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Zero electron kinetic energy (ZEKE) spectroscopy is employed to gain information on the vibrational energy levels of the para-fluorotoluene (pFT) cation. Vibrationally resolved spectra are obtained following excitation through a range of intermediate vibrational energy levels in the S1 state. These spectra allow the observation of different cationic vibrational modes, whose assignment is achieved both from a knowledge of the S1 vibrational states and also by comparison with density functional calculations. In one notable case, clean ZEKE spectra were obtained from two overlapped S1 features. From the authors' data, the adiabatic ionization energy of pFT was derived as 70 946±4 cm-1. The information on the cationic energy levels obtained will be useful in untangling the intramolecular vibrational redistribution dynamics of pFT in the S1 state. [ABSTRACT FROM AUTHOR]

We employ zero-kinetic-energy (ZEKE) photoelectron spectroscopy with nanosecond laser pulses to study intramolecular vibrational redistribution (IVR) in S1 para-fluorotoluene. The frequency resolution of the probe step is superior to that obtained in any studies on this molecule to date. We focus on the behavior of the 131 (C–CH3 stretch) and 7a1 (C–F stretch) vibrational states whose dynamics have previously received significant attention, but with contradictory results. We show conclusively that, under our experimental conditions, the 7a1 vibrational state undergoes significantly more efficient IVR than does the 131 state. Indeed, under the experimental conditions used here, the 131 state undergoes very little IVR. These two states are especially interesting because their energies are only 36 cm-1 apart, and the two vibrational modes have the same symmetry. We discuss the role of experimental conditions in observations of IVR in some detail, and thereby suggest explanations for the discrepancies reported to date. [ABSTRACT FROM AUTHOR]

We have prepared a coherent superposition of the two components of a Fermi resonance in the S1 state of toluene at ∼460 cm-1 with a ∼1 ps laser pulse and monitored time-resolved photoelectron velocity-map images. The photoelectron intensities oscillate with time in a manner that depends on their kinetic energy, even though full vibrational resolution in the cation is not achieved. Analysis of the time-dependent photoelectron spectra enables information on the composition of the S1 wavepacket to be deduced. Such an experiment, in which a whole set of partially dispersed cation vibrational states are detected simultaneously, suggests an efficient method of studying intramolecular vibrational energy redistribution processes in excited states. [ABSTRACT FROM AUTHOR]

Few environmental risk factors are known for glaucoma, in contrast to other common age‐related eye diseases such as AMD and cataract. With the advent of genome‐wide association studies (GWAS), we are increasingly understanding the importance of genetic factors influencing risk of glaucoma. This presentation will discuss results from the largest GWAS of intraocular pressure from the UK Biobank study of over 100 000 people, showing that ~700 common genetic risk variants can predict risk of glaucoma, with an AUC (area under the curve) for high‐tension glaucoma of 0.75 and for normal tension glaucoma of 0.70. Pharmacogenomics is an increasingly important arena, and I will present novel work in large population‐based studies exploring the prediction of response to prostaglandin agonists using genetics. The International Glaucoma Genetics Consortium GWAS of over 30 000 people with glaucoma and 300,000 controls is currently being analysed and preliminary results will be discussed. [ABSTRACT FROM AUTHOR]

An abstract of the article "Prevalence of Myopia and Association With Education in Europe," by Katie M. Williams and Chris J. Hammond is presented.

The article provides an account of basic statistics and measurement issues as applied to organization development (OD) including reliability and a sampling of inferential statistics. Topics include keeping in mind the characteristics such as relevance or acceptability, need of quantitative measurement in organizational intervention, and internal consistency estimate.

