981 resultados para post-implantation losses


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Whole-lake techniques are increasingly being used to selectively remove exotic plants, including Eurasian watermilfoil ( Myriophyllum spicatum L.). Fluridone (1-methyl-3-phenyl- 5-[3-(trifluoromethyl)phenyl]-4(1 H )-pyridinone), a systemic whole-lake herbicide, is selective for Eurasian watermilfoil within a narrow low concentration range. Because fluridone applications have the potential for large effects on plant assemblages and lake food webs, they should be evaluated at the whole-lake scale. We examined effects of low-dose (5 to 8 ppb) fluridone applications by comparing submersed plant assemblages, water quality and largemouth bass ( Micropterus salmoides ) growth rates and diets between three reference lakes and three treatment lakes one- and two-years post treatment. In the treatment lakes, fluridone reduced Eurasian watermilfoil cover without reducing native plant cover, although the duration of Eurasian watermilfoil reduction varied among treatment lakes. (PDF has 11 pages.)

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[ES]Este trabajo se centra en el análisis de la relación entre las políticas crediticias de las entidades de crédito y el comportamiento de las mismas ex post. Se hace una revisión de la teoría que justifica que los mercados crediticios pueden estar sujetos, en determinadas circunstancias, a un componente endógeno más elevado de lo que, en general, se atribuye. Se plantea como hipótesis de trabajo la existencia de una relación entre la intensidad en el crecimiento de la cartera crediticia de los bancos en las fases de expansión crediticia y su comportamiento ex post. Los resultados preliminares presentados confirman la hipótesis de que las entidades que más desvían su crecimiento crediticio respecto del crecimiento del PIB nominal, están sujetas a un peor comportamiento en cuanto a la evolución posterior de sus beneficios, rentabilidades e insolvencias.

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© Este trabajo está licenciado bajo la licencia Creative Commons Attribution 3.0.

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Proiektu honetan zehar Itzulpen Automatikoa eta horren inguruko tresnen inguruan jorratu da. Lengoaia Naturalaren Prozesamendua eta itzulpen automatikoa ikasi eta aztertu egin dira ikuspuntu zabal batetik. Itzulpen automatiko orokorraz eta horren aplikazio mota desberdinetatik gain, bestelako kontzeptuak ere tratatu dira, hala nola, itzulpenean laguntzeko tresnak, itzulpen automatikoaren ebaluazioa eta itzulpen automatikorako testuen aurre-edizioa eta post-edizioa. Ikasketa- eta aztertze-prozesu horretaz gain, erlazionatuta dauden tresnak erabili edota moldatu egin dira euskararako itzulpen automatikoan barne. Hiru atal nagusi nabarmendu daitezke: Lehenengo, OmegaT, itzulpenean laguntzeko softwarea, moldatu da Matxin euskararako itzultzaile automatikoa gehituz. Gainera, IXA Taldearen eta Euskal Wikipediaren arteko kolaborazio-lanean, Wikipediako artikuluak eskuratu, itzuli eta igotzeko aukera egokitu zaio OmegaT-ri eta horren erabilera sustatu da Euskal Wikipediako komunitatean eta UPV/EHUko Informatikako ikasle eta irakaslegoaren artean. Bestalde, lan honetaz baliatuz, OmegaT-k sortzen dituen itzulpen-memoriak, Matxin-en itzulpenen gaineko post-edizioan oinarrituak, eskuratzeko modu bat egin da, horiekin Matxin-en funtzionamendua hobetu ahal izateko. Ondoren, Asiya programan integratu egin da euskara. Asiya-k itzulpen automatikoaren ebaluazio eta meta-ebaluazioak egin ditzakeen aplikazioa da. Hainbat metrika aztertu dira euskara aztertzeko balio ote duten begiratzeko. Besteen artean, lau metrikari euskara gehitzeko saiakera egin nahi izan da IXA Taldeko euskarazko testuen analizatzaile batek eskainitako informazio sintaktikoa gehituz, baina bi metrika soilik egokitu ahal izan dira. Azkenik, DiSeg esaldi-segmentatzailea erabili egin da gaztelerazko corpus baten gainean esaldi luzeak banatzeko. Aurre-edizio hori eta gero itzuli egin dira eta Asiya erabiliz emaitzen ebaluazioa eta konparazioa egin dira, esaldi laburragoekin itzulpen automatiko eraginkorragoa lortzen oten den aztertzeko.

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A series of static and cyclic-static tri-axial compression tests under consolidated-undrained conditions are carried out to study the characteristics of post-cyclic strength of the undisturbed and the remolded samples of marine silty clay. It is found that the post-cyclic monotonic strength decreases if the cyclic strain or pore pressure is over a certain value. The maximum degradation is 10% for undisturbed samples while 70% for remolded ones. The relationship between normalized undrained shear strength and apparent overconsolidation ratio, which is determined by the excess pore pressure induced by cyclic loading, is also established. Static consolidated-undrained tests on overconsolidated remolded samples are also performed. It is proposed that the static consolidated-undrained tests may be substituted for the cyclic-static consolidated-undrained tests if the post-cyclic strength degradation of remolded silty clay is needed to be evaluated simply.

