505 research outputs found

    The Impacts of Flood, Drought, and Turbidites on Organic Carbon Burial Over the Past 2,000 years in the Santa Barbara Basin, California

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    Climate conditions and instantaneous depositional events can influence the relative contribution of sediments from terrestrial and marine environments and ultimately the quantity and composition of carbon buried in the sediment record. Here, we analyze the elemental, isotopic, and organic geochemical composition of marine sediments to identify terrestrial and marine sources in sediment horizons associated with droughts, turbidites, and floods in the Santa Barbara Basin (SBB), California, during the last 2,000 years. Stable isotopes (ή13C and ή15N) indicate that more terrestrial organic carbon (OC) was deposited during floods relative to background sediment, while bulk C to nitrogen (C/N) ratios remained relatively constant (~10). Long- chain n- alkanes (C27, C29, C31, and C33), characteristic of terrestrial OC, dominated all types of sediment deposition but were 4 times more abundant in flood layers. Marine algae (C15, C17, and C19) and macrophytes (C21 and C23) were also 2 times higher in flood versus background sediments. Turbidites contained twice the terrestrial n- alkanes relative to background sediment. Conversely, drought intervals were only distinguishable from background sediment by their higher proportion of marine algal n- alkanes. Combined, our data indicate that 15% of the total OC buried in SBB over the past 2,000 years was deposited during 11 flood events where the sediment was mostly terrestrially derived, and another 12% of deep sediment OC burial was derived from shelf remobilization during six turbidite events. Relative to twentieth century river runoff, our data suggest that floods result in considerable terrestrial OC burial on the continental margins of California.Key PointsTerrestrial organic carbon is the dominant source of carbon to the SBB with deposition significantly increasing during flood eventsEpisodic flood and turbidite remobilization events were responsible for over 25% of the OC buried in the SBB over the past 2,000 yearsDrought sedimentation had significantly lower sedimentation rates and had an n- alkane composition consistent with increased marine inputsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156217/4/palo20901-sup-0002-2020PA003849-fs01.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156217/3/palo20901_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156217/2/palo20901.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156217/1/palo20901-sup-0003-2020PA003849-fs02.pd

    Manual / Issue 4 / Blue

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    Manual, a journal about art and its making. Blue.The fourth issue. Indigo blue, ultramarine blue, cobalt blue, cerulean blue, zaffre blue, indanthrone blue, phthalo blue, cyan blue, Han blue, French blue, Berlin blue, Prussian blue, Venetian blue, Dresden blue, Tiffany blue, Lanvin blue, Majorelle blue, International Klein Blue, Facebook blue. The names given to different shades of blue speak of plants, minerals, and modern chemistry; exoticism, global trade, and national pride; capitalist branding and pure invention. The fourth issue of Manual is a meditation on blue. From precious substance to controllable algorithm to the wide blue yonder, join us as we leap into the blue. Softcover, 64 pages. Published 2015 by the RISD Museum. Proceeds from RISD Museum publications support the work of the museum. Manual 4 (Blue) contributors include Lawrence Berman, A. Will Brown, Linda Catano, Spencer Fitch, Jessica Helfand, Kate Irvin, Oda van Maanen, Dominic Molon, Maggie Nelson, Ingrid A. Neuman, Margot Nishimura, Karen B. Schloss, Anna Strickland, Louis van Tilborgh, and Elizabeth A. Williams.https://digitalcommons.risd.edu/risdmuseum_journals/1003/thumbnail.jp

