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1

San Marino.  

PubMed

San Marino, an independent republic located in north central Italy, in 1983 had a population of 22,206 growing at an annual rate of .9%. The literacy rate is 97% and the infant mortality rate is 9.6/1000. The terrain is mountainous and the climate is moderate. According to local tradition, San Marino was founded by a Christian stonecutter in the 4th century A.D. as a refuge against religious persecution. Its recorded history began in the 9th century, and it has survived assaults on its independence by the papacy, the Malatesta lords of Rimini, Cesare Borgia, Napoleon, and Mussolini. An 1862 treaty with the newly formed Kingdom of Italy has been periodically renewed and amended. The present government is an alliance between the socialists and communists. San Marino has had its own statutes and governmental institutions since the 11th century. Legislative authority at present is vested in a 60-member unicameral parliament. Executive authority is exercised by the 11-member Congress of State, the members of which head the various administrative departments of the goverment. The posts are divided among the parties which form the coalition government. Judicial authority is partly exercised by Italian magistrates in civil and criminal cases. San Marino's policies are tied to Italy's and political organizations and labor unions active in Italy are also active in San Marino. Since World War II, there has been intense rivalry between 2 political coalitions, the Popular Alliance composed of the Christian Democratic Party and the Independent Social Democratic Party, and the Liberty Committee, coalition of the Communist Party and the Socialist Party. San Marino's gross domestic product was $137 million and its per capita income was $6290 in 1980. The principal economic activities are farming and livestock raising, along with some light manufacturing. Foreign transactions are dominated by tourism. The government derives most of its revenue from the sale of postage stamps to collectors around the world and from payment of an annual budget subsidy by the Italian government. Despite its close ties with Italy, San Marino has maintained its distinctive status for centuries. PMID:12178101

1985-02-01

2

Manejo de los recursos costeros y marinos en América Latina y el Caribe  

Microsoft Academic Search

El presente documento (ENV-128) expone una estrategia de manejo de los recursos costeros y marinos para el Banco Interamericano de Desarrollo. El manejo costero integrado se presenta como una actividad amplia y polivalente encaminada por un lado a mejorar la calidad de vida de las comunidades que dependen de los recursos costeros y, por otro, a ayudar a los estados

Michele H. Lemay

1998-01-01

3

Population-based survey of hepatitis A virus infection in the Republic of San Marino  

Microsoft Academic Search

In 1990–1991, the prevalence of antibodies to hepatitis A virus infection (anti-HAV) was assayed by the ELISA method among 1528 apparently healthy subjects, 20–85 years old in the Republic of San Marino. Subjects were selected from the list of residents by a random stratified sampling procedure with a proportional allocation by age, sex and district of residence. The overall anti-HAV

Tommaso Stroffolini; Stefano Pretolani; Federico Miglio; Maria Rapicetta; Umbertina Villano; Fiorenza Bonvicini; Lorenzo Baldini; Francesca Sampogna; Giuliana Giulianelli; Maria Loredana Stefanelli; Alberto Carloni; Antonella Sorcinelli; Giancarlo Ghironzi; Giovanni Gasbarrini

1997-01-01

4

Karst and mixing-zone porosity in the Amposta Marino field, offshore Spain  

SciTech Connect

The offshore Amposta Marino field, located southeast of the Ebro delta, produces from the karstified Lower Cretaceous Montsia Limestone. The field is a buried-hill structure overlain by marine clastic sediments. During drowning, the buried hill was surrounded by sea water and thus represents the typical setting in which mixing-zone corrosion is a major porosity-creating process in modern carbonates (e.g., Yucatan Peninsula, Bahamas). Mixing-zone corrosion in a clastal setting differs from freshwater karstification in that it creates an essentially horizontal zone of well-connected matrix and cave porosity. This high-porosity zone is best developed on the flanks of a structure and, ideally, has a rim-like distribution. On 3-D seismic, the authors recognize a subhorizontal reflector that cuts across the gently dipping Amposta structure. This reflector was proven by seismic-to-well matching to represent a highly porous interval. Mapping of this reflector showed that it occurs somewhat discontinuously around the western margin of the structure and fairly continuously around the eastern margin, forming a clear rim feature around the flanks of the buried hill.

Wigley, P.L.; Bouvier, J.D.; Dawans, J.M. (Koninklijke/Shell Exploratie and Produktie Laboratorium, Rijswijk (Netherlands))

1988-08-01

5

Gastrópodes e outros invertebrados do sedimento e associados à macrófita Eichhornia crassipes de um açude hipertrófico do semi-árido paraibano  

Microsoft Academic Search

realizadas coletas bimestrais do sedimento (draga Van Veen, 400cm 2 ) e da planta (puçá com malha de 500µm), no período de julho\\/1998 a novembro\\/1999 e concomitantemente foram medidas as variáveis ambientais. Os gastrópodes destacam-se pela ocorrência e dominância, sendo registradas sete espécies pertencentes a seis famílias distintas. Melanoides tuberculata foi a espécie dominante em ambos os substratos (sedimento e

Francisco José Pegado Abílio; Romualdo Lunguinho Leite; Thiago Leite de Melo Ruffo

6

Metodo analitico para la determinacion de ''241 Am en muestras biologicas y sedimentos marinos mediante uso de una columna con extractante organico. (A radiochemical procedure for a low-level measurement of ''241 Am in environmental samples using a supported functional organo phosphorus extractant).  

National Technical Information Service (NTIS)

The transuranides analysis in environmental samples is carried out by CIEMAT using standardized methods based on sequential separation with ionic-exchange resins. The americium fraction is purified through a two-layer ion exchange column and lately in an ...

C. Gasco M. A. Anton A. Alvarez N. Navarro S. Salvador

1994-01-01

7

Un asteroide proveniente de la Luna  

NASA Astrophysics Data System (ADS)

El descubrimiento de un débil objeto en movimiento por el telescopio Spacewatch (un instrumento dedicado a la búsqueda de Asteroides Cercanos a la Tierra) en 1991, ha generado una gran controversia en la comunidad planetaria. El objeto, denominado 1991 VG, tiene elementos orbitales llamativamente similares a los de la Tierra, lo que ha llevado a B. G. Marsden a aventurar:``El objeto podría ser una nave espacial en retorno (IAUC 5387)". Luego de analizar las características dinámicas de 1991 VG y las diferentes hipótesis sobre su origen, favorecemos la alternativa de que el objeto es un gran fragmento de material eyectado de la Luna durante un reciente impacto (en las últimas decenas de miles de años). El hallazgo en 1983 en la Antártida de meteoritos con composición tipo lunar, confirma la posibilidad de que material de la superficie del satélite puede ser eyectado a velocidades superiores a la de escape del sistema Tierra-Luna y alcance órbitas heliocéntricas. Los elementos orbitales de 1991 VG corresponden a los valores alcanzados por partículas que apenas escapan de la gravedad lunar y entran en órbitas heliocéntricas a través del punto Lagrangiano exterior del sistema Tierra-Sol.

Tancredi, G.

8

Metales traza en sedimentos costeros de Costa Rica  

Microsoft Academic Search

Marine sediment samples from four coastal ecosystems in Costa Rica were taken between the years 2000-2002 and their iron, lead, copper and zinc concentrations were determined by the atomic absorption tech- nique with flame or graphite furnace. In the Pacific coast, Culebra Bay (Papagayo Gulf), Gulf of Nicoya, and Golfito Bay (Dulce Gulf), were selected as representative sites, and Moín

Jairo García-Céspedes; Jenaro Acuña-González; José A. Vargas-Zamora

9

(CALIDAD DEL GUANO PROVENIENTE DEL MURCIELAGO Hipposideros speoris)  

Microsoft Academic Search

SUMMARY This study aimed at assessing the physicochemical characteristics, microflora and manure quality of guano of an endemic insectivorous cave bat Hipposideros speoris. The impact of bat guano on crop growth was also assessed. Results indicated that organic matter, total carbon, total nitrogen and phosphate were high in faecal pellets. Calcium, magnesium, bacteria, actinomycetes and fungi were higher in humus-like

K. R. Sridhar; K. M. Ashwini; S. Seena; K. S. Sreepada

10

CLAVE DE LOS HONGOS MARINOS FILAMENTOSOS DE LA PROVINCIA DE BUENOS AIRES, ARGENTINA  

Microsoft Academic Search

Peña, N. I. 2000. Key to the filamentous higher marine fungi from Buenos Aires Province, Argentina. Darwiniana 38(3-4): 291-298. This contribution includes all filamentous higher marine fungi (30 Ascomycotina, 6 Deuteromycotina and 1 Basidiomycotina) cited up to the present for Buenos Aires province, wich are also the only marine fungi cited for Argentina. A dichotomous key distinguishes the species mainly

NORA I. PEÑA

2000-01-01

11

Susceptibilidad in vitro a antimicrobianos y producción de ß-lactamasas de Vibrio y Photobacterium marinos  

Microsoft Academic Search

In vitro antimicrobial susceptibilities and production of ?-lactamases in marine Vibrio and Photobacterium Four marine strains of Vibrio and Photobacterium were tested for their susceptibilities to 22 antimi- crobial agents. All strains were susceptible to chloramphenicol, nalidixic acid, cotrimoxazole, tetracycline, netilmicin and norfloxacin; all were resistant to penicillin and ampicillin, and exhibited ß-lactamase activi- ty. However, there were significant differences

Z. González-Lama; S. Soria; A. Díez del Pino; M. T. Tejedor; P. Lupiola

12

IAC07-A4.2.04 QUANTIFYING PAST TRANSMISSIONS USING THE SAN MARINO SCALE  

Microsoft Academic Search

To date, at least five experiments which could be classified as Active SETI, or METI (Messaging to Extra-Terrestrial Intelligence) have been conducted from Planet Earth: the well-known Arecibo Message of 1974, two Cosmic Call transmissions from Evpatoria, the Teen-Age Message to the Stars also transmitted from Evpatoria, and the paradigm- altering Invitation to ETI, being quasi-transmitted continuously via the Internet.

13

EVIDENCIAS MORFOLÓGICAS EROSIVAS DE NIVELES MARINOS PLEISTOCENOS EN LA COSTA DEL JBEL MUSA (N. DE MARRUECOS)  

Microsoft Academic Search

The limestone rocky shore of Jbel Musa (North Morocco) shows erosive evidences of Pleistocene marine highstand (wave-cut platform, cliff, sea cave and notch). Several sets of staircased morphotectonic units (MTU) can be observed along the coast, like in the Rock of Gibraltar: +130-120 m, +90-80 m, +60-40 m y +25-0 m. The most recent coastal landforms are located in Perejil

J. Rodríguez Vidal; L. M. Cáceres Puro

14

EVALUACIÓN DEL EFECTO DEL VERTIDO TÓXICO SOBRE LA CALIDAD DEL AGUA Y LOS SEDIMENTOS DE LOS RÍOS AGRIO Y GUADIAMAR  

Microsoft Academic Search

The water and sediment quality of the Agrio and Guadiamar rivers has been studied for the 3 years after the Aznalcóllar mining accident. The environmental quality of the Guadiamar river upstream from the mine zone was good. However, it became very poor downstream from the mine, with high values of conductivity and metal concentrations, and low pH and alkalinity. In

J. Toja; E. Alcalá; G. Martín; C. Solà; M. Burgos; A. Plazuelo; N. Prat

15

Las aguas y sedimentos del rÌo tunecino Hamdoun presentan riesgo de disrupciÛn endocrina  

Microsoft Academic Search

were investigated in this study. The water and sediment samples were obtained from upstream and downstream outfalls of the Hamdoun River located in proximity of the industrial area in the centre region of Tunisia. Using an in vitro assay with bioluminescent cancer cells expressing luciferase gene under different hormonal responsive element control, we detected a much lower level of estrogenic

Mnif Wß; Pillon A; Duchesne MJ; Helal ANß; Nicolas JC; Balaguer P; Bartegi Aß

16

Distribución de parámetros texturales de los sedimentos superfi ciales en la Bahía de Chetumal: Implicaciones en la inferencia de transporte  

Microsoft Academic Search

The grain-size trend analysis (grain size, sorting and asymmetry) was determined from 43 stations to identify the path of sediment transport in the Chetumal Bay, Quintana Roo. The analysis of principal components and grain size trend analysis were applied to sediment textural parameters. It was established that better sorted sedimentary material is associated with stations with fi ne grain-size and

Alberto Sánchez; Teresa Álvarez-Legorreta; Ricardo Sáenz-Morales; Concepción Ortiz-Hernández; B. Estela López-Ortiz; Sergio Aguíñiga

2008-01-01

17

Efecto de la irradiación luminosa en la aclimatación de Mammillaria carmenae Castañeda (Cactaceae) proveniente de cultivo in vitro  

Microsoft Academic Search

Resumen Se reprodujo Mamillaria carmenae por cultivo in vitro a partir de areolas de una planta etiolada in vivo. Se obtuvieron plantas a partir de callos, las cuales se aclimatizaron bajo diferentes tratamientos de irradiación luminosa (50, 150 y 970 µmol m -2 s -1 ) bajo condiciones de invernadero. Durante la acli- matación se registraron la variación en el

Coca Soriano; Ortiz Montiel; Juan Gerardo; Sánchez Correa; Pérez Crisanto Joel

18

Toxicidad no específica en sedimentos portuarios, una aproximación al contenido de contaminantes críticos Non-specific toxicity in port sediments: an approach to the content of critical pollutants  

Microsoft Academic Search

Sediment quality was analyzed for total organic matter (TOM), polycyclic aromatic hydrocarbons (PAHs), trace metals (Cd, Pb, and Cu), and non-specific toxicity at four Chilean ports with different cabotage activities. TOM was analyzed by ignition, metals by polarography, PAHs by GC- MS, and non-specific toxicity with the fecundation technique (USEPA 1988). The ports at Iquique, San Vicente, and Talcahuano had

Gabriela Aguirre-Martínez; Anny Rudolph; Ramón Ahumada; Rodrigo Loyola; Valentina Medina

19

RESISTENCIA ANTIMICROBIANA EN BACTERIAS AISLADAS DE TILAPIAS, AGUA Y SEDIMENTO EN VENEZUELA Antimicrobial Resistance in Bacteria Isolated From Tilapia, Water and Sediment Samples In Venezuela  

Microsoft Academic Search

The indiscriminate use of antimicrobials exerts high selective pressure on bacteria, provoking the emergence and dissemination of genes resistance to them. Considering that in Lake Valencia great volumes of water drain as a consequence of intense anthropogenic activities, the bacterial resistance in feral and cultured tilapia was evaluated, and the inhibitory concentration of selected antimicrobials was determined. The sensitivity was

Julia D. Álvarez; Claudia P. Agurto; Ana M. Álvarez; José Obregón

2004-01-01

20

Analisis multielemental por activacion neutronica de sedimentos del Golfo de Ana Maria. (Multielemental analysis by neutron activation of sediments in the Ana Maria Gulf, Cuba).  

