations. Furthermore, and most importantly, we show that the combination of these two aspects gives rise to the system as a holistic, self-referential and existential entity. We will then use this onto-epistemology to interpret the nature of consciousness, which, in this model, is a meta-physical, meta-relational self-referential entity.

Schwarz, Eric

2010-11-01

445

Natural radioactivity in phosphates, phosphogypsum and natural waters in Morocco.  

PubMed

The contents of natural radionuclides (uranium, actinium and thorium series) were measured in sedimentary phosphate rock samples using high-resolution gamma spectrometry. Data obtained for uranium content (ppm) were compared with the results obtained by a method based on the measurements using solid-state nuclear track detectors (SSNTD) in the same samples. The potential leaching of radionuclides from sedimentary phosphate rock during the industrial production of the phosphoric acid was studied. The process of leaching of the radioisotopes from phosphogypsum was discussed. A method for the direct alpha counting of 226Ra thin source, elaborated by the deposition of Ra from aqueous solutions on manganese oxides film deposited on polyvinyl support, have been developed and applied for the determination of 226Ra in natural water samples. The results show that only the water sample from the mine area reveals the presence of 226Ra at a level of about 0.2 Bq l-1. PMID:11378917

Azouazi, M; Ouahidi, Y; Fakhi, S; Andres, Y; Abbe, J C; Benmansour, M

2001-01-01

446

Natural and nature-inspired semiconductors for organic electronics  

NASA Astrophysics Data System (ADS)

Herein we report our recent efforts in employing natural materials and synthetic derivatives of natural molecules for organic field effect transistors (OFETs) and organic photovoltaics (OPVs). We evaluated dyes from the following chemical families: acridones, anthraquinones, carotenoids, and indigoids. These materials have proven effective in organic field effect transistors, with mobilities in the 4 × 10-4 - 0.2 cm2/V-s range, with indigoids showing promising ambipolar behavior. We fabricated complementary-like voltage inverters with high gains using indigoids. The photovoltaic properties of these materials were characterized in metal-insulator-metal (MIM) diodes, as well as in donoracceptor bilayer devices. Additionally, we have found that indigoids and Quinacridone, show long-range crystalline order due to hydrogen binding, and have considerably higher relative permittivities (?) compared to typical organic semiconductors. Higher permittivities result in lower exciton binding energies and thus may lead to high photocurrents in photovoltaic devices.

Glowacki, Eric Daniel; Leonat, Lucia; Voss, Gundula; Bodea, Marius; Bozkurt, Zeynep; Irimia-Vladu, Mihai; Bauer, Siegfried; Sariciftci, Niyazi Serdar

2011-09-01

447

New trends in natural language processing: statistical natural language processing.  

PubMed

The field of natural language processing (NLP) has seen a dramatic shift in both research direction and methodology in the past several years. In the past, most work in computational linguistics tended to focus on purely symbolic methods. Recently, more and more work is shifting toward hybrid methods that combine new empirical corpus-based methods, including the use of probabilistic and information-theoretic techniques, with traditional symbolic methods. This work is made possible by the recent availability of linguistic databases that add rich linguistic annotation to corpora of natural language text. Already, these methods have led to a dramatic improvement in the performance of a variety of NLP systems with similar improvement likely in the coming years. This paper focuses on these trends, surveying in particular three areas of recent progress: part-of-speech tagging, stochastic parsing, and lexical semantics. PMID:7479725

Marcus, M

1995-10-24

448

Natural Selection: Introduction to the Nature of Explanatory Models  

NSDL National Science Digital Library

This information is designed to connect what students have learned about scientific arguments to the role and nature of explanatory models in science. They will be asked to read and discuss a brief handout about scientific models and their function in science. They will discover that models are ideas that scientists use to explain patterns they see in the natural world, a model is an idea that has predictive and explanatory power and is consistent with other ideas about how the world works, and that models can be compared based on data, the inferences made in the model, and the prior knowledge and beliefs upon which they are based. This site includes instructional notes for the teacher and student handouts.

449

Project X RFQ EM Design  

SciTech Connect

Project X is a proposed multi-MW proton facility at Fermi National Accelerator Laboratory (FNAL). The Project X front-end would consist of an H- ion source, a low-energy beam transport (LEBT), a CW 162.5 MHz radio-frequency quadrupole (RFQ) accelerator, and a medium-energy beam transport (MEBT). Lawrence Berkeley National Laboratory (LBNL) and FNAL collaboration is currently developing the designs for various components in the Project X front end. This paper reports the detailed EM design of the CW 162.5 MHz RFQ that provides bunching of the 1-10 mA H- beam with acceleration from 30 keV to 2.1 MeV.

Romanov, Gennady; /Fermilab; Hoff, Matthew; Li, Derun; Staples, John; Virostek, Steve; /LBNL

2012-05-09

450

Nature of Stationarity of the Natural Frequencies at the Natural Modes in the RAYLEIGH-RITZ Method  

NASA Astrophysics Data System (ADS)

A variational formulation of the Rayleigh-Ritz method to obtain approximate natural frequencies and natural modes is presented. The stationarity of the natural frequencies with respect to the arbitrary coefficients in the linear combination of the assumed deflection shapes, and also at the natural modes is investigated. It is concluded that the natural frequencies are stationary and need not always be minimum, with respect to the arbitrary coefficients; however, they are minimum with respect to the natural modes. This may provide a means of checking the accuracy of the computed natural frequencies obtained by using energy techniques such as the Rayleigh-Ritz, Galerkin, and finite element methods.

