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28th European Photovoltaic Solar Energy Conference and Exhibition; 324-326, In this investigation Lumogen Red dye and a Europium complex (Eu(tta)3phen), a combination two-dopant luminescent solar concentrator, LSC, is proposed for building integrated LSC-window applications where a high visible transmittance is required. Such applications may include integration of LSC with photovoltaic-powered smart windows. Smart window glasses change its state from transparent to opaque in the presence of applied voltage from PV/LSC devices. Use of this low cost highly transparent LSC reduces the solar cell material and thus the cost of the system. The Lumogen Red dye absorbs over 400 to 600 nm and emits at 500 to 700nm. The Eu(tta)3phen absorption is complementary to the Eu complex, absorbing over 300 to 400nm. Critically the Eu(tta)3phen has a large Stokes shift, emitting at >600nm, thereby greatly avoiding the problem of re-absorption in the multi-dye LSCs. Moreover, the Eu complex is not absorbing in the visible range and, hence, overall high transmission is maintained with its addition to the LSC. A crystalline silicon (c-Si) edge-collecting solar cell of 0.36 cm2 is used to compare the electrical output of Lumogen Red LSCs with and without the Eu complex. A significant enhancement in the Jsc (45%), has been measured in high transparency windows (T ~86%) with addition of Eu(tta)3Phen relative to Lumogen Red only. In windows with lower optical transparency (T is ~68%), the gain in Jsc from adding Eu(tta)3Phen was by 17% with addition of Eu(tta)3Phen, relative to Lumogen Red only.

Time-resolved spectra of the decay of the O2 infrared atmospheric ( a¹Δg → X³Σg−) ( 0,0) band emission in the evening twilight at 41.7°N have been obtained using the Fourier transform infrared (FTIR) technique. The measurements were made during a two-month summer-fall period which included the autumnal equinox. The late twilight variations were well described by single exponentials with decay time constants which ranged from (44.4±1.6) min in early August to (61.1±2.1) min near the equinox. In this connection, a strong positive trend in the time constant was observed during late August and early September. When combined with available data for collisional quenching and for fall-winter, upper-mesospheric altitude distributions of O2 (a¹Δg, ν=0) in the late twilight, these observations support a radiative lifetime of about one hour.

Two Fourier transform spectrometers have been used to investigate the properties of the near-infrared hydroxyl (OH) nightglow emission under high-latitude summertime conditions and any association with noctilucent clouds (NLCs). The measurements were made from Poker Flat Research Range, Alaska (65.1°N, 147.5°W), during August 1986. Simultaneous photographic observations of the northern twilight sky were made from Gulkana, Alaska (62.2°N, 145.5°W), approximately 340 km to the south to establish the presence of NLCs over the spectrometer site. Data exhibiting significant short-term variations in the relative intensity (as much as 50–100%) and rotational temperature (typically 5–15 K) were recorded on six occasions when NLCs were observed. Joint measurements were also obtained on several "cloud-free" nights. No obvious relationship was found linking the mean OH intensity or its variation with the occurrence of NLCs. However, a clear tendency was found for the mean OH temperature to be lower on NLC nights than on cloud-free nights. In particular, a significant fraction of the OH(3–1) band spectra recorded by each instrument (16–57%) exhibited temperatures below ~154 K on NLC nights compared with

In 2002, the Sounding of the Atmosphere us- ing Broadband Emission Radiometry (SABER) instru- ment aboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite went online and has since been providing radiometric data concern- ing the mesosphere and lower thermosphere/ionosphere (MLTI) region of the atmosphere. Researchers at the Utah State University NASA Space Grant Consortium have been tasked with validating measurements of the hydroxyl airglow volume emission rates (VER) taken by SABER. To this end, we compare SABER measurements of the altitude distribution of hydroxyl airglow to mea- surements taken by photometers aboard rockets launched between 1961 and 1986 that were catalogued in 1988 by Baker and Stair [1]. We select for comparison SABER scans taken near these launch sites at the same time of year, and at similar solar zenith angles. We then plot the selected SABER altitude profiles alongside renormalized rocket photometer profiles. Important considerations for comparison are the mean thickness of emission layers, the mean altitude of their centers, and relative numbers of bifurcated airglow emission layers, which manifest as altitude profiles with two or more peaks.

PV cell efficiency is limited partly due to the spectral mismatch between the solar spectrum and the PV absorption properties. PV conversion efficiency is enhanced by external modulation of the incident irradiance, by means of photon downshifting (DS) and upconversion (UC). A ray-trace modelling tool is presented to simulate the luminescent DS and UC processes and thereby optimise the doping concentrations and geometric dimensions of the DS and UC layers.

