Repeatability and reproducibility of the galilei G6 and its agreement with the pentacam® AXL in optical biometry and corneal tomography.

Objectives: To assess the repeatability and reproducibility of corneal measurements performed by the Galilei G6 and determine its agreement with the Pentacam® AXL.

Methods: 105 eyes underwent examination by both devices, measuring nine parameters. Paired t-tests, Deming Regression, and Bland-Altman plots were used to determine agreement.

[Hypothermia during Treatment with Aripiprazole].

Disturbances of thermoregulation are a well-known side effect of neuroleptic treatment, especially hyperthermia. Hypothermia can occur also during treatment with neuroleptics. Now hypothermia is more and more due to atypical neuroleptics in relation to 5-HT antagonism.

Submicron-Scale Heterogeneities in Nickel Sorption of Various Cell-Mineral Aggregates Formed by Fe(II)-Oxidizing Bacteria.

Fe(II)-oxidizing bacteria form biogenic cell-mineral aggregates (CMAs) composed of microbial cells, extracellular organic compounds, and ferric iron minerals. CMAs are capable of immobilizing large quantities of heavy metals, such as nickel, via sorption processes. CMAs play an important role for the fate of heavy metals in the environment, particularly in systems characterized by elevated concentrations of dissolved metals, such as mine drainage or contaminated sediments.

Experimental diagenesis of organo-mineral structures formed by microaerophilic Fe(II)-oxidizing bacteria.

Twisted stalks are organo-mineral structures produced by some microaerophilic Fe(II)-oxidizing bacteria at O2 concentrations as low as 3 μM. The presence of these structures in rocks having experienced a diagenetic history could indicate microbial Fe(II)-oxidizing activity as well as localized abundance of oxygen at the time of sediment deposition. Here we use spectroscopy and analytical microscopy to evaluate if--and what kind of--transformations occur in twisted stalks through experimental diagenesis.

Visually-driven ocular growth in mice requires functional rod photoreceptors.

Purpose: Proper refractive eye growth depends on several features of the visual image and requisite retinal pathways. In this study, we determined the contribution of rod pathways to normal refractive development and form deprivation (FD) myopia by testing Gnat1(-/-) mice, which lack functional rods due to a mutation in rod transducin-α.

Methods: Refractive development was measured in Gnat1(-/-) (n = 30-36) and wild-type (WT) mice (n = 5-9) from 4 to 12 weeks of age.

Synchrotron-based chemical nano-tomography of microbial cell-mineral aggregates in their natural, hydrated state.

Chemical nano-tomography of microbial cells in their natural, hydrated state provides direct evidence of metabolic and chemical processes. Cells of the nitrate-reducing Acidovorax sp. strain BoFeN1 were cultured in the presence of ferrous iron.

3D chemical mapping: application of scanning transmission (soft) X-ray microscopy (STXM) in combination with angle-scan tomography in bio-, geo-, and environmental sciences.

The identification of environmental processes and mechanisms often requires information on the organochemical and inorganic composition of specimens at high spatial resolution. X-ray spectroscopy (XAS) performed in the soft X-ray range (100-2,200 eV) provides chemical speciation information for elements that are of high biogeochemical relevance such as carbon, nitrogen, and oxygen but also includes transition metals such as iron, manganese, or nickel. Synchrotron-based scanning transmission X-ray microscopy (STXM) combines XAS with high resolution mapping on the 20-nm scale.

Retinal degeneration increases susceptibility to myopia in mice.

Purpose: Retinal diseases are often associated with refractive errors, suggesting the importance of normal retinal signaling during emmetropization. For instance, retinitis pigmentosa, a disease characterized by severe photoreceptor degeneration, is associated with myopia; however, the underlying link between these conditions is not known. This study examines the influence of photoreceptor degeneration on refractive development by testing two mouse models of retinitis pigmentosa under normal and form deprivation visual conditions.

Assessment of axial length measurements in mouse eyes.

Purpose: To compare measurements of murine ocular axial lengths (ALs) made with 780 nm partial coherence interferometry (PCI) and 1310 nm spectral domain-optical coherence tomography (SD-OCT).

