Comparison of EyeCam and anterior segment optical coherence tomography in detecting angle closure.

PubMed

Baskaran, Mani; Aung, Tin; Friedman, David S; Tun, Tin A; Perera, Shamira A

2012-12-01

To compare the diagnostic performance of EyeCam (Clarity Medical Systems, Pleasanton, CA, USA) and anterior segment optical coherence tomography (ASOCT, Visante; Carl Zeiss Meditec, Dublin, CA, USA) in detecting angle closure, using gonioscopy as the reference standard. Ninety-eight phakic patients, recruited from a glaucoma clinic, underwent gonioscopy by a single examiner, and EyeCam and ASOCT imaging by another examiner. Another observer, masked to gonioscopy findings, graded EyeCam and ASOCT images. For both gonioscopy and EyeCam, a closed angle in a particular quadrant was defined if the posterior trabecular meshwork was not visible. For ASOCT, angle closure was defined by any contact between the iris and angle anterior to the scleral spur. An eye was diagnosed as having angle closure if ≥2 quadrants were closed. Agreement and area under the receiver operating characteristic curves (AUC) were evaluated. The majority of subjects were Chinese (69/98, 70.4%) with a mean age of 60.6 years. Angle closure was diagnosed in 39/98 (39.8%) eyes with gonioscopy, 40/98 (40.8%) with EyeCam and 56/97 (57.7%) with ASOCT. The agreement (kappa statistic) for angle closure diagnosis for gonioscopy versus EyeCam was 0.89; gonioscopy versus ASOCT and EyeCam versus ASOCT were both 0.56. The AUC for detecting eyes with gonioscopic angle closure with EyeCam was 0.978 (95% CI: 0.93-1.0) and 0.847 (95% CI: 0.76-0.92, p < 0.01) for ASOCT. The diagnostic performance of EyeCam was better than ASOCT in detecting angle closure when gonioscopic grading was used as the reference standard. The agreement between the two imaging modalities was moderate. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

Agreement of angle closure assessments between gonioscopy, anterior segment optical coherence tomography and spectral domain optical coherence tomography.

PubMed

Tay, Elton Lik Tong; Yong, Vernon Khet Yau; Lim, Boon Ang; Sia, Stelson; Wong, Elizabeth Poh Ying; Yip, Leonard Wei Leon

2015-01-01

To determine angle closure agreements between gonioscopy and anterior segment optical coherence tomography (AS-OCT), as well as gonioscopy and spectral domain OCT (SD-OCT). A secondary objective was to quantify inter-observer agreements of AS-OCT and SD-OCT assessments. Seventeen consecutive subjects (33 eyes) were recruited from the study hospital's Glaucoma clinic. Gonioscopy was performed by a glaucomatologist masked to OCT results. OCT images were read independently by 2 other glaucomatologists masked to gonioscopy findings as well as each other's analyses of OCT images. Totally 84.8% and 45.5% of scleral spurs were visualized in AS-OCT and SD-OCT images respectively (P<0.01). The agreement for angle closure between AS-OCT and gonioscopy was fair at k=0.31 (95% confidence interval, CI: 0.03-0.59) and k=0.35 (95% CI: 0.07-0.63) for reader 1 and 2 respectively. The agreement for angle closure between SD-OCT and gonioscopy was fair at k=0.21 (95% CI: 0.07-0.49) and slight at k=0.17 (95% CI: 0.08-0.42) for reader 1 and 2 respectively. The inter-reader agreement for angle closure in AS-OCT images was moderate at 0.51 (95% CI: 0.13-0.88). The inter-reader agreement for angle closure in SD-OCT images was slight at 0.18 (95% CI: 0.08-0.45). Significant proportion of scleral spurs were not visualised with SD-OCT imaging resulting in weaker inter-reader agreements. Identifying other angle landmarks in SD-OCT images will allow more consistent angle closure assessments. Gonioscopy and OCT imaging do not always agree in angle closure assessments but have their own advantages, and should be used together and not exclusively.

Relationship between relative lens position and appositional closure in eyes with narrow angles.

PubMed

Otori, Yasumasa; Tomita, Yuki; Hamamoto, Ayumi; Fukui, Kanae; Usui, Shinichi; Tatebayashi, Misako

2011-03-01

To investigate the relationship between relative lens position (RLP) and appositional closure in eyes with narrow angles. Ultrasound biomicroscopy (UBM) was used to measure anterior chamber depth (ACD) and lens thickness (LT), and the IOLMaster to measure axial length (AL). The number of quadrants with appositional closure was assessed by UBM under dark conditions. The RLP was calculated thus: RLP = 10 × (ACD + 0.5 LT) /AL. This study comprised 30 consecutive patients (30 eyes) with narrow-angle eyes defined as Shaffer grade 2 or lower and without peripheral anterior synechiae (24 women, 6 men; mean age ± SD, 67.3 ± 10.4 years; range, 42-87 years). Under dark conditions, 66.7% of the eyes with narrow angles showed appositional closure in at least one quadrant. Of the various ocular biometric parameters, only the RLP significantly decreased with appositional closure in at least one quadrant (P = 0.005). A decrease in the RLP can be predictive of appositional closure for narrow-angle eyes under dark conditions.

Association of iris crypts with acute primary angle closure.

PubMed

Koh, Victor; Chua, Jacqueline; Shi, Yuan; Thakku, Sri Gowtham; Lee, Ryan; Nongpiur, Monisha E; Baskaran, Mani; Kumar, Rajesh S; Perera, Shamira; Aung, Tin; Cheng, Ching-Yu

2017-10-01

To determine the relationship between iris surface features and acute primary angle closure (APAC) in eyes with angle closure. Case-control study involving Asian patients diagnosed with previous APAC, primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG) at an eye centre in Singapore between August 2012 and January 2015. Participants underwent ophthalmic examination and digital slit-lamp iris photography. Iris surface features were graded based on crypts, furrows and colour. Fellow eyes of APAC were compared with PACS and PAC/PACG eyes with regard to their iris surface features. Occurrence of APAC. A total of 309 patients (71 APAC, 139 PACS, 47 PAC and 52 PACG) were included (mean age: 67.7±7.2 years and 36.6% male). Compared with PACS, higher crypt grade was significantly associated with lower odds of APAC (OR=0.58 for one grade higher in crypt grade; p=0.027, adjusted for age, gender, ethnicity and pupil diameter). The results remained similar when compared with PAC/PACG group (OR=0.58 for one grade higher in crypt grade; p=0.043). We did not observe any significant associations between iris furrows or colour with presence of APAC. Our study comprising Asian eyes with angle closure suggests that the presence of a higher crypt grading may be protective for APAC. As such, assessing iris surface architecture for crypts could be a new measure for risk stratification of developing APAC in eyes with angle closure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Demonstration of angle widening using EyeCam after laser peripheral iridotomy in eyes with angle closure.

PubMed

Perera, Shamira A; Quek, Desmond T; Baskaran, Mani; Tun, Tin A; Kumar, Rajesh S; Friedman, David S; Aung, Tin

2010-06-01

To evaluate EyeCam in detecting changes in angle configuration after laser peripheral iridotomy (LPI) in comparison to gonioscopy, the reference standard. Prospective comparative study. Twenty-four subjects (24 eyes) with primary angle-closure glaucoma (PACG) were recruited. Gonioscopy and EyeCam (Clarity Medical Systems) imaging of all 4 angle quadrants were performed, before and 2 weeks after LPI. Images were graded according to angle structures visible by an observer masked to clinical data or the status of LPI, and were performed in a random order. Angle closure in a quadrant was defined as the inability to visualize the posterior trabecular meshwork. We determined the number of quadrants with closed angles and the mean number of clock hours of angle closure before and after LPI in comparison to gonioscopy. Using EyeCam, all 24 eyes showed at least 1 quadrant of angle widening after LPI. The mean number of clock hours of angle closure decreased significantly, from 8.15 +/- 3.47 clock hours before LPI to 1.75 +/- 2.27 clock hours after LPI (P < .0001, Wilcoxon signed rank test). Overall, gonioscopy showed 1.0 +/- 1.41 (95% CI, 0.43-1.57) quadrants opening from closed to open after LPI compared to 2.0 +/- 1.28 (95% CI, 1.49-2.51, P = .009) quadrants with EyeCam. Intra-observer reproducibility of grading the extent of angle closure in clock hours in EyeCam images was moderate to good (intraclass correlation coefficient 0.831). EyeCam may be used to document changes in angle configuration after LPI in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

Angle closure glaucoma in congenital ectropion uvea.

PubMed

Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L

2018-06-01

Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

Fish allergy causing angioedema and secondary angle-closure glaucoma.

PubMed

Calder, Donovan; Calder, Jennifer

2013-03-06

A 56-year-old woman with a history of primary angle-closure glaucoma presented with acute generalised swelling, and facial angioedema following a fish meal. She complained of nausea, vomiting, headache, pain in both eyes and acute loss of vision. Her visual acuity was reduced and intraocular pressures (IOP) were elevated. Gonioscopy revealed complete angle closure in the left eye and complete to partial closure in the right eye. Through existing peripheral iridotomies the anterior capsules were seen pressed up against the iris of both eyes. A diagnosis of angle-closure glaucoma was made, medications were started to reduce the elevated intraocular pressure and systemic antihistamine to counter the allergic reaction. She was hospitalised for further management. A follow-up at 2 years revealed her visual acuities and IOP had remained normal.

Angle assessment by EyeCam, goniophotography, and gonioscopy.

PubMed

Baskaran, Mani; Perera, Shamira A; Nongpiur, Monisha E; Tun, Tin A; Park, Judy; Kumar, Rajesh S; Friedman, David S; Aung, Tin

2012-09-01

To compare EyeCam (Clarity Medical Systems, Pleasanton, CA) and goniophotography in detecting angle closure, using gonioscopy as the reference standard. In this hospital-based, prospective, cross-sectional study, participants underwent gonioscopy by a single observer, and EyeCam imaging and goniophotography by different operators. The anterior chamber angle in a quadrant was classified as closed if the posterior trabecular meshwork could not be seen. A masked observer categorized the eyes as per the number of closed quadrants, and an eye was classified as having angle closure if there were 2 or more quadrants of closure. Agreement between the methods was analyzed by κ statistic and comparison of area under receiver operating characteristic curves (AUC). Eighty-five participants (85 eyes) were included, the majority of whom were Chinese. Angle closure was detected in 38 eyes (45%) with gonioscopy, 40 eyes (47%) using EyeCam, and 40 eyes (47%) with goniophotography (P=0.69 in both comparisons, McNemar test). The agreement for angle closure diagnosis (by eye) between gonioscopy and the 2 imaging modalities was high (κ=0.86; 95% Confidence Interval (CI), 0.75-0.97), whereas the agreement between EyeCam and goniophotography was not as good (κ=0.72; 95% CI, 0.57-0.87); largely due to lack of agreement in the nasal and temporal quadrants (κ=0.55 to 0.67). The AUC for detecting eyes with gonioscopic angle closure was similar for goniophotography and EyeCam (AUC 0.93, sensitivity=94.7%, specificity=91.5%; P>0.95). EyeCam and goniophotography have similarly high sensitivity and specificity for the detection of gonioscopic angle closure.

Agreement of angle closure assessments between gonioscopy, anterior segment optical coherence tomography and spectral domain optical coherence tomography

PubMed Central

Tay, Elton Lik Tong; Yong, Vernon Khet Yau; Lim, Boon Ang; Sia, Stelson; Wong, Elizabeth Poh Ying; Yip, Leonard Wei Leon

2015-01-01

AIM To determine angle closure agreements between gonioscopy and anterior segment optical coherence tomography (AS-OCT), as well as gonioscopy and spectral domain OCT (SD-OCT). A secondary objective was to quantify inter-observer agreements of AS-OCT and SD-OCT assessments. METHODS Seventeen consecutive subjects (33 eyes) were recruited from the study hospital's Glaucoma clinic. Gonioscopy was performed by a glaucomatologist masked to OCT results. OCT images were read independently by 2 other glaucomatologists masked to gonioscopy findings as well as each other's analyses of OCT images. RESULTS Totally 84.8% and 45.5% of scleral spurs were visualized in AS-OCT and SD-OCT images respectively (P<0.01). The agreement for angle closure between AS-OCT and gonioscopy was fair at k=0.31 (95% confidence interval, CI: 0.03-0.59) and k=0.35 (95% CI: 0.07-0.63) for reader 1 and 2 respectively. The agreement for angle closure between SD-OCT and gonioscopy was fair at k=0.21 (95% CI: 0.07-0.49) and slight at k=0.17 (95% CI: 0.08-0.42) for reader 1 and 2 respectively. The inter-reader agreement for angle closure in AS-OCT images was moderate at 0.51 (95% CI: 0.13-0.88). The inter-reader agreement for angle closure in SD-OCT images was slight at 0.18 (95% CI: 0.08-0.45). CONCLUSION Significant proportion of scleral spurs were not visualised with SD-OCT imaging resulting in weaker inter-reader agreements. Identifying other angle landmarks in SD-OCT images will allow more consistent angle closure assessments. Gonioscopy and OCT imaging do not always agree in angle closure assessments but have their own advantages, and should be used together and not exclusively. PMID:25938053

Use of EyeCam for imaging the anterior chamber angle.

PubMed

Perera, Shamira A; Baskaran, Mani; Friedman, David S; Tun, Tin A; Htoon, Hla M; Kumar, Rajesh S; Aung, Tin

2010-06-01

To compare EyeCam (Clarity Medical Systems, Pleasanton, CA) imaging with gonioscopy for detecting angle closure. In this prospective, hospital-based study, subjects underwent gonioscopy by a single observer and EyeCam imaging by a different operator. EyeCam images were graded by two masked observers. The anterior chamber angle in a quadrant was classified as closed if the trabecular meshwork could not be seen. The eye was classified as having angle closure if two or more quadrants were closed. One hundred fifty-two subjects were studied. The mean age was 57.4 years (SD 12.9) and there were 82 (54%) men. Of the 152 eyes, 21 (13.8%) had angle closure. The EyeCam provided clear images of the angles in 98.8% of subjects. The agreement between the EyeCam and gonioscopy for detecting angle closure in the superior, inferior, nasal, and temporal quadrants based on agreement coefficient (AC1) statistics was 0.73, 0.75, 0.76, and 0.72, respectively. EyeCam detected more closed angles than did gonioscopy in all quadrants (P < 0.05). With gonioscopy, 21/152 (13.8%) eyes were diagnosed as angle closure compared to 41 (27.0%) of 152 with EyeCam (P < 0.001, McNemar Test), giving an overall sensitivity of 76.2% (95% confidence interval [CI], 54.9%-90.7%), specificity of 80.9% (95%CI, 73.5%-87.3%), and an area under the receiver operating characteristic curve (AUC) of 0.79. The EyeCam showed good agreement with gonioscopy for detecting angle closure. However, it detected more closed angles than did gonioscopy in all quadrants.

Undetected angle closure in patients with a diagnosis of open-angle glaucoma.

PubMed

Varma, Devesh K; Simpson, Sarah M; Rai, Amandeep S; Ahmed, Iqbal Ike K

2017-08-01

The aim of this study was to identify the proportion of patients referred to a tertiary glaucoma centre with a diagnosis of open-angle glaucoma (OAG) who were found to have angle closure glaucoma. Retrospective chart review. Consecutive new patients referred for glaucoma management to a tertiary centre between July 2010 and December 2011 were reviewed. Patients whose referrals for glaucoma assessment specified angle status as "open" were included. The data collected included glaucoma specialist's angle assessment, diagnosis, and glaucoma severity. The status of those with 180 degrees or more Shaffer angle grading of 0 was classified as "closed." From 1234 glaucoma referrals, 179 cases were specified to have a diagnosis of OAG or when angles were known to be open. Of these, 16 (8.9%) were found on examination by the glaucoma specialist to have angle closure. Pseudoexfoliation was present in 4 of 16 patients (25%) in the missed angle-closure glaucoma (ACG) group and 22 of 108 patients (13.5%) in the remaining OAG group. There was no difference found in demographic or ocular biometric parameters between those with confirmed OAG versus those with missed ACG. Almost 1 in 11 patients referred by ophthalmologists to a tertiary glaucoma centre with a diagnosis of OAG were in fact found to have angle closure. Given the different treatment approaches for ACG versus OAG, this study suggests a need to strengthen angle evaluations. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Uncertainty Analysis for Angle Calibrations Using Circle Closure

PubMed Central

Estler, W. Tyler

1998-01-01

We analyze two types of full-circle angle calibrations: a simple closure in which a single set of unknown angular segments is sequentially compared with an unknown reference angle, and a dual closure in which two divided circles are simultaneously calibrated by intercomparison. In each case, the constraint of circle closure provides auxiliary information that (1) enables a complete calibration process without reference to separately calibrated reference artifacts, and (2) serves to reduce measurement uncertainty. We derive closed-form expressions for the combined standard uncertainties of angle calibrations, following guidelines published by the International Organization for Standardization (ISO) and NIST. The analysis includes methods for the quantitative evaluation of the standard uncertainty of small angle measurement using electronic autocollimators, including the effects of calibration uncertainty and air turbulence. PMID:28009359

A Population-Based Assessment of the Agreement Between Grading of Goniophotographic Images and Gonioscopy in the Chinese-American Eye Study (CHES).

PubMed

Murakami, Yohko; Wang, Dandan; Burkemper, Bruce; Lin, Shan C; Varma, Rohit

2016-08-01

To compare grading of goniophotographic images and gonioscopy in assessing the iridocorneal angle. In a population-based, cross-sectional study, participants underwent gonioscopy and goniophotographic imaging during the same visit. The iridocorneal angle was classified as closed if the posterior trabecular meshwork could not be seen. A single masked observer graded the goniophotographic images, and each eye was classified as having angle closure based on the number of closed quadrants. Agreement between the methods was analyzed by calculating kappa (κ) and first-order agreement coefficient (AC1) statistics and comparison of area under receiver operating characteristic curves (AUC). A total of 4149 Chinese Americans (3994 eyes) were included in this study. The agreement for angle closure diagnosis between gonioscopy and EyeCam was moderate to excellent (κ = 0.60, AC1 0.90, AUC 0.76-0.80). Detection of iridocorneal angle closure based on goniophotographic imaging shows moderate to very good agreement with angle closure assessment using gonioscopy.

Anterior Chamber Angle Shape Analysis and Classification of Glaucoma in SS-OCT Images.

PubMed

Ni Ni, Soe; Tian, J; Marziliano, Pina; Wong, Hong-Tym

2014-01-01

Optical coherence tomography is a high resolution, rapid, and noninvasive diagnostic tool for angle closure glaucoma. In this paper, we present a new strategy for the classification of the angle closure glaucoma using morphological shape analysis of the iridocorneal angle. The angle structure configuration is quantified by the following six features: (1) mean of the continuous measurement of the angle opening distance; (2) area of the trapezoidal profile of the iridocorneal angle centered at Schwalbe's line; (3) mean of the iris curvature from the extracted iris image; (4) complex shape descriptor, fractal dimension, to quantify the complexity, or changes of iridocorneal angle; (5) ellipticity moment shape descriptor; and (6) triangularity moment shape descriptor. Then, the fuzzy k nearest neighbor (fkNN) classifier is utilized for classification of angle closure glaucoma. Two hundred and sixty-four swept source optical coherence tomography (SS-OCT) images from 148 patients were analyzed in this study. From the experimental results, the fkNN reveals the best classification accuracy (99.11 ± 0.76%) and AUC (0.98 ± 0.012) with the combination of fractal dimension and biometric parameters. It showed that the proposed approach has promising potential to become a computer aided diagnostic tool for angle closure glaucoma (ACG) disease.

Biometric parameters in different stages of primary angle closure using low-coherence interferometry.

PubMed

Yazdani, Shahin; Akbarian, Shadi; Pakravan, Mohammad; Doozandeh, Azadeh; Afrouzifar, Mohsen

2015-03-01

To compare ocular biometric parameters using low-coherence interferometry among siblings affected with different degrees of primary angle closure (PAC). In this cross-sectional comparative study, a total of 170 eyes of 86 siblings from 47 families underwent low-coherence interferometry (LenStar 900; Haag-Streit, Koeniz, Switzerland) to determine central corneal thickness, anterior chamber depth (ACD), aqueous depth (AD), lens thickness (LT), vitreous depth, and axial length (AL). Regression coefficients were applied to show the trend of the measured variables in different stages of angle closure. To evaluate the discriminative power of the parameters, receiver operating characteristic curves were used. Best cutoff points were selected based on the Youden index. Sensitivity, specificity, positive and negative predicative values, positive and negative likelihood ratios, and diagnostic accuracy were determined for each variable. All biometric parameters changed significantly from normal eyes to PAC suspects, PAC, and PAC glaucoma; there was a significant stepwise decrease in central corneal thickness, ACD, AD, vitreous depth, and AL, and an increase in LT and LT/AL. Anterior chamber depth and AD had the best diagnostic power for detecting angle closure; best levels of sensitivity and specificity were obtained with cutoff values of 3.11 mm for ACD and 2.57 mm for AD. Biometric parameters measured by low-coherence interferometry demonstrated a significant and stepwise change among eyes affected with various degrees of angle closure. Although the current classification scheme for angle closure is based on anatomical features, it has excellent correlation with biometric parameters.

A Population-Based Assessment of the Agreement Between Grading of Goniophotographic Images and Gonioscopy in the Chinese-American Eye Study (CHES)

PubMed Central

Murakami, Yohko; Wang, Dandan; Burkemper, Bruce; Lin, Shan C.; Varma, Rohit

2016-01-01

Purpose To compare grading of goniophotographic images and gonioscopy in assessing the iridocorneal angle. Methods In a population-based, cross-sectional study, participants underwent gonioscopy and goniophotographic imaging during the same visit. The iridocorneal angle was classified as closed if the posterior trabecular meshwork could not be seen. A single masked observer graded the goniophotographic images, and each eye was classified as having angle closure based on the number of closed quadrants. Agreement between the methods was analyzed by calculating kappa (κ) and first-order agreement coefficient (AC1) statistics and comparison of area under receiver operating characteristic curves (AUC). Results A total of 4149 Chinese Americans (3994 eyes) were included in this study. The agreement for angle closure diagnosis between gonioscopy and EyeCam was moderate to excellent (κ = 0.60, AC1 0.90, AUC 0.76–0.80). Conclusions Detection of iridocorneal angle closure based on goniophotographic imaging shows moderate to very good agreement with angle closure assessment using gonioscopy. PMID:27571018

Comparing approaches to screening for angle closure in older Chinese adults

PubMed Central

Andrews, J; Chang, D S; Jiang, Y; He, M; Foster, P J; Munoz, B; Kashiwagi, K; Friedman, D S

2012-01-01

Aims Primary angle-closure glaucoma is expected to account for nearly 50% of bilateral glaucoma blindness by 2020. This study was conducted to assess the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and limbal anterior chamber depth (LACD) as screening methods for angle closure. Methods This study assessed two clinical populations to compare SPAC, LACD, and gonioscopy: the Zhongshan Angle-closure Prevention Trial, from which 370 patients were eligible as closed-angle participants and the Liwan Eye Study, from which 72 patients were selected as open-angle controls. Eligible participants were assessed by SPAC, LACD, and gonioscopy. Results Angle status was defined by gonioscopy. Area under the receiver operating characteristic curve (AUROC) for SPAC was 0.92 (0.89–0.95) whereas AUROC for LACD was 0.94 (0.92–0.97). Using conventional cutoff points, sensitivity/specificity was 93.0%/70.8% for SPAC and 94.1%/87.5% for LACD. Sequential testing using both SPAC and LACD increased the specificity to 94.4% and decreased the sensitivity to 87.0%. Conclusion SPAC has significantly lower specificity than LACD measurement using conventional cutoffs but interpretation of the findings can be performed by modestly trained personnel. PMID:21997356

Unilateral angle-closure glaucoma with ciliochoroidal effusion after the consumption of cannabis: a case report.

PubMed

Hanna, Rana; Tiosano, Beatrice; Dbayat, Noora; Gaton, Dan

2014-01-01

A 35-year-old male patient, diagnosed with acute angle-closure glaucoma, did not improve despite intensive treatment with antiglaucoma medications. Ultrasound biomicroscopy revealed a ciliochoroidal effusion. Due to his past history of drug abuse, a urine test was analyzed and found to be positive for cannabis. After topical cycloplegia and oral steroid therapy, his symptoms improved substantially. The present case highlights the role of ultrasound biomicroscopy in evaluating patients with acute angle-closure glaucoma and the role of cannabis abuse in the development of ciliochoroidal effusion.

Association of Baseline Anterior Segment Parameters With the Development of Incident Gonioscopic Angle Closure.

PubMed

Nongpiur, Monisha E; Aboobakar, Inas F; Baskaran, Mani; Narayanaswamy, Arun; Sakata, Lisandro M; Wu, Renyi; Atalay, Eray; Friedman, David S; Aung, Tin

2017-03-01

Baseline anterior segment imaging parameters associated with incident gonioscopic angle closure, to our knowledge, are unknown. To identify baseline quantitative anterior segment optical coherence tomography parameters associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline. Three hundred forty-two participants aged 50 years or older were recruited to participate in this prospective, community-based observational study. Participants underwent gonioscopy and anterior segment optical coherence tomography imaging at baseline and after 4 years. Custom image analysis software was used to quantify anterior chamber parameters from anterior segment optical coherence tomography images. Baseline anterior segment optical coherence tomography measurements among participants with gonioscopically open vs closed angles at follow-up. Of the 342 participants, 187 (55%) were women and 297 (87%) were Chinese. The response rate was 62.4%. Forty-nine participants (14.3%) developed gonioscopic angle closure after 4 years. The mean age (SD) at baseline of the 49 participants was 62.9 (8.0) years, 15 (30.6%) were men, and 43 (87.8%) were Chinese. These participants had a smaller baseline angle opening distance at 750 µm (AOD750) (0.15 mm; 95% CI, 0.12-0.18), trabecular iris surface area at 750 µm (0.07 mm2; 95% CI, 0.05-0.08), anterior chamber area (30 mm2; 95% CI, 2.27-3.74), and anterior chamber volume (24.32 mm2; 95% CI, 18.20-30.44) (all P < .001). Baseline iris curvature (-0.08; 95% CI, -0.12 to -0.04) and lens vault (LV) measurements (-0.29 mm; 95% CI, -0.37 to -0.21) were larger among these participants ( all P < .001). A model consisting of the LV and AOD750 measurements explained 38% of the variance in gonioscopic angle closure occurring at 4 years, with LV accounting for 28% of this variance. For every 0.1 mm increase in LV and 0.1 mm decrease in AOD750, the odds of developing gonioscopic angle closure was 1.29 (95% CI, 1.07-1.57) and 3.27 (95% CI, 1.87-5.69), respectively. In terms of per SD change in LV and AOD750, this translates to an odds ratio of 2.14 (95% CI, 2.48-12.34) and 5.53 (95% CI, 1.22-3.77), respectively. A baseline LV cut-off value of >0.56 mm had 64.6% sensitivity and 84.0% specificity for identifying participants who developed angle closure. These findings suggest that smaller AOD750 and larger LV measurements are associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline.

Bilateral simultaneous acute angle closure glaucoma precipitated by non-prescription cold and flu medication.

PubMed

Rudkin, Adam K; Gray, Tim L; Awadalla, Mona; Craig, Jamie E

2010-10-01

We present a case of a 63-year-old woman who presented to an ED with bifrontal headache, nausea and vomiting and reduced visual acuity. Examination revealed bilateral elevated intraocular pressures, corneal haze, shallow anterior chambers and poorly reactive, mid-dilated pupils. Diagnosis was made of simultaneous bilateral acute angle closure glaucoma. A complete drug history revealed that she had been using an over-the-counter cold and flu remedy whose active ingredients included atropa belladonna, an herb with anticholinergic properties. It is likely that drug-induced dilatation of the individual's pupils precipitated this angle closure emergency. In the report we discuss the risk factors for angle closure glaucoma, and review the local and systemic drugs known to trigger this sight-threatening emergency. © 2010 The Authors. Emergency Medicine Australasia © 2010 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Comparison of slitlamp optical coherence tomography and scanning peripheral anterior chamber depth analyzer to evaluate angle closure in Asian eyes.

PubMed

Wong, Hon-Tym; Chua, Jocelyn L L; Sakata, Lisandro M; Wong, Melissa H Y; Aung, Han T; Aung, Tin

2009-05-01

To evaluate the effectiveness of slitlamp optical coherence tomography (SL-OCT) and Scanning Peripheral Anterior Chamber depth analyzer (SPAC) in detecting angle closure, using gonioscopy as the reference standard. A total of 153 subjects underwent gonioscopy, SL-OCT, and SPAC. The anterior chamber angle (ACA) was classified as closed on gonioscopy if the posterior trabecular meshwork could not be seen; with SL-OCT, closure was determined by contact between the iris and angle wall anterior to the scleral spur; and with SPAC by a numerical grade of 5 or fewer and/or a categorical grade of suspect or potential. A closed ACA was identified in 51 eyes with gonioscopy, 86 eyes with SL-OCT, and 61 eyes with SPAC (gonioscopy vs SL-OCT, P < .001; gonioscopy vs SPAC, P = .10; SL-OCT vs SPAC, P < .001; McNemar test). Of the 51 eyes with a closed ACA on gonioscopy, SL-OCT detected a closed ACA in 43, whereas SPAC identified 41 (P = .79). An open angle in all 4 quadrants was observed in 102 eyes with gonioscopy, but SL-OCT and SPAC identified 43 and 20 of these eyes, respectively, as having angle closure. The overall sensitivity and specificity for SL-OCT were 84% and 58% vs 80% and 80% for SPAC. Using gonioscopy as the reference, SL-OCT and SPAC showed good sensitivity for detecting eyes at risk of angle closure.

Glaucoma

MedlinePlus

Open-angle glaucoma; Chronic glaucoma; Chronic open-angle glaucoma; Primary open-angle glaucoma; Closed-angle glaucoma; Narrow-angle glaucoma; Angle-closure glaucoma; Acute glaucoma; Secondary glaucoma; Congenital glaucoma; Vision ...

Assessment of narrow angles by gonioscopy, Van Herick method and anterior segment optical coherence tomography.

PubMed

Park, Seong Bae; Sung, Kyung Rim; Kang, Sung Yung; Jo, Jung Woo; Lee, Kyoung Sub; Kook, Michael S

2011-07-01

To evaluate anterior chamber (AC) angles using gonioscopy, Van Herick technique and anterior segment optical coherence tomography (AS-OCT). One hundred forty-eight consecutive subjects were enrolled. The agreement between any two of three diagnostic methods, gonioscopy, AS-OCT and Van Herick, was calculated in narrow-angle patients. The area under receiver-operating characteristic curves (AUC) for discriminating between narrow and open angles determined by gonioscopy was calculated in all participants for AS-OCT parameter angle opening distance (AOD), angle recess area, trabecular iris surface area and anterior chamber depth (ACD). As a subgroup analysis, capability of AS-OCT parameters for detecting angle closure defined by AS-OCT was assessed in narrow-angle patients. The agreement between the Van Herick method and gonioscopy in detecting angle closure was excellent in narrow angles (κ = 0.80, temporal; κ = 0.82, nasal). However, agreement between gonioscopy and AS-OCT and between the Van Herick method and AS-OCT was poor (κ = 0.11-0.16). Discrimination capability of AS-OCT parameters between open and narrow angles determined by gonioscopy was excellent for all AS-OCT parameters (AUC, temporal: AOD500 = 0.96, nasal: AOD500 = 0.99). The AUCs for detecting angle closure defined by AS-OCT image in narrow angle subjects was good for all AS-OCT parameters (AUC, 0.80-0.94) except for ACD (temporal: ACD = 0.70, nasal: ACD = 0.63). Assessment of narrow angles by gonioscopy and the Van Herick technique showed good agreement, but both measurements revealed poor agreement with AS-OCT. The angle closure detection capability of AS-OCT parameters was excellent; however, it was slightly lower in ACD.

Unilateral Angle-Closure Glaucoma with Ciliochoroidal Effusion after the Consumption of Cannabis: A Case Report

PubMed Central

Hanna, Rana; Tiosano, Beatrice; Dbayat, Noora; Gaton, Dan

2014-01-01

A 35-year-old male patient, diagnosed with acute angle-closure glaucoma, did not improve despite intensive treatment with antiglaucoma medications. Ultrasound biomicroscopy revealed a ciliochoroidal effusion. Due to his past history of drug abuse, a urine test was analyzed and found to be positive for cannabis. After topical cycloplegia and oral steroid therapy, his symptoms improved substantially. The present case highlights the role of ultrasound biomicroscopy in evaluating patients with acute angle-closure glaucoma and the role of cannabis abuse in the development of ciliochoroidal effusion. PMID:25606036

Resident-performed laser peripheral iridotomy in primary angle closure, primary angle closure suspects, and primary angle closure glaucoma.

PubMed

Kam, Jason P; Zepeda, Emily M; Ding, Leona; Wen, Joanne C

2017-01-01

To investigate the power use and complication frequency of resident-performed laser peripheral iridotomy (LPI). A retrospective analysis of 196 eyes from 103 patients who underwent neodymium: yttrium-aluminum-garnet laser iridotomy performed by resident physicians from January 1, 2010 through April 30, 2015 at a university-based county hospital was done. All patients were treated for primary angle closure, primary angle closure suspects, and primary angle closure glaucoma. Data were collected on pre- and post-laser intraocular pressure (IOP), ethnicity, laser parameters and complications. Mean power use and frequency of complications were evaluated. Complications included elevated post-laser IOP at 30-45 minutes (≥8 mmHg), hyphema, aborted procedures, and lasering non-iris structures. The number of repeated LPI procedures, was also recorded. Mean total power used for all residents was 78.2±68.7 mJ per eye. Power use by first-year trainees was significantly higher than second- and third-year trainees (103.5±75.5 mJ versus 73.7±73.8 mJ and 67.2±56.4 mJ, respectively, p =0.011). Complications included hyphema or microhyphema in 17.9% (35/196), IOP spikes in 5.1% (10/196), aborted procedures in 1.1% (3/196) and lasering non-iris structures in 0.5% (1/196). LPI was repeated in 22.4% of cases (44/196) with higher incidence of repeat LPI among non-Caucasian compared to the Caucasian subjects ( p =0.02). Complication rates did not differ with increased training ( p =0.16). Total power used for LPI decreased with increased resident training, while the complication rate did not differ significantly among resident classes. Complication rates were comparable to rates reported in the literature for attending-performed LPIs.

Evaluation of circumferential angle closure using iridotrabecular contact index after laser iridotomy by swept-source optical coherence tomography.

PubMed

Cho, Hyun-Kyung; Ahn, Dongsub; Kee, Changwon

2017-05-01

To investigate the quantitative changes of circumferential angle closure after laser iridotomy (LI) using the iridotrabecular contact (ITC) index by Swept-Source optical coherence tomography (OCT). In this prospective observational study conducted in a hospital setting, 42 eyes of 36 patients (five males, 31 females) who underwent LI were included. The mean age was 65.00 ± 8.13 years old and the diagnosis included primary angle closure (PAC, 21 eyes), PAC suspect (16 eyes) and PAC glaucoma (five eyes). Optical coherence tomography (OCT) images were obtained pre-LI and at 1 week post-LI. In each image frame, the scleral spur (SS) and the ITC end-point were marked, from which the ITC index was calculated as a percentage of the angle closure across 360°. Measurements inspected before and after LI included: central anterior chamber depth (ACD), anterior chamber volume (ACV), lens vault (LV), nasal and temporal angle opening distance (AOD), angle recess area (ARA), trabecular-iris space area (TISA), trabecular-iris angle (TIA) at 500 μm and 750 μm from the SS and intraocular pressure (IOP). The ITC index and IOP decreased significantly after LI from 71.52 ± 26.29 to 35.31 ± 27.19 and from 20.64 ± 12.72 mmHg to 14.02 ± 3.49 mmHg, respectively (p < 0.001 and p < 0.001). Central ACD (1.94 ± 0.31 mm pre-LI) and LV (1.13 ± 0.32 mm pre-LI) did not show a significant change after LI (all p > 0.05), but ACV increased significantly after LI (p < 0.001). Most of the angle parameters except for nasal TIAs increased significantly after LI (all p < 0.05). The ITC index from patients with shallow anterior chamber angle showed a significant decrease after LI, but part of the angle closure was not relieved after LI. Other mechanisms besides pupillary block may play a role together in causing angle closure. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

38 CFR 4.79 - Schedule of ratings-eye.

Code of Federal Regulations, 2012 CFR

2012-07-01

... retina. 6009Unhealed eye injury. General Rating Formula for Diagnostic Codes 6000 through 6009 Evaluate... irregularities, if this would result in a higher evaluation. 6012Angle-closure glaucoma: Evaluate on the basis of either visual impairment due to angle-closure glaucoma or incapacitating episodes, whichever results in a...

38 CFR 4.79 - Schedule of ratings-eye.

Code of Federal Regulations, 2013 CFR

2013-07-01

... retina. 6009Unhealed eye injury. General Rating Formula for Diagnostic Codes 6000 through 6009 Evaluate... irregularities, if this would result in a higher evaluation. 6012Angle-closure glaucoma: Evaluate on the basis of either visual impairment due to angle-closure glaucoma or incapacitating episodes, whichever results in a...

38 CFR 4.79 - Schedule of ratings-eye.

Code of Federal Regulations, 2014 CFR

2014-07-01

... retina. 6009Unhealed eye injury. General Rating Formula for Diagnostic Codes 6000 through 6009 Evaluate... irregularities, if this would result in a higher evaluation. 6012Angle-closure glaucoma: Evaluate on the basis of either visual impairment due to angle-closure glaucoma or incapacitating episodes, whichever results in a...

Bilateral nanophthalmos, pigmentary retinal dystrophy, and angle closure glaucoma--a new syndrome?

PubMed Central

Ghose, S; Sachdev, M S; Kumar, H

1985-01-01

An unusual case of bilateral nanophthalmos with pigmentary retinal dystrophy and angle closure glaucoma is presented. This is probably the first published report of the established association of all these three entities in the same patient. The aetiological possibilities and clinical significance are discussed. Images PMID:4016062

[Two cases of Vogt-Koyanagi-Harada disease presenting shallow anterior chamber].

