SynTech Research

Stilwell, KS, United States

SynTech Research

Stilwell, KS, United States
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Ward T.J.,ABC Laboratories | Gaertner K.E.,ABC Laboratories | Gaertner K.E.,SynTech Research | Gorsuch J.W.,Copper Development Association Inc | Call D.J.,Environmental Research and Information Analysts
Bulletin of Environmental Contamination and Toxicology | Year: 2015

Leptocheirus plumulosus was exposed for 28 days to Cu-spiked sediment at mean concentrations ranging from 44.4 to 605 mg Cu/kg dry sediment in a sediment/water test system designed to simulate natural conditions. The NOEC (no observed effect concentration)—LOEC (lowest observed effect concentration) range for the most sensitive endpoint of growth was 199–414 mg Cu/kg sediment. An IC50 for reproduction was estimated at 187 mg Cu/kg sediment. Mean Cu concentrations in pore water (PW) where significant effects were observed were 25.8 and 59.0 µg/L, while their respective concentrations in overlying water (OW) were 22.1 and 28.0 µg Cu/L. Copper concentrations were ≤19.1 and <16.6 µg/L in PW and OW, respectively, at lower exposures where effects were not evident. Concentrations of Cu in marine sediment lower than sediment quality guidelines based on geochemical factors of acid volatile sulfide, organic carbon content (fOC), and sediment grain size (i.e., silt + clay) would appear not to result in adverse effects toward L. plumulosus. © 2015 Springer Science+Business Media New York


Ward T.J.,ABC Laboratories | Gaertner K.E.,ABC Laboratories | Gaertner K.E.,SynTech Research | Gorsuch J.W.,Copper Development Association Inc | Call D.J.,Environmental Research and Information Analysts
Bulletin of Environmental Contamination and Toxicology | Year: 2015

Juvenile marine polychaetes, Neanthes arenaceodentata, were exposed for 28 days to copper (Cu)-spiked sediment at six concentrations ranging from 48.3 to 2380 mg Cu/kg dry sediment, plus control. Survival was reduced (p ≤ 0.05) at concentrations ≥1190 mg Cu/kg. Growth was inhibited at Cu concentrations ≥506 mg Cu/kg. Dose–response relationships yielded LC10 and LC50 estimates of 514 and 1230 mg Cu/kg, respectively. The growth effect EC50 estimate was 409 mg Cu/kg. Ranges for the no observable effect concentration and lowest observable effect concentration were 506–1190 mg Cu/kg for survival, and 230–506 mg Cu/kg for growth. Pore water concentrations of Cu were 38.7–65.8 µg Cu/L in exposures where toxic effects were observed, compared to a range of 15.1–22.4 µg Cu/L in exposures where significant effects were not evident. The results of the study were compared with empirical and mechanistic sediment quality guidelines for the protection of benthic organisms. © 2015 Springer Science+Business Media New York


Lourenco W.R.,French Natural History Museum | Ythier E.,SynTech Research
ZooKeys | Year: 2010

A new species of the endemic Malagasy genus Pseudouroplectes Lourenc ̧o, 1995 (family Buthidae) is described from spiny forests of the southwestern portion of the island. The holotype was obtained in the forests of Ifaty, north of Toliara. With the description of this species, the distributional pattern of this genus is confined to dry forest formations in the south and southwest. A key is proposed to the known species. © W.R. Lourenço, E. Ythier.


Farkas Z.,National Food Chain Safety Office | Horvath Z.,National Food Chain Safety Office | Kerekes K.,National Food Chain Safety Office | Ambrus A.,National Food Chain Safety Office | And 2 more authors.
Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes | Year: 2014

The sampling uncertainty for pesticide residues in carrots, parsley leaves and selected medium size crops was estimated with simple random sampling by applying range statistics. The primary samples taken from treated fields consisted of individual carrots or a handful of parsley leaves. The samples were analysed with QUEChERs extraction method and LCMS/MS detection with practical LOQ of 0.001 mg/kg. The results indicate that the average sampling uncertainties estimated with simple random sampling and range statistics were practically the same. The confidence interval for the estimated sampling uncertainty decreased with the number of replicate samples taken from one lot and the number of lots sampled. The estimated relative ranges of sampling uncertainty are independent from the relative standard deviation of the primary samples. Consequently the conclusions drawn from these experiments are generally applicable. There is no optimum for sample size and number of lots to be tested for estimation of sampling uncertainty. Taking a minimum of 6 replicate samples from at least 8-12 lots is recommended to obtain a relative 95% range of sampling uncertainty within 50%. The cost of sampling/analyses, the consequences of wrong decision should also be taken into account when a sampling plan is prepared. © 2014 Copyright Taylor and Francis Group, LLC.


Lourenco W.R.,French Natural History Museum | Ythier E.,SynTech Research
ZooKeys | Year: 2013

A new species of Tityus, subgenus Atreus (Scorpiones: Buthidae) is described from the Province of Pichincha in the Ecuadorian Andes. Ecuadorian scorpion fauna remains one of the less well studied among those of South America. Nevertheless, some comments are addressed about its remarkable diversity and high level of endemic elements. © Wilson R. Lourenço, Eric Ythier.