In this investigation Naphtalimide based Lumogen Violet organic dye [BASF] is characterized for inclusion in luminescent downshifting (LDS) layers. A PV device made up of an LDS layer of Lumogen Violet deposited on top of a crystalline silicon cell has been fabricated to improve its power conversion efficiency. External quantum efficiency measurements and outdoor tests for the PV/LDS devices are discussed. An analytical model was also developed to compare experiment results with the model predictions.

27th European Photovoltaic Solar Energy Conference and Exhibition; 500-502, PV cell efficiency is limited partly due to the spectral mismatch between the solar spectrum and the PV absorption properties. PV conversion efficiency is enhanced by external modulation of the incident irradiance, by means of photon downshifting (DS) and upconversion (UC). A ray-trace modelling tool is presented to simulate the luminescent DS and UC processes and thereby optimise the doping concentrations and geometric dimensions of the DS and UC layers.

The efficacy and safety of prolonging prophylaxis for venous thromboembolism in medically ill patients beyond hospital discharge remain uncertain. We hypothesized that extended prophylaxis with apixaban would be safe and more effective than short-term prophylaxis with enoxaparin. METHODS: In this double-blind, double-dummy, placebo-controlled trial, we randomly assigned acutely ill patients who had congestive heart failure or respiratory failure or other medical disorders and at least one additional risk factor for venous thromboembolism and who were hospitalized with an expected stay of at least 3 days to receive apixaban, administered orally at a dose of 2.5 mg twice daily for 30 days, or enoxaparin, administered subcutaneously at a dose of 40 mg once daily for 6 to 14 days. The primary efficacy outcome was the 30-day composite of death related to venous thromboembolism, pulmonary embolism, symptomatic deep-vein thrombosis, or asymptomatic proximal-leg deep-vein thrombosis, as detected with the use of systematic bilateral compression ultrasonography on day 30. The primary safety outcome was bleeding. All efficacy and safety outcomes were independently adjudicated. RESULTS: A total of 6528 subjects underwent randomization, 4495 of whom could be evaluated for the primary efficacy outcome - 2211 in the apixaban group and 2284 in the enoxaparin group. Among the patients who could be evaluated, 2.71% in the apixaban group (60 patients) and 3.06% in the enoxaparin group (70 patients) met the criteria for the primary efficacy outcome (relative risk with apixaban, 0.87; 95% confidence interval [CI], 0.62 to 1.23; P = 0.44). By day 30, major bleeding had occurred in 0.47% of the patients in the apixaban group (15 of 3184 patients) and in 0.19% of the patients in the enoxaparin group (6 of 3217 patients) (relative risk, 2.58; 95% CI, 1.02 to 7.24; P = 0.04). CONCLUSIONS: In medically ill patients, an extended course of thromboprophylaxis with apixaban was not superior to a shorter course with enoxaparin. Apixaban was associated with significantly more major bleeding events than was enoxaparin, Supported by Bristol-Myers Squibb and Pfizer

This paper is a review of the historical development of the Michelson interferometer into modern-day Fourier transform spectrometry (FTS) used for upper atmospheric emission studies in the near IR. For the period of the last decade, the focus of the review is upon USAF/USU interferometric instruments. Michelson invented the "cross beam" interferometer in 1880; however, the first interferogram was not reported until that of Wood in 1911. Fellgett deduced the multiplex advantage in 1949. By the early 1950s, both Jacqui-not and Rupert had pointed out the throughput advantage, and Fellgett and Strong had each obtained Fourier transforms of interferograms. In 1959, J. Connes and Gush obtained a spectrum of the nighttime IR airglow in 30 min using a Michelson interferometer. In 1962 Gush and Buijs flew an interferometer aboard a balloon to obtain spectra from the airglow. Mertz and M. Block developed a commercial Michelson interferometer in about 1959. L. Block of AFCRL flew a Michelson interferometer aboard a satellite in 1962. In 1965, Connes and Connes obtained high-resolution spectra of planets using cat's-eye retroreflectors coupled with an interferometrically controlled step and integrate method. NASA successfully flew an interferometer aboard a satellite in 1969, which led to including FTS experiments on the planetary probes. In 1965 Tukey and Cooley published their FFT computer program based upon the algorithm of Good. AFGL/USU applied the FFT algorithm to FTS that same year. Stair launched a rocketborne liquid-He cooled interferometer in 1976 which obtained spectra of earth limb emissions. Mertz in 1959 approached field-of-view widening of an interferometer using variable thickness glass compensator plates. Baker and his USU staff used the Connes-Bouchareine compensation method to develop a series of wide-angle Michelson interferometers (WAMIs) for airglow and auroral studies. In 1973, they created a cryogenic WAMI to obtain an IR airglow spectrum in only 10 sec. A rocketborne version was successfully flown to obtain airglow spectra in 1979. This instrument took a 2-cm(-1) interferogram in 1 sec., used a liquid-He cooled detector to cover the 2-8-microm range, and the NESR was 3 x 10(-13) W cm(-2) sr(-1)/cm(-1) at 5 microm.

