Biometric gonioscopy and the effects of age, race, and sex on the anterior chamber angle.

AIM:

To utilise a novel method for making measurements in the anterior chamber in order to compare the anterior chamber angles of people of European, African, and east Asian descent aged 40 years and over.

METHODS:

A cross sectional study on 15 people of each sex from each decade from the 40s to the 70s, from each of three racial groups-black, white, and Chinese Singaporeans. Biometric gonioscopy (BG) utilises a slit lamp mounted reticule to make measurements from the apparent iris insertion to Schwalbe's line through a Goldmann one mirror goniolens. The main outcome measures were BG measurements of the anterior chamber angle as detailed above.

RESULTS:

There was no significant difference in angle measurement between black, white, and Chinese races in this study. However, at younger ages people of Chinese race appeared to have deeper angles than white or black people, whereas the angles of older Chinese were significantly narrower (p = 0.004 for the difference in slope of BG by age between Chinese and both black and white people).

CONCLUSION:

The failure to detect a difference in angle measurements between these groups was surprising, given the much higher prevalence of angle closure among Chinese. It appears that the overall apparent similarity of BG means between Chinese and Western populations may mask very different trends with age. The apparently more rapid decline in angle width measurements with age among Chinese may be due to the higher prevalence of cataract or "creeping angle closure." However, longitudinal inferences from cross sectional data are problematic, and this may represent a cohort phenomenon caused by the increasing prevalence of myopia in the younger Singaporean population.

Age, gender, biometry, refractive error, and the anterior chamber angle among Alaskan Eskimos.

BACKGROUND:

The prevalence of angle-closure glaucoma (ACG) is greater for Eskimos/Inuit than it is for any other ethnic group in the world. Although it has been suggested that this prevalence may be due to a population tendency toward shallower anterior chamber angles, available evidence for other populations such as Chinese with high rates of ACG has not consistently demonstrated such a tendency.

METHODS:

A reticule, slit-lamp, and standard Goldmann one-mirror goniolens were used to make measurements in the anterior chamber (AC) angle according to a previously reported protocol for biometric gonioscopy (BG) (Ophthalmology 1999;106:2161-7). Measurements were made in all four quadrants of one eye among 133 phakic Alaskan Eskimos aged 40 years and older. Automatic refraction, dilated examination of the anterior segment and optic nerve, and A-scan measurements of AC depth, lens thickness, and axial length were also carried out for all subjects.

RESULTS:

Both central and peripheral AC measurements for the Eskimo subjects were significantly lower than those previously reported by us for Chinese, blacks, and whites under the identical protocol. Eskimos also seemed to have somewhat more hyperopia. There were no differences in biometric measurements between men and women in this Eskimo population. Angle measurements by BG seemed to decline more rapidly over life among Eskimos and Chinese than blacks or whites. Although there was a significant apparent decrease in AC depth, increase in lens thickness, and increase in hyperopia with age among Eskimos, all of these trends seemed to reverse in the seventh decade and beyond.

CONCLUSIONS:

Eskimos do seem to have shallower ACs than do other racial groups. Measurements of the AC angle seem to decline more rapidly over life among Eskimos than among blacks or whites, a phenomenon also observed by us among Chinese, another group with high ACG prevalence. This apparent more rapid decline may be due to a cohort effect with higher prevalence of myopia and resulting wider angles among younger Eskimos and Chinese.

A method of measuring anterior chamber volume using the anterior segment optical coherence tomographer and specialized software.

PURPOSE: To describe and evaluate a new method for measuring anterior chamber volume (ACV). DESIGN: Observational case series. METHODS: The authors measured ACV using the anterior chamber (AC) optical coherence tomographer (OCT) and applied image-processing software developed by them. Repeatability was evaluated. The ACV was measured in patient groups with normal ACs, shallow ACs, and deep ACs. The volume difference before and after laser peripheral iridotomy (LPI) was analyzed for the shallow and deep groups. RESULTS: Coefficients of repeatability for intraoperator, interoperator, and interimage measurements were 0.406%, 0.958%, and 0.851%, respectively. The limits of agreement for intraoperator and interoperator measurement were -0.911 microl to 1.343 microl and -7.875 microl to -2.463 microl, respectively. There were significant ACV differences in normal, shallow, and deep AC eyes (P < .001) and before and after LPI in shallow AC (P < .001) and deep AC (P = .008) eyes. CONCLUSIONS: The ACV values obtained by this method were repeatable and in accord with clinical observation.

