Introducing the black hole

The quasi-stellar object, the pulsar, the neutron star have all come onto the scene of physics within the space of a few years. Is the next entrant destined to be the black hole? If so, it is difficult to think of any development that could be of greater significance. A black hole, whether of “ordinary size” (approximately one solar mass, 1 M⊙) or much larger (around 10^6 M⊙ to 10^10 M⊙, as proposed in the nuclei of some galaxies), provides our “laboratory model” for the gravitational collapse, predicted by Einstein's theory, of the universe itself

‘en pathos’

`en pathos ` A Greek term that translates to ` in passion ` . The human figure is a timeless and classic subject that has always bestirred feelings of passion in the hearts of both artist and viewer. It can easily take a lifetime\u27s artistic endeavors to master just a tiny aspect of the figure\u27s potential. More important than the literal realm of the figure, there also lies a subjective realm, a place where my work is created and lives.....a place `between\u27. In trying to capture the essence of the human figure, each artistic medium offers its own unique visual interpretation, be it with paint, ink, charcoal, clay, metal or wood. My philosophy as a visual artist is to welcome risk and chance, and to nourish interest into passion.....for the true artist\u27s work is most certainly created.....\u27en pathos\u27

Enabling III-V-based optoelectronics with low-cost dynamic hydride vapor phase epitaxy

Silicon is the dominant semiconductor in many semiconductor device applications for a variety of reasons, including both performance and cost. III-V materials have improved performance compared to silicon, but currently they are relegated to applications in high-value or niche markets due to the absence of a low-cost, high-quality production technique. Here we present an advance in III-V materials synthesis using hydride vapor phase epitaxy that has the potential to lower III-V semiconductor deposition costs by orders of magnitude while maintaining the requisite optoelectronic material quality that enables III-V-based technologies to outperform Si. We demonstrate the impacts of this advance by addressing the use of III-Vs in terrestrial photovoltaics, a highly cost-constrained market. The emergence of a low-cost III-V deposition technique will enable III-V electronic and opto-electronic devices, with all the benefits that they bring, to permeate throughout modern society.Comment: pre-prin

Spherical light, arbitrary nonparaxial accelerating beams and femtosecond laser micromachining of curved profiles

International audienceWe review our recent results applying caustics wave theory to the generation of arbitrary curved accelerating beams and their use in the field of femtosecond laser materials processing. We report experimental realization of highly nonparaxial accelerating beams with circular, parabolic and quartic trajectories that extend over more than 95 degrees of arc as well as spherical optical fields. We also report femtosecond laser curved edge profiling

Persistence of treatment in patients with ulcerative colitis who responded to tofacitinib therapy: data from the open-label, long-term extension study, OCTAVE open

Tofacitinib is an oral Janus kinase inhibitor for the treatment of ulcerative colitis (UC). Aim:This post hoc analysis evaluated tofacitinib persistence in patients with UC in OCTAVE Open, an open-label, long-term extension study of patients receiving tofacitinib 5 or 10 mg twice daily. Methods: Kaplan-Meier estimates for tofacitinib drug survival and reasons for discontinuations were evaluated. Baseline factors were analysed as predictors of persistence. Results:This analysis included 603 patients: 280 entered OCTAVE Open with a clinical response (164 in remission and 116 not in remission), 220 were delayed responders, 75 were retreatment responders and 35 were dose escalation responders, treated for up to 7 years in OCTAVE Open. Of these, 118 (42.1%) responders, 121 (55.0%) delayed responders, 40 (53.3%) retreatment responders and 17 (48.6%) dose escalation responders discontinued tofacitinib with a median time to discontinuation of 5.6, 4.5, 4.0 and 4.4 years, respectively. The estimated 2- and 5-year drug survival rates in the responders (including patients in remission and not in remission) were 73.9% and 54.5%, respectively. Corresponding persistence values for delayed responders were 69.5% and 45.2%, for retreatment responders, 70.7% and 40.0%, and for dose escalation responders, 74.3% and 32.8%. ConclusionIn: OCTAVE Open, a high proportion of patients maintained tofacitinib treatment, with the median survival by group ranging from 4.0 to 5.6 years although these analyses are post hoc and limited by sample size. Further research should focus on factors to enhance persistence with tofacitinib treatment in patients with UCThis study was sponsored by Pfizer. Medical writing support, under the guidance of the authors, was provided by Helen Findlow, PhD, CMC Connect, McCann Health Medical Communications and was funded by Pfizer Inc, New York, NY, USA in accordance with Good Publication Practice (GPP3) guidelines (Ann Intern Med. 2015;163:461–464

Filamentation of high-angle nondiffracting beams and applications to ultrafast laser processing

International audienceWe report on filamentation of nondiffracting beams and show that the intense light-matter interaction regime achieved on long distances allows for an enhanced control on ultrashort laser deep ablation

High precision differential abundance measurements in globular clusters: Chemical inhomogeneities in NGC 6752

We report on a strictly differential line-by-line analysis of high-quality UVES spectra of bright giants in the metal-poor globular cluster NGC 6752. We achieved high precision differential chemical abundance measurements for Fe, Na, Si, Ca, Ti, Cr, Ni,