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Instrumental investigations of texture have been performed using texture profile analysis. The following textural parameters have been assessed: hardness, gumminess, chewiness, springiness, cohesiveness and adhesiveness. The fillets of both species have been prepared from deep frozen headed and gutted raw material without fins after frozen storage of 0, 23 and 34 weeks, respectively. Deep freezing of fishes has been performed on board immediately after hauling or after 6 day’s storage in ice. Before texture measurement the raw material has been thawed and the measurement was carriedout on both thawed and microwave-heated fillets. In general, it can be concluded that both fish species are comparable in their texture parameters. The hardness of heated dab has been slightly higher comparing with that one of plaice. All other texture parameters showed a fairly good conformity between both species. While the hardness of dab increased during heating, it was decreasing in plaice. This was the only one significant difference between both fishes during heating. Adhesiveness as well as cohesiveness increased remarkably during heating. Changes effected by ice storage were only slight. Frozen storage, in contrast, caused a significant decrease of adhesiveness measured after heating the fillets of both species.

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The paper examines the pattern of utilization of freshwater fish species in Nigeria. It was observed that although fishermen have a preference for fresh fish sales only 30% of fresh fish captured actually get to the consumers. The rest are preserved by smoke curing (60-65%), salting and sundrying (less than 5%), deep frying and fermentation (about 1%). Constraints to fish utilization were identified which include poor infrastructure, losses of fish and fish products as a result of traditional post harvest technology and socio economic factors. The need for the development of appropriate research to solve the problems of traditional post harvest technology was emphasised

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The findings are presented of a study undertaken to provide baseline information that may be employed to develop a simplified hatchery technique for postlarval feeding of Clarias gariepinus on zooplankton cultured indoors in small aquaria. Three series of experiments were undertaken to identify the type and quantity of organic manure that would produce maximum densities of zooplankton in the shortest time in indoor cultures. Results suggest the possibility of the culture of natural zooplankton populations for use in larval feeding of C. gariepinus fry. Its effective hatchery application would bring about reduction in the unit cost per fingerling and ensure continuous hatchery operations even in the absence of Artemia cysts

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HIGHLIGHTS FOR FY 2006 1. Captured and tagged 475 Gulf sturgeons in five Florida rivers and one bay. 2. Documented Gulf sturgeon marine movement and habitat use in the Gulf of Mexico. 3. Assisted the National Oceanic and Atmospheric Administration (NOAA) with the collection of Gulf sturgeon, implantation of acoustic tags, and monitoring of fish in a study to examine movement patterns and habitat use in Pensacola and Choctawhatchee bays post-Hurricane Ivan. 4. Provided technical assistance to Jon “Bo” Sawyer in completing a study – Summer Resting Areas of the Gulf Sturgeon in the Conecuh/Escambia River System, Alabama-Florida – for acquiring a Degree of Master of Science at Troy University, Alabama. 5. Coordinated tagging and data collection with NOAA observers aboard trawlers while collecting Gulf sturgeon during dredging operations in the coastal Gulf of Mexico. 6. Hosted the 7th Annual Gulf Sturgeon Workshop. 7. Implemented Gulf Striped Bass Restoration Plan by coordinating the 23rd Annual Morone Workshop, leading the technical committee, transporting broodfish, coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system, and evaluating post-stocking success. 8. Continued updating and managing the Freshwater Mussel Survey Database, a Geographic Information System (GIS) database, for over 800 unique sites in the Northeast Gulf (NEG) drainages in Alabama (AL), Georgia (GA), and Florida (FL). 9. Formed a recovery implementation team for listed mussels in the ACF river basin and oversaw grant cooperative agreements for 14 listed and candidate freshwater mussels in the NEG watersheds. 10. Initiated a project in the Apalachicola River to relocate mussels stranded as a result of drought conditions, and calculate river flows at which mussels would be exposed. 11. Initiated a project in Sawhatchee Creek, Georgia to determine the status of threatened and endangered (T&E) freshwater mussels and target restoration projects, population assessments, and potential population augmentation to lead toward recovery of the listed species. 12. Initiated a study to determine the age and growth of the endangered fat threeridge mussel (Amblema neislerii). 13. Provided technical assistance to the Panama City Ecological Services office for a biological opinion on the operations of Jim Woodruff Lock and Dam and its effects on the listed species and designated and proposed critical habitat in the Apalachicola River, Florida. 14. Assisted with a multi-State, inter-agency team to develop a management plan to restore the Alabama shad in the ACF river system. 15. Conducted fishery surveys on Tyndall AFB, Florida and Ft. Benning, Georgia and completed a report with recommendations for future recreational fishery needs. 16. Provided fishery technical assistance to four National Wildlife Refuges (NWR) (i.e., Okefenokee NWR, Banks Lake NWR, St. Vincent NWR, and St. Marks NWR). 17. Initiated an Aquatic Resources and Recreation Fishing Survey on Department of Defense facilities located in Region 4. 18. Identified 130 road-stream crossings on Eglin AFB for rehabilitation and elimination of sediment imputs. 19. Continued the Aquatics Monitoring Program at Eglin AFB to assess techniques that determine current status and sustainability of aquatic habitat and develop a measure to determine quality or degradation of habitat. 20. Assisted Eglin AFB Natural Resource managers in revising the installation’s Integrated Natural Resources Management Plan (INRMP) and its associated component plans. 21. Coordinated recovery efforts for the endangered Okaloosa darter including population/life history surveys, stream restoration, and outreach activities. 22. Initiated a comprehensive status review of the Okaloosa darter with analyses performed to assess available habitat, preferred habitats, range expansions/reductions/fragmentations, population size, and probability of extinction. 23. Assisted the Gulf Coastal Plain Ecosystem Partnership and the Florida Fish and Wildlife Conservation Commission (FWC) under a Memorandum of Agreement to develop conservation strategies, implement monitoring and assessment programs, and secure funds for aquatic management programs in six watersheds in northwest Florida and southeast Alabama. 24. Entered into a cooperative agreement with the U.S. Air Force to encourage the conservation and rehabilitation of natural resources at Hurlburt Field, Florida. 25. Multiple outreach projects were completed to detail aquatic resources’ conservation needs and opportunities; including National Fishing Week, Earth Day, several festivals, and school outreach.