PubMed

Takemoto, Daisuke; Ijiri, Shigeyuki; Shimizu, Michiharu; Higashide, Tomomi; Sugiyama, Kazuhisa

2015-05-01

We report two cases of Vogt-Koyanagi-Harada disease (VKH) in which shallow anterior chambers were improved after steroid pulse therapy. The patients were women aged 65 and 72. They had headaches, decreased visual acuity and shallow anterior chamber in both eyes. There was no inflammation in the anterior chamber. Ultrasound biomicroscopy (UBM) showed ciliary edema, ciliochoroidal detachment, and angle closure. One case showed high intraocular pressure (IOP), and a diagnosis of acute primary angle closure was made. Although cataract surgery was performed in the left eye, postoperative optical coherence tomography (OCT) revealed serous retinal detachment in both eyes. The shallow anterior chamber and UBM findings were improved and serous retinal detachment disappeared after steroid pulse therapy in both cases. VKH may cause shallow anterior chamber and angle closure. The inflammatory changes of VKH in the anterior segment, i. e. ciliary edema and ciliochoroidal detachment, may exacerbate the shallow anterior chambers and narrow angles and result in an acute increase in IOP in eyes with short axial length. VKH associated with shallow anterior chamber may be misdiagnosed as acute primary angle closure. For differential diagnosis, examinations of the ocular fundus including OCT are useful.

Gonioscopy findings and prevalence of occludable angles in a Burmese population: the Meiktila Eye Study

PubMed Central

Casson, R J; Newland, H S; Muecke, J; McGovern, S; Abraham, L M; Shein, W K; Selva, D; Aung, T

2007-01-01

Aim To determine the prevalence of preglaucomatous angle‐closure disease in central Myanmar. Methods A population‐based survey of inhabitants ⩾40 years in the Meiktila District was carried out; 2481 subjects were identified, 2076 participated and 2060 underwent gonioscopy of at least one eye. Eyes with angles traditionally described as “occludable” were recorded as primary angle‐closure suspects (PACS); eyes with PACS and peripheral anterior synechiae (PAS), or an increased intraocular pressure but without primary angle‐closure glaucoma, were recorded as primary angle closure (PAC). Results The prevalence of PACS in at least one eye was 5.7% (95% CI 4.72 to 6.62); prevalence increased with age and was more common in women (p<0.001). The prevalence of PAC in at least one eye was 1.50% (95% CI 1.47 to 1.53). All participants with PAS had at least 90° of closure (range 90–360°). Conclusion The prevalence of preglaucomatous angle‐closure disease (PACS and PAC) in this population was 5.7% and 1.5%, respectively. PACS was more common in women, and its prevalence increased with age. PMID:17576708

Effect of afterbody geometry on aerodynamic characteristics of isolated nonaxisymmetric afterbodies at transonic Mach numbers

NASA Technical Reports Server (NTRS)

Bangert, Linda S.; Carson, George T., Jr.

1992-01-01

A parametric study was conducted in the Langley 16-Foot Transonic Tunnel on an isolated nonaxisymmetic fuselage model that simulates a twin-engine fighter. The effects of aft-end closure distribution (top/bottom) nozzle-flap boattail angle versus nozzle-sidewall boattail angle) and afterbody and nozzle corner treatment (sharp or radius) were investigated. Four different closure distributions with three different corner radii were tested. Tests were conducted over a range of Mach numbers from 0.40 to 1.25 and over a range of angles of attack from -3 to 9 degrees. Solid plume simulators were used to simulate the jet exhaust. For a given closure distribution in the range of Mach numbers tested, the sharp-corner nozzles generally had the highest drag, and the 2-in. corner-radius nozzles generally had the lowest drag. The effect of closure distribution on afterbody drag was highly dependent on configuration and flight condition.

Setting priorities for comparative effectiveness research on management of primary angle closure: a survey of Asia-Pacific clinicians.

PubMed

Yu, Tsung; Li, Tianjing; Lee, Kinbo J; Friedman, David S; Dickersin, Kay; Puhan, Milo A

2015-01-01

To set priorities for new systematic reviews (SRs) and randomized clinical trials on the management of primary angle closure (PAC) using clinical practice guidelines and a survey of Asia-Pacific clinicians. We restated the American Academy of Ophthalmology's Preferred Practice Patterns recommendations for management of PAC into answerable clinical questions. We asked participants at the Asia-Pacific Joint Glaucoma Congress 2010 in Taipei to rate the importance of having an answer to each question for providing effective patient care, using a Likert-type scale and scoring from 0 (not important at all) to 10 (highly important). We identified relevant SRs and mapped the evidence to clinical questions to identify evidence gaps. We generated 42 clinical questions. One hundred seventy-five individuals agreed to participate in the survey, 132 responded (75.4% response rate) and 96 completed the questionnaire (54.9% usable response rate). Questions rated important include laser iridotomy for the prevention of angle closure in primary angle-closure suspects, further therapies in eyes with plateau iris syndrome after laser iridotomy, and evaluation of the fellow eye in acute angle-closure patients for improving prognosis. Up-to-date and conclusive SR evidence was not available for any of the 42 clinical questions. We identified high priority clinical questions on the management of PAC, none of which had reliable SR evidence available. New SRs and randomized clinical trials can be initiated to address these evidence gaps.

Soap Gets in Your Eyes

PubMed Central

Laidlaw, Alistair; Bloom, Philip

1990-01-01

We present a previously unreported series of five cases of acute angle closure glaucoma associated with watching the Australia soap opera "Neighbours". Two cases were bilateral and associated with watching two episodes of "Neighbours" on the same day. The pathogenesis, and possible role of watching soap operas in the causation of primary angle closure glaucoma is discussed. PMID:1369543

Anterior Segment Morphology in Primary Angle Closure Glaucoma using Ultrasound Biomicroscopy

PubMed Central

Balakrishna, Nagalla

2017-01-01

Aim To evaluate the configuration of the anterior chamber angle quantitatively and study the morphological changes in the eye with ultrasound biomicroscopy (UBM) in primary angle closure glaucoma (PACG) patients after laser peripheral iridotomy (LPI). Materials and methods A total of 185 eyes of 185 PACG patients post-LPI and 126 eyes of 126 normal subjects were included in this prospective study. All subjects underwent complete ophthalmic evaluation, A-scan biometry, and UBM. The anterior segment and angle parameters were measured quantitatively and compared in both groups using Student’s t-test. Results The PACG patients had shorter axial length, shallower central anterior chamber depth anterior chamber depth (ACD), and anteriorly located lens when compared with normal subjects. Trabecular iris angle (TIA) was significantly narrow (5.73 ± 7.76°) in patients with PACG when compared with normal subjects (23.75 ± 9.38°). The angle opening distance at 500 pm from scleral spur (AOD 500), trabecular-ciliary process distance (TCPD), iris-ciliary process distance (ICPD), and iris-zonule distance (IZD) were significantly shorter in patients with PACG than in normal subjects (p < 0.0001). The iris lens angle (ILA), scleral-iris angle (SIA), and scleral-ciliary process angle (SCPA) were significantly narrower in patients with PACG than in normal subjects (p < 0.0001). The iris-lens contact distance (ILCD) was greater in PACG group than in normal (p = 0.001). Plateau iris was seen in 57/185 (30.8%) of the eyes. Anterior positioned ciliary processes were seen in 130/185 eyes (70.3%) of eyes. Conclusion In PACG patients, persistent apposition angle closure is common even after LPI, which could be due to anterior rotation of ciliary body and plateau iris and overcrowding of anterior segment due to shorter axial length and relative anterior lens position. How to cite this article: Mansoori T, Balakrishna N. Anterior Segment Morphology in Primary Angle Closure Glaucoma using Ultrasound Biomicroscopy. J Curr Glaucoma Pract 2017;11(3):86-91. PMID:29151682

Gonioscopy in primary angle closure glaucoma.

PubMed

Bruno, Christina A; Alward, Wallace L M

2002-06-01

Primary angle closure is a condition characterized by obstruction to aqueous humor outflow by the peripheral iris, and results in changes in the iridocorneal angle that are visible through gonioscopic examination. Gonioscopy in these eyes, however, can be difficult. This chapter discusses techniques that might help in the examination. These include beginning the examination with the inferior angle, methods to help in looking over the iris, cycloplegia, locating the corneal wedge, indentation, van Herick estimation, examining the other eye, and topical glycerin. Finally, there is a discussion about the pathology associated with the closed angle, with emphasis on the appearance of iris bombé, plateau iris, and the distinction between iris processes and peripheral anterior synechiae.

Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma.

PubMed

Masis, Marisse; Chen, Rebecca; Porco, Travis; Lin, Shan C

2017-11-01

To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes. Prospective, cross-sectional clinical study. Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects. The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008). In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

Amplatzer angled duct occluder for closure of patent ductus arteriosus larger than the aorta in an infant.

PubMed

Vijayalakshmi, I B; Chitra, N; Rajasri, R; Prabhudeva, A N

2005-01-01

Transcatheter closure of patent ductus arteriosus (PDA) by Amplatzer duct occluder is the treatment of choice. However, closure of very large ducts in infants with low weight is a challenge for the interventionalist because a large device may obstruct the aorta or left pulmonary artery. Difficulty is also encountered in advancing the device around the curve of the right ventricular outflow tract toward the pulmonary artery; this curve is tight, more or less at a right angle in infants, leading to kinking of the sheath, which increases fluoroscopic time. This is the first reported case of a very large PDA (8.7 mm), larger than the aorta (8.2 mm), successfully closed by an Amplatzer angled duct occluder in an infant weighing 5 kg.

[Correlation analysis of hearing level and soft palate movement after palatoplasty].

PubMed

Lou, Qun; Ma, Xiaoran; Ma, Lian; Luo, Yi; Zhu, Hongping; Zhou, Zhibo

2015-10-01

To explore the relationship between hearing level and soft palate movement after palatoplasty and to verify the importance of recovery of soft palate movement function for improving the middle ear function as well as reducing the hearing loss. A total of 64 non-syndromic cleft palate patients were selected and the lateral cephalometric radiographs were taken. The patients hearing level was evaluated by the pure tone hearing threshold examination. This study also analyzed the correlation between hearing threshold of the patients after palatoplasty and the soft palate elevation angle and velopharyngeal rate respectively. Kendall correlation analysis revealed that the correlation coefficient between hearing threshold and the soft palate elevation angle after palatoplasty was -0.339 (r = -0.339, P < 0.01).The correlation showed a negative correlation. The hearing threshold decreased as the soft palate elevation angle increased. After palatoplasty, the correlation coefficient between the hearing threshold and the rate of velopharyngeal closure was -0.277 (r = -0.277, P < 0.01). The correlation showed a negative correlation. While, The hearing threshold decreased with the increase of velopharyngeal closure rate. The hearing threshold was correlated with soft palate elevation angle and velpharyngeal closure rate. The movement of soft palate and velopharyngeal closure function after palatoplasty both have impact on patient hearing level. In terms of the influence level, the movement of soft palate has a higher level of impact on patient hearing level than velopharygeal closure function.

Role of macular hole angle in macular hole closure.

PubMed

Chhablani, Jay; Khodani, Mitali; Hussein, Abdullah; Bondalapati, Sailaja; Rao, Harsha B; Narayanan, Raja; Sudhalkar, Aditya

2015-12-01

To evaluate correlation of various spectral-domain optical coherence tomography (SD-OCT) parameters including macular hole angle as well as various indices with anatomical and visual outcomes after idiopathic macular hole repair surgery. Retrospective study of 137 eyes of 137 patients who underwent idiopathic macular hole repair surgery between January 2008 and January 2014 was performed. Various qualitative parameters such as presence of vitreomacular traction, epiretinal membrane and cystic edges at the macular hole as well as quantitative parameters such as maximum diameter on the apex of the hole, minimum diameter between edges, nasal and temporal vertical height, longest base diameter and macular hole angle between the retinal edge and the retinal pigment epithelium were noted. Indices including hole form factor, Macular Hole Index (MHI), Diameter Hole Index and Tractional Hole Index (THI) were calculated. Univariate and multivariate regression analysis was performed separately for final visual acuity (VA) and type of closure as dependent variable in relation to SD-OCT parameters as independent variables. On multivariate regression only minimum diameter between edges (p≤0.01) and longest base diameter (p≤0.03) were correlated significantly with both, type 1 closure and final VA. Among the indices, significant correlation of MHI (p=0.009) was noted with type of closure and that of THI with final VA (p=0.017). Our study shows no significant correlation between macular hole angle and hole closure. Minimum diameter between the edges and longest diameter of the hole are best predictors of hole closure and postoperative VA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Longitudinal changes of angle configuration in primary angle-closure suspects: the Zhongshan Angle-Closure Prevention Trial.

PubMed

Jiang, Yuzhen; Chang, Dolly S; Zhu, Haogang; Khawaja, Anthony P; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M; He, Mingguang; Friedman, David S; Foster, Paul J

2014-09-01

To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Longitudinal cohort study. Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8-1.6) in treated eyes and 1.6°/year (95% CI, 1.3-2.0) in untreated eyes (P<0.001). Angle width of treated eyes increased markedly after LPI, remained stable for 6 months, and then decreased significantly by 18 months after LPI. Untreated eyes experienced a more consistent and rapid decrease in angle width over the same time period. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Gonioscopy and ultrasound biomicroscopy in the detection of angle closure in patients with shallow anterior chamber.

PubMed

Cui, Shan-shan; Zou, Yan-hong; Li, Qian; Li, Li-na; Zhang, Ning; Liu, Xi-pu

2014-12-01

To assess the agreement between gonioscopy and ultrasound biomicroscopy (UBM) in detecting angle closure in Chinese patients with shallow anterior chamber. An observational comparative study of the two different examination methods was conducted. Patients with normal intraocular pressure and temporal peripheral anterior chamber depth less than a quarter of corneal thickness based on slit lamp examination were included in this study from December 2007 to May 2009 in the outpatient clinic of First Hospital of Tsinghua University. Gonioscopy was performed with a Goldman goniolens in dark room first and followed by full beam light and indentation. If the filtering trabecular meshwork was invisible or any peripheral anterior synechia was found, that quadrant of the angle was considered closed. UBM was first undertaken in a darkened room then repeated with normal room lighting. If iridotrabecular apposition was showed, that quadrant of the angle was considered closed. The status of angle closure of each quadrant with different methods was recorded. 85 eyes of 46 patients were included in this study. The agreement between gonioscopy and UBM was poor (Κ<0.4) with Kappa analysis in both dark and light conditions in each quadrant. The accordance of agreement between gonioscopy and UBM was hardly affected by age or sex, while in dark condition, eyes with deeper anterior chamber (P=0.005) or plateau iris configuration tended to produce different results (P=0.075) in the 2 methods. Gonioscopy and UBM are both indispensable methods for detecting angle closure, neither can completely replace the other.

Case report: imaging and treatment of ophthalmic manifestations in oculodentodigital dysplasia.

PubMed

Mosaed, Sameh; Jacobsen, Bradley H; Lin, Ken Young

2016-01-07

Diagnostic and surgical management of severe chronic angle- closure glaucoma secondary to ciliary body cysts can be difficult to manage in a patient with oculodentodigital dysplasia. A 6-year old girl with oculodentodigital dysplasia, with progressive chronic angle- closure glaucoma secondary to ciliary body cysts presented to our clinic. The initial examination revealed counting fingers vision in the left eye. Intraocular pressure (IOP), as assessed by tonopen, was 31 mm Hg. Ultrasound biomicroscopy revealed ciliary body cysts in the left eye, and gonioscopy confirmed chronic angle closure. A tube shunt was placed to control the elevated IOP. A year after her tube shunt placement in the left eye, ultrasound biomiscropy was performed on her right eye and showed no ciliary body cysts. Gonioscopy in the right eye revealed an open angle to the ciliary body band. Subsequent serial gonioscopy every 3 months showed gradual narrowing of the right eye angle and finally three-and-a-half years after tube placement of the left eye, her right eye IOP became uncontrolled with medications alone and a tube shunt was similarly placed in the right eye. Intraoperative ultrasound biomicroscopy performed at the time of the right eye tube shunt revealed extensive ciliary body cysts in the right eye. Her IOP in both eyes have been well controlled since the placement of tube shunts. This is one of the first reported cases of severe chronic angle- closure glaucoma secondary to ciliary body cysts in a patient with oculodentodigital dysplasia. We believe that early screening for ciliary body cysts is important in patients with oculodentodigital dysplasia.

Anterior chamber angle imaging with swept-source optical coherence tomography: measuring peripheral anterior synechia in glaucoma.

PubMed

Lai, Isabel; Mak, Heather; Lai, Gilda; Yu, Marco; Lam, Dennis S C; Leung, Christopher K S

2013-06-01

To investigate the use of swept-source optical coherence tomography (OCT) for measuring the area and degree of peripheral anterior synechia (PAS) involvement in patients with angle-closure glaucoma. Cross-sectional study. Twenty-three eyes with PAS (detected by indentation gonioscopy) from 20 patients with angle-closure glaucoma (20 eyes had primary angle-closure glaucoma and 3 eyes had angle-closure glaucoma secondary to chronic anterior uveitis [n = 2] and Axenfeld-Rieger syndrome [n = 1]). The anterior chamber angles were evaluated with indentation gonioscopy and imaged by swept-source OCT (Casia OCT, Tomey, Nagoya, Japan) in room light and in the dark using the "angle analysis" protocol, which was composed of 128 radial B-scans each with 512 A-scans (16-mm scan length). The area and degree of PAS involvement were measured in each eye after manual detection of the scleral spur and the anterior irido-angle adhesion by 2 masked observers. The interobserver variability of the PAS measurements was calculated. The agreement of PAS assessment by gonioscopy and OCT, the area and the degree of PAS involvement, and the intraclass correlation coefficient (ICC) of interobserver PAS measurements. The area of PAS (mean ± standard deviation) was 20.8 ± 16.9 mm(2) (range, 3.9-74.9 mm(2)), and the degree of PAS involvement was 186.5 ± 79.9 degrees (range, 42-314 degrees). There was no difference in the area of PAS (P = 0.90) and the degree of PAS involvement (P = 0.95) between images obtained in room light and in the dark. The interobserver ICCs were 0.99 (95% confidence interval [CI], 0.98-1.00) for the area of PAS and 0.99 (95% CI, 0.97-1.00) for the degree of PAS involvement. There was good agreement of PAS assessment between gonioscopy and OCT images (kappa = 0.79; 95% CI, 0.67-0.91). Swept-source OCT allows visualization and reproducible measurements of the area and degree of PAS involvement, providing a new paradigm for evaluation of PAS progression and risk assessment for development of angle-closure glaucoma. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Secondary angle closure caused by air migrating behind the pupil in descemet stripping endothelial keratoplasty.

PubMed

Lee, Jung S; Desai, Neel R; Schmidt, Gregory W; Jun, Albert S; Schein, Oliver D; Stark, Walter J; Eghrari, Allen O; Gottsch, John D

2009-07-01

To report secondary angle closure caused by air migrating behind the pupil in the context of intraocular pressure (IOP) elevation in the early postoperative period after Descemet stripping endothelial keratoplasty (DSEK). A retrospective case series was conducted on 100 consecutive DSEK cases from 90 patients undergoing DSEK because of corneal disease from Fuchs corneal dystrophy, pseudophakic bullous keratopathy, aphakic bullous keratopathy, and iridocorneal endothelial syndrome. Preoperative and postoperative slit-lamp examinations and IOP measurements were ascertained for all 100 eyes. Main outcome measures included preoperative and postoperative IOP. Thirteen of 100 eyes developed an IOP rise of greater than 30 mm Hg on the first postoperative day. Six of these 13 patients developed angle closure from air migrating posterior to the iris and causing iridocorneal adhesions. One of these 13 patients developed pupillary block from air anterior to iris. Six of 13 patients developed increased IOP without pupillary block or iridocorneal adhesions and had a history of preexisting primary or secondary glaucoma. A secondary angle closure associated with DSEK is reported with air migrating behind the iris, resulting in extensive iridocorneal adhesions. An acute increase in IOP after DSEK can also be induced by air anterior to the iris causing pupillary block. IOP spikes are much more common in the first few postoperative days after DSEK. Medical treatment can occasionally resolve air posterior to the iris, but if iridocorneal adhesions are extensive and persistent, air removal and angle reformation may be necessary.

Bilateral acute angle closure glaucoma after hyperopic LASIK correction

PubMed Central

Osman, Essam A.; Alsaleh, Ahmed A.; Al Turki, Turki; AL Obeidan, Saleh A.

2009-01-01

Acute angle closure glaucoma is unexpected complication following laser in situ keratomileusis (LASIK). We are reporting a 49-years-old lady that was presented to the emergency department with acute glaucoma in both eyes soon after LASIK correction. Diagnosis was made on detailed clinical history and examination, slit lamp examination, intraocular pressure measurement and gonioscopy. Laser iridotomy in both eyes succeeded in controlling the attack and normalizing the intraocular pressure (IOP) more than 6 months of follow-up. Prophylactic laser iridotomy is essential for narrow angle patients before LASIK surgery if refractive laser surgery is indicated. PMID:23960863

Cranial Suture Closure in Domestic Dog Breeds and Its Relationships to Skull Morphology.

PubMed

Geiger, Madeleine; Haussman, Sinah

2016-04-01

Bulldog-type brachycephalic domestic dog breeds are characterized by a relatively short and broad skull with a dorsally rotated rostrum (airorhynchy). Not much is known about the association between a bulldog-type skull conformation and peculiar patterns of suture and synchondrosis closure in domestic dogs. In this study, we aim to explore breed-specific patterns of cranial suture and synchondrosis closure in relation to the prebasial angle (proxy for airorhynchy and thus bulldog-type skull conformation) in domestic dogs. For this purpose, we coded closure of 18 sutures and synchondroses in 26 wolves, that is, the wild ancestor of all domestic dogs, and 134 domestic dogs comprising 11 breeds. Comparisons of the relative amount of closing and closed sutures and synchondroses (closure scores) in adult individuals showed that bulldog-type breeds have significantly higher closure scores than non-bulldog-type breeds and that domestic dogs have significantly higher closure scores than the wolf. We further found that the prebasial angle is significantly positively correlated with the amount of closure of the basispheno-presphenoid synchondrosis and sutures of the nose (premaxillo-nasal and maxillo-nasal) and the palate (premaxillo-maxillary and interpalatine). Our results show that there is a correlation between patterns of suture and synchondrosis closure and skull shape in domestic dogs, although the causal relationships remain elusive. © 2016 Wiley Periodicals, Inc.

Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial.

PubMed

Azuara-Blanco, Augusto; Burr, Jennifer; Ramsay, Craig; Cooper, David; Foster, Paul J; Friedman, David S; Scotland, Graham; Javanbakht, Mehdi; Cochrane, Claire; Norrie, John

2016-10-01

Primary angle-closure glaucoma is a leading cause of irreversible blindness worldwide. In early-stage disease, intraocular pressure is raised without visual loss. Because the crystalline lens has a major mechanistic role, lens extraction might be a useful initial treatment. From Jan 8, 2009, to Dec 28, 2011, we enrolled patients from 30 hospital eye services in five countries. Randomisation was done by a web-based application. Patients were assigned to undergo clear-lens extraction or receive standard care with laser peripheral iridotomy and topical medical treatment. Eligible patients were aged 50 years or older, did not have cataracts, and had newly diagnosed primary angle closure with intraocular pressure 30 mm Hg or greater or primary angle-closure glaucoma. The co-primary endpoints were patient-reported health status, intraocular pressure, and incremental cost-effectiveness ratio per quality-adjusted life-year gained 36 months after treatment. Analysis was by intention to treat. This study is registered, number ISRCTN44464607. Of 419 participants enrolled, 155 had primary angle closure and 263 primary angle-closure glaucoma. 208 were assigned to clear-lens extraction and 211 to standard care, of whom 351 (84%) had complete data on health status and 366 (87%) on intraocular pressure. The mean health status score (0·87 [SD 0·12]), assessed with the European Quality of Life-5 Dimensions questionnaire, was 0·052 higher (95% CI 0·015-0·088, p=0·005) and mean intraocular pressure (16·6 [SD 3·5] mm Hg) 1·18 mm Hg lower (95% CI -1·99 to -0·38, p=0·004) after clear-lens extraction than after standard care. The incremental cost-effectiveness ratio was £14 284 for initial lens extraction versus standard care. Irreversible loss of vision occurred in one participant who underwent clear-lens extraction and three who received standard care. No patients had serious adverse events. Clear-lens extraction showed greater efficacy and was more cost-effective than laser peripheral iridotomy, and should be considered as an option for first-line treatment. Medical Research Council. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.

Water-drinking test in primary angle-closure suspect before and after laser peripheral iridotomy.

PubMed

Waisbourd, Michael; Savant, Shravan V; Sun, Yi; Martinez, Patricia; Myers, Jonathan S

2016-03-01

This study aimed to investigate whether performing a laser peripheral iridotomy in primary angle-closure suspects had an effect on the intraocular pressure response during the water-drinking test. Prospective study in a hospital setting. Primary angle-closure suspects scheduled for a laser peripheral iridotomy. Primary angle-closure suspects were evaluated before the laser peripheral iridotomy and 2 weeks after. On each visit, subjects underwent the water-drinking test. Intraocular pressure was measured every 15 min within a 1-h period. Intraocular pressure fluctuations during the water drinking test. Twenty patients were enrolled. The mean age was 58.1 years (±10.2 SD), predominantly female (n = 14, 70%). Average intraocular pressure range (maximum-minimum) during the water-drinking test increased significantly from 2.6 ± 1.1 mmHg before the laser peripheral iridotomy to 3.5 ± 1.5 mmHg after (P = 0.04). The mean difference between peak and last intraocular pressure measurements increased after the laser peripheral iridotomy was performed, from 2.5 mmHg (±1.27 SD) to 3.3 mmHg (±1.66 SD), (P = 0.057). There was no change in mean peak intraocular pressure (maximum-baseline) before and after the laser peripheral iridotomy (P = 0.87). Primary angle-closure suspects who underwent the water-drinking test had a slightly more pronounced recovery of intraocular pressure after the laser peripheral iridotomy was performed, which may be attributed to increase in the area of exposed trabecular meshwork following treatment. Differences in intraocular pressure curves before and after laser peripheral iridotomy were minimal, and therefore, the water-drinking test had limited value as a provocative test in this patient population. © 2015 Royal Australian and New Zealand College of Ophthalmologists.

Microwave-superheated Vics Vapo Rub: an ocular public health danger.

PubMed

Fung, Anne E; Oxford, Karen W

2004-02-01

To report a case of a microwave-oven superheated petroleum-based liquid causing severe chemical and thermal ocular burns treated successfully with amniotic membrane transplantation. Observational case report. Retrospective review of clinical case. A 77-year-old woman sustained a severe combined chemical and thermal burn from microwave-heated Vicks Vapo-Rub requiring amniotic membrane transplant, with subsequent development of phacomorphic glaucoma, requiring cataract extraction, and bullous keratopathy, requiring penetrating keratoplasty. As microwave oven use becomes more commonplace, the risk of superheating liquids becomes an increasingly significant ocular danger. Continued efforts to educate the public about safe microwave use is necessary. Additionally, amniotic membrane transplantation was found to be effective in managing a combined chemical and thermal ocular burn.

Changes in Anterior Segment Morphology and Predictors of Angle Widening after Laser Iridotomy in South Indian Eyes.

PubMed

Zebardast, Nazlee; Kavitha, Srinivasan; Krishnamurthy, Palaniswamy; Friedman, David S; Nongpiur, Monisha E; Aung, Tin; Quigley, Harry A; Ramulu, Pradeep Y; Venkatesh, Rengaraj

2016-12-01

To compare anterior segment optical coherence tomography (ASOCT) angle morphology before and after laser peripheral iridotomy (LPI) in a cohort of South Indian subjects with primary angle-closure suspect (PACS) or primary angle-closure/primary angle-closure glaucoma (PAC/PACG) and to examine baseline parameters associated with angle widening. Prospective observational study. A total of 244 subjects aged ≥30 years with PACS or PAC/PACG in at least 1 eye. The ASOCT images and angle gonioscopic grades were analyzed for all subjects at baseline and 2 weeks after LPI. Multivariable linear and logistic regression models were used to determine predictors of angle widening (change in mean angle opening distance [AOD750]) and angle opening (all 4 quadrants with trabecular meshwork [TM] visible on gonioscopy after LPI). Change in ASOCT parameters with LPI and baseline predictors of angle widening. Laser peripheral iridotomy resulted in angle widening on ASOCT with significant increases in AOD750, angle recess area, and trabecular iris surface area (P < 0.05 for all). Gonioscopically, 44.7% of all subjects had open angles in all 4 quadrants after LPI, with a greater percentage of angles open in the PACS group compared with the PAC/PACG group (52.4% vs. 36.4%; P = 0.01). In multivariable regression analyses, greater postoperative angle widening as defined by change in AOD750 was associated with shorter baseline AOD750 and axial length, and greater baseline anterior chamber depth, iris curvature, and lens vault (P ≤ 0.002 for all). Gonioscopic angle opening after LPI was more common with wider baseline angle width (modified Shaffer grade) and lower cup-to-disc ratio (P < 0.001 for both). In a South Indian population with PACS or PAC/PACG, LPI results in significant anterior chamber angle widening seen on both ASOCT and gonioscopy, although some degree of persistent iridotrabecular contact was present in approximately half of PACS eyes and approximately two thirds of PAC/PACG eyes on gonioscopy. The greatest widening by ASOCT was observed in eyes with features most consistent with greater baseline pupillary block. Copyright © 2016 American Academy of Ophthalmology. All rights reserved.

Optic disc size and other parameters from optical coherence tomography in Vietnamese-Americans.

PubMed

Peng, Pai-Huei; Fu, Sheena; Nguyen, Ngoc; Porco, Travis; Lin, Shan C

2011-08-01

To investigate the optic disc parameters by optical coherence tomography (OCT) in Vietnamese with various types of glaucoma. Medical charts of Vietnamese and White patients within a single practice were reviewed. Disc and rim areas by OCT were compared among nonglaucoma controls, different types of glaucoma, and glaucoma suspect. The association of these parameters with demographic and ocular features was evaluated. Data from 1416 Vietnamese and 57 White patients were included. A larger mean disc area was observed in eyes with primary angle-closure glaucoma than in eyes with primary angle-closure and primary angle-closure suspect (both P<0.001). There was no association between disc size with central corneal thickness (P=0.051) and sex (P=0.155). Vietnamese patients with glaucoma and glaucoma suspicion had larger discs than diagnosis-matched Whites (P=0.043 and 0.021, respectively). Vietnamese patients with glaucoma seem to have larger optic discs than White patients. Central corneal thickness had no association with disc area in this study population.

Segmentation and Quantification for Angle-Closure Glaucoma Assessment in Anterior Segment OCT.

PubMed

Fu, Huazhu; Xu, Yanwu; Lin, Stephen; Zhang, Xiaoqin; Wong, Damon Wing Kee; Liu, Jiang; Frangi, Alejandro F; Baskaran, Mani; Aung, Tin

2017-09-01

Angle-closure glaucoma is a major cause of irreversible visual impairment and can be identified by measuring the anterior chamber angle (ACA) of the eye. The ACA can be viewed clearly through anterior segment optical coherence tomography (AS-OCT), but the imaging characteristics and the shapes and locations of major ocular structures can vary significantly among different AS-OCT modalities, thus complicating image analysis. To address this problem, we propose a data-driven approach for automatic AS-OCT structure segmentation, measurement, and screening. Our technique first estimates initial markers in the eye through label transfer from a hand-labeled exemplar data set, whose images are collected over different patients and AS-OCT modalities. These initial markers are then refined by using a graph-based smoothing method that is guided by AS-OCT structural information. These markers facilitate segmentation of major clinical structures, which are used to recover standard clinical parameters. These parameters can be used not only to support clinicians in making anatomical assessments, but also to serve as features for detecting anterior angle closure in automatic glaucoma screening algorithms. Experiments on Visante AS-OCT and Cirrus high-definition-OCT data sets demonstrate the effectiveness of our approach.

Changes in ocular biometry and anterior chamber parameters after pharmacologic mydriasis and peripheral iridotomy in primary angle closure suspects.

PubMed

Razeghinejad, Mohammad Reza; Lashkarizadeh, Hamid; Nowroozzadeh, Mohammad Hossein; Yazdanmehr, Mohammad

2016-01-01

The aim of this study was to evaluate the effects of pharmacologic mydriasis and Peripheral Iridotomy (PI) on ocular biometry and anterior chamber parameters in primary angle closure suspects. In this prospective interventional case series, 21 primary angle closure suspects were enrolled. Intraocular pressure, refraction, ocular biometry (Lenstar, LS900), and anterior chamber parameters (Pentacam HR) were measured at four occasions: before PI (before and after mydriasis with phenylephrine) and two weeks after PI (before and after mydriasis). The study was conducted on both eyes and only one eye per patient, in random, was included in the analysis. The mean age of the participants was 60±7 years and 17 (81%) were female. There were no significant differences in intraocular pressure, refraction, keratometry, biometric and anterior chamber parameters between groups, except for anterior chamber volume, which showed increments with PI and mydriasis. The corresponding values for anterior chamber volume were as follows: 88.2±13.7mm(3) before PI, undilated; 106.3±18.8 before PI, dilated; 99.0±14.6 after PI, undilated, and 107.4±16.5 after PI, dilated (P<0.001). This study showed no change in the ocular biometric and anterior chamber parameters including iridocorneal angle after PI and/or pharmacologic mydriasis except for increments in anterior chamber volume. This factor has the potential to be used as a numerical proxy for iris position in evaluating and monitoring patients with primary angle closure suspects after PI. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Comparison of circumferential peripheral angle closure using iridotrabecular contact index after laser iridotomy versus combined laser iridotomy and iridoplasty.

PubMed

Cho, Hyun-Kyung; Kee, Changwon; Yang, Heon; Huh, Hyoun Do; Kim, Su Jin; Park, Young Min; Park, Jong Moon

2017-11-01

To compare the quantitative changes of peripheral angle after laser iridotomy (LI) alone (group A) or combined LI and Iridoplasty (group B) using iridotrabecular contact (ITC) index by swept-source anterior segment optical coherence tomography (AS-OCT). In this prospective comparative observational study, OCT images were obtained before and after the procedure. In each image frame, scleral spur (SS) and the ITC end point (EP) were marked and ITC index was calculated as a percentage of the angle closure from 360°. Age, gender, diagnosis and initial ITC index in Group B were matched with group A. Changes in ITC index, anterior chamber angle parameters, and intraocular pressure (IOP) were inspected. Thirty-three eyes (20 patients) with shallow anterior chamber were included in each group. Initial ITC index and initial IOP were not significantly different between the two groups (both p > 0.05). However, ITC index and IOP after the procedure were significantly lower in group B than those in group A (ITC index: 31.3 ± 23.2 in group A, 19.0 ± 21.3 in group B, p = 0.011, IOP: p = 0.004). All anterior chamber angle parameters in group B and all parameters in group A except nasal trabecular-iris angles (TIA) were significantly increased after the laser procedure (all p < 0.05). In patients with shallow anterior chamber, combined LI and Iridoplasty may open the peripheral angle better than LI alone. Iridoplasty may be able to additionally relieve the peripheral angle closure caused by other mechanisms than pupillary block. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

[Resistance to pressure of bronchial closures. Comparison of pressure resistance of manual and stapler bronchial closures depending on the angle to the cartilaginous rings].

PubMed

Ludwig, C; Behrend, M; Hoffarth, U; Schüttler, W; Stoelben, E

2004-09-01

This study was aimed to determine the resistance to pressure of manual and stapled bronchial closures under ideal conditions (90 degrees to the bronchial tree) and parallel to the trachea (45 degrees). An experimental study was done on 60 explanted pig tracheae which were alternatively closed with either double-layer, running sutures angled 90 degrees to the cartilaginous rings or an automatic stapling device. The closure line was placed exactly 90 degrees to the bronchial tree in 30 cases and parallel to the trachea (45 degrees) in 30. The sutures were placed under pressure until air leakage was observed. The leakage pressure was digitally recorded. A statistically significant difference existed between the two groups. Mechanical sutures proved more resistant to pressure (P=0.011). Under ideal conditions, the resistance to pressure of mechanical sutures is equal to if not better than that of manual sutures.

Longitudinal Changes of Angle Configuration in Primary Angle-Closure Suspects

PubMed Central

Jiang, Yuzhen; Chang, Dolly S.; Zhu, Haogang; Khawaja, Anthony P.; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M.

2015-01-01

Objective To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Design Longitudinal cohort study. Participants Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Methods Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Main Outcome Measures Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. Results No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8–1.6) in treated eyes and 1.6°/year (95% CI, 1.3–2.0) in untreated eyes (P<0.001). Conclusions Angle width of treated eyes increased markedly after LPI, remained stable for 6 months, and then decreased significantly by 18 months after LPI. Untreated eyes experienced a more consistent and rapid decrease in angle width over the same time period. PMID:24835757

Biometric Differences between Unilateral Chronic Primary Angle Closure Glaucoma and Fellow Non-Glaucomatous Eyes.

PubMed

Wang, Wei; Li, Xinyi; Chen, Shida; Huang, Wenbin; Zhang, Xiulan

2017-11-29

To compare biometric differences between eyes with unilateral chronic primary angle-closure glaucoma (PACG) and fellow non-glaucomatous eyes in the same patient. Clinical data and imaging records of 17 patients with unilateral PACG were retrospectively reviewed. The fellow eyes with primary angle-closure (PAC) or primary angle-closure suspected (PACS) were grouped in Group 1. The PACG eyes were set as Group 2. The biometric parameters of both eyes were measured by IOL-Master, anterior segment optical coherence tomography (AS-OCT), and swept source OCT. The iris area in Group 1 was significantly thicker than that in Group 2 (1.590 ± 0.267 versus 1.365 ± 0.352, P = 0.016). Choroidal thickness in the macular region was thicker in Group 1 than in Group 2, with statistical significance at inner temporal grid (282.7 ± 121.1 versus 191.6 ± 90.3, P = 0.036), central field (297.4 ± 130.6 versus 200.1 ± 96.3, P = 0.029), inner nasal grid (283.1 ± 128.3 versus 194.8 ± 91.8, P = 0.040), and average value (265.3 ± 105.6 versus 191.1 ± 87.0, P = 0.049). Group 1 also had thicker peripapillary choroidal thickness at 1 o'clock (141.4 ± 68.4 versus 101.8 ± 39.0, P = 0.025) and 12 o'clock (141.5 ± 82.3 versus 104.5 ± 44.6, P = 0.037) compared to Group 2. The multivariate logistic regression analyses showed that only intraocular pressure was independently associated with PACG and explained 58.3% variance of PACG. In unilateral PACG, there was significant inter-eye difference in anterior and posterior segment parameters. Longitudinal comparisons are required to further understand the differences in pathology of angle closures.

Meta-analysis of the Efficacy and Safety of Latanoprost Monotherapy in Patients With Angle-closure Glaucoma.

