308 research outputs found
Peak effect in laser ablated DyBa2Cu3O7-d films at microwave frequencies at subcritical currents
In this paper we report the observation of a peak in the microwave surface
resistance (at frequencies ~10GHz) of laser ablated DyBa2Cu3O7-d films in
magnetic field ranging from 2 to 9kOe (||c) close to the superconducting
transition temperature (Tc(H)). The exact nature of peak is sample dependent
but it follows a general behaviour. The peak shifts to lower temperature when
the magnetic field is increased. It has strong frequency dependence and the
peak is pronounced at frequencies close to the depinning frequency of the flux
line lattice. From the observed temperature and field dependence we argue that
this peak is associated with the order disorder transition of the flux line
lattice close to Tc(H).Comment: 8 pages, 2 pages (accepted for publication in JAP, Intermag symposium
proceeding
Coupled Phonons, Magnetic Excitations and Ferroelectricity in AlFeO3: Raman and First-principles Studies
We determine the nature of coupled phonons and magnetic excitations in AlFeO3
using inelastic light scattering from 5 K to 315 K covering a spectral range
from 100-2200 cm-1 and complementary first-principles density functional
theory-based calculations. A strong spin-phonon coupling and magnetic ordering
induced phonon renormalization are evident in (a) anomalous temperature
dependence of many modes with frequencies below 850 cm-1, particularly near the
magnetic transition temperature Tc ~ 250 K, (b) distinct changes in band
positions of high frequency Raman bands between 1100-1800 cm-1, in particular a
broad mode near 1250 cm-1 appears only below Tc attributed to the two-magnon
Raman scattering. We also observe weak anomalies in the mode frequencies at ~
100 K, due to a magnetically driven ferroelectric phase transition.
Understanding of these experimental observations has been possible on the basis
of first-principles calculations of phonons spectrum and their coupling with
spins
An Examplar Based Video Inpainting using Dictionary Based Method
Inpainting is a skill of rebuilding lost or selected part from the image based on relatedor available information. Reconstruction of missing parts in videos is used extensively nowadays. A method for video inpainting usingexamplar-based inpainting is introduced in the system. The examplar based inpainting samples and copies best matching texture patches using texture synthesis. Matching patches are extracted from the known part of the frames from the video. Input frames are extracted and inpainted using examplar based method. For that dictionary is maintained which consists of legal patches. The input picture isinpainted several times with different parameters. Then it is combined and details are recovered to get the final inpainted video
Mechanisms and treatment of ischaemic stroke: insights from genetic associations
The precise pathophysiology of ischaemic stroke is unclear, and a greater understanding of the different mechanisms that underlie large-artery, cardioembolic and lacunar ischaemic stroke subtypes would enable the development of more-effective, subtype-specific therapies. Genome-wide association studies (GWASs) are identifying novel genetic variants that associate with the risk of stroke. These associations provide insight into the pathophysiological mechanisms, and present opportunities for novel therapeutic approaches. In this Review, we summarize the genetic variants that have been linked to ischaemic stroke in GWASs to date and discuss the implications of these associations for both our understanding and treatment of ischaemic stroke. The majority of genetic variants identified are associated with specific subtypes of ischaemic stroke, implying that these subtypes have distinct genetic architectures and pathophysiological mechanisms. The findings from the GWASs highlight the need to consider whether therapies should be subtype-specific. Further GWASs that include large cohorts are likely to provide further insights, and emerging technologies will complement and build on the GWAS findings
Institutional distance and foreign subsidiary performance in emerging markets: moderating effects of ownership strategy and host-country experience
