Purpose To determine the rate of progression of eyes with subclinical diabetic macular edema (DME) to clinically apparent DME or DME necessitating treatment during a 2-year period. Methods In all, 43 eyes from 39 study participants with subclinical DME, defined as absence of foveal center edema as determined with slit lamp biomicroscopy but a center point thickness (CPT) between 225 and 299 lm on time domain (Stratus, Carl Zeiss Meditec) optical coherence tomography (OCT) scan, were enrolled from 891 eyes of 582 subjects screened. Eyes were evaluated annually for up to 2 years for the primary outcome, which was an increase in OCT CPT of at least 50 lm from baseline and a CPT of at least 300 lm, or treatment for DME (performed at the discretion of the investigator). Results The cumulative probability of meeting an increase in OCT CPT of at least 50 lm from baseline and a CPT of at least 300 lm, or treatment for DME was 27% (95% confidence interval (CI): 14%, 38%) by 1 year and 38% (95% CI: 23%, 50%) by 2 years. Conclusions Although subclinical DME may be uncommon, this study suggests that between approximately one-quarter and one-half of eyes with subclinical DME will progress to more definite thickening or be judged to need treatment for DME within 2 years after its identification.

These data suggest that decreases in plasma free-VEGF levels are greater after treatment with aflibercept or bevacizumab compared with ranibizumab at 4 weeks. At 52 and 104 weeks, a greater decrease was observed in bevacizumab versus ranibizumab. Results from 2 subgroups of participants who did not receive injections within at least 1 month and 2 months before collection suggest similar changes in VEGF levels after stopping injections. It is unknown whether VEGF levels return to normal as the drug is cleared from the system or whether the presence of the drug affects the assay's ability to accurately measure free VEGF. No significant associations between VEGF concentration and systemic factors were noted.

contains references to earlier work on the tunneling states in KCl:Li.2 Previous work in this field has emphasized paramagnetic impurities. Their long spin-lattice relaxation times prevent generation of ballistic pulses of phonons and the low saturation-power levels, and weak microwave absorption compared with paraelectric systems reduces the maximum power available. See C. H. Anderson and E. S. Sabisky, Phys. Rev. Letters 21y 987 (1968), and W. J. Brya and D. E. Wagner, Phys. Rev. 157, 400 (1967), for recent progress and reference to earlier work. 3 Such bolometers can be used to detect both thermal pulses and monochromatic ultrasonic pulses.In this paper we present results on the phonon spectrum of superconducting amorphous Bi and Ga derived from tunneling measurements. The results are in the form of plots of a 2 (u))F(u>), where a 2 (w) is the energy-dependent electronphonon coupling parameter and F((*>) is the phonon density of states, with associated values of M*, the Coulomb pseudopotential. These results were obtained by inverting the strong-coupling gap equation, using the computer program of McMillan 1 which employs the experimental tunneling density of states N(u) and the superconducting energy-gap parameter \ as input data. The resulting ot 2 (u)F(u>) gives some insight into why the amorphous phases of Bi and Ga are such strong-coupling superconductors.The tunnel junctions used in this investigation were Al-Al^O^-Bi and Al -Al^Oy -Ga, and were prepared in situ in an evaporator cryostat. The Bi and Ga films were 1000 A thick and were condensed onto a substrate held at 1.5°K A brief 6 For phonons traveling under 30° from the 0-00) axis, this anisotropy in KC1 can increase the transverse velocity by 50 % while reducing the longitudinal velocity by only 10 %. 7 The original intent of this experiment was to demonstrate the monochromatic nature of the phonons by transmitting them through a scattering medium of resonant lithium ions and observing the signal to increase on application of a field that tunes the scatterers out of resonance with the phonons. Weak scattering and microwave leakage produced the opposite effect, namely a decrease of signal with electric field. 8 D. Walton, Phys. Rev. Letters JL9, 305 (1967). 9 P. P. Peressini, J. P. Harrison, and R. O. Pohl, to be published. 10 Optical resonance fluorescence is discussed in detail by W. Heitler, Quantum Theory of Radiation (Oxford University Press, London, 1966), 3rd ed., Sec. 20, case (b).description of the preparation of the tunnel junctions and of the method of measuring transition temperatures and of obtaining AQ and N(u) from the tunneling measurements have been given in an earlier publication. 2 A more detailed description of the experimental method will be included in a later article.The values of the transition temperature T c , twice the superconducting energy-gap parameter at zero temperature 2A 0 , and the ratio 2&Q/k#T c obtained for amorphous Bi and Ga in the present investigation are given in Table I, along with other values of these q...

Films of a-Si have been prepared by vacuum deposition from crucibles of BeO and BN in a hydrogen ambient. The electrical conductivity of these impure films was modified by the addition of aluminum that was coevaporated during the film deposition. The changes observed are consistent with the assumption that the aluminum doping results in a p-type film for low conconcentrations (<2.3 at.%) whereas high concentrations introduce band structure changes as well. Thickness dependent sample resistivities are observed. This result is interpreted using a layer model to approximate two surface layers with resistivities ρs = 108 Ω∙cm and a bulk layer with ρB = 8 × 103 Ω∙cm. Each high-resistance layer, which is approximately 0.12 μm thick, seems to be caused by the increased hydrogen concentration at both surfaces, which is observed in the hydrogen profiling study. It is suggested that these high-resistance surface layers are due to a wider band gap material with the Fermi level near midgap. The bulk material has a smaller band gap with the Fermi level closer to one of the band edges.

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