PubMed

Chen, Ru; Yang, Ke; Zheng, Zhong; Ong, Moh-Lim; Wang, Ning-Li; Zhan, Si-Yan

2016-03-01

To systematically evaluate the safety and efficacy of latanoprost monotherapy for the treatment of patients with angle-closure glaucoma. We searched EMBASE, Medline, Cochrane Library, Chinese Journal Full-text Database (CNKI), Chinese Science and Technology Periodical Database (VIP), and Wang Fang using the search terms "latanoprost" (or its commercial name, Xalatan) and "angle-closure glaucoma." Resulting articles were then screened using preset inclusion criteria. Subgroup and sensitivity analyses were performed to evaluate the impact of research population, research type (blinded or controlled), and withdrawal/loss to follow-up. A total of 17 studies (n=807) were included in this meta-analysis. The primary outcome measure was intraocular pressure (IOP). Changes in the mean, peak, and trough IOP from baseline were used as effect measures. As I statistic revealed statistical heterogeneity, the random-effects model was applied. With the exception of 2 non-Asian populations from Australia and Peru, all 13 countries included in this study were from Asia. Latanoprost reduced mean IOP by 7.9 mm Hg (32.4%), peak IOP by 7.4 mm Hg (29.8%), and trough IOP by 7.9 mm Hg (32.5%). The most frequent ocular adverse effects were ocular hyperemia, discomfort (including eye irritation, ocular discomfort, foreign body sensation, and itching), and blurred vision with a total incidence rate of 9.4%, 8.7%, and 5.2%, respectively. Systemic adverse effects encompass rhinitis, dizziness, headache, and nonspecific skin pigmentation. Latanoprost is effective at reducing the IOP of patients with angle-closure glaucoma. Adverse reactions associated with latanoprost were mainly ocular in nature.

An uncommon case of intermittent Pourfour du Petit Syndrome associated with acute angle-closure glaucoma successfully treated by laser iridotomy.

PubMed

Farci, Roberta; Napoli, Pietro Emanuele; Fossarello, Maurizio

2017-07-03

To describe a case of acute angle-closure glaucoma secondary to intermittent mydriasis related to Pourfour du Petit Syndrome caused by tracheal deviation. A 70-year-old Caucasian woman visited the Emergency Room of the University Eye Clinic complaining of blurring of vision and difficulty to move superior eyelid in her right eye. Examination revealed reactive mydriasis, and upper lid retraction on the right side. The rest of the ophthalmological examination was normal, and a cranial computed tomography (CT) did not identify any abnormalities. A cervical CT showed the presence of an accentuated lateral right convex deviation of the trachea, attributable to a fibrothorax. A right Pourfour du Petit syndrome was suspected. Although the mydriasis had in the meantime vanished, the patient was admitted to the Neurological Clinic. Five days later she suffered acute pain in her right eye. Ophthalmological examination of the right eye revealed conjunctival hyperemia, marked corneal edema, reduced depth of anterior chamber, permanent mydriasis. As assessed by Goldmann applanation tonometry, intraocular pressure (IOP) was 48 mm Hg. Fundus examination was normal in both eyes. Gonioscopy revealed angle closure in all quadrants. Slit lamp examination of the contralateral eye was normal; IOP was 10 mm Hg. After hypotensive medical therapy, iridotomy with YAG laser was performed. Thereafter, IOP stabilized at 12 mm Hg. This is the first report in the literature of a case of acute angle-closure glaucoma secondary to mydriasis related to Pourfour du Petit Syndrome caused by tracheal deviation.

Solid motor aft closure insulation erosion. [heat flux correlation for rate analysis

NASA Technical Reports Server (NTRS)

Stampfl, E.; Landsbaum, E. M.

1973-01-01

The erosion rate of aft closure insulation in a number of large solid propellant motors was empirically analyzed by correlating the average ablation rate with a number of variables that had previously been demonstrated to affect heat flux. The main correlating parameter was a heat flux based on the simplified Bartz heat transfer coefficient corrected for two-dimensional effects. A multiplying group contained terms related to port-to-throat ratio, local wall angle, grain geometry and nozzle cant angle. The resulting equation gave a good correlation and is a useful design tool.

Evaluation of blotchy pigments in the anterior chamber angle as a sign of angle closure

PubMed Central

Rao, Harsha L; Mungale, Sachin C; Kumbar, Tukaram; Parikh, Rajul S; Garudadri, Chandra S

2012-01-01

Background: Blotchy pigments in the anterior chamber (AC) angle are considered diagnostic of primary angle closure (PAC). But there are no reports either on the prevalence of blotchy pigments in AC angles or the validity of this sign. Aims: To determine the prevalence of blotchy pigments in AC angles and to evaluate their relationship with glaucomatous optic neuropathy (GON) in eyes with occludable angles. Setting and Design: Cross-sectional, comparative study. Materials and Methods: Gonioscopy was performed in 1001 eyes of 526 subjects (245 eyes of 148 consecutive, occludable angle subjects and 756 eyes of 378 non-consecutive, open angle subjects), above 35 years of age. Quadrant-wise location of blotchy pigments was documented. Statistical Analysis: Odds of blotchy pigments in occludable angles against that in open angles were evaluated. Relationship of GON with blotchy pigments in occludable angle eyes was evaluated using a multivariate model. Results: Prevalence of blotchy pigments in occludable angles was 28.6% (95% CI, 22.9-34.3) and in open angles was 4.7% (95% CI, 3.2-6.3). Blotchy pigments were more frequently seen in inferior (16%) and superior quadrants (15%) of occludable angles, and inferior quadrant of open angles (4%). Odds of superior quadrant blotchy pigments in occludable angles were 33 times that in open angles. GON was seen in 107 occludable angle eyes. Blotchy pigments were not significantly associated with GON (odds ratio = 0.5; P = 0.1). Conclusions: Blotchy pigments were seen in 28.6% of occludable angle eyes and 4.7% of open angles eyes. Presence of blotchy pigments in the superior quadrant is more common in occludable angles. Presence of GON in occludable angle eyes was not associated with blotchy pigments. PMID:23202393

Functional and Structural Changes in a Canine Model of Hereditary Primary Angle-Closure Glaucoma

PubMed Central

Kecova, Helga; Harper, Matthew M.; Nilaweera, Wijitha; Kuehn, Markus H.; Kardon, Randy H.

2010-01-01

Purpose. To characterize functional and structural changes in a canine model of hereditary primary angle-closure glaucoma. Methods. Intraocular pressure (IOP) was evaluated with tonometry in a colony of glaucomatous dogs at 8, 15, 18, 20, and 30 months of age. Retinal function was evaluated using electroretinography (scotopic, photopic, and pattern). Examination of anterior segment structures was performed using gonioscopy and high-frequency ultrasonography (HFU). Results. A gradual rise in IOP was observed with an increase in age: 8 months, 14 mm Hg (median value); 15 months, 15.5 mm Hg; 18 months, 17.5 mm Hg; 20 months, 24 mm Hg; 30 months, 36 mm Hg. Provocative testing with mydriatic agents (tropicamide and atropine 1%) caused significant increases in IOP (35% and 50%, respectively). HFU analysis showed complete collapse of iridocorneal angles by 20 months of age. Scotopic and photopic ERG analysis did not reveal significant deficits, but pattern ERG analysis showed significantly reduced amplitudes in glaucomatous dogs (glaucoma, 3.5 ± 0.4 μV; control, 6.2 ± 0.3 μV; P = 0.004; Student's t-test). Histologic analysis revealed collapse of the iridocorneal angle, posterior bowing of the lamina cribrosa, swelling and loss of large retinal ganglion cells, increased glial reactivity, and increased thickening of the lamina cribrosa. Conclusions. Canine hereditary angle-closure glaucoma is characterized by a progressive increase in intraocular pressure, loss of optic nerve function, and retinal ganglion cell loss. PMID:19661222

[The prevalence of blindness caused by primary angle closure glaucoma in middle-aged Chinese population: a systematic review and meta-analysis].

PubMed

Liu, M L; Wang, Y X

2017-05-11

Objective: To evaluate the rate of blindness caused by primary angle closure glaucoma (PACG) in Chinese population of more than 40 years old, and to explore the effectiveness of a prevention and treatment system on PACG. Methods: We searched the databases of Pubmed, ScienceDirect, Springer Link, CNKI and Wanfang Data and collected all the original studies of the prevalence and blindness of angle closure glaucoma in China. The population was limited to over 40 years old. The research site was limited to the community-based, while the published time was not limited. Two researchers completed the literature search, data extraction and methodological quality assessment independently, with same criteria. Meta analysis was performed using R software. Results: Five papers were included in this study finally. A total of 26 437 cases of natural population over the age of 40 were observed, and 306 cases of angle closure glaucoma were found, of which 113 cases had binocular or monocular blindness caused by PACG. The random effect model meta-analysis results showed that the overall blindness rate was 38.3% [95% CI (28.1%, 49.6%)]. In Beijing, where the prevention and treatment system was well established, the blindness rate was far lower than that in the areas where the system was poorly established. Compared with the past, the blindness rate caused by PACG in Beijing decreased sharply. Conclusions: The rate of blindness caused by PACG is still high in the mainland of China. The prevention and treatment system is effective and worth promoting. (Chin J Ophthalmol, 2017, 53: 373 - 377) .

Evaluation of anterior chamber angle under dark and light conditions in angle closure glaucoma: An anterior segment OCT study.

PubMed

Masoodi, Habibeh; Jafarzadehpur, Ebrahim; Esmaeili, Alireza; Abolbashari, Fereshteh; Ahmadi Hosseini, Seyed Mahdi

2014-08-01

To evaluate changes of nasal and temporal anterior chamber angle (ACA) in subjects with angle closure glaucoma using Spectralis AS-OCT (SAS-OCT) under dark and light conditions. Based on dark-room gonioscopy, 24 subjects with open angles and 86 with narrow angles participated in this study. The nasal and temporal angle opening distance at 500 μm anterior to the scleral spur (AOD500), nasal and temporal ACA were measured using SAS-OCT in light and dark conditions. In 2 groups, ACA and AOD500 in nasal and temporal quadrants were significantly greater in light compared to dark (all with p=0.000). The AOD500 and ACA were significantly higher in nasal than temporal in measured conditions for 2 groups except the ACA and AOD500 of normal group measured in light. The difference between nasal and temporal in dark (29.07 ± 65.71 μm for AOD500 and 5.7 ± 4.07° for ACA) was greater than light (24.86 ± 79.85 μm for AOD500 and 2.09 ± 7.21° for ACA) condition. But the difference was only significant for ACA (p=0.000). The correlation analysis showed a negative correlation between AOD500 and pupil diameter in temporal and nasal quadrants (both with p=0.000). While temporal AOD500 difference correlated with spherical equivalent, temporal and asal gonioscopy, nasal AOD correlated with IOP, temporal and nasal gonioscopy. Clinically important changes in ACA structure could be detected with SAS-OCT in nasal and temporal quadrants under different illumination intensity. The results could help in improvement of examination condition for better and more accurate assessment of individuals with angle closure glaucoma. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Clinical and Anterior Segment Anatomical Features in Primary Angle Closure Subgroups Based on Configurations of Iris Root Insertion.

PubMed

Hong, Ji Wook; Yun, Sung-Cheol; Sung, Kyung Rim; Lee, Jong Eun

2016-06-01

To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT0, IT500, IT750, and IT1500), lens vault, iris area, angle opening distance (AOD500), angle recess area (ARA750), and trabecular iris space area (TISA750) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT0 (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm(2), p = 0.045), lower ARA750 (0.112 ± 0.08 vs. 0.154 ± 0.08 mm(2), p = 0.017) and AOD500 (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Corneal status in primary angle-closure glaucoma with a history of acute attack.

PubMed

Chen, Mei-Ju; Liu, Catherine Jui-Ling; Cheng, Ching-Yu; Lee, Shui-Mei

2012-01-01

The corneal status of patients with primary angle-closure glaucoma (PACG) with a history of acute attack was investigated. This cross-sectional study included 40 eyes of PACG patients with an earlier documented symptomatic acute angle-closure attack (aPACG), 40 uninvolved fellow eyes of aPACG patients (fPACG), 44 eyes of chronic PACG patients without such a history (cPACG), and 50 eyes of age-matched normal participants. All glaucoma patients had patent peripheral iridotomies with adequate intraocular pressure control. The examinations and recorded parameters included visual acuity, intraocular pressure, gonioscopy, vertical cup-to-disc ratio, specular microscopy, central corneal pachymetry, refraction, corneal curvature radius, anterior chamber depth, axial length, and lens thickness measurements, and the presenting intraocular pressure and the duration of acute angle-closure attack for aPACG eyes. The mean endothelial cell density was 2271±80 cells/mm(2) in aPACG, 2458±79 cells/mm(2) in fPACG, 2379±50 cells/mm(2) in cPACG, and 2559±45 cells/mm(2) in controls. The aPACG eyes had significantly lower endothelial cell density compared with normal eyes (P=0.002). There was no significant difference in endothelial cell density of aPACG eyes compared with fPACG or cPACG eyes. Multivariate analysis showed the duration of the acute attack was the only factor independently associated with corneal endothelial density of aPACG eyes. The mean central corneal thickness of aPACG (549±32 μm) did not differ significantly from control eyes (552±27 μm), cPACG (557±32 μm), and fPACG (553±31 μm) (P=0.911, 0.274, and 0.725, respectively). Corneal curvature radius of aPACG eyes was not significantly different from that of the comparison groups (all P>0.05). Corneal endothelial cell density was significantly reduced in aPACG eyes compared with normal eyes. No significant difference in endothelial cell density of aPACG eyes was noted when compared with fPACG or cPACG eyes. Corneal endothelial cell density was negatively associated with the duration of the acute attack, but was not associated with demographic and biometric characteristics. Central corneal thickness and corneal curvature radius were not associated with an earlier acute angle-closure attack.

Effect of laser peripheral iridotomy on anterior chamber angle anatomy in primary angle closure spectrum eyes

PubMed Central

Kansara, Seema; Blieden, Lauren S.; Chuang, Alice Z.; Baker, Laura A.; Bell, Nicholas P.; Mankiewicz, Kimberly A.; Feldman, Robert M.

2015-01-01

Purpose To evaluate the change in trabecular-iris circumference volume (TICV) after laser peripheral iridotomy (LPI) in primary angle closure (PAC) spectrum eyes Patients and Methods Forty-two chronic PAC spectrum eyes from 24 patients were enrolled. Eyes with anterior chamber abnormalities affecting angle measurement were excluded. Intraocular pressure, slit lamp exam, and gonioscopy were recorded at each visit. Anterior segment optical coherence tomography (ASOCT) with 3D mode angle analysis scans were taken with the CASIA SS-1000 (Tomey Corp., Nagoya, Japan) before and after LPI. Forty-two pre-LPI ASOCT scans and 34 post-LPI ASOCT scans were analyzed using the Anterior Chamber Analysis and Interpretation (ACAI, Houston, TX) software. A mixed-effect model analysis was used to compare the trabecular-iris space area (TISA) changes among 4 quadrants, as well as to identify potential factors affecting TICV. Results There was a significant increase in all average angle parameters after LPI (TISA500, TISA750, TICV500, and TICV750). The magnitude of change in TISA500 in the superior angle was significantly less than the other angles. The changes in TICV500 and TICV750 were not associated with any demographic or ocular characteristics. Conclusion TICV is a useful parameter to quantitatively measure the effectiveness of LPI in the treatment of eyes with PAC spectrum disease. PMID:26066504

Pseudo-gonio synechia: an artifact on two-mirror gonioscopy.

PubMed

Garudadri, Chandra Sekhar

2010-01-01

Gonioscopy is an important component of evaluation of any glaucoma patient. Goldmann two-mirror and Sussman or Zeiss four-mirror are the commonly used gonioscopes. Presence of synechia in the angle is diagnostic of angle closure disease in an occludable angle. A patient with pseudo-gonio synechia that disappeared on indentation gonioscopy with Sussman lens but persisted with manipulation gonioscopy with a Goldmann lens is reported.

Late glaucoma after interstitial keratitis.

PubMed

Grant, W M

1975-01-01

In a systematic study of 45 patients who had syphilitic interstitial keratitis early in life and, many years later, were discovered to have glaucoma, there was evidence of two different but equally common mechanisms. In one group of patients, a deep-chamber type of glaucoma was superimposed on old inflammatory changes, was characteristically refractory to medical treatment, but did well with filtering surgery. The other group of patients had reversible angle-closure glaucoma associated with anatomically small anterior segments, and typically responded well to iridectomy. The late, refractory, deep-chamber type of glaucoma may involve endothelialization and formation of glass membrane in the angle, as seen in one excised eye. Occurrence of the shallow-chamber, reversible angle-closure type of glaucoma after interstitial keratitis may be coincidental, since no other evidence supports the idea that small anterior segments might be particularly prevalent among patients who have had congenital syphilis or interstitial keratitis.

Pseudo-gonio synechia: An artifact on two-mirror gonioscopy

PubMed Central

Garudadri, Chandra Sekhar

2010-01-01

Gonioscopy is an important component of evaluation of any glaucoma patient. Goldmann two-mirror and Sussman or Zeiss four-mirror are the commonly used gonioscopes. Presence of synechia in the angle is diagnostic of angle closure disease in an occludable angle. A patient with pseudo-goniosynechia that disappeared on indentation gonioscopy with Sussman lens but persisted with manipulation gonioscopy with a Goldmann lens is reported. PMID:20029147

The Effects of Phacoemulsification and Intraocular Lens Implantation on Anatomical and Functional Parameters in Patients with Primary Angle Closure: A Prospective Study. (An American Ophthalmological Society Thesis).

PubMed

Traverso, Carlo Enrico; Cutolo, Carlo Alberto

2017-08-01

To investigate the clinical, anatomical, and patient-reported outcomes of phacoemulsification (PE) with intraocular lens implantation performed to treat primary angle closure (PAC) and primary angle-closure glaucoma (PACG). Patients were evaluated at baseline and at 6 months after PE. The examination included visual acuity, intraocular pressure (IOP), visual field, optic nerve head, endothelial cell count (ECC), aqueous depth, and ocular biometric parameters. Patient-reported visual function and health status were assessed. Coprimary outcome measures were IOP changes, angle widening, and patient-reported visual function; secondary outcome measures were visual acuity changes, use of IOP-lowering medications, and complications. Univariate and multivariate analyses were performed to determine the predictors of IOP change. Thirty-nine cases were identified, and postoperative data were analyzed for 59 eyes, 39 with PACG and 20 with PAC. Globally, PE resulted in a mean reduction in IOP of -6.33 mm Hg (95% CI, -8.64 to -4.01, P <.001). Aqueous depth and angle measurements improved ( P <.01), whereas ECC significantly decreased ( P <.001). Both corrected and uncorrected visual acuity improved ( P <.01). The EQ visual analog scale did not change ( P =.16), but VFQ-25 improved ( P <.01). The IOP-lowering effect of PE was greater in the PACG compared to the PAC group ( P =.04). In both groups, preoperative IOP was the most significant predictor of IOP change ( P <.01). No sight-threatening complications were recorded. Our data support the usefulness of PE in lowering the IOP in patients with PAC and PACG. Although PE resulted in several anatomical and patient-reported visual improvements, we observe that a marked decrease in ECC should be carefully weighed before surgery.

Appositional Closure Identified by Ultrasound Biomicroscopy in Population-Based Primary Angle-Closure Glaucoma Suspects: The Liwan Eye Study

PubMed Central

Kong, Xiangbin; Foster, Paul J.; Huang, Qunxiao; Zheng, Yingfeng; Huang, Wenyong; Cai, Xiaoyu

2011-01-01

Purpose. To describe the characteristics of the iridocorneal angle using ultrasound biomicroscopy (UBM) in Chinese people classified gonioscopically as having suspected primary angle-closure (PACS) glaucoma. Methods. PACS were defined as not having visible posterior (usually pigmented) trabecular meshwork in two or more quadrants examined by static gonioscopy. The PACS and 1 of 10 those who did not meet this criterion were identified from a population-based survey. Iridotrabecular meshwork contact (ITC) was identified and further classified into low and high, according to standard UBM images. Those with high ITC were further classified according the configuration of ITC: B-type, with contiguous ITC from the base of the angle, and S-type, with ITC localized to the region of Schwalbe's line. Results. ITC was identified in 78.6% of the superior, 40.2% of the nasal, 59.8% of the inferior, and 25.6% of the temporal quadrants in the PACS (n = 117). These proportions were 43.9%, 15.8%, 29.8%, and 14.0% in the controls (n = 57), respectively. About two thirds of the eyes with ITC were classified as high. In those with high ITC, the number with B- and S-type ITC was very similar. The proportions of any high ITCs increased substantially from 15.4% in those with Shaffer angle grade 4 and 45.0% in grade 3, to 71.0% in grade 2, 70.2% in grade 1, and 86.4% in grade 0. Conclusions. More ITC is identified on UBM imaging than by gonioscopy. Careful consideration should be given to the assessment modality regarded as the reference standard in defining anatomic risk factors for glaucomatous visual loss and the need for treatment. PMID:21357394

Methyl-sulfonyl-methane (MSM)-induced acute angle closure.

PubMed

Hwang, Jeremy C; Khine, Kay T; Lee, Jennifer C; Boyer, David S; Francis, Brian A

2015-01-01

To report the first case of presumed bilateral acute angle closure (AAC) secondary to ingestion of the dietary supplement, methyl-sulfonyl-methane (MSM). A 35-year-old woman presented with bilateral AAC 1 week after starting multiple dietary supplements, one of which contained MSM. Ultrasound biomicroscopy demonstrated bilateral anterior rotation of the iris-lens diaphragm, ciliary body edema, and choroidal effusion. Four days after discontinuation of the supplements, her angle closure and uveal effusion resolved, and her best-corrected vision recovered to 20/20 bilaterally. Sulfa-based drugs have been reported to cause AAC, choroidal effusion, and ciliary body edema. In our patient, the coincidence of bilateral AAC with choroidal and ciliary body effusion that began 1 week after starting dietary supplements was suspicious for drug-induced AAC. The dietary supplement Basic Detox Nutrients contains MSM, the only constituent in the patient's medication list with a sulfonyl moiety. Given the similarities in chemical structure and clinical presentation, we postulate that MSM induces AAC in a manner similar to mechanisms previously described for other sulfa-based drugs. As MSM continues to be used and studied for its anti-inflammatory and antioxidative properties, investigators and marketers will need to be cognizant of its potential to cause AAC and provide proper warning to consumers.

[Screening method for angle closure and angle closure glaucoma using scanning laser polarimeter GDxVCC and photodynamic gonioscopy in a darkened room. One-year outcomes of systematic peripheral iridotomy].

PubMed

Malek-Chehire, N; Renard, G; Dreyfus, J-F; Lebuisson, D A; Pierre-Kahn, V

2013-12-01

Angle closure glaucoma, a recognized major world health issue disproportionately affecting women and Asians, is not often considered in our European populations, normotensive subjects, myopic patients, or subjects with a deep anterior chamber. Early diagnosis is worthwhile, as laser peripheral iridotomy (LPI) is an effective one-step treatment of the causal mechanism. We have performed a retrospective study of patients who underwent an LPI, the indication for which was based on "photodynamic" gonioscopy in a darkened room showing iridotrabecular contact in darkness. Such photodynamic gonioscopy was motivated by the presence of even minute defects in the nerve fiber layer as seen on the GDxVCC or the presence of a Van Herick sign (narrow limbal anterior chamber depth). One hundred and three eyes of 103 patients underwent LPI and a minimum 1-year follow-up (mean follow-up almost 2 years). Mean age was 63.7±11.8 years, and women accounted for 63.1% of cases. The vast majority (78.6%) of patients had neither glaucoma nor ocular hypertension. There were 60.1% hyperopes and 39.9% myopes. Over half (57%) had a deep or a very deep anterior chamber. After LPI, there was immediate deepening of the limbal depth of the anterior chamber in 100% of cases. The aqueous humor that flowed forward was almost always viscous-looking. After 1 year, the IOP was 1.3mm Hg±2.4 lower (P<.001) (t test). All patients who had experienced morning headaches (44% of patients) were relieved of this symptom. GDxVCC after 1 year was clearly improved in 18% of cases, slightly improved in 20%, stable in 50%, slightly worse in 11% of cases, and clearly worse in 1%. Cases treated at an earlier stage had a better improvement in GDxVCC. Our study shows frequent chronic angle closure in our European population even with deep anterior chambers. Absence of a Van Herick sign does not rule out angle closure at night. A photodynamic gonioscopy with the Goldmann three-lens mirror (to avoid unintentional indentation with the small diameter lenses in these normotensive eyes) should be performed in a darkened room. LPI is an effective one-step treatment of the underlying cause, that is particularly beneficial if performed early. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Predicting Peri-Device Leakage of Left Atrial Appendage Device Closure Using Novel Three-Dimensional Geometric CT Analysis.

PubMed

Chung, Hyemoon; Jeon, Byunghwan; Chang, Hyuk-Jae; Han, Dongjin; Shim, Hackjoon; Cho, In Jeong; Shim, Chi Young; Hong, Geu-Ru; Kim, Jung-Sun; Jang, Yangsoo; Chung, Namsik

2015-12-01

After left atrial appendage (LAA) device closure, peri-device leakage into the LAA persists due to incomplete occlusion. We hypothesized that pre-procedural three-dimensional (3D) geometric analysis of the interatrial septum (IAS) and LAA orifice can predict this leakage. We investigated the predictive parameters of LAA device closure obtained from baseline cardiac computerized tomography (CT) using a novel 3D analysis system. We conducted a retrospective study of 22 patients who underwent LAA device closure. We defined peri-device leakage as the presence of a Doppler signal inside the LAA after device deployment (group 2, n = 5) compared with patients without peri-device leakage (group 1, n = 17). Conventional parameters were measured by cardiac CT. Angles θ and φ were defined between the IAS plane and the line, linking the LAA orifice center and foramen ovale. Group 2 exhibited significantly better left atrial (LA) function than group 1 (p = 0.031). Pre-procedural θ was also larger in this group (41.9° vs. 52.3°, p = 0.019). The LAA cauliflower-type morphology was more common in group 2. Overall, the patients' LA reserve significantly decreased after the procedure (21.7 mm(3) vs. 17.8 mm(3), p = 0.035). However, we observed no significant interval changes in pre- and post-procedural values of θ and φ in either group (all p > 0.05). Angles between the IAS and LAA orifice might be a novel anatomical parameter for predicting peri-device leakage after LAA device closure. In addition, 3D CT analysis of the LA and LAA orifice could be used to identify clinically favorable candidates for LAA device closure.

A new formulation of the dispersion tensor in homogeneous porous media

NASA Astrophysics Data System (ADS)

Valdés-Parada, Francisco J.; Lasseux, Didier; Bellet, Fabien

2016-04-01

Dispersion is the result of two mass transport processes, namely molecular diffusion, which is a pure mixing effect and hydrodynamic dispersion, which combines mixing and spreading. The identification of each contribution is crucial and is often misinterpreted. Traditionally, under a volume averaging framework, a single closure problem is solved and the resulting fields are substituted into diffusive and dispersive filters. However the diffusive filter (that leads to the effective diffusivity) allows passing information from convection, which leads to an incorrect definition of the effective medium coefficients composing the total dispersion tensor. In this work, we revisit the definitions of the effective diffusivity and hydrodynamic dispersion tensors using the method of volume averaging. Our analysis shows that, in the context of laminar flow with or without inertial effects, two closure problems need to be computed in order to correctly define the corresponding effective medium coefficients. The first closure problem is associated to momentum transport and needs to be solved for a prescribed Reynolds number and flow orientation. The second closure problem is related to mass transport and it is solved first with a zero Péclet number and second with the required Péclet number and flow orientation. All the closure problems are written using closure variables only as required by the upscaling method. The total dispersion tensor is shown to depend on the microstructure, macroscopic flow angles, the cell (or pore) Péclet number and the cell (or pore) Reynolds number. It is non-symmetric in the general case. The condition for quasi-symmetry is highlighted. The functionality of the longitudinal and transverse components of this tensor with the flow angle is investigated for a 2D model porous structure obtaining consistent results with previous studies.

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

PubMed Central

Congdon, N G; Foster, P J; Wamsley, S; Gutmark, J; Nolan, W; Seah, S K; Johnson, G J; Broman, A T

2002-01-01

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. PMID:11801496

What was Glaucoma Called Before the 20th Century?

PubMed Central

Leffler, Christopher T.; Schwartz, Stephen G.; Giliberti, Francesca M.; Young, Matthew T.; Bermudez, Dennis

2015-01-01

Glaucoma involves a characteristic optic neuropathy, often with elevated intraocular pressure. Before 1850, poor vision with a normal eye appearance, as occurs in primary open-angle glaucoma, was termed amaurosis, gutta serena, or black cataract. Few observers noted palpable hardness of the eye in amaurosis. On the other hand, angle-closure glaucoma can produce a green or gray pupil, and therefore was called, variously, glaucoma (derived from the Greek for glaucous, a nonspecific term connoting blue, green, or light gray) and viriditate oculi. Angle closure, with palpable hardness of the eye, mydriasis, and anterior prominence of the lens, was described in greater detail in the 18th and 19th centuries. The introduction of the ophthalmoscope in 1850 permitted the visualization of the excavated optic neuropathy in eyes with a normal or with a dilated greenish-gray pupil. Physicians developed a better appreciation of the role of intraocular pressure in both conditions, which became subsumed under the rubric “glaucoma”. PMID:26483611

Use of gonioscopy in medicare beneficiaries before glaucoma surgery.

PubMed

Coleman, Anne L; Yu, Fei; Evans, Stacy J

2006-12-01

The American Academy of Ophthalmology Preferred Practice Patterns for angle closure and open-angle glaucoma (OAG) patients recommends performing bilateral gonioscopy upon initial presentation to evaluate the possibility of narrow angle or angle-closure glaucoma (ACG) and then repeating the examination at least every 5 years. This study aims to assess how commonly eye care providers perform gonioscopy before planned glaucoma surgery in OAG, anatomic narrow angle, and ACG in the Medicare population. Data obtained from a 5% random sample of Medicare beneficiaries undergoing glaucoma surgery in the United States in 1999 were retrospectively reviewed. The proportion of patients with evidence of at least one gonioscopic examination before glaucoma surgery was determined for the period of 1995 to 1999. Demographic and clinical factors potentially influencing the decision to perform gonioscopy were also examined. Overall, gonioscopy is apparently performed in 49% of Medicare beneficiaries during the 4 to 5 years preceding glaucoma surgery. This rate was significantly lower (P < 0.001) in patients with OAG (46%), as compared with anatomic narrow angle (58%) and ACG (57%) patients. Hispanics, elderly (aged 70 to 84), patients undergoing laser iridotomy, and patients receiving care in the New York/New Jersey area all had significantly higher apparent preoperative gonioscopy rates (P < 0.05). Gonioscopy examination before glaucoma surgery in Medicare beneficiaries is underused, undercoded, and/or miscoded, given current recommendations. Underuse is of particular concern in patients undergoing laser iridotomy as it is the diagnostic test of choice in ACG.

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial.

PubMed

Azuara-Blanco, Augusto; Burr, Jennifer M; Cochran, Claire; Ramsay, Craig; Vale, Luke; Foster, Paul; Friedman, David; Quayyum, Zahidul; Lai, Jimmy; Nolan, Winnie; Aung, Tin; Chew, Paul; McPherson, Gladys; McDonald, Alison; Norrie, John

2011-05-23

Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. ISRCTN44464607.

Self-organized kilometer-scale shoreline sand wave generation: Sensitivity to model and physical parameters

NASA Astrophysics Data System (ADS)

Idier, Déborah; Falqués, Albert; Rohmer, Jérémy; Arriaga, Jaime

2017-09-01

The instability mechanisms for self-organized kilometer-scale shoreline sand waves have been extensively explored by modeling. However, while the assumed bathymetric perturbation associated with the sand wave controls the feedback between morphology and waves, its effect on the instability onset has not been explored. In addition, no systematic investigation of the effect of the physical parameters has been done yet. Using a linear stability model, we investigate the effect of wave conditions, cross-shore profile, closure depth, and two perturbation shapes (P1: cross-shore bathymetric profile shift, and P2: bed level perturbation linearly decreasing offshore). For a P1 perturbation, no instability occurs below an absolute critical angle θc0≈ 40-50°. For a P2 perturbation, there is no absolute critical angle: sand waves can develop also for low-angle waves. In fact, the bathymetric perturbation shape plays a key role in low-angle wave instability: such instability only develops if the curvature of the depth contours offshore the breaking zone is larger than the shoreline one. This can occur for the P2 perturbation but not for P1. The analysis of bathymetric data suggests that both curvature configurations could exist in nature. For both perturbation types, large wave angle, small wave period, and large closure depth strongly favor instability. The cross-shore profile has almost no effect with a P1 perturbation, whereas large surf zone slope and gently sloping shoreface strongly enhance instability under low-angle waves for a P2 perturbation. Finally, predictive statistical models are set up to identify sites prone to exhibit either a critical angle close to θc0 or low-angle wave instability.

Novel Automated Approach to Predict the Outcome of Laser Peripheral Iridotomy for Primary Angle Closure Suspect Eyes Using Anterior Segment Optical Coherence Tomography.

PubMed

Koh, Victor; Swamidoss, Issac Niwas; Aquino, Maria Cecilia D; Chew, Paul T; Sng, Chelvin

2018-04-27

Develop an algorithm to predict the success of laser peripheral iridotomy (LPI) in primary angle closure suspect (PACS), using pre-treatment anterior segment optical coherence tomography (ASOCT) scans. A total of 116 eyes with PACS underwent LPI and time-domain ASOCT scans (temporal and nasal cuts) were performed before and 1 month after LPI. All the post-treatment scans were classified to one of the following categories: (a) both angles open, (b) one of two angles open and (c) both angles closed. After LPI, success is defined as one or more angles changed from close to open. In this proposed method, the pre and post-LPI ASOCT scans were registered at the corresponding angles based on similarities between the respective local descriptor features and random sample consensus technique was used to identify the largest consensus set of correspondences between the pre and post-LPI ASOCT scans. Subsequently, features such as correlation co-efficient (CC) and structural similarity index (SSIM) were extracted and correlated with the success of LPI. We included 116 eyes and 91 (78.44%) eyes fulfilled the criteria for success after LPI. Using the CC and SSIM index scores from this training set of ASOCT images, our algorithm showed that the success of LPI in eyes with narrow angles can be predicted with 89.7% accuracy, specificity of 95.2% and sensitivity of 36.4% based on pre-LPI ASOCT scans only. Using pre-LPI ASOCT scans, our proposed algorithm showed good accuracy in predicting the success of LPI for PACS eyes. This fully-automated algorithm could aid decision making in offering LPI as a prophylactic treatment for PACS.

Combined Wave and Current Bottom Boundary Layers: A Review

DTIC Science & Technology

2016-03-01

18 3.2 Wave and currents at arbitrary angles ....................................................................... 19 3.3 Eddy viscosity ...closure ................................................................................................. 22 3.3.1 Eddy viscosity for stratified fluids...23 3.3.2 Time-dependent eddy viscosities

Angle-closure glaucoma in an urban population in southern India. The Andhra Pradesh eye disease study.

PubMed

Dandona, L; Dandona, R; Mandal, P; Srinivas, M; John, R K; McCarty, C A; Rao, G N

2000-09-01

To assess the prevalence and features of angle-closure glaucoma (ACG) in an urban population in southern India. A population-based, cross-sectional study. A total of 2522 (85.4% of those eligible) persons of all ages, including 1399 persons 30 years of age or older, from 24 clusters representative of the population of Hyderabad city. The participants underwent an interview and detailed eye examination that included logarithm of minimum angle of resolution visual acuity, refraction, slit-lamp biomicroscopy, applanation tonometry, and gonioscopy; pupil dilatation and stereoscopic fundus evaluation was performed if the risk of angle-closure as a result of dilatation was not believed to be imminent. Humphrey threshold 24-2 visual fields (Humphrey Instruments Inc., San Leandro, CA) were performed when indicated by standardized criteria for disc damage or if intraocular pressure (IOP) was 22 mmHg or more. An occludable angle was defined as pigmented posterior trabecular meshwork not visible by gonioscopy in three quarters or more of the angle circumference. Manifest primary angle-closure glaucoma (PACG) was defined as IOP of 22 mmHg or more or glaucomatous optic disc damage with visual field loss in the presence of an occludable angle. An IOP of 22 mmHg or more or glaucomatous optic disc damage in the presence of an occludable angle secondary to an obvious cause was defined as secondary ACG. Manifest PACG and occludable angles without ACG were present in 12 and 24 participants, respectively, with age- and gender-adjusted prevalence (95% confidence interval [CI]) of 0.71% (0.34%-1.31%) and 1.41% (0.73%-2.09%) in participants 30 years of age or older, and 1.08% (0.36%-1.80%) and 2.21% (1.15%-3.27%) in participants 40 years of age or older, respectively. With multivariate analysis, the prevalence of these two conditions considered together increased significantly with age (P < 0.001); although not statistically significant, these were more common in females (odds ratio 1.70; 95% CI, 0.82-3.54) and in those belonging to lower socioeconomic strata as compared with middle and upper strata (odds ratio, 1.82; 95% CI, 0.88-3.74). The odds of manifest PACG were higher in the presence of hyperopia of more than 2 diopters ([D]; odds ratio, 3.69; 95% CI, 0.89-15.2). Only four of 12 participants (33.3%) with manifest PACG had been previously diagnosed, and one of 12 (8.3%) had peripheral iridotomy performed previously. Manifest PACG had caused blindness in one or both eyes in five of these 12 participants (41.7%); best-corrected distance visual acuity less than 20/400 in one or both eyes in four patients, and acuity less than 20/200 in one eye in another patient. Most (83.3%) of those with manifest PACG could be classified as having chronic form of the disease. We may have underestimated manifest PACG because visual fields were per- formed only on those with clinical suspicion of optic disc damage. Secondary ACG was present in two participants. The prevalence of PACG in this urban population in southern India is close to that reported recently in a Mongolian population. A large proportion of the PACG in this population was undiagnosed and untreated. Because visual loss resulting from PACG is potentially preventable if peripheral iridotomy or iridectomy is performed in the early stage, strategies for early detection of PACG could reduce the high risk of blindness resulting from PACG seen in this urban population in India.

Differences in iris thickness among African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans.

