1,792 research outputs found
Backward whirl in a simple rotor supported on hydrodynamic bearings
The asymmetric nature of the fluid film stiffness and damping properties in rotors supported on fluid film bearings causes a forward or a backward whirl depending on the bearing parameters and the speed of the rotor. A rotor was designed to exhibit backward synchronous whirl. The rotor-bearing system exhibited split criticals, and a backward whirl was observed between the split criticals. The orbital diagrams show the whirl pattern
Diagnostic value of risk malignancy index (RMI) for detection of malignancies in clinically diagnosed ovarian masses and to evaluate the validity of individual constituent parameter of risk malignancy index
Background: Pre-operative knowledge regarding the nature of ovarian mass is necessary in order to plan surgery. Risk malignancy index (RMI) is a simple scoring system based on three factors serum CA 125, USG score and menopausal status. The RMI was interpreted as 1) score >250=high risk, 2) 25-250=intermediate risk, 3) score cut-off values and 27.27% (n=21) had RMI >250. In cases where RMI>250, 18 out of 21 were malignant. In cases where USG score was 4, 19 out of 34 were malignant. Of the cases where serum CA125 level was > cut-off values 16 out of 21 were found to be malignant. RMI showed better sensitivity of 85.71%, specificity of 94.64%, PPV of 85.71%, NPV of 94.64% and diagnostic accuracy of 92.20%.Conclusions: RMI is highly valuable and reliable in differentiating benign and malignant ovarian lesions and facilitates selection of cases for conservative management and oncology referral
Copper-containing mesoporous bioactive glass promotes angiogenesis in an in vivo zebrafish model
The osteogenic and angiogenic responses of organisms to the ionic products of degradation of bioactive glasses (BGs) are being intensively investigated. The promotion of angiogenesis by copper (Cu) has been known for more than three decades. This element can be incorporated to delivery carriers, such as BGs, and the materials used in biological assays. In this work, Cu-containing mesoporous bioactive glass (MBG) in the SiO2-CaO-P2O5 compositional system was prepared incorporating 5% mol Cu (MBG-5Cu) by replacement of the corresponding amount of Ca. The biological effects of the ionic products of MBG
biodegradation were evaluated on a well-known endothelial cell line, the bovine aorta endothelial cells (BAEC), as well as in an in vivo zebrafish (Danio rerio) embryo assay. The results suggest that ionic products of both MBG (Cu free) and MBG-5Cu materials promote angiogenesis. In vitro cell cultures show that the ionic dissolution products of these materials are not toxic and promote BAEC viability and migration.
In addition, the in vivo assay indicates that both exposition and microinjection of zebrafish embryos with Cu free MBG material increase vessel number and thickness of the subintestinal venous plexus (SIVP), whereas assays using MBG-5Cu enhance this effect.The authors gratefully acknowledge the financial support provided by the Andalusian Ministry of Economy, Science and Innovation
(Proyectos Excelencia Grants no. P10-CTS-6681 and no. P12-CTS-1507) and Spanish Ministry of Economy and Competitivity
(BIO2014-56092-R). LBRS acknowledges the CONACYT-Mexico Fellowship PhD Program
Knowledge and awareness of cervical cancer, its prevention and attitude towards human papillomavirus vaccine among medical students
Background: Cervical cancer is still one of the most common cancers affecting females in India, leading to a lot of mortality and morbidity. The objective of this study was to assess the awareness of the human papillomavirus (HPV) infections and vaccination among the medical students of a tertiary care teaching hospital.Methods: A total 300 final year I and II medical students were requested to complete a questionnaire regarding cervical cancer, primary and secondary preventive measures and attitude of students towards HPV vaccination and the answers were then analysed.Results: Among 300 medical students, 46.6% were males and 53.4% were females. Most of them were aware of the common risk factors like early marriage (92.7%), multiple partners (99%), multiparity (83.3%) and HPV exposure (85.7%). Most were aware of the cervical cancer symptoms like offensive vaginal discharge (70%), irregular vaginal bleeding (92.7%) and postcoital bleeding (80.3%). 90% were aware that cervical cancer is preventable and 74% were aware that vaccine is available in India. 70% were aware about the best age to vaccinate is 9-13 years. About 10% were already vaccinated and all were females. Out of 270 students who have not administered HPV vaccine, 53.4% didn’t take the vaccine because of lack of awareness. High cost (18.8%), fear of side effects (13.8%) and doubt on efficacy (14%) were the other reasons reported for non-administration of vaccines.Conclusions: The study showed that there were gaps in knowledge regarding HPV infection and vaccination existed amongst the medical students. So, awareness among the students should be created and a more integrated teaching regarding various aspects of HPV infection, cervical cancers and its prevention needs to be introduced in the medical education system