The rayleigh, originally defined as a unit to express the total column light emission rate [10(10) photons sec(-1) (m(2)column) (-1)] can equivalently be defined as a unit for apparent photon radiance ((1/4)pi 10(10) photons sec(-1) m(-2) sr(-1)). The selection of the appropriate definition will depend upon the physical situation and the interests of the user. The applicability of the unit for expressing the quantitative measurement of all extended light sources, including optically thick media, is both handy and valid.

The design of a field-of-view-widened interferometer for airglow survey work is discussed, and some preliminary airglow results are presented. The 4.5-cm aperture optics of the interferometer give a very large throughput gain compared with a conventional slit spectrometer. In addition, by using optical wedge compensators, the field of view is widened to over 5 degrees full angle, resulting in a field-widened throughput gain of approximately 100 compared with a standard Michelson interferometer of the same aperture size. Digital recording is used to achieve sufficient dynamic range and to aid in computation of the fast fourier transforms. A series of airglow spectra of the midlatitude sky in the spectral region from 0.6 micro to 0.9 micro down to a resolution of about 2 A are given for a sunset transition and also at night. Bright features are the vibration-rotation hydroxyl emission bands and the oxygen red lines. Particularly interesting are enhancement of these emissions during twilight and the observation of what may be vibrationally excited O(2) in the lower atmosphere.

A technique for obtaining emission cross sections in laboratory beam studies is presented, including effects on the cross section due to polarization of the emitted light. Systematic analytical errors arising from optical problems are analyzed and evaluated for a typical spectral feature. The primary sources of error are shown to arise from the particular geometry used in the optical measurements, the variation of the calibrating light source over the bandwidth of the emission feature, and the variation of the responsivity of the optical system over the bandwidth.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 830-833, Organic cells and dye-sensitized cells developed to-date have a narrow active absorption range, relative to the spectral range of the available solar resource. Their efficiency could be significantly enhanced through a process of down-shifting (DS) and up-conversion of non-absorbable photons converting them to photons better matching the spectral response of the particular solar cell. The DS molecules must exhibit a large Stokes shift and high luminescent quantum yield when incorporated in the downshifting polymer layer. In this paper, the QY of a downshifting Europium (III) complex in solution is determined using two distinct experimental techniques. The QY is measured for varying concentration and at varying excitation wavelength.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 759-762, We have studied the excitation rate of Lumogen Red dye molecules by enhanced local electromagnetic field of Au nanoparticles for thin film luminescent solar concentrator (LSCs).The localized enhanced electromagnetic field of Au nanoparticles leads to an increase the excitation rate, and consequently in emission rate of dye molecules. By varying the distance between Au nanoparticles and dye film we showed transition form quenching to enhancement in edge emission and resultant ISC current output of thin film LSCs. When dye molecules were placed in the range of enhanced electromagnetic field of Au nanoparticles. Two competing factors affected the edge emission of thin film LSC; increased excitation rate (by enhanced local electromagnetic field of Au nanoparticles) and distance between Au nanoparticles and dye molecules.

A low light TV camera co-aligned with a narrow field Michelson interferometer have been used to investigate how variations in the intensity and temperature of the near infrared hydroxyl nightglow emission are related to the passage of short period mesospheric gravity waves. The observations were made from Sacramento Peak, NM (32.8°N, 105.8°W) on the night of 14/15 June 1983, during a spectacular nightglow display that also exhibited wave structure visible to the dark adapted eye. A coherent wave-like pattern of horizontal wavelength 23 ± 1 km moving uniformly with a velocity of 28 ± 2 m s −1 (apparent period 13.7 ± 1.2 min), was measured at several azimuths over an interval of 2.5 h. The induced intensity and temperature perturbations were wave-like in nature and exhibited a high degree of correlation. The intensity variations were large, up to 30%, yet the brightest wave forms were ⩽ 10 K hotter than the adjacent dark forms. The amplitude of the intensity fluctuation was found to be ∼ 8 times larger than the temperature variation. In all cases the intensity wave led the thermal wave, but only by a small amount. High contrast wave patterns of this type are uncommon and are a principal feature of “bright night” displays.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 390-393, A previously developed Monte-Carlo ray-trace model has been modified to incorporate multiple luminescent species. Liquid luminescent solar concentrators (LSCs) have been fabricated to verify the ray-trace predictions for LSCs containing multiple luminescent dyes. Single dye and multiple dye solutions of varying concentrations can be easily prepared and inserted into the experimental liquid LSC setup. In this way, experimental uncertainties, such as reduction in the luminescent quantum yield, can be reduced. Hence, the spectral effects of various single and multiple dyes can be analysed and compared more accurately with ray-trace predictions. Initial results from the liquid LSC characterisation and comparison with model predictions are presented here.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 334-337, The electrical and spectral output from luminescent solar concentrator (LSC) devices is predicted using thermodynamic modelling and ray-trace modelling techniques. Predicted output from four LSCs of varying dimensions, containing different luminescent dyes, are found to be in good agreement with measured output taken from fabricated LSCs. Despite the many different processes involved in the two modelling approach, predicted short circuit current densities from both approaches are found to be in excellent agreement.