Institutional distance has been known to be an important driver of Multinational Enterprises’ strategies and performance in host countries. Based on a large panel dataset of 10562 firms operating in 17 emerging markets and spanning 80 home countries, we re-examine the relationship described by Gaur and Lu (2007) between regulatory institutional distance and subsidiary performance. We extend this research by (1) examining this relationship in the context of emerging markets, (2) examining the moderating effects of ownership strategy and host-country experience within the context of emerging markets and (3) accounting for a greater variety of institutions by including a large number of home and host countries. We find that institutional distance negatively affects subsidiary performance in emerging markets. Our findings also show that the negative effects of institutional distance on subsidiary performance are lesser for subsidiaries with partial ownership (than for subsidiaries with full ownership) and for subsidiaries with greater host-country experience. We discuss our findings with respect to Gaur and Lu’s model, which explores the relationships between these variables in a general context
Growth of CaF2 buffer on Si using low energy cluster beam deposition technique and study of its properties
International audienc
The Ku-binding motif is a conserved module for recruitment and stimulation of non-homologous end-joining proteins
The Ku-binding motif (KBM) is a short peptide module first identified in APLF that we now show is also present in Werner syndrome protein (WRN) and in Modulator of retrovirus infection homologue (MRI). We also identify a related but functionally distinct motif in XLF, WRN, MRI and PAXX, which we denote the XLF-like motif. We show that WRN possesses two KBMs; one at the N terminus next to the exonuclease domain and one at the C terminus next to an XLF-like motif. We reveal that the WRN C-terminal KBM and XLF-like motif function cooperatively to bind Ku complexes and that the N-terminal KBM mediates Ku-dependent stimulation of WRN exonuclease activity. We also show that WRN accelerates DSB repair by a mechanism requiring both KBMs, demonstrating the importance of WRN interaction with Ku. These data define a conserved family of KBMs that function as molecular tethers to recruit and/or stimulate enzymes during NHEJ
Multiferroic and magnetoelectric nature of GaFeO3, AlFeO3 and related oxides
GaFeO3, AlFeO3 and related oxides are ferrimagnetic exhibiting
magnetodielectric effect. There has been no evidence to date for
ferroelectricity and hence multiferroicity in these oxides. We have
investigated these oxides as well as oxides of the composition
Al1-x-yGaxFe1+yO3 (x = 0.2, y = 0.2) for possible ferroelectricity by carrying
out pyroelectric measurements. These measurements establish the occurrence of
ferroelectricity at low temperatures below the N\`eel temperature in these
oxides. They also exhibit significant magnetoelectric effect. We have tried to
understand the origin of ferroelectricity based on non-centrosymmetric magnetic
ordering and disorder by carrying out first-principles calculations.Comment: 21 pages,7 figure
Growth of CaF2 buffer on Si using low energy cluster beam deposition technique and study of its properties
The comparison of clinical outcomes of endophthalmitis from fluoroquinolone-resistant and susceptible bacteria
To identify patients who developed acute-onset endophthalmitis after clear corneal cataract surgery, and to compare treatment outcomes between cases caused by fluoroquinolone susceptible organisms versus fluoroquinolone resistant organisms.
Retrospective case series.
Patients who developed endophthalmitis within six weeks of cataract surgery, and were treated between January 1996 and December 2008 at Bascom Palmer Eye Institute in Miami, Florida, were identified retrospectively. Clinical features, organisms cultured, and visual acuity outcomes were evaluated.
A total of 97 patients met study criteria, and 37 (38%) demonstrated in vitro fluoroquinolone resistance. All fluoroquinolone resistant endophthalmitis in the study was caused by either Staphylococcus epidermidis (n = 32) or Staphylococcus aureus (n = 5). Presenting clinical features were similar between fluoroquinolone resistant and fluoroquinolone susceptible groups. Final visual acuity was >/=20/40 in 49% of fluoroquinolone-resistant cases and 42% of fluoroquinolone-susceptible cases. All fluoroquinolone-resistant isolates were susceptible to vancomycin.
In the current study, approximately one-third of isolates were resistant to fluoroquinolones. There was no significant difference in clinical outcomes in this study, regardless of fluoroquinolone susceptibility
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