Methods: AL was measured at postnatal day (P) 58 in C57BL/6J mice. Repeated AL measurements were taken using a custom-made 780 nm PCI and a commercial 1310 nm SD-OCT.

Exaggerated eye growth in IRBP-deficient mice in early development.

Purpose: Because interphotoreceptor retinoid-binding protein (IRBP) is expressed before being needed in its presumptive role in the visual cycle, we tested whether it controls eye growth during development.

Methods: The eyes of congenic IRBP knockout (KO) and C57BL/6J wild-type (WT) mice ranging in age from postnatal day (P)2 to P440 were compared by histology, laser micrometry, cycloplegic photorefractions, and partial coherence interferometry.

Results: The size and weight of IRBP KO mouse eyes were greater than those of the WT mouse, even before eye-opening.

Association between retinal steepness and central myopic shift in children.

Purpose: Retinal steepness at the posterior pole was shown to be associated with peripheral refraction, and there exists strong evidence that peripheral refraction influences central refractive development. The purpose of this study was to investigate whether retinal steepness is associated with central myopic shift in children.

Methods: Central refraction was measured in OD of 140 children aged 7 to 11 years as central sphere equivalent refraction (CSER) and central sphere refraction at baseline and after ~30 months.

In vivo human choroidal thickness measurements: evidence for diurnal fluctuations.

Purpose: The authors applied partial coherence interferometry (PCI) to estimate the thickness of the human choroid in vivo and to learn whether it fluctuates during the day.

Methods: By applying signal processing techniques to existing PCI tracings of human ocular axial length measurements, a signal modeling algorithm was developed and validated to determine the position and variability of a postretinal peak that, by analogy to animal studies, likely corresponds to the choroidal/scleral interface. The algorithm then was applied to diurnal axial eye length datasets.

The relation of axial length and intraocular pressure fluctuations in human eyes.

Purpose: To determine in human eyes whether diurnal fluctuations in axial length are related to fluctuations in intraocular pressure (IOP) by studying these fluctuations in both eyes of individual subjects and by assessing the regularity of both rhythms on two separate study days.

Methods: Ten subjects, ages 18 to 24 years, underwent serial axial length and IOP measurements using highly precise, noncontact partial coherence interferometry and Goldmann applanation tonometry, respectively. Both eyes were measured at six 3-hour intervals during each of two study days, and significant fluctuations were modeled by sine curves.

Emmetropisation under continuous but non-constant light in chicks.

It has been suggested that ambient lighting at night influences eye growth and might play a causal role in human myopia. To test this hypothesis, we reared newly hatched chicks under 12 hr light-dark or light-dim cycles with a light phase intensity of 1500 microW/cm(2) and variable dim phase intensities between 0.01 and 500 microW/cm(2).

Diurnal axial length fluctuations in human eyes.

Purpose: This study sought diurnal variations of eye length in human subjects, analogous to those reported in laboratory animals.

Methods: Seventeen subjects, ages 7 to 53 (median 16) years and mean spherical equivalent refractive error -0.68 D (range, -3.

Axial and peripheral eye length measured with optical low coherence reflectometry.

An optical low-coherence reflectometer (OLCR device) is described that allows the precise and noncontact measurement of eye length. The device measures eye length both on-axis and off-axis, thus enabling the determination of eye shape, an ocular parameter thought to be important in the development of refractive error. It is essential for several applications in ophthalmology and vision science.

Variability of retinal steepness at the posterior pole in children 7-15 years of age.

Purpose: Considerable evidence suggests that both axial and peripheral refraction play important roles in eye growth control. The large variability in peripheral refraction seen in adults and children indicates that the peripheral retina is exposed to a wide range of refractive errors. The current lack of appropriate measurement techniques has hampered the determination of whether variability in peripheral refraction between individuals can be correlated with variability in retinal steepness.

Highly precise eye length measurements in children aged 3 through 12 years.

Objective: To determine the feasibility, reliability, and validity of using partial coherence interferometry, a noncontact method that detects interference patterns from various layers of the eye, to measure axial length in young children.

Methods: The right eye of 64 subjects (mean age, 8.4 y; age range, 3.