Efficacy and Safety of Intravitreal Gene Therapy for Leber Hereditary Optic Neuropathy Treated within 6 Months of Disease Onset

Purpose: To evaluate the efficacy of a single intravitreal injection of rAAV2/2-ND4 in subjects with visual loss from Leber hereditary optic neuropathy (LHON). Design: RESCUE is a multicenter, randomized, double-masked, sham-controlled, phase 3 clinical trial. Participants: Subjects with the m.11778G>A mitochondrial DNA mutation and vision loss ≤6 months from onset in 1 or both eyes were included. Methods: Each subject's right eye was randomly assigned (1:1) to treatment with rAAV2/2-ND4 (single injection of 9 × 1010 viral genomes in 90 μl) or to sham injection. The left eye received the treatment not allocated to the right eye. Main Outcome Measures: The primary end point was the difference of the change from baseline in best-corrected visual acuity (BCVA) between rAAV2/2-ND4–treated and sham-treated eyes at week 48. Other outcome measures included contrast sensitivity, Humphrey visual field perimetry, retinal anatomic measures, and quality of life. Follow-up extended to week 96. Results: Efficacy analysis included 38 subjects. Mean age was 36.8 years, and 82% were male. Mean duration of vision loss at time of treatment was 3.6 months and 3.9 months in the rAAV2/2-ND4–treated eyes and sham-treated eyes, respectively. Mean baseline logarithm of the minimum angle of resolution (logMAR) BCVA (standard deviation) was 1.31 (0.52) in rAAV2/2-ND4–treated eyes and 1.26 (0.62) in sham-treated eyes, with a range from −0.20 to 2.51. At week 48, the difference of the change in BCVA from baseline between rAAV2/2-ND4–treated and sham-treated eyes was −0.01 logMAR (P = 0.89); the primary end point of a −0.3 logMAR (15-letter) difference was not met. The mean BCVA for both groups deteriorated over the initial weeks, reaching the worst levels at week 24, followed by a plateau phase until week 48, and then an improvement of +10 and +9 Early Treatment Diabetic Retinopathy Study letters equivalent from the plateau level in the rAAV2/2-ND4–treated and sham-treated eyes, respectively. Conclusions: At 96 weeks after unilateral injection of rAAV2/2-ND4, LHON subjects carrying the m.11778G>A mutation treated within 6 months after vision loss achieved comparable visual outcomes in the injected and uninjected eyes

Predicting solar cell performance from terahertz and microwave spectroscopy

Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Here, the expertise from fifteen laboratories is combined to quantitatively model the current-voltage characteristics of a solar cell from such measurements. To this end, the impact of measurement conditions, alternate interpretations, and experimental inter-laboratory variations are discussed using a (Cs,FA,MA)Pb(I,Br)3 halide perovskite thin-film as a case study. At 1 sun equivalent excitation, neither transport nor recombination is significantly affected by exciton formation or trapping. Terahertz, microwave, and photoluminescence transients for the neat material yield consistent effective lifetimes implying a resistance-free JV-curve with a potential power conversion efficiency of 24.6 %. For grainsizes above ≈20 nm, intra-grain charge transport is characterized by terahertz sum mobilities of ≈32 cm2 V−1 s−1. Drift-diffusion simulations indicate that these intra-grain mobilities can slightly reduce the fill factor of perovskite solar cells to 0.82, in accordance with the best-realized devices in the literature. Beyond perovskites, this work can guide a highly predictive characterization of any emerging semiconductor for photovoltaic or photoelectrochemical energy conversion. A best practice for the interpretation of terahertz and microwave measurements on photovoltaic materials is presented

DOE-NSF-NIH Workshop on Opportunities in THz Science, February 12-14, 2004

This is the report of the Workshop on Opportunities in THz Science, held on February 12-14, 2004 in Arlington, VA. This workshop brought together researchers who use or produce THz radiation for physics, chemistry, biology, medicine, and materials science to discuss new research opportunities and common resource needs. The charge from the sponsors of the workshop was to focus on basic science questions within these disciplines that have and can be answered using THz radiation

Charge Carrier Dynamics and Mobility Determined by Time-Resolved Terahertz Spectroscopy on Films of Nano-to-Micrometer-Sized Colloidal Tin(II) Monosulfide

Tin­(II) monosulfide (SnS) is a semiconductor material with an intermediate band gap, high absorption coefficient in the visible range, and earth abundant, nontoxic constituent elements. For these reasons, SnS has generated much interest for incorporation into optoelectronic devices, but little is known concerning the charge carrier dynamics, especially as measured by optical techniques. Here, as opposed to prior studies of vapor deposited films, phase-pure colloidal SnS was synthesized by solution chemistry in three size regimes, ranging from nanometer- to micrometer-scale (SnS small nanoparticles, SnS medium 2D nanosheets, and SnS large 2D μm-sheets), and evaluated by time-resolved terahertz spectroscopy (TRTS); an optical, noncontact probe of the photoconductivity. Dropcast films of the SnS colloids were studied by TRTS and compared to both thermally annealed films and dispersed suspensions of the same colloids. TRTS results revealed that the micrometer-scale SnS crystals and all of the annealed films undergo decay mechanisms during the first 200 ps following photoexcitation at 800 nm assigned to hot carrier cooling and carrier trapping. The charge carrier mobility of both the dropcast and annealed samples depends strongly on the size of the constituent colloids. The mobility of the SnS colloidal films, following the completion of the initial decays, ranged from 0.14 cm²/V·s for the smallest SnS crystals to 20.3 cm²/V·s for the largest. Annealing the colloidal films resulted in a ∼20% improvement in mobility for the large SnS 2D μm-sheets and a ∼5-fold increase for the small nanoparticles and medium nanosheets