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Background: This study aimed to investigate the risk of Parkinson's disease (PD) among patients with age-related macular degeneration (AMD) and its association with confounding comorbidities., Methods: A population-based retrospective cohort study was conducted using Longitudinal Health Insurance Database 2000 (LHID2000). We established AMD and non-AMD cohorts from January 1, 2000 to December 31, 2012 to determine the diagnosis of PD. A total of 20,848 patients were enrolled, with 10,424 AMD patients and 10,424 controls matched for age, sex, and index year at a 1:1 ratio. The follow-up period was from the index date of AMD diagnosis to the diagnosis of PD, death, withdrawal from the insurance program, or end of 2013. Multivariable Cox regression analysis was performed to examine the hazard ratio (HR) and 95% confidence interval (CI) for the risk of PD between the AMD and non-AMD cohorts., Result: After adjusting for potential confounders, there was a higher risk of developing PD in the AMD cohort than in the non-AMD cohort (adjusted HR = 1.35, 95% CI = 1.16-1.58). A significant association could be observed in both female (aHR = 1.42, 95% CI = 1.13-1.80) and male (aHR = 1.28, 95% CI = 1.05-1.57) patients, aged more than 60 years (60-69: aHR = 1.51, 95% CI = 1.09-2.09, 70-79: aHR = 1.30, 95% CI = 1.05-1.60; 80-100: aHR = 1.40, 95% CI = 1.01-1.95), and with more than one comorbidity (aHR = 1.40, 95% CI = 1.20-1.64). A significant association between increased risk of PD and AMD was observed among patients with comorbidities of osteoporosis (aHR = 1.68, 95% CI = 1.22-2.33), diabetes (aHR = 1.41, 95% CI = 1.12-1.78) and hypertension (aHR = 1.36, 95% CI = 1.15-1.62) and medications of statin (aHR = 1.42, 95% CI = 1.19-1.69) and calcium channel blocker (CCB) (aHR = 1.32, 95% CI = 1.11-1.58). The cumulative incidence of PD was significantly higher over the 12-year follow-up period in AMD cohort (log-rank test, p < 0.001)., Conclusions: Patients with AMD may exhibit a higher risk of PD than those without AMD., (© 2021. The Author(s).)

We present experimental results of reflectance and transmittance measurements of infrared radiation by high-density photogenerated free carriers in polycrystalline germanium, polycrystalline silicon, and chemical vapor deposition zinc selenide windows. Linearly polarized 1064 and 532 nm wavelength light from a Nd:YAG laser with a 130 ps pulse width were used to generate free carriers in the samples. Reflectance and transmittance were measured at a 10.6 microm wavelength using a linearly polarized CO2 laser.

We present a new infrared (IR) detection scheme based on the infrared quantum counter (IRQC) detector and utilizing the photon avalanche process. At the time of its discovery, the phenomenon of photon avalanche was considered a limitation rather than an advantage for the development of IRQC. Both the experimental results and the numerical modeling presented demonstrate that the process responsible for photon avalanche can be used to enhance the detection of an IR signal. A new room-temperature IR detection scheme is proposed on the basis of the results of this research. The novel detection scheme presented demonstrates an increase in detectivity and a decrease in the noise-equivalent power when compared with the IRQC schemes previously discussed in the literature.

Experimental results are presented for 1,800 contra-directional two-beam coupling (TBC) measurements in a single crystal fiber of LiNbO8:Fe using a single incident beam and its Fresnel reflection off the back surface of the fiber. To our knowledge, this is the first time that volume gratings have been written in a fiber using this beam coupling geometry. At small f-numbers, the TBC efficiency has been predicted to decrease in bulk LiNbO3:Fe due to the erasure of the weak gratings by the dark conductivity. We present experimental results validating the published theory and show experimentally that confinement of the interfering beams in a fiber geometry overcomes this limitation.

We report on the near-infrared absorption, emission, and lifetime data of Cr(4+):Lu(3)Al(5)O(12) (Cr:LAG) and compare the results with the known laser material Cr(4+)-doped Y(3)Al(5)O(12) (Cr:YAG). Lu(3)Al(5)O(12) has a smaller unit cell than Y(3)Al(5)O(12), and this feature is reflected in its spectroscopic properties. The low-temperature luminescence spectrum is shifted by 85 cm(-1) to higher energy compared with Cr:YAG. The luminescence lifetime of Cr:LAG at 10 K is 28.7 micros (Cr:YAG, 30.6 micros) and at 300 K is 4.3 micros (Cr:YAG, 3.5 micros). From these lifetimes we postulate that the quantum efficiency in Cr:LAG is higher than in Cr:YAG. We discuss the potential of Cr:LAG as a tunable near-infrared laser.