Objective The Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) Study is examining the effects of long-term fibrate therapy on coronary heart disease (CHD) event rates in patients with diabetes mellitus. This article describes the trial's run-in phase and patients' baseline characteristics. Research design and methods FIELD is a double-blind, placebo-controlled trial in 63 centres in 3 countries evaluating the effects of fenofibrate versus placebo on CHD morbidity and mortality in 9795 patients with type 2 diabetes mellitus. Patients were to have no indication for lipid-lowering therapy on randomization, but could start these or other drugs at any time after randomization. Follow-up in the study was to be for a median duration of not less than 5 years and until 500 major coronary events (fatal coronary heart disease plus nonfatal myocardial infarction) had occurred. Results About 2100 patients (22%) had some manifestation of cardiovascular disease (CVD) at baseline and thus high risk status. Less than 25% of patients without CVD had a (UKPDS determined) calculated 5-year CHD risk of 30), most were men, two-thirds were aged over 60 years, and substantial proportions had NCEP ATP III features of the metabolic syndrome independent of their diabetes, including low HDL (60%), high blood pressure measurement or treatment for hypertension (84%), high waist measurement (68%), and raised triglycerides (52%). After a 6-week run-in period before randomisation with all participants receiving 200 mg comicronized fenofibrate, there were declines in total and LDL cholesterol (10%) and triglycerides (26%) and an increase in HDL cholesterol (6.5%). Conclusion The study will show the effect of PPAR-alpha agonist action on CHD and other vascular outcomes in patients with type 2 diabetes including substantial numbers with low to moderate CVD risk but with the various components of the metabolic syndrome. The main results of the study will be reported in late 2005.

To characterize CMOS imagers an LED-based multi-spectral optical source system was designed and tested which is capable of illuminating a 15-mm field at a conjugate distance of 50 mm with 98 percent uniformity. The calibration source is comprised of an array of RGB semiconductor LEDs, an IR cutoff filter and a diffusing lens. The system is integrated into an anodized aluminum housing. The spatial uniformity of the LED optical source was compared with an optical integrating sphere and an Optoliner projection system.

To evaluate the role of surgical exploration and repair of the inguinal canal in athletes suspected of having a sports hernia.Thirty-five (34 males, 1 female) athletes with a suspected sports hernia underwent surgical exploration and inguinal hernia repair. After six months, all athletes were sent questionnaires to assess any improvement in analogue pain scores, return to sport, recurrence of symptoms and the overall result of surgery.Operative findings revealed a tear in the external oblique aponeurosis with or without a significant posterior bulge (n=20), a lone significant posterior bulge (n=10), a tear in the conjoint tendon with dilated superficial ring (n=3), small direct hernial sac (n=1) and lipoma of the spermatic cord (n=1). Surgery consisted of repair of external oblique tear (when present) and prolene darn or lichtenstein mesh repair of the posterior inguinal canal. Twenty-seven patients replied to the questionnaire giving a response rate of 78%; of these, 25 patients (93%: 95% CI 83-100) had returned to normal athletic activities at pre-injury level. There was a marked improvement in level of pain (median pain level=8 pre-operative vs 2 post-operative, p0.001). Eleven patients (41%) rated the results as excellent, eleven (41%) as good and five (18%) as fair and none worse. Six patients complained of occasional discomfort related to the scar. Three patients complained of recurrence of their symptoms after 4 to 5 months following strenuous exercise.Sports hernia presents with a spectrum of surgical findings. Athletes with sports hernia should be considered for routine hernia repair, as the majority of the patients benefit from surgery. It is important to offer a structured rehabilitation programme to maximise the benefits of surgery.

The application of principal components analysis (PCA) to multispectral satellite images is a routine way to present the data in false-color composite images. These composite images include a very high percentage of available information and have no correlation between the displayed colors. PCA routines are included in commercial GIS software, and custom algorithms are in wide use.This paper describes an early application of a new, genetic algorithm based, PCA routine. Landsat data for an Idaho farm were evaluated for temporal changes using this new algorithm, and the eigenvalues consistently converged with excellent results.