    Efecto del formulado comercial de Trichoderma harzianum en semillas de trigo

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    Wheat is one of the most important cereals in the world for human consumption therefore fungal diseases and its control represents a great challenge. This experiment was carried out with the objective of looking for an alternative biological control agent, it was undertaken evaluating the effects of different doses of the commercially formulated Trichoderma harzianum Rifai (1969), fungal base, on quality physiological and sanitary selected wheat seeds. Two different planting methods were employed: in the Blotter test, sowing in seedbed, using a completely random array, applying five treatments with eight repetitions of 50 seeds, reaching a total of 400 seeds, with three different doses of the product (100, 200, 300 mL/100 kg seeds), including the absolute test subject and the chemical composition (Carbendazin + Thiram). The results were subjected to the ANAVA and the Tukey test allowing for a 5 % error margin. The fungal genera identified in the wheat seeds were Rhizopus spp. and Aspergillus flavus, in the control subject, The Rhizopus spp. genus fungi prevailed, while the application of different doses of T. harzianum resulted in a decrease of these colonies. According to the level of control, the three doses of the commercial formula applied were satisfactory, in addition to positively influencing the germination percentage of the seeds in relation to the control and the higher index of growth speed was observed after applying T. harzianum at a 300 mL/100 kg of seed dosage. T. harzianum can be used as a biostimulant in plants with a good antagonistic capability against phytopathogens that cause disease in wheat seeds.El trigo es uno de los cereales de mayor importancia en el mundo para el consumo humano y las enfermedades fĂșngicas y su control representa un gran desafĂ­o. Buscando alternativas de control biolĂłgico, este experimento se realizĂł con el objetivo de evaluar los efectos de diferentes dosis del formulado comercial a base de Trichoderma harzianum Rifai (1969), sobre la calidad fisiolĂłgica y sanitaria de las semillas. Se utilizĂł dos mĂ©todos de siembra: en Blotter test y siembra en almĂĄcigo, empleĂĄndose un diseño completamente al azar, compuesto con cinco tratamientos y ocho repeticiones de 50 semillas, totalizando 400 semillas, con tres diferentes dosis del producto (100, 200, 300 mL/100 kg de semilla), mĂĄs el testigo absoluto y el quĂ­mico (Carbendazin + Thiram). Los resultados fueron sometidos al ANAVA y al test de Tukey al 5 % de error. Los gĂ©neros de hongos identificados en las semillas de trigo fueron Rhizopus spp. y Aspergillus flavus, en el testigo prevalecieron hongos del gĂ©nero Rhizopus spp., mientras las aplicaciones de diferentes dosis de T. harzianum permitieron la disminuciĂłn de sus colonias. SegĂșn el nivel de control, fueron satisfactoria las tres dosis del formulado comercial utilizado, ademĂĄs de influenciar positivamente en el porcentaje de germinaciĂłn de las semillas con relaciĂłn al testigo y el mayor Ă­ndice de velocidad de emergencia fue observado con la aplicaciĂłn de T. harzianum a una dosis de 300 mL/100 kg de semilla. T. harzianum puede ser utilizado como bioestimulantes de las plantas con buena capacidad antagĂłnica contra los fitopatĂłgenos que desarrollan enfermedades en semillas de trigo

    Metabolic profiling of human brain metastases using in vivo proton MR spectroscopy at 3T

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    <p>Abstract</p> <p>Background</p> <p>Metastases to the central nervous system from different primary cancers are an oncologic challenge as the overall prognosis for these patients is generally poor. The incidence of brain metastases varies with type of primary cancer and is probably increasing due to improved therapies of extracranial metastases prolonging patient's overall survival and thereby time for brain metastases to develop. In addition, the greater access to improved neuroimaging techniques can provide earlier diagnosis. The aim of this study was to investigate the feasibility of using proton magnetic resonance spectroscopy (MRS) and multivariate analyses to characterize brain metastases originating from different primary cancers, to assess changes in spectra during radiation treatment and to correlate the spectra to clinical outcome after treatment.</p> <p>Methods</p> <p>Patients (n = 26) with brain metastases were examined using single voxel MRS at a 3T clinical MR system. Five patients were excluded due to poor spectral quality. The spectra were obtained before start (n = 21 patients), immediately after (n = 6 patients) and two months after end of treatment (n = 4 patients). Principal component analysis (PCA) and partial least square regression analysis (PLS) were applied in order to identify clustering of spectra due to origin of metastases and to relate clinical outcome (survival) of the patients to spectral data from the first MR examination.</p> <p>Results</p> <p>The PCA results indicated that brain metastases from primary lung and breast cancer were separated into two clusters, while the metastases from malignant melanomas showed no uniformity. The PLS analysis showed a significant correlation between MR spectral data and survival five months after MRS before start of treatment.</p> <p>Conclusion</p> <p>MRS determined metabolic profiles analysed by PCA and PLS might give valuable clinical information when planning and evaluating the treatment of brain metastases, and also when deciding to terminate further therapies.</p

    Built Environmental Correlates of Walking and Cycling in Dutch Urban Children: Results from the SPACE Study

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    This study examined built environmental correlates of children’s walking and cycling behavior. Four hundred and forty-eight children from 10 Dutch neighborhoods completed a seven-day physical activity diary in which the number of walking and cycling trips for transportation, to school, and for recreation were assessed. The associations between observed built environmental characteristics and children’s walking and cycling behavior were examined with multivariate linear regression analyses. The results showed that built environmental correlates of children’s walking and cycling behavior differ by purpose and by commuting mode implying a behavior-specific approach for interventions and for future, preferably prospective, studies
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