Deposition and Retention of Chlorothalonil Applied to Peanut Foliage: Effects of Application Methods, Fungicide Formulations and Oil Additives1

1990 ◽  
Vol 17 (2) ◽  
pp. 80-84 ◽  
Author(s):  
T. B. Brenneman ◽  
H. R. Sumner ◽  
G. W. Harrison
Keyword(s):  
Gas Chromatography ◽  
Half Life ◽  
Plant Canopy ◽  
Arachis Hypogaea L ◽  
Center Pivot ◽  
Residue Levels ◽  
The Mean ◽  
Application Methods ◽  
Initial Deposition ◽  
Petroleum Oil

Abstract Deposition and retention of chlorothalonil (CTL) on peanut (Arachis hypogaea L.) foliage was evaluated by surface-stripping leaf discs with toluene and determining the CTL concentration via gas chromatography. CTL was applied at 1.25 kg/ha via ground sprays, a center pivot-mounted underslung boom, or chemigation in 0.12, 1.7, or 17.8 kL of water/ha, respectively. Ground sprays resulted in the highest concentrations of CTL on peanut leaves followed by the underslung boom and chemigation, respectively. Residue levels were lower with the higher volume applications but were more uniformly distributed throughout the plant canopy. Deposition of chemigated CTL applied as Bravo 500(R), Bravo 720(R), or Bravo 720(R) plus either an emulsifiable vegetable oil (SoyOil 937(R) or a nonemulsifiable petroleum oil (UN Sunspray oil(R)) was also evaluated. Results of residue sampling at 0, 5, 9 and 14 days after treatment indicated that addition of either oil to Bravo 720(R) resulted in the highest initial deposition of fungicide followed by Bravo 500(R) and Bravo 720(R) alone, respectively. However, the half-life of CTL applied as Bravo 720(R) plus either oil was reduced as compared to the half-life for either Bravo 720(R) alone or Bravo 500(R). By day 14, concentrations of CTL had decreased by more than 93% in all treatments. The mean half-life of CTL for all treatments was 3.8, 4.8 and 4.8 days in the top, middle and bottom canopy layers, respectively.

scholarly journals Residual behaviour of imidacloprid in the country bean growing soil

2019 ◽  
Vol 44 (1) ◽  
pp. 89-101
Author(s):  
H Rahman ◽  
T Akter ◽  
HK Mishu ◽  
RU Miah ◽  
MS Alam
Keyword(s):  
Risk Assessment ◽  
Gas Chromatography ◽  
Half Life ◽  
Target Site ◽  
Determination Limit ◽  
Plant Canopy ◽  
Quechers Method ◽  
Soil System ◽  
Degradation Pattern ◽  
Preharvest Interval

The assessment of residual behavior of imidacloprid (Admire 20SL) in the soil of country bean agroecosystem and its risk assessment for consumption was studied. QuEChERS method was used for the extraction and clean-up of samples and the residues of imidacloprid was estimated using Gas Chromatography. The dissipation studies in the soil system were carried out by application of imidacloprid at five different dosages i.e. 100, 200, 300, 400, and 500 g a.i. ha-1. Average initial deposits of imidacloprid were found to be 0.99, 1.33, 1.62, 1.83 and 2.20 mg.kg-1. The residues reached below determination limit (BDL) of 0.01 mg kg-1 in 9 days for recommended dose and 12 days for remaining higher dosages. Half-life (T1/2)) of imidacloprid in the soil was observed to be 1.88, 1.74, 1.73, 1.56 and 1.52 days for 100, 200, 300, 400, and 500 g a.i. ha-1, respectively. The chemodynamics study of imidacloprid spray indicated that only 27.20 -28.40% sprays were deposited to the target site (plant canopy) and 71.60-72.80% were lost to non-target site such as soil and air. The drift of imidacloprid to soil (39.47-40.20%) was higher than the air (32.13-32.60%). Based on degradation pattern and maximum, the recommended preharvest interval (PHI) might be eight 9 days and a waiting period of two days might be suggested for reapplication of the imidacloprid in country bean agroecosystem. Bangladesh J. Agril. Res. 44(1): 89-101, March 2019

Plasma Thrombospondin as an Indicator of Intravascular Platelet Activation in Patients with Vasculitis