Bhat, R. B.

1997-06-01

451

Natural antioxidants for radiation vulcanization of natural rubber latex  

Microsoft Academic Search

The anti-oxidant properties of some non-water soluble amino acids were tested on radiation vulcanized natural rubber latex (RVNRL). Among these were cystine, tyrosine, asparagine phenyl alanine and alanine. The results indicate that all of these amino acids have anti-oxidant properties with cystine, alanine and asparagine, phenyl alanine exhibiting higher anti-aging properties on RVNRL. Combinations of these amino acids improved the

L. V. Abad; L. S. Relleve; C. T. Aranilla; A. K. Aliganga; A. M. dela Rosa

2002-01-01

452

Type I natural killer T cells: naturally born for fighting  

Microsoft Academic Search

Type ? natural killer T cells (NKT cells), a subset of CD1d-restricted T cells with invariant V?? TCR, are characterized by prompt production of large amounts of Th1 and\\/or Th2 cytokines upon primary stimulation through the TCR complex. The rapid release of cytokines implies that type ? NKT cells may play a critical role in modulating the upcoming immune responses,

Jin-quan Tan; Wei Xiao; Lan Wang; Yu-ling He

2010-01-01

453

Why are natural disasters not 'natural' for victims?  

SciTech Connect

Some type of formal or informal social assessment is often carried out in the wake of natural disasters. One often-observed phenomenon in such situations is that disaster victims and their sympathizers tend to focus on those elements of disasters that might have been avoided or mitigated by human intervention and thus assign 'undue' levels of responsibility to human agents. Often the responsibility or blame is directed at the very government agencies charged with helping people cope with and recover from the event. This phenomenon presents particular challenges for those trying to understand the social impacts of such events because of the reflexive nature of such analysis. Often the social analyst or even the government agency manager must sort through such perceptions and behavior and (at least implicitly) make judgments about which assignments of responsibility may have some validity and which are largely the result of the psychology of the disaster itself. This article presents a conceptual framework derived largely from social psychology to help develop a better understand such perceptions and behavior. While no 'magic bullet' formula for evaluating the validity of disaster victims' claims is presented, the conceptual framework is presented as a starting point for understanding this particular aspect of the psychology of natural disasters.

Kumagai, Yoshitaka [Akita International University, Yuwa-machi, Akita (Japan); Edwards, John [Department of Psychology, Oregon State University, Corvallis, OR 97332 (United States); Carroll, Matthew S. [Department of Natural Resource Sciences, Washington State University, Johnson Hall 183, P.O. Box 646410, Pullman, WA 99164 (United States)]. E-mail: carroll@mail.wsu.edu

2006-01-15

454

Manufacturing Methods of Multi-ingredient Compost with EM  

Microsoft Academic Search

This project is performed for increasing the integrated effect of EM by reasonable mixing of EM solution and multi-ingredient compost in agriculture. This compost has been manufactured by treating organic materials with EM and culturing other beneficial bacteria with high density, and by adding some minerals. The organic substrates were fermented by EM. There was a definite difference between organic

H. G. Ryang; M. S. Rim; Y. H. Rim; C. U. Chang; C. G. Kang; D. C. Yang

455

Rainfall Induced Natural Disaster in Central America, a challenge for Regional Risk Management  

NASA Astrophysics Data System (ADS)

Rainfall induced natural disasters rank first among all natural disasters in Central America. According to the records of the EM-DAT international database, 248 out of 486 disasters registered in Central America were disasters triggered by rainfall invents, in countries like Belize and Honduras, rainfall-induced natural disasters, mainly floods and landslides, account for more than 90% of the total number of casualties as well as the economic damage of all the disasters. Due to the natural conditions of the Central American Isthmus, precipitation events often struck more than one country at the time, for example Hurricane Mitch in 1998 affected the entire Central American region causing more than 18,000 casualties. In this context, the Central America countries have been working on joint programs and policies aiming transboundary cooperation and management of natural disasters, a clear example of this effort is CEPREDENAC which is the intergovernmental body with the mandate of promoting activities, projects and programs towards reduction of the risks to disasters in order to avoid loss of life and economic assets in the Central America, however, transnational management face several challenges that fall mostly in the political, economical and technical areas. In this paper we described and analyzed the rainfall induced natural disasters, their impacts and the inherent management challenges in the Central American context. Key words: Central America, Natural Disasters, Risk Management, International Cooperation

Estuardo Guinea Barrientos, Héctor; Swain, Ashok

2013-04-01

456

An EM algorithm based on an internal list for estimating haplotype distributions of rare variants from pooled genotype data  