National Technical Information Service (NTIS)

In this paper general samples of marine sediments taken from six control stations of the Ana Maria Gulf (Cuba) were analyzed. For this purpose the thermal neutron activation analysis method was used. 18 elements were determinated. They are: Al, Ce, Co, Cs...

O. Diaz Rizo D. Gandarias R. Calzavilla G. Garcia

1990-01-01

21

RUNOFF AND SEDIMENT YIELDS SIMULATION UNDER FIVE SOIL MANAGEMENT PRACTICES SIMULACIÓN DE ESCURRIMIENTO Y SALIDA DE SEDIMENTOS EN CINCO PRÁCTICAS DE MANEJO DE SUELO  

Microsoft Academic Search

Runoff containing sediment, nutrients, and pesticides originating from agricultural uplands are the main pollution agents for the Lake of Pátzcuaro, Mich., México. The purpose of this research was to simulate runoff (Q) and sediment yield (Sy) under natural rainfall, through model simulation which describes hydrologic processes for five agricultural management systems in the Pátzcuaro region. Five treatments were imposed on

Mario Tapia-Vargas; Mario Tiscareño-Lopez; José L. Oropeza-Mota; Jeffry J. Stone; Miguel Velázquez-Valle

22

DISOLUCIÓN DE SÍLICE BIOGÉNICA EN SEDIMENTOS DE LAGOS UTILIZADOS COMO BIOINDICADORES DE CALIDAD DEL AGUA SILICA BIOGENIC DISSOLUTION IN SEDIMENT OF LAKES, LIKE OF WATER QUALITY BIOINDICATORS  

Microsoft Academic Search

The objective of this work is to show that the amorphous silica dissolution of biogenic origin (diatoms and phytolithes) is a bioindicator of quality of the water of lakes, validating itself with the determination of parameters physical- chemical. The determination of diatoms and phytolithes was made on sediment cores of the Chapala Lake, Mexico. The diatoms and phytolithes separated were

Isabel Israde

2007-01-01

23

Evaluación de la posible adulteración de mieles de abeja comerciales de origen costarricense al compararlas con mieles artesanales provenientes de apiarios específicos  

Microsoft Academic Search

SUMMARY. Evaluation of the potential adulteration of com- mercial honey distributed in Costa Rica compared with artesanian honey samples coming from specific apiaries. Honey is the principal apiculture product, produced by Apis mellifera bee. This, as any other food product, has to accomplish certain quality standards, including physicochemical, organoleptic and microbio- logical properties. Within these parameters, different measures are considered

Maurico Ureña Varela; Esteban Arrieta Bolaños; Eduardo Umaña; Luis Gabriel Zamora; María Laura Arias

2007-01-01

24

Contaminantes orgánicos persistentes en núcleos de sedimentos de la región sur de la Cuenca de las Californias Persistent organic pollutants in sediment cores from the southern region of the Bight of the Californias  

Microsoft Academic Search

In January 1998, four sediment cores were collected to reconstruct the history of contamination by persistent organic compounds in the southern region of the Bight of the Californias. Two groups of compounds were determined using chromatographic methods: petroleum hydrocarbons (aliphatic hydrocarbons, AHs, and polynuclear aromatic hydrocarbons, PAHs) and chlorinated hydrocarbons (pesticides and polychlorinated biphenyls, PCBs). The AHs had low concentrations,

D. I. Partida-Gutiérrez; J. A. Villaescusa

25

26 CFR 1.955-4 - Definition of less developed country.  

Code of Federal Regulations, 2013 CFR

... Liechtenstein Luxembourg Monaco Netherlands New Zealand Norway Union of South Africa San Marino Sweden Switzerland United Kingdom. (c) Termination of designation. Section 955(c)(3) provides that,...

2013-04-01

26

7 CFR 319.37-5 - Special foreign inspection and certification requirements.  

Code of Federal Regulations, 2013 CFR

...Sweden, Switzerland, Tajikistan, Tunisia, Turkmenistan, Ukraine, Uzbekistan, and Venezuela. (b)(1) Any of the...San Marino, Switzerland, Taiwan, Thailand, Tunisia, Ukraine, Uruguay, Venezuela, Yugoslavia; the...

2013-01-01

27

7 CFR 319.74-2 - Conditions governing the entry of cut flowers.  

Code of Federal Regulations, 2013 CFR

...New Zealand, Norway, Peru, Republic of South Africa, Russia, San Marino, Switzerland, Taiwan, Thailand, Tunisia, Ukraine, Uruguay, Venezuela, Yugoslavia; the European Union (Austria, Belgium, Bulgaria, Cyprus, Czech Republic,...

2013-01-01

28

THALLIUM IN THE MARINE ENVIRONMENT: FIRST ECOTOXICOLOGICAL ASSESSMENTS IN THE GUADALQUIVIR ESTUARY AND ITS POTENTIAL ADVERSE EFFECT ON THE DOÑANA EUROPEAN NATURAL RESERVE AFTER THE AZNALCÓLLAR MINING SPILL (SW SPAIN) TALIO EN EL MEDIO MARINO: PRIMERA VALORACIÓN ECOTOXICOLÓGICA EN EL ESTUARIO DEL GUADALQUIVIR Y SU EFECTO POTENCIAL ADVERSO EN LA RESERVA NATURAL DE DOÑANA DESPUÉS DEL VERTIDO MINERO DE AZNALCÓLLAR (SW DE ESPAÑA)  

Microsoft Academic Search

Thallium (Tl) is an extremely toxic but little-studied element in the marine environment and practically no information has been reported on the levels of Tl in marine organisms. After the Aznalcóllar mining spill (April 1998), high levels of metals were put into the environment. This acid- contaminated medium was responsible for the initial pollution effects measured in the Guadiamar River,

T. A. DelValls; V. Sáenz; A. M. Arias

1999-01-01

29

Biochemical characterization of the eelgrass Zostera marina at its southern distribution limit in the North Pacific [Caracterizacio??n bioqui??mica del pasto marino Zostera marina en el li??mite sur de su distribucio??n en el Paci??fico Norte  

USGS Publications Warehouse

The eelgrass Zostera marina L. is distributed along the Baja California Peninsula (Mexico) where it is exposed to a wide range of irradiances and temperatures that could promote changes in its biochemical composition. Consequently, the objective of this study was to characterize the variations in the levels of chlorophyll, carbohydrates, proteins, fiber, ash and calories in the shoots of Z. marina from the north (San Quintin) and south (Ojo de Liebre and San Ignacio lagoons) of the peninsula. Temperature in the southern lagoons was 5-6??C higher than in the northern lagoon; likewise, in situ irradiance was two-fold greater in the south than in the north. As a result of the lower irradiance levels, the concentration of chlorophyll in the shoots of Z. marina was twice as high (1.7 mg gWW-1) in the northern lagoon than in the southern ones (0.8 mg gWW-1). Similar to chlorophyll levels, the concentration of soluble carbohydrates in the shoots was greater in the northern lagoon than in the southern ones, suggesting that the high levels of chlorophyll are enough to compensate for the low irradiance levels and to maintain a positive carbon balance at San Quintin. On the other hand, the levels of proteins in the shoots from the north of the peninsula were slightly lower than those from the southern populations. In general, these results suggest that the different environmental conditions to which Z. marina is exposed along the peninsula impact its biochemical composition.

Cabello-Pasini, A.; Muniz-Salazar, R.; Ward, D. H.

2004-01-01

30

Use of digital multispectral videography to assess seagrass distribution in San Quinti??n Bay, Baja California, Mexico [Uso de videografi??a multiespectral digital para evaluar la distributio??n del pasto marino en Bahi??a San Quinti??n, Baja California, Me??xico  

USGS Publications Warehouse

Apparent threats to the spatial distribution of seagrass in San Quinti??n Bay prompted us to make a detailed assessment of habitats in the bay. Six coastal habitats and three seagrass subclasses were delineated using airborne digital multispectral videography (DMSV), Eelgrass, Zostera marina, was the predominant seagrass and covered 40% (1949 ha) of the areal extent of the bay in 1999. Eelgrass grew over a wide range of tidal depths from about -3.0 in mean lower low water (MLLW) to about 1.0 m MLLW, but greatest spatial extent occurred in intertidal areas -0.6 m to 1.0 m MLLW. Exposed-continuous (i.e., high density) eelgrass was the most abundant habitat in the bay. Widgeongrass, Ruppia maritima, was the only other seagrass present and covered 3% (136 ha) of the areal extent of the entire bay. Widgeongrass grew in single species stands in the upper intertidal (??? 0.4 MLLW) and intermixed with eelgrass at lower tidal depths. Overall accuracy of the six habitat classes and three subclasses in the DMSV map was relatively high at 84%. Our detailed map of San Quintin Bay can be used in future change detection analyses to monitor the health of seagrasses in the bay.

Ward, D. H.; Tibbitts, T. L.; Morton, A.; Carrera-Gonzalez, E.; Kempka, R.

2004-01-01

31

8 CFR 217.2 - Eligibility.  

Code of Federal Regulations, 2013 CFR

...Lithuania, Luxembourg, Malta, Monaco, the Netherlands, New Zealand, Norway, Portugal, Republic of Korea, San Marino...unrestricted right of permanent abode in the United Kingdom (England, Scotland, Wales, Northern Ireland, the Channel...

2013-01-01

32

15 CFR Supplement No. 3 to Part 744 - Countries Not Subject to Certain Nuclear End-Use Restrictions in § 744.2(a)  

Code of Federal Regulations, 2013 CFR

...End-Use Restrictions in § 744.2(a) Australia Austria Belgium Canada Denmark Finland France Germany Greece Iceland Ireland Italy (includes San Marino and Holy See) Japan Luxembourg Netherlands New Zealand Norway...

2013-01-01

33

76 FR 7225 - Center for Scientific Review; Notice of Closed Meetings  

Federal Register 2010, 2011, 2012, 2013

...evaluate grant applications. Place: InterContinental Mark Hopkins Hotel, 999 California Street, San Francisco, CA 94108...Island Avenue, NW., Washington, DC 20005. Contact Person: Michael A Marino, PhD, Scientific Review Officer, Center for...

2011-02-09

34

Upper and Lower-Extremity Motor Recovery After Traumatic Cervical Spinal Cord Injury: An Update From the National Spinal Cord Injury Database  

Microsoft Academic Search

Marino RJ, Burns S, Graves DE, Leiby BE, Kirshblum S, Lammertse DP. Upper- and lower-extremity motor recovery after traumatic cervical spinal cord injury: an update from the National Spinal Cord Injury Database.

Ralph J. Marino; Stephen Burns; Daniel E. Graves; Benjamin E. Leiby; Steven Kirshblum; Daniel P. Lammertse

2011-01-01

35

Evaluacion de treinta lineas mutantes de arroz (Oryza Sativa L.) provenientes de las variedades ICTA Virginia y Precozicta. (Field performance of thirty mutant lines of the rice (Oryza sativa L.) varieties ICTA-Virginia and Precoz-ICTA Jul 1993 - Jun 1994).  

National Technical Information Service (NTIS)

Fifteen mutant lines from the variety ICTA-Virginia and fifteen from the variety Precozicta were evaluated according to their agronomic characteristics under conditions of the Motagua river valley during 1992. The objective was to select genotypes showing...

R. Montepeque L. Molina J. Lopez W. Pazos J. Ramirez

1994-01-01

36

Concepts & Procedures. [SITE 2002 Section].  

ERIC Educational Resources Information Center

|This document contains the following full and short papers on concepts and procedures from the SITE (Society for Information Technology & Teacher Education) 2002 conference: "Exploring Minds Network" (Marino C. Alvarez and others); "Learning Communities: A Kaleidoscope of Ecological Designs" (Alain Breuleux and others); "PDA's and Research: A…

Sarner, Ronald, Ed.; Mullick, Rosemary J., Ed.; Bauder, Deborah Y., Ed.

37

Dolphin-Assisted Therapy: More Flawed Data and More Flawed Conclusions  

Microsoft Academic Search

Dolphin-Assisted Therapy (DAT) is an increasingly popular choice of treatment for illness and developmental disabilities by providing participants with the opportunity to swim or interact with live captive dolphins. Two reviews of DAT (Marino and Lilienfeld (1998) and Humphries (2003)) concluded that there is no credible scientific evidence for the effectiveness of this intervention. In this paper, we offer an

Lori Marino; Scott O. Lilienfeld

2007-01-01

38

Why Should Community College Faculty Write Grant Proposals?  

