379 research outputs found
A spectrum result on maximal partial ovoids of the generalized quadrangle Q(4,q), q odd
In this article, we prove a spectrum result on maximal partial ovoids of the generalized quadrangle Q(4, q), q odd, i.e. for every integer k in the interval [a, b], where a approximate to q2 and b approximate to 9/10q2, there exists a maximal partial ovoid of Q(4, q), q odd, of size k. Since the generalized quadrangle IN(q) defined by a symplectic polarity of PG(3, q) is isomorphic to the dual of the generalized quadrangle Q(4, q), the same result is obtained for maximal partial spreads of 1N(q), q odd. This article concludes a series of articles on spectrum results on maximal partial ovoids of Q(4, q), on spectrum results on maximal partial spreads of VV(q), on spectrum results on maximal partial 1-systems of Q(+)(5,q), and on spectrum results on minimal blocking sets with respect to the planes of PG(3, q). We conclude this article with the tables summarizing the results
FDA and EMA Approvals of New Breast Cancer Drugs—A Comparative Regulatory Analysis
Breast cancer is the most common cancer in women worldwide and the solid tumor type for which the highest number of drugs have been approved to date. This study examines new drug approvals for breast cancer by the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMA), based on an analysis of regulatory documents from both agencies for the period from 1995 to 2018. Of the 29 breast cancer drugs approved over this time span, 17 received positive decisions from both the FDA and EMA, including all drugs licensed after 2008. Nineteen of the 25 FDA-approved drugs, but none of the EMA approvals, benefited from special regulatory pathways (such as fast track, breakthrough therapy, or priority review). In the U.S.A., four accelerated approvals were granted (of which one, for bevacizumab, was later revoked), while only two drugs received provisional approvals following EMA review. New breast cancer drugs were approved approximately twelve months earlier in the United States than in Europe. These results suggest that a broader use of special regulatory pathways by EMA could help to accelerate access to novel drugs for European breast cancer patients
Learning how to perform ultrasound-guided interventions with and without augmented reality visualization: a randomized study
OBJECTIVES
Augmented reality (AR), which entails overlay of in situ images onto the anatomy, may be a promising technique for assisting image-guided interventions. The purpose of this study was to investigate and compare the learning experience and performance of untrained operators in puncture of soft tissue lesions, when using AR ultrasound (AR US) compared with standard US (sUS).
METHODS
Forty-four medical students (28 women, 16 men) who had completed a basic US course, but had no experience with AR US, were asked to perform US-guided biopsies with both sUS and AR US, with a randomized selection of the initial modality. The experimental setup aimed to simulate biopsies of superficial soft tissue lesions, such as for example breast masses in clinical practice, by use of a turkey breast containing olives. Time to puncture(s) and success (yes/no) of the biopsies was documented. All participants completed questionnaires about their coordinative skills and their experience during the training.
RESULTS
Despite having no experience with the AR technique, time to puncture did not differ significantly between AR US and sUS (median [range]: 17.0 s [6-60] and 14.5 s [5-41], p = 0.16), nor were there any gender-related differences (p = 0.22 and p = 0.50). AR US was considered by 79.5% of the operators to be the more enjoyable means of learning and performing US-guided biopsies. Further, a more favorable learning curve was achieved using AR US.
CONCLUSIONS
Students considered AR US to be the preferable and more enjoyable modality for learning how to obtain soft tissue biopsies; however, they did not perform the biopsies faster than when using sUS.
KEY POINTS
• Performance of standard and augmented reality US-guided biopsies was comparable • A more favorable learning curve was achieved using augmented reality US. • Augmented reality US was the preferred technique and was considered more enjoyable
TENCompetence tools and I*Teach methodology in action: development of an active web-based teachers’ community
The article presents an example of how Information and Communication Technologies (ICT) can enhance the
process of teacher training, and how this can be used for lifelong competence development for teachers. The paper
describes the goals, settings, implementation and results of a pilot teachers’ training realized within the frame of the
European project TENCompetence. ICT tools developed in TENCompetence project were used to support the
introduction to the I*Teach didactical methodology developed in the frame of I*Teach Leonardo project. It became
clear that the ICT tools and didactical methodology offer a strong support for teachers’ professional development
Quantitative breast MRI: 2D histogram analysis of diffusion tensor parameters in normal tissue
Abstract : Object: Diffusion tensor imaging (DTI) of the breast may provide a powerful new approach for the detection of intraductal processes. The aim of this investigation was to characterize the relation between diffusion tensor parameters [fractional anisotropy (FA), mean diffusivity (MD)] in normal breast tissue to obtain information on the microenvironment of the diffusing water molecules and to provide a systematic approach for DTI analysis. Materials and methods: Seven female, healthy volunteers underwent prospective double-spin-echo prepared echo-planar diffusion-weighted sequence (TR/TE 8,250ms/74ms, b values 0 and 500s/mm (2), six encoding directions, 12 averages, 35 slices) in 4 consecutive weeks (3.0 T). Quantitative maps of diffusion tensor parameters were computed offline with custom routines. The interdependence of MD and FA in different voxels was analysed by linear and exponential regression. Results: All MD and FA maps were of excellent quality. A consistent pattern was observed in that lower fractional anisotropy values were more likely associated with higher mean diffusivity values. The dependence exhibited an exponential behavior with a correlation coefficient R=0.60 (R linear=0.57). Conclusion: The likelihood with which FA and MD values are observed in a voxel within normal breast tissue is characterized by a specific pattern, which can be described by an exponential model. Moreover, we could show that the proposed technique does not depend on the menstrual cycle
