188 research outputs found
Intrinsic defects in silicon carbide LED as a perspective room temperature single photon source in near infrared
Generation of single photons has been demonstrated in several systems.
However, none of them satisfies all the conditions, e.g. room temperature
functionality, telecom wavelength operation, high efficiency, as required for
practical applications. Here, we report the fabrication of light emitting
diodes (LEDs) based on intrinsic defects in silicon carbide (SiC). To fabricate
our devices we used a standard semiconductor manufacturing technology in
combination with high-energy electron irradiation. The room temperature
electroluminescence (EL) of our LEDs reveals two strong emission bands in
visible and near infrared (NIR), associated with two different intrinsic
defects. As these defects can potentially be generated at a low or even single
defect level, our approach can be used to realize electrically driven single
photon source for quantum telecommunication and information processing
Nanotransfer Printing of Organic and Carbon Nanotube Thin-Film Transistors on Plastic Substrates
A printing process for high-resolution transfer of all components for organic
electronic devices on plastic substrates has been developed and demonstrated
for pentacene (Pn), poly (3-hexylthiophene) and carbon nanotube (CNT) thin-film
transistors (TFTs). The nanotransfer printing process allows fabrication of an
entire device without exposing any component to incompatible processes and with
reduced need for special chemical preparation of transfer or device substrates.
Devices on plastic substrates include a Pn TFT with a saturation, field-effect
mobility of 0.09 cm^2 (Vs)^-1 and on/off ratio approximately 10^4 and a CNT TFT
which exhibits ambipolar behavior and no hysteresis.Comment: to appear in Applied Physics Letter
The use of medicaments in the management of symptomatic irreversible pulpitis: a community-based cohort study
Aim: To investigate patient outcomes from either pulpotomy or pulpectomy for the management of symptomatic irreversible pulpitis, with and without application of antibiotic/corticosteroid pastes in urgent primary dental care settings in the United Kingdom. Methodology: All patients receiving intervention for symptomatic irreversible pulpitis in three different primary care settings were invited to participate. Pre-operatively, data regarding patients’ numerical ratings scale (NRS), pain score (0-10), analgesic use, oral-health impact profile-14 (OHIP-14) and need for time away from work were collected. For seven days post operatively, participants recorded their NRS pain score, global rating of change score, medication use and their ability to work. Analysis used a mixed-effects model with post-hoc Tukey’s multiple comparisons test for continuous data and chi-squared or Fisher\ub4s exact test for categorical data. To test the effect of the corticosteroid/antibiotic paste, pulpectomy and pulpotomy groups were combined following Mantel-Haenszel stratified analysis or a weighted average of the difference between pulpotomy and pulpectomy with and without the use of corticosteroid/antibiotic paste. A binary composite score was constructed using pre- and post-operative data, whereby overall treatment success was defined as: i. patients did not return for treatment due to pain by day seven; ii. at day three there was a 33% (or 2-points) reduction in NRS pain score; iii. there was a change score of +3 in global rating; iv. the patient was no-longer using analgesia and able to return to work. Results Eighty-five participants were recruited, with 83 completing follow-up. Overall treatment success was 57%, with 25% of participants returning for more treatment due to inadequate pain relief. Overall treatment success did not differ between the two groups (p=0.645), although patients self-reported greater improvement with an antibiotic/corticosteroid dressing for global rating of change (p=0.015). Conclusions: This study identified limited evidence of improved outcomes using antibiotic/corticosteroid dressings in the management of symptomatic irreversible pulpitis in the emergency setting. Further clinical research is needed to understand if these medications are beneficial in affording pain relief, above that of simple excision of irreversibly inflamed pulp tissue. Funding This study was funded by the European Society of Endodontology Young Investigator Grant (2020). Conflict of interest None to declare
Follicular regulatory T cells control humoral autoimmunity via NFAT2-regulated CXCR5 expression
Maturation of high-affinity B lymphocytes is precisely controlled during the germinal center reaction. This is dependent on CD4(+)CXCR5(+) follicular helper T cells (TFH) and inhibited by CD4(+)CXCR5(+)Foxp3(+) follicular regulatory T cells (TFR). Because NFAT2 was found to be highly expressed and activated in follicular T cells, we addressed its function herein. Unexpectedly, ablation of NFAT2 in T cells caused an augmented GC reaction upon immunization. Consistently, however, TFR cells were clearly reduced in the follicular T cell population due to impaired homing to B cell follicles. This was TFR-intrinsic because only in these cells NFAT2 was essential to up-regulate CXCR5. The physiological relevance for humoral (auto-)immunity was corroborated by exacerbated lupuslike disease in the presence of NFAT2-deficient TFR cells
European regulatory agenices should employ full time statisticians
No abstract available
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