Impossibility to eliminate observer effect in the assessment of adherence in clinical trials.

PURPOSE: To utilize the Travoprost Dosing Aid (DA) in the assessment of patient medication adherence, while also determining whether or not altering the functionality of the DA in three randomized subject groups can reduce observer effect. METHODS: Forty-five subjects were randomized into three groups: two with monitored DAs and one without monitoring. One group of subjects was given a DA that both monitored drop usage and had visual and audible alarms, while the other monitored group included subjects given a DA that had no alarms but continued to monitor drop usage. The third group was given a DA that had no alarm reminders or dose usage monitoring. Subjects were informed that some monitors would not be functional, in an attempt to reduce observer effect, or the effect of being monitored on subject behavior and adherence. A six-item questionnaire was also utilized to assess how the subjects felt about their adherence and DA use. RESULTS: The overall adherence rates were found to be 78% in the fully functional group (95% confidence interval: 70-88) and 76% in the no alarms group (95% confidence interval: 65-89). No association was seen between questionnaire response and medication adherence. The patients in the DA group without alarms had a significantly higher odds ratio of medication adherence if they reported on the questionnaire that using the DA did affect how much they used their drops. CONCLUSION: Though the use of DA was expected to reveal different rates of adherence depending on the functionality of the DA between groups, patients with a nonfunctioning DA did not have a significant difference in medication adherence compared to those given a fully functional DA. This supports that an observer effect was not reduced despite these interventions, and that the subjects adhered to taking their medications as if they had a functioning DA and were being monitored

Non-adherence to eye care in people with diabetes

Objective Evaluate individual factors that impact adherence to eye care follow-up in patients with diabetes. Design and methods A 4-year retrospective chart review was conducted for 1968 patients with diabetes over age 40 from an urban academic center. Data collected included demographics, insurance, visual acuity, smoking status, medications, dates of dilated fundus examinations (DFE), and reported hemoglobin A1C and blood glucose levels. The primary outcome was timely DFE follow-up adherence following the initial eye exam visit. Results Overall, 41.6% of patients adhered to initial follow-up eye care recommendations. Multivariable analysis demonstrated that patients with severe diabetic retinopathy (DR) were more adherent than patients with mild DR (OR 1.86). Other variables associated with increased adherence were visual impairment and reported A1C or blood glucose. Smoking was associated with decreased adherence. Ethnicity and insurance were also significantly associated with adherence. Longitudinal follow-up rates were influenced by additional factors, including ethnicity and neighborhood deprivation index. Conclusions Patients with moderate to severe DR and/ or visual impairment were more likely to adhere to timely DFE follow-up. This could relate to the presence of visual symptoms and/or other systemic manifestations of diabetes. Smokers were less likely to adhere to timely DFE follow-up. One hypothesis is patients who smoke have other symptomatic health problems which patients prioritize over asymptomatic ocular disorders. In order to reduce vision loss from DR, practitioners should be aware that patients with mild and moderate DR, patients with normal vision, and smokers are at greater risk for poor follow-up eye care adherence. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved

Risk Assessment Challenges in the Ares I Upper Stage

NASA Marshall Space Flight Center (MSFC) is currently at work developing hardware and systems for the Ares I rocket that will send future astronauts into orbit. Built on cutting-edge launch technologies, evolved powerful Apollo and Space Shuttle propulsion elements, and decades of NASA spaceflight experience, Ares I is the essential core of a safe, reliable, cost-effective space transportation system -- one that will carry crewed missions back to the moon, on to Mars and out into the solar system. Ares I is an in-line, two-stage rocket configuration topped by the Orion crew vehicle and its launch abort system. In addition to the vehicle's primary mission -carrying crews of four to six astronauts to Earth orbit --Ares I may also use its 25-ton payload capacity to deliver resources and supplies to the International Space Station, or to "park" payloads in orbit for retrieval by other spacecraft bound for the moon or other destinations. Crew transportation to the International Space Station is planned to begin no later than 2014. The first lunar excursion is scheduled for the 2020 timeframe. This paper presents the challenges in designing the Ares I upper stage for reliability and safety while minimizing weight and maximizing performance

Common Cause Failure Modeling: Aerospace Versus Nuclear

Aggregate nuclear plant failure data is used to produce generic common-cause factors that are specifically for use in the common-cause failure models of NUREG/CR-5485. Furthermore, the models presented in NUREG/CR-5485 are specifically designed to incorporate two significantly distinct assumptions about the methods of surveillance testing from whence this aggregate failure data came. What are the implications of using these NUREG generic factors to model the common-cause failures of aerospace systems? Herein, the implications of using the NUREG generic factors in the modeling of aerospace systems are investigated in detail and strong recommendations for modeling the common-cause failures of aerospace systems are given

Controlling the properties of InGaAs quantum dots by selective-area epitaxy

Selective growth of InGaAsquantum dots on GaAs is reported. It is demonstrated that selective-area epitaxy can be used for in-plane bandgap energy control of quantum dots.Atomic force microscopy and cathodoluminescence are used for characterization of the selectively growndots. Our results show that the composition, size, and uniformity of dots are determined by the dimensions of the mask used for patterning the substrate. Properties of dots can be selectively tuned by varying the mask dimensions. A single-step growth of a thin InGaAsquantum well and InGaAsquantum dots on the same wafer is demonstrated. By using a single-step growth,dots luminescing at different wavelengths, in the range 1150–1230nm, in different parts of the same wafer are achieved.The Australian Research Council is gratefully acknowledged for the financial support