‘Diagrams of Motion’:Stop-Motion Animation as a Form of Kinetic Sculpture in the Short Films of Jan Švankmajer and the Brothers Quay
Jean-Luc Godard wrote that ‘The cinema is not an art which films life; the cinema is something between art and life’ (cited in Roud’s, 2010, biography of Godard), an observation particularly true of stop-motion animation. The filmmakers discussed in this essay, Jan Švankmajer and the Brothers Quay, share a fascination with the latent content of found objects; they believe that forgotten toys, discarded tools and other such objects contain echoes of past experiences. Extrapolating Švankmajer’s belief that memories are imparted to the objects we touch, the manipulation of his found objects as puppets in his films becomes a means of evoking and repurposing their latent content, just as the Quays develop their dreamlike films from the psychic content they perceive in their armatures. Making a case study of a selection of these animators’ short films, this article examines the practice of stop-motion animation against that of kinetic sculpture, unpicking the complexities of the relationship between the inherently static mediums of sculpture and photography – symbolic of a fixed moment in time – and that of stop-motion animation, a temporal pocket in which these fossilized moments are revived once more
Downregulation of CREB expression in Alzheimer's brain and in Aβ-treated rat hippocampal neurons
<p>Abstract</p> <p>Background</p> <p>Oxidative stress plays an important role in neuronal dysfunction and neuron loss in Alzheimer's brain. Previous studies have reported downregulation of CREB-mediated transcription by oxidative stress and Aβ. The promoter for CREB itself contains cyclic AMP response elements. Therefore, we examined the expression of CREB in the hippocampal neurons of Tg2576 mice, AD post-mortem brain and in cultured rat hippocampal neurons exposed to Aβ aggregates.</p> <p>Results</p> <p>Laser Capture Microdissection of hippocampal neurons from Tg2576 mouse brain revealed decreases in the mRNA levels of CREB and its target, BDNF. Immunohistochemical analysis of Tg2576 mouse brain showed decreases in CREB levels in hippocampus and cortex. Markers of oxidative stress were detected in transgenic mouse brain and decreased CREB staining was observed in regions showing abundance of astrocytes. There was also an inverse correlation between SDS-extracted Aβ and CREB protein levels in Alzheimer's post-mortem hippocampal samples. The levels of CREB-regulated BDNF and BIRC3, a caspase inhibitor, decreased and the active cleaved form of caspase-9, a marker for the intrinsic pathway of apoptosis, was elevated in these samples. Exposure of rat primary hippocampal neurons to Aβ fibrils decreased CREB promoter activity. Decrease in CREB mRNA levels in Aβ-treated neurons was reversed by the antioxidant, N-acetyl cysteine. Overexpression of CREB by adenoviral transduction led to significant protection against Aβ-induced neuronal apoptosis.</p> <p>Conclusions</p> <p>Our findings suggest that chronic downregulation of CREB-mediated transcription results in decrease of CREB content in the hippocampal neurons of AD brain which may contribute to exacerbation of disease progression.</p
Measurements of the branching fractions of B+→ppK+ decays
The branching fractions of the decay B+ → pp̄K+ for different intermediate states are measured using data, corresponding to an integrated luminosity of 1.0 fb-1, collected by the LHCb experiment. The total branching fraction, its charmless component Mpp̄ < 2.85 GeV/c2 and the branching fractions via the resonant cc̄ states η c(1S) and ψ(2S) relative to the decay via a J/ψ intermediate state are [Equation not available: see fulltext.] Upper limits on the B + branching fractions into the η c(2S) meson and into the charmonium-like states X(3872) and X(3915) are also obtained
Study of B0(s)→K0Sh+h′− decays with first observation of B0s→K0SK±π∓ and B0s→K0Sπ+π−
A search for charmless three-body decays of B 0 and B0s mesons with a K0S meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B0(s)→K0Sh+h′− decay modes (h (′) = π, K), relative to the well measured B0→K0Sπ+π− decay, are obtained. First observation of the decay modes B0s→K0SK±π∓ and B0s→K0Sπ+π− and confirmation of the decay B0→K0SK±π∓ are reported. The following relative branching fraction measurements or limits are obtained B(B0→K0SK±π∓)B(B0→K0Sπ+π−)=0.128±0.017(stat.)±0.009(syst.), B(B0→K0SK+K−)B(B0→K0Sπ+π−)=0.385±0.031(stat.)±0.023(syst.), B(B0s→K0Sπ+π−)B(B0→K0Sπ+π−)=0.29±0.06(stat.)±0.03(syst.)±0.02(fs/fd), B(B0s→K0SK±π∓)B(B0→K0Sπ+π−)=1.48±0.12(stat.)±0.08(syst.)±0.12(fs/fd)B(B0s→K0SK+K−)B(B0→K0Sπ+π−)∈[0.004;0.068]at90%CL
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