Microsoft Academic Search

Community colleges have seen dramatic enrollment increases (Kasper, 2002), and some are now offering 4-year degrees (Evelyn, 2003). They are eligible for more grants than in the past, and community college funding from state and federal appropriations is shrinking (Lawrence & Marino, 2003). For these reasons, it is imperative that community college faculty become involved in grant proposal preparation and

Phyl Renninger; Anne Meilof; Todd Pitts; Janie K. Smalley

2007-01-01

39

Revised assessment of cancer risk to dichloromethane II. Application of probabilistic methods to cancer risk determinations  

Microsoft Academic Search

An updated PBPK model of methylene chloride (DCM, dichloromethane) carcinogenicity in mice was recently published using Bayesian statistical methods (Marino et al., 2006). In this work, this model was applied to humans, as recommended by Sweeney et al. (2004). Physiological parameters for input into the MCMC analysis were selected from multiple sources reflecting, in each case, the source that was

Raymond M. David; Harvey J. Clewell; P. Robinan Gentry; Tammie R. Covington; David A. Morgott; Dale J. Marino

2006-01-01

40

Essentialism Revisited: Evolutionary Theory and the Concept of Mental Disorder  

Microsoft Academic Search

J. C. Wakefield's (1999) elaboration of his harmful dysfunction analysis (HDA) of mental disorder does little to address previous criticisms (S. O. Lilienfeld & L. Marino, 1995) and instead reveals further conceptual weaknesses in his position. The authors demonstrate that (a) a Roschian analysis can account for the results of all of Wakefield's conceptual experiments and predicts a number of

Scott O. Lilienfeld; Lori Marino

1999-01-01

41

3. Historic American Buildings Survey, John Andre, November 15, 1777, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey, John Andre, November 15, 1777, Henry E. Huntington Library, San Marino, California, See Catalog of Graphic Material #44, PHOTOCOPY OF 'MUD ISLAND WITH THE OPERATIONS FOR REDUCING IT'. - Fort Mifflin, Mud Island, Marine & Penrose Ferry Roads, Philadelphia, Philadelphia County, PA

42

Care and Feeding of the Library Researcher.  

ERIC Educational Resources Information Center

|Describes the patrons of and typical research projects conducted at the Huntington Library in San Marino, California, as well as the role of the library, including research services and grants, library collections, and assistance to researchers beyond the library setting. (CLB)|

Woodward, Daniel

1987-01-01

43

The effects of the adequacy of general education teachers on special needs students in inclusive classrooms  

Microsoft Academic Search

Problem. Many general education teachers have not had the professional training and specific coursework to teach students with special needs (Monohan, Marino & Miller, 1996). Currently, teacher preparation programs differ from general educators and special educators; there are two distinct tracks. ^ This study investigated the effects that teacher attitude and training have on the academic achievement of included special

Lisa C Currie

2005-01-01

44

Beautiful Science: Worth a Visit  

ERIC Educational Resources Information Center

|For those in the profession of teaching physics who reside in or plan to visit the Los Angeles area, I would highly recommend a trip to the Huntington Library in San Marino, specifically to a permanent exhibit entitled "Beautiful Science: Ideas that Changed the World" in the Dibner Hall of the History of Science. The exhibit contains original…

Bingham, Frederick M.

2013-01-01

45

Desarrollo y utilización de habilidades: el caso de los migrantes en León, Guanajuato, procedentes de la Ciudad de México  

Microsoft Academic Search

En este artículo se presenta una investigación sobre el desarrollo y el uso de habilidades de los migrantes provenientes de la Ciudad de México que radican en León, Guanajua- to. Los datos del Censo General de Población y Vivienda 2000 relativos a los habitantes de León revelan que los migrantes provenientes de los grandes centros urbanos tienen, en promedio, mayores

Ricardo Sabatés Aysa

46

Avaliação da aplicação de fungicida às sementes de amendoim antes do envelhecimento acelerado  

Microsoft Academic Search

4 RESUMO - Os objetivos do trabalho foram os de avaliar o efeito da aplicação de fungicida às sementes de amendoim (Arachis hypogaea L.), que foram colhidas em distintos estádios de maturação e provenientes de plantas-mãe que foram ou não submetidas à calagem, nas condições de envelhecimento acelerado. Foram avaliados quatro lotes de sementes do cultivar Botucatu, provenientes das áreas

Claudia A. V. Rossetto; Antonio E. S. Araújo; Tatiana M. Lima

2003-01-01

47

Identifying coseismic subsidence in tidal-wetland stratigraphic sequences at the Cascadia subduction zone of western North America  

Microsoft Academic Search

Tidal-wetland stratigraphy reveals that great plate boundary earthquakes have caused hundreds of kilometers of coast to subside at the Cascadia subduction zone. However, determining earthquake recurrence intervals and mapping the coastal extent of past great earthquake ruptures in this region are complicated by the effects of many sedimento!ogic, hydrographic, and oceanographic processes that occur on the coasts of tectonically passive

Alan R. Nelson; Ian Shennan; Antony J. Long

1996-01-01

48

Cambios vegetales holocenos en la región mediterránea de la Península Ibérica: ensayo de síntesis  

Microsoft Academic Search

La Palinolog ía se ha revelado como una de las disciplinas más útiles para la reconstrucción de los paisajes vegetales del pasado. En la Península Ibérica, durante la última década se ha producido un número elevado de secuencias polínicas, obtenidas a partir de sedimentos naturales, que además disponen de un número suficiente de dataciones absolutas, hecho que permite encuadrar en

S. Riera Mora

49

Vegetais fósseis do Terciário brasileiro  

Microsoft Academic Search

A bacia de Fonseca, situada na região do Quadrilátero Ferrífero, no estado de Minas Gerais, sudeste do Brasil, constitui um clássico exemplo de sedimentos terciários, tendo despertado o interesse de vários pesquisadores, desde a segunda metade do século passado, por conter depósitos de \\

Claudio Limeira Mello; Lílian Paglarelli Bergqvist; Lucy Gomes Sant

50

Submillimeter life positions of bacteria, protists, and metazoans in laminated sediments of the Santa Barbara Basin  

Microsoft Academic Search

To provide insights into the biogeochemistry of environments where steep chemical gradients place anaerobes, microaerophiles, and aerobes in close proximity, it might be necessary to survey biotic distributions on scales that are not possible using conventional ecological approaches. To overcome such limitations, we adapted sedimento- logical and cell biological methods to examine the life positions of microbes within sediments. This

Joan M. Bernhard; Pieter T. Visscher; Samuel S. Bowser

2003-01-01

51

Stability Conditions For Topological D-branes: A Worldsheet Approach  

Microsoft Academic Search

We study conditions on the topological D-branes of types A and B obtained by requiring a proper matching of the spectral flow operators on the boundary. These conditions ensure space-time supersymmetry and stability of D-branes. In most cases, we reproduce the results of Marino-Minasian-Moore-Strominger, who studied the same problem using the supersymmetric Born-Infeld action. In some other cases, corresponding to

Anton Kapustin; Yi Li

2003-01-01

52

The Chemistry of Coffee  

NSDL National Science Digital Library

The paper Our Everyday Cup of Coffee: The Chemistry behind Its Magic by Marino Petracco provides a hearty blend of molecules for this month. The author deals with coffee at a number of different levels ranging from the economic and social to the still perplexing questions of flavor and aroma. The associated molecules demonstrate a range of structural features that students will benefit from examining in three dimensions.

53

Virasoro constraints for Kontsevich-Hurwitz partition function  

Microsoft Academic Search

In [1, 2] M.Kazarian and S.Lando found a 1-parametric interpolation between Kontsevich and Hurwitz partition functions, which entirely lies within the space of KP tau-functions. In [3] V.Bouchard and M.Marino suggested that this interpolation satisfies some deformed Virasoro constraints. However, they described the constraints in a somewhat sophisticated form of AMM-Eynard equations [4-7] for the rather involved Lambert spectral curve.

A. Mironov; A. Morozov

2009-01-01

54

New books in review  

Microsoft Academic Search

12 AMERICANS SPEAK. Facsimiles of Original Editions selected and annotated by John E. Pomfret. San Marino, Calif: Hunting?ton Library, 1954; pp. vi+183. $5.00.AMERICAN DEMAGOGUES: TWENTIETH CENTURY. By Reinhard H. Luthin. Boston: The Beacon Press, 1954; pp. xv+368. $5.00,ADVENTURES IN POLITICS: WE GO TO THE LEGISLATURE. By Richard L. Neuberger. New York: Oxford University Press, 1954; pp. 203. $3.50.CIVILIZATION AND THE

Wilbur Samuel Howell; Barnet Baskerville; Robert D. Clark; James J. Murphy; Guy A. Cardwell; Jonathan Curvin; Russell W. Lembke; Harold Ehrensperger; E. J. West; Albert E. Johnson; Fairfax Proudfit Walkup; John T. Dugan; Edwin Duerr; Claude L. Shaver; Harold P. Zelko; Harold F. Harding; John Robson; Roy F. Hudson; Paul C. Boomsliter; R. S. Brubaker; John Keltner; Elwood Murray; John P. Highlander; Willard Bellman; E. Winston Jones

1955-01-01

55

Periglacial landscape evolution and environmental changes of Arctic lowland areas for the last 60000 years (western Laptev Sea coast, Cape Mamontov Klyk)  

Microsoft Academic Search

Non-glaciated Arctic lowlands in north-east Siberia were subjected to extensive landscape and environmental changes during the Late Quaternary. Coastal cliffs along the Arctic shelf seas expose terrestrial archives containing numerous palaeoenvironmental indicators (e.g., pollen, plant macro-fossils and mammal fossils) preserved in the permafrost. The presented sedimento- logical (grain size, magnetic susceptibility and biogeochemical parameters), cryolithological, geochronological (radiocarbon, accelerator mass spectrometry

Lutz Schirrmeister; Guido Grosse; Viktor Kunitsky; Diana Magens; Hanno Meyer; Alexander Dereviagin; Tatyana Kuznetsova; Andrei Andreev; Olga Babiy; Frank Kienast; Mikhael Grigoriev; Pier Paul Overduin; Frank Preusser

2008-01-01

56

Beautiful Science: Worth a Visit  

NASA Astrophysics Data System (ADS)

For those in the profession of teaching physics who reside in or plan to visit the Los Angeles area, I would highly recommend a trip to the Huntington Library in San Marino, specifically to a permanent exhibit entitled ``Beautiful Science: Ideas that Changed the World'' in the Dibner Hall of the History of Science. The exhibit contains original books and manuscripts from the library's own collections. The sheer magnitude of human achievement represented here and the amount of effort and money that must have been required to amass these books boggles the mind.

Bingham, Frederick M.

2013-03-01

57

CARACTERÍSTICAS, OPERACIONALIDADE E PRODUÇÃO DA FROTA SERREIRA NO MUNICÍPIO DA RAPOSA - MA  

Microsoft Academic Search

Este trabalho aborda as características, operacionalidade e produção pesqueira da frota serreira, no município da Raposa, no período de março a dezembro de 2003, com desembarques nos portos da Praia da Raposa e Braga. Os dados utilizados são provenientes da Capitania dos Portos do Maranhão, Progra- ma Revizee (Recursos Vivos da Zona Econômica exclusiva) e da comunidade de pescadores do

Elizabeth Galvão Soares; Milton Gonçalves da Silva Júnior

58

Efeitos da monensina sobre a fermentação e sensibilidade de bactérias ruminais de bovinos sob dietas ricas em volumoso ou concentrado  

Microsoft Academic Search

RESUMO - Objetivou-se avaliar os efeitos da monensina sobre as mudanças nos padrões de fermentação e resistência à perda do potássio intracelular das bactérias ruminais provenientes de quatro bovinos recebendo dietas ricas em volumoso ou concentrado. As bactérias obtidas por centrifugação diferencial foram resuspensas em um meio pobre em potássio, no qual foi medida a perda do p otássio intracelular,

Rogério de Paula Lana; James B. Russell

2001-01-01

59

Peer review of RELAP5/MOD3 documentation  

SciTech Connect

A peer review was performed on a portion of the documentation of the RELAP5/MOD3 computer code. The review was performed in two phases. The first phase was a review of Volume 3, Developmental Assessment problems, and Volume 4, Models and Correlations. The reviewers for this phase were Dr. Peter Griffith, Dr. Yassin Hassan, Dr. Gerald S. Lellouche, Dr. Marino di Marzo and Mr. Mark Wendel. The reviewers recommended a number of improvements, including using a frozen version of the code for assessment guided by a validation plan, better justification for flow regime maps and extension of models beyond their data base. The second phase was a review of Volume 6, Quality Assurance of Numerical Techniques in RELAP5/MOD3. The reviewers for the second phase were Mr. Mark Wendel and Dr. Paul T. Williams. Recommendations included correction of numerous grammatical and typographical errors and better justification for the use of Lax`s Equivalence Theorem.

Craddick, W.G.

1993-12-31

60

210Po Log-normal distribution in human urines: survey from central Italy people.  

PubMed

The death in London of the former secret service agent Alexander Livtinenko on 23 November 2006 generally attracted the attention of the public to the rather unknown radionuclide (210)Po. This paper presents the results of a monitoring programme of (210)Po background levels in the urines of noncontaminated people living in Central Italy (near the Republic of S. Marino). The relationship between age, sex, years of smoking, number of cigarettes per day, and (210)Po concentration was also studied. The results indicated that the urinary (210)Po concentration follows a surprisingly perfect Log-normal distribution. Log (210)Po concentrations were positively correlated to age (p < 0.0001), number of daily smoked cigarettes (p = 0.006), and years of smoking (p = 0.021), and associated to sex (p = 0.019). Consequently, this study provides upper reference limits for each sub-group identified by significantly predictive variables. PMID:19750019

Sisti, D; Rocchi, M B L; Meli, M A; Desideri, D

2009-03-01

61

210Po determination in urines of people living in Central Italy.  