Purpose: Genetic variants identified through population-based genome-wide studies are generally of high frequency, exerting their action in the central part of the refractive error spectrum. However, the power to identify associations with variants of lower minor allele frequency is greatly reduced, requiring considerable sample sizes. Here we aim to assess the impact of rare variants on genetic variation of refractive errors in a very large general population cohort. Methods: Genetic association analyses of non-cyclopaedic autorefraction calculated as mean spherical equivalent (SPHE) used whole-exome sequence genotypic information from 50,893 unrelated participants in the UK Biobank of European ancestry. Gene-based analyses tested for association with SPHE using an optimised SNP-set kernel association test (SKAT-O) restricted to rare variants (minor allele frequency < 1%) within protein-coding regions of the genome. All models were adjusted for age, sex and common lead variants within the same locus reported by previous genome-wide association studies. Potentially causal markers driving association at significant loci were elucidated using sensitivity analyses by sequentially dropping the most associated variants from gene-based analyses. Results: We found strong statistical evidence for association of SPHE with the SIX6 (p-value = 2.15 x 10−10, or Bonferroni-Corrected p = 4.41x10-06) and the CRX gene (p-value = 6.65 x 10−08, or Bonferroni-Corrected p = 0.001). The SIX6 gene codes for a transcription factor believed to be critical to the eye, retina and optic disc development and morphology, while CRX regulates photoreceptor specification and expression of over 700 genes in the retina. These novel associations suggest an important role of genes involved in eye morphogenesis in refractive error. Conclusion: The results of our study support previous research highlighting the importance of rare variants to the genetic risk of refractive error. We explain some of the origins of the genetic signals seen in GWAS but also report for the first time a completely novel association with the CRX gene. [ABSTRACT FROM AUTHOR]

Background: To investigate the relationship between dietary intake of niacin (water‐soluble form of vitamin B3) and retinal nerve fibre layer (RNFL) thickness in healthy eyes. Methods: This cross‐sectional study examined the association between daily niacin intake and RNFL thickness in three large population‐based cohorts with varied age differences. RNFL thickness was extracted from optical coherence tomography data; energy‐adjusted niacin intake was estimated from food frequency questionnaires. Linear mixed‐effects models were utilised to examine the association between RNFL thickness and energy‐adjusted niacin intake. Three separate analyses were conducted, with niacin treated as a continuous, a categorical (quartiles) or a dichotomous (above/below Australian recommended daily intake) variable. Results: In total, 4937 subjects were included in the study [Raine Study Gen2, n = 1204, median age 20; Busselton Healthy Ageing Study (BHAS), n = 1791, median age 64; TwinsUK, n = 1942, median age 64). When analysed as a continuous variable, there was no association between RNFL thickness and niacin intake in any of the three cohorts (95% CI β: Raine Study Gen 2, −0.174 to 0.074; BHAS, −0.066 to 0.078; TwinsUK −0.435 to 0.350). Similar findings were observed with quartiles of niacin intake and for niacin intakes above or below Australian recommended daily intake levels in all three cohorts. Conclusions: Dietary intake of niacin from a standard diet does not appear to be associated with age‐related RNFL thinning in healthy eyes. Supraphysiological doses of niacin may be required for therapeutic effect in the retina. [ABSTRACT FROM AUTHOR]

Abstract: Heritability is the proportion of phenotypic variation in a population that is attributable to genetic variation among individuals. Many ophthalmic disorders and biometric traits are known to have a genetic basis and consequently much work has been published in the literature estimating the heritability of various ocular parameters. We collated and summarized the findings of heritability studies conducted in the field of ophthalmology. We grouped the various studies broadly by phenotype as follows: refraction, primary open-angle glaucoma, age-related macular degeneration (AMD), cataract, diabetic retinopathy, and others. A total of 82 articles were retrieved from the literature relating to estimation of heritability for an ocular disease or biometric trait; of these, 37 papers were concerned with glaucoma, 28 with refraction, 4 with AMD, 5 with diabetic retinopathy, and 4 with cataract. The highest reported heritability for an ophthalmic trait is 0.99 for the phenotype ≥ 20 small hard drusen, indicating that observed variation in this parameter is largely governed by genetic factors. Over 60% of the studies employed a twin study design and a similar percentage utilized variance components methods and structural equation modeling (SEM) to derive their heritability values. Using modern SEM techniques, heritability estimates derived from twin subjects were generally higher than those from family data. Many of the estimates are in the moderate to high range, but to date the majority of genetic variants accounting for these findings have not been uncovered, hence much work remains to be undertaken to elucidate fully their molecular etiology. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Limited evidence suggests that focal neurological injury (e.g., acute flaccid paralysis) caused by infection with the West Nile virus (WNV) is more common in older patients. We re-evaluate this association in a series of patients who were infected with the WNV during the 2002 epidemic. Methods: We performed a retrospective chart review of 34 patients who were hospitalized for treatment of serologically confirmed WNV infection. Measurements included the patient''s demographic characteristics, baseline medical diagnoses, the occurrence of symptoms and exam findings, the results of various diagnostic tests, and the patient''s clinical outcome. Results: Patients infected with the WNV who developed focal neurological injury were found to be comparable to patients who did not develop focal neurological injury both in terms of patient age and the number of medical conditions the patient had prior to infection. This is in contrast to WNV-infected patients who developed an encephalitis-like clinical course, or who died or were institutionalized after their hospitalization; such patients tended to be older and–in cases with a poor outcome–have more medical conditions prior to WNV infection. Conclusions: In our patient group, focal neurological injury caused by WNV infection was not related to advanced patient age or to the number of medical conditions the patient had prior to infection. Our findings bring into question commonly held views about the development of focal neurological injury caused by WNV infection, and they raise concerns about the management of future WNV epidemics and the testing and use of potential antiviral treatments against this infection. [Copyright &y& Elsevier]