PubMed Central

Background Pooling is a cost effective way to collect data for genetic association studies, particularly for rare genetic variants. It is of interest to estimate the haplotype frequencies, which contain more information than single locus statistics. By viewing the pooled genotype data as incomplete data, the expectation-maximization (EM) algorithm is the natural algorithm to use, but it is computationally intensive. A recent proposal to reduce the computational burden is to make use of database information to form a list of frequently occurring haplotypes, and to restrict the haplotypes to come from this list only in implementing the EM algorithm. There is, however, the danger of using an incorrect list, and there may not be enough database information to form a list externally in some applications. Results We investigate the possibility of creating an internal list from the data at hand. One way to form such a list is to collapse the observed total minor allele frequencies to “zero” or “at least one”, which is shown to have the desirable effect of amplifying the haplotype frequencies. To improve coverage, we propose ways to add and remove haplotypes from the list, and a benchmarking method to determine the frequency threshold for removing haplotypes. Simulation results show that the EM estimates based on a suitably augmented and trimmed collapsed data list (ATCDL) perform satisfactorily. In two scenarios involving 25 and 32 loci respectively, the EM-ATCDL estimates outperform the EM estimates based on other lists as well as the collapsed data maximum likelihood estimates. Conclusions The proposed augmented and trimmed CD list is a useful list for the EM algorithm to base upon in estimating the haplotype distributions of rare variants. It can handle more markers and larger pool size than existing methods, and the resulting EM-ATCDL estimates are more efficient than the EM estimates based on other lists.

2013-01-01

457

Natural Gas 1998: Issues and Trends  

NSDL National Science Digital Library

The EIA attributes a more competitive industry and increases in pipeline capacity as major factors affecting increased natural gas demand in Natural Gas 1998: Issues and Trends. According to this recently released report, Natural gas demand has increased in the United States by fourteen percent since 1990 and electric utility consumption of natural gas rose about seventeen percent from 1990 to 1998.

458

Turkey's Oil and Natural Gas Pipelines System  

Microsoft Academic Search

Turkey's natural gas (NG) production is very small and is almost all imported. Turkish natural gas production in 2000, 23 billion cubic feet (Bcf), met around 4% of domestic natural gas consumption requirements. NG consumption is estimated at around 700 Bcf in year 2002, accounting for around 17% of Turkey's total energy consumption. Turkish natural gas demand had been projected

Mustafa Balat; Nuray Ozdemir

2005-01-01

459

Consumo e Fermentação Ruminal de Proteínas em Função de Suplementação Alimentar Energética e Protéica em Novilhos1  

Microsoft Academic Search

RESUMO - Objetivou-se analisar o efeito de suplementação energética sobre o consumo e a fermentação ruminal de proteínas em dois níveis de proteína dietética (6 e 20%). Quatro novilhos mestiços fistulados no rúmen foram utilizados em um quadrado latino e os tratamentos arranjados em um fatorial 2 × 2, em que as dietas testadas constituíram-se de: A. só feno; B.

Natália Guarino; Souza Barbosa; Rogério de Paula Lana; Gulab Newandram Jham; Arnaldo Chaer Borges; Antônio Bento Mâncio; José Carlos Pereira; Juliana Silva Oliveira

460

Fontes de metionina em rações formuladas com base em aminoácidos totais ou digestíveis para frangas de reposição leves e semipesadas  

Microsoft Academic Search

RESUMO - Foram conduzidos dois experimentos com o objetivo de avaliar a utilização de duas fontes de metionina (em pó ou líquida) em rações formuladas com base em aminoácidos digestíveis ou totais para frangas de reposição leves e semipesadas, nas fases inicial (de 1 a 6 semanas de idade) e de crescimento (de 11 a 16 semanas de idade). Em

Luiz Gustavo Rombola; Douglas Emygdio de Faria; Bruno José Deponti; Flávio Henrique Araujo Silva; Daniel Emygdio de Faria Filho; Otto Mack Junqueira

2008-01-01

461

Antibody responses against Em18 and Em16 serodiagnostic markers in alveolar and cystic echinococcosis patients from northwest China.  

PubMed

Western blot analysis was carried out in order to evaluate new serodiagnostic markers, Em18 and Em16, for differentiation of alveolar echinococcosis (AE) from cystic echinococcosis (CE) using 36 serum samples from hydatid patients from Xinjiang, China, where AE and CE are both endemic and one double infection case has been reported. All AE cases except one (5/6) who exhibited a calcified lesion and a single case of double infection showed antibody responses against Em18 and Em16. Some of CE patient sera (6/22) showed antibody response against Em16 except one who showed that against Em18. Analyses of IgG subclass responses against Em18 and Em16 were carried out using all serum samples showing antibody responses against Em18 and/or Em16 (seven CE, five AE, and one AE + CE) and additional samples of three CE and 22 AE from Sichuan, China. IgG4 was the most predominant antibody subclass. Em18 and Em16 were recognized by both IgG4 and IgG1 (in most cases) or by either IgG4 or IgG1 (in minor cases) or by IgG3 (in very rare cases). Neither Em18 nor Em16 was recognized by IgG2 antibodies. The usefulness of Em18 and Em16 as potential new markers for serological differentiation of human AE and CE, respectively, is discussed. PMID:9354966

Ito, A; Wen, H; Craig, P S; Ma, L; Nakao, M; Horii, T; Pang, X L; Okamoto, M; Itoh, M; Osawa, Y; Wang, X G; Liu, Y H

1997-02-01

462

Microbial Flocculant for Nature Soda  

SciTech Connect

Microbial flocculant for nature soda has been studied. Lactobacillus TRJ21, which was able to produce an excellent biopolymer flocculant for nature soda, was obtained in our lab. The microbial flocculant was mainly produced when the bacteria laid in stationary growth phase. Fructose or glucose, as carbon sources, were more favorable for the bacterial growth and flocculant production. The bacteria was able to use ammonium sulfate or Urea as nitrogen to produce flocculant, but was not able to use peptone effectively. High C/N ratio was more favorable to Lactobacillus TRJ21 growth and flocculant production than low C/N ratio. The biopolymer flocculant was mainly composed of polysaccharide and protein with a molecular weight 1.38x106 by gel permeation chromatography. It was able to be easily purified from the culture medium by acetone. Protein in the flocculant was tested for the flocculating activity ingredient by heating the flocculant.

