103 research outputs found

    Chemical Composition of Ambrosia trifida Essential Oil and Phytotoxic Effect on Other Plants

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    This study aimed to identify the main components of an essential oil produced from leaves of Ambrosia trifida and to evaluate its potential allelopathic effect on seed germination and seedling growth of lettuce, watermelon, cucumber and tomato. The essential oil was obtained by hydrodistillation and characterized chemically by gas chromatography (GC) coupled with both mass spectrometry (MS) and flame ionization detector (FID). Total 69 compounds were identified, with limonene (20.7 %), bornyl acetate (15.0 %), borneol (14.7 %) and germacrene D (11.6 %) as the major components. The working solutions of the essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at four concentration levels (0.01, 0.1, 0.5 % and 1 %, v/v). The results obtained showed that increase in essential oil concentration leads to decrease in seed germination, as well as shoot and radical length of lettuce, watermelon, cucumber and tomato. The obtained data revealed a highly significant effect (p lt 0.05) between control and 1 % and 0.5 % oil concentrations in all treatments. The essential oil of A. trifida exhibited more powerful phytotoxic effects on lettuce, watermelon and tomato than on cucumber regarding germination and early seedling growth.This is the peer-reviewed version of the article: Sarić-Krsmanović Marija, Gajić-Umiljendić Jelena, Radivojević Ljiljana, Rajković Miloš, Santrić Ljiljana, Đurović-Pejčev Rada, "Chemical Composition of Ambrosia trifida Essential Oil and Phytotoxic Effect on Other Plants" 17, no. 1 (2020):e1900508, [https://doi.org/10.1002/cbdv.201900508]

    Presence of factors that activate platelet aggregation in mitral stenotic patients' plasma

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    BACKGROUND: Although the association between mitral stenosis (MS) and increased coagulation activity is well recognized, it is unclear whether enhanced coagulation remains localized in the left atrium or whether this represents a systemic problem. To assess systemic coagulation parameters and changes in platelet aggregation, we measured fibrinogen levels and performed in vitro platelet function tests in plasma obtained from mitral stenotic patients' and from healthy control subjects' peripheral venous blood. METHODS: Sixteen newly diagnosed patients with rheumatic MS (Group P) and 16 healthy subjects (Group N) were enrolled in the study. Platelet-equalized plasma samples were evaluated to determine in vitro platelet function, using adenosine diphosphate (ADP), collagen and epinephrine in an automated aggregometer. In vitro platelet function tests in group N were performed twice, with and without plasma obtained from group P. RESULTS: There were no significant differences between the groups with respect to demographic variables. Peripheral venous fibrinogen levels in Group P were not significantly different from those in Group N. Adenosine diphosphate, epinephrine and collagen-induced platelet aggregation ratios were significantly higher in Group P than in Group N. When plasma obtained from Group P was added to Group N subjects' platelets, ADP and collagen-induced, but not epinephrine-induced, aggregation ratios were significantly increased compared to baseline levels in Group N. CONCLUSION: Platelet aggregation is increased in patients with MS, while fibrinogen levels remain similar to controls. We conclude that mitral stenotic patients exhibit increased systemic coagulation activity and that plasma extracted from these patients may contain some transferable factors that activate platelet aggregation

    Market risk of BRIC Eurobonds in the financial crisis period

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    The market risk of returns for BRIC Eurobonds has not been thoroughly analyzed via nonparametric estimation methods. The significance of risk and jumps is examined in a monthly sampling frequency. A detailed comparison upon significance of risk and jumps between BRIC Eurobonds is provided. Comparison concerns risk and jumps during the international financial crisis period: February 2007 up to February 2010. Among the BRIC countries, Chinese Eurobonds are the most significant in terms of both risk and jumps. The most significant estimator is the monthly Yang & Zhang range across the set of BRIC Eurobonds. The shorter the expiry period, the higher is the significance of risk and jumps. This is evident in all BRIC Eurobonds. Risk and jumps estimates are higher for theoretical prices rather than for actual prices according to all risk and jump significance measures

    Risk Factors Associated with Adverse Fetal Outcomes in Pregnancies Affected by Coronavirus Disease 2019 (COVID-19): A Secondary Analysis of the WAPM study on COVID-19

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    To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Mean gestational age at diagnosis was 30.6\ub19.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; p<0.001), birthweight (OR: 1.17, 95% CI 1.09-1.12.7 per 100 g decrease; p=0.012) and maternal ventilatory support, including either need for oxygen or CPAP (OR: 4.12, 95% CI 2.3-7.9; p=0.001) were independently associated with composite adverse fetal outcome. Early gestational age at infection, maternal ventilatory supports and low birthweight are the main determinants of adverse perinatal outcomes in fetuses with maternal COVID-19 infection. Conversely, the risk of vertical transmission seems negligible