PubMed

This paper presents the results of the monitoring programme on the urines of people living in an area of Central Italy (near the Republic of S. Marino) to evaluate the background level of the 210Po excretion rate (mBq day(-1)) in this region. The volunteers were subdivided in five age classes and in every age class groups of males and females, cigarette smokers and non-smokers were taken into account. The results indicated that the 210Po excretion rate was widely distributed within each group of volunteers. The 210Po excretion rate was <30 mBq day(-1) for 93.2% of people. The obtained results are discussed and some conclusion, based upon the average values, was drawn. PMID:19081163

Meli, M A; Desideri, D; Roselli, C; Feduzi, L

2008-12-09

62

Prevalencia de deficiencia subclínica de vitamina A y desnutrición en niños marginales de Maracaibo - Venezuela  

Microsoft Academic Search

RESUMEN. El presente estudio fue realizado para estimar la prevalencia de deficiencia de vitamina A en niños, mediante examen clínico, oftalmológico y por citología de impresión conjuntival (CIC); y el estado nutricional, analizando los indicadores antropométricos T\\/\\/E, P\\/\\/E y P\\/\\/T. La población de estudio incluyó 157 niños, 2-6 años de edad, provenientes de barrios marginales urbanos y rurales de Maracaibo,

Haydée V. Castejón; Pablo Ortega; María E. Díaz; Daisy Amaya; Gisela Gómez; María Ramos; María V. Alvarado; Jesús R. Urrieta

63

Buriti (Mauritia vinifera Martius) pulp  

Microsoft Academic Search

RESUMO: Este trabalho trata da avaliação das propriedades da polpa celulósica obtida a partir das palhas provenientes das folhas da palmácea Mauritia vinifera Martius pelo processo kraft, tendo em vista, a sua utilização como matéria-prima alternativa na produção de papel. O álcali ativo foi conduzido em teores de 8,32 a 11,68%; a temperatura máxima variou de 157 a 174 °C;

Sanatiel de Jesus Pereira; Moacir Kaminski; Umberto Klock; Fernando José Fabrowski

64

Celulose de tucum (Bactris inundata Martius) Tucum pulp (Bactris inundata Martius)  

Microsoft Academic Search

RESUMO: Este trabalho trata da avaliação das propriedades da polpa celulósica obtida a partir das palhas provenientes das folhas da palmácea Bactris inundata Martius pelo proc- esso Kraft, tendo em vista a sua utilização como matéria-prima alternativa na produção de papel. O álcali ativo foi conduzido em teores de 8,32 a 11,68%; a temperatura máxima variou de 157 a 174

Sanatiel de Jesus Pereira; Moacir Kaminski; Umberto Klock; Fernando José Fabrowski

65

Carbohydrates as indicators of biogeochemical processes  

NASA Astrophysics Data System (ADS)

A method is presented to study the carbohydrate composition of marine objects involved into sedimento- and diagenesis (plankton, particulate matter, benthos, and bottom sediments). The analysis of the carbohydrates is based upon the consecutive separation of their fractions with different solvents (water, alkali, and acid). The ratio of the carbohydrate fractions allows one to evaluate the lability of the carbohydrate complex. It is also usable as an indicator of the biogeochemical processes in the ocean, as well of the genesis and the degree of conversion of organic matter in the bottom sediments and nodules. The similarity in the monosaccharide composition is shown for dissolved organic matter and aqueous and alkaline fractions of seston and particulate matter.

Lazareva, E. V.; Romankevich, E. A.

2012-05-01

66

Compression-triggered instabilities of multi-layer systems: From thin elastic membranes to lipid bilayers on flexible substrates  

NASA Astrophysics Data System (ADS)

Instabilities are triggered when elastic materials are subjected to compression. We explore new features of two distinct systems of this type. First, we describe a two-layer polymeric system under biaxial compressive stress, which exhibits a repetitive wrinkle-to-fold transition that subsequently generates a hierarchical network of folds during reorganization of the stress field. The folds delineate individual domains, and each domain subdivides into smaller ones over multiple generations. By modifying the boundary conditions and geometry, we demonstrate control over the final network morphology. Some analogies to the venation pattern of leaves are indicated. Second, motivated by the confined configurations common to cells, which are wrapped in lipid bilayer membranes, we study a lipid bilayer, coupled to an elastic sheet, and demonstrate that, upon straining, the confined lipid membrane is able to passively regulate its area. In particular, by stretching the elastic support, the bilayer laterally expands without rupture by fusing adhered lipid vesicles; upon compression, lipid tubes grow out of the membrane plane, thus reducing its area. These transformations are reversible, as we show using cycles of expansion and compression, and closely reproduce membrane processes found in cells during area regulation. The two distinct systems illustrate the influence of the substrate on finite amplitude shape changes, for which we describe the time-dependent shape evolution as the stress relaxes. This talk describes joint research with Manouk Abkarian, Marino Arroyo, Pilnam Kim, Mohammad Rahimi and Margarita Staykova.

Stone, Howard A.

2013-03-01

67

Cerebellum: Development and Medulloblastoma  

PubMed Central

In the last 20 years, it has become clear that developmental genes and their regulators, noncoding RNAs including microRNAs and long-noncoding RNAs, within signaling pathways play a critical role in the pathogenesis of cancer. Many of these pathways were first identified in genetic screens in Drosophila and other lower organisms. Mammalian orthologs were subsequently identified and genes within the pathways cloned and found to regulate cell growth. The GENES and pathways expressed during embryonic development, including the Notch, Wnt/?-Catenin, TGF-?/BMP, Shh/Patched, and Hippo pathways are mutated, lost, or aberrantly regulated in a wide variety of human cancers, including skin, breast, blood, and brain cancers, including medulloblastoma. These biochemical pathways affect cell fate determination, axis formation, and patterning during development and regulate tissue homeostasis and regeneration in adults. Medulloblastoma, the most common malignant nervous system tumor in childhood, are thought to arise from disruptions in cerebellar development [reviewed by Marino, S. (2005). Medulloblastoma: Developmental mechanisms out of control. Trends Mol. Med. 11, 17–22]. Defining the extracellular cues and intracellular signaling pathways that control cerebellar neurogenesis, especially granule cell progenitor (GCP) proliferation and differentiation has been useful for developing models to unravel the mechanisms underlying medulloblastoma formation and growth. In this chapter, we will review the development of the cerebellar cortex, highlighting signaling pathways of potential relevance to tumorigenesis.

Roussel, Martine F.; Hatten, Mary E.

2011-01-01

68

Experimental studies of the direct flexoelectric effect in bone materials  

NASA Astrophysics Data System (ADS)

The piezoelectric effect in biological tissues has been attracting research interest due to the hypothesis that it may behave as a biological transducer, which can convert external stimuli into biologically-recognizable signals capable of controlling growth or resorptive processes. The piezoelectric effect in dried bone materials was first observed in 1957 [1]. A link between the effect and the adaptive response of bone cells was proposed in 1970 [2]. In this paper, we report our recent measurements on the direct flexoelectric effect in bone materials. Our specimens are both dried and wet bones. The origin of both piezoelectricity and flexoelectricity in bone may be ascribed to the crystalline alignment of the micelle of collagen molecules. The Curie group symmetries of the configuration of collagen fibres in the bone texture demonstrate the existence of both effects. However, our experimental results show that the piezoelectric responses in bone materials may be dominated by flexoelectricity at the micro and nano scales. Finally, we propose a link between the flexoelectric effect and bone spur (osteophyte). [1] E. Fukada and I. Yasuda, J. Phys. Soc. Jpn. 12, 1158 (1957). [2] A. Marino and R. Becker, Nature 228, 78 (1970).

Fu, John

2010-03-01

69

The Telescope: Outline of a Poetic History  

NASA Astrophysics Data System (ADS)

Amongst the first editions of Galileo's books, only the Saggiatore has on its frontispiece the image of the telescope. Indeed, the telescope is not pictured on the very emphatic frontispieces of the other books in which Galileo was presenting and defending the results achieved by his celestial observations, such as the Sidereus Nuncius. Many contemporary scientists denied the reliability of the telescope, and some even refused to look into the eyepiece. In the 16th and 17th century, the lenses, mirrors, and optical devices of extraordinary complexity did not have the main task of leading to the objective truth but obtaining the deformation of the reality by means of amazing effects of illusion. The Baroque art and literature had the aim of surprising, and the artists gave an enthusiastic support to the telescope. The poems in praise of Galileo's telescopic findings were quite numerous, including Adone composed by Giovanni Battista Marino, one of the most renowned poets of the time. The Galilean discoveries were actually accepted by the poets as ideologically neutral contributions to the "wonder" in spite they were rejected or even condemned by the scientists, philosophers, and theologians.

Stocchi, M. P.

2011-06-01

70

Neoproterozoic ice sheets of the Siberian Platform: U-Pb-LA-ICP-MS ages of detrital zircons from the Bol'shoi Patom formation and the geotectonic position of its provenance  

NASA Astrophysics Data System (ADS)

The centers of many Neoproterozoic and Phanerozoic glaciations were located on cratons and crystalline shields not necessarily, as some researchers believe, associated with rifts. An example is the Vendian Bol'shoi Patom glacial formation (Lena River, Yakutia). The U-Pb ages of detrital zircons from this formation imply that it was deposited by glaciers located on the pre-Riphean crystalline shields of the Siberian Platform. Glaciation in this region occurred after cessation of rifting and could not be related to the latter. The Bol'shoi Patom Formation is an element of the Middle Siberian glacial horizon that was deposited during the Marino Glaciation and is traceable along the southern periphery of the Siberian Platform from the Aldan Shield to the Baikal and Sayany regions. This indicates that the Marinoan Glaciation in Siberia involved at least the entire southern part of the Siberian Platform. Rifting was not the single, or even a principal, factor responsible for glaciations, although it could accompany and enhance them simultaneously providing space for sedimentation and conditions for preserving glacial deposits from erosion.

Chumakov, N. M.; Linnemann, U.; Hofmann, M.; Pokrovskii, B. G.

2011-12-01

71

Effects of the 1991-92 El Niño on scleractinian corals of the Costa Rican central Pacific coast.  

PubMed

Coral communities on the central Pacific coast of Costa Rica were affected during the 1991-92 El Niño warming event. More than 57% of all observed colonies at three localities (Parque Nacional Manuel Antonio, Punta Cambutal, and Parque Marino Ballena) were bleached. Mortality during this El Niño was much lower (approximately 9%) than in previous events. Psammocora spp. accounted for approximately 66% of dead corals, while massive (Porites lobota, Pavona spp.) and branching (Pocillopora spp.) for approximately 34%. Our results suggest that the observed bleaching in P. lobata was related to zooxanthellar densities and not to changes in pigment concentrations: only chlorophyll a varied between normally pigmented and bleached colonies at one locality (Ballena). Site differences in zooxanthellar densities or their pigment concentrations, may not be the result of the bleaching event itself, because a percentage of dead corals and zooxanthellar densities of bleached colonies seems to follow a trend with the exposure to tidal regimes and currents at each site. Local oceanographic conditions can be influencing the zooxanthellar densities and their response to the warming, together with intrinsic differences between colonies as well. The impact of this event can be considered serious given the short period of time that elapsed between El Niño related mortalities and the slow reefs recovery, the mode of reproduction of reef building species, and the anthropogenic-originated disturbances which affect the coral communities and reefs of the Costa Rican central Pacific coast. PMID:15264538

Jiménez, C; Cortés, J

2001-12-01

72

Modelos Teoricos de Linhas de Recombinacao EM Radio Frequencias Para Regioes H II  

NASA Astrophysics Data System (ADS)

Foram feitos modelos de linhas de recombinção provenientes de regiões HII nas frequências de rádio para distintos números quãnticos. Estes modelos consideram regrões H II esfericamente simétricas com variações radiais na densidade e temperatura eletrônica, efeitos de colisoes inelásticas dos eletrons (alargarnento por pressão), e afastarnento do equiliíbrio termodinâmico local. 0 bojetivo é construir o perfil da linha para cada ponto da nuvern e obter o valor médio resultante da sua convoluçã com o feixe da antena de tarnanho comparável corn o tarnanho angular da nuvern para posterIor cornpara o corn

Abraham, Z.; Cancoro, A. C. O.

