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The preliminary results obtained provide valuable information to determine the start of grapevine development from available weather data. Despite the first approximation of a cultivars-specific model being made, an experimental approach is currently being conducted to validate the results obtained.
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SCALE DEPENDENCE IN THE RELATIONSHIP BETWEEN TOPOGRAPHIC COMPLEXITY AND INTERTIDAL
COMMUNITY STRUCTUREBenjamin Walker, Corey Garza.
California State University, Monterey Bay, Seaside, CA.
Many factors drive population distribution of species in intertidal communities. Traditionally, it is expected that physical stressors, like desiccation, dictate upper limits for organisms in the intertidal. Biological stressors, like predation and competition, are expected to influence the lower limits for these species. However, small-scale variations in the rocky intertidal may play a significant role in species distribution. Differences in rugosity, relief, and complexity can control habitat suitability for various organisms. In order to isolate the importance of these traits, we scanned 4 rocky intertidal sites within 50 miles of Monterey, California, using a terrestrial laser scanner (TLS). This TLS recorded coordinate and elevation data within each site at a resolution of 5 centimeters. We used geographic information systems to translate this data into high resolution, 3-dimensional maps. We then performed spatial analyses on these maps to quantitatively assess the relationship between topographic complexity and community structure in the rocky intertidal. The results of our study suggest that, not only is there a strong relationship between intertidal topographic complexity and the structure of intertidal communities, this relationship exhibits scale dependence. More broadly, our results suggest that the strength of ecological drivers acting on communities may in part arise from variation in local geological features.
DETERMINATION OF CARBON NANOTUBE UPTAKE, TRANSLOCATION, AND BIOACCUMULATION IN CORN
GROWN IN SOILAmanda Parra, Babina Shrestha, Fahmida Irin, Micah Green, Jaclyn Canas-Carrell.
Texas Tech University, Lubbock, TX.
Carbon nanotube (CNT) applications are expanding in industries such as wastewater treatment, environmental remediation, and agriculture. With their increasing usage, there is a higher possibility of CNTs entering the terrestrial environment, where potential plant uptake and human dietary exposure may occur. This study assessed the uptake and bioaccumulation of different types of CNTs in corn (Zea mays L.) using a newly invented microwave technique that quantitatively determines CNT concentrations in biological samples. The characterization of CNTs was done using thermogravimetric analysis and scanning electron microscopy (SEM). Corn was grown in 10, 100, and 1,000 mg/kg of multiwalled carbon nanotubes (MWNTs) for 40 d in soil. MWNTs were taken up into roots. Concentrations were 10 µg/g in plants exposed for 40 d. MWNTs were also translocated to above ground portions of the plant but at lower concentrations (≤ 6µg/g). Uptake and accumulation studies with single-walled carbon nanotubes (SWNTs) are ongoing. Corn was grown for 40 d in 0, 10, and 100 mg/kg of unfunctionalized, covalently functionalized, and surfactant-stabilized SWNTs in soil. After harvest, roots, stems, and leaves were dried, ground, and analyzed using a microwave technique to determine CNT concentrations. Further studies of CNT uptake, translocation, and accumulation in plants will lead to awareness of potential human exposure and risk assessment.
MERCURY CONCENTRATIONS IN THE TISSUE OF TERRESTRIAL ARTHROPODS FROM THE CENTRAL
CALIFORNIA COASTCruz Ortiz Jr., Peter S. Weiss-Penzias, Russell Flegal.
University of California, Santa Cruz, Santa Cruz, CA.