1987 ◽  
Vol 58 (03) ◽  
pp. 850-852 ◽  
Author(s):  
M B McCrohan ◽  
S W Huang ◽  
J W Sleasman ◽  
P A Klein ◽  
K J Kao
Keyword(s):  
Platelet Activation ◽  
Plasma Levels ◽  
Half Life ◽  
Degradation Products ◽  
Plasma Concentrations ◽  
Primary Source ◽  
Positive Correlation ◽  
Activation Marker ◽  
Fibrin Degradation Products ◽  
The Mean

SummaryThe use of plasma thrombospondin (TSP) concentration was investigated as an indicator of intravascular platelet activation. Patients (n = 20) with diseases that have known vasculitis were included in the study. The range and the mean of plasma TSP concentrations of patients with vasculitis were 117 ng/ml to 6500 ng/ml and 791±1412 ng/ml (mean ± SD); the range and the mean of plasma TSP concentrations of control individuals (n = 33) were 13 ng/ml to 137 ng/ml and 59±29 ng/ml. When plasma TSP concentrations were correlated with plasma concentrations of another platelet activation marker, β-thromboglobulin (P-TG), it was found that the TSP concentration inei eased exponentially as the plasma β-TG level rose. A positive correlation between plasma levels of plasma TSP and serum fibrin degradation products was also observed. The results suggest that platelets are the primary source of plasma TSP in patients with various vasculitis and that plasma TSP can be a better indicator than β-TG to assess intravascular platelet activation due to its longer circulation half life.

scholarly journals Comparing plastic syringes and disposable columns to extract n-alkanes in forage and concentrate feeds

2010 ◽  
Vol 40 (8) ◽  
pp. 1844-1847 ◽  
Author(s):  
Dimas Estrasulas de Oliveira ◽  
Luis Orlindo Tedeschi
Keyword(s):  
Gas Chromatography ◽  
Linear Regression ◽  
Mean Square Error ◽  
Carbon Chain ◽  
Carbon Chain Length ◽  
Square Root ◽  
Mean Square ◽  
Alternative Material ◽  
The Mean ◽  
Disposable Plastic

Saturated aliphatic hydrocarbons (n-alkanes) were extracted from feed, orts, and bovine fecal samples using disposable, plastic 5mL-syringes as an alternative material to disposable columns, which are normally used in the liquid-solid extraction phase of n-alkanes. For both methods, the n-alkane extracts (carbon chain length between 31 and 36 atoms) were identified using gas chromatography. The linear regression between methods were: 1) feces: column Alkane=2.63+0.92×syringeAlkane [r²=0.94, square root of the mean square error (RMSE)=13.7mg kg-1, n=30] from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively; 2) feeds: column Alkane=0.36+1.12×syringeAlkane (r²=0.85, RMSE=1.9mg kg-1, n=21) from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively; 3) orts: column Alkane=0.49+0.92×syringeAlkane (r²=0.98, RMSE=1.2mg kg-1, n=15) from which the intercept and the slope did not simultaneously differ from zero and unity (P>0.05), respectively. Materials with low concentration of n-alkanes may affect the values obtained in both methods. These results suggested that disposable plastic syringes might be a viable alternative to columns thus, reducing analytical costs.

Impairment of Antipyrine Metabolism in Urinary Tract Cancer

1983 ◽  
Vol 69 (3) ◽  
pp. 221-222 ◽  
Author(s):  
Maura Ludovici ◽  
Piero Dolara ◽  
Alfiero Costantini ◽  
Guido Barbagli ◽  
Anna Calzolai ◽  
...  
Keyword(s):  
Urinary Tract ◽  
Half Life ◽  
Clinical Parameters ◽  
Tract Cancer ◽  
Patients With Cancer ◽  
Control Subjects ◽  
Antipyrine Metabolism ◽  
Urinary Tract Cancer ◽  
The Mean ◽  
Age And Sex

The metabolism of antipyrine was studied in 13 patients with cancer and bladder papillomas and in 11 control subjects, matched for interfering factors like smoking, diet, age and sex. The mean antipyrine half-life was significantly longer in patients with urinary tract cancer (14.7 ± 1.32 h SE) than in control subjects (11 ± 0.55 h SE) (P < 0.025); other clinical parameters did not vary.