PubMed

Lee, Roland Y; Huang, Guofu; Porco, Travis C; Chen, Yi-Chun; He, Mingguang; Lin, Shan C

2013-12-01

To evaluate the capability of iris thickness parameters to explain the difference in primary angle-closure glaucoma prevalence among the different racial groups. In this prospective study, 436 patients with open and narrow angles that met inclusion criteria were consecutively recruited from the UCSF general ophthalmology and glaucoma clinics to receive anterior segment optical coherence tomography imaging under standardized dark conditions. Images from 11 patients were removed due to poor visibility of the scleral spurs and the remaining images were analyzed using the Zhongshan Angle Assessment Program to assess the following measurements for the nasal and temporal angle of the anterior chamber: iris thickness at 750 and 2000 μm from the scleral spurs and the maximum iris thickness at middle one third of the iris. Iris thickness parameters were compared among and within the following 5 different racial groups: African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans. In comparing iris parameters among the open-angle racial groups, significant differences were found for nasal iris thickness at 750 and 2000 μm from the scleral spurs in which Chinese Americans displayed the highest mean value (P=0.01, P<0.0001). Among the narrow-angle racial groups, significant difference was found for nasal iris thickness at 2000 μm from the scleral in which Chinese Americans showed the highest mean value (P<0.0001). Significant difference was also found for temporal maximum iris thickness at middle one third of the iris in which African Americans exhibited the highest mean value (P=0.021). Iris thickness was modeled as a function of angle status using linear mixed-effects regression, adjusting for age, sex, pupil diameter, spherical equivalent, ethnicity, and the use of both eyes in patients. The iris thickness difference between the narrow-angle and open-angle groups was significant (P=0.0007). Racial groups that historically showed higher prevalence of primary angle-closure glaucoma possess thicker irides.

The Frequency of Optical Coherence Tomography Testing in Glaucoma at a Single Academic Medical Center.

PubMed

Griffith, Joseph F; Goldberg, Jeffrey L

2016-03-01

To determine the frequency of optical coherence tomography (OCT) examinations compared with clinical examinations and visual field (VF) tests in patients with 5 types of glaucoma. A retrospective, longitudinal cohort study was conducted of 5154 patients treated between 2003 and 2010 at a single academic medical center. Patients were classified using billing records as having primary open-angle glaucoma, low-tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic angle-closure glaucoma, or pseudoexfoliation glaucoma. Analysis of variance, χ test, and exact χ test were performed to identify associations between glaucoma type and test frequency. Pigmentary open-angle glaucoma and NTG patients had a higher rate of undergoing at least 2 VFs (94.4%, 94.9%), and chronic angle-closure glaucoma patients had a lower rate of undergoing at least 2 OCTs (25.3%) than all other glaucoma types. NTG patients also had the highest rate of undergoing at least 2 OCTs and at least 2 VFs (36.6%). Overall, the rate of clinical examinations (2.68 examinations/y) exceeded the rates of OCTs (1.39 examinations/y), which exceeded the rate of VF tests (1.24 tests/y). There were no differences in OCT frequency between glaucoma types (0.91 to 1.63 OCTs/y). Within each glaucoma diagnosis, patients had clinical examinations more frequently than OCTs and clinical examinations more frequently than VFs. Primary open-angle glaucoma and pseudoexfoliation glaucoma patients also had OCTs more frequently than VFs. More patients had at least 2 VF tests than at least 2 OCTs (4481 vs. 1679). The relative use of clinical examinations, VF testing, and OCT imaging varies among glaucoma diagnoses.

Automatic anterior chamber angle assessment for HD-OCT images.

PubMed

Tian, Jing; Marziliano, Pina; Baskaran, Mani; Wong, Hong-Tym; Aung, Tin

2011-11-01

Angle-closure glaucoma is a major blinding eye disease and could be detected by measuring the anterior chamber angle in the human eyes. High-definition OCT (Cirrus HD-OCT) is an emerging noninvasive, high-speed, and high-resolution imaging modality for the anterior segment of the eye. Here, we propose a novel algorithm which automatically detects a new landmark, Schwalbe's line, and measures the anterior chamber angle in the HD-OCT images. The distortion caused by refraction is corrected by dewarping the HD-OCT images, and three biometric measurements are defined to quantitatively assess the anterior chamber angle. The proposed algorithm was tested on 40 HD-OCT images of the eye and provided accurate measurements in about 1 second.

Fractured Anterior Chamber Intraocular Lens (ACIOL) Complicating Nd: YAG Laser for Peripheral Iridotomy.

PubMed

Farah, Edgard; Koutsandrea, Chryssanthi; Papaefthimiou, Ioannis; Papaconstantinou, Dimitris; Georgalas, Ilias

2013-01-01

Laser peripheral iridotomy is the procedure of choice for the treatment of angle-closure glaucoma caused by relative or absolute pupillary block. Nd: YAG laser iridotomy has been reported to have several complications such as Iris bleeding, hyphema, transient IOP elevation, intraocular inflammation, choroidal, retinal detachment and vitreous hemorrhage. We report a case of a 74 year old lady on anticoagulant treatment who developed pupillary block and angle closure glaucoma after cataract surgery and anterior chamber intraocular lens (ACIOL) insertion complicated with intraoperative bleeding. The patient was treated with Nd: YAG laser iridotomy , however, the ACIOL was inadvertently fractured after a single shot of laser and it had to be replaced. Although the incidence is rare. Ophthalmologists and Opticians should be aware that an ACIOL may be fractured even after a single Nd:YAG laser shot and avoid to perform it close to the ACIOL. Pretreatment counseling should include this rare complication.

Genome-wide association analyses identify three new susceptibility loci for primary angle closure glaucoma

PubMed Central

Nongpiur, Monisha E; George, Ronnie; Chen, Li-Jia; Do, Tan; Abu-Amero, Khaled; Huang, Chor Kai; Low, Sancy; Tajudin, Liza-Sharmini A; Perera, Shamira A; Cheng, Ching-Yu; Xu, Liang; Jia, Hongyan; Ho, Ching-Lin; Sim, Kar Seng; Wu, Ren-Yi; Tham, Clement C Y; Chew, Paul T K; Su, Daniel H; Oen, Francis T; Sarangapani, Sripriya; Soumittra, Nagaswamy; Osman, Essam A; Wong, Hon-Tym; Tang, Guangxian; Fan, Sujie; Meng, Hailin; Huong, Dao T L; Wang, Hua; Feng, Bo; Baskaran, Mani; Shantha, Balekudaru; Ramprasad, Vedam L; Kumaramanickavel, Govindasamy; Iyengar, Sudha K; How, Alicia C; Lee, Kelvin Y; Sivakumaran, Theru A; Yong, Victor H K; Ting, Serena M L; Li, Yang; Wang, Ya-Xing; Tay, Wan-Ting; Sim, Xueling; Lavanya, Raghavan; Cornes, Belinda K; Zheng, Ying-Feng; Wong, Tina T; Loon, Seng-Chee; Yong, Vernon K Y; Waseem, Naushin; Yaakub, Azhany; Chia, Kee-Seng; Allingham, R Rand; Hauser, Michael A; Lam, Dennis S C; Hibberd, Martin L; Bhattacharya, Shomi S; Zhang, Mingzhi; Teo, Yik Ying; Tan, Donald T; Jonas, Jost B; Tai, E-Shyong; Saw, Seang-Mei; Hon, Do Nhu; Al-Obeidan, Saleh A; Liu, Jianjun; Chau, Tran Nguyen Bich; Simmons, Cameron P; Bei, Jin-Xin; Zeng, Yi-Xin; Foster, Paul J; Vijaya, Lingam; Wong, Tien-Yin; Pang, Chi-Pui

2014-01-01

Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. We conducted a genome-wide association study including 1,854 PACG cases and 9,608 controls across 5 sample collections in Asia. Replication experiments were conducted in 1,917 PACG cases and 8,943 controls collected from a further 6 sample collections. We report significant associations at three new loci: rs11024102 in PLEKHA7 (per-allele odds ratio (OR) = 1.22; P = 5.33 × 10−12), rs3753841 in COL11A1 (per-allele OR = 1.20; P = 9.22 × 10−10) and rs1015213 located between PCMTD1 and ST18 on chromosome 8q (per-allele OR = 1.50; P = 3.29 × 10−9). Our findings, accumulated across these independent worldwide collections, suggest possible mechanisms explaining the pathogenesis of PACG. PMID:22922875

The qualitative scoring MMSE pentagon test (QSPT): a new method for differentiating dementia with Lewy Body from Alzheimer's disease.

PubMed

Caffarra, Paolo; Gardini, Simona; Dieci, Francesca; Copelli, Sandra; Maset, Laura; Concari, Letizia; Farina, Elisabetta; Grossi, Enzo

2013-01-01

The differential diagnosis across different variants of degenerative diseases is sometimes controversial. This study aimed to validate a qualitative scoring method for the pentagons copy test (QSPT) of Mini-Mental State Examination (MMSE) based on the assessment of different parameters of the pentagons drawing, such as number of angles, distance/intersection, closure/opening, rotation, closing-in, and to verify its efficacy to differentiate dementia with Lewy Body (DLB) from Alzheimer's disease (AD). We established the reliability of the qualitative scoring method through the inter-raters and intra-subjects analysis. QSPT was then applied to forty-six AD and forty-six DLB patients, using two phases statistical approach, standard and artificial neural network respectively. DLB patients had significant lower total score in the copy of pentagons and number of angles, distance/intersection, closure/opening, rotation compared to AD. However the logistic regression did not allow to establish any suitable modeling, whereas using Auto-Contractive Map (Auto-CM) the DLB was more strongly associated with low scores in some qualitative parameters of pentagon copying, i.e. number of angles and opening/closure and, for the remaining subitems of the MMSE, in naming, repetition and written comprehension, and for demographic variables of gender (male) and education (6-13 years). Twist system modeling showed that the QSPT had a good sensitivity (70.29%) and specificity (78.67%) (ROC-AUC 0.74). The proposed qualitative method of assessment of pentagons copying used in combination with non-linear analysis, showed to be consistent and effective in the differential diagnosis between Lewy Body and Alzheimer's dementia.

Outcomes following acute primary angle closure in an Asian population.

PubMed

Tan, Anna M; Loon, Seng C; Chew, Paul T K

2009-07-01

Data regarding development of primary angle closure glaucoma (PACG) following acute primary angle closure (APAC) is conflicting. This study looks at outcomes after an APAC episode with a secondary aim to identify any risk factors that could predict progression to PACG. This is a retrospective review of the charts of consecutive patients who were diagnosed with APAC from December 2003 to June 2006. All were treated in a standard manner with initial intensive medical therapy or laser iridoplasty followed by early laser peripheral iridotomy within 24 h of presentation. Forty-two eyes of 41 patients were analysed. The mean follow-up period was 27.3 +/- 16.2 months. Nine eyes (21.4%) developed an increase in intraocular pressure (IOP) within a mean of 11.9 months (median 5 months) after resolution of APAC. Eight eyes went on to have trabeculectomy or glaucoma drainage device. At final follow up, the mean IOP of attack eye was 13.3 +/- 2.92 mmHg. None of the eyes, including those that underwent surgery, required topical medication to control IOP. Thirty-eight eyes (90.5%) have BCVA of 6/6 to 6/12. The duration of symptoms before presentation (P = 0.00) and duration taken to abort the acute attack (P = 0.01) were found to be significantly associated with development of PACG. The results of this study suggest that outcomes following successful treatment of APAC may not be as poor as described previously. Early aggressive management of the acute episode may have a role to play in preventing development of PACG after APAC.

Angle imaging: Advances and challenges

PubMed Central

Quek, Desmond T L; Nongpiur, Monisha E; Perera, Shamira A; Aung, Tin

2011-01-01

Primary angle closure glaucoma (PACG) is a major form of glaucoma in large populous countries in East and South Asia. The high visual morbidity from PACG is related to the destructive nature of the asymptomatic form of the disease. Early detection of anatomically narrow angles is important and the subsequent prevention of visual loss from PACG depends on an accurate assessment of the anterior chamber angle (ACA). This review paper discusses the advantages and limitations of newer ACA imaging technologies, namely ultrasound biomicroscopy, Scheimpflug photography, anterior segment optical coherence tomography and EyeCam, highlighting the current clinical evidence comparing these devices with each other and with clinical dynamic indentation gonioscopy, the current reference standard. PMID:21150037

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial

PubMed Central

2011-01-01

Background Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care. EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. Methods/Design EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible. The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events. A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. Trial Registration: ISRCTN44464607. PMID:21605352

Early intraocular pressure change after peripheral iridotomy with ultralow fluence pattern scanning laser and Nd:YAG laser in primary angle-closure suspect: Kowloon East Pattern Scanning Laser Study Report No. 3.

PubMed

Chan, Jeffrey Chi Wang; Choy, Bonnie Nga Kwan; Chan, Orlando Chia Chieh; Li, Kenneth Kai Wang

2018-02-01

Our purpose was to assess the early intraocular pressure (IOP) changes of ultralow fluence laser iridotomy using pattern scanning laser followed by neodymium:yttrium-aluminum-gamet (Nd:YAG) laser. This is a prospective interventional study. Thirty-three eyes of 33 adult Chinese primary angle-closure suspect subjects were recruited for prophylactic laser peripheral iridotomy. Sequential laser peripheral iridotomy was performed using pattern scanning laser followed by Nd:YAG laser. Visual acuity (VA) and IOP were measured before treatment, at 1 h, 1 day, 1 week, 1 month, 3 months and 6 months after laser. Laser energy used and complications were documented. Corneal endothelial cell count was examined at baseline and 6 months. Patency of the iridotomy was assessed at each follow-up visit. All subjects achieved patent iridotomy in a single session. The mean energy used was 0.335+/-0.088 J for the pattern scanning laser, and 4.767+/-5.780 mJ for the Nd:YAG laser. The total mean energy was 0.339+/-0.089 J. None of the eyes developed a clinically significant IOP spike (≥ 8 mmHg) at 1 h and 1 day after laser use. Only four eyes developed higher IOP at 1 h and all were ≤3 mmHg compared to baseline. The mean IOP was 13.8+/-2.5 mmHg at 1 h and 11.5+/-2.2 mmHg at 1 day, both were significantly lower than baseline (15.8+/-2.1 mmHg) (P < 0.001). Mean VA (logMAR) was similar at 1 h post laser compared to baseline (0.23 vs 0.26). There was also no statistically significant difference in mean VA at other follow-up visits compared to baseline. Peripheral iridotomy closure was encountered in two (6.1%) eyes, one at 1 month and another at 6 months follow-up. There were no complications including hyphema, peripheral anterior synechia formation nor prolonged inflammation throughout the follow-up period. There was no significant loss in corneal endothelial cell counts at 6 months (2255+/-490) compared to baseline (2303+/-386) (P = 0.347). Sequential LPI using an ultralow fluence pattern scanning laser, followed by a Nd:YAG laser, is safe and efficacious, and produces no IOP spike in dark irides of primary angle-closure suspects. Further studies to investigate its role in the treatment of other angle-closure conditions are warranted.

Reduced intraocular pressure after cataract surgery in patients with narrow angles and chronic angle-closure glaucoma.

PubMed

Brown, Reay H; Zhong, Le; Whitman, Allison L; Lynch, Mary G; Kilgo, Patrick D; Hovis, Kristen L

2014-10-01

To evaluate the effect of cataract surgery on intraocular pressure (IOP) in patients with narrow angles and chronic angle-closure glaucoma (ACG) and to determine whether the change in IOP was correlated with the preoperative pressure, axial length (AL), and anterior chamber depth (ACD). Private practice, Atlanta, Georgia, USA. Retrospective case series. Charts of patients with narrow angles or chronic ACG who had cataract surgery were reviewed. All eyes had previous laser iridotomies. Data recorded included preoperative and postoperative IOP, AL, and ACD. The preoperative IOP was used to stratify eyes into 4 groups. The charts of 56 patients (83 eyes) were reviewed. The mean reduction IOP in all eyes was 3.28 mm Hg (18%), with 88% having a decrease in IOP. There was a significant correlation between preoperative IOP and the magnitude of IOP reduction (r = 0.68, P < .001). The mean decrease in IOP was 5.3 mm Hg in eyes with a preoperative IOP above 20 mm Hg, 4.6 mm Hg in the over 18 to 20 mm Hg group, 2.5 mm Hg in the over 15 to 18 mm Hg group, and 1.4 mm Hg in the 15 mm Hg or less group. The mean follow-up was 3.0 years ± 2.3 (SD). Cataract surgery reduced IOP in patients with narrow angles and chronic ACG. The magnitude of reduction was highly correlated with preoperative IOP and weakly correlated with ACD. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Evaluating Models Of The Neutral, Barotropic Planetary Boundary Layer Using Integral Measures: Part Ii. Modelling Observed Conditions

NASA Astrophysics Data System (ADS)

Hess, G. D.; Garratt, J. R.

The steady-state, horizontally homogeneous, neutral, barotropiccase forms the foundation of our theoretical understanding of the planetary boundary layer (PBL).While simple analytical models and first-order closure models simulate atmospheric observationsof this case well, more sophisticated models, in general, do not. In this paperwe examine how well three higher-order closure models, E - - l, E - l, and LRR - l,which have been especially modified for PBL applications, perform in predicting the behaviour of thecross-isobaric angle 0, the geostrophic drag coefficient Cg, and the integral of the dissipationrate over the boundary layer, as a function of the surface Rossby number Ro. For comparison we alsoexamine the performance of three first-order closure mixing-length models, two proposed byA. K. Blackadar and one by H. H. Lettau, and the performance of the standard model forsecond-order closure and a modification of it designed to reduce the overprediction of turbulence inthe upper part of the boundary layer.

Impact of Different Standard Type A7A Drum Closure-Ring Practices on Gasket Contraction and Bolt Closure Distance– 15621

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ketusky, Edward; Blanton, Paul; Bobbitt, John H.

The Department of Energy, the Savannah River National Laboratory, several manufacturers of specification drums, and the United States Department of Transportation (DOT) are collaborating in the development of a guidance document for DOE contractors and vendors who wish to qualify containers to DOT 7A Type A requirements. Currently, the effort is focused on DOT 7A Type A 208-liter (55-gallons) drums with a standard 12-gauge bolted closure ring. The U.S. requirements, contained in Title 49, Part 178.350 “Specification 7A; general packaging, Type A specifies a competent authority review of the packaging is not required for the transport of (Class 7) radioactivemore » material containing less than Type A quantities of radioactive material. For Type AF drums, a 4 ft. regulatory free drop must be performed, such that the drum “suffers maximum damage.” Although the actual orientation is not defined by the specification, recent studies suggest that maximum damage would result from a shallow angle top impact, where kinetic energy is transferred to the lid, ultimately causing heavy damage to the lid, or even worse, causing the lid to come off. Since each vendor develops closure recommendations/procedures for the drums they manufacture, key parameters applied to drums during closing vary based on vendor. As part of the initial phase of the collaboration, the impact of the closure variants on the ability of the drum to suffer maximum damage is investigated. Specifically, closure testing is performed varying: 1) the amount of torque applied to the closure ring bolt; and, 2) stress relief protocol, including: a) weight of hammer; and, b) orientation that the hammer hits the closure ring. After closure, the amount of drum lid gasket contraction and the distance that the closure bolt moves through the closure ring is measured.« less

Plateau Iris - Therapeutic options and functional results after treatment.

PubMed

Feraru, Crenguța; Bâlha, Andrei; Aursulesei, Victor; Filip, Andrei; Pantalon, Anca

2017-01-01

We present the therapeutic options and functional results in patients with plateau iris (syndrome or configuration) in consecutive case series. Material and method: Our study included newly diagnosed patients with acute angle closure by "plateau iris" (configuration or syndrome), between June 2016 and April 2017. Series of 8 consecutive patients met the inclusion criteria, all being females. All the patients underwent an individualized treatment according to the underlying mechanism and evolution. Functional results (visual acuity, IOP, topical medication) were reported in the current paper. Results: For 10 months, we diagnosed 14 eyes, from 9 patients with acute angle closure by Plateau Iris, distributed as it follows: 6 eyes with closed angle glaucoma (optic disk and visual field changes), 8 eyes with plateau iris syndrome and 2 eyes with plateau iris configuration. 7/ 8 patients were misdiagnosed with primary open angle glaucoma, whereas only one patient had the correct diagnosis of closed angle glaucoma and underwent peripheral laser iridotomy. As treatment options in our study, we recommended and performed argon laser peripheral iridoplasty + iridotomy in 10/ 14 eyes, cataract lens was extracted in 4 eyes and then replaced with PC-IOL, whereas 2 eyes required a filtering anti-glaucoma surgery (trabeculectomy + PI). 2 eyes from the same patient could not be treated as intended as the patient refused the treatment. In this unique case, Pilocarpine (4%) was temporarily indicated. Conclusion: Plateau iris represents a diagnostic trap, but based on a thorough gonioscopic examination and a good patient history, the right diagnosis can be made, all along with a correct therapeutic approach.

Relationship between intraocular pressure and angle configuration: an anterior segment OCT study.

PubMed

Chong, Rachel S; Sakata, Lisandro M; Narayanaswamy, Arun K; Ho, Sue-Wei; He, Mingguang; Baskaran, Mani; Wong, Tien Yin; Perera, Shamira A; Aung, Tin

2013-03-05

To assess the relationship between intraocular pressure (IOP) and anterior chamber angle (ACA) configuration as assessed by gonioscopy and anterior segment optical coherence tomography (AS-OCT). A total of 2045 subjects aged 50 years and older, were recruited from a community clinic and underwent AS-OCT, Goldmann applanation tonometry, and gonioscopy. A quadrant was classified as closed on gonioscopy if the posterior trabecular meshwork could not be seen. A closed quadrant on AS-OCT was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. Customized software (Zhongshan Angle Assessment Program, Guangzhou, China) was used to measure AS-OCT parameters on AS-OCT scans, including anterior chamber depth, area, and volume; iris thickness (IT) and curvature; lens vault; angle opening distance; and trabecular-iris space area. IOP values were adjusted for age, sex, diabetes and hypertension status, body mass index, central corneal thickness, and presence of peripheral anterior synechiae. Mean age of study subjects was 63.2 ± 8.0 years, 52.6% were female, and 89.4% were Chinese. Mean IOP was 14.8 ± 2.4 mm Hg (range 826). IOP (mean ± SE) increased with number of quadrants with gonioscopic angle closure (none: 14.6 ± 0.2; one: 14.7 ± 0.3; two: 15.0 ± 0.3; three: 15.0 ± 0.3; four: 15.6 ± 0.3 mm Hg; P < 0.001), and on AS-OCT (none: 14.7 ± 0.2; one: 15.0 ± 0.2; two: 14.8 ± 0.2; three: 15.1 ± 0.3; four: 16.0 ± 0.3 mm Hg; P < 0.001). IOP also increased in association with most of the ACA quantitative parameters measured on AS-OCT images, except for IT and lens vault. There was an association between the extent of angle closure, as assessed on AS-OCT and gonioscopy, with increasing IOP.

A proposed simple method for measurement in the anterior chamber angle: biometric gonioscopy.

PubMed

Congdon, N G; Spaeth, G L; Augsburger, J; Klancnik, J; Patel, K; Hunter, D G

1999-11-01

To design a system of gonioscopy that will allow greater interobserver reliability and more clearly defined screening cutoffs for angle closure than current systems while being simple to teach and technologically appropriate for use in rural Asia, where the prevalence of angle-closure glaucoma is highest. Clinic-based validation and interobserver reliability trial. Study 1: 21 patients 18 years of age and older recruited from a university-based specialty glaucoma clinic; study 2: 32 patients 18 years of age and older recruited from the same clinic. In study 1, all participants underwent conventional gonioscopy by an experienced observer (GLS) using the Spaeth system and in the same eye also underwent Scheimpflug photography, ultrasonographic measurement of anterior chamber depth and axial length, automatic refraction, and biometric gonioscopy with measurement of the distance from iris insertion to Schwalbe's line using a reticule based in the slit-lamp ocular. In study 2, all participants underwent both conventional gonioscopy and biometric gonioscopy by an experienced gonioscopist (NGC) and a medical student with no previous training in gonioscopy (JK). Study 1: The association between biometric gonioscopy and conventional gonioscopy, Scheimpflug photography, and other factors known to correlate with the configuration of the angle. Study 2: Interobserver agreement using biometric gonioscopy compared to that obtained with conventional gonioscopy. In study 1, there was an independent, monotonic, statistically significant relationship between biometric gonioscopy and both Spaeth angle (P = 0.001, t test) and Spaeth insertion (P = 0.008, t test) grades. Biometric gonioscopy correctly identified six of six patients with occludable angles according to Spaeth criteria. Biometric gonioscopic grade was also significantly associated with the anterior chamber angle as measured by Scheimpflug photography (P = 0.005, t test). In study 2, the intraclass correlation coefficient between graders for biometric gonioscopy (0.97) was higher than for Spaeth angle grade (0.72) or Spaeth insertion grade (0.84). Biometric gonioscopy correlates well with other measures of the anterior chamber angle, shows a higher degree of interobserver reliability than conventional gonioscopy, and can readily be learned by an inexperienced observer.

Uncertainty Quantification of Turbulence Model Closure Coefficients for Transonic Wall-Bounded Flows

NASA Technical Reports Server (NTRS)

Schaefer, John; West, Thomas; Hosder, Serhat; Rumsey, Christopher; Carlson, Jan-Renee; Kleb, William

2015-01-01

The goal of this work was to quantify the uncertainty and sensitivity of commonly used turbulence models in Reynolds-Averaged Navier-Stokes codes due to uncertainty in the values of closure coefficients for transonic, wall-bounded flows and to rank the contribution of each coefficient to uncertainty in various output flow quantities of interest. Specifically, uncertainty quantification of turbulence model closure coefficients was performed for transonic flow over an axisymmetric bump at zero degrees angle of attack and the RAE 2822 transonic airfoil at a lift coefficient of 0.744. Three turbulence models were considered: the Spalart-Allmaras Model, Wilcox (2006) k-w Model, and the Menter Shear-Stress Trans- port Model. The FUN3D code developed by NASA Langley Research Center was used as the flow solver. The uncertainty quantification analysis employed stochastic expansions based on non-intrusive polynomial chaos as an efficient means of uncertainty propagation. Several integrated and point-quantities are considered as uncertain outputs for both CFD problems. All closure coefficients were treated as epistemic uncertain variables represented with intervals. Sobol indices were used to rank the relative contributions of each closure coefficient to the total uncertainty in the output quantities of interest. This study identified a number of closure coefficients for each turbulence model for which more information will reduce the amount of uncertainty in the output significantly for transonic, wall-bounded flows.

Incidence and Management of Glaucoma in Vogt Koyanagi Harada Disease.

PubMed

Pandey, Amit; Balekudaru, Shantha; Venkatramani, Devendra V; George, Amala E; Lingam, Vijaya; Biswas, Jyotirmay

2016-08-01

To analyse the prevalence, incidence, and risk factors of glaucoma in Vogt Koyanagi Harada (VKH) disease and study the changes in visual acuity and intraocular pressure (IOP) with treatment. Retrospective chart analysis of 448 eyes of 224 patients of Indian origin diagnosed with VKH disease from January 1990 to December 2013, who had a minimum follow-up of 3 months was performed. Seventy-one eyes (15.8%) developed sustained elevation in IOP. The prevalence of glaucoma at presentation was 15.8% and the cumulative incidence of glaucoma was 11.7%. The mechanisms of glaucoma were open-angle glaucoma in 46 eyes, (64.8%), angle closure in 21 eyes (29.6%), and of combined mechanisms in the remainder (4 eyes, 5.6%). Acute angle-closure crisis developed in 9 eyes (12.6%). Uveal effusion (odds ratio 9.47; confidence interval, 4.08-20.03) and increased number of recurrences (odds ratio 1.31; confidence interval, 1.13-1.53) were found to be significant risk factors for the development of glaucoma. Successful control of IOP was achieved in 64% at 12 months using medical/ laser treatment for glaucoma and was 50 % at 12 months following surgical management. Glaucoma is a frequent complication of uveitis in VKH disease. Presence of uveal effusion and increased number of recurrences of inflammation are significant risk factors.

The Effect of Surface Electrical Stimulation on Vocal Fold Position

PubMed Central

Humbert, Ianessa A.; Poletto, Christopher J.; Saxon, Keith G.; Kearney, Pamela R.; Ludlow, Christy L.

2008-01-01

Objectives/Hypothesis Closure of the true and false vocal folds is a normal part of airway protection during swallowing. Individuals with reduced or delayed true vocal fold closure can be at risk for aspiration and benefit from intervention to ameliorate the problem. Surface electrical stimulation is currently used during therapy for dysphagia, despite limited knowledge of its physiological effects. Design Prospective single effects study. Methods The immediate physiological effect of surface stimulation on true vocal fold angle was examined at rest in 27 healthy adults using ten different electrode placements on the submental and neck regions. Fiberoptic nasolaryngoscopic recordings during passive inspiration were used to measure change in true vocal fold angle with stimulation. Results Vocal fold angles changed only to a small extent during two electrode placements (p ≤ 0.05). When two sets of electrodes were placed vertically on the neck the mean true vocal fold abduction was 2.4 degrees; while horizontal placements of electrodes in the submental region produced a mean adduction of 2.8 degrees (p=0.03). Conclusions Surface electrical stimulation to the submental and neck regions does not produce immediate true vocal fold adduction adequate for airway protection during swallowing and one position may produce a slight increase in true vocal fold opening. PMID:18043496

SURBAL: computerized metes and bounds surveying

Treesearch

Roger N. Baughman; James H. Patric

1970-01-01

A computer program has been developed at West Virginia University for use in metes and bounds surveying. Stations, slope distances, slope angles, and bearings are primary information needed for this program. Other information needed may include magnetic deviation, acceptable closure error, desired map scale, and title designation. SURBAL prints out latitudes and...

Gonioscopy.

PubMed

Thomas, R; Thomas, S; Chandrashekar, G

1998-12-01

Gonioscopy forms part of a complete ophthalmic examination and is mandatory for the diagnosis and management of glaucoma. Gonioscopy permits identification of eyes at risk for closure and detects angle abnormalities that could have diagnostic and therapeutic implications. The technique of gonioscopy, its value in management, and guidelines for routine use are discussed in this paper.

Pore formation and pore closure in poly(D,L-lactide-co-glycolide) films.

PubMed

Fredenberg, Susanne; Wahlgren, Marie; Reslow, Mats; Axelsson, Anders

2011-03-10

Pore formation and pore closure in poly(D,L-lactide-co-glycolide)-based drug delivery systems are two important processes as they control the release of the encapsulated drug. The phenomenon pore closure was investigated by studying the effects of the pH and the temperature of the release medium, and the properties of the polymer. Poly(D,L-lactide-co-glycolide) (PLG) films were subjected to a pore forming pre-treatment, and then pore closure was observed simultaneously with changes in glass transition temperature, wettability (contact angle), water absorption and mass remaining. To further understand the effect of pH, combined pore formation and pore closure were studied at different pH values. Pore closure was increased in a release medium with low pH, with a low-molecular-weight PLG of relatively low degree of hydrophobicity, or at high temperature. Pore closure occurred by two different mechanisms, one based on polymer-polymer interactions and one on polymer-water interactions. The mobility of the PLG chains also played an important role. The surface of the PLG films were more porous at pH 5-6 than at lower or higher pH, as pore formation was relatively fast and pore closure were less pronounced in this pH range. The pH had a significant impact on the porous structure, which should be kept in mind when evaluating experimental results, as the pH may be significantly decreased in vitro, in vivo and in situ. The results also show that the initial porosity is very important when using a high-molecular-weight PLG. Copyright © 2010 Elsevier B.V. All rights reserved.

[The questionnaire survey on glaucoma diagnosis and treatment in China (2016)].

PubMed

Zhang, Q; Cao, K; Kang, M T; Sun, Y X; Gan, J H; Tian, J X; Ran, A R; Zhang, X; Su, Y D; Li, S N

2017-02-11

Objective: To investigate the present situation of diagnosis and treatment for primary angle-closure glaucoma (PACG) and primary open-angle glaucoma (POAG) and awareness of the relevant progress among Chinese ophthalmologists. Methods: This study was a cross-sectional, non-randomized sampling survey. Participants were ophthalmologists who attended the 11st Chinese Glaucoma Society Congress during November 11 to 12, 2016. They were invited to fill out a questionnaire. The questionnaire included participants' basic information and their knowledge about glaucoma diagnosis and treatment. The data collected through questionnaire were analyzed with SAS9.4. Results: A total of 450 questionnaires were distributed and 372 valid questionnaires were retrieved, with a response rate of 82. 7%(372/450). ISGEO classification system was adopted by 58.9% (219/372) of the participants as the diagnostic criteria for PACG. Of the respondents, 48.1% (179/372) of the participants believed that "anterior chamber angle closure mechanism-based PACG classification system" was more instructive for treatment, the percentage was higher than ISGEO classification system (42.2%, 157/372). Most (72.3%, 269/372) of the participants knew the 3-minute dark room prone test, but only 27.7%(103/372) of them applied it in clinical practice. A total of 83.4%(310/372) of the participants believed that low cerebrospinal fluid pressure is a risk factor for POAG. In all, 71.8% (267/372) of the participants reported that their institutes had applied compound trabeculectomy with adjustable suture, with 76.9%(286/372) of the participants agreeing that the adjustable suture reduced the rate of complications after trabeculectomy. Conclusions: Currently, both ISGEO classification system and anterior chamber angle closure mechanism-based PACG classification system were adopted in the diagnosis and treatment of glaucoma. Low cerebrospinal fluid pressure as new risk factors for POAG has been widely acknowledged and given attentions by Chinese ophthalmologists. The 3-minute darkroom prone test and compound trabeculectomy with adjustable suture still need to be promoted. (Chin J Ophthalmol, 2017, 53: 115-120) .

Comparison of gonioscopy and anterior segment ocular coherence tomography in detecting angle closure in different quadrants of the anterior chamber angle.

PubMed

Sakata, Lisandro M; Lavanya, Raghavan; Friedman, David S; Aung, Han T; Gao, Hong; Kumar, Rajesh S; Foster, Paul J; Aung, Tin

2008-05-01

To compare the performance of gonioscopy and anterior segment (AS) optical coherence tomography (OCT) in detecting angle closure in the different quadrants of the anterior chamber angle (ACA). Cross-sectional observational study. Five hundred two consecutive subjects more than 50 years of age with no previous ophthalmic problems recruited from a community clinic in Singapore. All subjects underwent gonioscopy and AS OCT imaging in the dark. Using gonioscopy, the ACA was graded using the Scheie system by a single examiner masked to AS OCT findings. The ACA in a particular quadrant was classified as closed if the posterior trabecular meshwork could not be seen on gonioscopy. A closed ACA on AS OCT imaging was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. After excluding eyes with poor image quality, a total of 423 right eyes were included in the analysis. A closed angle in at least 1 quadrant was observed in 59% of the eyes by AS OCT and in 33% of the eyes by gonioscopy (P<0.001), with fair agreement between the two methods (kappa = 0.40). The frequency of closed angles by AS OCT and gonioscopy were 48% versus 29% superiorly, 43% versus 22% inferiorly, 18% versus 14% nasally, and 12% versus 20% temporally, respectively. Of the 119 of 1692 quadrants that were closed on gonioscopy but open on AS OCT, a steep iris profile was present in 61 (51%) of 119 quadrants on AS OCT, and of the 276 of 1692 quadrants that were open on gonioscopy but closed on AS OCT, 196 (71%) of 276 quadrants showed short iridoangle contact on AS OCT. The highest rates of closed angles on gonioscopy and AS OCT images were observed in the superior quadrant. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior quadrants. Variations in the iris profile and level of iridoangle contact also may explain some of the differences seen between gonioscopy and AS OCT.

Accurate small and wide angle x-ray scattering profiles from atomic models of proteins and nucleic acids

NASA Astrophysics Data System (ADS)

Nguyen, Hung T.; Pabit, Suzette A.; Meisburger, Steve P.; Pollack, Lois; Case, David A.

2014-12-01

A new method is introduced to compute X-ray solution scattering profiles from atomic models of macromolecules. The three-dimensional version of the Reference Interaction Site Model (RISM) from liquid-state statistical mechanics is employed to compute the solvent distribution around the solute, including both water and ions. X-ray scattering profiles are computed from this distribution together with the solute geometry. We describe an efficient procedure for performing this calculation employing a Lebedev grid for the angular averaging. The intensity profiles (which involve no adjustable parameters) match experiment and molecular dynamics simulations up to wide angle for two proteins (lysozyme and myoglobin) in water, as well as the small-angle profiles for a dozen biomolecules taken from the BioIsis.net database. The RISM model is especially well-suited for studies of nucleic acids in salt solution. Use of fiber-diffraction models for the structure of duplex DNA in solution yields close agreement with the observed scattering profiles in both the small and wide angle scattering (SAXS and WAXS) regimes. In addition, computed profiles of anomalous SAXS signals (for Rb+ and Sr2+) emphasize the ionic contribution to scattering and are in reasonable agreement with experiment. In cases where an absolute calibration of the experimental data at q = 0 is available, one can extract a count of the excess number of waters and ions; computed values depend on the closure that is assumed in the solution of the Ornstein-Zernike equations, with results from the Kovalenko-Hirata closure being closest to experiment for the cases studied here.

Agreement of glaucoma specialists and experienced optometrists in gonioscopy and optic disc evaluation

PubMed Central

Kumar, Addepalli U.; Jonnadula, Ganesh B.; Garudadri, Chandrasekhar; Rao, Harsha L.; Senthil, Sirisha; Papas, Eric B.; Sankaridurg, Padmaja; Khanna, Rohit C.

2013-01-01

Purpose To compare the diagnostic performance of glaucoma specialists and experienced optometrists in gonioscopy and optic disc assessment. Methods This study was done to validate the diagnostic performance of two experienced optometrists for using their skills of detecting glaucoma using gonioscopy and optic disc assessment in a major epidemiological study, the L V Prasad Eye Institute Glaucoma Epidemiology and Molecular Genetics Study (LVPEI-GLEAMS). Gonioscopic findings for 150 eyes were categorized as 0, 1 and 2 for open angle, primary angle closure suspect (PACS) and primary angle closure (PAC) respectively. Optic disc findings for 200 eyes were categorized as 0, 1 and 2 for normal, suspects and glaucomatous respectively. Weighted kappa (κ) and diagnostic accuracy parameters were calculated. Two optometrists (#1 and #2) participated in the study. Results Agreement between glaucoma specialists and optometrist for interpretation of gonioscopy to discriminate PACS and PAC from open angles and for interpretation of optic disc to discriminate glaucomatous and suspicious discs from normal, the kappa (κ) was 0.92 and 0.84 and 0.90 and 0.89 for optometrists #1 and #2 respectively. Sensitivities and specificities were above 90% for gonioscopy. Optic disc evaluation had specificities greater than 95% to discriminate normal from glaucomatous discs while the sensitivities were 83% and 93% for optometrists #1 and #2 respectively. Conclusion Agreement between optometrists and glaucoma specialists, in diagnostic performance of gonioscopy and optic assessment was excellent with high sensitivity and specificity. Hence, we conclude that the experienced optometrists can detect glaucoma accurately in the LVPEI-GLEAMS.