Characterisation of a two-dimensional liquid-filled ion chamber detector array using flattened and unflattened beams for small fields, small MUs and high dose-rates

In this study, the PTW 1000SRS array with Octavius 4D phantom was characterised for FF and FFF beams. MU linearity, field size, dose rate, dose per pulse (DPP) response and dynamic conformal arc treatment accuracy of the 1000SRS array were assessed for 6MV, 6FFF and 10FFF beams using a Varian TrueBeam STx linac. The measurements were compared with a pinpoint IC, microdiamond IC and EBT3 Gafchromic film. Measured dose profiles and FWHMs were compared with film measurements. Verification of FFF volumetric modulated arc therapy (VMAT) clinical plans were assessed using gamma analysis with 3%/3 mm and 2%/2 mm tolerances (10% threshold). To assess the effect of cross calibration dose rate, clinical plans with different dose rates were delivered and analysed. Output factors agreed with film measurements to within 4.5% for fields between 0.5 and 1 cm and within 2.7% for field sizes between 1.5 and 10 cm and were highly correlated with the microdiamond IC detector. Field sizes measured with the 1000SRS array were within 0.5 mm of film measurements. A drop in response of up to 1.8%, 2.4% and 5.2% for 6MV, 6FFF and 10FFF beams respectively was observed with increasing nominal dose rate. With an increase in DPP, a drop of up to 1.7%, 2.4% and 4.2% was observed in 6MV, 6FFF and 10FFF respectively. The differences in dose following dynamic conformal arc deliveries were less than 1% (all energies) from calculated. Delivered VMAT plans showed an average pass percentage of 99.5(±0.8)% and 98.4(±3.4)% with 2%/2 mm criteria for 6FFF and 10FFF respectively. A drop to 97.7(±2.2)% and 88.4(±9.6)% were observed for 6FFF and 10FFF respectively when plans were delivered at the minimum dose rate and calibrated at the maximum dose rate. Calibration using a beam with the average dose rate of the plan may be an efficient method to overcome the dose rate effects observed by the 1000SRS array.

Pacific Northwest Chamber Music Festival, June 28, 30 and July 5, 9, 1988

Concert program for Pacific Northwest Chamber Music Festival, June 28, 30 and July 5, 9, 1988

Chamber Music Recital, May 1, 1960

Concert Program for Chamber Music Recital, May 1st, 1960

Rare Gems: Uncommon Chamber Music January 18, 2001

Concert Program for Rare Gems: Uncommon Chamber Music January 18, 2001

Differential effect of long versus short wavelength light exposure on pupillary re-dilation in patients with outer retinal disease.

BACKGROUND: In patients with outer retinal degeneration, a differential pupil response to long wavelength (red) versus short wavelength (blue) light stimulation has been previously observed. The goal of this study was to quantify differences in the pupillary re-dilation following exposure to red versus blue light in patients with outer retinal disease and compare them with patients with optic neuropathy and with healthy subjects. DESIGN: Prospective comparative cohort study. PARTICIPANTS: Twenty-three patients with outer retinal disease, 13 patients with optic neuropathy and 14 normal subjects. METHODS: Subjects were tested using continuous red and blue light stimulation at three intensities (1, 10 and 100 cd/m2) for 13 s per intensity. Pupillary re-dilation dynamics following the brightest intensity was analysed and compared between the three groups. MAIN OUTCOME MEASURES: The parameters of pupil re-dilation used in this study were: time to recover 90% of baseline size; mean pupil size at early and late phases of re-dilation; and differential re-dilation time for blue versus red light. RESULTS: Patients with outer retinal disease showed a pupil that tended to stay smaller after light termination and thus had a longer time to recovery. The differential re-dilation time was significantly greater in patients with outer retinal disease (median = 28.0 s, P < 0.0001) compared with controls and patients with optic neuropathy. CONCLUSIONS: A differential response of pupil re-dilation following red versus blue light stimulation is present in patients with outer retinal disease but is not found in normal eyes or among patients with visual loss from optic neuropathy.

Senate Chamber

Senate Chambers in A Block of the MacKenzie Chown Complex.

Does altering brachial artery tone with lower-body negative pressure and flow-mediated dilation affect arterial stiffness?