Qin, Peiyong; Zhang, Tong; Chen, Cuixian

2004-03-31

463

Nature News Special: 2012 Review  

NSDL National Science Digital Library

Nature magazine presents a yearly round-up of key science issues and discoveries, and this website provides non-subscribers access to this tremendous resource. On the website, visitors can look over the Nature's 10 feature, which provides information on the human stories behind the key developments from the year, including tales of Adam Steltzner, who made sure the Curiosity rover touched down safely on Mars. After learning about these amazing stories and people, visitors can look over the 366 Days feature. Here they can learn about the daily scientific events of the past year in a variety of media, including slide shows, instructional videos, and guided classroom activities. Additionally, the site includes Readers' Choice awards from the past year and a detailed exploration of what life might be like in 2062.

2012-12-20

464

Board on Agriculture & Natural Resources  

NSDL National Science Digital Library

Since the early 1900s, the Board on Agriculture & Natural Resources has served the United States as a unit of the National Research Council. BANR's work largely revolves around providing expert advice on "issues of food and fiber production and related matters of natural resource development, including forestry, fisheries, wildlife and land and water use." On the organization's website, visitors can learn about the events it sponsors (such as conferences and meetings), its reports, ongoing projects, and its well-known Animal Nutrition Program. The report section is well-developed and visitors can view recent works dealing with genetically engineered organisms and the nutrient requirements of nonhuman primates. Cat or dog lovers will definitely want to take a look at Petdoor, which serves as a guide for pet owners who would like information on specific nutrient needs for their animal.

465

Nebraska Department of Natural Resources  

NSDL National Science Digital Library

The Nebraska Department of Natural Resources is dedicated "to the sustainable use and proper management of Nebraska's natural resources." From its website, the generally curious can learn about its integrated water management plans, animal conservation programs, and ongoing ecological studies. The homepage has an extensive series of news releases, public notices, orders, and updates, along with ten thematic sections that cover Groundwater, Integrated Water Management, and Surface Water. Policy folks and others will enjoy the Data Bank/Maps and Data area in particular. Here, they can find interactive maps of the state, soil maps, and demographic databases that track everything from ice status on the state's rivers to agrochemical contaminants. Finally, visitors can learn about Nebraska's ongoing compacts, decrees, and interstate agreements governing water use, conservation projects, and other initiatives.

466

In search of natural quasicrystals.  

PubMed

The concept of quasicrystals was first introduced twenty-eight years ago and, since then, over a hundred types have been discovered in the laboratory under precisely controlled physical conditions designed to avoid crystallization. Yet the original theory suggested that quasicrystals can potentially be as robust and stable as crystals, perhaps even forming naturally. These considerations motivated a decade-long search for a natural quasicrystal culminating in the discovery of icosahedrite (Al(63)Cu(24)Fe(13)), an icosahedral quasicrystal found in a rock sample composed mainly of khatyrkite (crystalline (Cu,Zn)Al(2)) labeled as coming from the Koryak Mountains of far eastern Russia. In this paper, we review the search and discovery, the analysis showing the sample to be of extraterrestrial origin and the initial results of an extraordinary geological expedition to the Koryak Mountains to seek further evidence. PMID:22878708

Steinhardt, Paul J; Bindi, Luca

2012-09-01

467

In search of natural quasicrystals  

NASA Astrophysics Data System (ADS)

The concept of quasicrystals was first introduced twenty-eight years ago and, since then, over a hundred types have been discovered in the laboratory under precisely controlled physical conditions designed to avoid crystallization. Yet the original theory suggested that quasicrystals can potentially be as robust and stable as crystals, perhaps even forming naturally. These considerations motivated a decade-long search for a natural quasicrystal culminating in the discovery of icosahedrite (Al63Cu24Fe13), an icosahedral quasicrystal found in a rock sample composed mainly of khatyrkite (crystalline (Cu,Zn)Al2) labeled as coming from the Koryak Mountains of far eastern Russia. In this paper, we review the search and discovery, the analysis showing the sample to be of extraterrestrial origin and the initial results of an extraordinary geological expedition to the Koryak Mountains to seek further evidence.

Steinhardt, Paul J.; Bindi, Luca

2012-09-01

468

Naturally occurring methyl salicylate glycosides.  

