scholarly journals Learning the True Index Level: Index Return Autocorrelation in an REE Auction Market

2001 ◽  
Author(s):  
Patrik Safvenblad
Keyword(s):  
Auction Market ◽  
True Index ◽  
Index Level

Insecticide Residues on 1972 U.S. Auction-Market Tobacco

1975 ◽  
Vol 8 (1) ◽  
Author(s):  
J. J. Domanski ◽  
P. L. Haire ◽  
T.J. Sheets
Keyword(s):  
Detection Limit ◽  
Auction Market ◽  
Insecticide Residues ◽  
Low Detection Limit ◽  
Average Residue ◽  
The Individual ◽  
In Fire

AbstractAverage residue Ievels of DDT + TDE in flue-cured tobacco decreased from 6.1 ppm in 1970 to 0.85 ppm in 1972. DDT + TDE residues in Burley also dropped sharply from previous levels. In 1972 one sample from Kentucky contained 8.17 ppm; all other Burley samples were less than 0.25 ppm. DDT + TDE residues also declined in fire-cured and air-cured types; of these samples Tennessee dark air-cured tobacco contained the highest average residue (3.5 ppm of DDT + TDE). In 1972 over 90 % of the flue-cured samples were positive for toxaphene. Since each of our samples was a composite of tobacco from 10 farmers, we cannot conclude from this result that 90 % of the individual piles contained toxaphene. Significant amounts of toxaphene were found in other types also; for example, 50 % of the 1972 Burley samples had toxaphene concentrations greater than 0.5 ppm. Average endosulfan levels decreased between 1970 and 1972 in flue-cured and Burley tobaccos. However, in all of the dark air and dark fire-cured samples from Tennessee endosulfan residues exceeded 5 ppm. Average endrin residues were at or near the low detection limit in alI samples except fire-cured and dark air-cured tobacco from Tennessee; these averaged 0.26 and 0.17 ppm, respectively.

Assessment of the genotoxic potential of tetrachlorvinphos insecticide by cytokinesis-block micronucleus and sister chromatid exchange assays

2021 ◽  
pp. 096032712110361
Author(s):  
Hayal Cobanoglu ◽  
Akin Cayir
Keyword(s):  
Sister Chromatid ◽  
Sister Chromatid Exchange ◽  
Chromosomal Instability ◽  
Human Peripheral Blood ◽  
Peripheral Blood Lymphocytes ◽  
Proliferation Index ◽  
Dna Damages ◽  
Genotoxic Potential ◽  
Index Level

Tetrachlorvinphos is an organophosphate that is classified as a carcinogen in humans by several authorities. Due to very limited data regarding the genotoxic potential, we aimed to comprehensively investigate in vitro genotoxic potential of tetrachlorvinphos. We performed our study by applying the cytokinesis-block micronucleus cytome and sister chromatid exchange (SCE) assays to human peripheral blood lymphocytes. We evaluated micronucleus (MN) and SCE frequencies and cytokinesis-block proliferation index in both exposed and non-exposed lymphocytes. We also calculated the chromosomal instability level in response to exposure by combining the results of MN and SCE. We found that MN frequency did not increase with exposure to tetrachlorvinphos (0–50 µg/ml). In contrast, we observed that SCE frequencies significantly increased with exposure to ≥5 µg/ml tetrachlorvinphos. Furthermore, exposure to tetrachlorvinphos at concentrations of 50 µg/ml induced a significant increase in chromosomal instability level ( p < 0.05). Cytokinesis-block proliferation index level did not significantly decrease in response to tetrachlorvinphos exposure. Our findings reveal that tetrachlorvinphos resulted in different DNA damages that were measured by two assays. Furthermore, our findings suggested that exposure to tetrachlorvinphos increased chromosomal instability that is a hallmark of many malignancies. We conclude that although tetrachlorvinphos does not significantly increase the MN level, the significant increase of both SCE and CIN frequencies indicates the genotoxic potential of tetrachlorvinphos in human peripheral lymphocytes. Additionally, tetrachlorvinphos is not cytotoxic in the range of tested concentrations.

scholarly journals Longitudinal analysis of antibody decay in convalescent COVID-19 patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Weiming Xia ◽  
Mingfei Li ◽  
Ying Wang ◽  
Lewis E. Kazis ◽  
Kim Berlo ◽  
...  
Keyword(s):  
Immune Response ◽  
Reduction Rate ◽  
Mixed Linear Model ◽  
Decay Rates ◽  
Primary Study ◽  
Igg Antibody ◽  
Blood Samples ◽  
Response Capacity ◽  
Index Level ◽  
Abbott Architect

AbstractDetermining the sustainability of antibodies targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for predicting immune response against the Coronavirus disease 2019 (COVID-19). To quantify the antibody decay rates among the varying levels of anti-nucleocapsid (anti-N) Immunoglobulin G (IgG) in convalescent COVID-19 patients and estimate the length of time they maintained SARS-CoV-2 specific antibodies, we have collected longitudinal blood samples from 943 patients over the course of seven months after their initial detection of SARS-CoV-2 virus by RT-PCR. Anti-N IgG levels were then quantified in these blood samples. The primary study outcome was the comparison of antibody decay rates from convalescent patients with high or low initial levels of antibodies using a mixed linear model. Additional measures include the length of time that patients maintain sustainable levels of anti-N IgG. Antibody quantification of blood samples donated by the same subject multiple times shows a gradual decrease of IgG levels to the cutoff index level of 1.4 signal/cut-off (S/C) on the Abbott Architect SARS-CoV-2 IgG test. In addition, this study shows that antibody reduction rate is dependent on initial IgG levels, and patients with initial IgG levels above 3 S/C show a significant 1.68-fold faster reduction rate compared to those with initial IgG levels below 3 S/C. For a majority of the donors naturally occurring anti-N antibodies were detected above the threshold for only four months after infection with SARS-CoV-2. This study is clinically important for the prediction of immune response capacity in COVID-19 patients.