Although medium sized, muscular vessels normally respond to sympathetic stimulation by reducing compliance, it is unclear whether the large brachial artery is similarly affected by sympathetic stimulation induced via lower-body negative pressure (LBNP). Similarly, the impact of flow-mediated dilation (FMD) on brachial artery compliance and distensibility remains unresolved, hi addition, before such measures can be used as prognostic tools, it is important to investigate the reliability and repeatability of both techniques. Using a randomized order design, the effects of LBNP and FMD on the mechanical properties of the brachial artery were examined in nine healthy male subjects (mean age 24y). Non-invasive Doppler ultrasound and a Finometer were used to measure simultaneously the variation in systolic and diastolic diameter, and brachial blood pressure, respectively. These values were used to calculate compliance and distensibility values at baseline, and during both LBNP and FMD. The within-day and between-day repeatability of arterial diameter, compliance, distensibility, and FMD measures were assessed using the error coefficient and intra-class correlation coefficient (ICC). While heart rate (P<0.01) and peripheral resistance increased during LBNP (P<0.05), forearm blood flow and pulse pressure decreased (P<0.01). hi terms of mechanical properties, vessel diameters decreased (P<0.05), but both compliance and distensibility were not changed. On the other hand, FMD resulted in a significant increase in diameter (P<0.001), with no change in compliance or distensibility. hi summary, LBNP and FMD do not appear to alter brachial artery compliance or distensibility in young, healthy males. Whereas measures ofFMD were not found to be repeatable between days, the ICC indicated that compliance and distensibility were repeatable only within-day.

Chamber's Historical Questions with Answers

The book is hardcover and inscribed with an illegible signature, dated 1880 and below that is the signature Margaret J. Woodruff. The preface of the book begins, "The present work is designed to fulfil an important purpose in Education - that of bringing clearly into view the leading facts which are supposed to be gained through a long course of instruction. Without proposing to supersede the elementary books usually employed, it offers a certain test of what is presumed to have been previously learned. With such a work in their hands, Schoolmasters, Tutors, Governesses, or Parents, may at once satisfy themselves as to the degree of knowledge on a variety of subjects attained by the young person under their charge, and for whose intellectual culture they feel a special interest." The full text is available in the Brock University Special Collections and Archives.

St. Catharines and District Chamber of Commerce records, 1943-1992, n.d.

The St. Catharines and District Chamber of Commerce merged with the Thorold Chamber of Commerce in 2006. In 2012, they joined a region wide Chamber, becoming part of the Greater Niagara Chamber of Commerce. The Chamber is a "is a non-partisan, non-sectarian association of businesses, groups and individuals who support business growth and effective government fostering a sustainable and vibrant Niagara."

Engineer estimate (5 ½ pages, handwritten) in the marsh lands drainage presented to the Chamber and Councilors of the County of Welland in council assembled

Engineer estimate (5 ½ pages, handwritten) in the marsh lands drainage presented to the Chamber and Councilors of the County of Welland in council assembled. This report is signed by S.D. Woodruff, June 20, 1857.

Role of nucleotides on lung epithelial cells : mechanism of release and development of a side-view microscopic chamber to study nucleotide-dependent airway surface liquid height

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

Réduction d'expansion volumique au cours de la gestation : conséquence sur la circulation utéro-placentaire.

La grossesse est caractérisée par une augmentation du volume circulant maternel et du débit sanguin afin de subvenir aux besoins croissants du foetus. En diminuant l'expansion volumique maternelle, nous avons développé un modèle de restriction de croissance intra-utérine (RCIU) chez la rate dans lequel on observe une diminution du diamètre des artères utérines arquées ainsi qu'une diminution de la réponse à l'angiotensine II. Nous avons émis l'hypothèse que comparativement aux rates normales, les vaisseaux utérins des rates RCIU présentent une dysfonction des mécanismes de relaxation dépendant de l'endothélium lors de la réponse à des agents vasoactifs. Notre objectif était de caractériser l'influence de l'endothélium sur la régulation de la réactivité des artères utérines radiales dans notre modèle RCIU. À l'aide d'un myographe pressurisé, des courbes de concentration-réponse à des agents vasoactifs (Phényléphrine (Pe), Carbachol (Cbc) et Nitroprussiate de sodium (SNP)) ont été effectuées, en présence ou en absence d'inhibiteurs des voies principales de la relaxation dépendante de l'endothélium (monoxyde d'azote (NO), prostacycline (PGI2) et facteurs hyperpolarisants dépendant de l'endothélium (EDHF)). Nous avons ainsi démontré que les artères utérines radiales des rates RCIU ont un diamètre plus petit que celles des rates contrôles. Une utilisation plus grande du NO dans la réponse dilatatrice au Cbc a été observée chez les rates RCIU. De plus, l'inhibition de la voie de l'EDHF par l'ajout de KCl aux inhibiteurs de la voie du NO (L-NAME) et des PGI2 (Ibuprofène) bloque presque complètement la relaxation au Cbc chez les deux groupes. En conclusion, dans les artères utérines radiales des deux groupes, il y a une participation importante de l'EDHF lors de la dilatation au Cbc. De plus, dans notre modèle RCIU, la voie du NO est activée, probablement afin de compenser la diminution du diamètre des artères et la réduction de la perfusion utérine.