The aim of this project was to obtain a baseline understanding and investigate the concentration of total mercury (HgT) in the tissue of terrestrial arthropods from the central California coast. Recent findings from this region discovered monomethyl mercury (MMHg) concentrations in fog precipitation to be a factor of 5 higher than those seen in rain water. Mercury concentrations in the tissue of arthropods (Insecta, Malacostraca, and Arachnida) from the central California region are not well documented, so the impact that MMHg deposition in fog has on coastal ecosystems is not yet well understood. Arthropod samples were collected during a 7-month sampling campaign that took place around Monterey Bay between March and October of 2012. Total mercury concentrations in dry weight for the captured specimens ranged from 22 - 188 ng g-1 in Jerusalem crickets (Orthoptera: Stenopelmatidae), 65 - 233 ng g-1 in camel crickets (Orthoptera: Rhaphidophoridae), 25 - 227 ng g-1 in pill bugs (Isopoda: Armadillidiidae), 19 - 563
ng g-1 in ground beetles (Coleoptera: Carabidae), 140 - 441 ng g-1 in variegated meadowhawk dragonflies (Odonata:
Libellulidae), 607 - 657 ng g-1 in pacific spiketail dragonflies (Odonata: Cordulegastridae), and 81 - 1,249 ng g-1 in wolf
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spiders (Araneae: Lycosidae). Preliminary comparison of the data suggests that HgT concentrations are higher in the summer months when fog is frequent. It is hypothesized that coastal fog may be a contributor to this increase of HgT in the tissue of central California arthropods.
DEVELOPMENT OF MOLECULAR BIOMARKERS FOR THE DETECTION OF SUBLETHAL STRESS IN THE
CORAL PORITES LOBATANarrissa P. Spies, Robert Richmond.
Kewalo Marine Laboratory, University of Hawaii at Manoa, Honolulu, HI.
Coral reefs are a vital component of tropical marine ecosystems. Threats to coral reefs are increasing as a result of global climate change and other anthropogenic stressors. A coral stressor can be any event or stimulus that can alter or hinder the ability of a coral to function or reproduce. There is currently no method for detecting the effects of stressors before total or partial coral colony death. The development of molecular biomarkers allows us to examine the expression of gene products associated with stressors such as increased water temperature, heavy metal contamination, soil runoff, and pesticide exposure. With these tools, we are able to detect harmful effects at the molecular level before the manifestation of physical symptoms. Using coral-specific sequences, we have designed Taqman qPCR primers and probes for multiple biomarker genes. We have also identified constitutively expressed genes that can be used for relative quantification of biomarkers at affected sites. Samples were collected at Maunalua Bay,Oahu, Hawaii, known for high levels of runoff and marine pollution, as well as from a reference site. Our data show that biomarker expression levels are differentially expressed between sites and that sublethal stress can be detected in corals using molecular biomarkers.
NITRATE REMOVAL AT THE MOLERA TREAMENT WETLANDGwen Miller, Fred Watson.
California State University, Monterey Bay, Seaside, CA.
The goal of this study is to analyze the long-term effectiveness of nitrate removal within a constructed wetland along the California Central Coast. The wetland used for this analysis was the Molera Treatment Wetland (MTW) located in Castroville, California. The California Central Coast is home to a vast area of agricultural land. Fertilizer runoff from these farms has led to an elevated concentration of nitrate within surface waters; consequently, many of these water bodies are listed as a 303d-impaired water body. Water samples were collected over a 1-year period and analyzed for nitrate and dissolved organic carbon at the inlet and the outlet of the wetland. A total organic carbon analyzer and Lachat were used to measure nutrient samples within the water. Physical parameters such as salinity, temperature, and dissolved oxygen were measured using a Hydrolab water-quality sonde. A tracer test using Rhodamine WT dye was used to determine the residence time at the wetland, allowing for a parcel of water to be traced. Preliminary results indicate that the MTW reduces nitrate concentrations throughout every season. Nitrate removal ranged from an addition of 5.3 mg/L to a removal of 70.6 mg/L of nitrate-N. Preliminary results also indicate that carbon may be limiting denitrification within the wetland. In conclusion, the MTW is a sink for nitrate and can be used as a tool to remove nitrate from agriculturally polluted water. Furthermore, additions of carbon into the system would result in higher rates of nitrate removal.
EQTLS FROM SKELETAL MUSCLE AND ADIPOSE TISSUE ACCOUNT FOR MOST OF THE HERITABILITY OF
TYPE 2 DIABETES ESTIMATED IN MEXICAN AMERICANS, MEXICANS, AND EUROPEANSJason Torres1, Eric Gamazon1, Jennifer Below2, Swapan Das3, Heather Highland4, Esteban Parra5, Adan VelledaresSalagado6, Jorge Escobedo7, Miguel Cruz6, Craig Hanis4, Victoria Prince1, Nancy Cox1 University of Chicago, Chicago, IL, 2University of Washington, Seattle, WA, 3Wake Forest Baptist Medical Center, 1 Winston-Salem, NC, 4University of Texas Health Sciences Center at Houston, Houston, TX, 5University of Toronto, Toronto, ON, CA, 6Hospital de Especialidades, Mexico City, MX, 7Instituto Mexicano del Seguro Social, Mexico City, MX.