Four paper-and-pencil spatial tests, measuring two- and three-dimesional spatial visualization and spatial orientation, were administered to 2508 Caucasian high-school students. Sibling correlations and within-sex score distributions were examined for the influence of a major sex-linked gene. Sex-linked influences were most clear on the test of two-dimensional visualization and on an average of the standard scores on all the tests. For those tests best fitting the genetic model, estimates of the frequency of the recessive gene (contributing to good performance) we-re near 0.45. There was evidence of incomplete dominance in females. Environmental or non-sex-linked genetic factors influenced spatial performance but did not systematically improve performance with age.

Monochromatic light was provided by a continuous wave Argon ion laser. We chose to study the in vitro effects of light at 457.9, 465.8, 476.5, 488.0, 501.7, and 514.5 nm as representative of a reasonably evenly spaced sampling across the blue-green spectrum. The in vivo experiments were conducted at 457.9, 476.5, 488.0, and 514.5 nm. In vitro light at 488.0 nm appeared to be more effective than the others studied. After 24 h of irradiance, the in vivo decline in serum bilirubin concentration produced by light at 488.0 nm was one-and-one-half, two, and four times as effective as light at 457.9, 476.5 and 514.5 nm, respectively. By 48 h of exposure, the declines produced by light at 457.9 nm and 488.0 nm are significantly superior to that at 476.5 nm and 514.5 nm, but they do not differ from one another.

Advantages of pressure scanning over other methods of tuning the wavelength of dye lasers are discussed. The construction of a pressure scanned high resolution dye laser is described. The laser has a scan range of more than 40 cm(-1) in its intermediate resolution mode, an improvement on the order of a hundredfold over previous methods of tuning. Preliminary tests have indicated a scan range of 4 cm(-1) in the high resolution mode. As a demonstration of its applicability and versatility, the laser was used to xesolve the ground state splitting of the chromium isotopes in ruby.

We have investigated the spectroscopic properties of a crystalline sapphire fiber unintentionally doped with Cr(3+). We find that tensile stress produces blue shifts of the R lines and changes in their radiative lifetimes and integrated intensities that can be correlated to stress-induced changes of the crystal-field parameters.

The hypothesis that sex differences in field independence and mental arithmetic can be accounted for by sex differences in spatial ability was supported for a group of 46 female and 35 male undergraduates. Sex-typing does not appear to be strongly related to spatial ability for either sex. There is a possibility of the existence of a field-independence trait independent of spatial ability, particularly among females; however, if such a trait does exist there do not appear to be significant sex differences with respect to it. Factor analysis indicates that tests of spatial ability, field independence, and mental arithmetic emerge together in a spatial ability factor. Sex differences in the factor structure of nine measures, most of which typically display sex differences (spatial ability, field independence, mental arithmetic, vocabulary, verbal and nonverbal creativity, femininity, and achievement motivation) were largely the result of differences with respect to a spatial factor.

A sapphire disk is used as a variable birefringent beam splitter for the linearly polarized pump beam in an oscillator-amplifier dye laser system. Rotation of the disk varies the extent of retardation. The induced elliptical polarization results in a variable back surface reflectance between approximately 0.02-0.15 for the green spectral region. Reflectances are measured on two disks with different thicknesses and compared with an approximate model describing the reflectance as a function of angle of rotation of the disk.

We have employed a purely optical method to measure spin-lattice relaxation in the lower excited (4)S(3/2) state of Er(3+) in LaF(3) at helium temperatures. Above 3 K the relaxation is dominated by an Orbach process through the upper (4)S(3/2) state. Below 3 K the relaxation is caused by some residual mechanism that obscures the Kramers-Van Vleck direct process. By relating the Orbach relaxation measurements to the homogeneous broadening of the upper (4)S(3/2) level, we determine values of the transition rates between the upper and lower (4)S(3/2) states.

A tunable jet-stream dye laser pumped by a cavity-dumped argon laser has been synchronized to a photoelastic modulator to measure magnetic circular dichroism. Gated signal amplification takes advantage of the laser's pulsed operation to detect weak dichroic signals. Comparative data show that the dye laser and gated amplification give a SNR better than that obtained with the previously used lamp, monochromator, and lockin detector. Other applications of the dye laser and gated amplification are discussed.

The paper-and-pencil spatial performance of right- and left-handed high school students was compared separately for 1236 males and 1241 females. Handedness differences in favor of right-handed subjects were found among males only. Analysis of data for a subgroup of 555 subjects indicated that handedness and sex-linked genetic effects acted independently and additively on spatial performance.