101,868 research outputs found
Exploring the Interplay of Risk Attitude and Organic Food Consumption
No full textThis exploratory study seeks to advance the research on consumers’ preference for organic food eating by investigating the potential association between organic food consumption (OC) frequency and the individual risk attitude. Moreover, inspired by the literature, we investigate also the association between OC and the perceived OC related health improvement (i.e. the avoidance of health risks), subjective trust toward the certification, social norms and several lifestyle factors. Based on a direct survey of 223 Italian college students, a lottery task was used to characterize the individual risk attitude and a simultaneous equation model was estimated. This study marks a beginning by showing a significant relationship between being risk averse and a high organic food eating, offering a hint for future research avenues in the organic domain
Warfarin e PEG-IFN/RBV: sviluppo di test farmacogenetici per la personalizzazione della terapia farmacologica
No full textThe aim of this study was the development and the validation of two pharmacogenetic tests for determination of the personalized dosage of drugs used in clinical settings (Warfarin and PEG-Interferone/Ribavirin) in which genetic testing is necessary and recommended.
Warfarin (Coumadin®) is a widely prescribed anticoagulant used for treatment and prevention of thrombotic disorders. Although highly efficacious, Warfarin’s narrow therapeutic index and wide inter-individual variability in dose response make its dosing difficult.
The standard procedure to define the personalized dose is an iterative process that can take weeks or months and exposes the patients to an increased risk of over- or underanticoagulation and thus to serious side effects like thromboembolism or bleeding. The anticoagulation effect of the Coumadin® drug therapy is influenced by combination of genetic and non-genetic factors , which account for more than half of the inter-individual variation in Warfarin doses required to achieve a therapeutic level of anticoagulation or therapeutic INR (Prothrombin International Normalized Ratio). Since 2011, the FDA requires the product label to include a recommended daily Warfarin dose (mg/day) for therapeutic INR, which is to be based on the genotypes of CYP2C9 and VKORC1. In addition, Genome-Wide Association Studies (GWAS) have confirmed that CYP2C9, VKORC1 and CYP4F2 are the main genetic factors determining the effective Warfarin dose in Caucasians. Therefore, knowledge of the genetic profile provides a means to assess the differential risk of adverse reactions and allows the personalization of the therapy, e.g. lowering the dosage for patients with the alleles CYP2C9 *2 and *3 or that are homozygous for the A-allele (A/A) of the rs9923231 polymorphism in the VKORC1 gene.
The goal of this study was to develop an innovative genotyping system assessing the gene polymorphisms that mainly determine the clinical response to Warfarin. Four polymorphisms were investigated: rs9923231 in the VKORC1 gene, rs1799853 and rs1057910 in the CYP2C9 gene and rs2108622 in the CYP4F2 gene. To evaluate already available systems and decide on the method to be used for the test we performed a benchmarking of the tests present in the market.
The genotyping is performed using a multiplex PCR in combination with a Reverse Line Blot hybridization assay (mPCR/RLB). To ensure specific amplification the test uses the SSP-PCR (Sequence Specific Primer PCR) approach. The high specificity of this PCR method was confirmed by direct sequencing. The test identifies and differentiates SNPs using ASO probes (Allele Specific Oligonucleotide) that recognize the different alleles. The hybrid formed between the amplified target DNA sequence and the complementary probes is detected by a colorimetric reaction using biotin-streptavidin and alkaline phosphatase.
In the first part of the study several parameters like assay temperature, typology of hybridization and washing solutions, incubation time and probe design were analyzed in order to assess their influence on the assay’s performance. Next, the amplification protocol was defined and the conditions of the RLB assay were set up. The kit prototype was then validated on 125 samples, which had been previously genotyped with a standard method (TaqMan® Drug Metabolism Genotyping Assay, Life Technologies), and the analytical sensitivity of the assay was determined. All tested samples were accurately genotyped (100% diagnostic specificity and sensitivity) and the method efficiently worked in a broad range of DNA concentrations. Sensitivity tests demonstrated that the method developed in this study, provided reliable results within a DNA concentration range of 1 ng/reaction to 500 ng/reaction. The shelf life of the reagents was determined to be at least twelve months. In addition, the assay was shown to work on/with the following combinations of probe support materials (a nylon membrane and a nitrocellulose blotting membrane) and PCR master mixes (three commercial available master mixes). A software was developed that automates and facilitates interpretation of the RLB (strip) patterns.