scholarly journals Tailoring rice varieties to consumer preferences induced by cultural and colonial heritage: Lessons from New Rice for Africa (NERICA) in The Gambia

2021 ◽  
pp. 003072702110197
Author(s):  
Kofi Britwum ◽  
Matty Demont
Keyword(s):  
Consumer Preferences ◽  
Rice Variety ◽  
Import Substitution ◽  
The Gambia ◽  
Rice Varieties ◽  
Auction Market ◽  
Asian Rice ◽  
Market Competitiveness ◽  
New Varieties ◽  
Locally Grown

Rice breeding priorities in Africa often focus on agronomic gains. However, being a net importer of rice, the continent’s varietal replacement success also crucially hinges on new varieties’ market competitiveness vis-à-vis imports. Markets have been profoundly shaped by cultural and colonial heritage. Indigenous preferences for African rice can be traced back to ancient rice domestication and have been subsequently influenced by Asian rice import standards as a result of colonial import substitution policies. New Rice for Africa (NERICA) crosses between African and Asian rice species have the potential to reconcile these dual indigenous/import preferences, but little is known about their market competitiveness. We use auction market data to assess the intrinsic and extrinsic consumer value of NERICA in The Gambia relative to two market standards: branded, Asian rice imports and the most popular locally grown Asian rice variety. We categorize rice consumers into four market segments, based on their heritage as evidenced by their preferences and genealogical lineages. NERICA outperforms both Asian rice standards in terms of market competitiveness, and its value is further reinforced by colonial heritage and labeling, but somewhat weakened by cultural heritage. Consumers were found to pay price premiums for NERICA in the range of 5% to 22% relative to Asian rice imports, with the highest premiums offered by consumers with colonial heritage, representing 86% of the sample. Maintaining and expanding this market will require breeders to incorporate trait mixes that reconcile agronomic gains and consumer preferences induced by cultural and colonial heritage.

scholarly journals Controlling monopoly power in a double‐auction market experiment

2021 ◽  
Author(s):  
Giuseppe Attanasi ◽  
Kene Boun My ◽  
Andrea Guido ◽  
Mathieu Lefebvre
Keyword(s):  
Monopoly Power ◽  
Double Auction ◽  
Auction Market ◽  
Market Experiment

scholarly journals Reoperations Following Lumbar Discectomy Are Associated With Worse Clinical Outcomes and Greater Socioeconomic Burden 3 Years After the Primary Procedure

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Claudius Thomé ◽  
Ali Araghi ◽  
Jason Inzana ◽  
Jonathan Stieber ◽  
Joshua M Ammerman
Keyword(s):  
Back Pain ◽  
Clinical Outcomes ◽  
Lumbar Discectomy ◽  
Control Treatment ◽  
Control Group ◽  
Closure Device ◽  
Number Of Patients ◽  
Patient Reported ◽  
Socioeconomic Burden ◽  
Index Level

Abstract INTRODUCTION Lumbar discectomy patients with large annular defects are at significantly greater risk for symptom recurrence and revision. Previous studies suggest that outcomes following revision surgery are less positive than outcomes from primary discectomy. This analysis aimed to assess the clinical and socioeconomic outcomes associated with postdiscectomy reoperations and the utility of a bone-anchored annular closure device (ACD) for avoiding reoperations. METHODS This study was a retrospective analysis of a prospective randomized controlled trial (RCT). Lumbar discectomy patients with large (>6 mm) annular defects were treated with discectomy alone (Control; n = 278) or discectomy with an ACD (n = 272). Patient-reported outcomes included visual analog scale (VAS) for ipsilateral leg or back pain and Oswestry Disability Index (ODI). At 3 yr, clinical outcomes were available for 75% of the patients. Comparisons of outcomes were made between reoperated (n = 64) and nonreoperated (n = 351) patients, regardless of ACD or Control treatment, at 3 yr following the primary surgery. RESULTS Reoperated patients had significantly worse scores for ODI (24 ± 19 vs 11 ± 13; P < .0001), VAS leg pain (28 ± 30 vs 12 ± 19; P < .0001), and VAS back pain (36 ± 31 vs 17 ± 21; P < .0001). Significantly more nonreoperated patients were working at 3 yr (97% vs 84%; P < .001). Based on Kaplan-Meier analysis, the proportion of subjects experiencing at least 1 index-level reoperation in 3 yr was 11% in the ACD group and 19% in the Control group (P = .007). CONCLUSION Index-level reoperations following lumbar discectomy are associated with worse outcomes and greater socioeconomic burden in patients with large annular defects (>6 mm). These findings are consistent with reports from large registry analyses, including the Spine Patient Outcomes Research Trial (SPORT) and the Swedish National Spine Registry (Swespine). The ACD reduced the number of patients experiencing index-level reoperation by 43%.

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