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Acanthamoeba keratitis with bacterial, fungal superinfection or without it leads to development of an aggressive and long-standing corneal inflammation; up to now, the efficacy of its treatment stays doubtful and demands further investigation. For a long time, there were discussions on the possibility and expediency of corneal collagen cross-linking (PACK-CXL photo activated chromophore for keratitis) in patients with bacterial, fungal and Acanthamoeba keratitis. This article presents a clinical case of effective treatment of mixed etiology keratitis by multiple high fluence accelerated PACK-CXL in a patient with severe local toxico-allergic reaction.

Laser inscription of form-birefringent nanograting layers inside fused silica by ultrashort (femto-picosecond) laser pulses at 515 nm was studied as a function of laser, average power and pulsewidth in terms of fabrication regimes. Retardance magnitudes were acquired for single birefringent layers inscribed at different laser parameters, enabling fabrication of polarization-based spectral micro-filters in the form of few-layer microdevices and of microfluidic multi-color refractive-index chemo/biosensor.

Corneal collagen cross-linking became a permanent part of complex treatment for patients with different forms of corneal ectasia. In periodical literature, there are anecdotal reports concerning long-term results of this corneal disease therapy method, which is an isolated variant of photodynamic therapy. Purpose. To carry out a retrospective study of corneal collagen cross-linking long-term results in various ectatic corneal diseases. Materials and methods. Results of corneal collagen cross-linking in patients with ectatic forms of corneal dystrophy 6 years after surgery were analyzed. The nosological structure of the study included a group of patients with primary keratoconus, pellucid marginal corneal degeneration, secondary ectasias. The group with primary keratoconus includes 30 patients (31 eyes), that with pellucid marginal degeneration 10 patients (10 eyes), that with secondary ectasias 10 patients (10 eyes). Data of the diagnostic examination before surgery, intermediate data of the dynamic follow-up during 6 years of observation were used for the analysis. Corneal collagen cross-linking was performed in the first or second year of follow-up, followed by monitoring of changes in the state of the cornea after corneal collagen cross-linking for 4-5 years. Results. A statistically significant increase in visual acuity was observed after the corneal collagen cross-linking in patients with primary and secondary ectasias. In patients diagnosed with pellucid marginal degeneration, there was no statistically significant increase of visual function. A decrease in the corneal asymmetry index was revealed in all groups and confirmed by statistical analysis.

An efficient transformation of 2-aryl-1,1-dibromocyclopropanes under the action of sulfur trioxide activated nitrosyl chloride has been developed, providing a series of arylated 5-bromoisoxazoles with good yields. It is noteworthy that under the reported conditions the nitrosation–heterocyclization reaction proceeded with high regioselectivity leading exclusively to 3-aryl-5-bromoisoxazoles.

An efficient transformation of 2-aryl-1,1-dibromocyclopropanes under the action of sulfur trioxide activated nitrosyl chloride has been developed, providing a series of arylated 5-bromoisoxazoles with good yields. It is noteworthy that under the reported conditions the nitrosation–heterocyclization reaction proceeded with high regioselectivity leading exclusively to 3-aryl-5-bromoisoxazoles.

Reaction of the nine-nuclear cluster Ni9(HOOCCMe3)4(μ4-ΟΗ)3(μ3-OH)3 (OOCCMe3)12 (1) with pyridine results in the binuclear species Py4Ni2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (2). Thermolysis of 2 at 100−140 °C in toluene or xylene leads to complex Py2Ni2(HOOCCMe3)2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (3). This complex can be converted back in 2 by the reaction of 3 with 2 equiv of pyridine. Thermolysis of solid 3 in vacuo at 170 °C gives the binuclear tetra-bridged trimethylacetate Py2Ni2(μ-OOCCMe3)4 (4) which can be reverted in 3 by reaction with 1 equiv of H2O and 2 equiv of HOOCCMe3. Compound 4 might be also prepared by the reaction of the complexs L2Ni2(μ-OOCCMe3)4 (L = 2,3-lutidine (5), Et3N (6)) with pyridine at 40−80 °C in hexane or benzene solution. Complexes 5 and 6 are formed in an one-step reaction by interaction of complex 1 and ligand L. Complex Dipy2Ni2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (7), an isoelectronic analogue of complex 2, was prepared by reacting 1 with Dipy. Thermolysis of solid 7 at 170 °C in vacuo ...

Selective IR absorption at 1261 cm−1 enhanced by 455 times, was demonstrated for rhodamine 6G molecules, covering a 2D-photonic crystal, represented by a regular array of 4-micron wide holes in a 30 nm thick silver film on a CaF2 substrate. The reference absorption lines were taken near 2900 cm−1, where the IR radiation is freely channeling through the microholes, indicating the reference substrate coverage by the dye molecules for its relative internal calibration. The limit of background-free detection for the analyte was determined at the level ~10−2 monolayer.

