182 research outputs found
Interests, trust and security in US-Jordanian nuclear relations
This article explores the relationship between Jordan and the United States (US) in the field of nuclear energy cooperation. Since 2010 the Jordanian government has accelerated its plans for a nuclear energy program and has engaged with multiple partners around the world in order to agree terms for cooperation in technology exchange, monitoring, and the construction of infrastructure. Bilateral negotiations between the US and Jordan for a "123" nuclear cooperation agreement were underway by early 2008, but were suspended in 2011 without an agreement being reached. Jordanian nuclear energy policy has been spurred by energy security considerations (as it currently imports 97 percent of its energy needs) and the discovery of up to 120,000 tonnes of uranium ore in Jordan. At the same time, the US is primarily interested in management of nuclear technology proliferation. This work considers the perceptions of self and other in Jordanian and US policymaking in order to understand why bilateral cooperation has not materialized and what this means for nuclear proliferation in Jordan. This study finds that the US–Jordanian negotiations have been impeded by contradictory objectives and perceptions, and a "123" agreement is not likely in the short to medium term, but that development of Jordan’s nuclear energy program will likely continue regardless
In vitro and in vivo anthelmintic efficacy of condensed tannins extracted from the seeds of alfalfa (Medicago sativa L.) against Haemonchus contortus infection
This study was designed to examine in vitro and in vivo anthelmintic efficacy of condensed tannins (CT) extracted from seeds of Medicago sativa on Haemonchus contortus in sheep. CT's in vitro anthelmintic effect was assessed at a 300 μg/ml concentration compared with albendazole (reference drug) at 10 μg/ml. The results showed that CT had a nematocidal effect on H. contortus, and the cuticle of the adult worm appeared to be its initial target. For the in vivo experiment, nine 3-month-old helminths-free lambs were distributed into three groups. Group 1 (n=3) was challenged only as infected untreated controls; Group 2 (n=3) was treated with condensed tannin, and Group 3 (n=3) was treated with albendazole. Fecal and blood samples were collected every 3 days until the end of the experiment; for fecal egg count (FEC) and anti- H. contortus IgG titers determination, respectively. The lambs treated with the CT in G2 exhibited a pronounced decrease of mean FEC with great FECR% detected from the first-week post-treatment (PT) until the end of the experiment compared with G1 animals. The antibody levels gradually increased in G2 following the 2nd dose of CT treatment compared to other groups. A brilliant consistent relation between the elevation of IgG response and reduction of FEC was observed following the second booster dosing of the CT in G2. In conclusion, the CT evoked strongly in vitro and in vivo anthelmintic activity against H. contortus and could be used as a natural alternative treatment of high potency against haemonchosis in sheep
Novel mutation in the CHST6 gene causes macular corneal dystrophy in a black South African family
Repeatability of Foveal Measurements Using Spectralis Optical Coherence Tomography Segmentation Software
PURPOSE: To investigate repeatability and reproducibility of thickness of eight individual retinal layers at axial and lateral foveal locations, as well as foveal width, measured from Spectralis spectral domain optical coherence tomography (SD-OCT) scans using newly available retinal layer segmentation software.
METHODS: High-resolution SD-OCT scans were acquired for 40 eyes of 40 young healthy volunteers. Two scans were obtained in a single visit for each participant. Using new Spectralis segmentation software, two investigators independently obtained thickness of each of eight individual retinal layers at 0°, 2° and 5° eccentricities nasal and temporal to foveal centre, as well as foveal width measurements. Bland-Altman Coefficient of Repeatability (CoR) was calculated for inter-investigator and inter-scan agreement of all retinal measurements. Spearman's ρ indicated correlation of manually located central retinal thickness (RT0) with automated minimum foveal thickness (MFT) measurements. In addition, we investigated nasal-temporal symmetry of individual retinal layer thickness within the foveal pit.
RESULTS: Inter-scan CoR values ranged from 3.1μm for axial retinal nerve fibre layer thickness to 15.0μm for the ganglion cell layer at 5° eccentricity. Mean foveal width was 2550μm ± 322μm with a CoR of 13μm for inter-investigator and 40μm for inter-scan agreement. Correlation of RT0 and MFT was very good (ρ = 0.97, P 0.05); however this symmetry could not be found at 5° eccentricity.