A Study of the Metabolism of Fibrinogen after Surgical Operations

1971 ◽  
Vol 41 (2) ◽  
pp. 141-152 ◽  
Author(s):  
J. A. Hickman
Keyword(s):  
Venous Thrombosis ◽  
Disseminated Intravascular Coagulation ◽  
Half Life ◽  
Plasma Fibrinogen ◽  
Intravascular Coagulation ◽  
Plasma Loss ◽  
The Mean ◽  
Chronic Disorders ◽  
Contrast Group ◽  
Surgical Operations

1. The turnover of fibrinogen was studied in twenty-eight patients after moderate and major surgical operations and in a contrast group of thirteen patients suffering from miscellaneous chronic disorders. 2. After operation the mean biological half-life of fibrinogen was 60.1 h (SD 16.4) and the mean plasma loss of fibrinogen was 40.1% (SD 12.6) of the intravascular fibrinogen pool each 24 h. In the contrast group, respective values of 96.2 h (SD 13.1) and 22.5% (SD 2.0) were obtained, which are in agreement with published values for the normal catabolism of fibrinogen. 3. When the post-operative increase in the plasma fibrinogen pool was taken into account, a massive increase in the absolute plasma loss of fibrinogen was observed with values approaching those reported for albumin turnover. 4. Possible sites of loss and the relevance of this investigation to the detection of disseminated intravascular coagulation and venous thrombosis are discussed.

Partial resistance of Southern Runner, Arachis hypogaea, to stem rot caused by Sclerotium rolfsii1

1990 ◽  
Vol 17 (2) ◽  
pp. 65-67 ◽  
Author(s):  
T. B. Brenneman ◽  
W. D. Branch ◽  
A. S. Csinos
Keyword(s):  
Arachis Hypogaea ◽  
Disease Incidence ◽  
Sclerotium Rolfsii ◽  
Field Tests ◽  
Stem Rot ◽  
Pod Yield ◽  
Industry Standard ◽  
Arachis Hypogaea L ◽  
The Mean ◽  
Disease Loci

Abstract The susceptibility of 16 peanut (Arachis hypogaea L.) genotypes (eight Virginia and eight runner types) to southern stem rot (Sclerotium rolfsii Sacc.) was evaluated in field tests over three years. Mean disease incidence for all cultivars was 10.0, 15.4 and 16.4 disease loci per 12.2 m row and average yields were 3488, 2826 and 3569 kg/ha in 1986, 1987 and 1988, respectively. Disease incidence averaged 14.3 disease loci per 12.2 m of row for both market types. The mean yield for the eight Virginia types was 3287 kg/ha versus 3214 for the eight runner types. Culitvars within market types varied significantly in disease incidence and pod yield. Of the Virginia types, NC 6 and Florigiant were the most susceptible with NC 9, VA 81B and Early Bunch being the most resistant. Incidence of stem rot in runner cultivars was high except for Southern Runner and Langley which had about 50% less disease than the most susceptible entries. There was a highly significant correlation (P≤0.01) between yields and disease incidence all three years. Overall, Southern Runner had the lowest disease incidence and highest pod yield of any cultivar. Compared to Florunner, the current industry standard for runner types, Southern Runner had about 50% less disease and yields were 1346 kg/ha higher.

scholarly journals hCGbeta core fragment is a metabolite of hCG: evidence from infusion of recombinant hCG

2000 ◽  
Vol 164 (3) ◽  
pp. 299-305 ◽  
Author(s):  
RJ Norman ◽  
MM Buchholz ◽  
AA Somogyi ◽  
F Amato
Keyword(s):  
Renal Clearance ◽  
Clearance Rate ◽  
Half Life ◽  
Urine Samples ◽  
Molar Ratio ◽  
Gel Chromatography ◽  
Core Fragment ◽  
Terminal Half Life ◽  
Intact Molecule ◽  
The Mean

The availability of recombinant human chorionic gonadotrophin (r-hCG) has allowed us to measure its metabolic and renal clearance rates and to study the origin of the beta core fragment of hCG (hCGbetacf). Serum and urine samples were collected from six subjects, after an intravenous injection of 2 mg (equivalent to 44 000 IU Urinary hCG) r-hCG, and assayed for hCG and the beta subunit (hCGbeta). Urine from four of the subjects was also subjected to gel chromatography and assayed for hCGbetacf and hCG. r-hCG, administered as an intravenous dose, was distributed, initially in a volume of 3.4+/-0.7 l (mean+/-s.d.) and then in 6.5+/-1.15 l at steady-state. The disappearance of r-hCG from serum was bi-exponential, with an initial half-life of 4.5+/-0.7 h and a terminal half-life of 29.0+/-4.6 h. The mean residence time was 28. 6+/- 3.6 h and the total systemic clearance rate of r-hCG was 226+/-18 ml/h. The renal clearance rate was 28.75+/-6.2 ml/h (mean+/-s.d). hCGbetacf was detected in all urine samples collected at 6 h intervals. Over the 138 h period of urine collection, 12.9% (range 10.1-17.3% ) of r-hCG injected was recovered as the intact molecule and 1.7% (range 0.8-2.9%) was recovered as the hCGbetacf, in 4 subjects. The molar ratio of hCGbetacf to hCG in urine increased from 3.1+/-1.7%, on day 1, to 76+/-34.3% (mean+/-s.e.m.) on day 5, after r-hCG infusion, suggesting that hCGbetacf is a metabolic product of the infused r-hCG.