Biometric Factors Associated With Acute Primary Angle Closure: Comparison of the Affected and Fellow Eye.

PubMed

Atalay, Eray; Nongpiur, Monisha E; Baskaran, Mani; Sharma, Sourabh; Perera, Shamira A; Aung, Tin

2016-10-01

To compare ocular biometric and anterior segment parameters between the affected and fellow eye in subjects with acute primary angle closure (APAC). We evaluated 76 subjects with unilateral APAC who had undergone bilateral laser peripheral iridotomy before enrollment. Imaging was done using anterior segment optical coherence tomography and a customized software was used to measure the following: angle opening distance (AOD750); trabecular-iris space area (TISA750); iris thickness (IT750); iris curvature (ICURV); iris area (IAREA); anterior chamber depth; area and volume (ACD; ACA and ACV); anterior chamber width (ACW); anterior vault (ACD+LV); lens vault (LV); and pupil diameter (PD). We used A-scan ultrasonography to measure axial length (AL) and lens thickness (LT). Mean differences in ocular biometric and anterior segment parameters were assessed using linear mixed model adjusting for PD. A total of 53 subjects (36 females, 67.9%) with a mean age of 62.7 ± 8.1 years were analyzed after excluding 17 unanalyzable images in at least one eye. Affected eyes had shallower ACD, smaller ACA, ACV, anterior vault, TISA750, AOD750, and ICURV (all P < 0.05). Axial length, ACW, LV, LT, IAREA, and IT750 did not differ between the eyes. In the affected eyes, IT750 was significantly associated AOD750 (P < 0.05); whereas in the fellow eyes, IT750 and AL was predictive of AOD750 (all P < 0.05). Eyes with previous APAC had smaller anterior segment dimensions when compared with their fellow eyes. Iris thickness was the strongest predictor of angle width in both affected and fellow eyes.

Genome-wide association study identifies five new susceptibility loci for primary angle closure glaucoma.

PubMed

Khor, Chiea Chuen; Do, Tan; Jia, Hongyan; Nakano, Masakazu; George, Ronnie; Abu-Amero, Khaled; Duvesh, Roopam; Chen, Li Jia; Li, Zheng; Nongpiur, Monisha E; Perera, Shamira A; Qiao, Chunyan; Wong, Hon-Tym; Sakai, Hiroshi; Barbosa de Melo, Mônica; Lee, Mei-Chin; Chan, Anita S; Azhany, Yaakub; Dao, Thi Lam Huong; Ikeda, Yoko; Perez-Grossmann, Rodolfo A; Zarnowski, Tomasz; Day, Alexander C; Jonas, Jost B; Tam, Pancy O S; Tran, Tuan Anh; Ayub, Humaira; Akhtar, Farah; Micheal, Shazia; Chew, Paul T K; Aljasim, Leyla A; Dada, Tanuj; Luu, Tam Thi; Awadalla, Mona S; Kitnarong, Naris; Wanichwecharungruang, Boonsong; Aung, Yee Yee; Mohamed-Noor, Jelinar; Vijayan, Saravanan; Sarangapani, Sripriya; Husain, Rahat; Jap, Aliza; Baskaran, Mani; Goh, David; Su, Daniel H; Wang, Huaizhou; Yong, Vernon K; Yip, Leonard W; Trinh, Tuyet Bach; Makornwattana, Manchima; Nguyen, Thanh Thu; Leuenberger, Edgar U; Park, Ki-Ho; Wiyogo, Widya Artini; Kumar, Rajesh S; Tello, Celso; Kurimoto, Yasuo; Thapa, Suman S; Pathanapitoon, Kessara; Salmon, John F; Sohn, Yong Ho; Fea, Antonio; Ozaki, Mineo; Lai, Jimmy S M; Tantisevi, Visanee; Khaing, Chaw Chaw; Mizoguchi, Takanori; Nakano, Satoko; Kim, Chan-Yun; Tang, Guangxian; Fan, Sujie; Wu, Renyi; Meng, Hailin; Nguyen, Thi Thuy Giang; Tran, Tien Dat; Ueno, Morio; Martinez, Jose Maria; Ramli, Norlina; Aung, Yin Mon; Reyes, Rigo Daniel; Vernon, Stephen A; Fang, Seng Kheong; Xie, Zhicheng; Chen, Xiao Yin; Foo, Jia Nee; Sim, Kar Seng; Wong, Tina T; Quek, Desmond T; Venkatesh, Rengaraj; Kavitha, Srinivasan; Krishnadas, Subbiah R; Soumittra, Nagaswamy; Shantha, Balekudaru; Lim, Boon-Ang; Ogle, Jeanne; de Vasconcellos, José P C; Costa, Vital P; Abe, Ricardo Y; de Souza, Bruno B; Sng, Chelvin C; Aquino, Maria C; Kosior-Jarecka, Ewa; Fong, Guillermo Barreto; Tamanaja, Vania Castro; Fujita, Ricardo; Jiang, Yuzhen; Waseem, Naushin; Low, Sancy; Pham, Huan Nguyen; Al-Shahwan, Sami; Craven, E Randy; Khan, Muhammad Imran; Dada, Rrima; Mohanty, Kuldeep; Faiq, Muneeb A; Hewitt, Alex W; Burdon, Kathryn P; Gan, Eng Hui; Prutthipongsit, Anuwat; Patthanathamrongkasem, Thipnapa; Catacutan, Mary Ann T; Felarca, Irene R; Liao, Chona S; Rusmayani, Emma; Istiantoro, Vira Wardhana; Consolandi, Giulia; Pignata, Giulia; Lavia, Carlo; Rojanapongpun, Prin; Mangkornkanokpong, Lerprat; Chansangpetch, Sunee; Chan, Jonathan C H; Choy, Bonnie N K; Shum, Jennifer W H; Than, Hlaing May; Oo, Khin Thida; Han, Aye Thi; Yong, Victor H; Ng, Xiao-Yu; Goh, Shuang Ru; Chong, Yaan Fun; Hibberd, Martin L; Seielstad, Mark; Png, Eileen; Dunstan, Sarah J; Chau, Nguyen Van Vinh; Bei, Jinxin; Zeng, Yi Xin; Karkey, Abhilasha; Basnyat, Buddha; Pasutto, Francesca; Paoli, Daniela; Frezzotti, Paolo; Wang, Jie Jin; Mitchell, Paul; Fingert, John H; Allingham, R Rand; Hauser, Michael A; Lim, Soon Thye; Chew, Soo Hong; Ebstein, Richard P; Sakuntabhai, Anavaj; Park, Kyu Hyung; Ahn, Jeeyun; Boland, Greet; Snippe, Harm; Stead, Richard; Quino, Raquel; Zaw, Su Nyunt; Lukasik, Urszula; Shetty, Rohit; Zahari, Mimiwati; Bae, Hyoung Won; Oo, Nay Lin; Kubota, Toshiaki; Manassakorn, Anita; Ho, Wing Lau; Dallorto, Laura; Hwang, Young Hoon; Kiire, Christine A; Kuroda, Masako; Djamal, Zeiras Eka; Peregrino, Jovell Ian M; Ghosh, Arkasubhra; Jeoung, Jin Wook; Hoan, Tung S; Srisamran, Nuttamon; Sandragasu, Thayanithi; Set, Saw Htoo; Doan, Vi Huyen; Bhattacharya, Shomi S; Ho, Ching-Lin; Tan, Donald T; Sihota, Ramanjit; Loon, Seng-Chee; Mori, Kazuhiko; Kinoshita, Shigeru; Hollander, Anneke I den; Qamar, Raheel; Wang, Ya-Xing; Teo, Yik Y; Tai, E-Shyong; Hartleben-Matkin, Curt; Lozano-Giral, David; Saw, Seang Mei; Cheng, Ching-Yu; Zenteno, Juan C; Pang, Chi Pui; Bui, Huong T T; Hee, Owen; Craig, Jamie E; Edward, Deepak P; Yonahara, Michiko; Neto, Jamil Miguel; Guevara-Fujita, Maria L; Xu, Liang; Ritch, Robert; Liza-Sharmini, Ahmad Tajudin; Wong, Tien Y; Al-Obeidan, Saleh; Do, Nhu Hon; Sundaresan, Periasamy; Tham, Clement C; Foster, Paul J; Vijaya, Lingam; Tashiro, Kei; Vithana, Eranga N; Wang, Ningli; Aung, Tin

2016-05-01

Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. We conducted a genome-wide association study (GWAS) followed by replication in a combined total of 10,503 PACG cases and 29,567 controls drawn from 24 countries across Asia, Australia, Europe, North America, and South America. We observed significant evidence of disease association at five new genetic loci upon meta-analysis of all patient collections. These loci are at EPDR1 rs3816415 (odds ratio (OR) = 1.24, P = 5.94 × 10(-15)), CHAT rs1258267 (OR = 1.22, P = 2.85 × 10(-16)), GLIS3 rs736893 (OR = 1.18, P = 1.43 × 10(-14)), FERMT2 rs7494379 (OR = 1.14, P = 3.43 × 10(-11)), and DPM2-FAM102A rs3739821 (OR = 1.15, P = 8.32 × 10(-12)). We also confirmed significant association at three previously described loci (P < 5 × 10(-8) for each sentinel SNP at PLEKHA7, COL11A1, and PCMTD1-ST18), providing new insights into the biology of PACG.

Numerical exploration of non-axisymmetric divertor closure in the small angle slot (SAS) divertor at DIII-D

DOE PAGES

Frerichs, H.; Schmitz, O.; Covele, B.; ...

2018-02-28

Numerical simulations of toroidal asymmetries in a tightly baffled small angle slot (SAS) divertor on the DIII-D tokamak show that toroidal asymmetries in divertor closure result in (non-axisymmetric) local onset of detachment within a density window of 10-15% on top of the nominal threshold separatrix density. The SAS divertor is explored at DIII-D for improving access to cold, dissipative/detached divertor conditions. The narrow width of the slot divertor coupled with a small magnetic field line-to-target angle facilitates the buildup of neutral density, thereby increasing radiative and neutrals-related (atoms and molecules) losses in the divertor. Therefore, small changes in the strikemore » point location can be expected to have a large impact on diverter conditions. The combination of misaligned slot structure and non-axisymmetric perturbations to the magnetic field configuration causes the strike point to move along the divertor target plate, possibly leaving the diverter slot at some locations. The latter extreme case essentially introduces an opening in the divertor slot from where recycling neutrals can easily escape, and thereby degrade the performance of the slot divertor. Such a strike point dislocation is approximated by a finite gap in the divertor baffle for which three dimensional edge plasma and neutral gas simulations are performed with the EMC3-EIRENE code.« less

Numerical exploration of non-axisymmetric divertor closure in the small angle slot (SAS) divertor at DIII-D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frerichs, H.; Schmitz, O.; Covele, B.

Numerical simulations of toroidal asymmetries in a tightly baffled small angle slot (SAS) divertor on the DIII-D tokamak show that toroidal asymmetries in divertor closure result in (non-axisymmetric) local onset of detachment within a density window of 10-15% on top of the nominal threshold separatrix density. The SAS divertor is explored at DIII-D for improving access to cold, dissipative/detached divertor conditions. The narrow width of the slot divertor coupled with a small magnetic field line-to-target angle facilitates the buildup of neutral density, thereby increasing radiative and neutrals-related (atoms and molecules) losses in the divertor. Therefore, small changes in the strikemore » point location can be expected to have a large impact on diverter conditions. The combination of misaligned slot structure and non-axisymmetric perturbations to the magnetic field configuration causes the strike point to move along the divertor target plate, possibly leaving the diverter slot at some locations. The latter extreme case essentially introduces an opening in the divertor slot from where recycling neutrals can easily escape, and thereby degrade the performance of the slot divertor. Such a strike point dislocation is approximated by a finite gap in the divertor baffle for which three dimensional edge plasma and neutral gas simulations are performed with the EMC3-EIRENE code.« less

Numerical exploration of non-axisymmetric divertor closure in the small angle slot (SAS) divertor at DIII-D

NASA Astrophysics Data System (ADS)

Frerichs, H.; Schmitz, O.; Covele, B.; Feng, Y.; Guo, H. Y.; Hill, D.

2018-05-01

Numerical simulations of toroidal asymmetries in a tightly baffled small angle slot (SAS) divertor on the DIII-D tokamak show that toroidal asymmetries in divertor closure result in (non-axisymmetric) local onset of detachment within a density window of 10-15% on top of the nominal threshold separatrix density. The SAS divertor is explored at DIII-D for improving access to cold, dissipative/detached divertor conditions. The narrow width of the slot divertor coupled with a small magnetic field line-to-target angle facilitates the buildup of neutral density, thereby increasing radiative and neutrals-related (atoms and molecules) losses in the divertor. Small changes in the strike point location can be expected to have a large impact on divertor conditions. The combination of misaligned slot structure and non-axisymmetric perturbations to the magnetic field configuration causes the strike point to move along the divertor target plate, possibly leaving the divertor slot at some locations. The latter extreme case essentially introduces an opening in the divertor slot from where recycling neutrals can easily escape, and thereby degrade the performance of the slot divertor. Such a strike point dislocation is approximated by a finite gap in the divertor baffle for which 3D edge plasma and neutral gas simulations are performed with the EMC3-EIRENE code.

A Novel Method of Quantitative Anterior Chamber Depth Estimation Using Temporal Perpendicular Digital Photography

PubMed Central

Zamir, Ehud; Kong, George Y.X.; Kowalski, Tanya; Coote, Michael; Ang, Ghee Soon

2016-01-01

Purpose We hypothesize that: (1) Anterior chamber depth (ACD) is correlated with the relative anteroposterior position of the pupillary image, as viewed from the temporal side. (2) Such a correlation may be used as a simple quantitative tool for estimation of ACD. Methods Two hundred sixty-six phakic eyes had lateral digital photographs taken from the temporal side, perpendicular to the visual axis, and underwent optical biometry (Nidek AL scanner). The relative anteroposterior position of the pupillary image was expressed using the ratio between: (1) lateral photographic temporal limbus to pupil distance (“E”) and (2) lateral photographic temporal limbus to cornea distance (“Z”). In the first chronological half of patients (Correlation Series), E:Z ratio (EZR) was correlated with optical biometric ACD. The correlation equation was then used to predict ACD in the second half of patients (Prediction Series) and compared to their biometric ACD for agreement analysis. Results A strong linear correlation was found between EZR and ACD, R = −0.91, R2 = 0.81. Bland-Altman analysis showed good agreement between predicted ACD using this method and the optical biometric ACD. The mean error was −0.013 mm (range −0.377 to 0.336 mm), standard deviation 0.166 mm. The 95% limits of agreement were ±0.33 mm. Conclusions Lateral digital photography and EZR calculation is a novel method to quantitatively estimate ACD, requiring minimal equipment and training. Translational Relevance EZ ratio may be employed in screening for angle closure glaucoma. It may also be helpful in outpatient medical clinic settings, where doctors need to judge the safety of topical or systemic pupil-dilating medications versus their risk of triggering acute angle closure glaucoma. Similarly, non ophthalmologists may use it to estimate the likelihood of acute angle closure glaucoma in emergency presentations. PMID:27540496

Few Skewed Disks Found in First Closure-Phase Survey of Herbig Ae/Be Stars

NASA Astrophysics Data System (ADS)

Monnier, J. D.; Berger, J.-P.; Millan-Gabet, R.; Traub, W. A.; Schloerb, F. P.; Pedretti, E.; Benisty, M.; Carleton, N. P.; Haguenauer, P.; Kern, P.; Labeye, P.; Lacasse, M. G.; Malbet, F.; Perraut, K.; Pearlman, M.; Zhao, M.

2006-08-01

Using the three-telescope IOTA interferometer on Mount Hopkins, we report results from the first near-infrared (λ=1.65 μm) closure-phase survey of young stellar objects (YSOs). These closure phases allow us to unambiguously detect departures from centrosymmetry (i.e., skew) in the emission pattern from YSO disks on the scale of ~4 mas, expected from generic ``flared disk'' models. Six of 14 targets showed small, yet statistically significant nonzero closure phases, with largest values from the young binary system MWC 361-A and the (pre-main-sequence?) Be star HD 45677. Our observations are quite sensitive to the vertical structure of the inner disk, and we confront the predictions of the ``puffed-up inner wall'' models of Dullemond, Dominik, & Natta (DDN). Our data support disk models with curved inner rims because the expected emission appears symmetrically distributed around the star over a wide range of inclination angles. In contrast, our results are incompatible with the models possessing vertical inner walls because they predict extreme skewness (i.e., large closure phases) from the near-IR disk emission that is not seen in our data. In addition, we also present the discovery of mysterious H-band ``halos'' (~5%-10% of light on scales 0.01"-0.50") around a few objects, a preliminary ``parametric imaging'' study for HD 45677, and the first astrometric orbit for the young binary MWC 361-A.

On the performance of the moment approximation for the numerical computation of fiber stress in turbulent channel flow

NASA Astrophysics Data System (ADS)

Gillissen, J. J. J.; Boersma, B. J.; Mortensen, P. H.; Andersson, H. I.

2007-03-01

Fiber-induced drag reduction can be studied in great detail by means of direct numerical simulation [J. S. Paschkewitz et al., J. Fluid Mech. 518, 281 (2004)]. To account for the effect of the fibers, the Navier-Stokes equations are supplemented by the fiber stress tensor, which depends on the distribution function of fiber orientation angles. We have computed this function in turbulent channel flow, by solving the Fokker-Planck equation numerically. The results are used to validate an approximate method for calculating fiber stress, in which the second moment of the orientation distribution is solved. Since the moment evolution equations contain higher-order moments, a closure relation is required to obtain as many equations as unknowns. We investigate the performance of the eigenvalue-based optimal fitted closure scheme [J. S. Cintra and C. L. Tucker, J. Rheol. 39, 1095 (1995)]. The closure-predicted stress and flow statistics in two-way coupled simulations are within 10% of the "exact" Fokker-Planck solution.

Low Speed Analysis of Mission Adaptive Flaps on a High Speed Civil Transport Configuration

NASA Technical Reports Server (NTRS)

Lessard, Victor R.

1999-01-01

Thin-layer Navier-Stokes analyses were done on a high speed civil transport configuration with mission adaptive leading-edge flaps. The flow conditions simulated were Mach = 0.22 and Reynolds number of 4.27 million for angles-of-attack ranging from 0 to 18 degrees. Two turbulence closure models were used. Analyses were done exclusively with the Baldwin-Lomax turbulence model at low angle-of-attack conditions. At high angles-of-attack where considerable flow separation and vortices occurred the Spalart-Allmaras turbulence model was also considered. The effects of flow transition were studied. Predicted aerodynamic forces, moment, and pressure are compared to experimental data obtained in the 14- by 22-Foot Subsonic Tunnel at NASA Langley. The forces and moments correlated well with experimental data in terms of trends. Drag and pitching moment were consistently underpredicted. Predicted surface pressures compared well with experiment at low angles-of-attack. Above 10 angle-of-attack the pressure comparisons were not as favorable. The two turbulent models affected the pressures on the flap considerably and neither produced correct results at the high angles-of-attack.

Hormonal regulation of floret closure of rice (Oryza sativa)

PubMed Central

Huang, Youming; Zeng, Xiaochun

2018-01-01

Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA), indole-3-butyric acid (IBA), 1-naphthalene-acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 3,6-dichloro-2-methoxybenzoic acid (DIC) and abscisic acid (ABA) on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013–2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of the varieties. PMID:29879200

Waves and tides responsible for the intermittent closure of the entrance of a small, sheltered tidal wetland at San Francisco, CA

USGS Publications Warehouse

Hanes, D.M.; Ward, K.; Erikson, L.H.

2011-01-01

Crissy Field Marsh (CFM; http://www.nps.gov/prsf/planyourvisit/crissy-field-marsh-and-beach.htm) is a small, restored tidal wetland located in the entrance to San Francisco Bay just east of the Golden Gate. The marsh is small but otherwise fairly typical of many such restored wetlands worldwide. The marsh is hydraulically connected to the bay and the adjacent Pacific Ocean by a narrow sandy channel. The channel often migrates and sometimes closes completely, which effectively blocks the tidal connection to the ocean and disrupts the hydraulics and ecology of the marsh. Field measurements of waves and tides have been examined in order to evaluate the conditions responsible for the intermittent closure of the marsh entrance. The most important factor found to bring about the entrance channel closure is the occurrence of large ocean waves. However, there were also a few closure events during times with relatively small offshore waves. Examination of the deep-water directional wave spectra during these times indicates the presence of a small secondary peak corresponding to long period swell from the southern hemisphere, indicating that CFM and San Francisco Bay in general may be more susceptible to long period ocean swell emanating from the south or southwest than the more common ocean waves coming from the northwest. The tidal records during closure events show no strong relationship between closures and tides, other than that closures tend to occur during multi-day periods with successively increasing high tides. It can be inferred from these findings that the most important process to the intermittent closure of the entrance to CFM is littoral sediment transport driven by the influence of ocean swell waves breaking along the CFM shoreline at oblique angles. During periods of large, oblique waves the littoral transport of sand likely overwhelms the scour potential of the tidal flow in the entrance channel. ?? 2011.

Level of education associated with ophthalmic diseases. The Beijing Eye Study.

PubMed

Xu, Liang; Wang, Ya Xing; Jonas, Jost B

2010-01-01

To determine associations between educational level and ophthalmic diseases in Chinese. The population-based Beijing Eye Study, performed in 2006, enrolled 3,251 participants (age: 45+ years) out of 4,439 subjects invited to participate (response rate: 73.2%). The participants underwent an interview including questions concerning their educational level, and a detailed ophthalmic examination. Data on the level of education were available for 3,221 (99.1%) subjects, with 1,484 (46.1%) subjects living in the rural region. The mean age was 60.4 +/- 10.1 years (range: 45-89 years). In a multivariate analysis, a higher level of education was significantly associated with myopic refractive error, higher best-corrected visual acuity, lower degree of nuclear cataract, and lower prevalence of angle-closure glaucoma, and with the systemic parameters of lower age, male gender, urban region, taller body height, and lower body mass index. It was not significantly associated with intraocular pressure, amount of subcapsular cataract and cortical cataract, cataract surgery, and the prevalences of diabetes mellitus, retinal vein occlusions, chronic open-angle glaucoma, and age-related macular degeneration, and with the systemic parameters of fasting serum concentrations of glucose, high-density lipoproteins, low-density lipoproteins, cholesterol and triglycerides, systolic and diastolic blood pressure. In the Greater Beijing area, a higher level of education was associated with myopic refractive error, higher best-corrected visual acuity, and lower prevalence of nuclear cataract and angle-closure glaucoma, after adjusting for the systemic parameters of younger age, male gender, urban region, taller body height, lower body mass index less smoking and less alcohol consumption. Educational level was not significantly associated with intraocular pressure, cortical cataract, blood pressure, and frequencies of age-related macular degeneration, retinal vein occlusions and chronic open-angle glaucoma.

Structure-Function Correlations using Scanning Laser Polarimetry in Primary Angle-Closure Glaucoma and Primary Open Angle Glaucoma

PubMed Central

Lee, Pei-Jung; Liu, Catherine Jui-Ling.; Wojciechowski, Robert; Bailey-Wilson, Joan E.; Cheng, Ching-Yu

2010-01-01

Purpose To assess the correlations between retinal nerve fiber layer (RNFL) thickness measured with scanning laser polarimetry (SLP) and visual field (VF) sensitivity in primary open angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Design Prospective, comparative, observational cases series Methods Fifty patients with POAG and 56 with PACG were examined using SLP with variable corneal compensation (GDx VCC) and Humphrey VF analyzer between August 2005 and July 2006 at Taipei Veterans General Hospital. Correlations between RNFL thickness and VF sensitivity, expressed as mean sensitivity (MS) in both decibel (dB) and 1/Lambert (L) scales, were estimated by Spearman's rank correlation coefficient (rs) and multivariate median regression models (pseudo R2). The correlations were determined globally and for six RNFL sectors and their corresponding VF regions. Results The correlation between RNFL thickness and MS (in dB) was weaker in the PACG group (rs = 0.38, P = 0.004, pseudo R2 = 0.17) than in the POAG group (rs = 0.51, P <0.001, pseudo R2 = 0.31), but the difference in the magnitude of correlation was not significant (P = 0.42).With Bonferroni correction, the structure-function correlation was significant in the superotemporal (rs = 0.62), superonasal (rs = 0.56), inferonasal (rs = 0.53), and inferotemporal (rs = 0.50) sectors in the POAG group (all P <0.001), while it was significant only in the superotemporal (rs = 0.53) and inferotemporal (rs = 0.48) sectors in the PACG group (both P <0.001). The results were similar when MS was expressed as 1/L scale. Conclusions Both POAG and PACG eyes had moderate structure-function correlations using SLP. Compared to eyes with POAG, fewer RNFL sectors have significant structure-function correlations in eyes with PACG. PMID:20202618

Interocular asymmetry of the visual field defects in newly diagnosed normal-tension glaucoma, primary open-angle glaucoma, and chronic angle-closure glaucoma.

PubMed

Huang, Ping; Shi, Yan; Wang, Xin; Liu, Mugen; Zhang, Chun

2014-09-01

To compare the interocular asymmetry of visual field loss in newly diagnosed normal-tension glaucoma (NTG), primary open-angle glaucoma (POAG), and chronic angle-closure glaucoma (CACG) patients. Visual field results of 117 newly diagnosed, treatment-naive glaucoma patients (42 NTG, 38 POAG, and 37 CACG) were studied retrospectively. The following 3 visual field defect parameters were used to evaluate the interocular asymmetry: (1) global indices; (2) local mean deviations (MDs) of 6 predefined visual field areas; and (3) stage designated by glaucoma staging system 2. The differences of the above parameters between the trial eye (the eye with greater MDs) and the fellow eye in each subject were defined as interocular asymmetry scores. Interocular asymmetry of visual field loss was presented in all the 3 groups (all P<0.05). CACG group had greater total MD interocular asymmetry score compared with the NTG and POAG groups (among groups, P=0.008; NTG vs. CACG, P=0.005; POAG vs. CACG, P=0.009). CACG also presented with significantly higher local MD interocular asymmetry scores at central, inferior, and temporal areas compared with those of the POAG group and at inferior area compared with that of NTG group. No significant difference in either total or local MDs was detected between NTG and POAG (all P>0.05). Interocular asymmetry scores of glaucoma staging system 2 had no significant difference among the 3 groups (P=0.068). All CACG, POAG, and NTG groups presented with interocular asymmetric visual field loss at the time of diagnosis. CACG had greater interocular asymmetry compared with NTG and POAG. No significant interocular asymmetry difference was observed between NTG and POAG.

Distinct iris gene expression profiles of primary angle closure glaucoma and primary open angle glaucoma and their interaction with ocular biometric parameters.

PubMed

Seet, Li-Fong; Narayanaswamy, Arun; Finger, Sharon N; Htoon, Hla M; Nongpiur, Monisha E; Toh, Li Zhen; Ho, Henrietta; Perera, Shamira A; Wong, Tina T

2016-11-01

This study aimed to evaluate differences in iris gene expression profiles between primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) and their interaction with biometric characteristics. Prospective study. Thirty-five subjects with PACG and thirty-three subjects with POAG who required trabeculectomy were enrolled at the Singapore National Eye Centre, Singapore. Iris specimens, obtained by iridectomy, were analysed by real-time polymerase chain reaction for expression of type I collagen, vascular endothelial growth factor (VEGF)-A, -B and -C, as well as VEGF receptors (VEGFRs) 1 and 2. Anterior segment optical coherence tomography (ASOCT) imaging for biometric parameters, including anterior chamber depth (ACD), anterior chamber volume (ACV) and lens vault (LV), was also performed pre-operatively. Relative mRNA levels between PACG and POAG irises, biometric measurements, discriminant analyses using genes and biometric parameters. COL1A1, VEGFB, VEGFC and VEGFR2 mRNA expression was higher in PACG compared to POAG irises. LV, ACD and ACV were significantly different between the two subgroups. Discriminant analyses based on gene expression, biometric parameters or a combination of both gene expression and biometrics (LV and ACV), correctly classified 94.1%, 85.3% and 94.1% of the original PACG and POAG cases, respectively. The discriminant function combining genes and biometrics demonstrated the highest accuracy in cross-validated classification of the two glaucoma subtypes. Distinct iris gene expression supports the pathophysiological differences that exist between PACG and POAG. Biometric parameters can combine with iris gene expression to more accurately define PACG from POAG. © 2016 The Authors. Clinical & Experimental Ophthalmology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Ophthalmologists.

Impact of Socioeconomic Status on the Diagnosis of Primary Open-Angle Glaucoma and Primary Angle Closure Glaucoma: A Nationwide Population-Based Study in Taiwan.

PubMed

Ko, Yu-Chieh; Hwang, De-Kuang; Chen, Wei-Ta; Lee, Ching-Chih; Liu, Catherine J

2016-01-01

To understand the impact of socioeconomic status (SES) on the diagnosis of primary open-angle glaucoma (POAG) and primary angle closure glaucoma (PACG) in Taiwan. Subjects with glaucoma were identified from the National Health Insurance Research Database of year 2006, which included one million randomly selected insurants. Individuals who had ≥4 ambulatory visits within one year which had the diagnosis code of POAG (ICD-9-CM 365.11 or 365.12) or PACG (365.23) and concurrent prescription of anti-glaucoma medication or surgery were selected. Individual SES was represented by monthly income calculated from the insurance premium. Neighborhood SES was defined based on neighborhood household income averages. Urbanization level of habitation was categorized into 3 levels. The odds ratio of having POAG or PACG in subjects with different SES was evaluated by using multiple logistic regression analysis. In total, 752 and 561 subjects with POAG and PACG, respectively, who were treated on a regular basis, were identified. The diagnosis of glaucoma was affected by age, gender, frequency of healthcare utilization, individual SES, and urbanization level of habitation. With the adjustment of age, gender, healthcare utilization, neighborhood SES and level of urbanization, subjects with lower income were more likely to be diagnosed as PACG, but less likely as POAG. Subjects with more frequent healthcare utilization were more likely to be diagnosed with glaucoma. Subjects with low SES were more susceptible to PACG, but subjects with high SES were more likely to be diagnosed as POAG. This information is useful for the design and target participant setting in glaucoma education and screening campaign to maximize the efficacy of limited resources in preventing glaucoma blindness.

[Chamber Angle Assessment in Clinical Practice - A Comparison between Optical Coherence Tomography and Gonioscopy].

PubMed

Mösler, M P; Werner, J U; Lang, G K

2015-07-01

In glaucoma the structures of the anterior chamber are important for classification, therapy, progression and prognosis. In this context anterior segment optical coherence tomography (AS-OCT) gains more relevance. This study compares AS-OCT with gonioscopy in diagnostic performance of chamber angle (CA) assessment. 104 consecutive subjects with glaucoma underwent AS-OCT imaging using the Visante OCT. RESULTS were compared to gonioscopic grading from patient history using the Shaffer system. In addition, anterior chamber depth (ACD) assessment using slitlamp examination was evaluated as a prognostic factor for chamber angle width (CAW) and verified by AS-OCT measurement. Average CAW was 29° (AS-OCT). 17 % of the CAs that were "wide" in gonioscopy (variance 5-55°), showed a "narrow" CA in AS-OCT. 35 % of the CAs that were "narrow" in gonioscopy (variance 0-39°) showed a "wide" CA in AS-OCT. ACD assessment using slitlamp examination is a good predictor for CAW. In this context the technique provides equal informative value as gonioscopy. In cases of "wide" ACDs it is even superior. The critical ACD for an increased risk of angle closure is 2.4 mm. Concerning the critical ACD (< 2.4 mm) the technique gave the possibility to estimate, whether the patients were in the crucial range or not. Average ACD was 2.7 mm (AS-OCT). A strong correlation (correlation coefficient 0.83) between ACD and CAW was observed. Variation of 1 mm in the ACD leads to a change of 18.9° in the CAW. All patients with angle closure glaucoma were below this threshold and 74 % of patients with critical ACD had "narrow" (AS-OCT) CAs. In the case of routine clinical practice with inexperienced residents or circumstances that make gonioscopy difficult or impossible, optical coherence tomography is an effective alternative to the gold standard and is to some extent even superior. Georg Thieme Verlag KG Stuttgart · New York.

High prevalence of narrow angles among Chinese-American glaucoma and glaucoma suspect patients.

PubMed

Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data were collected for sex, age, race (self-declared), refraction (spherical equivalent), intraocular pressure, gonioscopy, and vertical cup-to-disk ratio. Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade < or = 2 in 3 or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the 2 groups did not differ in terms of sex, refraction, intraocular pressure, or cup-to-disk ratio (all, P > or = 0.071). In a multivariate model including age, sex, and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of sex or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed.

One-stage closure of isolated cleft palate with the Veau-Wardill-Kilner V to Y pushback procedure or the Cronin modification. III. Comparison of lateral craniofacial morphology.

PubMed

Heliövaara, A; Ranta, R

1993-10-01

The craniofacial morphology of 116 consecutive patients with isolated cleft palate was studied by means of lateral cephalograms at 17 to 20 years of age. One-stage hard- and soft-palate closure had been carried out at the mean age of 1.8 years by using the Veau-Wardill-Kilner or the Cronin mucoperiosteal palatal V-Y pushback technique. In the Veau-Wardill-Kilner group the cranial base was longer, the cranial base angle was larger, and the mandible longer and its ramus higher but less backward rotated. The patients with originally the most extensive clefts showed the most marked deviations in craniofacial morphology at adult age.

Numerical exploration of non-axisymmetric divertor closure in the small angle slot (SAS) divertor at DIII-D

NASA Astrophysics Data System (ADS)

Frerichs, Heinke; Schmitz, Oliver; Covele, Brent; Guo, Houyang; Hill, David; Feng, Yuhe

2017-10-01

In the Small Angle Slot (SAS) divertor in DIII-D, the combination of misaligned slot structure and non-axisymmetric perturbations to the magnetic field causes the strike point to vary radially along the divertor slot and even leave it at some toroidal locations. This effect essentially introduces an opening in the divertor slot from where recycling neutrals can easily escape, and thereby degrade performance of the slot divertor. This effect has been approximated by a finite gap in the divertor baffle. Simulations with EMC3-EIRENE show that a toroidally localized loss of divertor closure can result in non-axisymmetric divertor densities and temperatures. This introduces a density window of 10-15% on top of the nominal threshold separatrix density during which a non-axisymmetric onset of local detachment occurs, initially leaving the gap and up to 60 deg beyond that still attached. Conversely, the impact of such toroidally localized divertor perturbations on the toroidal symmetry of midplane separatrix conditions is small. This work has been funded by the U.S. Department of Energy under Early Career Award Grant DE-SC0013911, and Grant DE-FC02-04ER54698.

Evaluating Models of The Neutral, Barotropic Planetary Boundary Layer using Integral Measures: Part I. Overview

NASA Astrophysics Data System (ADS)

Hess, G. D.; Garratt, J. R.

Data for the cross-isobaric angle 0, the geostrophic drag coefficient Cg, and the functions A and B of Rossby number similarity theory, obtained from meteorological field experiments, are used to evaluate a range of models of the neutral, barotropic planetary boundary layer. The data give well-defined relationships for 0, Cg, and the integrated dissipation rate over the boundary layer, as a function of the surface Rossby number. Lettau's first-order closure mixing-length model gives an excellent fit to the data; other simple models give reasonable agreement. However more sophisticated models, e.g., higher-order closure, large-eddy simulation, direct numerical simulation and laboratory models, give poor fits to the data. The simplemodels have (at least) one free parameter in their turbulence closure that is matched toatmospheric observations; the more sophisticated models either base their closure onmore general flows or have no free closure parameters. It is suggested that all of theatmospheric experiments that we could locate violate the strict simplifying assumptionsof steady, homogeneous, neutral, barotropic flow required by the sophisticated models.The angle 0 is more sensitive to violations of the assumptions than is Cg.

Dual-illumination mode, wide-field probe imaging scheme for imaging irido-corneal angle region inside eye

NASA Astrophysics Data System (ADS)

Shinoj, V. K.; Murukeshan, V. M.; Hong, Jesmond; Baskaran, M.; Aung, Tin

2015-07-01

Noninvasive medical imaging techniques have generated great interest and high potential in the research and development of ocular imaging and follow up procedures. It is well known that angle closure glaucoma is one of the major ocular diseases/ conditions that causes blindness. The identification and treatment of this disease are related primarily to angle assessment techniques. In this paper, we illustrate a probe-based imaging approach to obtain the images of the angle region in eye. The proposed probe consists of a micro CCD camera and LED/NIR laser light sources and they are configured at the distal end to enable imaging of iridocorneal region inside eye. With this proposed dualmodal probe, imaging is performed in light (white visible LED ON) and dark (NIR laser light source alone) conditions and the angle region is noticeable in both cases. The imaging using NIR sources have major significance in anterior chamber imaging since it evades pupil constriction due to the bright light and thereby the artificial altering of anterior chamber angle. The proposed methodology and developed scheme are expected to find potential application in glaucoma disease detection and diagnosis.

Assessment of the anterior chamber parameters after laser iridotomy in primary angle close suspect using Pentacam and gonioscopy.

PubMed

Esmaeili, Alireza; Barazandeh, Behzad; Ahmadi, Sina; Haghi, Alireza; Ahmadi Hosseini, Seyed Mahdi; Abolbashari, Fereshteh

2013-01-01

To evaluate the changes in the anterior segment parameters of the subjects with primary angle closure suspect (PACS) before and after laser iridotomy (LI) using the Pentacam and gonioscopy. Forty-eight eyes of 48 PACS were included. Anterior chamber angle (ACA), central anterior chamber depth (ACD), anterior chamber volume (ACV) and central corneal thickness (CCT) were recorded from the Pentacam before and one month after LI. ACA was graded according to Shaffer classification using the Goldmann gonioscopy. ACA increased significantly from 25.59±4.41 to 26.46±4.33 degrees (P=0.009) and ACV changed from 85.97±16.07mm(3) to 99.25±15.83mm(3) (P=0.000). The changes in ACD, CCT and intraocular pressure were non-significant (P>0.05). Gonioscopy showed significant widening of the Shaffer angle in 4 quadrants (P<0.001). Pentacam can serve as the objective instrument in assessing the efficacy of LI.