Preliminary findings are reported following the detailed analysis of intramolecular vibrational energy redistribution (IVR) in S1 para-fluorotoluene following the excitation of one quantum in the CF stretching mode ?7. It is shown that the method proposed has the potential to enable not only the determination of a rate constant for IVR, but also the identification of the dark states into which energy has redistributed. In addition energy flow has been observed from a bright state (11 1 ) previously thought to be below the onset for IVR in this molecule, and evidence of mode-specificity in the IVR process. [ABSTRACT FROM AUTHOR]

SIX1/SIX6 polymorphism has been shown to be associated with glaucoma. Studies have also found that, in older adults, retinal nerve fibre layer (RNFL) thickness is significantly thinned with each copy of the risk allele in SIX1/SIX6. However, it is not known whether these genetic variants exert their effects in younger individuals. Comparing a healthy young adult with an older adult cohort (mean age 20 vs 63 years), both of Northern European descent, we found that there was no significant RNFL thinning in each copy of the risk alleles in SIX1/SIX6 in the eyes of younger individuals. The older cohort showed an unexpectedly thicker RNFL in the nasal sector with each copy of the risk allele for both the SIX1 (rs10483727) and SIX6 (rs33912345) variants. In the temporal sector, thinner RNFL was found with each copy of the risk allele in rs33912345 with a decrease trend observed in rs10483727. Our results suggest that SIX1/SIX6 gene variants exert their influence later in adult life. [ABSTRACT FROM AUTHOR]

To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell–inner plexiform layer (GCIPL) thicknesses in a large cohort. Cross-sectional study. We included 42 044 participants in the UK Biobank. The mean age was 56 years. Spectral-domain OCT macular images were segmented and analyzed. Corneal-compensated intraocular pressure (IOPcc) was measured with the Ocular Response Analyzer (Reichert, Corp., Buffalo, NY). Multivariable linear regression was used to examine associations with mean mRNFL, GCC, and GCIPL thicknesses. Factors examined were age, sex, ethnicity, height, body mass index (BMI), smoking status, alcohol intake, Townsend deprivation index, education level, diabetes status, spherical equivalent, and IOPcc. Thicknesses of mRNFL, GCC, and GCIPL. We identified several novel independent associations with thinner inner retinal thickness. Thinner inner retina was associated with alcohol intake (most significant for GCIPL: –0.46 μm for daily or almost daily intake compared with special occasion only or never [95% confidence interval (CI), 0.61–0.30]; P = 1.1×10–8), greater social deprivation (most significant for GCIPL: –0.28 μm for most deprived quartile compared with least deprived quartile [95% CI, –0.42 to –0.14]; P = 6.6×10–5), lower educational attainment (most significant for mRNFL: –0.36 μm for less than O level compared with degree level [95% CI, –0.45 to 0.26]; P = 2.3×10–14), and nonwhite ethnicity (most significant for mRNFL comparing blacks with whites: –1.65 μm [95% CI, –1.86 to –1.43]; P = 2.4×10–50). Corneal-compensated intraocular pressure was associated most significantly with GCIPL (–0.04 μm/mmHg [95% CI, –0.05 to –0.03]; P = 4.0×10–10) and was not associated significantly with mRNFL (0.00 μm/mmHg [95% CI, –0.01 to 0.01]; P = 0.77). The variables examined explained a greater proportion of the variance of GCIPL (11%) than GCC (6%) or mRNFL (7%). The novel associations we identified may be important to consider when using inner retinal parameters as a diagnostic tool. Associations generally were strongest with GCIPL, particularly for IOP. This suggests that GCIPL may be the superior inner retinal biomarker for macular pathophysiologic processes and especially for glaucoma. [ABSTRACT FROM AUTHOR]