1987-05-01

73

Marine hydrogeology: recent accomplishments and future opportunities  

NASA Astrophysics Data System (ADS)

Marine hydrogeology is a broad-ranging scientific discipline involving the exploration of fluid-rock interactions below the seafloor. Studies have been conducted at seafloor spreading centers, mid-plate locations, and in plate- and continental-margin environments. Although many seafloor locations are remote, there are aspects of marine systems that make them uniquely suited for hydrologic analysis. Newly developed tools and techniques, and the establishment of several multidisciplinary programs for oceanographic exploration, have helped to push marine hydrogeology forward over the last several decades. Most marine hydrogeologic work has focused on measurement or estimation of hydrogeologic properties within the shallow subsurface, but additional work has emphasized measurements of local and global fluxes, fluid source and sink terms, and quantitative links between hydrogeologic, chemical, tectonic, biological, and geophysical processes. In addition to summarizing selected results from a small number of case studies, this paper includes a description of several new experiments and programs that will provide outstanding opportunities to address fundamental hydrogeologic questions within the seafloor during the next 20-30 years. L'hydrogéologie marine est une large discipline scientifique impliquant l' exploration des interactions entre les fluides et les roches sous les fonds marins. Des études ont été menées dans les différents environnements sous-marins (zone abyssale, plaque océanique, marges continentales). Bien que de nombreux fonds marins soient connus, il existe des aspects des systèmes marins qui les rendent inadaptés à l'analyse hydrologique. De nouveaux outils et techniques, et la mise en oeuvre de nombreux programmes multidisciplinaires d'exploration océanographique, ont aidé à pousser en avant l'hydrogéologie marine ces dix dernières années. La plus part des études hydrogéologiques se sont concentrées jusqu'à présent sur la mesure ou l'estimation des propriétés à la sub-surface des fonds marins, et des travaux complémentaires ont mis en valeur les mesures de flux, local ou global, de termes « sources » et « pertes », et des liens quantitatifs entre l'hydrogéologie, la chimie, la tectonique, la biologie, et les processus géophysiques. Cet article vise à résumer des résultats sélectionnés parmi un petit nombre d'études, et à décrire plusieurs nouvelles expériences et programmes, qui sont autant d'opportunités pour répondre aux questions fondamentales relatives aux fonds marins, posées ces dernières 20-30 années. La hidrogeología marina es una disciplina científica de amplios alcances que involucra la exploración de interacciones fluido-roca por debajo del fondo del mar. Se han llevado a cabo estudios en centros de expansión del fondo del mar, lugares en medio de una placa, y en ambientes de placa y margen continental. Aunque muchos sitios en el fondo del mar son remotos, existen aspectos de estos sistemas marinos que los hacen particularmente adaptables para análisis hidrológico. Nuevas técnicas y herramientas desarrolladas, y el establecimiento de varios programas multidisciplinarios para exploración oceanográfica, han ayudado a impulsar la hidrogeología marina hacia delante durante las ultimas décadas. La mayor parte del trabajo hidrogeológico marino se ha enfocado en la medición o estimación de propiedades hidrogeológicas dentro del subsuelo superficial, pero trabajo adicionalha enfatizado mediciones de flujos globales y locales, términos de fuente y sumidero de fluidos, y vínculos cuantitativos entre procesos hidrogeológicos, químicos, tectónicos, biológicos y geofísicos. Además de resumir resultados seleccionados de un número pequeño de estudios de caso, este artículo incluye una descripción de varios programas y experimentos nuevos que aportarán oportunidades excepcionales para dirigir preguntas hidrogeológicas fundamentales dentro del fondo oceánico durante los siguientes 20-30 años.

Fisher, A. T.

2005-03-01

74

Vitamin D, Race, and Excessive Daytime Sleepiness  

PubMed Central

Study Objectives: First, to determine whether serum vitamin D levels were correlated with excessive daytime sleepiness (EDS) in patients with or without vitamin D deficiency (VitDd). Second, to assess whether race affected the relation between vitamin D levels and EDS. Methods: Serum 25-hydroxyvitamin D (25OHD) was measured by immunoassay in a consecutive series of 81 sleep clinic patients who complained of sleep problems and nonspecific pain (25OHD < 20 ng/mL ' VitDd). Sleepiness was determined using the Epworth Sleepiness Scale score ([ESSs] ESSs ? 10 ' EDS). Correlations were assessed using Pearson r. Results: In patients without VitDd (25OHD ? 20 ng/mL), ESSs was inversely correlated with vitamin D concentration (r = 0.45, p < 0.05). The group consisted of 6% black patients, compared with 35% for the entire cohort. Among the patients who had VitDd (25OHD < 20 ng/mL), ESSs was directly correlated with 25OHD in black (r = 0.48, p < 0.05) but not white patients. In black patients, mean ESSs in patients with VitDd were higher and 25OHD levels were lower p < 0.05). Conclusions: The results suggested the novel possibility that VitDd-related disease has a yet-to-be-identified mechanistic role in the presentation of sleepiness, sleep disorders, or both. Further research is needed to clarify the mechanism(s) involved in producing the complex relationships noted. Commentary: A commentary on this article appears in this issue on page 699. Citation: McCarty DE; Reddy A; Keigley Q; Kim PY; Marino AA. Vitamin D, race, and excessive daytime sleepiness. J Clin Sleep Med 2012;8(6):693-697.

McCarty, David E.; Reddy, Aronkumar; Keigley, Quinton; Kim, Paul Y.; Marino, Andrew A.

2012-01-01

75

The game of active search for extra-terrestrial intelligence: breaking the `Great Silence'  

NASA Astrophysics Data System (ADS)

The search for extra-terrestrial intelligence (SETI) has been performed principally as a one-way survey, listening of radio frequencies across the Milky Way and other galaxies. However, scientists have engaged in an active messaging only rarely. This suggests the simple rationale that if other civilizations exist and take a similar approach to ours, namely listening but not broadcasting, the result is a silent universe. A simple game theoretical model, the prisoner's dilemma, explains this situation: each player (civilization) can passively search (defect), or actively search and broadcast (cooperate). In order to maximize the payoff (or, equivalently, minimize the risks) the best strategy is not to broadcast. In fact, the active search has been opposed on the basis that it might be dangerous to expose ourselves. However, most of these ideas have not been based on objective arguments, and ignore accounting of the possible gains and losses. Thus, the question stands: should we perform an active search? I develop a game-theoretical framework where civilizations can be of different types, and explicitly apply it to a situation where societies are either interested in establishing a two-way communication or belligerent and in urge to exploit ours. The framework gives a quantitative solution (a mixed-strategy), which is how frequent we should perform the active SETI. This frequency is roughly proportional to the inverse of the risk, and can be extremely small. However, given the immense amount of stars being scanned, it supports active SETI. The model is compared with simulations, and the possible actions are evaluated through the San Marino scale, measuring the risks of messaging.

de Vladar, Harold P.

2013-01-01

76

Polvo en la Región de los Troyanos  

NASA Astrophysics Data System (ADS)

La posible existencia de un anillo de polvo en la resonancia 1:1 con Júpiter formado por partículas provenientes de colisiones de asteroides fue propuesta por Liou and Zook (Icarus 113, 403, 1995) y estudiada extensamente por Vieira Martins and Gomes (VIII Reunión Regional Latinoamericana de Astronomía, Montevideo,1995). Si bien las partículas quedarían atrapadas sólo por períodos de algunos miles de años, el proceso colisional continuo en el cinturón de asteroides mantendría constante la densidad, presentándose una mayor concentración en la región de los troyanos. En el presente trabajo se presentan resultados preliminares sobre observaciones polarimétricas realizadas desde CASLEO de la región de L5 que confirmarían la existencia y variaciones de densidad en el anillo de polvo.

Gilhutton, R.; Brunini, A.; Coldwell, G.

77

Um supressor de fundo térmico para a câmara infravermelha CamIV  

NASA Astrophysics Data System (ADS)

O ângulo sólido subtendido pelos pixels na câmara infravermelha do NexGal (CamIV) que operamos no OPD/LNA contém contribuições provenientes do sistema de coleta de fluxo propriamente dito - sendo esta a parte que interessa para as medidas astronômicas - e contribuições da obstrução central, sistema de suporte do espelho secundário e região exterior à pupila de entrada do telescópio. Estas últimas contribuições são devi-das à emissão de corpo negro à temperatura ambiente e aumentam exponencialmente para comprimentos de onda maiores que 2 micra (banda K, no infravermelho próximo). Embora a resultante pode ser quantificada e subtraída dos sinais relevantes, sua variância se adiciona à variância do sinal, e pode ser facilmente a contribuição domi-nante para a incerteza final das medidas, tornando ineficiente o processo de extração de informação e degradando a sensibilidade da câmara. A maneira clássica de resolver esse problema em sistemas ópticos que operam no infravermelho, onde os efeitos da emissão térmica do ambiente são importantes, é restringir o ângulo sólido subtendido pelos pixels individuais exclusivamente aos raios provenientes do sistema óptico. Para tanto, projeta-se uma imagem real, bastante reduzida, da pupila de entrada do sistema óptico num anteparo que transmita para o sistema de imageamento só o que interessa, bloqueando as contribuições das bordas externas à pupila de entrada, obstrução central do telescópio e sistema de suporte. Como a projeção é realizada em ambiente criogênico, a contribuição térmica espúria é efetivamente eliminada. Nós optamos por um sistema do tipo Offner para implementar na prática esta função. Trata-se de um sistema baseado em espelhos esféricos, bastante compacto e ajustado por construção. A opção por espelhos do mesmo material que o sistema de suporte (Alumínio) minimiza a dilatação diferencial, crítica nesse tipo de aplicação. Apresentamos as soluções detalhadas do projeto óptico-mecânico, bem como uma análise de flexões e desempenho em termos de qualidade de imagem.

Jablonski, F.; Laporte, R.

2003-08-01

78

Mineral Dust Elemental Composition Over the Last 220 Kyr from the EPICA-Dome C ice core (East Antarctica)  

NASA Astrophysics Data System (ADS)

Mineral windblown aerosol (dust) represents a small fraction of the total mass of atmospheric aerosols. However, it may play an important role in climate and, in turn, it is itself sensitive to climatic changes. The investigation of the temporal variability of dust flux as well as the changes of its mineralogical composition within different climatic periods offers a unique way of assessing the source-related environmental changes, the variation in atmospheric circulation, and the potential influence of dust on biogeochemical cycles, for several key elements (such as Si and Fe). The mineral composition of dust found in ice cores is still poorly known, because few techniques are able to provide information on the chemical composition of the insoluble aerosol fraction, because of the very low mass of dust usually present in polar ice samples. Total volume of mineral content is provided by Coulter Counter measurements, and the dust record shows higher dust input during glacial periods than during interglacials (Delmonte et al., 2004). Sr and Nd isotopic tracers for identification of dust provenance to East Antarctica suggest southern South America as the dominant common source for dust in glacial periods of the late Pleistocene (Delmonte et al., 2004), whereas dust provenance during interglacials periods is still highly uncertain. Elemental composition of mineral dust from the Dome C ice core (75° 06' S, 123° 21' E) drilled in the framework of the European Project for Ice Coring in Antarctica (EPICA) is presented, showing measurements obtained by the Proton Induced X-ray Emission (PIXE) technique applied on insoluble atmospheric dust in ice cores. Within this work, substantial improvements to the experimental set-up and data processing have been made, compared to previously presented works on the first 2200 m of the EDC ice core, corresponding to about 220 kyr of climatic history (Marino et al., 2004; Ghermandi et al., 2003). The PIXE technique, based on X-ray spectrometry, allows direct measurements on filters of the insoluble dust fraction without sample pre-treatment, with analytical detection limits less than 1 ppb. The minimum required mass density of sample material on the filter is about 0.1 microg cm-2. Improvements made here allowed us to obtain accurate records of 8 major and minor crustal elements (Si, Al, Fe, Ti, K, Ca, Mg, Na). The data for these 8 elements, as well as their proportions as oxides, are shown for different climatic periods. Because O, Si, Al, Fe, Ti, K, Ca, Mg, Na are the principal constituents (99.90 %) of the Earth's Continental Crust, a comparison with literature data can reveal changes in relative elemental abundances, and hence variable composition of dust under different climatic conditions.

Marino, F.; Maggi, V.; Delmonte, B.; Ghermandi, G.; Petit, J.; Hinkley, T. K.

2004-12-01

79

Recent Developments of the Local Effect Model (LEM) - Implications of clustered damage on cell transformation  

NASA Astrophysics Data System (ADS)

Exposure to radiation of high-energy and highly charged ions (HZE) causes a major risk to human beings, since in long term space explorations about 10 protons per month and about one HZE particle per month hit each cell nucleus (1). Despite the larger number of light ions, the high ionisation power of HZE particles and its corresponding more complex damage represents a major hazard for astronauts. Therefore, in order to get a reasonable risk estimate, it is necessary to take into account the entire mixed radiation field. Frequently, neoplastic cell transformation serves as an indicator for the oncogenic potential of radiation exposure. It can be measured for a small number of ion and energy combinations. However, due to the complexity of the radiation field it is necessary to know the contribution to the radiation damage of each ion species for the entire range of energies. Therefore, a model is required which transfers the few experimental data to other particles with different LETs. We use the Local Effect Model (LEM) (2) with its cluster extension (3) to calculate the relative biological effectiveness (RBE) of neoplastic transformation. It was originally developed in the framework of hadrontherapy and is applicable for a large range of ions and energies. The input parameters for the model include the linear-quadratic parameters for the induction of lethal events as well as for the induction of transformation events per surviving cell. Both processes of cell inactivation and neoplastic transformation per viable cell are combined to eventually yield the RBE for cell transformation. We show that the Local Effect Model is capable of predicting the RBE of neoplastic cell transformation for a broad range of ions and energies. The comparison of experimental data (4) with model calculations shows a reasonable agreement. We find that the cluster extension results in a better representation of the measured RBE values. With this model it should be possible to better predict the risk of the complex mixed radiation field occurring in deep space. 1. F. A. Cucinotta and M. Durante, Lancet Oncol. 7, 431-435 (2006). 2. M. Scholz and G. Kraft, Radiat. Prot. Dosim. 52, 29-33 (1994). 3. Th. Els¨sser and M. Scholz, Radiat. Res. 167, 319-329 (2007). a 4. R. C. Miller, S. A. Marino, D. J. Brenner, S. G. Martin, M. Richards, G. Randers-Pehrson, and E. J. Hall, Radiat. Res. 142, 54-60 (1995).