An ion-implanted InP receiver for polarization resolved terahertz spectroscopy

We report on the construction, optical alignment and performance of a receiver which is capable of recording the full polarization state of coherent terahertz radiation. The photoconductive detector was fabricated on InP which had been implanted with Fe+ ions. The device operated successfully when it was gated with near infrared femtosecond pulses from either a Ti:sapphire laser oscillator or a 1 kHz regenerative laser amplifier. When illuminated with terahertz radiation from a typical photoconductive source, the optimized device had a signal to noise figure of 100:1 with a usable spectral bandwidth of up to 4 THz. The device was shown to be very sensitive to terahertz polarization, being able to resolve changes in polarization of 0.34 degrees. Additionally, we have demonstrated the usefulness of this device for (i) polarization sensitive terahertz spectroscopy, by measuring the birefringence of quartz and (ii) terahertz emission experiments, by measuring the polarization dependence of radiation generated by optical rectification in (110)-ZnTe

Factors contributing to nonadherence to follow-up appointments in a resident glaucoma clinic versus primary eye care clinic.

PURPOSE: To determine the rate of adherence to follow-up appointment recommendations in a resident glaucoma clinic with no mechanism for reminders, compared to a resident cataract and primary eye care (CPEC) clinic in which telephone reminders were used, and to identify factors that contribute to adherence in each patient group. METHODS: This retrospective cohort study included subjects in the CPEC clinic who received telephone reminders and those in the glaucoma clinic who did not. Each sample was selected to have a similar proportion of follow-up recommendations for 1, 3, and 6 months. Subjects were considered adherent if they returned within a specified timeframe. RESULTS: A total of 144 subjects from the glaucoma clinic and 151 subjects from the CPEC clinic were included. There was no significant difference between follow-up adherence rates of patients who received telephone reminders and those who did not (odds ratio [OR] =1.35, 95% confidence interval [CI] 0.79-2.32, P=0.28). Patients who were on more than two ocular medications were more likely to return for follow-up (OR=3.11, 95% CI 1.53-6.35, P=0.0018). Subjects between the ages 50 and 80 years were more likely to be adherent compared to their younger and older peers (P=0.02). CONCLUSION: The follow-up adherence of patients in a CPEC clinic who received telephone reminders was similar to patients in a glaucoma clinic who did not receive any intervention to increase their adherence. Younger (⩽50 years old) and elderly (⩾80 years old) subjects, as well as patients using less than two glaucoma medications, were less likely to adhere to their follow-up appointments

Zn3As2 Nanowires and nanoplatelets: highly efficient infrared emission and photodetection by an earth abundant material

The development of earth abundant materials for optoelectronics and photovoltaics promises improvements in sustainability and scalability. Recent studies have further demonstrated enhanced material efficiency through the superior light management of novel nanoscale geometries such as the nanowire. Here we show that an industry standard epitaxy technique can be used to fabricate high quality II-V nanowires (1D) and nanoplatelets (2D) of the earth abundant semiconductor Zn3As2. We go on to establish the optoelectronic potential of this material by demonstrating efficient photoemission and detection at 1.0 eV, an energy which is significant to the fields of both photovoltaics and optical telecommunications. Through dynamical spectroscopy this superior performance is found to arise from a low rate of surface recombination combined with a high rate of radiative recombination. These results introduce nanostructured Zn3As2 as a high quality optoelectronic material ready for device exploration.T.B., P.C., Y.G., H.H.T., and C.J. acknowledge the Australian Research Council. T.B., P.C., Y.G., H.H.T., and C.J. thank the Australian National Fabrication Facility for access to the growth and microscopy facilities and Centre for Advanced Microscopy and Australian Microscopy and Microanalysis Research Facility for access to microscopy facilities used in this work. Y.W., B.B., H.E.J., and L.M.S. acknowledge the financial support of the National Science Foundation through grants DMR-1105362, 1105121, and ECCS-1100489

Direct imaging of the spatial diffusion of excitons in single semiconductor nanowires

We use spatially and temporally resolved photoluminescence to measure excitondiffusion in single zinc blende GaAs/AlGaAs core/shell and mixed phase InPnanowires.Excitons in the single phase GaAs/AlGaAs nanowires are seen to diffuse rapidly throughout the nanowire with a measured diffusion constant ranging from 45 to 100 cm²/s, while in the mixed phase, InPnanowireelectrons and holes are seen to rapidly localize to the quantum confined states in the zinc blende and wurtzite segments, respectively. The diffusion constant in the GaAs/AlGaAs nanowire is similar to the best hole mobilities observed in modulation doped heterostructures.We acknowledge the financial support of the National Science Foundation through grants DMR-0806700, 0806572, 1105362, 1105121, and ECCS-1100489, and the Australian Research Council