    The properties of realized volatility and realized correlation: evidence from the Indian stock market

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    This paper investigates the properties of realized volatility and correlation series in the Indian stock market by employing daily data converting to monthly frequency of five different stock indices from January 2, 2006 to November 30, 2014. Using non-parametric estimation technique the properties examined include normality, long-memory, asymmetries, jumps, and heterogeneity. The realized volatility is a useful technique which provides a relatively accurate measure of volatility based on the actual variance which is beneficial for asset management in particular for non-speculative funds. The results show that realized volatility and correlation series are not normally distributed, with some evidence of persistence. Asymmetries are also evident in both volatilities and correlations. Both jumps and heterogeneity properties are significant; whereas, the former is more significant than the latter. The findings show that properties of volatilities and correlations in Indian stock market have similarities as that show in the stock markets in developed countries such as the stock market in the United States which is more prevalent for speculative business traders

    High Accuracy Mutation Detection in Leukemia on a Selected Panel of Cancer Genes

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    <div><p>With the advent of whole-genome and whole-exome sequencing, high-quality catalogs of recurrently mutated cancer genes are becoming available for many cancer types. Increasing access to sequencing technology, including bench-top sequencers, provide the opportunity to re-sequence a limited set of cancer genes across a patient cohort with limited processing time. Here, we re-sequenced a set of cancer genes in T-cell acute lymphoblastic leukemia (T-ALL) using Nimblegen sequence capture coupled with Roche/454 technology. First, we investigated how a maximal sensitivity and specificity of mutation detection can be achieved through a benchmark study. We tested nine combinations of different mapping and variant-calling methods, varied the variant calling parameters, and compared the predicted mutations with a large independent validation set obtained by capillary re-sequencing. We found that the combination of two mapping algorithms, namely <em>BWA-SW</em> and <em>SSAHA2</em>, coupled with the variant calling algorithm <em>Atlas-SNP2</em> yields the highest sensitivity (95%) and the highest specificity (93%). Next, we applied this analysis pipeline to identify mutations in a set of 58 cancer genes, in a panel of 18 T-ALL cell lines and 15 T-ALL patient samples. We confirmed mutations in known T-ALL drivers, including PHF6, NF1, FBXW7, NOTCH1, KRAS, NRAS, PIK3CA, and PTEN. Interestingly, we also found mutations in several cancer genes that had not been linked to T-ALL before, including JAK3. Finally, we re-sequenced a small set of 39 candidate genes and identified recurrent mutations in TET1, SPRY3 and SPRY4. In conclusion, we established an optimized analysis pipeline for Roche/454 data that can be applied to accurately detect gene mutations in cancer, which led to the identification of several new candidate T-ALL driver mutations.</p> </div

    Patient empowerment in long-term conditions: development and preliminary testing of a new measure

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    BACKGROUND: Patient empowerment is viewed by policy makers and health care practitioners as a mechanism to help patients with long-term conditions better manage their health and achieve better outcomes. However, assessing the role of empowerment is dependent on effective measures of empowerment. Although many measures of empowerment exist, no measure has been developed specifically for patients with long-term conditions in the primary care setting. This study presents preliminary data on the development and validation of such a measure. METHODS: We conducted two empirical studies. Study one was an interview study to understand empowerment from the perspective of patients living with long-term conditions. Qualitative analysis identified dimensions of empowerment, and the qualitative data were used to generate items relating to these dimensions. Study two was a cross-sectional postal study involving patients with different types of long-term conditions recruited from general practices. The survey was conducted to test and validate our new measure of empowerment. Factor analysis and regression were performed to test scale structure, internal consistency and construct validity. RESULTS: Sixteen predominately elderly patients with different types of long-term conditions described empowerment in terms of 5 dimensions (identity, knowledge and understanding, personal control, personal decision-making, and enabling other patients). One hundred and ninety seven survey responses were received from mainly older white females, with relatively low levels of formal education, with the majority retired from paid work. Almost half of the sample reported cardiovascular, joint or diabetes long-term conditions. Factor analysis identified a three factor solution (positive attitude and sense of control, knowledge and confidence in decision making and enabling others), although the structure lacked clarity. A total empowerment score across all items showed acceptable levels of internal consistency and relationships with other measures were generally supportive of its construct validity. CONCLUSION: Initial analyses suggest that the new empowerment measure meets basic psychometric criteria. Reasons concerning the failure to confirm the hypothesized factor structure are discussed alongside further developments of the scale
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