Elsässer, Thilo

80

Tracing Aeolian dust provenance at Talos Dome (East Antarctica): local versus remote sources  

NASA Astrophysics Data System (ADS)

The Strontium and Neodymium isotopic composition of Aeolian mineral dust is a robust method for mineral dust source tracing. Over the last decade, efforts have been put on the reconstruction of Aeolian dust provenance onto the interior of East Antarctica. These works have been carried out in parallel on both (1) ice core samples and (2) on target samples from the Potential Souce regions of the Southern Hemisphere. Results from Vostok, EPICA-Dome C and other sites from the interior of Antarctica, and comparison with results from potential sources suggested an overall uniform geographic provenance for dust during glacial periods over the last 800.000 years, likely from southern South America (SSA), and different dust source(s) during interglacials. These evidence have been then corroborated by several complementary studies based on dust elemental composition (e.g. Marino et al., 2008), on dust magnetic properties (e.g. Lanci et al., 2008) and dust mineralogical composition (Sala, 2009). Today, a new deep ice core has been drilled in Talos dome (72°48'S, 159°06'E) in the framework of the TALos Dome ICE core drilling project (TALDICE). The site is located on the edge of the East Antarctic Plateau on the opposite side with respect to south America. A preliminary dust concentration and size profile for the TALDICE ice core is available today, and according to preliminary dating it spans about 250 kyrs. Comparison with EDC shows striking similarities for the oldest part of the record and until the deglaciation, but some slight differences arise during the ACR and the beginning of the Holocene. Preliminary results on dust Strontium and Neodymium isotopic fingerprint of TALDICE dust are available. Interestingly the isotopic composition of TALDICE glacial dust is remarkably similar to that obtained from ice core dust samples of similar age from sites located in the East Antarctic interior. Results will be presented and compared with new data from (I) local Antarctic dust sources and (II) from continental areas of the Southern Hemisphere.

Delmonte, B.; Andersson, P. S.; Hansson, M.; Petit, J. R.; Frezzotti, M.; Maggi, V.

2009-04-01

81

Experimental simulation of gravity currents in erodible bed  

NASA Astrophysics Data System (ADS)

Gravity currents are commonly met in nature, when a flow of denser fluid moves into a less dense one. A typical example of a gravity current is given by the sea water which flows into the bottom of a river during the summer, in correspondence of the estuary, when the river's discharge attains low values. In this case, dangerous consequences can occur, because of the polluting of the aquifer caused by the salty water. Density currents also occurs in lakes and reservoirs, because of a change in temperature or because a flood, both can produce some environmental impacts that are of interest to the local water Agency of the different countries. Of particular relevance is also the interaction of the gravity current with the movement of the sediments from the bottom of the bed. The international state of the art is particularly concerned with experimental and numerical investigation on gravity currents on fixed and porous bed [1-2-3], while, to the authors' knowledge, the interaction of a gravity current with an erodible bed is still an open field of investigation. In this paper experiments concerning with the propagation of a gravity current over fixed and erodible bed are presented. The experiments, conducted at the laboratory of Hydraulics of the Universitat Politecnica de Catalunya (actually in the Prof. Bateman's blue room), were concerned with a transparent tank 2 m long, 0.2 m wide and 0.3 m deep, partly filled with salty water and partly with fresh water, up to a depth of 0.28 m. The salty water, whose density was in the range 1050Marino, P.F. Linden, Lock-release inertial gravity currents over a thick porous layer, The Journal of Fluid Mechanics, Vol. 503, 2004 [2] John E. Simpson. Gravity Currents [3] J.J. Monaghan, R.A.F. Cas, A.M. Kos, M. Hallworth, Gravity currents descending a ramp in a stratified tank, The Journal of Fluid Mechanics, Vol. 379, 1999

Bateman, A.; La Roca, M.; Medina, V.

2009-04-01

82

Very Low-Mass Stars and Brown Dwarfs  

NASA Astrophysics Data System (ADS)

Part I. Searches in Clusters, Stellar Associations and the Field: 1. Open clusters after HIPPARCOS J. S. Mermilliod; 2. Proper motions of very low mass stars and brown dwarfs in open clusters N. C. Hambly; 3. Parallaxes for brown dwarfs in clusters C. G. Tinney; 4. Very low mass stars and brown dwarfs in the Belt of Orion S. J. Wolk and F. M. Walter; 5. Photometric surveys in open clusters M. R. Zapatero Osorio; 6. The mass function of the Pleiades R. F. Jameson et al.; 7. Brown dwarfs and the low-mass initial mass function in young clusters K. L. Luhman; 8. Very low mass stars in globular clusters I. R. King and G. Piotto; 9. The DENIS very low mass star and brown dwarf results X. Delfosse and T. Forveille; 10. Preliminary results from the 2MASS core project J. Liebert et al.; Part II. Spectroscopic Properties, Fundamental Parameters and Modelling: 11. Properties of M dwarfs in clusters and the field S. L. Hawley et al.; 12. Spectroscopy of very low mass stars and brown dwarfs in young clusters E. L. Martin; 13. High resolution spectra of L type stars and brown dwarfs G. Basri et al.; 14. Modelling very low mass stars and brown dwarf atmospheres F. Allard; 15. Dust in very cool dwarfs T. Tsuji; 16. On the interpretation of the optical spectra of very cool dwarfs Ya. V. Pavlenko; 17. Absolute dimensions for M type dwarfs A. Gimenez; 18. Theory of very low mass stars and brown dwarfs I. Baraffe; Part III. Convection, Rotation and Acitivity: 19. Convection in low mass stars F. D'Antona; 20. Rotation law and magnetic field in M dwarf models G. Rudiger and M. Kuker; 21. Doppler imaging of cool dwarf stars K. G. Strassmeier; 22. X-ray Emission from cool dwarfs in clusters S. Randich; 23. X-ray variability for dM stars G. Micela and A. Marino; 24. The coronae of AD Leo and EV Lac S. Sciortino et al.; 25. Prospects of vuture X-ray missions for low mass stars and cluster stars R. Pallavicini.

Rebolo, Rafael; Rosa Zapatero-Osorio, Maria

2001-02-01

83

Intermitência alfvênica gerada por caos na atmosfera solar e no vento solar  

NASA Astrophysics Data System (ADS)

Dados medidos no vento solar rápido proveniente dos buracos coronais revelam que os plasmas no meio interplanetário são dominados por flutuações Alfvênicas, caracterizadas por uma alta correlação entre as variações do campo magnético e da velocidade do plasma. As flutuações exibem muitas características esperadas em turbulência magneto-hidrodinâmica totalmente desenvolvida, tais como intermitência e espectros contínuos. Contudo, os mecanismos responsáveis pela evolução de turbulência Alfvênica intermitente não são completamente compreendidos. Neste trabalho a teoria de caos é usada para explicar como sistemas Alfvênicos, modelados pela equação Schrödinger não-linear derivativa e pela equação Kuramoto-Sivashinsky, podem se tornar fortemente caóticos à medida em que parâmetros do plasma são variados. Pequenas perturbações no parâmetro de dissipação podem fazer com que o sistema mude bruscamente de um regime periódico, ou fracamente caótico, para um regime fortemente caótico. As séries temporais das flutuações do campo magnético nos regimes fortemente caóticos exibem comportamento intermitente, em que fases laminares ou fracamente caóticas são interrompidas por fortes estouros caóticos. É mostrado que o regime fortemente caótico é atingido quando as soluções periódicas ou fracamente caóticas globalmente estáveis interagem com soluções do sistema que são fortemente caóticas, mas globalmente instáveis. Estas soluções globalmente instáveis são conjuntos caóticos não-atrativos conhecidos como selas caóticas, e são responsáveis pelos fortes estouros nos regimes intermitentes. Selas caóticas têm sido detectadas experimentalmente em uma grande variedade de sistemas, sendo provável que elas desempenhem um papel importante na turbulência intermitente observada em plasmas espaciais.

Rempel, E. L.; Chian, A. C.-L.; Macau, E. E. N.; Rosa, R. R.

2003-08-01

84

Simulações Numéricas de Rotação Nuclear Cometária  

NASA Astrophysics Data System (ADS)

Este trabalho apresenta os resultados iniciais de simulações numéricas da evolução rotacional, de um núcleo cometário não esférico, ao longo de uma passagem periélica, levando-se em conta os torques devido a existência dos jatos de poeira e de gás. Inicialmente os autores apresentam um modelo simples (primeira aproximação), com somente um único jato na extremidade do semi-eixo maior, para compreender a variação positiva ou negativa que estas forças não gravitacionais exercem sobre o período de rotação cometário. Posteriormente incrementa-se o número de jatos, os quais são distribuídos ao longo da superfície cometária, para observar-se a contribuição dos efeitos provenientes dos torques originários da liberação da poeira e gás cometários, que provavelmente violará a suposição da livre precessão. Os estados rotacionais, sob torques induzidos devido à sublimação, dependem fortemente da localização das áreas ativas do núcleo. Os cometas P/Schwassmann-Wachmann 1, P/Tempel 2, P/Forbes e C/Meunier-Dupouy serão observados fotometricamente, pelos autores, no Laboratório Nacional de Astrofísica (LNA) ao longo de algumas noites consecutivas em abril, junho e julho de 1999. Estas observações serão comparadas com as simulações numéricas de rotação cometária.

Voelzke, M. R.; Winter, O. C.

1999-08-01

85

Sobre el estado evolutivo de ? Pictoris  

NASA Astrophysics Data System (ADS)

Desde el descubrimiento de fuertes excesos infrarrojos en ? Pictoris, esta estrella ha sido muy estudiada y es considerada candidata a poseer un sistema planetario propio. ? Pic está rodeada de un disco asimétrico de polvo que se observa de canto y que esta vacío a distancias <= 40 AU. Esto se considera una fuerte evidencia en favor de la presencia de (al menos) un planeta gigante. Recientemente se han observado líneas de material circunestelar que se han interpretado como consecuencia de la caída de objetos cometarios sobre esta estrella. Recientemente se ha utilizado la existencia del disco de polvo para atribuir una edad corta (pre - secuencia principal) a ?Pic. Sin embargo, la evaporación de estos cometas provee suficiente polvo como para explicar la presencia del disco observado sin necesidad de edades cortas. En este trabajo mostramos que la comparación entre la tasa de impactos cometarios estimada en el Sistema Solar para diferentes etapas de su evolución y los datos observados en ? Pic indica edades avanzadas para ? Pic. Esta estimación debe tomarse con cautela ya que depende de la estructura de los sistemas planetarios. Además mostramos que, desde el punto de vista de la evolución estelar y con las incertezas presentes en la luminosidad y la temperatura efectiva, existe un continuo de edades posible para ? Pic. Sin embargo, empleando los datos provenientes de los flujos cometarios encontramos que una edad prolongada es consistente con ambos tratamientos.

Brunini, A.; Benvenuto, O. G.

86

Esquizofrenia y trastorno en el consumo de sustancias: prevalencia y character?sticas sociodemogr?ficas en la poblaci?n Latina  

PubMed Central

El interés por comprender la co-morbilidad de la esquizofrenia y el trastorno en el uso de sustancias, ha aumentado debido al incremento de este diagnóstico, a los efectos negativos observados en el sujeto y a los costos en los servicios de salud. Este trastorno dual puede tener efectos dramáticos en el curso clínico del trastorno psicótico tales como: mayores recaídas, re-hospitalizaciones, síntomas más severos, no adherencia al tratamiento antipsicótico, cambios marcados del humor, aumento en el grado de hostilidad e ideación suicida, así como alteraciones en otras áreas del funcionamiento incluyendo violencia, victimización, indigencia y problemas legales. La literatura proveniente en particular de Estados Unidos y Europa sugiere que el rango de prevalencia para este diagnóstico puede oscilar entre el 10% hasta el 70%. En este estudio, revisamos la prevalencia del diagnóstico dual de esquizofrenia y trastorno en el uso sustancias, así como sus características sociodemográficas, con base en la literatura disponible alrededor del mundo dando énfasis en la poblacion latina. A pesar de que este diagnóstico es ampliamente aceptado, se conoce poco sobre su prevalencia en la población latina, sobre los factores ambientales, demográficos, clínicos y otras características de estos individuos. Un mejor conocimiento sobre este diagnóstico permitiría mejorar los métodos para la detección y adecuada valoración del trastorno en el uso de sustancias en personas con trastornos metales severos como la esquizofrenia.

Jimenez-Castro, Lorena; Raventos-Vorst, Henriette; Escamilla, Michael

2012-01-01

87

Some mathematical aspects of quantum field theory  

NASA Astrophysics Data System (ADS)

In recent years, physics especially Quantum Field Theory has had an enormous impact in mathematics. This thesis mainly contains two different parts of mathematical developments of problems inspired from physics. Firstly, I study Topological Quantum Field Theory and its related topics. Gromov-Witten theory of resolved conifold corresponds to the Chern-Simons theory of unknot. In a series of papers, Labastida, Marino, Ooguri, Vafa, proposed a conjectural description of Chern-Simons theory of special linear quantum group invariants of links. LMOV conjecture could be viewed as a counterpart of Gopakumar-Vafa conjecture. These are actually parts of the big picture, large N Chern-Simons/Topological string duality. In the first chapter of this part, the orthogonal quantum group version of LMOV conjecture is rigorously formulated in mathematics by using the representation of Brauer centralizer algebra. We also obtain formulae of Lichorish-Millet type which could be viewed as the application in knot theory and topology. By using the cabling technique, we obtain a uniform formula of colored Kauffman polynomial for all torus links with all partitions. Combined these together, we are able to prove many interesting cases of this orthogonal LMOV conjecture. In particular we can apply this uniform formula to verify certain case of the conjecture at roots of unity. In fact, these integer coefficients appeared in the original (orthogonal) LMOV conjecture are called the BPS numbers in string theory. In the second chapter of this part, graphic representations of the universal R-matrices has been used to discover the recursion formulae between various quantum group invariants. We study the recursion relations of R-matrices corresponding to the inclusions Uq( sln) ? Uq(sl n+1), Uq(sl k) x Uq(sln--k ) ? Uq(sln), Uq(sln) ? U q(so2n), Uq(so2k) x Uq(sln--k) ? Uq(so2n). As an application, we find the ODE recursion formulae for HOMFLY and Kauffman polynomials. Secondly, I study the Modular Forms in Topology, Elliptic Genera, Loop Space and String Manifolds. In a series of papers, the following results are discovered. By developing modular invariance on certain characteristic forms, several cancellation formulas emerge naturally as the generalization of the original gravity anomaly cancellation formulas obtained by L. Alvarez-Gaume and E. Witten in their celebrated paper [2] studying the string theory. These cancellation formulae directly imply the divisibility and the congruence phenomena of characteristic numbers by Atiyah-Singer Index theorem, which plays important roles both in topology and differential geometry. We recover the Hirzebruch divisibility of twist signature and obtain the twist higher Rokhlin congruence by applying the modular invariance properties on the elliptic forms and also prove that it is best possible by studying examples constructed from K3-surface and Bott manifold. We also obtain the divisibility results for the index of double twist signature operators. By studying the "modular transgression" on elliptic forms, we obtain some modularly invariant secondary characteristic forms on odd dimensional manifolds. Also, by using this method, we heuristically calculate the Chern-Simons forms for flat bundles over free loop space. This direction is pioneered by Witten [94), who heuristically interpreted the Landweber-Stong elliptic genus as the index of the formal signature operator on free loop space as well as introduced the formal equivariant index of the Dirac operator on loop space, known as Witten operator. We call a manifold to be string if its loop space is spin. It's known that a string manifold is a spin manifold with vanishing half first Pontryagin class. Using the arithmetic properties of Jacobi-Theta functions, we prove the vanishing of the Witten genus of certain nonsingular string complete intersections in products of complex projective spaces, which generalizes a known result of Landweber and Stong [54].