PubMed

As an important part of non steroids anti-inflammation drug (NSAIDs), salicylate has developed from natural substance salicylic acid to natrium salicylicum, to aspirin. Now, methyl salicylate glycoside, a new derivative of salicylic acid, is modified with a -COOH group integrated one methyl radical into formic ether, and a -OH linked with a monosaccharide, a disaccharide or a trisaccharide unit by glycosidic linkage. It has the similar pharmacological activities, anti-inflammatory, analgesic, antipyretic and antithrombotic as the previous salicylates' without resulting in serious side effects, particularly the gastrointestinal toxicity. Owing to the superiority of those significant bioactivities, methyl salicylate glycosides have became a hot research area in NSAIDs for several years. This paper compiles all 9 naturally occurring methyl salicylate glycosides, their distribution of the resource and pharmacological mechanism, which could contribute to the new drug discovery. PMID:24329991

Mao, Ping; Liu, Zizhen; Xie, Meng; Jiang, Rui; Liu, Weirui; Wang, Xiaohong; Meng, Shen; She, Gaimei

2014-01-01

469

Natural Resources Canada: Earth Sciences  

NSDL National Science Digital Library

The Natural Resources Canada agency has created a wonderful set of resources for curious visitors seeking to learn more about the earth sciences. The agency's formal scientific research work involves divisions such as the Canada Centre for Remote Sensing, the Geodetic Survey Division, the Geological Survey of Canada, and the National Air Photo Library. On the homepage, visitors can use the Earth Sciences Resources area to find data, maps, and tools for their own research or personal edification. The site's primary materials are divided into sections that include Climate Change, Energy and Minerals, Geography and Boundaries, Groundwater, and Natural Hazards. The Geography and Boundaries area is a real find, as it provides access to the impressive Atlas of Canada, which includes 393 interactive maps and over 1,000 referenced and archived maps on all aspects of Canadian geography. Visitors should check out the Products and Services area to learn more about the maps and image services offered here.

2011-04-03

470

Alaska Museum of Natural History  

NSDL National Science Digital Library

Ever wanted to have your own volcano laboratory, but didn't want to clean up all that lava? Be a super-scientist and create your own volcano online. The Alaska Museum of Natural History is dedicated to the study and exhibition of Alaskaâs natural history and to promoting and developing educational programs which benefit students and enrich the curricula of schools and universities. The Museum focuses on Alaska's unique geological, cultural, and ecological history. In addition to Make Your Own Volcano, the website offers extensive links, resources and educational modules including Kids Activity Sheets, Dinosaurs of Alaska, the Broken Mammoth Archeological Site, and Dinosaur Tracks, which explores the information that can be gleaned from the study of footprints.

471

Nature Online Video Streaming Archive  

NSDL National Science Digital Library

Moray eels and honeybees aren't usually found in the same habitats, but they sure seem to blend well on Nature's online video archive. Designed to complement selected articles and letters from their print magazine, these videos feature analysis and commentary from Nature editors and selected scientists. This archive contains over two dozen video features that report on the honeybee genome, smoking and lung cancer genes, and the evolution of language. It's easy to see how educators might use these videos in the classroom, and even those who are just a bit curious about these topics might find themselves drawn into a certain topic. Overall, the site is a real delight, and it's one that visitors will want to recommend to friends and associates.

472

Natural Products from Mangrove Actinomycetes  

PubMed Central

Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery.

Xu, Dong-Bo; Ye, Wan-Wan; Han, Ying; Deng, Zi-Xin; Hong, Kui

2014-01-01

473

Natural products from mangrove actinomycetes.  

PubMed

Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery. PMID:24798926

Xu, Dong-Bo; Ye, Wan-Wan; Han, Ying; Deng, Zi-Xin; Hong, Kui

2014-01-01

474

The natural and perturbed troposphere  

NASA Technical Reports Server (NTRS)

A quantitative assessment of the chemical and climatic effects of industrial emissions into the atmosphere requires an understanding of the complex interactions of species within the atmosphere and of the atmosphere with other physical systems such as the oceans, lithosphere, and biosphere. The concentration of a particular species is determined by competition between various production and loss processes. The abundances of tropospheric gases are examined. The reactions of the members of the oxygen group are considered along with the models which have been developed to describe the involved relationships. Attention is also given to the natural carbon cycle, perturbations to the carbon cycle, the natural nitrogen cycle, perturbations to the nitrogen cycle, the hydrogen group, the sulfur group, and the halogen group.

Stewart, R. W.; Hameed, S.; Pinto, J.

1978-01-01

475

Natural besnoitiosis in a rabbit.  

PubMed

An adult female rabbit was submitted for necropsy after sudden death. Pneumonia and nephritis were diagnosed by gross examination. On histological examination. Besnoitia cysts were seen in the pulmonary interalveolar tissue. The Besnoitia cysts were morphologically normal in appearance, measured 127 to 185 microns in diameter and provoked mild mononuclear inflammatory reaction. To the best of our knowledge there has been no previous report of natural besnoitiosis in rabbits. PMID:8447062

Mbuthia, P G; Gathumbi, P K; Bwangamoi, O; Wasike, P N

1993-01-01

476

Natural Disaster and Technological Catastrophe  

Microsoft Academic Search

Against the backdrop of ever-expanding technological systems, the effects of accidents or breakdowns in human-made technology are examined and contrasted with those of natural disasters. A number of differences are identified, and research on these forms of cataclysmic events is reviewed. These data, as well as this analysis, suggest that technological catastrophes are more likely to have long-term effects, to

Andrew Baum; Raymond Fleming; Laura M. Davidson

1983-01-01

477

Naturalness, conformal symmetry, and duality  

NASA Astrophysics Data System (ADS)

We reconsider naturalness from the viewpoint of effective field theories, motivated by the alternative scenario that the standard model holds up to a high-energy scale such as the Planck scale. We propose a calculation scheme of radiative corrections utilizing a hidden duality, in the expectation that the unnaturalness for scalar masses might be an artifact in the effective theory and it could be improved if features of an ultimate theory are taken in.

