1,2-Dimethyl-4,5-diphenylbenzene determined on a Bruker SMART X2S benchtop crystallographic system

The title compound, C(20)H(18), has two crystallographically independent molecules in the asymmetric unit. The phenyl substituents of molecule A are twisted away from the plane defined by the central benzene ring by 131.8 (2) and -52.7 (3)degrees. The phenyl substituents of molecule B are twisted by -133.3 (2) and 50.9 (3)degrees. Each molecule is stabilized by a pair of intraMolecular C(aryl, sp(2))-H center dot center dot center dot pi interactions, as well as by several interMolecular C(methyl, sp(3))-H center dot center dot center dot pi interactions

2,3-Bis(bromomethyl)-1,4-diphenylbenzene

In the title compound, C(20)H(16)Br(2), the terminal phenyl groups are twisted away from the central ring by approximately 55 and -125 degrees (average of four dihedral angles each), respectively. The crystal structure is stabilized by a combination of interMolecular and intraMolecular interactions including interMolecular pi-pi stacking interactions [C atoms of closest contact = 3.423 ( 5) angstrom]

Repentir: Digital exploration beneath the surface of an oil painting

Repentir is a mobile application that employs marker-less tracking and augmented reality to enable gallery visitors to explore the under drawing and successive stages of pigment beneath an oil painting's surface. Repentir recognises the position and orientation of a specific painting within a photograph and precisely overlays images that were captured during that painting's creation. The viewer may then browse through the work's multiple states and closely examine its painted surface in one of two ways: sliding or rubbing. Our current prototype recognises realist painter Nathan Walsh's most recent work, "Transamerica". Repentir enables the viewer to explore intermediary stages in the painting's development and see what is usually lost within the materially additive painting process. The prototype offers an innovative approach to digital reproduction and provides users with unique insights into the painter's working method

Efficient Coupling between Dielectric-Loaded Plasmonic and Silicon Photonic Waveguides

The realization of practical on-chip plasmonic devices will require efficient coupling of light into and out of surface plasmon waveguides over short length scales. In this letter, we report on low insertion loss for polymer-on-gold dielectric-loaded plasmonic waveguides end-coupled to silicon-on-insulator waveguides with a coupling efficiency of 79 ± 2% per transition at telecommunication wavelengths. Propagation loss is determined independently of insertion loss by measuring the transmission through plasmonic waveguides of varying length, and we find a characteristic surface-plasmon propagation length of 51 ± 4 μm at a free-space wavelength of λ = 1550 nm. We also demonstrate efficient coupling to whispering-gallery modes in plasmonic ring resonators with an average bending-loss-limited quality factor of 180 ± 8

The effects of hydration dehydration on rigid gas permeable contact lenses

The base curves of eighteen rigid gas permeable lenses of various powers and manufactors mere measured after hydration-dehydration cycles. The Halsey Lenscope allowed measuring of the central as well as peripheral base curves. The general trend of the measurements, verified the hypothesized flattening of the central and steepening of the peripheral base curve with medium and high minus tenses. This observation might explain the clinical mystery of a measured flattened base curve accompanied by symptoms of a tight lens

How close is the nearest node in a wireless network?

The ability of small-cell wireless networks to self-organize is crucial for improving capacity and performance in modern communication networks. This paper considers one of the most basic questions: what is the expected distance to a cell's nearest neighbour in a spatially distributed network? We analyse a model problem in the asymptotic limit of large total received signal and compare the accuracy of different heuristics. We also analytically consider the effects of fading. Our analysis shows that the most naive heuristic systematically underestimates the distance to the nearest node; this is substantially corrected in cases of interest by inclusion of the next-order asymptotic term. We illustrate our theoretical results explicitly or several combinations of signal and path loss parameters and show that our theory is well supported by numerical simulations. </p

2,5-Dichloro­thio­phene 1,1-dioxide

The complete mol­ecule of the title compound, C4H2Cl2O2S, is generated by crystallographic twofold symmetry, with the S atom lying on the rotation axis. In the crystal, the molecules are linked by C—H⋯O hydrogen bonds.

Dual High Flow Oxygen Therapy and CPAP Ventilation in a Single Device for COVID-19

High flow oxygen therapy (HFOT) and Continuous positive airway pressure (CPAP) could be considered the most important ventilatory therapies during the COVID-19 pandemic because of their frequency of use. There are many devices on the market which provide this type of ventilatory support, and these should be distinguished from one another by their efficacy, versatility, patient comfort, hygiene and cost. We evaluated the AquaVENT FD140i from Armstrong Medical, which delivers both HFOT and CPAP, concluding that it provides two potentially efficacious treatments to COVID-19 patients, while its long-life battery facilitates transfers for escalation and de-escalation of care. We compared the AquaVENT FD140i with the Fisher &amp; Paykel MR850, which is a gold standard in the market. We also looked at the compatibility of their humidifier and disposables with Armstrong Medical devices. The results of this study suggest the compatibility of both systems, which has the potential to reduce consumable costs