The nonlinear Poisson-Boltzmann equation (PBE) governing biomolecular electrostatics neglects ion size and ion correlation effects, and recent research activity has focused on accounting for these effects to achieve better physical modeling realism. Here, attention is focused on the comparatively simpler challenge of addressing ion size effects within a continuum-based solvent modeling framework. Prior works by Borukhov et al. (Phys. Rev. Lett. 1997, 79, 435; Electrochim. Acta 2000, 46, 221) have examined the case of uniform ion size in considerable detail. Generalizations to accommodate different species ion sizes have been performed by Li (Nonlinearity 2009, 22, 811; SIAM J. Math. Anal. 2009, 40, 2536) and Zhou et al. (Phys. Rev. E 2011, 84, 021901) using a variational principle, Chu et al. (Biophys. J. 2007, 93, 3202) using a lattice gas model, and Tresset (Phys. Rev. E 2008, 78, 061506) using a generalized Poisson-Fermi distribution. The current work provides an alternative derivation using simple statistical mechanics principles that place the ion size effects and energy distributions on a consistent statistical footing. The resulting expressions differ from the prior nonuniform ion-size developments. However, all treatments reduce to the same form in the cases of uniform ion-size and zero ion size (the PBE). Because of their importance to molecular modeling and salt-dependent behavior, expressions for the salt sensitivities and ionic forces are also derived using the nonuniform ion size description. Emphasis in this article is on formulation and numerically robust evaluation; results are presented for a simple sphere and a previously considered DNA structure for comparison and validation. More extensive application to biomolecular systems is deferred to a subsequent article.

This paper outlines a novel method to suppress cavity vibration using flow-powered devices, denoted Flow Driven Oscillating Vortex Generators (FDOVGs). This technology, recently successfully applied to control boundary layer behavior over 3D wings, offers the prospect of substantial mitigation of cavity resonance vibrations with mechanical requirements limited to steady state deployment and retraction of these devices. Low Mach number tests, detailed in this paper, have shown considerable promise, with dramatic reductions (15-30 dB) in tonal noise with no power input when applied to a representative cavity in a wind tunnel test.

Active flow control can be effective in tailoring boundary layer dynamics, but concepts developed to date have typically imposed significant design penalties because of the power and hardware required. This paper discusses the development and demonstration of a family of self-excited Flow Driven Oscillating Vortex Generators (FDOVGs) which oscillate at frequencies where the induced vortical flows have length scales that are of the order of the scale of the aerodynamic surface. FDOVGs receive power from the mean flow to operate and generate large amplitude oscillations that are useful for controlling boundary layer dynamics. This project entailed sequential concept development, analysis, design, fabrication, and testing of candidate FDOVG devices. Experimental activity included both studies of stand-alone FDOVGs as well as integrated tests of FDOVG arrays on lifting wings. Results clearly demonstrated the ability of these arrays to effect considerable improvements to attached flow with zero input power. In addition, several candidate mechanisms for deploying FDOVGs were developed, potentially enabling these improvements while also permitting device retraction, and, hence, yielding negligible cruise drag penalty. The demonstrations in hand are the first step in the development of micro- as well as macro-scale FDOVG devices with applications on micro air vehicles, UAVs, subsonic transports, and road vehicles.

Use of Shape Memory Alloy (SMA) actuation technology is a candidate method for reducing weight and power requirements for inlet flow control actuators in prospective supersonic passenger aircraft. The high speed/high Mach operating points of such aircraft can also call for the use of High Temperature SMAs, with transition temperatures beyond those of typical binary NiTi alloys. This paper outlines a demonstration project that entailed both testing and assessment of newly developed NiTiPt HTSMAs, as well as their use in an actuation application representative of inlet configurations. The project featured benchtop testing of an HTSMA-actuated ramp model as well as experiments in a high speed wind tunnel at loads representative of supersonic conditions. The ability of the model to generate adequate force and actuation stroke for this application is encouraging evidence the feasibility of NiTiPt-based devices for inlet flow control.

A second-power yield of resonantly enhanced third harmonic and three-photon luminescence of 744 nm femtosecond laser pump pulses, weakly focused onto a layer of silver nanorolls on a silica substrate, was spectrally detected in the fluence range of 4–20 mJ cm−2, saturating at higher fluences. The third-harmonic yield and its saturation were explored in terms of ultrafast carrier dynamics, based on direct three-photon or cascade one- and two-photon transitions balanced by Auger recombination (and the final band-filling effect) which limited the radiative recombination output in the form of the third harmonic and three-photon luminescence.