Kawamura, Yoshiharu

2013-11-01

478

Compressed natural gas measurement issues  

Microsoft Academic Search

The Natural Gas Vehicle Coalition`s Measurement and Metering Task Group (MMTG) was established on July 1st, 1992 to develop suggested revisions to National Institute of Standards & Technology (NIST) Handbook 44-1992 (Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices) and NIST Handbook 130-1991 (Uniform Laws & Regulations). Specifically, the suggested revisions will address the sale and measurement

C. F. Blazek; J. A. Kinast; P. M. Freeman

1993-01-01

479

Scottish Natural Heritage Information Service  

NSDL National Science Digital Library

From John O' Groats to Aberdeen, the Scottish Natural Heritage's Information (SNHi) site provides detailed information on many aspects of Scotland's diverse regions, flora, and fauna. The materials on the site are divided into six sections, including the "Facts & Figures" area, which is a great place to start exploring the site. Here, visitors can learn about SNHi's work by reading their annual reports from the past several years. Users can also use an interactive map to search for special places and species.

480

Artificial intelligence and natural magic  

Microsoft Academic Search

Robotics with AI is part of a long tradition that has run from ancient times that treated the precursors of robots, the automata,\\u000a as part of Natural Magic or conjury. Deception is an integral part of AI and robotics; in some ways they form a science of\\u000a illusion. There are many robot tasks, such as caring for the elderly, minding

Noel E. Sharkey; Amanda J. C. Sharkey

2006-01-01

481

Diversity of Naturally Occurring Prokaryotes  

Microsoft Academic Search

Understanding the patterns of naturally occurring microbial diversity, how these patterns vary in space and time, and how\\u000a they relate to ecosystem structure and function, remains a significant challenge for microbiologists. A variety of levels\\u000a of microbial diversity are important and relevant from the perspective of microbial ecology, including trophic, physiological\\u000a or functional diversity, intraspecific genetic diversity, or phylogenetic diversity

E. F. Long

482

Natural Selection in the Brain  

Microsoft Academic Search

\\u000a This chapter explores the possibility that natural selection takes place in the brain. We review the theoretical and experimental\\u000a evidence for selectionist and competitive dynamics within the brain. We propose that in order to explain human problem-solving,\\u000a selectionist mechanisms demand extension to encompass the full Darwinian dynamic that arises from introducing replication\\u000a of neuronal units of selection. The algorithmic advantages

Chrisantha Fernando; Eörs Szathmáry

483

Crystallite Size in Natural Cellulose  

Microsoft Academic Search

NATURALLY occurring long thin threads of cellulose, the so-called microfibrils, vary in width from about 100 Å in bacterial, most algal and all higher plants, to more than 200 Å in some marine algae (for example, Valonia and the Cladophorales). Two schools of thought have developed concerning the internal structure of microfibrils. Ranby1, Preston2 and Ellefsen et al.3 conclude from

I. Nieduszynski; R. D. Preston

1970-01-01

484

The cost of natural selection  

Microsoft Academic Search

Summary  Unless selection is very intense, the number of deaths needed to secure the substitution, by natural selection, of one gene\\u000a for another at a locus, is independent of the intensity of selection. It is often about 30 times the number of organisms in\\u000a a generation. It is suggested that, in horotelic evolution, the mean time taken for each gene substitution

J. B. S. Haldane

1957-01-01

485

Exact law of live nature  

NASA Astrophysics Data System (ADS)

The exact law of mortality dynamics in changing populations and environment is derived. It includes no explicit characteristics of animal-environment interactions (metabolism, etc.) which are a must for life; it is universal for all animals, from single-cell yeast to humans, with their drastically different biology, evolutionary history, and complexity; it is rapidly (within few percent of life span) reversible. Such a law is unique for live systems with their homeostatic self-adjustment to environment (cf. thermodynamics of liquids and glasses). The law which is valid for all live, and only live, systems is their specific natural law. Mortality is an instrument of natural selection and biological diversity. Its law, which is preserved in evolution of all species, is a conservation law of mortality, selection, evolution, biology. The law implies new kinds of intrinsic mortality and adaptation which dominate in evolutionary unprecedented protected populations and, in contrast to species-specific natural selection, proceed via universal stepwise rungs and reduce to universal cellular mechanism. The law demonstrates that intrinsic mortality and at least certain aspects of aging are disposable evolutionary byproducts, and directed genetic and/or biological changes may yield healthy and vital Methuselah lifespan. This is consistent with experiments. Universality implies that single-cell yeast may provide a master key to the cellular mechanism of universal mortality, aging, selection, evolution, and its regulation in all animals. One may look for its manifestations in animal cells also, e.g., in their replicative senescence and cancer. Evolutionary origin and genetic nature of universality are suggested.