Previous studies have shown that top signals from genome-wide association studies (GWAS) on type 2 diabetes (T2D) are enriched for expression quantitative trait loci (eQTLs) identified in skeletal muscle and adipose tissue.
We therefore hypothesized that such eQTLs might account for a disproportionate share of the phenotypic variance in liability to type 2 diabetes (T2D) estimated from all SNPs interrogated through GWAS. To test this hypothesis, we applied genome-wide complex trait analysis (GCTA) to GWAS on T2D from Mexican Americans living in Starr County, TX, (837 cases, 781 controls), and Mexicans from Mexico City (965 cases, 345 controls), as well as to the GWAS on T2D from the WTCCC on subjects from the UK (1,924 cases, 2,938 controls). We estimated the proportion of phenotypic variance attributable to additive effects of all variants interrogated in these GWAS (i.e., chipbased heritability), as well as from a much smaller set of variants identified as eQTLs for muscle or adipose tissue.
Estimates of chip-based heritability were appreciable and statistically significant in all 3 samples (58%, 77%, and 55%, respectively). However, the smaller set of muscle eQTLs accounted for more of the variance in T2D liability (with stronger statistical significance) in the Starr County and Mexico City GWAS than was observed using all SNPs.
Results were similar in all 3 datasets for the set of eQTLs characterized in adipose tissue. These results support our hypothesis that common eQTLs mapped in insulin-responsive tissues account for a substantial portion of the variance in liability to T2D.
IFN-Ɣ IS PROTECTIVE IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS BY ACTIVATING CNSRESIDENT MICROGLIA TO PHAGOCYTOSE NEUROTOXIC MYELIN DEBRISRebecca Sosa, Astrid Cardona, Thomas Forsthuber.
University of Texas at San Antonio, San Antonio, TX.
Multiple sclerosis (MS) is the most common autoimmune demyelinating disease of the central nervous system (CNS), and studies in experimental autoimmune encephalomyelitis (EAE) have shown that neuroantigen-specific CD4+ T cells are the critical mediators of pathology. Mice deficient in the CD4+ Th1 lineage-derived cytokine IFN-ɣ develop more severe disease, implicating that its role in EAE and MS is protective. Using a novel quantitative immunofluorescence (qIF) technique to analyze confocal images of antigen-presenting cells (APCs) in the CNS of wild-type (Wt) and IFN-ɣ-/- or IFN-ɣR-/- C57BL/6 mice, we found this higher disease severity corresponded to decreased myelin Ag uptake by CNS APCs. The novel qIF further showed that the lack of antigen uptake corresponded to a lack of myelin debris cleanup at CNS lesions. Surprisingly, IFN-ɣR-/- APCs from EAE mice or in vitro cultures with exogenous myelin Ag and 2D2 tg T cells produced more IL-17 and GM-CSF in cytokine ELISPOT assays. Flow cytometry for phagocytosis and antigen presentation markers revealed that CD11b+CD45lo microglia were affected most by the absence of IFN-ɣ signaling with a dramatic reduction in activation markers, while CD11b+CD45hi infiltrating macrophages were also less activated. However, CD11c+ dendritic cells (DCs) only experienced a slight decrease in activation markers. These results illuminate IFN-ɣ’s primary protective role via activation of CNS-resident microglia to promote removal of myelin debris, thus facilitating remyelination. Importantly, the activation of DCs to present myelin Ag to encephalitogenic T cells appeared independent of IFN-ɣ signaling and thus represents a potential therapeutic target for slowing MS progression.
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ADENOVIRUS E1A-MEDIATED MODULATION OF HOST CELL TRANSCRIPTIONMiguel Nava, Arnold Berk.
University of California, Los Angeles, Los Angeles, CA.