Tozzi E.S.,SynTech Research
American Laboratory | Year: 2012

A correct choice of the probe to purchase, probe capabilities, and limitations should be considered with respect to soil type, location of access tubes, and whether or not continuous monitoring is necessary. The Diviner 2000 and EnviroSCAN are less expensive and are not subject to the regulations and permit requirements imposed on the Hydroprobe. However, the Hydroprobe is extremely durable, reliable, and accurate, which is necessary for many research projects. The Neutron Hydroprobe allows for fairly rapid measurements at discrete depths along a 2.44-m profile, but the Diviner 2000's automatic depth and orientation sensing of the capacitance sensor allows swipe-and-go capabilities that significantly decrease sampling time. The Diviner 2000 and EnviroSCAN rely on capacitance sensors that use frequency domain reflectometry. Since the electrical capacitance of the soil is considered part of the sensor's circuit, the dielectric constant of the soil is determined from the charge time of the capacitor.


Holaday A.S.,Texas Tech University | Schwilk D.W.,Texas Tech University | Waring E.F.,Texas Tech University | Guvvala H.,Texas Tech University | And 3 more authors.
Journal of Plant Physiology | Year: 2015

Phalaris arundinacea displaces the slower-growing, native sedge, Carex stricta, where nitrogen availability is high. Our aim was to address whether morphological and physiological traits associated with carbon gain for P. arundinacea and C. stricta responded to nitrogen supply differently and if the species exhibited different degrees of plasticity in these traits. The plants were grown in gravel and provided modified Hoagland's solution containing four nitrogen concentrations from 0.15 to 15mM for 6 to 7 weeks. Supplied nitrogen affected the leaf nitrogen content to the same degree for both species. Increasing supplied nitrogen strongly increased CO2 assimilation (A), photosynthetic nitrogen use efficiency (PNUE), and respiration for P. arundinacea but had only a small effect on these parameters for C. stricta. Relative to growth at 15mM nitrogen, growth at 0.15mM for young leaves decreased carboxylation capacity and efficiency and the capacity for electron transport for P. arundinacea and a larger, stouter Carex species, Carex lacustris, by 53 to 70% but only 20 to 24% for C. stricta. Leaf nitrogen decreased approximately 50% for all species, but vacuolar nitrate did not decrease for P. arundinacea and C. stricta, suggesting that it does not serve as a nitrogen reserve for use during nitrogen deprivation in these species. After 4 months of nitrogen deprivation, P. arundinacea doubled A in 12 days after being supplied 15mM nitrogen, whereas A for C. stricta increased only 22%. We propose that one factor linking P. arundinacea abundance to nitrogen availability involves this species' plastic response of carbon gain to nitrogen supply. C. stricta appears to be adapted to tolerate low nitrogen availability but cannot respond as rapidly and extensively as P. arundinacea when nitrogen supply is high. © 2015 Elsevier GmbH.


A new species of scorpion belonging to the genus Auyantepuia González-Sponga, 1978 (family Chactidae Pocock, 1893) is described on the basis of three specimens collected in a rainforest formation located in Saut Sabbat, South of Mana, French Guiana. This is the tenth species of the Guiano-Amazonian genus Auyantepuia, and the fifth reported from French Guiana. © Eric Ythier.


PubMed | SynTech Research
Type: | Journal: ZooKeys | Year: 2016

A new species of scorpion belonging to the genus Auyantepuia Gonzlez-Sponga, 1978 (family Chactidae Pocock, 1893) is described on the basis of three specimens collected in a rainforest formation located in Saut Sabbat, South of Mana, French Guiana. This is the tenth species of the Guiano-Amazonian genus Auyantepuia, and the fifth reported from French Guiana.


Meyer B.N.,Bayer AG | Lam C.,Bayer AG | Moore S.,Bayer AG | Moore S.,SynTech Research | Jones R.L.,Bayer AG
Journal of Agricultural and Food Chemistry | Year: 2013

Degradation of 11 pyrethroids was measured over approximately 100 days in three sediment/water systems under aerobic and anaerobic conditions at 25 C in the dark. The three California sediments represented a range of textures and organic matter. Test compounds were bifenthrin, cypermethrin, ζ-cypermethrin, cyfluthrin, β-cyfluthrin, deltamethrin, esfenvalerate, fenpropathrin, γ-cyhalothrin, λ-cyhalothrin, and permethrin. A non-standard design was employed to keep conditions essentially the same for all compounds. The test compounds were applied as two test mixtures (six active ingredients per mixture, with bifenthrin common to both) at approximately 50 μg of test compound/kg of sediment (dry weight). Extracts of sediment/water were cleaned up by solid-phase extraction, concentrated, and analyzed by gas chromatography/mass spectrometry (except deltamethrin) against matrix-matched standards, with cyfluthrin-d6 as an internal standard. Deltamethrin was analyzed by liquid chromatography/tandem mass spectrometry using deltamethrin-phenoxy-13C6 as an internal standard. Similar degradation rates of bifenthrin and for related isomeric compounds (e.g., cyfluthrin and β-cyfluthrin) were generally measured in both mixtures for each sediment. First-order half-lives under aerobic conditions ranged from 2.9 to greater than 200 days, with a median value of 18 days. Under anaerobic conditions, the range was from 20 to greater than 200 days, with a median value of 70 days. © 2013 American Chemical Society.

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