Autologous peripheral retinal pigment epithelium translocation in patients with subfoveal neovascular membranes
AIM: To evaluate the possibility of translocating autologous peripheral
retinal pigment epithelial (RPE) cells and enhance their adhesion to
improve functional outcome after choroidal neovascular membrane extracti
Supramolecular ionogels prepared with bis(amino alcohol)oxamides as gelators: ionic transport and mechanical properties
Supramolecular ionogels composed of an ionic liquid (IL) immobilized in a network of self- assembled low-molecular weight molecules have been attracting considerable interest due to their applicability as smart electrolytes for various electrochemical applications. Despite considerable scientific effort in this field, the design of a mechanically and thermally stable yet highly conductive supramolecular ionogels still remains a challenge. In this article, we report on a series of novel ionogels of three ILs containing different cations (imidazolium/pyrrolidinium) and anions (tetrafluoroborate/bis(trifluoromethylsulfonyl) imide) prepared using (S, S)-bis(amino alcohol)oxamides as gelators. The gelation behaviour of the oxamide compound depends strongly on the structural features of amino alcohol substituents. Among them, (S, S)- bis(valinol)oxamide (capable of gelling all three ILs) and (S, S)-bis(phenylalaninol)oxamide (capable of gelling ILs based on bis(trifluoromethylsulfonyl)imide with a concentration as low as ≈0.2 wt%) are highly efficient. All investigated supramolecular ionogels retain the high ionic conductivity and ion diffusion coefficients of their parent IL, even for high gelator concentrations. Further, at low temperatures we observe an enhancement of the ionic conductivity in ionogels of (i) 1- butyl-3-methylimidazolium tetrafluoroborate which can be attributed to specific interactions between ionic species and gelator molecules and (ii) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide due to inhibited crystallization. In contrast to ionic transport, mechanical strength of the ionogels shows a wider variation depending on the type and concentration of the oxamide gelator. Among all the ionogels, that of 1-butyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide prepared with 1 wt% (S, S)-bis(phenylalaninol)oxamide exhibits the best performance: optical transparency, stability over a wide temperature range, high conductivity and high mechanical strength. The results presented here reveal the versatile nature of bis(amino alcohol)oxamides as gelators and their high potential for preparing functionalized IL-based materials
The Combination of Ultraviolet-B and Vitamin K2 Exposure Effect on Fibroblast-like cell Number in Wistar Rats
Background: Vitamin D deficiency in children is one of the problems most often discussed and received attention from around the world today, especially during the Corona virus disease-19 (Covid-19) pandemic. Vitamin D3 increases the production of vitamin K2 protein and activates a protein involved in bone metabolism. Vitamin K2 increases bone formation by stimulating osteoblast differentiation, regulating mineralization of the extracellular matrix, regulating bone marker gene expression, and inhibiting osteoclastogenesis. Purpose: to analyzed the effect of sun exposure, Ultraviolet-B (UV-B) and vitamin K2 supplementation on fibroblast-like cell as bone formation marker in Wistar rats (Rattus novergicus). Methods: twenty-four samples divided into 4 groups namely control group, UV-B group, vitamin K2 group, combination of UV-B and vitamin K2 group. After 21 days, extraction of lower incisors was done to examine fibroblast-like cell number after treatment. After being decalcified, specimens underwent histological evaluation using Haemotoxylin and Eosin staining to observe the fibroblast-like cell number. Result: Data analysis of fibroblast like cells number expression using one way analysis of variance (ANOVA) test showed a significant difference between sample groups (p<0.05). Conclusion: The combination of UV-B exposure and vitamin K2 administration group increased of fibroblast-like cells in Wistar rats (R. novergicus)
Defining the genetic susceptibility to cervical neoplasia - a genome-wide association study
Funding: MAB was funded by a National Health and Medical Research Council (Australia) Senior Principal Research Fellowship. Support was also received from the Australian Cancer Research Foundation. JL holds a Tier 1 Canada Research Chair in Human Genome Epidemiology. The Seattle study was supported by the following grants: NIH, National Cancer Institute grants P01CA042792 and R01CA112512. Cervical Health Study (from which the NSW component was obtained) was funded by NHMRC Grant 387701, and CCNSW core grant. The Montreal study was funded by the Canadian Institutes of Health Research (grant MOP-42532) and sample processing was funded by the Reseau FRQS SIDA-MI. The Swedish Research Council, the Swedish Foundation for Strategic Research, the ALF/LUA research grant in Gothenburg and Umeå, the Lundberg Foundation, the Torsten and Ragnar Soderberg’s Foundation, the Novo Nordisk Foundation, and the European Commission grant HEALTH-F2-2008-201865-GEFOS, BBMRI.se, the Swedish Society of Medicine, the KempeFoundation (JCK-1021), the Medical Faculty of Umeå University, the County Council of Vasterbotten (Spjutspetsanslag VLL:159:33-2007). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptPeer reviewedPublisher PDFPublisher PD
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