Chen, Qingtao

88

Coerência espectroscópica de famílias de asteróides  

NASA Astrophysics Data System (ADS)

As Famílias de asteróides são caracterizadas como agrupamentos de objetos provenientes da quebra por colisão de corpos precursores. Desta forma, seus membros devem preservar relações genéticas que podem ser traduzidas sob a análise de suas características espectrais. Neste trabalho é apresentado o primeiro estudo espectroscópico de todas as famílias de asteróides do cinturão principal. Para tal, a divisão em famílias foi refeita utilizando-se o método HCM com uma base de elementos próprios analíticos (Knezevic e Milani, Jun 2001) e para o estudo espectroscópico foram utilizadas diversas campanhas de observação espectroscópica, tais o S3OS2 e o SMASSII, bem como outros dados disponíveis na literatura. A homogeneidade espectroscópica de cada família foi avaliada através da verificação das classes espectroscópicas presentes, bem como da comparação destes espectros com os de objetos de fundo, localizados na vizinhança da família. Vinte e duas famílias foram analisadas (as que possuíam mais do que 3 membros com espectro) e, dentre as principais conclusões pode-se citar a homogeneidade espectroscópica e, provavelmente mineralógica das famílias de Vesta, Eunomia, Hoffmeister, Dora, Merxia, Agnia, Koronis e Veritas. Esta última em particular, foi tida como uma família não homogênea espectroscopicamente em trabalho anterior (Di Martino et al. 1997). Outro resultado interessante é, por um lado, a aparente falta de homogeneidade dos membros da família de Eos, e por outro sua forte distinção dos objetos de fundo. O oposto ocorre na família de Themis, esta apresentando-se espectroscopicamente compatível com os objetos de fundo, mas com grande homogeneidade taxonômica entre seus membros. Algumas das famílias apresentam asteróides "intrusos" (objetos cujas características físicas não são compatíveis com aquelas dos membros da família) que, de modo geral desaparecem ao se considerarem níveis mais baixos de corte para a divisão da família no HCM, sem prejuízo para o agrupamento dos demais membros.

Mothé Diniz, T.; Roig, F. V.

2003-08-01

89

Transferências orbitais dentro do modelo quase bicircular no sistema Terra-Lua-Sol  

NASA Astrophysics Data System (ADS)

O problema quase bicircular planar consiste na determinação da dinâmica de um corpo, de massa desprezível, que se move sob o campo gravitacional de três corpos. No caso estudado, o quarto corpo é considerado um satélite artificial e os demais são a Terra, a Lua e o Sol, formando o sistema de três corpos. Este modelo permite a construção de uma hamiltoniana similar a do problema restrito de três corpos (PRTC), incluindo termos periódicos não autônomos, provenientes da presença do Sol, portanto pode ser entendido como uma perturbação ao PRTC. Suas órbitas periódicas aparecem isoladas e possuem o mesmo período solar. Os pontos de equilíbrio colineares possuem o mesmo caráter de estabilidade linear dos pontos lagrangianos (L1, L2 e L3) do PRTC, sendo do tipo sela x centro x centro, instável na direção x e estáveis nas direções y e z. As órbitas periódicas tridimensionais ao redor do ponto colinear é chamada órbita Halo. O objetivo deste trabalho é determinar órbitas de transferências de baixo consumo de combustível para um veículo espacial partindo de uma órbita de estacionamento ao redor da Terra em direção a uma órbita Halo do ponto L1, situado entre a Terra e Lua. Esta tarefa pode ser transformada no problema de valor de contorno: dado um ponto inicial na órbita de estacionamento, um ponto final na órbita halo e o tempo de transferência, deseja-se obter a trajetória que liga estes dois pontos e que minimize os incrementos de velocidade do veículo. Essas transferências são realizadas baseadas no método de Lambert e analisadas de modo a fornecer um baixo consumo. Posteriormente, é feita uma comparação de consumo com as órbitas de transferência equivalentes do PRTC.

Corrêa, A. A.; de Almeida Prado, A. F. B.; Stuchi, T. J.; Beaugé, C.

2003-08-01

90

Um estudo espectrofotométrico da variável cataclísmica V3885 Sgr  

NASA Astrophysics Data System (ADS)

Variáveis Cataclísmicas são sistemas binários cerrados compostos de uma anã vermelha que transfere matéria para uma anã branca, em sistemas não magnéticos ocorre a formação de um disco de acresção em torno da anã branca. V3885 Sgr é uma variável cataclísmica classificada como sendo do tipo nova-like. É apresentado um estudo espectrofotométrico de V3885 Sgr de alta resolução temporal feito na região do visível. A região observada é centrada em Ha e abrange também a linha de HeI 6678. O primeiro resultado obtido neste estudo é a determinação do período orbital a partir de medidas da velocidade radial da linha de Ha como sendo 0,20716071(22) dias, resolvendo inconsistências quanto a esse valor na literatura e definindo uma efeméride a longo prazo para o sistema. Com este período e as medidas de velocidade radial do perfil de linha de Ha foi construído um diagrama de massas, através do qual restringimos as massas das componentes estelares do sistema e limitamos a inclinação orbital do sistema. Foram construídos diagramas de Greenstein para as linhas de Ha e HeI, onde os espectros médios em cada intervalo de fase são representados lado a lado em escala de cinza, indicando a existência de uma emissão intensa proveniente da parte posterior do disco. A partir da tomografia Doppler obtivemos perfis de emissividade radial para o disco tanto para a linha de Ha como para HeI. Os resultados obtidos são comparados com os de outros sistemas estudados com a mesma técnica. Serão apresentados também resultados da tomografia de flickering para o sistema.

Ribeiro, F. M. A.; Diaz, M. P.

2003-08-01

91

The migration, dissolution, and fate of chlorinated solvents in the urbanized alluvial valleys of the southwestern USA  

NASA Astrophysics Data System (ADS)

The migration, dissolution, and subsequent fate of spilled chlorinated solvents in the urban alluvial valleys of the southwestern U.S. appear to be governed by a unique set of hydrogeologic and geochemical processes occurring within terrigeneous clastic depositional systems. The alluvial and lacustrine fill of the basins, the trapping of solvents in fine-grained sediments beneath the urbanized valley centers, the oxic conditions typical of the deeper alluvium, and the contaminant-transport patterns produced by large-scale basin pumping combine to produce long aqueous-phase plumes derived from the dissolution of trapped chlorinated solvents. Although of limited aqueous solubility, these dense solvents are sufficiently mobile and soluble in the southwestern alluvial valleys to have produced aqueous plumes that have migrated several kilometers through the deeper alluvium and have contaminated valuable water-supply well fields in California, Arizona, and New Mexico. The typical length of these plumes and the presence of oxic groundwater indicate that it is unlikely that natural attenuation will be a practical remedial option in the southwestern alluvial valleys or in other alluvial systems in which similar hydrogeologic and geochemical conditions exist. Résumé La migration, la dissolution et l'évolution consécutive des rejets de solvants chlorés dans les vallées alluviales du sud-ouest des États-Unis paraissent déterminées par un même ensemble de processus hydrogéologiques et géochimiques intervenant dans des formations de dépôts clastiques terrigènes. Les remplissages alluviaux et lacustres des bassins, le piégeage des solvants par des sédiments fins sous les centres des vallées urbanisées, les conditions oxiques typiques des alluvions plus profondes et les types de transport de contaminants provoqués par le pompage à l'échelle du bassin se combinent pour produire des panaches, étendus dans la phase aqueuse, provenant de la dissolution de solvants chlorés piégés. Malgré leur faible solubilité dans l'eau, ces solvants denses sont suffisamment mobiles et solubles pour avoir produit, dans le sud-ouest des vallées alluviales, des panaches aqueux qui ont migré de plusieurs kilomètres dans les alluvions plus profondes et ont contaminé des champs captants pour l'eau potable en Californie, en Arizona et au Nouveau-Mexique. La longueur de ces panaches et la présence d'eau souterraine en conditions oxiques indiquent qu'il est peu probable que la décroissance naturelle soit un recours pratique de décontamination dans les vallées alluviales du sud-ouest ou dans d'autres systèmes alluviaux dans lesquels existent des conditions hydrogéologiques et géochimiques semblables. Resumen La migración, disolución y transporte de compuestos clorados en valles aluviales urbanos del sudoeste de los Estados Unidos de América parecen estar gobernados por un conjunto único de procesos hidrogeológicos y geoquímicos que tienen lugar en los depósitos clásticos. El relleno aluvial y lacustre de las cuencas, la inmovilización de los solutos en sedimentos de grano fino bajo las zonas urbanizadas, los condiciones óxicas típicas del aluvial profundo y las direcciones de transporte regidas por los fuertes bombeos en las cuencas se combinan para producir grandes penachos en fase acuosa procedentes de la disolución de los compuestos clorados atrapados en el medio. Aunque la solubilidad de estos compuestos clorados densos es pequeña, es suficiente para producir penachos que en algunos casos se han desplazado varios kilómetros a través del aluvial profundo y han llegado a contaminar zonas de extracción muy productivas en California, Arizona y Nuevo México. La longitud de estos penachos y la presencia de agua subterránea oxidante indican que es improbable que la degradación natural sea un buen método de limpieza de estos acuíferos o de otros sistemas aluviales que presenten características hidrogeológicas y geoquímicas semejantes.

Jackson, R. E.

92

Microbial degradation of chloroethenes in groundwater systems  

NASA Astrophysics Data System (ADS)

The chloroethenes, tetrachloroethene (PCE) and trichloroethene (TCE) are among the most common contaminants detected in groundwater systems. As recently as 1980, the consensus was that chloroethene compounds were not significantly biodegradable in groundwater. Consequently, efforts to remediate chloroethene-contaminated groundwater were limited to largely unsuccessful pump-and-treat attempts. Subsequent investigation revealed that under reducing conditions, aquifer microorganisms can reductively dechlorinate PCE and TCE to the less chlorinated daughter products dichloroethene (DCE) and vinyl chloride (VC). Although recent laboratory studies conducted with halorespiring microorganisms suggest that complete reduction to ethene is possible, in the majority of groundwater systems reductive dechlorination apparently stops at DCE or VC. However, recent investigations conducted with aquifer and stream-bed sediments have demonstrated that microbial oxidation of these reduced daughter products can be significant under anaerobic redox conditions. The combination of reductive dechlorination of PCE and TCE under anaerobic conditions followed by anaerobic microbial oxidation of DCE and VC provides a possible microbial pathway for complete degradation of chloroethene contaminants in groundwater systems. Résumé Les chloroéthanes, tétrachloroéthane (PCE) et trichloroéthane (TCE) sont parmi les polluants les plus communs trouvés dans les aquifères. Depuis les années 1980, on considère que les chloroéthanes ne sont pas significativement biodégradables dans les aquifères. Par conséquent, les efforts pour dépolluer les nappes contaminées par des chloroéthanes se sont limités à des tentatives de pompage-traitement globalement sans succès. Des travaux ultérieurs ont montré que dans des conditions réductrices, des micro-organismes présents dans les aquifères peuvent, par réduction, dégrader les PCE et TCE en composés moins chlorés, comme le dichloréthane (DCE) et le chlorure de vinyl (VC). Bien que des études de laboratoire réalisées avec des micro-organismes adaptés aux composés halogénés montrent que la réduction complète en éthane est possible, dans la plupart des nappes la réaction de déchloration par réduction s'arrête apparemment au DCE et au VC. Cependant, des recherches récentes menées sur des sédiments d'un aquifère et d'alluvions ont démontré que l'oxydation microbienne de ces descendants réduits peut se produire de manière significative dans des conditions de redox anérobies. La déchloration par réduction de PCE et de TCE dans des conditions anérobies suivie par une oxydation microbienne anérobie des DCE et VC fournit une piste microbienne possible pour obtenir une dégradation complète des chloroéthanes polluants dans les aquifères. Resumen Los cloroetanos (tetracloroetano PCE y tricloroetano TCE) son contaminantes muy habituales en los acuíferos. Hasta 1980 se consideraba que los cloroetanos no eran biodegradables y, por tanto, los métodos de rehabilitación en acuíferos contaminados con cloroetanos se limitaban al pump-and-treat, generalmente con poco éxito. Posteriormente se vio que, en condiciones reductoras, algunos microorganismos pueden reducir PCE y TCE a unos subproductos menos clorados, como el dicloroetano (DCE) y el cloruro de vinilo (VC). Aunque estudios de laboratorio recientes sugieren que la reducción completa a etano es posible, en la mayoría de los sistemas acuíferos la decloración suele detenerse en los DCE o VC. Sin embargo, investigaciones más recientes en acuíferos y sedimentos fluviales demuestran que la oxidación microbiana de estos subproductos puede ser importante bajo condiciones redox anaerobias. La combinación de la reducción de PCE y TCE en condiciones anaerobias seguida de la oxidación microbiana anaerobia de DCE y VC proporciona un método potencial para la degradación total de los cloroetanos en los sistemas acuíferos.