After completion, the system, GENEQUALITY AB WARFARIN TYPE cod. 04-74A-20 (AB ANALITICA), was notified to the Ministero della Salute and was CE IVD marked for commercialization in the European Community.
As this system is the only assay on the market that analyzes the CYP4F2 gene in combination with the CYP2C9 and the VKORC1 gene, it represents the most complete approach for determining the genetic factors influencing Warfarin dosage in Caucasians.
The Hepatitis C virus (HCV) infection is a major health problem with more than 170 million infected individuals worldwide (2-2.5% of the world’s population).
Approximately 30% of the infections are cleared spontaneously, whereas 40% of the patients develop a chronic infection that can lead to cirrhosis, hepatocellular carcinoma and end-stage liver disease. The current standard of care is a combination treatment with pegylated interferon (PEG-INF) and Ribavirin (RBV), but its efficacy and tolerability are limited. Many efforts have been made to identify the factors that influence host resistance to HCV infection and treatment outcome. Several Genome-Wide Association Studies (GWAS) have demonstrated independently that variations in the IL28B (Interleukin 28B) gene are strongly associated with spontaneous clearance of the virus, early viral kinetics and with the varying PEG-INF/RBV therapy response in different populations. Particularly, polymorphism IL28B rs12979860 influences the prospect of recovery from an HCV infection. Patients homozygous for allele rs12979860-C show a two- to threefold higher SVR (Sustained Virological Response) rate compared to persons with a non-CC genotype when undergoing Peg-INF/RBV treatment, have a higher probability of spontaneous clearance of the virus and, during therapy, display a stronger reduction of virus RNA levels, which is reflected in higher RVR (Rapid Virological Response) and EVR (Early Virological Response) rates.
Other studies reported an association of certain functional variants of the ITPA (Inosine Triphosphatase) protein with the reduction of hemoglobin during Peg-INF/RBV therapy. These allelic variants of the ITPA gene decrease the enzymatic activity of ITPA, thus protecting from RBV-induced anemia. The aim was to develop an innovative system to genotype the most significant genetic polymorphisms important for the prediction of treatment response and risk of adverse reactions in patients infected with HCV. Four polymorphisms were investigated in this study: rs12979860 and rs8099917 in the IL28B gene and rs7270101 and rs1127354 in the ITPA gene.
Human genomic DNA was extracted from peripheral blood using an automated system (EZ1, Qiagen). Genotyping of the genetic variants was performed combining multiplex PCR with a Reverse Line Blot hybridization assay (mPCR/RLB). For amplification (PCR) of the target sequences, biotinylated primers were used. The primers were designed and analyzed in silico using bioinformatics alignment tools like “blat” (UCSC) and ClustalW, excluding genomic sequences that contain SNPs, SINEs/LINEs or other repetitive elements and all primer binding sites that show a sequence similarity of more than 95% with other genomic sequences. Due to the fact that a sequence that is highly homologous to the target region in IL28B gene is located on the same chromosome 15.000 bp upstream, the SSP-PCR approach was adopted in order to ensure a high specificity of the amplification. To evaluate the efficacy of the SPP-PCR, the amplification products were analyzed by direct sequencing. Subsequently, the protocol for the multiplex amplification was set up. Probes recognizing the different alleles of each investigated SNP (two ASO, Allele Specific Oligonucleotide, per SNP) were designed and their specificity analyzed under varying experimental conditions. This allowed estimation of the effect of parameters like temperature and time of incubation on the assay performance. The analytical sensitivity of the assay was determined using a range of DNA concentrations between 0.5 ng/µl and 200 ng/µl. The diagnostic specificity of the test was assessed analyzing 160 samples of a known genotype.
The test provided a result within a DNA concentration of 1 ng/reaction to 400 ng/reaction and all tested samples were accurately genotyped. This underlines the reliability and specificity of the assay. The shelf life of the reagents was determined to be at least eight months and the compatibility of the assay with other amplification master mixes or probe supports (membranes) was tested. The system, GENEQUALITY IL28B-ITPA TYPE cod. 04-47A-20 (AB ANALITICA), was notified to the Ministero della Salute and CE IVD marked for commercialization in the European Community.