Azbel?, Mark Ya.

2005-08-01

486

Southern Ocean natural iron fertilization  

Microsoft Academic Search

Modeling and Synthesis of Southern Ocean Natural Iron Fertilization; Woods Hole, Massachusetts, 27--29 June 2011; For many years a major paradox in ocean science was the existence of regions where the major nutrients are present in nonlimiting concentrations yet phytoplankton biomass is low. Pioneering experiments in the 1990s firmly established that the likely cause of this high-nutrient, low-chlorophyll condition is

Matt Charette; Richard Sanders; Meng Zhou

2011-01-01

487

Marcellus Shale: Natural Gas Energy  

NSDL National Science Digital Library

This webpage from the EFMR Monitoring Group provides information on the extraction of natural gas from Pennsylvania's Marcellus Shale formation. Users may read a brief overview of the extraction efforts and the environmental concerns involved. A lesson plan and resource guide is available for download in PDF file format. The document includes a number of in-class activities for elementary, middle and high school grade levels. Academic standards and a list of links are also included.

2012-12-05

488

Fractal nature of humic materials  

SciTech Connect

Fractals are geometric representatives of strongly disordered systems whose structure is described by nonintegral dimensions. A fundamental tenet of fractal geometry is that disorder persists at any characterization scale-length used to describe the system. The nonintegral nature of these fractal dimensions is the result of the realization that a disordered system must possess more structural detail than an ordered system with classical dimensions of 1, 2, or 3 in order to accommodate this disorder within disorder.'' Thus from a fractal perspective, disorder is seen as an inherent characteristic of the system rather than as a perturbative phenomena forced upon it. Humic materials are organic substances that are formed by the profound alteration of organic matter in a natural environment. They can be operationally divided into 3 fractions; humic acid (soluble in base), fulvic acid (soluble in acid or base), and humin (insoluble in acid or base). Each of these fraction has been shown to be an extremely heterogeneous mixture. These mixtures have proven so intractable that they may represent the ultimate in molecular disorder. In fact, based on the characteristics that humic materials must possess in order to perform their functions in natural systems, it has been proposed that the fundamental chemical characteristic of a humic material is not a discrete chemical structure but a pronounced lack of order on a molecular level. If the fundamental chemical characteristic of a humic material is a strongly disordered nature, as has been proposed, then humic materials should be amenable to characterization by fractal geometry. The purpose of this paper is to test this hypothesis.

Rice, J.A. (South Dakota State Univ., Brookings, SD (United States). Dept. of Chemistry); Lin, J.S. (Oak Ridge National Lab., TN (United States))

1992-01-01

489

Fractal nature of humic materials  

SciTech Connect

Fractals are geometric representatives of strongly disordered systems whose structure is described by nonintegral dimensions. A fundamental tenet of fractal geometry is that disorder persists at any characterization scale-length used to describe the system. The nonintegral nature of these fractal dimensions is the result of the realization that a disordered system must possess more structural detail than an ordered system with classical dimensions of 1, 2, or 3 in order to accommodate this ``disorder within disorder.`` Thus from a fractal perspective, disorder is seen as an inherent characteristic of the system rather than as a perturbative phenomena forced upon it. Humic materials are organic substances that are formed by the profound alteration of organic matter in a natural environment. They can be operationally divided into 3 fractions; humic acid (soluble in base), fulvic acid (soluble in acid or base), and humin (insoluble in acid or base). Each of these fraction has been shown to be an extremely heterogeneous mixture. These mixtures have proven so intractable that they may represent the ultimate in molecular disorder. In fact, based on the characteristics that humic materials must possess in order to perform their functions in natural systems, it has been proposed that the fundamental chemical characteristic of a humic material is not a discrete chemical structure but a pronounced lack of order on a molecular level. If the fundamental chemical characteristic of a humic material is a strongly disordered nature, as has been proposed, then humic materials should be amenable to characterization by fractal geometry. The purpose of this paper is to test this hypothesis.

Rice, J.A. [South Dakota State Univ., Brookings, SD (United States). Dept. of Chemistry; Lin, J.S. [Oak Ridge National Lab., TN (United States)

1992-03-01

490

Natural Transformation of Gallibacterium anatis  

PubMed Central

Gallibacterium anatis is a pathogen of poultry. Very little is known about its genetics and pathogenesis. To enable the study of gene function in G. anatis, we have established methods for transformation and targeted mutagenesis. The genus Gallibacterium belongs to the Pasteurellaceae, a group with several naturally transformable members, including Haemophilus influenzae. Bioinformatics analysis identified G. anatis homologs of the H. influenzae competence genes, and natural competence was induced in G. anatis by the procedure established for H. influenzae: transfer from rich medium to the starvation medium M-IV. This procedure gave reproducibly high transformation frequencies with G. anatis chromosomal DNA and with linearized plasmid DNA carrying G. anatis sequences. Both DNA types integrated into the G. anatis chromosome by homologous recombination. Targeted mutagenesis gave transformation frequencies of >2 × 10?4 transformants CFU?1. Transformation was also efficient with circular plasmid containing no G. anatis DNA; this resulted in the establishment of a self-replicating plasmid. Nine diverse G. anatis strains were found to be naturally transformable by this procedure, suggesting that natural competence is common and the M-IV transformation procedure widely applicable for this species. The G. anatis genome is only slightly enriched for the uptake signal sequences identified in other pasteurellaceaen genomes, but G. anatis did preferentially take up its own DNA over that of Escherichia coli. Transformation by electroporation was not effective for chromosomal integration but could be used to introduce self-replicating plasmids. The findings described here provide important tools for the genetic manipulation of G. anatis.