Bradley, Paul M.

93

Magnetic and ground penetrating radar surveys for the research of Medieval settlements in the inland of the Marche Region (Italy)  

NASA Astrophysics Data System (ADS)

This work was carried out in the framework of the R.I.M.E.M. project (Research on Medieval settlements in the inland of the Marche Region, Italy.) leaded by the Universities of Macerata and Udine and having the aim to produce a significant contribution for the comprehension of the settlement process in the Central and Southern Italy during the Late Roman Period and Early Middle Ages. Then, an extensive gradiometric survey were carried out, by using a vapour caesium magnetometer, in the area included amongst the municipal districts of Caldarola, Cessapalombo and San Ginesio, sited in the area closed to Macerata between the valleys of Chienti and Fiastra rivers. Moreover, in the most interesting areas, a 400 MHz 3D ground penetrating radar (GPR)survey was carried out in order to get the precise overlapping with the magnetic method. The Magnetic method is now a standard practice in the archaeological research taken into great consideration for its non-destructivity and quickness and its capability of mapping wide areas in quite a short lapse of time (Bavusi et al., 2008). Moreover the method provides an information well correlable with remote sensing data (Gallo et al, 2008). The GPR method is extremely useful for archaeologists thanks to its non-destructivity and capability of giving real-time and high-resolution data (Basile et al., 2000). Today the effectiveness of this method was improved by powerful 3D visualisation methods as well as 3D space, time or depth slices and iso-amplitude surfaces, too (Nuzzo et al., 2002). The integrations of several geophysical methods are usual (Sambuelli et al.1999, De Domenico et al., 2001; Chianese et al., 2004) particularly when a simple comparison in cross section along the same profiles can be performed. In this work the overlapping between two kinds of data was complicated by different outputs coming from two methods: maps for the magnetic method and cross sections for the GPR one. The 3D survey design for the GPR survey and a complex processing routine was carried out in order to get both data volumes and time slices, more easily comparable with magnetic maps. Magnetic data processing included spike removal and destripe. Finally, the results revealed the presence of several target of archaeological interest and, where two methods were carried out, the results are consistent. M. Bavusi , A. Giocoli, e. Rizzo, v. Lapenna (2008). Geophysical characterisation of Carlo' s V Castle (Crotone, Italy). Journal of Applied Geophysics. DOI: 10.1016/j.jappgeo.2008.09.002. Basile V., Carrozzo M.T., Negri S., Nuzzo L., Quarta T., Villani A.V., (2000). A ground-penetrating radar survey for archaeological investigations in an urban area - Lecce, Italy. Journal of Applied Geophysics, 44, 15-32. Chianese D., D'Emilio M., Di Salvia S., Lapenna V., Ragosta M., Rizzo E. (2004). Magnetic Mapping, Ground Penetrating Radar Surveys and Magnetic Susceptibility Measurements for the Study of the Archaeological Site of Serra di Vaglio (Southern Italy). Journal of Archaeological Science, 31, 633-643. De Domenico D., Giannino F., Marino A., Nuzzo L., Rizzo E., (2001). Indagini elettriche e radar: integrazione dei metodi nello studio dei resti sepolti del monastero normanno in s. Marco D'Alunzio (Messina). Atti del 21° Convegno Nazionale del GNGTS, 351-353. GalloD., Ciminale M., Beckerb H. and Masini N. (2008). Remote sensing techniques for reconstructing a vast Neolithic settlement in Southern Italy. Journal of Archaeological Science, DOI:10.1016/j.jas.2008.07.002. Nuzzo L., Leucci, G . Negri S., Carrozzo M. T. and Quarta T., (2002). Application of 3D visualization techniques in the analysis of GPR data for archaeology. Annals of Geophysics, 45 (2), 321-337. Sambuelli L., Socco L.V., Brecciaroli L., (1999). Acquisition and processing of electric, magnetic and GPR data on a Roman site(Victimulae, Salussola, Biella), Journal of Applied Geophysics, 41, 189-204

Bavusi, M.; Giocoli, A.; Balasco, M.; Favulli, G.; Moscatelli, U.; Minguzzi, S.; Gnesi, D.; Virgili, S.

2009-04-01

94

Courtship behavior of different wild strains of Ceratitis Capitata (Diptera: Tephritidae)  

SciTech Connect

This study documents differences in the courtship behavior of wild strains of Ceratitis capitata (Wiedemann) from Madeira (Portugal), Hawaii (U.S.A.), Costa Rica, and Patagonia (Argentina). Some traits showed large variations and others substantial overlaps. The angle at which the male faced toward the female at the moment of transition from continuous wing vibration and intermittent buzzing changed very little during the course of courtship in all strains, but males from Madeira tended to face more directly toward the female than other males. Females tended to look more, and more directly, toward the males as courtship progressed in all strains. The distance between male and female tended to decrease as courtship proceeded in all strains, but the distances at which males initiated continuous vibration, intermittent buzzing, and jumped onto the female were relatively less variable between strains, except for the strain from Costa Rica. Flies of Madeira courted for longer and the male moved his head and buzzed his wings longer than the other strains. (author) [Spanish] Este estudio documenta diferencias en el comportamiento de cortejo de cepas silvestres de Ceratitis capitata (Wied.) provenientes de Madeira (Portugal), Hawaii (Estados Unidos de Norte America), Costa Rica y Patagonia (Argentina). Algunas caracteristicas mostraron grandes variaciones y traslape substancial. Los angulos a los cuales los machos miraron hacia las hembras cambiaron muy poco en el momento de la transicion de la vibracion continua al zumbido intermitente durante el curso del cortejo en todo las cepas, pero los machos de Madeira tendieron a enfrentar mas directamente a la hembra que otros machos. Los angulos de las hembras disminuyeron claramente durante el cortejo en todas las cepas. La distancia entre el macho y la hembra tendio a disminuir conforme el cortejo continuaba en todas las cepas, pero las distancias a las cuales los machos iniciaron la vibracion continua, el zumbido intermitente, y el salto sobre la hembra eran relativamente menos variables entre cepas excepto la cepa de Costa Rica. Moscas de Madeira cortejaron mas tiempo y el macho moviosu cabeza y zumbaba sus alas mas prolongadamente que las otras cepas. (author)

Briceno, D. [Escuela de Biologia, Universidad de Costa Rica, Ciudad Universitaria (Costa Rica); Eberhard, W. [Escuela de Biologia, Universidad de Costa Rica, Ciudad Universitaria and Smithsonian Tropical Research Institute (Costa Rica); Vilardi, J. [Dpto. de Ciencias Biologicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina); Cayol, J.-P. [Technical Cooperation Division, IAEA, Wagramerstrasse 5, P.O. Box 100 A-1400, Vienna (Austria); Shelly, T. [A. C. , D. , E. USDA/APHIS/CPHST, 41-650 Ahiki St. Waimanalo, HI 96795 (United States)

2007-03-15

95

Correlação de longo alcance em sistemas binários de raios-x usando remoção de flutuações  

NASA Astrophysics Data System (ADS)

Neste trabalho é proposta uma metodologia de analise de series temporais de fontes astrofísicas, baseada no método proposto por Peng et al. (1994) e Liu et al. (1999), o qual consiste na idéia de que uma série temporal correlacionada pode ser mapeada por um processo de busca de auto-similaridades em diversas escalas de tempo n. Removendo as eventuais tendências e integrando o sinal observado, é obtida uma medida do desvio médio quadrático das flutuações do sinal integrado F(n)~na, onde a representa o fator de escala associado com a auto-similaridade da correlação de longo alcance do sinal. Baseado nos valores obtidos de a, é possível distinguir entre os casos de sinais não-correlacionados, tipo ruído branco (a = 0,5), sinal anti-persistentes (a < 0,5) e sinal persistente (a > 0,5). Usando esta metodologia, foram analisadas 129 curvas de luz de sistemas binários de raios-X, provenientes do banco de dados públicos de observações feitas pelo instrumento All Sky Monitor, a bordo do satélite Rossi X-Ray Timing Explorer (ASM-RXTE). Foram identificadas a presença de a'0,5 em mais de 90% dos sistemas estudados, implicando em dizer que as flutuações de intensidade observadas apresentam correlação de auto-similaridade, sem entretanto, indícios de apresentarem uma escala de tempo característica das flutuações de intensidade. Sistemas onde são observadas erupções (flares), apresentam sistematicamente a > 0,5, característica esta, possivelmente associada com persistência das flutuações de densidade de disco ou taxa de acréscimo de massa. Os sistemas com curvas de luz onde nao são observadas as erupções apresentam uma distribuição normal centrada em a~0,62+/-0,10. Referências ¾ Peng, C.-K., Buldyrev, S.V., Havlin, S., Simons, M., Stanley, H.E., e Goldberg, A.L., Phys. Rev. E, (49), 1685 (1994). ¾ Liu, Y., Gopikrishnan, P., Cizeau, P., Meyer, M., Peng,C.-K., e Stanley, H.E., Phys. Rev. E, (60), 1390 (1999).

Pereira, M. G.; Moret, M. A.; Zebende, G. F.; Nogueira, E., Jr.

2003-08-01

96

Sexual competitiveness and compatibility between mass-reared sterile flies and wild populations of Anastrepha Ludens (Diptera: Tephritidae) from different regions in Mexico  

SciTech Connect

The mass-reared colony of Anastrepha ludens (Loew) currently used in Mexico for suppression of the Mexican fruit fly has been in use for over 10 years. Sterile flies are released into a wide range of environmental conditions as part of an integrated area-wide approach to suppress diverse populations of this pest in the Mexican Republic. This paper assesses the performance of the sterile flies interacting with wild populations from the different environments. We investigated the sexual compatibility and competitiveness of the sterile flies when competing with wild populations from 6 representatives Mexican states: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan, and Chiapas. Results show that the males of the wild populations differed in the time to the onset and peak of sexual activity. Nevertheless, the index of sexual isolation (ISI) reflected sexual compatibility between the populations and the mass-reared strain, indicating that the sterile individuals mate satisfactorily with the wild populations from the 6 states. The male relative performance index (MRPI) showed that the sterile male is as effective in copulating as the wild males. The female relative performance index (FRPI) reflected a general tendency for wild females to copulate in greater proportion than the sterile females, except for the strains from Tamaulipas and Chiapas. In general, the lower participation of the sterile females in copulation increases the possibilities of sterile males to mate with wild females. The relative sterility index (RSI) showed that the acceptance by wild females of the sterile males (25-55%) was similar to that of wild males. Females of the Chiapas strain showed the lowest acceptance of sterile males. Finally, the results obtained in the Fried test (which measures induced sterility in eggs) showed a competitiveness coefficient ranging from 0.2 to 0.5. This suggests that sterile males successfully compete and are compatible with flies from different geographic origins. (author) [Spanish] La colonia actualmente usada para controlar la mosca mexicana de la fruta, Anastrepha ludens (Loew), en Mexico tiene mas de 10 anos en cria masiva. Los insectos esteriles son liberados en una gran variedad de condiciones ambientales como parte de un control integrado para suprimir diversas poblaciones de esta plaga dentro de la Republica Mexicana. El objetivo de este documento esta dirigido a revisar el desempeno de las moscas esteriles frente a poblaciones silvestres procedentes de diferentes ambientes y para esto se realizaron comparaciones de compatibilidad y competitividad sexual de las moscas esteriles contra poblaciones silvestres de seis estados representativos de la Republica Mexicana: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan y Chiapas. Los resultados obtenidos manifiestan diferencias en el horario de inicio de llamado y mayor actividad sexual del macho entre las moscas provenientes de cada estado. Sin embargo el indice de aislamiento (ISI) reflejo compatibilidad sexual entre la cepa de laboratorio y todas las poblaciones analizadas, indicando que los individuos esteriles pueden aparearse satisfactoriamente con las poblaciones silvestres de los seis estados. El indice de efectividad de apareamiento del macho (MRPI) reflejo de manera global que los machos esteriles son tan efectivos para copular como los silvestres. El indice de efectividad de apareamiento de la hembra (FRPI) reflejo que en la mayoria de los estados las hembras silvestres copularon en mayor proporcion que las hembras esteriles, excepto para las poblaciones de Tamaulipas y Chiapas. En general, la baja participacion de las hembras esteriles en el campo permitio al macho esteril ampliar su probabilidad de apareamiento con las hembras silvestres. En cuanto al indice de esterilidad relativa (RSI), observamos que la aceptacion de las hembras silvestres al macho esteril (25-55%) fue similar a la de los machos silvestres. Las hembras de la poblacion de Chiapas registro la menor aceptacion. Finalmente, los resultados obtenidos en la prueba de Fried, la cual determi

Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J. [Programa Moscamed Moscafrut-Desarrollo de Metodos, Central Poniente No. 14 altos-Esq. 2a Avenida Sur. CP 30700 Tapachula, Chiapas (Mexico)

2007-03-15