RLB is a convenient way to identify up to 8 targets in 20 individual specimens simultaneously. It is more flexible and less costly than DNA microarrays while providing the same specificity and sensitivity. The system developed in this study, GENEQUALITY IL28B-ITPA TYPE, code 04-47A-20 (AB ANALITICA), allows analysis of the most important host genetic factors influencing the efficacy of the Peg-INF/RBV therapy and determining the risk of RBV-induced anemia. It is the only assay on the market that analyzes ITPA and IL28B polymorphisms together and therefore represents the most complete approach for determining the genetic constitution in regard to the IL28B and the ITPA gene for personalized management of patients with Hepatitis C.
A genotype-phenotype correlation analysis was performed to evaluate the association between IL28B and ITPA polymorphisms and the therapy outcome in a sub-group of patients (N=52). Genetic analysis of the IL28B polymorphism rs12979860 revealed that 27% of the patients carried the C/C genotype, whereas 56% and 17% carried the C/T and the T/T genotype, respectively. The T/T genotype of the IL28B polymorphism rs8099917 was in 40% of patients, whereas 48% carried T/G and 12% the G/G.
No association was found between variants of the IL28B polymorphisms and SVR rates: 57% of patients with IL28B rs12979860-CC and 52% with IL28B rs8099917-TT achieved SVR and 43% and 48%, respectively, failed to clear the HCV virus.
For analysis of the influence of ITPA, the patients were subdivided into the following three groups: normal ITPase activity (100% ITPA), mild ITPase deficiency (60% ITPA- 60% ITPase activity) and moderate to severe ITPase deficiency (≤30% ITPA, ≤30% ITPase activity). These groups reflected the individual Composite ITPase Deficiency Variable based on the genotypes of the ITPA polymorphisms rs7270101 and rs1127354. Patients with normal ITPase activity were compared to the groups of patients with mild ITPase deficiency and moderate to severe ITPase deficiency by statistical analysis. The results showed that the predicted ITPase deficiency correlated to a reduction of median Hb levels at 4, 12 and 24 weeks of treatment. A statistically significant difference was observed between the groups with normal ITPase activity and moderate to severe ITPase deficiency (≤30% ITPA) at 4 and 24 weeks (Dunnett’s Multiple Comparison Test: T4, p < 0.0001; T24, p < 0.0451). This clearly shows that patients with an at least by 70% decreased ITPase activity are protected from anemia throughout the treatment
Agriculture and Pollinating Insects, No Longer a Choice but a Need: EU Agriculture's Dependence on Pollinators in the 2007-2019 Period
No full textOne of the new objectives laid out by the European Union's Common Agriculture Policy is increasing environmental sustainability. In this paper we compare the degree of average dependence index for each member state (ADIMS) in EU28 from 2007 to 2019 in order to verify the following: (1) whether there was a difference in this index when comparing two CAP periods-(a) from 2007 to 2013 and (b) from 2014 to 2019-and (2) which crops had a larger effect on the ADIMS. The study showed no significant variation in the average ADIMS at EU level between the first (2007-2013) and second (2014-2019) CAP periods. The AIDMS index highlighted three types of EU agriculture: (1) agriculture in Eastern Europe, including Bulgaria, Hungary, Romania and Slovakia, characterized by a high level of ADIMS (10.7-22) due to the widespread cultivation of oil crops as rapeseed and sunflower; (2) Mediterranean agriculture including Portugal, Spain, Italy, Croatia, Greece, Malta, Cyprus and France with lower AIDMS levels (5.3-10.3) given their heterogeneous crop portfolios with different degrees of dependence on animal pollination (almond, soy, rapeseed, sunflower and tomatoes) and (3) continental agriculture including Germany, Austria, Slovenia, Poland, the Czech Republic, Baltic countries, Benelux, Finland, Sweden and Ireland, which are characterized by the lowest ADIMS level (0.7-10.6) due to the widespread cultivation of cereals (anemophily and self-pollination) which increase the denominator of the index. The study suggests that a sustainable management of the agroecosystem will be possible in the future only if CAP considers pollinators' requirements by quantifying the timing and spatial food availability from cultivated and uncultivated areas
Agriculture and Pollinating Insects, No Longer a Choice but a Need: EU Agriculture’s Dependence on Pollinators in the 2007–2019 Period