Aims/Purpose: Glaucoma is an eye disease that is the commonest cause of irreversible blindness worldwide. It has been suggested that gut microbiota can produce reactive oxygen species and pro‐inflammatory cytokines that may travel from the gastric mucosa to distal sites, such as the optic nerve head or trabecular meshwork. There is evidence for a gut‐eye axis, as microbial dysbiosis has been associated with retinal diseases. Here, we investigated the association between glaucoma prevalence and the gut microbiome. Moreover, we analysed the association of the gut microbiome with intraocular pressure (IOP; risk factor of glaucoma) and vertical cup‐to‐disc ratio (VCDR; quantifying glaucoma severity). Methods: The discovery analyses included participants of the Rotterdam Study and the Erasmus Glaucoma Cohort. A total of 225 glaucoma patients were matched on age and sex with 1247 participants without glaucoma. Stool samples were collected and used to generate 16S rRNA gene profiles. We assessed associations with 233 taxa. We used data from the TwinsUK and the Study of Health in Pomerania (SHIP) to replicate our findings. The TwinsUK dataset consisted of 32 participants with glaucoma and 1542 unrelated, unmatched participants without glaucoma. The SHIP dataset consisted of a total of 2546 participants. Results: Several butyrate‐producing taxa (e.g., Butyrivibrio, Caproiciproducens, Clostridium sensu stricto 1, Coprococcus 1, Ruminococcaceae UCG 007, Shuttleworthia) were associated with lower glaucoma prevalence, lower IOP, and smaller VCDR. The replication analyses confirmed the findings from the discovery analyses. Conclusions: Large human studies exploring the link between the gut microbiome and glaucoma are lacking. Our results support the hypothesis that microbial dysbiosis plays a role in the pathophysiology of glaucoma. This research may support future research into the mediating role of butyrate‐producing taxa in the relation between dietary intake and glaucoma. [ABSTRACT FROM AUTHOR]

This study investigates a range of commercially available γ-Al2O3 powders by using a combination of integrated experimental techniques. These included general measurements of powder properties by using helium density, BET surface area, and scanning electron microscopy (SEM) analyses. In addition, dynamic light scattering and zeta potential measurements were used to investigate nanoparticle dispersions. Bulk crystal structures were analysed by using comparative X-ray and neutron powder diffraction (XRD and NPD) analyses. Conventional transmission electron microscopy (TEM) was used to determine particle morphology, particle size, composition, and structure. Aberration-corrected TEM was used to investigate the crystallinity of nanoparticles including the existence of any surface reconstruction on commonly observed facetted, cubeoctahedral γ -Al2O3 nanoparticles. From the observation of peak splittings in diffraction data, we favour a description of the γ-Al2O3 structure based on a distortion of the conventionally accepted face-centred cubic ( Fd $\bar 3$ m) structure into a tetragonal I41/ amd structure. Distinct differences between TEM, XRD, and NPD data indicate the presence of some cation disorder within a rigid close-packed oxygen framework. The Rietveld refinement of the NPD data suggests a high level of microstrain of 1.2 %. An improvement to the model is achieved by reducing the aluminium content in the unit cell, which is commensurate with the migration of aluminium ions to the surface and some degree of nonstoichiometry in the particle core. Aberration-corrected TEM imaging and exit wave reconstruction confirm previous evidence for the presence of enhanced surface contrast at {1 1 1} surface facets, which we associate with the presence of excess cation termination. In addition, these {1 1 1} facets are observed to be heavily stepped. These results may have important implications for the thermal stability of metal catalyst nanoparticles on these high-surface area supports; the migration of aluminium ions to the surface provides clear evidence of why these materials perform so well as catalyst supports. [ABSTRACT FROM AUTHOR]