CONCLUSIONS: We demonstrate excellent repeatability and reproducibility of each of eight individual retinal layer thickness measurements within the fovea as well as foveal width using Spectralis SD-OCT segmentation software in a young, healthy cohort. Thickness of all individual retinal layers were symmetrical at 2°, but not at 5° eccentricity away from the fovea
Mifepristone Increases the Cytotoxicity of Uterine Natural Killer Cells by Acting as a Glucocorticoid Antagonist via ERK Activation
Background: Mifepristone (RU486), a potent antagonist of progesterone and glucocorticoids, is involved in immune regulation. Our previous studies demonstrated that mifepristone directly augments the cytotoxicity of human uterine natural killer (uNK) cells. However, the mechanism responsible for this increase in cytotoxicity is not known. Here, we explored whether the increased cytotoxicity in uNK cells produced by mifepristone is due to either anti-progesterone or anti-glucocorticoid activity, and also investigated relevant changes in the mitogen-activated protein kinase (MAPK) pathway. Methodology/Principal Findings: Uterine NK cells were isolated from decidual samples and incubated with different concentrations of progesterone, cortisol, or mifepristone. The cytotoxicity and perforin expression of uNK cells were detected by mitochondrial lactate dehydrogenase-based MTS staining and flow cytometry assays, respectively. Phosphorylation of components of the MAPK signaling pathway was detected by Western blot. Cortisol attenuated uNK cell-mediated cytotoxicity in a concentration-dependent manner whereas progesterone had no effect. Mifepristone alone increased the cytotoxicity and perforin expression of uNK cells; these effects were blocked by cortisol. Furthermore, mifepristone increased the phosphorylation of ERK1/2 in a cortisol-reversible manner. Specific ERK1/2 inhibitor PD98059 or U0126 blocked cortisol- and mifepristone-induced responses in uNK cells
Macular thickness measurements in healthy Norwegian volunteers: an optical coherence tomography study
<p>Abstract</p> <p>Background</p> <p>Ethnic, intersubject, interoperator and intermachine differences in measured macular thickness seem to exist. Our purpose was to collect normative macular thickness data in Norwegians and to evaluate the association between macular thickness and age, gender, parity, and contraception status.</p> <p>Methods</p> <p>Retinal thickness was measured by Stratus Optical Coherence Tomography in healthy subjects. Mean macular thickness (MMT) was analyzed by repeated measures ANOVA with three dependent regional MMT-variables for interaction with age, gender, parity and oral contraception use. Exploratory correlation with age by the Pearson correlation test, both before and after stratification by gender was performed. Differences in MMT between older and younger subjects, between oral contraception users and non-users, as well as parous and nulliparous women were studied by post-hoc Student's t-tests.</p> <p>Results</p> <p>Central MMT in Norwegians was similar to values earlier reported in whites. MMT in central areas of 1 and 2.25 mm in diameter were higher in males than in females. In younger subjects (≤43 years) differences in MMT between genders were larger than in the mixed age group, whereas in older subjects (>43 years) the small differences did not reach the set significance level. No differences were found in minimal foveolar thickness (MMFT) between the genders in any age group.</p> <p>Mean foveal thickness (1 mm in diameter) was positively associated with age in females (r = 0.28, p = 0.03). MMFT was positively associated with age in all groups and reached significance both in females and in mixed gender group (r = 0.20, p = 0.041 and r = 0.26, p = 0.044 respectively).</p> <p>Mean foveal thickness and MMFT were significantly higher in parous than in nulliparous women, and age-adjusted ANOVA for MMFT revealed a borderline effect of parity.</p> <p>Conclusions</p> <p>Age and gender should be taken into consideration when establishing normal ranges for MMT in younger subjects. The gender difference in retinal thickness in young, but not older adults suggests a gonadal hormonal influence. The possible association between parity and retinal structure and its clinical relevance, should be studied further.</p
Collisionally activated dissociation of protonated 2′-deoxycytidine, 2′-deoxyuridine, and their oxidatively damaged derivatives
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research
Molecular dynamics and density functional theory study on the corrosion inhibition of austenitic stainless steel in hydrochloric acid by two pyrimidine compounds
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