Kristensen, Bodil M.; Sinha, Sunita; Boyce, John D.; Mell, Joshua C.; Redfield, Rosemary J.

2012-01-01

491

Natural transformation of Gallibacterium anatis.  

PubMed

Gallibacterium anatis is a pathogen of poultry. Very little is known about its genetics and pathogenesis. To enable the study of gene function in G. anatis, we have established methods for transformation and targeted mutagenesis. The genus Gallibacterium belongs to the Pasteurellaceae, a group with several naturally transformable members, including Haemophilus influenzae. Bioinformatics analysis identified G. anatis homologs of the H. influenzae competence genes, and natural competence was induced in G. anatis by the procedure established for H. influenzae: transfer from rich medium to the starvation medium M-IV. This procedure gave reproducibly high transformation frequencies with G. anatis chromosomal DNA and with linearized plasmid DNA carrying G. anatis sequences. Both DNA types integrated into the G. anatis chromosome by homologous recombination. Targeted mutagenesis gave transformation frequencies of >2 × 10(-4) transformants CFU(-1). Transformation was also efficient with circular plasmid containing no G. anatis DNA; this resulted in the establishment of a self-replicating plasmid. Nine diverse G. anatis strains were found to be naturally transformable by this procedure, suggesting that natural competence is common and the M-IV transformation procedure widely applicable for this species. The G. anatis genome is only slightly enriched for the uptake signal sequences identified in other pasteurellaceaen genomes, but G. anatis did preferentially take up its own DNA over that of Escherichia coli. Transformation by electroporation was not effective for chromosomal integration but could be used to introduce self-replicating plasmids. The findings described here provide important tools for the genetic manipulation of G. anatis. PMID:22582057

Kristensen, Bodil M; Sinha, Sunita; Boyce, John D; Bojesen, Anders M; Mell, Joshua C; Redfield, Rosemary J

2012-07-01

492

Bacterial symbionts and natural products  

PubMed Central

The study of bacterial symbionts of eukaryotic hosts has become a powerful discovery engine for chemistry. This highlight looks at four case studies that exemplify the range of chemistry and biology involved in these symbioses: a bacterial symbiont of a fungus and a marine invertebrate that produce compounds with significant anticancer activity, and bacterial symbionts of insects and nematodes that produce compounds that regulate multilateral symbioses. In the last ten years, a series of shocking revelations – the molecular equivalents of a reality TV show’s uncovering the true parents of a well known individual or a deeply hidden family secret – altered the study of genetically encoded small molecules, natural products for short. These revelations all involved natural products produced by bacterial symbionts, and while details differed, two main plot lines emerged: parentage, in which the real producers of well known natural products with medical potential were not the organisms from which they were originally discovered, and hidden relationships, in which bacterially produced small molecules turned out to be the unsuspected regulators of complex interactions. For chemists, these studies led to new molecules, new biosynthetic pathways, and an understanding of the biological functions these molecules fulfill.

Crawford, Jason M.; Clardy, Jon

2011-01-01

493

Antiplatelet properties of natural products.  

PubMed

Cardiovascular diseases (CVD) and its main underlying cause, atherothrombosis, are the major culprits of morbidity and mortality worldwide. Apart from the treatment of cardiovascular risk factors and the use of antithrombotic agents there is considerable interest in the role of natural food products and their bioactive components in the prevention and treatment of cardiovascular disorders. The consumption of healthy diets rich in functional foods, such as the Mediterranean diet, has shown to exert profound cardioprotective effects in the primary and secondary prevention of CVD. Moreover, accumulating data have attributed these beneficial effects, at least in part, to the modulation of key players in the pathogenesis of atherosclerosis, including amelioration in the lipid profile and vascular function and a decrease in oxidative stress and inflammation. Although with a much less clear picture, natural dietary compounds have also demonstrated to exert antiplatelet activities, further contributing to reduce the thrombotic risk. This article provides a brief overview of the atherothrombotic process to further provide an up-to-date review of the antiplatelet properties exerted by natural products and/or food-derived bioactive constituents - including ?-3 PUFA, olive oil, garlic and onions, tomatoes, mushrooms, polyphenol-rich beverages, and flavonol-rich cocoa - as well as to describe the mechanisms underlying these antiplatelet activities. PMID:23994642

Vilahur, Gemma; Badimon, Lina

2013-01-01

494

Naturally occurring anhydrovitamin A2  

PubMed Central

1. `Naturally occurring anhydrovitamin A2' obtained from the liver oil of freshwater fish Bagarius bagarius yielded, after six-stage chromatography, a pure product showing characteristic bands at 350, 368 (E1%1cm. 1006) and 390m? in ethanol, and producing a green colour with antimony trichloride (E1%1cm. 1884 at 693m?). 2. On distribution of the material between light petroleum