High Prevalence of Narrow Angles among Chinese-American Glaucoma and Glaucoma Suspect Patients

PubMed Central

Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

Purpose To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Patients and Methods Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data was collected for gender, age, race (self-declared), refraction (spherical equivalent), intraocular pressure (IOP), gonioscopy and vertical cup-to-disk ratio (CDR). Results Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade ≤2 in three or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the two groups did not differ in terms of gender, refraction, IOP or CDR (all, P≥0.071). In a multivariate model including age, gender and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). Conclusions A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of gender or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed. PMID:19826385

Early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma: an economic evaluation based on data from the EAGLE trial

PubMed Central

Javanbakht, Mehdi; Azuara-Blanco, Augusto; Burr, Jennifer M; Ramsay, Craig; Cooper, David; Cochran, Claire; Norrie, John; Scotland, Graham

2017-01-01

Objective To investigate the cost-effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma (PACG) compared to standard care. Design Cost-effectiveness analysis alongside a multicentre pragmatic two-arm randomised controlled trial. Patients were followed-up for 36 months, and data on health service usage and health state utility were collected and analysed within the trial time horizon. A Markov model was developed to extrapolate the results over a 5-year and 10-year time horizon. Setting 22 hospital eye services in the UK. Population Males and females aged 50 years or over with newly diagnosed PACG or primary angle closure (PAC). Interventions Lens extraction compared to standard care (ie, laser iridotomy followed by medical therapy and glaucoma surgery). Outcome measures Costs of primary and secondary healthcare usage (UK NHS perspective), quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio (ICER) for lens extraction versus standard care. Results The mean age of participants was 67.5 (8.42), 57.5% were women, 44.6% had both eyes eligible, 1.4% were of Asian ethnicity and 35.4% had PAC. The mean health service costs were higher in patients randomised to lens extraction: £2467 vs £1486. The mean adjusted QALYs were also higher with early lens extraction: 2.602 vs 2.533. The ICER for lens extraction versus standard care was £14 284 per QALY gained at three years. Modelling suggests that the ICER may drop to £7090 per QALY gained by 5 years and that lens extraction may be cost saving by 10 years. Our results are generally robust to changes in the key input parameters and assumptions. Conclusions We find that lens extraction has a 67–89% chance of being cost-effective at 3 years and that it may be cost saving by 10 years. Trial registration number ISRCTN44464607; Results. PMID:28087548

The biometric study in different stages of primary angle-closure glaucoma

PubMed Central

Chen, Y-Y; Chen, Y-Y; Sheu, S-J; Chou, P

2013-01-01

Purpose This study compared the general and ocular biometric characteristics of normal, primary angle closure (PAC), and primary angle-closure glaucoma (PACG) patients to better understand the possible relationship between differences in ocular parameters that might predict risk for PACG in PAC patients. Methods One hundred normal, 90 PAC, and 90 PACG eyes were retrospectively reviewed. General characteristics such as age, gender, body height, body weight, blood pressure, pulse, systemic diseases, and education level were recorded. Ocular findings included visual acuity, intraocular pressure, refraction, cup to disc ratio, and ocular biometry. Ocular biometry was obtained by A-scan ultrasonography (Digital A/B scan 5500; Sonomed Inc., Lake Success, NY, USA). The parameters recorded were anterior chamber depth (ACD), lens thickness (LT), axial length (AXL), lens/axial length factor (LAF), and relative lens position (RLP). Results Although the controls, PAC group, and PACG group were found to be significantly different in age (62.7±9.8; 65.3±7.5; and 66.0±7.4, respectively), there were no gender differences. With regard to ocular parameters, the ACD tended to decrease and the LT and LAF tended to increase from normal to PAC to PACG. The eyes of the PACG group had significantly shallower ACD (P<0.001) and thicker lens (P<0.001) than those of the PAC group. While PAC had similar lens position to the control group, PACG had more anteriorly positioned lens than the PAC group (P<0.001). Logistic regression analysis found a significant association between a decrease in ACD and increased risk of PACG (odds ratio (OR)=3.59 for 0.2 mm decrease in ACD) as well as a significant association between an increase in LT and increased risk of PACG (OR=1.30). Conclusions In addition to LT, a shallower ACD owing to a change in RLP may have a role in the progression from PAC to PACG. Owing to the differences of certain biometric characteristics between PAC and PACG, A-scan ultrasonography might potentially be used for the early detection of PACG in PAC eyes. PMID:23788204

Thermodynamically Constrained Averaging Theory (TCAT) Two-Phase Flow Model: Derivation, Closure, and Simulation Results

NASA Astrophysics Data System (ADS)

Weigand, T. M.; Miller, C. T.; Dye, A. L.; Gray, W. G.; McClure, J. E.; Rybak, I.

2015-12-01

The thermodynamically constrained averaging theory (TCAT) has been usedto formulate general classes of porous medium models, including newmodels for two-fluid-phase flow. The TCAT approach provides advantagesthat include a firm connection between the microscale, or pore scale,and the macroscale; a thermodynamically consistent basis; explicitinclusion of factors such as interfacial areas, contact angles,interfacial tension, and curvatures; and dynamics of interface movementand relaxation to an equilibrium state. In order to render the TCATmodel solvable, certain closure relations are needed to relate fluidpressure, interfacial areas, curvatures, and relaxation rates. In thiswork, we formulate and solve a TCAT-based two-fluid-phase flow model. We detail the formulation of the model, which is a specific instancefrom a hierarchy of two-fluid-phase flow models that emerge from thetheory. We show the closure problem that must be solved. Using recentresults from high-resolution microscale simulations, we advance a set ofclosure relations that produce a closed model. Lastly, we solve the model using a locally conservative numerical scheme and compare the TCAT model to the traditional model.

Effect of primary iris and ciliary body cyst on anterior chamber angle in patients with shallow anterior chamber*

PubMed Central

Wang, Bing-hong; Yao, Yu-feng

2012-01-01

Objective: To evaluate the prevalence of primary iris and/or ciliary body cysts in eyes with shallow anterior chamber and their effect on the narrowing of the anterior chamber angle. Methods: Among the general physical check-up population, subjects with shallow anterior chambers, as judged by van Herick technique, were recruited for further investigation. Ultrasound biomicroscope (UBM) was used to detect and measure the cysts located in the iris and/or ciliary body, the anterior chamber depth (ACD), the angle opening distance at 500 μm (AOD500), and the trabecular-iris angle (TIA). A-scan ultrasonography was used to measure the ocular biometry, including lens thickness, axial length, lens/axial length factor (LAF), and relative lens position (RLP). The effect of the cyst on narrowing the corresponding anterior chamber angle and the entire angle was evaluated by the UBM images, ocular biometry, and gonioscopic grading. The eye with unilateral cyst was compared with the eye without the cyst for further analysis. Results: Among the 727 subjects with shallow anterior chamber, primary iris and ciliary body cysts were detected in 250 (34.4%) patients; among them 96 (38.4%) patients showed unilateral single cyst, 21 (8.4%) patients had unilateral double cysts, and 42 (16.8%) patients manifested unilateral multiple and multi-quadrants cysts. Plateau iris configuration was found in 140 of 361 (38.8%) eyes with cysts. The mean size of total cysts was (0.6547±0.2319) mm. In evaluation of the effect of the cyst size and location on narrowing the corresponding angle to their position, the proportion of the cysts causing corresponding angle narrowing or closure among the cysts larger than 0.8 mm (113/121, 93.4%) was found to be significantly higher than that of the cysts smaller than 0.8 mm (373/801, 46.6%), and a significant higher proportion was also found in the cysts located at iridociliary sulcus (354/437, 81.0%) than in that at the pars plicata (131/484, 27.1%). In evaluating the effect of the cyst on the entire anterior chamber angle, the eyes with multiple and multi-quadrants cysts manifested significant narrowing of the entire anterior chamber angle as compared with the eyes without cysts, based on the data analysis in comparison of TIA, AOD500, and gonioscopic grading evaluation. The unilateral single or double cysts in the eyes had no significant effect on narrowing of anterior chamber angle as compared with eyes without cysts. The iris and/or ciliary body cysts did not seem to affect the axial length, ACD, lens thickness, RLP, LAF. Conclusions: The prevalence of primary iris and ciliary body cyst was 34.4% in the subjects with shallow anterior chamber. The cysts larger than 0.8 mm, locating at iridociliary sulcus, or multiple and extensive cysts were inclined to cause the angle narrowing or closure. PMID:22949363

Evaluation of the Association Between Common Genetic Variants Near the ABCA1 Gene and Primary Angle Closure Glaucoma in a Han Chinese Population.

PubMed

Luo, Huaichao; Chen, Yuhong; Ye, Zimeng; Sun, Xinghuai; Shi, Yi; Luo, Qian; Gong, Bo; Shuai, Ping; Yang, Jiyun; Zhou, Yu; Liu, Xiaoqi; Zhang, Kaijiong; Tan, Chang; Li, Yuanfeng; Lin, Ying; Yang, Zhenglin

2015-10-01

Recently, three large genome-wide association studies have identified multiple variants associated with primary open angle glaucoma (POAG) near the ABCA1 gene. Considering that POAG and primary angle closure glaucoma (PACG) share many similar clinical manifestations, the present study was conducted to investigate whether these genetic variants were also associated with PACG in a Han Chinese population. A case-control association study of 1122 cases (PACG/PAC) and 1311 normal, matched controls was undertaken. Seven single-nucleotide polymorphisms (SNPs) near the ABCA1 gene, including rs2422493, rs2487042, rs2472496, rs2472493, rs2487032, rs2472459, and rs2472519, were genotyped. Genotype and allele frequencies were assessed using χ² tests. Linkage disequilibrium (LD) structure was analyzed by computer software. Among the SNPs genotyped, no association was observed between these SNPs and PACG. However, we discovered that two haplotypes, CATTTAC (corrected P = 0.048) and CGCCCGC (corrected P = 0.048), remained significantly associated with PACG/PAC after Bonferroni correction. Subjects with the CATTTAC haplotype have a 1.71-fold increased possibility of having PACG/PAC, whereas subjects with the CGCCCGC haplotype have 0.47-fold decreased possibility of developing PACG. Our findings suggest that the genetic backgrounds of PACG and POAG might be different. However, whether or not ABCA1 plays a role in the development of PACG is still not made certain by this study. Thus, further research is needed to find the role of ABCA1 in the progress of PACG.

Quantitative analysis of iris changes after physiologic and pharmacologic mydriasis in a rural Chinese population.

PubMed

Zhang, Ye; Li, Si Zhen; Li, Lei; He, Ming Guang; Thomas, Ravi; Wang, Ning Li

2014-04-24

To estimate and compare the change in iris cross-sectional area (IA) and iris volume (IV) following physiologic and pharmacologic pupil dilation in primary angle closure suspects (PACS) and normal subjects. Anterior segment-optical coherence tomography (AS-OCT) measurements in light, dark, and following pharmacologic dilation were obtained on 186 PACS and 224 normal subjects examined during the 5-year follow-up of the Handan Eye Study. Iris cross-sectional area, IV, and other biometric parameters calculated using the Zhongshan angle assessment program in the right eyes of all subjects were analyzed. The mean IA and IV decreased in dark compared with light and after pharmacologic dilation in both PACS and normal eyes. This change was statistically significant in normal eyes: light versus pharmacologic dilation for IA (P = 0.038) and for IV, both light versus dark (P = 0.031) and light versus pharmacologic dilation (P = 0.012). A longer axial length (P = 0.028) and a greater change in pupil diameter (PD) (P < 0.001) were associated with a larger decrease of IA for the light to dark comparison. A diagnosis of normal eyes (P = 0.011), larger PD in dark (P = 0.001), and a larger change in PD (P = 0.001) were associated with a larger decrease of IV from light to dark. The differences in iris behavior between PACS and normal rural Chinese subjects following physiologic or pharmacologic pupillary dilation may help provide insights into the pathogenesis of angle closure. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

[Acute angle-closure glaucoma after total hip replacement surgery].

PubMed

Ujino, H; Morimoto, O; Yukioka, H; Fujimori, M

1997-06-01

Acute angle-closure glaucoma is a rare complication of surgery. We experienced a case of postoperative acute glaucoma after total hip replacement under general anesthesia. A 49-year-old female without signs or symptoms of glaucoma was premedicated with the intramuscular administration of secobarbital, atropine and ranitidine. Following rapid induction with thiopental and vecuronium, anesthesia was maintained with N2O-O2-sevoflurane. PGE1 was administered intravenously for induced hypotension during the surgery. Hemorrhagic shock with a systolic blood pressure of 60 mmHg continued for 15 min during the surgery. Large amounts of fluid and ephedrine were required for treating this hypotensive episode. Vecuronium was reversed by bolus injection of neostigmine and atropine at the end of surgery. Soon after recovery from anesthesia, she complained of pain and blurred vision in her both eyes. The consulting ophthalmologist made a diagnosis of acute glaucoma due to high intraocular pressure (IOP). Treatment with glycerol and pilocarpine had no effect on the elevated IOP. The laser iridotomy performed on her at 5th and 7th post-operative days improved her vision completely. The post-operative glaucoma may cause serious permanent loss of vision. An early diagnosis of this post-operative complication and its treatment with drugs and surgery should be emphasized.

Rates of hospital admissions for primary angle closure glaucoma among Chinese, Malays, and Indians in Singapore

PubMed Central

Wong, T. Y.; Foster, P.; Seah, S.; Chew, P.

2000-01-01

AIM—To estimate the rates of hospital admissions for primary angle closure glaucoma (PACG) in Chinese, Malays, and Indians in Singapore
METHODS—A population-wide hospital discharge database in Singapore was used to identify all hospital admissions with a primary discharge diagnosis of PACG (International Classification of Disease—CM code: 365.2). The Singapore census was used for denominator data.
RESULTS—Between 1993 and 1997 there were 894 hospital admissions for PACG. The mean annual rate of PACG admissions was 11.1 per 100 000 (95% confidence interval (CI), 10.4, 11.8) among people aged 30 years and over. The annual rate was highest for Chinese (age and sex adjusted rate: 12.2 per 100 000), which was twice that of Malays (6.0 per 100 000) and Indians (6.3 per 100 000). Females had two times higher rates than males in all three races (age adjusted relative risk: 2.0, 95% CI: 1.7, 2.3).
CONCLUSION—Malay and Indian people had identical rates of hospital admissions for PACG, which were only half the rates compared with Chinese.

 PMID:10966951

The early history of glaucoma: the glaucous eye (800 BC to 1050 AD)

PubMed Central

Leffler, Christopher T; Schwartz, Stephen G; Hadi, Tamer M; Salman, Ali; Vasuki, Vivek

2015-01-01

To the ancient Greeks, glaukos occasionally described diseased eyes, but more typically described healthy irides, which were glaucous (light blue, gray, or green). During the Hippocratic period, a pathologic glaukos pupil indicated a media opacity that was not dark. Although not emphasized by present-day ophthalmologists, the pupil in acute angle closure may appear somewhat green, as the mid-dilated pupil exposes the cataractous lens. The ancient Greeks would probably have described a (normal) green iris or (diseased) green pupil as glaukos. During the early Common Era, eye pain, a glaucous hue, pupil irregularities, and absence of light perception indicated a poor prognosis with couching. Galen associated the glaucous hue with a large, anterior, or hard crystalline lens. Medieval Arabic authors translated glaukos as zarqaa, which also commonly described light irides. Ibn Sina (otherwise known as Avicenna) wrote that the zarqaa hue could occur due to anterior prominence of the lens and could occur in an acquired manner. The disease defined by the glaucous pupil in antiquity is ultimately indeterminate, as the complete syndrome of acute angle closure was not described. Nonetheless, it is intriguing that the glaucous pupil connoted a poor prognosis, and came to be associated with a large, anterior, or hard crystalline lens. PMID:25673972

The Seasonality of Acute Attack of Primary Angle-Closure Glaucoma in Beijing, China.

PubMed

Zhu, Jingyuan; Xu, Yang; Wang, Hongyuan; Liu, Dongjing; Zhu, Jingbo; Wu, Huijuan

2018-03-05

In this study, the seasonality of acute attack of primary angle-closure glaucoma (PACG) was analysed. This retrospective case series included 283 patients (200 women, 83 men; mean age, 68.2 ± 10.3 years; range, 37-96 years) with acute attack of PACG from a university-based clinic over 4 years. Patients' age and sex, and the date and season of onset of PACG attack, were analysed. Descriptive analysis and von Mises distribution were used for statistical analysis. The highest incidence of acute attack of PACG was observed in those aged 60-69 years (34.6%). Descriptive analysis showed that the incidence was greater in June and July for men, November for women, and November for the entire sample. An angular plot (using von Mises distribution) of the individual dates of onset revealed the estimated peak onset on September 11, November 8, and October 28 for men, women, and both, respectively. Integration of the results from the two analyses revealed the incidence to be higher in the summer and winter for men, and in the winter for women and for the entire sample. More females than males were affected. Monthly and seasonal variations in onset were observed, which might be related to weather changes.

Structure-function correlations using scanning laser polarimetry in primary angle-closure glaucoma and primary open-angle glaucoma.

PubMed

Lee, Pei-Jung; Liu, Catherine Jui-Ling; Wojciechowski, Robert; Bailey-Wilson, Joan E; Cheng, Ching-Yu

2010-05-01

To assess the correlations between retinal nerve fiber layer (RNFL) thickness measured with scanning laser polarimetry and visual field (VF) sensitivity in primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Prospective, comparative, observational cases series. Fifty patients with POAG and 56 patients with PACG were examined using scanning laser polarimetry with variable corneal compensation (GDx VCC; Laser Diagnostic Technologies, Inc.) and Humphrey VF analyzer (Carl Zeiss Meditec, Inc.) between August 2005 and July 2006 at Taipei Veterans General Hospital. Correlations between RNFL thickness and VF sensitivity, expressed as mean sensitivity in both decibel and 1/Lambert scales, were estimated by the Spearman rank correlation coefficient (r(s)) and multivariate median regression models (pseudo R(2)). The correlations were determined globally and for 6 RNFL sectors and their corresponding VF regions. The correlation between RNFL thickness and mean sensitivity (in decibels) was weaker in the PACG group (r(s) = 0.38; P = .004; pseudo R(2) = 0.17) than in the POAG group (r(s) = 0.51; P < .001; pseudo R(2) = .31), but the difference in the magnitude of correlation was not significant (P = .42). With Bonferroni correction, the structure-function correlation was significant in the superotemporal (r(s) = 0.62), superonasal (r(s) = 0.56), inferonasal (r(s) = 0.53), and inferotemporal (r(s) = 0.50) sectors in the POAG group (all P < .001), whereas it was significant only in the superotemporal (r(s) = 0.53) and inferotemporal (r(s) = 0.48) sectors in the PACG group (both P < .001). The results were similar when mean sensitivity was expressed as 1/Lambert scale. Both POAG and PACG eyes had moderate structure-function correlations using scanning laser polarimetry. Compared with eyes with POAG, fewer RNFL sectors have significant structure-function correlations in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

Diagnostic ability of peripapillary vessel density measurements of optical coherence tomography angiography in primary open-angle and angle-closure glaucoma.

PubMed

Rao, Harsha L; Kadambi, Sujatha V; Weinreb, Robert N; Puttaiah, Narendra K; Pradhan, Zia S; Rao, Dhanaraj A S; Kumar, Rajesh S; Webers, Carroll A B; Shetty, Rohit

2017-08-01

To evaluate the diagnostic ability of peripapillary vessel density measurements on optical coherence tomography angiography (OCTA) in primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG), and to compare these with peripapillary retinal nerve fibre layer (RNFL) thickness measurements. In a cross-sectional study, 48 eyes of 33 healthy control subjects, 63 eyes of 39 patients with POAG and 49 eyes of 32 patients with PACG underwent OCTA (RTVue-XR, Optovue, Fremont, California, USA) and RNFL imaging with spectral domain OCT. Diagnostic abilities of vessel density and RNFL parameters were evaluated using area under receiver operating characteristic curves (AUC) and sensitivities at fixed specificities. AUCs of peripapillary vessel density ranged between 0.48 for the temporal sector and 0.88 for the inferotemporal sector in POAG. The same in PACG ranged between 0.57 and 0.86. Sensitivities at 95% specificity ranged from 13% to 70% in POAG, and from 10% to 67% in PACG. AUCs of peripapillary RNFL thickness ranged between 0.51 for the temporal sector and 0.91 for the inferonasal sector in POAG. The same in PACG ranged between 0.61 and 0.87. Sensitivities at 95% specificity ranged from 8% to 68% in POAG, and from 2% to 67% in PACG. AUCs of all peripapillary vessel density measurements were comparable (p>0.05) to the corresponding RNFL thickness measurements in both POAG and PACG. Diagnostic ability of peripapillary vessel density parameters of OCTA, especially the inferotemporal sector measurement, was good in POAG and PACG. Diagnostic abilities of vessel density measurements were comparable to RNFL measurements in both POAG and PACG. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Cost-effectiveness of community screening for glaucoma in rural India: a decision analytical model.

PubMed

John, D; Parikh, R

2018-02-01

Studies in several countries have demonstrated the cost-effectiveness of population-based screening for glaucoma when targeted at high-risk groups such as older adults and with familial history of disease. This study conducts a cost-effective analysis of a hypothetical community screening and subsequent treatment programme in comparison to opportunistic case finding for glaucoma in rural India. A hypothetical screening programme for both primary open-angle glaucoma and angle-closure disease was built for a population aged between 40 and 69 years in rural areas of India. A decision analytical model was built to model events, costs and treatment pathways with and without a hypothetical screening programme for glaucoma for a rural-based population aged between 40 and 69 years in India. The treatment pathway included both primary open-angle glaucoma and angle-closure disease. The data on costs of screening and treatment were provided by an administrator of a tertiary eye hospital in Eastern India. The probabilities for the screening and treatment pathway were derived from published literature and a glaucoma specialist. The glaucoma prevalence rates were adapted from the Chennai Glaucoma Study findings. An incremental cost-effectiveness ratio value of ₹7292.30 per quality-adjusted life-year was calculated for a community-screening programme for glaucoma in rural India. The community screening for glaucoma would treat an additional 2872 cases and prevent 2190 person-years of blindness over a 10-year period. Community screening for glaucoma in rural India appears to be cost-effective when judged by a ratio of willingness-to-pay thresholds as per WHO-CHOICE guidelines. For community screening to be cost-effective, adequate resources, such as trained medical personnel and equipment would need to be made available. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Uveal effusion following acute primary angle-closure: a retrospective case series

PubMed Central

Yang, Jian-Gang; Li, Jian-Jun; Tian, Hua; Li, Yan-Hong; Gong, Yu-Jing; Su, An-Le; He, Na

2017-01-01

AIM To evaluate the morphological changes in anterior segment in Chinese patients with uveal effusion (UE) after the attack of acute primary angle-closure (APAC) using ultrasound biomicroscopy (UBM), and to assess the clinical course and prognosis of the disease. METHODS In a retrospective case series, 26 eyes in 26 consecutive patients diagnosed with UE after the treatment of intraocular pressure (IOP)-lowering medication for the attack of APAC were enrolled. The unaffected fellow eyes served as controls. The morphological changes were observed by ultrasonography, slit lamp microscopy and gonioscopy. UBM was used to assess the degree and extent of effusion based on the analysis of parameters associated with UE. RESULTS The mean IOP was 9.2 (SD 2.1) mm Hg at the diagnosis of UE after IOP-lowering medication, while 14.1 (SD, 2.6) mm Hg in the fellow eyes (P=0.000). The anterior chamber depth (ACD) (P=0.000), angle opening distance at 500 µm (AOD500) (P<0.01) and anterior chamber angle (ACA) (P<0.05) were decreased significantly, while ciliary body thickness (CBT) (P<0.05) increased significantly in UE eyes. UE grade analysis showed 7 eyes in grade 1, 9 eyes in grade 2, and 10 eyes in grade 3. Quadrant scores were performed of 4 eyes in 1 quadrant, 3 eyes in 3 quadrants, and 19 eyes in 4 quadrants. There was the positive correlation between grade and quadrant score (r=0.644, P=0.000). The effusion on all eyes were recovered after medication, which mean IOP was 13.9 (SD, 2.8) mm Hg. CONCLUSION UE is a frequent complication in Chinese patients after the attack of APAC, partially associated with hypotony. The severity of UE is correlation with height of effusion, extent of detachment, and shallower ACD. PMID:28393032

Head loss coefficient through sharp-edged orifices

NASA Astrophysics Data System (ADS)

Adam, Nicolas J.; De Cesare, Giovanni; Schleiss, Anton J.; Richard, Sylvain; Muench-Alligné, Cécile

2016-11-01

Nowadays, high-head power plants could increase their installed power capacity for many reasons, e.g. dam heightening, increase of their peak power capacity or refurbishment with new turbines. Frequently, due to several considerations, e.g. topographical or economical limitations, the existing surge tank cannot be extended to keep previous safety levels and efficiency. A valuable way to adapt these surge tanks is to place a throttle at their entrance like, for example, an orifice. The main effect of this adaptation is the introduction of head losses that reduce the extreme levels in the surge tank due to the mass oscillations resulting from a closure or opening of downstream discharge control. This research studies the influence of the edge angle of a ASME-standard orifice on the head losses. This angle introduces an asymmetrical behavior and influences head losses. Different angles are tested from 0° to the 67° (biggest angle possible for this configuration). The first step of this study is to determine experimentally the steady losses produced by orifice for several discharges. In the second step, a numerical model on ANSYS CFX is performed. Combining the two approaches, it is possible to understand and quantify the effect of the edge angle.

A cam deformity is gradually acquired during skeletal maturation in adolescent and young male soccer players: a prospective study with minimum 2-year follow-up.

PubMed

Agricola, Rintje; Heijboer, Marinus P; Ginai, Abida Z; Roels, Pauline; Zadpoor, Amir A; Verhaar, Jan A N; Weinans, Harrie; Waarsing, Jan H

2014-04-01

A cam deformity is a major risk factor for hip osteoarthritis, and its formation is thought to be influenced by high-impact sporting activities during growth. To (1) prospectively study whether a cam deformity can evolve over time in adolescents and whether its formation only occurs during skeletal maturation and (2) examine whether clinical or radiographic features can predict the formation of a cam deformity. Cohort study (prognosis); Level of evidence, 2. Preprofessional soccer players (N = 63; mean age, 14.43 years; range, 12-19 years) participated both at baseline and follow-up (mean follow-up, 2.4 ± 0.06 years). At both time points, standardized anteroposterior and frog-leg lateral radiographs were obtained. For each hip, the α angle was measured, and the anterosuperior head-neck junction was classified by a 3-point visual system as normal, flattened, or having a prominence. Differences between baseline and follow-up values for the α angle and the prevalence of each visual hip classification were calculated. Additionally, the amount of internal hip rotation, growth plate extension into the neck, and neck shaft angle were determined. Overall, there was a significant increase in the prevalence of a cam deformity during follow-up. In boys aged 12 and 13 years at baseline, the prevalence of a flattened head-neck junction increased significantly during follow-up (13.6% to 50.0%; P = .002). In all hips with an open growth plate at baseline, the prevalence of a prominence increased from 2.1% to 17.7% (P = .002). After closure of the proximal femoral growth plate, there was no significant increase in the prevalence or increase in severity of a cam deformity. The α angle increased significantly from 59.4° at baseline to 61.3° at follow-up (P = .018). The amount of growth plate extension was significantly associated with the α angle and hip classification (P = .001). A small neck shaft angle and limited internal rotation were associated with cam deformities and could also significantly predict the formation of cam deformities (α angle >60°) at follow-up. In youth soccer players, cam deformities gradually develop during skeletal maturation and are probably stable from the time of growth plate closure. The formation of a cam deformity might be prevented by adjusting athletic activities during a small period of skeletal growth, which will have a major effect on the prevalence of hip osteoarthritis.

Ocular Features of Cerebro-Costo-Mandibular Syndrome.

PubMed

Hameed, Zoya; Taylor, Simon; Lindfield, Dan

2018-01-01

Cerebro-costo-mandibular syndrome (CCMS) is a rare hereditary disorder characterized by micrognathia, posterior rib gaps, and secondary developmental delay. Patients often require ventilation and feeding support throughout life. We describe the first reported ophthalmic findings of CCMS and propose that defects in choroidal permeability lead to chronic macular edema and refractory aqueous misdirection syndrome. Here we discuss the medical and surgical management concerns of recurrent angle closure and raised intraocular pressure in a CCMS patient.

Comparison of factors associated with occludable angle between american Caucasians and ethnic Chinese.

PubMed

Wang, Ye Elaine; Li, Yingjie; Wang, Dandan; He, Mingguang; Lin, Shan

2013-11-21

To determine if factors associated with gonioscopy-determined occludable angle among American Caucasians are similar to those found in ethnic Chinese. This is a prospective cross-sectional study with 120 American Caucasian, 116 American Chinese, and 116 mainland Chinese subjects. All three groups were matched for sex and age (40-80 years). Gonioscopy was performed for each subject (occludable angles = posterior trabecular meshwork not visible for ≥2 quadrants). Anterior segment optical coherence tomography and customized software was used to measure anterior segment biometry and iris parameters, including anterior chamber depth/width (ACD, ACW), lens vault (LV), and iris thickness/area/curvature. In both Chinese and Caucasians, eyes with occludable angles had smaller ACD and ACW, and larger LV and iris curvature than eyes with open angles (all P < 0.005). Chinese eyes had smaller ACD and ACW than Caucasian eyes (both P < 0.01) in the occludable angle cohort. Iris characteristics did not differ significantly between Chinese and Caucasians in the occludable angle cohort. Based on multivariate logistic regression, gonioscopy-determined occludable angle was significantly associated with LV, iris area, and sex (all P < 0.03) in Chinese; and with LV, ACD, iris thickness, age, and sex (all P < 0.04) in Caucasians. Several factors associated with occludable angle differed between Caucasians and Chinese, suggesting potentially different mechanisms in occludable angle development in the two racial groups. This is the first study to demonstrate that lens vault is an important anterior segment optical coherence tomography parameter in the screening for angle closure in Caucasians. In addition, iris thickness was a significant predictor for occludable angles in Caucasians but was not in ethnic Chinese.

Comparison of Factors Associated With Occludable Angle Between American Caucasians and Ethnic Chinese

PubMed Central

Wang, Ye Elaine; Li, Yingjie; Wang, Dandan; He, Mingguang; Lin, Shan

2013-01-01

Purpose. To determine if factors associated with gonioscopy-determined occludable angle among American Caucasians are similar to those found in ethnic Chinese. Methods. This is a prospective cross-sectional study with 120 American Caucasian, 116 American Chinese, and 116 mainland Chinese subjects. All three groups were matched for sex and age (40–80 years). Gonioscopy was performed for each subject (occludable angles = posterior trabecular meshwork not visible for ≥2 quadrants). Anterior segment optical coherence tomography and customized software was used to measure anterior segment biometry and iris parameters, including anterior chamber depth/width (ACD, ACW), lens vault (LV), and iris thickness/area/curvature. Results. In both Chinese and Caucasians, eyes with occludable angles had smaller ACD and ACW, and larger LV and iris curvature than eyes with open angles (all P < 0.005). Chinese eyes had smaller ACD and ACW than Caucasian eyes (both P < 0.01) in the occludable angle cohort. Iris characteristics did not differ significantly between Chinese and Caucasians in the occludable angle cohort. Based on multivariate logistic regression, gonioscopy-determined occludable angle was significantly associated with LV, iris area, and sex (all P < 0.03) in Chinese; and with LV, ACD, iris thickness, age, and sex (all P < 0.04) in Caucasians. Conclusions. Several factors associated with occludable angle differed between Caucasians and Chinese, suggesting potentially different mechanisms in occludable angle development in the two racial groups. This is the first study to demonstrate that lens vault is an important anterior segment optical coherence tomography parameter in the screening for angle closure in Caucasians. In addition, iris thickness was a significant predictor for occludable angles in Caucasians but was not in ethnic Chinese. PMID:24168992

PLATEAU IRIS--DIAGNOSIS AND TREATMENT.

PubMed

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Relevant publications on plateau iris that were published until 2014. Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty.

Simulation of Two-Phase Flow Based on a Thermodynamically Constrained Averaging Theory Flow Model

NASA Astrophysics Data System (ADS)

Weigand, T. M.; Dye, A. L.; McClure, J. E.; Farthing, M. W.; Gray, W. G.; Miller, C. T.

2014-12-01

The thermodynamically constrained averaging theory (TCAT) has been used to formulate general classes of porous medium models, including new models for two-fluid-phase flow. The TCAT approach provides advantages that include a firm connection between the microscale, or pore scale, and the macroscale; a thermodynamically consistent basis; explicit inclusion of factors such as interfacial areas, contact angles, interfacial tension, and curvatures; and dynamics of interface movement and relaxation to an equilibrium state. In order to render the TCAT model solvable, certain closure relations are needed to relate fluid pressure, interfacial areas, curvatures, and relaxation rates. In this work, we formulate and solve a TCAT-based two-fluid-phase flow model. We detail the formulation of the model, which is a specific instance from a hierarchy of two-fluid-phase flow models that emerge from the theory. We show the closure problem that must be solved. Using recent results from high-resolution microscale simulations, we advance a set of closure relations that produce a closed model. Lastly, we use locally conservative spatial discretization and higher order temporal discretization methods to approximate the solution to this new model and compare the solution to the traditional model.

Multistep Approach for Improved Aesthetic and Functional Outcomes for Lower Extremity Wound Closure After Mohs Micrographic Surgery.

PubMed

Kiwanuka, Elizabeth; Cruz, Antonio P

2017-05-01

Lower extremity wounds present a major clinical challenge. This paper introduces a new multistep approach for improved aesthetic and functional outcome for lower extremity wound closure after Mohs micrographic surgery. In this prospective case series, 12 consecutive patients undergoing Mohs micrographic surgery for cutaneous malignancies of the lower extremities underwent closure assisted by elastic bandages, proper positioning with 45° flexion of the knee, buried vertical mattress sutures, and careful eversion, using a premium angled stapler. Assessment of cosmetic outcome was performed by 2 blinded observers, using the Hollander Wound Evaluation Scale. The mean age was 73 ± 9 years with most patients having at least one comorbidity. Six patients (50%) underwent resection of a basal cell carcinoma and 5 patients (42%) underwent resection of a squamous cell carcinoma and 1 patient (8%) underwent resection of a keratoacanthomatous carcinoma. There were no wound complications, and at the 3- to 6-month follow-up, 11 of the 12 wounds (92%) had an optimal Hollander Wound Evaluation Scale score of 6. This new approach to lower extremity wounds provides excellent cosmetic outcome with no reported complications.

Orthodontic space closure without contralateral extraction through mesial movement of lower molars in patients with aplastic lower second premolars.

PubMed

Zimmer, B; Guitard, Y

2001-09-01

A method is presented that allows unilateral space closure in patients with aplastic lower second premolars. Based on a straight-wire appliance, space closure was achieved with a combination of "push mechanics" using the second molar as an anchorage unit and Class II "pull mechanics", thus avoiding the application of any distalizing force on the lower incisors. The results from 13 consecutively treated subjects (five boys, eight girls, mean age 12 years and 6 months) were analyzed. Complete bodily space closure was achieved in all 13 cases within a mean treatment time of 2 years and 7 months. The desired Angle Class III molar relationship of one premolar width (+/- 1/4 premolar width) on the aplastic side was successful in eleven patients, an additional 4.7 mm of space being created for the third molar on the aplastic side compared with the contralateral side (p < or = 0.01). However, adverse effects could be kept to a minimum, with no method-dependent side effects being recorded with regard to canine and molar relationships on the contralateral side, or to overbite, overjet, or upper and lower incisor inclination. The mean lower midline shift of 0.8 mm was in accordance with the mean distal canine relationship of 1/3 premolar width on the aplastic side. These results confirm that orthodontic space closure in cases of unilateral aplastic lower second premolars can be performed successfully with the presented treatment method without the need for additional premolar extractions, prosthodontic treatment or implants. Furthermore, the prognosis for the lower wisdom tooth on the aplastic side is improved.

Incidence of secondary glaucoma in behcet disease.

PubMed

Elgin, Ufuk; Berker, Nilufer; Batman, Aygen

2004-12-01

To determine the incidence of secondary glaucoma in Behcet disease. A total of 230 eyes of 129 patients with Behcet disease, were examined in uveitis and glaucoma clinics of Ankara Social Security Eye Hospital between January 1997 and September 2002. The data from all patients were investigated both retrospectively and prospectively. The mean age of 129 patients was 34.2 +/- 7.4 years (range, 18 to 55 years). In 22 patients (17%), the disease was diagnosed on the basis of the ocular findings, while in the remaining 107 patients (83%), the period between the diagnosis of Behcet disease and the onset of the ocular symptoms was 23.3 +/- 17 months (range, 1 month to 5.3 years); 122 eyes (53%) had the episodes of acute recurrent iridocyclitis, while 108 eyes (47%) developed chronic posterior uveitis, including vitreitis, retinitis, vasculitis, or optic nerve involvement. Secondary glaucoma was diagnosed in 25 eyes (10.9%); 11 eyes (44%) with steroid or inflammation induced open angle glaucoma, 6 eyes (24%) with partial angle-closure glaucoma and peripheral anterior synechiae, 5 eyes (20%) with angle closure glaucoma, peripheral anterior synechiae, and pupil block and 3 eyes (12%) with neovascular glaucoma. The treatments included YAG-laser iridotomy in 5 eyes, diode-laser cyclodestruction in 3 eyes, primary trabeculectomies with mitomycin-c in 4 eyes, secondary trabeculectomies with mitomycin-c in 2 eyes, Ahmed valve implantations in 2 eyes, and cyclocryotherapy in 3 eyes. We suggest that secondary glaucoma is a common and serious complication of Behcet disease. It develops as a result of multiple factors, generally triggered by recurrent intraocular inflammation. Early recognition and treatment of these factors have vital importance to avoid the visual morbidity.

Costs of a community-based glaucoma detection programme: analysis of the Philadelphia Glaucoma Detection and Treatment Project.