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A long-standing challenge in transition metal catalysis is selective C–C bond coupling of simple feedstocks, such as carbon monoxide, ethylene or propylene, to yield value-added products. This work describes efforts toward selective C–C bond formation using early- and late-transition metals, which may have important implications for the production of fuels and plastics, as well as many other commodity chemicals.

The industrial Fischer-Tropsch (F-T) process converts synthesis gas (syngas, a mixture of CO + H2) into a complex mixture of hydrocarbons and oxygenates. Well-defined homogeneous catalysts for F-T may provide greater product selectivity for fuel-range liquid hydrocarbons compared to traditional heterogeneous catalysts. The first part of this work involved the preparation of late-transition metal complexes for use in syngas conversion. We investigated C–C bond forming reactions via carbene coupling using bis(carbene)platinum(II) compounds, which are models for putative metal–carbene intermediates in F-T chemistry. It was found that C–C bond formation could be induced by either (1) chemical reduction of or (2) exogenous phosphine coordination to the platinum(II) starting complexes. These two mild methods afforded different products, constitutional isomers, suggesting that at least two different mechanisms are possible for C–C bond formation from carbene intermediates. These results are encouraging for the development of a multicomponent homogeneous catalysis system for the generation of higher hydrocarbons.

A second avenue of research focused on the design and synthesis of post-metallocene catalysts for olefin polymerization. The polymerization chemistry of a new class of group 4 complexes supported by asymmetric anilide(pyridine)phenolate (NNO) pincer ligands was explored. Unlike typical early transition metal polymerization catalysts, NNO-ligated catalysts produce nearly regiorandom polypropylene, with as many as 30-40 mol % of insertions being 2,1-inserted (versus 1,2-inserted), compared to <1 mol % in most metallocene systems. A survey of model Ti polymerization catalysts suggests that catalyst modification pathways that could affect regioselectivity, such as C–H activation of the anilide ring, cleavage of the amine R-group, or monomer insertion into metal–ligand bonds are unlikely. A parallel investigation of a Ti–amido(pyridine)phenolate polymerization catalyst, which features a five- rather than a six-membered Ti–N chelate ring, but maintained a dianionic NNO motif, revealed that simply maintaining this motif was not enough to produce regioirregular polypropylene; in fact, these experiments seem to indicate that only an intact anilide(pyridine)phenolate ligated-complex will lead to regioirregular polypropylene. As yet, the underlying causes for the unique regioselectivity of anilide(pyridine)phenolate polymerization catalysts remains unknown. Further exploration of NNO-ligated polymerization catalysts could lead to the controlled synthesis of new types of polymer architectures.

Finally, we investigated the reactivity of a known Ti–phenoxy(imine) (Ti-FI) catalyst that has been shown to be very active for ethylene homotrimerization in an effort to upgrade simple feedstocks to liquid hydrocarbon fuels through co-oligomerization of heavy and light olefins. We demonstrated that the Ti-FI catalyst can homo-oligomerize 1-hexene to C12 and C18 alkenes through olefin dimerization and trimerization, respectively. Future work will include kinetic studies to determine monomer selectivity by investigating the relative rates of insertion of light olefins (e.g., ethylene) vs. higher α-olefins, as well as a more detailed mechanistic study of olefin trimerization. Our ultimate goal is to exploit this catalyst in a multi-catalyst system for conversion of simple alkenes into hydrocarbon fuels.