High melanocytic nevus count is a strong predictor of melanoma risk. A GWAS of nevus count in Australian adolescent twins identified an association of nevus count with the interferon regulatory factor 4 gene (IRF4 [p = 6 × 10−9]). There was a strong genotype-by-age interaction, which was replicated in independent UK samples of adolescents and adults. The rs12203592∗T allele was associated with high nevus counts and high freckling scores in adolescents, but with low nevus counts and high freckling scores in adults. The rs12203592∗T increased counts of flat (compound and junctional) nevi in Australian adolescent twins, but decreased counts of raised (intradermal) nevi. In combined analysis of melanoma case-control data from Australia, the UK, and Sweden, the rs12203592∗C allele was associated with melanoma (odds ratio [OR] 1.15, p = 4 × 10−3), most significantly on the trunk (OR = 1.33, p = 2.5 × 10−5). The melanoma association was corroborated in a GWAS performed by the GenoMEL consortium for an adjacent SNP, rs872071 (rs872071∗T: OR 1.14, p = 0.0035; excluding Australian, the UK, and Swedish samples typed at rs12203592: OR 1.08, p = 0.08). [ABSTRACT FROM AUTHOR]

Purpose: To examine the roles of genetic and environmental factors in corneal hysteresis and ocular pulse amplitude by performing a classic twin study. Design: Cross-sectional twin study. Participants and/or Controls: Two hundred sixty-four twin pairs: 135 monozygotic (MZ) and 129 dizygotic (DZ). Methods: Corneal hysteresis was measured using the Reichert Ocular Response Analyzer (ORA; Reichert, Buffalo, NY), and ocular pulse amplitude was measured using the Pascal Dynamic Contour Tonometer (DCT; Swiss Microtechnology AG, Port, Switzerland). Main Outcome Measures: Contribution of genetic and environmental effects on corneal hysteresis and OPA among MZ and DZ twins. Results: The mean corneal hysteresis was10.24±1.54 mmHg and the mean ocular pulse amplitude was 2.88±0.97 mmHg. The MZ correlations were higher than DZ for both corneal hysteresis and ocular pulse amplitude (correlation coefficients, 0.75:0.42 and 0.59:0.32 for MZ:DZ twins, respectively). Modeling suggested heritability of corneal hysteresis of 0.77 (95% confidence interval [CI], 0.70–0.82), with the remaining proportion of variance because of individual environmental effects of 0.23 (95% CI, 0.18–0.30). For ocular pulse amplitude, the heritability was 0.62 (95% CI, 0.51–0.70), with the remaining proportion of variance the result of individual environmental effects of 0.38 (95% CI, 0.30–0.49). Conclusions: This study demonstrated that additive genetic influences explained most of the individual differences in corneal hysteresis and ocular pulse amplitude among these twins. Financial Disclosure(s): The authors have no proprietary or commercial interest in any materials discussed in this article. [Copyright &y& Elsevier]

Objectives.—To determine the relationship between levels of ouabain-like compounds (OLC) in the cerebrospinal fluid (CSF) and the occurence of idiopathic intracranial hypertension (IIH). Background.—OLC are naturally occurring inhibitors of the sodium-potassium ATPase that are found in the CSF of mammals. Since the production of CSF is dependent upon sodium-potassium ATPase activity, and since there is evidence that the increased intracranial pressure found in the condition of IIH may be the result of increased CSF production, we hypothesized that the level of endogenous OLC would be reduced in the CSF of patients with IIH. Methods.—CSF samples were obtained from n = 7 patients with IIH and n = 31 patients with neurological disorders other than IIH (“control” patients) who had lumbar puncture as part of their routine evaluation or treatment. The concentration of OLC in the CSF samples was measured using an established ELISA. Results.—Patients with IIH exhibited a concentration of OLC in the CSF of 0.11 ± 0.03 ng/mL. In comparison, the concentration of OLC in CSF samples from non-IIH control patients was 0.12 ± 0.01 ng/mL. These values were not statistically different when compared with a t-test ( P= 0.31). However, the concentration of OLC did negatively correlate to the opening pressure on lumbar puncture, but only in the IIH group ( r=−0.80, P= .03). Furthermore, IIH patients who were newly diagnosed or who were unsuccessfully treated (n = 5 of 7 IIH patients) exhibited OLC concentrations of 0.06 ± 0.1 ng/mL, which is nearly lower than that of the control group ( P= .06). Conclusions.—The average concentration of OLC in IIH patients (treated and untreated) is unlikely to be distinguishable from that in non-IIH control patients with other neurological conditions. However, the concentration of OLC may be inversely related to the intracranial pressure in patients with IIH, and it may prove to be lower in the subgroup of untreated and unsuccessfully treated IIH patients. [ABSTRACT FROM AUTHOR]