PubMed

Pizzi, Laura T; Waisbourd, Michael; Hark, Lisa; Sembhi, Harjeet; Lee, Paul; Crews, John E; Saaddine, Jinan B; Steele, Deon; Katz, L Jay

2018-02-01

Glaucoma is the foremost cause of irreversible blindness, and more than 50% of cases remain undiagnosed. Our objective was to report the costs of a glaucoma detection programme operationalised through Philadelphia community centres. The analysis was performed using a healthcare system perspective in 2013 US dollars. Costs of examination and educational workshops were captured. Measures were total programme costs, cost/case of glaucoma detected and cost/case of any ocular disease detected (including glaucoma). Diagnoses are reported at the individual level (therefore representing a diagnosis made in one or both eyes). Staff time was captured during site visits to 15 of 43 sites and included time to deliver examinations and workshops, supervision, training and travel. Staff time was converted to costs by applying wage and fringe benefit costs from the US Bureau of Labor Statistics. Non-staff costs (equipment and mileage) were collected using study logs. Participants with previously diagnosed glaucoma were excluded. 1649 participants were examined. Mean total per-participant examination time was 56 min (SD 4). Mean total examination cost/participant was $139. The cost/case of glaucoma newly identified (open-angle glaucoma, angle-closure glaucoma, glaucoma suspect, or primary angle closure) was $420 and cost/case for any ocular disease identified was $273. Glaucoma examinations delivered through this programme provided significant health benefit to hard-to-reach communities. On a per-person basis, examinations were fairly low cost, though opportunities exist to improve efficiency. Findings serve as an important benchmark for planning future community-based glaucoma examination programmes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Interplay of spherical closed shells and N /Z asymmetry in quasifission dynamics

NASA Astrophysics Data System (ADS)

Mohanto, G.; Hinde, D. J.; Banerjee, K.; Dasgupta, M.; Jeung, D. Y.; Simenel, C.; Simpson, E. C.; Wakhle, A.; Williams, E.; Carter, I. P.; Cook, K. J.; Luong, D. H.; Palshetkar, C. S.; Rafferty, D. C.

2018-05-01

Background: Quasifission (QF) has gained tremendous importance in heavy-ion nuclear physics research because of its strong influence on superheavy-element synthesis. Collisions involving closed-shell nuclei in the entrance channel are found to affect the QF reaction mechanism. Hence, it is important to improve the understanding of their effect on QF. Apart from that, some recent studies show that the difference in N /Z of reaction partners influences the reaction dynamics. Since heavier doubly magic nuclei have different N /Z than lighter doubly magic nuclei, it is important to understand the effect of N /Z mismatch as well as the effect of shell closures. Purpose: To investigate the effect of entrance-channel shell closures and N /Z asymmetry on QF. The reactions were chosen to decouple these effects from the contributions of other entrance-channel parameters. Method: Fission fragment mass-angle distributions were measured using the CUBE fission spectrometer, consisting of two large area position-sensitive multi-wire proportional counters (MWPCs), for five reactions, namely, 50Cr+208Pb , 52Cr+Pb,208206 , 54Cr+Pb,208204 . Result: Two components were observed in the measured fragment mass angle distribution, a fast mass-asymmetric quasifission and a slow mass-symmetric component having a less significant mass-angle correlation. The ratio of these components was found to depend on spherical closed shells in the entrance channel nuclei and the magnitude of the N /Z mismatch between the two reaction partners, as well as the beam energy. Conclusions: Entrance-channel spherical closed shells can enhance compound nucleus formation provided the N /Z asymmetry is small. Increase in the N /Z asymmetry is expected to destroy the effect of entrance-channel spherical closed shells, through nucleon transfer reactions.

Scanning electron microscopy of the trabecular meshwork: understanding the pathogenesis of primary angle closure glaucoma.

PubMed

Sihota, Ramanjit; Goyal, Amita; Kaur, Jasbir; Gupta, Viney; Nag, Tapas C

2012-01-01

To study ultrastructural changes of the trabecular meshwork in acute and chronic primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) eyes by scanning electron microscopy. Twenty-one trabecular meshwork surgical specimens from consecutive glaucomatous eyes after a trabeculectomy and five postmortem corneoscleral specimens were fixed immediately in Karnovsky solution. The tissues were washed in 0.1 M phosphate buffer saline, post-fixed in 1% osmium tetraoxide, dehydrated in acetone series (30-100%), dried and mounted. Normal trabecular tissue showed well-defined, thin, cylindrical uveal trabecular beams with many large spaces, overlying flatter corneoscleral beams and numerous smaller spaces. In acute PACG eyes, the trabecular meshwork showed grossly swollen, irregular trabecular endothelial cells with intercellular and occasional basal separation with few spaces. Numerous activated macrophages, leucocytes and amorphous debris were present. Chronic PACG eyes had a few, thickened posterior uveal trabecular beams visible. A homogenous deposit covered the anterior uveal trabeculae and spaces. Converging, fan-shaped trabecular beam configuration corresponded to gonioscopic areas of peripheral anterior synechiae. In POAG eyes, anterior uveal trabecular beams were thin and strap-like, while those posteriorly were wide, with a homogenous deposit covering and bridging intertrabecular spaces, especially posteriorly. Underlying corneoscleral trabecular layers and spaces were visualized in some areas. In acute PACG a marked edema of the endothelium probably contributes for the acute and marked intraocular pressure (IOP) elevation. Chronically raised IOP in chronic PACG and POAG probably results, at least in part, from decreased aqueous outflow secondary to widening and fusion of adjacent trabecular beams, together with the homogenous deposit enmeshing trabecular beams and spaces.

Quantitative and qualitative evaluation of a web-based, interactive approach for teaching the management of angle-closure glaucoma.

PubMed

Blumberg, Dana M; Quigley, Harry A; Goldberg, Harry R

2009-02-01

To construct a validated Internet-based teaching system that improves diagnostic and therapeutic skills related to glaucoma diagnosis. Nonrandomized clinical trial. Thirty-four glaucoma specialists and 21 ophthalmologists-in-training. An interactive program was designed to improve the recognition of gonioscopic findings and to manage angle-closure glaucoma (ACG) patients, including technical information in performing gonioscopy, ability to recognize angle structures, and treatment choices. The behavior of participants permitted the assessment of degree of improvement related to the interaction. The program content was validated by 5 academic glaucoma subspecialists. Then, 34 fellowship-trained glaucoma specialists and 21 ophthalmology residents accessed the program. Results were evaluated using paired and nonpaired t tests and analysis of variance. Comparison of pretest and posttest scores of residents and glaucoma specialists on measures of gonioscopy recognition and questions related to ACG management. Residents improved their recognition of gonioscopic findings after viewing the program (P<0.0001), scoring significantly worse than glaucoma specialists before interacting with the program (P<0.0001), but scoring at equivalent levels to specialists after viewing the program (P=0.34). The time necessary to improve knowledge by interacting with the program was significantly related to year of residency training (P<0.0001, analysis of variance). The rate of correct answers to management questions related to ACG increased with increasing years of experience in ophthalmology, validating the education methodology (P<0.0001). A web-based teaching approach for diagnosis and management of ACG evaluated the knowledge of ophthalmologists in a manner consistent with their expected expertize. Statistically significant improvements in validated knowledge of ACG were demonstrated for this educational method.

Evidence for the Role of Proton Shell Closure in Quasifission Reactions from X-Ray Fluorescence of Mass-Identified Fragments

NASA Astrophysics Data System (ADS)

Morjean, M.; Hinde, D. J.; Simenel, C.; Jeung, D. Y.; Airiau, M.; Cook, K. J.; Dasgupta, M.; Drouart, A.; Jacquet, D.; Kalkal, S.; Palshetkar, C. S.; Prasad, E.; Rafferty, D.; Simpson, E. C.; Tassan-Got, L.; Vo-Phuoc, K.; Williams, E.

2017-12-01

The atomic numbers and the masses of fragments formed in quasifission reactions are simultaneously measured at scission in 48Ti + 238U reactions at a laboratory energy of 286 MeV. The atomic numbers are determined from measured characteristic fluorescence x rays, whereas the masses are obtained from the emission angles and times of flight of the two emerging fragments. For the first time, thanks to this full identification of the quasifission fragments on a broad angular range, the important role of the proton shell closure at Z =82 is evidenced by the associated maximum production yield, a maximum predicted by time-dependent Hartree-Fock calculations. This new experimental approach gives now access to precise studies of the time dependence of the N /Z (neutron over proton ratios of the fragments) evolution in quasifission reactions.

Symplectic integration of closed chain rigid body dynamics with internal coordinate equations of motion

NASA Astrophysics Data System (ADS)

Mazur, Alexey K.

1999-07-01

Internal coordinate molecular dynamics (ICMD) is a recent efficient method for modeling polymer molecules which treats them as chains of rigid bodies rather than ensembles of point particles as in Cartesian MD. Unfortunately, it is readily applicable only to linear or tree topologies without closed flexible loops. Important examples violating this condition are sugar rings of nucleic acids, proline residues in proteins, and also disulfide bridges. This paper presents the first complete numerical solution of the chain closure problem within the context of ICMD. The method combines natural implicit fixation of bond lengths and bond angles by the choice of internal coordinates with explicit constraints similar to Cartesian dynamics used to maintain the chain closure. It is affordable for large molecules and makes possible 3-5 times faster dynamics simulations of molecular systems with flexible rings, including important biological objects like nucleic acids and disulfide-bonded proteins.

Modeling the interaction between plant canopies and the planetary boundary layer using a new 1D multi-layer soil- vegetation-atmosphere transfer (SVAT) scheme combined with a non-local turbulence closure model

NASA Astrophysics Data System (ADS)

Yetzer, Kenneth H.

A new one-dimensional (1D) soil-vegetation-atmospheric transport (SVAT) scheme is coupled to a nonlocal turbulence closure model in order to simulate the interactions between a forested canopy and the planetary boundary layer. The SVAT consists of mechanistic models for both physiological (photosynthesis, stomatal conductance and soil/root and bole respiration) and micrometeorological (radiative transfer and surface energy exchanges) processes. The turbulence closure model is a first-order, nonlocal turbulence closure called transilient turbulence theory (Stull, 1993; Inclan et al., 1995) which includes the effects of form drag, wake turbulence, and interference to vertical mixing by the plant elements. The submodel that accounts for radiative transfer inside the forest has been taken from Norman (1979) and Baldocchi (1989). It includes the effect of varying mean leaf inclination angle with height and it also accounts for leaf clumping The photosynthesis submodel is taken from Nikolov and others (1995). It accounts for both differences between shaded and sunlit leaves and the variation of photosynthetic capacity with height. The model was tested with data obtained from a deciduous forest in Pennsylvania. The results show reasonable agreement with the observations. They also demonstrate the model's ability to simulate phenomena that is characteristic of tall canopies like forests, including counter gradient-fluxes and local wind speed maxima in the trunk space.

A randomised crossover study comparing bimatoprost and latanoprost in subjects with primary angle closure glaucoma.

PubMed

How, A C S; Kumar, R S; Chen, Y-M; Su, D H; Gao, H; Oen, F T; Ho, C-L; Seah, S K; Aung, T

2009-06-01

To compare the intraocular pressure (IOP) lowering efficacy and side effects of latanoprost 0.005% and bimatoprost 0.03% in subjects with chronic primary angle closure glaucoma (PACG). This was an observer-masked randomised crossover study of 60 PACG subjects who received either latanoprost or bimatoprost for 6 weeks, after which they were crossed over to the other medication for another 6 weeks. The IOP-reducing effect of the medications was assessed by the reduction in IOP after 6 weeks of treatment compared with baseline. Fifty-four subjects (80 eyes) completed the study. Latanoprost reduced IOP (mean (SD)) by 8.4 (3.8) mm Hg and bimatoprost by 8.9 (3.9) mm Hg from a baseline of 25.2 (3.6) mm Hg and 25.2 (3.6) mm Hg respectively (p = 0.23). Adverse events were mild in both groups; however there were twice as many reports of an adverse event in the bimatoprost group (81%) compared with the latanoprost group (40%, p<0.01). Ocular irritation was the most frequently reported adverse event in both groups; 22 subjects (37.9%) treated with bimatoprost experienced ocular hyperaemia as compared with 13 subjects (22.4%) treated with latanoprost (p = 0.11). Bimatoprost once daily was similarly effective in reducing IOP compared with latanoprost once daily in subjects with chronic PACG. Both drugs were well tolerated with mild ocular adverse events.

Ultrasound biomicroscopic analysis of iris cysts.

PubMed

Pedro-Aguilar, L; Fuentes-Cataño, C; Pedroza-Seres, M

2016-02-01

To describe the ultrasound biomicroscopic (UBM) features and complications associated with iris cysts. A retrospective case series. Thirteen patients with iris cysts were identified in a 10 year period study at a ophthalmologic reference Center in Mexico City. The variables included demographic data, ocular and medical history, clinical course, and complications. All patients were examined by UBM, and type, number, location, and acoustic characteristics of cysts were evaluated. Descriptive statistics were performed. Thirteen patients were included (8 men and 5 women). The mean age was 44.5 ± 15.5 years (range 6-70 years). The origin most prevalent was neuroepithelial (92.3%), and 7.7% had stromal cysts. Regarding to location 76.9% were found in the periphery, and 69.2% between meridians II and VI. All cysts showed a moderate to high reflectivity in the wall. Complications were present in 38.5% of cases (15.4% partial angle closure, 15.4% secondary angle closure glaucoma and 7.7% dyscoria). Most cysts are derived from iris pigmented epithelium, with a benign course and a minor rate of complications. The UBM is an indispensable tool that allows us to plan more specific and conservative treatments, with less damage to ocular structures and, therefore, better visual prognosis. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Imaging the asymmetric dust shell around CI Cam with long baseline optical interferometry

NASA Astrophysics Data System (ADS)

Thureau, N. D.; Monnier, J. D.; Traub, W. A.; Millan-Gabet, R.; Pedretti, E.; Berger, J.-P.; Garcia, M. R.; Schloerb, F. P.; Tannirkulam, A.-K.

2009-09-01

We present the first high angular resolution observation of the B[e] star/X-ray transient object CI Cam, performed with the two-telescope Infrared Optical Telescope Array (IOTA), its upgraded three-telescope version (IOTA3T) and the Palomar Testbed Interferometer (PTI). Visibilities and closure phases were obtained using the IONIC-3 integrated optics beam combiner. CI Cam was observed in the near-infrared H and K spectral bands, wavelengths well suited to measure the size and study the geometry of the hot dust surrounding CI Cam. The analysis of the visibility data over an 8yr period from soon after the 1998 outburst to 2006 shows that the dust visibility has not changed over the years. The visibility data show that CI Cam is elongated which confirms the disc-shape of the circumstellar environment and totally rules out the hypothesis of a spherical dust shell. Closure phase measurements show direct evidence of asymmetries in the circumstellar environment of CI Cam and we conclude that the dust surrounding CI Cam lies in an inhomogeneous disc seen at an angle. The near-infrared dust emission appears as an elliptical skewed Gaussian ring with a major axis a = 7.58 +/- 0.24mas, an axis ratio r = 0.39 +/- 0.03 and a position angle θ = 35° +/- 2°.

Corneal indentation in the early management of acute angle closure.

PubMed

Masselos, Katherine; Bank, Allan; Francis, Ian C; Stapleton, Fiona

2009-01-01

To describe in detail corneal indentation (CI) in the management of a series of patients treated for acute angle closure (AAC). Retrospective, consecutive, noncomparative case series. Seven consecutive patients (8 eyes) referred to the authors with the diagnosis of AAC. Patients presented to the Prince of Wales Hospital, Randwick, or to the private practices of the authors. Seven patients (8 eyes) underwent CI as part of their early management for AAC. Reduction in intraocular pressure (IOP), symptoms of AAC and pain relief. Of the 7 patients, complete data were available for 6. The IOP was significantly reduced (P<0.05) and 3 of 4 patients with severe acute pain reported early resolution of pain after CI. The average reduction in IOP was 20.9 mmHg (range +1 to -45). All patients subsequently underwent definitive management with laser peripheral iridotomies or lensectomy using phacoemulsification. Three patients treated acutely with CI without any medical agents had a mean IOP reduction of 21 mmHg (range, 20-23) after indentation. Corneal indentation is a rapid, portable, and effective method of reducing elevated IOP in the setting of AAC. It can be performed with instrumentation that is readily at hand and allows for rapid pain relief. This reduction in IOP improves corneal clarity and permits further definitive management of the patient with AAC. The authors have no proprietary or commercial interest in any materials discussed in this article.

Agreement between gonioscopy and ultrasound biomicroscopy in detecting iridotrabecular apposition.

PubMed

Barkana, Yaniv; Dorairaj, Syril K; Gerber, Yariv; Liebmann, Jeffrey M; Ritch, Robert

2007-10-01

To assess the agreement between findings obtained at dark-room gonioscopy and ultrasound biomicroscopy (UBM) in the diagnosis of iridotrabecular apposition in light and dark conditions. We enrolled patients with appositional angle closure at dark-room gonioscopy performed using a 1-mm slitlamp beam that did not cross the pupil. Ultrasound biomicroscopic images were acquired in normal room light and subsequently with all room lights off. Images were evaluated for the presence or absence of iris-cornea contact. The angle opening distance at 500 microm was calculated. Iridotrabecular apposition in at least 1 angle quadrant was demonstrated in all 18 eyes at dark-room gonioscopy, 17 eyes (94%) at dark-room UBM, and only 10 eyes (56%) at UBM in room light. Of 18 superior angles that were appositionally closed at dark-room gonioscopy, apposition was demonstrated on UBM images in 16 (89%) in a dark room but only 6 (33%) in room light. Angle opening distance was less during dark-room gonioscopy in all but the nasal quadrant. We found high agreement between gonioscopy and UBM when both are performed in a completely dark room. Our findings support the recommendation that, in routine clinical practice, gonioscopy be performed in a dark room to avoid misdiagnosis of treatable iridotrabecular apposition.

Geometrically Thick Obscuration by Radiation-driven Outflow from Magnetized Tori of Active Galactic Nuclei

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Chi-Ho; Krolik, Julian H.

2017-07-01

Near-Eddington radiation from active galactic nuclei (AGNs) has significant dynamical influence on the surrounding dusty gas, plausibly furnishing AGNs with geometrically thick obscuration. We investigate this paradigm with radiative magnetohydrodynamics simulations. The simulations solve the magnetohydrodynamics equations simultaneously with the infrared (IR) and ultraviolet (UV) radiative transfer (RT) equations; no approximate closure is used for RT. We find that our torus, when given a suitable sub-Keplerian angular momentum profile, spontaneously evolves toward a state in which its opening angle, density distribution, and flow pattern change only slowly. This “steady” state lasts for as long as there is gas resupply towardmore » the inner edge. The torus is best described as a midplane inflow and a high-latitude outflow. The outflow is launched from the torus inner edge by UV radiation and expands in solid angle as it ascends; IR radiation continues to drive the wide-angle outflow outside the central hole. The dusty outflow obscures the central source in soft X-rays, the IR, and the UV over three-quarters of solid angle, and each decade in column density covers roughly equal solid angle around the central source; these obscuration properties are similar to what observations imply.« less

PLATEAU IRIS – DIAGNOSIS AND TREATMENT

PubMed Central

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

Objectives: The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Systematic review methodology: Relevant publications on plateau iris that were published until 2014. Conclusions: Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty PMID:27373109

PLATEAU IRIS SYNDROME--CASE SERIES.

PubMed

Feraru, Crenguta Ioana; Pantalon, Anca Delia; Chiselita, Dorin; Branisteanu, Daniel

2015-01-01

Plateau iris is characterized by closing the anterior chamber angle due to a large ciliary body or due to its anterior insertion that alters the position of iris periphery in respect to the trabecular meshwork. There are two aspects that need to be differentiated: plateau iris configuration and plateau iris syndrome. The first describes a situation when the iris root is flat and the anterior chamber is not shallow, the latter refers to a post laser iridotomy condition in which a patent iridotomy has removed the relative pupillary block, but goniscopically confirmed angle closure recurs without central shallowing of the anterior chamber. Isolated plateau iris syndrome is rare compared to plateau iris configuration. We hereby present two case reports of plateau iris syndrome in young patients who came to an ophthalmologic consult by chance.

The effect of internal fixation lamp on anterior chamber angle width measured by anterior segment optical coherence tomography.

PubMed

Nakamine, Sakari; Sakai, Hiroshi; Arakaki, Yoshikuni; Yonahara, Michiko; Kaiya, Tadayoshi

2018-01-01

To study the effect of the internal fixation lamp on anterior chamber width measured by anterior segment optical coherence tomography. In a prospective cross sectional observational study, consecutive 22 right eyes of 22 patients (4 men and 18 women) with suspected primary angle closure underwent swept source domain anterior segment optical coherence tomography (AS-OCT), (CASIA SS-1000, Tomey, Nagoya, Japan). Anterior chamber parameters of angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA) at 500 or 750 µm from scleral spur and pupil diameter were measured by AS-OCT in a three-dimensional mode in 4 quadrants (superior, inferior, temporal and nasal) in dark room setting both with and without internal fixation lamp. Anterior segment parameters of AOD 500 in superior, inferior and temporal quadrants, AOD 750 at superior and nasal, TIA 500 at superior, and inferior and TIA 750 at superior and nasal, and ARA 500 or 750 at superior and inferior with internal fixation lamp were greater and the pupil diameter was significantly (all P < 0.05, paired t test) smaller than when measured without fixation lamp. Internal fixation lamp of the anterior segment OCT makes the pupil constrict and angle wider. When using AS-OCT with usual setting with internal fixation lamp on with eyes in which the anterior chamber angle is narrow but open, it is recommended that the internal fixation lamp be turned off to ensure a clear indication as to whether the angle is open or closed in the dark.

Anterior Chamber Angle Measurements Using Schwalbe's Line with High Resolution Fourier-Domain Optical Coherence Tomography

PubMed Central

Qin, Bing; Francis, Brian A.; Li, Yan; Tang, Maolong; Zhang, Xinbo; Jiang, Chunhui; Cleary, Catherine; Huang, David

2012-01-01

Purpose To use Fourier-domain optical coherence tomography (OCT) to measure the angle opening distance at Schwalbe's line (AOD-SL) and determine its value in anterior chamber angle assessment. Methods Horizontal scans of the nasal and temporal anterior chamber angles in glaucoma subjects were performed by 830 nm wavelength Fourier-domain OCT. Images were graded by two ophthalmologists who assessed the visibility of Schwalbe’s line (SL), anterior limbus (AL), scleral spur (SS), and angle recess (AR). AOD-SL was measured with computer calipers. SL was manually identified by the termination of the corneal endothelium. Gonioscopy was used to classify anterior chamber angles according to a modified Shaffer system. Spearman's rho analysis was performed to assess correlation between AOD-SL and modified Shaffer grade. A cut-off value of AOD-SL for diagnosing occludable angles (modified Shaffer grade ≤1) was determined by receiver operating characteristic (ROC) analyses. Results Thirty-five glaucoma subjects (65 eyes) were enrolled. SL, AL, AR, and SS were visible by OCT in 97.7%, 99.2%, 87.3%, and 80.8% of eyes, respectively. Nasal and temporal AOD-SLs were 322.6 ± 200.2 µm and 341.4 ± 197.4 µm, respectively. Correlation coefficients between AOD-SL and modified Shaffer grade were 0.80 (nasal) and 0.81 (temporal). The diagnostic cut-off value of AOD-SL for occludable angles was 290 µm. The areas under the ROC curve, sensitivity, specificity values were 0.90, 0.80, 0.87 (nasal) and 0.90, 0.85, 0.77 (temporal). Conclusions The measurement of AOD-SL by Fourier-domain OCT is highly correlated with gonioscopy and may be a useful noncontact method of assessing angle closure risk. PMID:22827999

Relationship between iris surface features and angle width in Asian eyes.

PubMed

Sidhartha, Elizabeth; Nongpiur, Monisha Esther; Cheung, Carol Y; He, Mingguang; Wong, Tien Yin; Aung, Tin; Cheng, Ching-Yu

2014-10-23

To examine the associations between iris surface features with anterior chamber angle width in Asian eyes. In this prospective cross-sectional study, we recruited 600 subjects from a large population-based study, the Singapore Epidemiology of Eye Diseases (SEED) study. We obtained standardized digital slit-lamp iris photographs and graded the iris crypts (by number and size), furrows (by number and circumferential extent), and color (higher grade denoting darker iris). Vertical and horizontal cross-sections of anterior chamber were imaged using anterior segment optical coherence tomography. Angle opening distance (AOD), angle recess area (ARA), and trabecular-iris space area (TISA) were measured using customized software. Associations of the angle width with the iris surface features in the subject's right eyes were assessed using linear regression analysis. A total of 464 eyes of the 464 subjects (mean age: 57.5 ± 8.6 years) had complete and gradable data for crypts and color, and 423 eyes had gradable data for furrows. After adjustment for age, sex, ethnicity, pupil size, and corneal arcus, higher crypt grade was independently associated with wider AOD750 (β [change in angle width per grade higher] = 0.018, P = 0.023), ARA750 (β = 0.022, P = 0.049), and TISA750 (β = 0.011, P = 0.019), and darker iris was associated narrower ARA750 (β = -0.025, P = 0.044) and TISA750 (β = -0.013, P = 0.011). Iris surface features, assessed and measured from slit-lamp photographs, correlated well with anterior chamber angle width; irises with more crypts and lighter color were associated with wider angle. These findings may provide another imaging modality to assess angle closure risk based on iris surface features. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

A compressible Navier-Stokes solver with two-equation and Reynolds stress turbulence closure models

NASA Technical Reports Server (NTRS)

Morrison, Joseph H.

1992-01-01

This report outlines the development of a general purpose aerodynamic solver for compressible turbulent flows. Turbulent closure is achieved using either two equation or Reynolds stress transportation equations. The applicable equation set consists of Favre-averaged conservation equations for the mass, momentum and total energy, and transport equations for the turbulent stresses and turbulent dissipation rate. In order to develop a scheme with good shock capturing capabilities, good accuracy and general geometric capabilities, a multi-block cell centered finite volume approach is used. Viscous fluxes are discretized using a finite volume representation of a central difference operator and the source terms are treated as an integral over the control volume. The methodology is validated by testing the algorithm on both two and three dimensional flows. Both the two equation and Reynolds stress models are used on a two dimensional 10 degree compression ramp at Mach 3, and the two equation model is used on the three dimensional flow over a cone at angle of attack at Mach 3.5. With the development of this algorithm, it is now possible to compute complex, compressible high speed flow fields using both two equation and Reynolds stress turbulent closure models, with the capability of eventually evaluating their predictive performance.

Evaluation of the anterior chamber angle in glaucoma: a report by the american academy of ophthalmology.

PubMed

Smith, Scott D; Singh, Kuldev; Lin, Shan C; Chen, Philip P; Chen, Teresa C; Francis, Brian A; Jampel, Henry D

2013-10-01

To assess the published literature pertaining to the association between anterior segment imaging and gonioscopy and to determine whether such imaging aids in the diagnosis of primary angle closure (PAC). Literature searches of the PubMed and Cochrane Library databases were last conducted on July 6, 2011. The searches yielded 371 unique citations. Members of the Ophthalmic Technology Assessment Committee Glaucoma Panel reviewed the titles and abstracts of these articles and selected 134 of possible clinical significance for further review. The panel reviewed the full text of these articles and identified 79 studies meeting the inclusion criteria, for which the panel methodologist assigned a level of evidence based on a standardized grading scheme adopted by the American Academy of Ophthalmology. Three, 70, and 6 studies were rated as providing level I, II, and III evidence, respectively. Quantitative and qualitative parameters defined from ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (OCT), Scheimpflug photography, and the scanning peripheral anterior chamber depth analyzer (SPAC) demonstrate a strong association with the results of gonioscopy. There is substantial variability in the type of information obtained from each imaging method. Imaging of structures posterior to the iris is possible only with UBM. Direct imaging of the anterior chamber angle (ACA) is possible using UBM and OCT. The ability to acquire OCT images in a completely dark environment allows greater sensitivity in detecting eyes with appositional angle closure. Noncontact imaging using OCT, Scheimpflug photography, or SPAC makes these methods more attractive for large-scale PAC screening than contact imaging using UBM. Although there is evidence suggesting that anterior segment imaging provides useful information in the evaluation of PAC, none of these imaging methods provides sufficient information about the ACA anatomy to be considered a substitute for gonioscopy. Longitudinal studies are needed to validate the diagnostic significance of the parameters measured by these instruments for prospectively identifying individuals at risk for PAC. Proprietary or commercial disclosure may be found after the references. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Glaucoma anterior chamber morphometry based on optical Scheimpflug images.

PubMed

Alonso, Ruiz Simonato; Ambrósio Junior, Renato; Paranhos Junior, Augusto; Sakata, Lisandro Massanori; Ventura, Marcelo Palis

2010-01-01

To compare the performance of gonioscopy and noncontact morphometry with anterior chamber tomography (High Resolution Pentacam - HR) using optical Scheimpflug images in the evaluation of the anterior chamber angle (ACA). Transversal study. 112 eyes from 74 subjects evaluated at the Glaucoma Department, Fluminense Federal University, underwent gonioscopy and Pentacam HR. Using gonioscopy, the ACA was graded using the Shaffer Classification (SC) by a single experienced examiner masked to the Pentacam HR findings. Narrow angle was determined in eyes in which the posterior trabecular meshwork could not be seen in two or more quadrants on non-indentation gonioscopy (SC Grade 2 or less). Pentacam HR images of the nasal and temporal quadrants were evaluated by custom software to automatically obtain anterior chamber measurements, such as: anterior chamber angle (ACA), anterior chamber volume (ACV) and anterior chamber depth (ACD). Based on gonioscopy results, 74 (60.07%) eyes of patients classified as open-angle (SC 3 and 4) and 38 (33.93%) eyes of patients classified as narrow-angle (SC 1 and 2). Noncontact morphometry with Scheimpflug images revealed a mean ACA of 39.20 ± 5.31 degrees for open-angle and 21.18 ± 7.98 degrees for narrow-angle. The open-angle group showed significant greater ACV and ACD values when compared to narrow-angle group (ACV of 193 ± 36 mm³ vs. 90 ± 25 mm³, respectively, p<0.001; and ACD of 3,09 ± 0,42 mm vs. 1,55 ± 0,64 mm, respectively, p<0.0001.). In screening eyes with open-angle and narrow-angle with the Pentacam ACA of 20º (SC Grade 2) using the ROC curves, the analysis showed 52.6% of sensitivity and 100% of specificity. The Pentacam showed ability in detecting eyes at risk for angle closure analyzing ACV and ACD.

Comparison of anchorage reinforcement with temporary anchorage devices or a Herbst appliance during lingual orthodontic protraction of mandibular molars without maxillary counterbalance extraction.

PubMed

Metzner, Rebecca; Schwestka-Polly, Rainer; Helms, Hans-Joachim; Wiechmann, Dirk

2015-06-20

Orthodontic protraction of mandibular molars without maxillary counterbalance extraction in cases of aplasia or extraction requires stable anchorage. Reinforcement may be achieved by using either temporary anchorage devices (TAD) or a fixed, functional appliance. The objective was to compare the clinical effectiveness of both methods by testing the null-hypothesis of no significant difference in velocity of space closure (in mm/month) between them. In addition, we set out to describe the quality of posterior space management and treatment-related factors, such as loss of anchorage (assessed in terms of proportions of gap closure by posterior protraction or anterior retraction), frequencies of incomplete space closure, and potential improvement in the sagittal canine relationship. Twenty-seven subjects (15 male/12 female) with a total of 36 sites treated with a lingual multi-bracket appliance were available for retrospective evaluation of the effects of anchorage reinforcement achieved with either a Herbst appliance (n(subjects) = 15; 7 both-sided/8 single-sided Herbst appliances; n(sites) = 22) or TADs (n(subjects )= 12; 2 both-sided; 10 single-sided; n(sites) = 14). Descriptive analysis was based on measurements using intra-oral photographs which were individually scaled to corresponding plaster casts and taken on insertion of anchorage mechanics (T1), following removal of anchorage mechanics (T2), and at the end of multi-bracket treatment (T3). The null-hypothesis was rejected: The rate of mean molar protraction was significantly faster in the Herbst-reinforced group (0.51 mm/month) than in the TAD group (0.35). While complete space closure by sheer protraction of posterior teeth was achieved in all Herbst-treated cases, space closure in the TAD group was achieved in 76.9% of subjects by sheer protraction of molars, and it was incomplete in 50% of cases (mean gap residues: 1 mm). Whilst there was a deterioration in the canine relationship towards Angle-Class II malocclusion in 57.14% of space closure sites in TAD-treated subjects (indicating a loss of anchorage), an improvement in canine occlusion was observed in 90.9% of Herbst-treated cases. Subjects requiring rapid space closure by molar protraction in combination with a correction of distal occlusion may benefit from using Herbst appliances for anterior segment anchorage reinforcement rather than TAD anchorage.

Comparing Laser Peripheral Iridotomy to Cataract Extraction in Narrow Angle Eyes Using Anterior Segment Optical Coherence Tomography

PubMed Central

Melese, Ephrem; Peterson, Jeffrey R.; Feldman, Robert M.; Baker, Laura A.; Bell, Nicholas P.; Chuang, Alice Z.

2016-01-01

Purpose To evaluate the changes in anterior chamber angle (ACA) parameters in primary angle closure (PAC) spectrum eyes before and after cataract extraction (CE) and compare to the changes after laser peripheral iridotomy (LPI) using anterior segment optical coherence tomography (ASOCT). Methods Twenty-eight PAC spectrum eyes of 18 participants who underwent CE and 34 PAC spectrum eyes of 21 participants who underwent LPI were included. ASOCT images with 3-dimensional mode angle analysis scans were taken with the CASIA SS-1000 (Tomey Corp., Nagoya, Japan) before and after CE or LPI. Mixed-effect model analysis was used to 1) compare best-corrected visual acuity, intraocular pressure, and ACA parameters before and after CE; 2) identify and estimate the effects of potential contributing factors affecting changes in ACA parameters; and 3) compare CE and LPI treatment groups. Results The increase in average angle parameters (TISA750 and TICV750) was significantly greater after CE than LPI. TICV750 increased by 102% (2.114 [±1.203] μL) after LPI and by 174% (4.546 [± 1.582] μL) after CE (P < 0.001). Change of TICV750 in the CE group was significantly affected by age (P = 0.002), race (P = 0.006), and intraocular lens power (P = 0.037). Conclusions CE results in greater anatomic changes in the ACA than LPI in PAC spectrum eyes. ASOCT may be used to follow anatomic changes in the angle after intervention. PMID:27606482

The carina angle-new geometrical parameter associated with periprocedural side branch compromise and the long-term results in coronary bifurcation lesions with main vessel stenting only.

PubMed

Gil, Robert J; Vassilev, Dobrin; Formuszewicz, Radoslaw; Rusicka-Piekarz, Teresa; Doganov, Alexander

2009-12-01

The two main problems unresolved in coronary bifurcation stenting are periprocedural side branch compromise and higher restenosis at long term. The purpose of this study is to reveal the link between periprocedural side branch compromise and long-term results after main vessel stenting only in coronary bifurcations. Eighty-four patients formed the study population. The inclusion criteria were good-quality angiograms, with maximal between-branch angle opening, no overlap, permitting accurate angiographic analysis. Carina angle (alpha)-the distal angle between main vessel (MV) before bifurcation and side branch (SB)-was measured pre- and poststenting. Clinical follow-up 9-12 months was obtained with coronary angiography if needed. The patient population was high-risk with 33% diabetics and 84% two- and three-vessel disease. Ninety-five stents were implanted in 92 lesions, with three T-stenting cases. Drug-eluting stents were implanted in 54%. Kissing-balloon (KBI) or sequential inflation was performed in 35%. SB functional closure occurred in 17.4%, with independent predictors alpha < 40 degrees and diameter ratio MB/SB >1.22. After 12+/-4 months there were five myocardial infarctions (6%) and 13 (15%) target lesion revascularization procedures. Independent predictors of major cardiovascular events were carina angle <40 degrees , MB lesion length >8 mm, negative change of between-branch angle, DES usage, and KBI. Smaller carina angle with straightening of MV-main branch from stent implantation in coronary bifurcations predicted higher SB compromise, restenosis, and MACE rates during follow-up of 1 year.

Self-Assembly of Flux-Closure Polygons from Magnetite Nanocubes.

PubMed

Szyndler, Megan W; Corn, Robert M

2012-09-06

Well-defined nanoscale flux-closure polygons (nanogons) have been fabricated on hydrophilic surfaces from the face-to-face self-assembly of magnetite nanocubes. Uniform ferrimagnetic magnetite nanocubes (∼86 nm) were synthesized and characterized with a combination of electron microscopy, diffraction, and magnetization measurements. The nanocubes were subsequently cast onto hydrophilic substrates, wherein the cubes lined up face-to-face and formed a variety of polygons due to magnetostatic and hydrophobic interactions. The generated surfaces consist primarily of three- and four-sided nanogons; polygons ranging from two to six sides were also observed. Further examination of the nanogons showed that the constraints of the face-to-face assembly of nanocubes often led to bowed sides, strained cube geometries, and mismatches at the acute angle vertices. Additionally, extra nanocubes were often present at the vertices, suggesting the presence of external magnetostatic fields at the polygon corners. These nanogons are inimitable nanoscale magnetic structures with potential applications in the areas of magnetic memory storage and high-frequency magnetics.

Few Skewed Results from IOTA Interferometer YSO Disk Survey

NASA Astrophysics Data System (ADS)

Monnier, J. D.; Millan-Gabet, R.; Berger, J.-P.; Pedretti, E.; Traub, W.; Schloerb, F. P.

2005-12-01

The 3-telescope IOTA interferometer is capable of measuring closure phases for dozens of Herbig Ae/Be stars in the near-infrared. The closure phase unambiguously identifies deviations from centro-symmetry (i.e., skew) in the brightness distribution, at the scale of 4 milliarcseconds (sub-AU physical scales) for our work. Indeed, hot dust emission from the inner circumstellar accretion disk is expected to be skewed for (generic) flared disks viewed at intermediate inclination angles, as has been observed for LkHa 101. Surprisingly, we find very little evidence for skewed disk emission in our IOTA3 sample, setting strong constraints on the geometry of the inner disk. In particular, we rule out the currently-popular model of a VERTICAL hot inner wall of dust at the sublimation radius. Instead, our data is more consistent with a curved inner wall that bends away from the midplane as might be expected from the pressure-dependence of dust sublimation or limited absorption of stellar luminosity in the disk midplane by gas.

Modelling the detachment dependence on strike point location in the small angle slot divertor (SAS) with SOLPS

NASA Astrophysics Data System (ADS)

Casali, Livia; Covele, Brent; Guo, Houyang

2017-10-01

The new Small Angle Slot (SAS) divertor in DIII-D is characterized by a shallow-angle target enclosed by a slot structure about the strike point (SP). SOLPS modelling results of SAS have demonstrated divertor closure's utility in widening the range of acceptable densities for adequate heat handling. An extensive database of runs has been built to study the detachment dependence on SP location in SAS. Density scans show that lower Te at lower upstream density occur when the SP is at the critical location in the slot. The cooling front spreads across the entire target at higher densities, in agreement with experimental Langmuir probe measurements. A localized increase of the atomic and molecular density takes place near the SP, which reduces the target incident power density and facilitates detachment at lower upstream density. Systematic scans of variables such as power, transport, and viscosity have been carried out to assess the detachment sensitivity. Therein, a positive role of the viscosity is found. This work supported by DOE Contract Number DE-FC02-04ER54698.