scholarly journals Proposed Serum Cholesterol Reference Measurement Procedure by Gas Chromatography–Isotope Dilution Mass Spectrometry

2011 ◽  
Vol 57 (4) ◽  
pp. 614-622 ◽  
Author(s):  
Selvin H Edwards ◽  
Mary M Kimberly ◽  
Susan D Pyatt ◽  
Shelton L Stribling ◽  
Kara D Dobbin ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Serum Cholesterol ◽  
Isotope Dilution ◽  
Isotope Dilution Mass Spectrometry ◽  
Measurement Procedure ◽  
Standard Reference Materials ◽  
Reference Measurement ◽  
Reference Measurement Procedure ◽  
The Mean

BACKGROUND Our purpose was to establish a mass spectrometry reference measurement procedure (RMP) for cholesterol to use in the CDC's standardization programs. We explored a gas chromatography–isotope dilution mass spectrometry (GC-IDMS) procedure using a multilevel standard calibration curve to quantify samples with varying cholesterol concentrations. METHODS We calibrated the mass spectrometry instrument by isotope dilution with a pure primary standard reference material and an isotopically enriched cholesterol analog as the internal standard (IS). We diluted the serum samples with Tris-HCl buffer (pH 7.4, 0.05 mol/L, 0.25% Triton X-100) before analysis. We used 17 serum pools, 10 native samples, and 2 standard reference materials (SRMs). We compared the GC-IDMS measurements with the CDC's modified Abell–Levy–Brodie–Kendall (AK) RMP measurements and assessed method accuracy by analyzing 2 SRMs. We evaluated the procedure for lack of interference by analyzing serum spiked with a mixture of 7 sterols. RESULTS The mean percent bias between the AK and the GC-IDMS RMP was 1.6% for all samples examined. The mean percent bias from NIST's RMP was 0.5% for the SRMs. The total %CVs for SRM 1951b levels I and II were 0.61 and 0.73%, respectively. We found that none of the sterols investigated interfered with the cholesterol measurement. CONCLUSIONS The low imprecision, linear response, lack of interferences, and acceptable bias vs the NIST primary RMP qualifies this procedure as an RMP for determining serum cholesterol. The CDC will adopt and implement this GC-IDMS procedure for cholesterol standardization.

Chemical Composition and Repellency Effect of Ferulago Angulate Plant Against Malaria Vector, Anopheles Stephensi

2020 ◽  
Author(s):  
Masoumeh Pirmohammadi ◽  
Mansoureh Shayeghi ◽  
Mohammad Reza Abai ◽  
Hassan Vatandoost ◽  
Sara Rahimi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Chemical Composition ◽  
Malaria Vector ◽  
Anopheles Stephensi ◽  
Control Measures ◽  
Gas Chromatography Mass Spectrometry ◽  
Anopheles Mosquitoes ◽  
Protection Time ◽  
The Mean

Abstract BackgroundMalaria is a health problem globally. There are several vector control measures. Using repellent to protect human from biting of vectors is one of the best ways. The aim of this study is to evaluate the efficacy of plant against biting of malaria vector, An.stephensi under laboratory conditions.MethodsChemical constituents of Ferulago angulate plant were determined by using gas chromatography-mass spectrometry. Efficacy and the protection time of plant were evaluated on Anopheles stephensi . ResultsA total of 40 compounds were identified in plant. Flourensiadiol (17.4%) dehydro-sabina keton (13.3%), β-maaliene (8.8%) was the highest in the plant. The mean assessed protection time and efficacy for plant was 60 and 100 minutes respectively. ED50 and ED90 values for this plant were 18.12 and 93.19 µl /cm2 respectively.ConclusionResults showed that plant has an acceptable protection time, therefore, this plant could be considered as a good herbal repellent against anopheles mosquitoes.

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