No full textOne of the new objectives laid out by the European Union's Common Agriculture Policy is increasing environmental sustainability. In this paper we compare the degree of average dependence index for each member state (ADIMS) in EU28 from 2007 to 2019 in order to verify the following: (1) whether there was a difference in this index when comparing two CAP periods-(a) from 2007 to 2013 and (b) from 2014 to 2019-and (2) which crops had a larger effect on the ADIMS. The study showed no significant variation in the average ADIMS at EU level between the first (2007-2013) and second (2014-2019) CAP periods. The AIDMS index highlighted three types of EU agriculture: (1) agriculture in Eastern Europe, including Bulgaria, Hungary, Romania and Slovakia, characterized by a high level of ADIMS (10.7-22) due to the widespread cultivation of oil crops as rapeseed and sunflower; (2) Mediterranean agriculture including Portugal, Spain, Italy, Croatia, Greece, Malta, Cyprus and France with lower AIDMS levels (5.3-10.3) given their heterogeneous crop portfolios with different degrees of dependence on animal pollination (almond, soy, rapeseed, sunflower and tomatoes) and (3) continental agriculture including Germany, Austria, Slovenia, Poland, the Czech Republic, Baltic countries, Benelux, Finland, Sweden and Ireland, which are characterized by the lowest ADIMS level (0.7-10.6) due to the widespread cultivation of cereals (anemophily and self-pollination) which increase the denominator of the index. The study suggests that a sustainable management of the agroecosystem will be possible in the future only if CAP considers pollinators' requirements by quantifying the timing and spatial food availability from cultivated and uncultivated areas
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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3346: Samuel G. Freedman, author, 2013
No full textPhotograph of author Samuel G. Freedman, at NT Daily Slash meeting in the Mayborn School of Journalism at UNT
The Right to Strike under the United States Constitution: Theory, Practice, and Possible Implications for Canada
No full textAnswering critics of the Canadian Supreme Court's judgment in B.C. Health, the author argues that the Court laid the foundation for a principled and durable doctrine protecting constitutional labour rights, one that goes directly to the heart of the matter — the inequality of workers’ power in the employment relation. In the author’s view, two paths could lead from B.C. Health to the recognition of Charter protec- tion for a right to strike: one that treats the right as an accessory to col- lective bargaining, and one that upholds the right directly on the basis of the Charter values of equality and participation. The author supports the latter approach, contending that constitutional rights should be defined in relation to fundamental values, in a way that is not contingent on time-bound or fact-sensitive assessments about the role of strikes within a particular collective bargaining regime. Although a Charter right to strike may involve the courts in difficult choices about when to defer to legislative policy decisions, and courts may lack the institutional capac- ity to deal effectively with labour law issues, the author points out that judges can look to ILO standards for expert guidance. Noting that the U.S. experience in this area might be of considerable use to Canadians, the author concludes by providing an overview of American case law concerning a constitutional right to strike.Peer reviewe
G-Rank: Unsupervised Continuous Learn-to-Rank for Edge Devices in a P2P Network
No full textRanking algorithms in traditional search engines are powered by enormous training data sets that are meticulously engineered and curated by a centralized entity. Decentralized peer-to-peer (p2p) networks such as torrenting applications and Web3 protocols deliberately eschew centralized databases and computational architectures when designing services and features. As such, robust search-and-rank algorithms designed for such domains must be engineered specifically for decentralized networks, and must be lightweight enough to operate on consumer-grade personal devices such as a smartphone or laptop computer. We introduce G-Rank, an unsupervised ranking algorithm designed exclusively for decentralized networks. We demonstrate that accurate, relevant ranking results can be achieved in fully decentralized networks without any centralized data aggregation, feature engineering, or model training. Furthermore, we show that such results are obtainable with minimal data preprocessing and computational overhead, and can still return highly relevant results even when a user’s device is disconnected from the network. G-Rank is highly modular in design, is not limited to categorical data, and can be implemented in a variety of domains with minimal modification. The results herein show that unsupervised ranking models designed for decentralized p2p networks are not only viable, but worthy of further research.https://github.com/awrgold/G-RankComputer Scienc
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