Physical analysis and second-order modelling of an unsteady turbulent flow - The oscillating boundary layer on a flat plate

NASA Technical Reports Server (NTRS)

Ha Minh, H.; Viegas, J. R.; Rubesin, M. W.; Spalart, P.; Vandromme, D. D.

1989-01-01

The turbulent boundary layer under a freestream whose velocity varies sinusoidally in time around a zero mean is computed using two second order turbulence closure models. The time or phase dependent behavior of the Reynolds stresses are analyzed and results are compared to those of a previous SPALART-BALDWIN direct simulation. Comparisons show that the second order modeling is quite satisfactory for almost all phase angles, except in the relaminarization period where the computations lead to a relatively high wall shear stress.

The evaluation of eye pain with a normal ocular exam.

PubMed

Lee, Andrew G; Brazis, Paul W

2003-12-01

Eye pain with or without associated head or face pain is a common complaint to the ophthalmologist. The ocular exam may reveal the etiology (e.g., corneal disease, angle closure glaucoma) but typically the exam is normal. This paper reviews the evaluation and management of eye pain with a "normal" ocular exam, including: 1) subtle findings on ocular exam; 2) transient findings on exam, and 3) no abnormal ocular findings. Ophthalmologists should be aware of the various etiologies for eye pain and the specific and distinctive features that make the diagnosis.

[21st century management of glaucoma].

PubMed

Tsukahara, Shigeo

2003-12-01

According to a recent epidemiological study done in Japan, 2 or 3 million Japanese people are thought to be suffering from glaucoma, and 70-80% of them have not been examined or diagnosed by ophthalmologists. Therefore, the problem is how to find these untreated and undiagnosed people. At present, treatment of glaucoma continues to be directed at lowering intraocular pressure to prevent progression of glaucomatous optic neuropathy. However, theoretically, there are three stages in the prevention of progression of glaucoma. In the first stage, diagnosis of glaucoma can be done by genetic examination, before occurrence of glaucoma. The MYOCILIN/trabecular meshwork-inducible glucocorticoid response gene and the optineurin gene were identified as the genes that cause open angle glaucoma. Although some Japanese patients have sequence changes in the myocilin gene, there are no apparent specific mutations in Japanese glaucoma patients, in the MYOCILIN/TIGR and optineurin genes. Secondary glaucoma such as steroid glaucoma, induced by allergic diseases, and neovascular glaucoma, induced by retinal circulatory insufficiency, are preventable by improving the causal diseases, diabetes and hypertension. The education of doctors and laymen is important to reduce the occurrence of diabetes, and hypertension to prevent diabetic retinopathy, and retinal vessel occlusion. The second stage in preventing progression of glaucoma is to find the disease as early as possible. In Japan, a physical examination system is in place for everybody over 40 years old, in companies and local districts. Therefore, ocular examination, specially non-mydriatic fundus photographs should be taken in these examinations, and the film should be evaluated by an ophthalmologist, to search for retinal and optic disc abnormalities. Primary open angle glaucoma can be detected through this system in early stages. In primary angle closure glaucoma, instruments for estimating anterior chamber rapidly and accurately are necessary for the diagnosis. There is a special machine which can be handled easily, safely, and economically for detecting angle closure glaucoma, has been developed by Yamanashi University. This machine might help to reduce the number of angle closure glaucoma patients in the world. In the near future, a glaucoma network system should be put in place all over Japan. This organization consists of central headquarter and local central office. Most hospitals and private offices will belong to a local central office, and several glaucoma specialists will work in central and local offices. All glaucoma patients will be registered in local glaucoma office. The information on glaucoma patients will be communicated in the system the through light fiber cables or a satellite system. The patients can ask about their own disease through this glaucoma center system. In the third stage of glaucoma prevention, progression of glaucomatous optic neuropathy is retarded by conventional IOP lowering treatment or neuroprotective drugs. This stage compromises rehabilitation of visual function, implant of artificial visual systems, and regeneration of retinal ganglion cells(RGC). The disturbances of axonal flow in guinea pig optic nerve fibers was demonstrated electromicroscopically by quick-freeze, deep-etching method and, the decrease in numbers of motor proteins like "Kinesin" "Dynein" and "MAP-1" was shown in guinea pig eyes with elevated intraocular pressure by immunohistochemistry. Retinal glanglion cells have been isolated and new findings have been reported using this RGC culture system. Therefore, new neuroprotective drugs will be developed through this culture system.

Lip and Lower Lid Supporting Prosthetic Appliance: A Unique Approach of Treating Unilateral Facial Paralysis

PubMed Central

Pawah, Salil; Sikri, Arpit; Rexwal, Pushpanjali; Aggarwal, Prachi

2017-01-01

Along with function, aesthetics plays an important role in treating partially or completely edentulous patients. Ageing, trauma, tooth loss and neuromuscular disorders have a high impact on tonicity of facial musculature, elasticity of skin as well as function of muscles. Patients affected with Bell’s palsy face functional, aesthetic as well as psychological impairment. Common problems are the partial closure of upper eyelid, sagging of lower eyelid and drooping of angle of mouth leading to facial asymmetry, along with difficulty in eating, drinking and speaking. The key to aesthetic restoration is to support and harmonize the collapsed facial musculature with the help of various prosthodontic treatment approaches. This case report attempts to focus on treating completely edentulous patient affected with Bell’s palsy with special prosthesis supporting angle of mouth and lower eyelid using novel technique. PMID:28658922

A Population-based survey of the prevalence and types of glaucoma in Nigeria: results from the Nigeria National Blindness and Visual Impairment Survey.

PubMed

Kyari, Fatima; Entekume, Gabriel; Rabiu, Mansur; Spry, Paul; Wormald, Richard; Nolan, Winifred; Murthy, Gudlavalleti V S; Gilbert, Clare E

2015-12-12

Glaucoma is the leading cause of irreversible blindness worldwide. There tends to be a lower reporting of glaucoma in Africa compared to other blinding conditions in global burden data. Research findings of glaucoma in Nigeria will significantly increase our understanding of glaucoma in Nigeria, in people of the West African diaspora and similar population groups. We determined the prevalence and types of glaucoma in Nigeria from the Nigeria National Blindness and Visual Impairment cross-sectional Survey of adults aged ≥40 years. Multistage stratified cluster random sampling with probability-proportional-to-size procedures were used to select a nationally representative sample of 15,027 persons aged ≥40 years. Participants had logMAR visual acuity measurement, FDT visual function testing, autorefraction, A-scan biometry and optic disc assessment. Participants with visual acuity of worse than 6/12 or suspicious optic discs had detailed examination including Goldmann applanation tonometry, gonioscopy and fundus photography. Disc images were graded by Moorfields Eye Hospital Reading Centre. Glaucoma was defined using International Society of Geographical and Epidemiological Ophthalmology criteria; and classified into primary open-angle or primary angle-closure or secondary glaucoma. Diagnosis of glaucoma was based on ISGEO classification. The type of glaucoma was determined by gonioscopy. A total of 13,591 participants in 305 clusters were examined (response rate 90.4 %). Optic disc grading was available for 25,289 (93 %) eyes of 13,081 (96 %) participants. There were 682 participants with glaucoma; a prevalence of 5.02 % (95 % CI 4.60-5.47). Among those with definite primary glaucoma that had gonioscopy (n = 243), open-angle glaucoma was more common (86 %) than angle-closure glaucoma (14 %). 8 % of glaucoma was secondary with the commonest causes being couching (38 %), trauma (21 %) and uveitis (19 %). Only 5.6 % (38/682) of participants with glaucoma knew they had the condition. One in every 5 persons with glaucoma (136;20 %) was blind i.e., visual acuity worse than 3/60. Nigeria has a high prevalence of glaucoma which is largely open-angle glaucoma. A high proportion of those affected are blind. Secondary glaucoma was mostly as a consequence of procedures for cataract. Public health control strategies and high quality glaucoma care service will be required to reduce morbidity and blindness from glaucoma.

A proposal for the molecular basis of μ and δ opiate receptor differentiation based on modeling of two types of cyclic enkephalins and a narcotic alkaloid

NASA Astrophysics Data System (ADS)

Michel, André; Villeneuve, Gérald; DiMaio, John

1991-12-01

The molecular basis underlying the divergent receptor selectivity of two cyclic opioid peptides Tyr-c[ N δ- d-Orn2-Gly-Phe-Leu-] (c-ORN) and [ d-Pen2, l-Cys5]-enkephalinamide (c-PEN) was investigated using a molecular modeling approach. Ring closure and conformational searching procedures were used to determine low-energy cyclic backbone conformers. Following reinsertion of amino acid side chains, the narcotic alkaloid 7α-[(1R)-1-methyl-1-hydroxy-3-phenylpropyl]-6,14-endoethenotetrahydro oripavine (PEO) was used as a flexible template for bimolecular superpositions with each of the determined peptide ring conformers using the coplanarity and cocentricity of the phenolic rings as the minimum constraint. A vector space of PEO, accounting for all possible orientations for the C21-aromatic ring of PEO served as a geometrical locus for the aromatic ring of the Phe4 residue in the opioid peptides. Although a vast number of polypeptide conformations satisfied the criteria of the opiate pharmacophore, they could be grouped into three classes differing in magnitude and sign of the torsional angle values of the tyrosyl side chain. Only class III conformers for both c-ORN and c-PEN, having tyramine dihedral angles χ1 =-150° ± 30° and χ2=-155° ± 20°, had significant structural and conformational properties that were mutually compatible while respecting the PEO vector space. Comparison of these properties in the context of the divergent receptor selectivity of the studied opioid peptides suggests that the increased distortion of the peptide backbone in the closure region of c-PEN together with the pendant β,β-dimethyl group, combine to generate a steric volume which is absent in c-ORN and that may be incompatible with a restrictive topography of the μ receptor. The nature and stereo-chemistry of substituents adjacent to the closure region of the peptides could also modulate receptor selection by interacting with a charged (δ) or neutral (μ) subsite.

Qualitative Assessment of Ultrasound Biomicroscopic Images Using Standard Photographs: The Liwan Eye Study

PubMed Central

Jiang, Yuzhen; Huang, Wenyong; Huang, Qunxiao; Zhang, Jian; Foster, Paul J.

2010-01-01

Objective. To classify anatomic features related to anterior chamber angles by a qualitative assessment system based on ultrasound biomicroscopy (UBM) images. Methods. Cases of primary angle-closure suspect (PACS), defined by pigmented trabecular meshwork that is not visible in two or more quadrants on static gonioscopy (cases) and systematically selected subjects (1 of every 10) who did not meet this criterion (controls) were enrolled during a population-based survey in Guangzhou, China. All subjects underwent UBM examination. A set of standard UBM images was used to qualitatively classify anatomic features related to the angle configuration, including iris thickness, iris convexity, iris angulation, ciliary body size, and ciliary process position. All analysis was conducted on right eye images. Results. Based on the qualitative grades, the difference in overall iris thickness between gonioscopically narrow eyes (n = 117) and control eyes (n = 57) was not statistically significant. The peripheral one third of the iris tended to be thicker in all quadrants of the PACS eyes, although the difference was statistically significant only in the superior quadrant (P = 0.008). No significant differences were found in the qualitative classifications of iris insertion, iris angulation, ciliary body size, and ciliary process position. The findings were similar when compared with the control group of eyes with wide angles in all quadrants. Conclusions. Basal iris thickness seems to be more relevant to narrow angle configuration than to overall iris thickness. Otherwise, the anterior rotation and size of the ciliary body, the iris insertion, and the overall iris thickness are comparable in narrow- and wide-angle eyes. PMID:19834039

Wake Closure Characteristics and Afterbody Heating on a Mars Sample Return Orbiter

NASA Technical Reports Server (NTRS)

Horvath, Thomas J.; Cheatwood, McNeil F.; Wilmoth, Richard G.; Alter, Stephen J.

2002-01-01

Aeroheating wind-tunnel tests were conducted on a 0.028 scale model of an orbiter concept considered for a possible Mars sample return mission. The primary experimental objectives were to characterize hypersonic near wake closure and determine if shear layer impingement would occur on the proposed orbiter afterbody at incidence angles necessary for a Martian aerocapture maneuver. Global heat transfer mappings, surface streamline patterns, and shock shapes were obtained in the NASA Langley 20-Inch Mach 6 Air and CF4 Tunnels for post-normal shock Reynolds numbers (based on forebody diameter) ranging from 1,400 to 415,000, angles of attack ranging from -5 to 10 degrees at 0, 3, and 6 degree sideslip, and normal-shock density ratios of 5 and 12. Laminar, transitional, and turbulent shear layer impingement on the cylindrical afterbody was inferred from the measurements and resulted in a localized heating maximum that ranged from 40 to 75 percent of the reference forebody stagnation point heating. Comparison of laminar heating prediction to experimental measurement along the orbiter afterbody highlight grid alignment challenges associated with numerical simulation of three- dimensional separated wake flows. Predicted values of a continuum breakdown parameter revealed significant regions of non-continuum flow downstream of the flow separation at the MSRO shoulder and in the region of the reattachment shock on the afterbody. The presence of these regions suggest that the Navier-Stokes predictions at the laminar wind-tunnel condition may encounter errors in the numerical calculation of the wake shear layer development and impingement due to non-continuum effects.

Variants in Nebulin (NEB) Are Linked to the Development of Familial Primary Angle Closure Glaucoma in Basset Hounds

PubMed Central

Ahram, Dina F.; Grozdanic, Sinisa D.; Kecova, Helga; Henkes, Arjen; Collin, Rob W. J.; Kuehn, Markus H.

2015-01-01

Several dog breeds are susceptible to developing primary angle closure glaucoma (PACG), which suggests a genetic basis for the disease. We have identified a four-generation Basset Hound pedigree with characteristic autosomal recessive PACG that closely recapitulates PACG in humans. Our aim is to utilize gene mapping and whole exome sequencing approaches to identify PACG-causing sequence variants in the Basset. Extensive clinical phenotyping of all pedigree members was conducted. SNP-chip genotyping was carried out in 9 affected and 15 unaffected pedigree members. Two-point and multipoint linkage analyses of genome-wide SNP data were performed using Superlink-Online SNP-1.1 and a locus was mapped to chromosome 19q with a maximum LOD score of 3.24. The locus contains 12 Ensemble predicted canine genes and is syntenic to a region on chromosome 2 in the human genome. Using exome-sequencing analysis, a possibly damaging, non-synonymous variant in the gene Nebulin (NEB) was found to segregate with PACG which alters a phylogenetically conserved Lysine residue. The association of this variants with PACG was confirmed in a secondary cohort of unrelated Basset Hounds (p = 3.4 × 10-4, OR = 15.3 for homozygosity). Nebulin, a protein that promotes the contractile function of sarcomeres, was found to be prominently expressed in the ciliary muscles of the anterior segment. Our findings may provide insight into the molecular mechanisms that underlie PACG. The phenotypic similarities of disease presentation in dogs and humans may enable the translation of findings made in this study to patients with PACG. PMID:25938837

Variants in Nebulin (NEB) Are Linked to the Development of Familial Primary Angle Closure Glaucoma in Basset Hounds.

PubMed

Ahram, Dina F; Grozdanic, Sinisa D; Kecova, Helga; Henkes, Arjen; Collin, Rob W J; Kuehn, Markus H

2015-01-01

Several dog breeds are susceptible to developing primary angle closure glaucoma (PACG), which suggests a genetic basis for the disease. We have identified a four-generation Basset Hound pedigree with characteristic autosomal recessive PACG that closely recapitulates PACG in humans. Our aim is to utilize gene mapping and whole exome sequencing approaches to identify PACG-causing sequence variants in the Basset. Extensive clinical phenotyping of all pedigree members was conducted. SNP-chip genotyping was carried out in 9 affected and 15 unaffected pedigree members. Two-point and multipoint linkage analyses of genome-wide SNP data were performed using Superlink-Online SNP-1.1 and a locus was mapped to chromosome 19q with a maximum LOD score of 3.24. The locus contains 12 Ensemble predicted canine genes and is syntenic to a region on chromosome 2 in the human genome. Using exome-sequencing analysis, a possibly damaging, non-synonymous variant in the gene Nebulin (NEB) was found to segregate with PACG which alters a phylogenetically conserved Lysine residue. The association of this variants with PACG was confirmed in a secondary cohort of unrelated Basset Hounds (p = 3.4 × 10-4, OR = 15.3 for homozygosity). Nebulin, a protein that promotes the contractile function of sarcomeres, was found to be prominently expressed in the ciliary muscles of the anterior segment. Our findings may provide insight into the molecular mechanisms that underlie PACG. The phenotypic similarities of disease presentation in dogs and humans may enable the translation of findings made in this study to patients with PACG.

Cost Analysis of Cerebrospinal Fluid Leaks and Cerebrospinal Fluid Leak Prevention in Patients Undergoing Cerebellopontine Angle Surgery.

PubMed

Chern, Alexander; Hunter, Jacob B; Bennett, Marc L

2017-01-01

To determine if cranioplasty techniques following translabyrinthine approaches to the cerebellopontine angle are cost-effective. Retrospective case series. One hundred eighty patients with available financial data who underwent translabyrinthine approaches at a single academic referral center between 2005 and 2015. Cranioplasty with a dural substitute, layered fat graft, and a resorbable mesh plate secured with screws Main Outcome Measures: billing data was obtained for each patient's hospital course for translabyrinthine approaches and postoperative cerebrospinal fluid (CSF) leaks. One hundred nineteen patients underwent translabyrinthine approaches with an abdominal fat graft closure, with a median cost of $25759.89 (range, $15885.65-$136433.07). Sixty-one patients underwent translabyrinthine approaches with a dural substitute, abdominal fat graft, and a resorbable mesh for closure, with a median cost of $29314.97 (range, $17674.28-$111404.55). The median cost of a CSF leak was $50401.25 (range, $0-$384761.71). The additional cost of a CSF leak when shared by all patients who underwent translabyrinthine approaches is $6048.15. The addition of a dural substitute and a resorbable mesh plate after translabyrinthine approaches reduced the CSF leak from 12 to 1.9%, an 84.2% reduction, and a median savings per patient of $2932.23. Applying our cohort's billing data to previously published cranioplasty techniques, costs, and leak rate improvements after translabyrinthine approaches, all techniques were found to be cost-effective. Resorbable mesh cranioplasty is cost-effective at reducing CSF leaks after translabyrinthine approaches. Per our billing data and achieving the same CSF leak rate, cranioplasty costs exceeding $5090.53 are not cost-effective.

Monsoon and primary acute angle closure in malaysia.

PubMed

Ch'ng, T W; Mosavi, S A A; Noor Azimah, A A; Azlan, N Z; Azhany, Y; Liza-Sharmini, A T

2013-10-01

Acute angle closure (AAC) without prompt treatment may lead to optic neuropathy. Environmental factor such as climate change may precipitate pupillary block, the possible mechanism of AAC. To determine the association of northeast monsoon and incidence of AAC in Malaysia. A retrospective study was conducted on AAC patients admitted to two main tertiary hospitals in Kelantan, Malaysia between January 2001 and December 2011. The cumulative number of rainy day, amount of rain, mean cloud cover and 24 hours mean humidity at the estimated day of attack were obtained from the Department of Meteorology, Malaysia. A total 73 cases of AAC were admitted with mean duration of 4.1SD 2.0 days. More than half have previous history of possibility of AAC. There was higher incidence of AAC during the northeast monsoon (October to March). There was also significant correlation of number of rainy day (r=0.718, p<0.001), amount of rain (r=0.587, p<0.001), cloud cover (r=0.637, p<0.001), mean daily global radiation (r=- 0.596, P<0.001), 24 hours mean temperature (r=-0.298, p=0.015) and 24 hours mean humidity (r=0.508, p<0.001) with cumulative number of admission for AAC for 12 calendar months. Higher incidence of AAC during northeast monsoon suggested the effect of climate as the potential risk factor. Prompt treatment to arrest pupillary block and reduction of the intraocular pressure is important to prevent potential glaucomatous damage. Public awareness of AAC and accessibility to treatment should be part of preparation to face the effect of northeast monsoon.

[Angle-closure glaucoma secondary to nonspecific orbital inflammatory: case report].

PubMed

Násser, Luciano Sólia; Liendo da Costa, Vera Lucia; Taniguchi, Marcel Papa; Bolanho, Anamaria; Petrilli, Ana Maria Noriega

2007-01-01

The nonspecific orbital inflammatory presents several clinical forms. When it evolves the posterior segment of the eye, usually by contiguity, it can lead to serious damage to vision functions. Posterior scleritis causes permanent damage to the vision and rarely progresses to acute glaucoma. E.N., a 24-year-old black man, complained of pain in the left eye (OS) for ten days, with low visual acuity, malaise, nauseas and vomiting. On ophthalmologic examination, he presented proptosis, restricted eye movements and edema on the upper left eyelid. Best-corrected visual acuity was 20/20 in OD and counting fingers at 1.5m in OS. The intraocular pressure was 14 mmHg in OD and 34 mmHg in OS. The biomicroscopy presented in OS conjunctival hyperemia cornea with keratic precipitates, shallow anterior chamber with cells and flare 2+. Gonioscopy in OS showed angle-closure of 360 masculine. The ophthalmoscopic examination revealed increased vascular tortuosity and posterior pole edema. Treatment for acute glaucoma was initiated and complementary tests were ordered. Ocular ultrasonography and orbit computerized tomography showed a diffuse thickening of the ocular wall and extrinsic muscles. Other tests were normal. The presumptive diagnosis was acute nonspecific orbital inflammation affecting the ocular bulb posterior segment together with acute glaucoma. He initiated on prednisone 60 mg/day PO. After two weeks of systemic corticotherapy, the patient was asymptomatic, with evident regression of proptosis and scleritis and normal intraocular pressure (11 mmHg in AU). Although not very frequent, acute glaucoma may be present in orbital inflammatory process and should be treated with systemic corticotherapy and topical medication.

The Philadelphia Glaucoma Detection and Treatment Project

PubMed Central

Waisbourd, Michael; Pruzan, Noelle L.; Johnson, Deiana; Ugorets, Angela; Crews, John E.; Saaddine, Jinan B.; Henderer, Jeffery D.; Hark, Lisa A.; Katz, L. Jay

2016-01-01

Purpose To evaluate the detection rates of glaucoma-related diagnoses and the initial treatments received in the Philadelphia Glaucoma Detection and Treatment Project, a community-based initiative aimed at improving the detection, treatment, and follow-up care of individuals at risk for glaucoma. Design Retrospective analysis. Participants A total of 1649 individuals at risk for glaucoma who were examined and treated in 43 community centers located in underserved communities of Philadelphia. Methods Individuals were enrolled if they were African American aged ≥50 years, were any other adult aged ≥60 years, or had a family history of glaucoma. After attending an informational glaucoma workshop, participants underwent a targeted glaucoma examination including an ocular, medical, and family history; visual acuity testing, intraocular pressure (IOP) measurement, and corneal pachymetry; slit-lamp and optic nerve examination; automated visual field testing; and fundus color photography. If indicated, treatments included selective laser trabeculoplasty (SLT), laser peripheral iridotomy (LPI), or IOP-lowering medications. Follow-up examinations were scheduled at the community sites after 4 to 6 weeks or 4 to 6 months, depending on the clinical scenario. Main Outcome Measures Detection rates of glaucoma-related diagnoses and types of treatments administered. Results Of the 1649 individuals enrolled, 645 (39.1%) received a glaucoma-related diagnosis; 20.0% (n = 330) were identified as open-angle glaucoma (OAG) suspects, 9.2% (n = 151) were identified as having narrow angles (or as a primary angle closure/suspect), and 10.0% (n = 164) were diagnosed with glaucoma, including 9.0% (n = 148) with OAG and 1.0% (n = 16) with angle-closure glaucoma. Overall, 39.0% (n = 64 of 164) of those diagnosed with glaucoma were unaware of their diagnosis. A total of 196 patients (11.9%) received glaucoma-related treatment, including 84 (5.1%) who underwent LPI, 13 (0.8%) who underwent SLT, and 103 (6.2%) who were prescribed IOP-lowering medication. Conclusions Targeting individuals at risk for glaucoma in underserved communities in Philadelphia yielded a high detection rate (39.1%) of glaucoma-related diagnoses. Providing examinations and offering treatment, including first-line laser procedures, at community-based sites providing services to older adults are effective to improve access to eye care by underserved populations. PMID:27221736

Clinical verification of a theory for predicting side branch stenosis after main vessel stenting in coronary bifurcation lesions.

PubMed

Vassilev, Dobrin; Gil, Robert

2008-12-01

To verify in a clinical scenario a theory for predicting side branch (SB) stenosis after main vessel stent implantation in coronary bifurcation lesions. Many unresolved issues remain regarding SB compromise when the parent vessel is stented. Bifurcation lesions (all Medina types) were subjected to angiographic analysis to determine the angle, defined as alpha, between the axes of the parent vessel and the SB. Using the prediction that the percent diameter stenosis (%DS) is equal to the cosine of angle alpha and relating it to a formula to determine the minimal lumen diameter (MLD) led to the following equation: MLD = ds x (1 -cos alpha); ds refers to the diameter of the SB. The predicted and observed SB stenosis values following angiography were compared. Fifty-two patients with 57 lesions were included in the analysis. Patient demographics and characteristics were similar to those in previous studies. There was a high coefficient of determination between the predicted and observed values of %DS (r(2)= 0.82, P < 0.001) and MLD (r(2)= 0.86, P < 0.001). We determined a cutoff value of 70% for predicted %DS for SB closure. When using multivariate regression analysis, the only predictor of SB ostial stenosis after stenting was alpha angle, whereas the predictors of MLD included the angle alpha and the RVD of the SB. Our analysis shows that the most powerful independent predictor of SB compromise is a new variable angle alpha.

Glaucoma and clinical characteristics in Vietnamese Americans.

PubMed

Peng, Pai-Huei; Manivanh, Richard; Nguyen, Ngoc; Weinreb, Robert N; Lin, Shan C

2011-08-01

To assess the proportions of glaucoma types and clinical characteristics in Vietnamese Americans in a single-center, retrospective study. Medical charts of Vietnamese-American patients who visited a single private practice in Northern California from 1998-2007 were reviewed. The main outcome measures included the distribution and characteristics of glaucoma types, and clinical parameters associated with the presence of various glaucomas. Data from 2247 patients aged 18-98 years were reviewed. Glaucoma was determined for 305 patients (13.6%). Among this group, 54.8% had primary open-angle glaucoma (POAG), 26.9% had primary angle-closure glaucoma (PACG), 13.4% had mixed mechanism glaucoma (MMG), and 4.9% had secondary glaucoma. In the MMG group (41 patients), 27 patients who initially had open angles developed narrow angles and underwent laser peripheral iridotomy (LPI) with a mean follow up of 6.4 years from the time of iridotomy. The other 13 patients had glaucoma progression with open angles after LPI. One POAG patient had neovascular glaucoma due to retinal vein occlusion several years later. Compared to the PACG group, the MMG group had significantly lower baseline intraocular pressure (25.0 vs. 20.2 mmHg, p = 0.007) but with no difference in biometry. POAG is the major type of glaucoma in this clinic-based Vietnamese population. However, Vietnamese appear to have a relatively higher proportion of PACG than Caucasians and those of African descent. It is recommended that gonioscopy be part of the regular eye check-up for adult Vietnamese patients.

Clear-sky shortwave radiative closure for the Cabauw Baseline Surface Radiation Network site, the Netherlands

NASA Astrophysics Data System (ADS)

Wang, P.; Knap, W. H.; Kuipers Munneke, P.; Stammes, P.

2009-04-01

During the last two decades, several attempts have been made to achieve agreement between clear-sky shortwave broadband irradiance models and surface measurements of direct and diffuse irradiance. In general, models and measurements agreed well for the direct component but closing the gap for diffuse irradiances remained problematic. The number of studies reporting a satisfactory degree of closure for both direct and diffuse irradiance is still limited, which motivated us to perform the study presented here. In this paper a clear-sky shortwave closure analysis is presented for the Baseline Surface Radiation Network (BSRN) site of Cabauw, the Netherlands (51.97 °N, 4.93 °E). The analysis is based on an exceptional period of fine weather in the first half of May 2008 during the Intensive Measurement Period At the Cabauw Tower (IMPACT), an activity of the European Integrated project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI). Although IMPACT produced a wealth of data, it was decided to conduct the closure analysis using routine measurements only, provided by BSRN and the Aerosol Robotic Network (AERONET), completed with radiosonde obervations. The rationale for this pragmatic approach is the possibility of applying the method presented here to other periods and (BSRN) sites, where routine measurements are readily available, without having to deal with the investments and restrictions of an intensive observation period. The analysis is based on a selection of 72 comparisons on 6 days between BSRN measurements and Doubling Adding KNMI (DAK) model simulations of direct, diffuse, and global irradiance. The data span a wide range of aerosol properties, water vapour columns, and solar zenith angles. The model input consisted of operational Aerosol Robotic Network (AERONET) aerosol products and radiosonde data. On the basis of these data excellent closure was obtained: the mean differences between model and measurements are 2 W/m2 (+0.2%) for direct irradiance, 1 W/m2 (+0.8%) for diffuse irradiance, and 2 W/m2 (+0.3%) for global irradiance.

Revealing the sub-AU asymmetries of the inner dust rim in the disk around the Herbig Ae star R Coronae Austrinae

NASA Astrophysics Data System (ADS)

Kraus, S.; Hofmann, K.-H.; Malbet, F.; Meilland, A.; Natta, A.; Schertl, D.; Stee, P.; Weigelt, G.

2009-12-01

Context: Unveiling the structure of the disks around intermediate-mass pre-main-sequence stars (Herbig Ae/Be stars) is essential for our understanding of the star and planet formation process. In particular, models predict that in the innermost AU around the star, the dust disk forms a “puffed-up” inner rim, which should result in a strongly asymmetric brightness distribution for disks seen under intermediate inclination. Aims: Our aim is to constrain the sub-AU geometry of the inner disk around the Herbig Ae star R CrA and search for the predicted asymmetries. Methods: Using the VLTI/AMBER long-baseline interferometer, we obtained 24 near-infrared (H- and K-band) spectro-interferometric observations on R CrA. Observing with three telescopes in a linear array configuration, each data set samples three equally spaced points in the visibility function, providing direct information about the radial intensity profile. In addition, the observations cover a wide position angle range (~97°), also probing the position angle dependence of the source brightness distribution. Results: In the derived visibility function, we detect the signatures of an extended (Gaussian FWHM ~ 25 mas) and a compact component (Gaussian FWHM ~ 5.8 mas), with the compact component contributing about two-thirds of the total flux (both in H- and K-band). The brightness distribution is highly asymmetric, as indicated by the strong closure phases (up to ~40°) and the detected position angle dependence of the visibilities and closure phases. To interpret these asymmetries, we employ various geometric as well as physical models, including a binary model, a skewed ring model, and a puffed-up inner rim model with a vertical or curved rim shape. For the binary and vertical rim model, no acceptable fits could be obtained. On the other hand, the skewed ring model and the curved puffed-up inner rim model allow us to simultaneously reproduce the measured visibilities and closure phases. From these models we derive the location of the dust sublimation radius (~0.4 AU), the disk inclination angle (~35°), and a north-south disk orientation (PA ~ 180-190°). Our curved puffed-up rim model can reproduce reasonably well the interferometric observables and the SED and suggests a luminosity of ~29 L⊙ and the presence of relatively large (⪆1.2 μm) Silicate dust grains. Our study also reveals discrepancies between the measured interferometric observables and the puffed-up inner rim models, providing important constraints for future refinements of these theoretical models. Perpendicular to the disk, two bow shock-like structures appear in the associated reflection nebula NGC 6729, suggesting that the detected sub-AU size disk is the driving engine of a large-scale outflow. Conclusions: Detecting, for the first time, strong non-localized asymmetries in the inner regions of a Herbig Ae disk, our study supports the existence of a puffed-up inner rim in YSO disks. Based on observations made with ESO telescopes at the La Silla Paranal Observatory under programme IDs 079.D-0370(A), 081.C-0272(A,B,C), and 081.C-0321(A).

General design method for three-dimensional potential flow fields. 1: Theory

NASA Technical Reports Server (NTRS)

Stanitz, J. D.

1980-01-01

A general design method was developed for steady, three dimensional, potential, incompressible or subsonic-compressible flow. In this design method, the flow field, including the shape of its boundary, was determined for arbitrarily specified, continuous distributions of velocity as a function of arc length along the boundary streamlines. The method applied to the design of both internal and external flow fields, including, in both cases, fields with planar symmetry. The analytic problems associated with stagnation points, closure of bodies in external flow fields, and prediction of turning angles in three dimensional ducts were reviewed.

Prediction and measurement of direct-normal solar irradiance: A closure experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halthore, R.N.; Schwartz, S.E.; Michalsky, J.J.

1997-03-01

Direct-normal solar irradiance (DNSI), the total energy in the solar spectrum incident on a plane perpendicular to the Sun`s direction on a unit area at the earth`s surface in unit time, depends only on the atmospheric extinction of sunlight without regard to the details of extinction--whether absorption or scattering. Here the authors describe a set of closure experiments performed in north-central Oklahoma, wherein measured atmospheric composition is input to a radiative transfer model, MODTRAN-3, to predict DNSI, which is then compared to measured values. Thirty six independent comparisons are presented; the agreement between predicted and measured values falls within themore » combined uncertainties in the prediction (2%) and measurement (0.2%) albeit with a slight bias ({approximately} 1% overprediction) that is independent of the solar zenith angle. Thus these results establish the adequacy of current knowledge of the solar spectrum and atmospheric extinction as embodied in MODTRAN-3 for use in climate models. An important consequence is the overwhelming likelihood that the atmospheric clear-sky absorption is accurately described to within comparable uncertainties.« less

Prediction and measurement of direct-normal solar irradiance: A closure experiment

NASA Technical Reports Server (NTRS)

Halthore, R. N.; Schwartz, S. E.; Michalsky, J. J.; Anderson, G. P.; Ferrare, R. A.; Ten Brink, H. M.

1997-01-01

Direct-Normal Solar Irradiance (DNSI), the total energy in the solar spectrum incident on a plane perpendicular to the Sun's direction on a unit area at the earth's surface in unit time, depends only on the atmospheric extinction of sunlight without regard to the details of extinction-whether absorption or scattering. Here the authors describe a set of closure experiments performed in north-central Oklahoma, wherein measured atmospheric composition is input to a radiative transfer model, MODTRAN-3, to predict DNSI, which is then compared to measured values. Thirty six independent comparisons are presented; the agreement between predicted and measured values falls within the combined uncertainties in the prediction (2%) and measurement (0.2%) albeit with a slight bias ((approximately) 1% overprediction) that is independent of the solar zenith angle. Thus these results establish the adequacy of current knowledge of the solar spectrum and atmospheric extinction as embodied in MODTRAN-3 for use in climate models. An important consequence is the overwhelming likelihood that the atmospheric clear-sky absorption is accurately described to within comparable uncertainties.

Closed geometric models in medical applications

NASA Astrophysics Data System (ADS)

Jagannathan, Lakshmipathy; Nowinski, Wieslaw L.; Raphel, Jose K.; Nguyen, Bonnie T.

1996-04-01

Conventional surface fitting methods give twisted surfaces and complicates capping closures. This is a typical character of surfaces that lack rectangular topology. We suggest an algorithm which overcomes these limitations. The analysis of the algorithm is presented with experimental results. This algorithm assumes the mass center lying inside the object. Both capping closure and twisting are results of inadequate information on the geometric proximity of the points and surfaces which are proximal in the parametric space. Geometric proximity at the contour level is handled by mapping the points along the contour onto a hyper-spherical space. The resulting angular gradation with respect to the centroid is monotonic and hence avoids the twisting problem. Inter-contour geometric proximity is achieved by partitioning the point set based on the angle it makes with the respective centroids. Avoidance of capping complications is achieved by generating closed cross curves connecting curves which are reflections about the abscissa. The method is of immense use for the generation of the deep cerebral structures and is applied to the deep structures generated from the Schaltenbrand- Wahren brain atlas.

Effect of Compressive Mode I on the Mixed Mode I/II Fatigue Crack Growth Rate of 42CrMo4

NASA Astrophysics Data System (ADS)

Heirani, Hasan; Farhangdoost, Khalil

2018-01-01

Subsurface cracks in mechanical contact loading components are subjected to mixed mode I/II, so it is necessary to evaluate the fatigue behavior of materials under mixed mode loading. For this purpose, fatigue crack propagation tests are performed with compact tension shear specimens for several stress intensity factor (SIF) ratios of mode I and mode II. The effect of compressive mode I loading on mixed mode I/II crack growth rate and fracture surface is investigated. Tests are carried out for the pure mode I, pure mode II, and two different mixed mode loading angles. On the basis of the experimental results, mixed mode crack growth rate parameters are proposed according to Tanaka and Richard with Paris' law. Results show neither Richard's nor Tanaka's equivalent SIFs are very useful because these SIFs depend strongly on the loading angle, but Richard's equivalent SIF formula is more suitable than Tanaka's formula. The compressive mode I causes the crack closure, and the friction force between the crack surfaces resists against the crack growth. In compressive loading with 45° angle, d a/d N increases as K eq decreases.

Iridoschisis: high frequency ultrasound imaging. Evidence for a genetic defect?

PubMed Central

Danias, J; Aslanides, I M; Eichenbaum, J W; Silverman, R H; Reinstein, D Z; Coleman, D J

1996-01-01

AIMS: To elucidate changes in the anatomy of the anterior chamber associated with iridoschisis, a rare form of iris atrophy, and their potential contribution to angle closure glaucoma. METHODS: Both eyes of a 71-year-old woman with bilateral iridoschisis and fibrous dysplasia and her asymptomatic 50-year-old daughter were scanned with a very high frequency (50 MHz) ultrasound system. RESULTS: The symptomatic patient exhibited diffuse changes in the iris stoma with an intact posterior iris pigmented layer in both eyes. These changes were clinically compatible with the lack of iris transillumination defects. Additionally, iris bowing with a resultant narrowing of the angle occurred. The asymptomatic daughter showed discrete, but less severe iris stromal changes. CONCLUSION: This is the first detailed study of high frequency ultrasonic imaging of the iris in iridoschisis. The observed structural changes suggest angle narrowing by forward bowing of the anterior iris stroma may be a mechanism of IOP elevation in this condition. The ultrasonic detection of iris changes in the asymptomatic daughter of the symptomatic patient and the association of iridoschisis with fibrous dysplasia suggest a possible genetic component in the pathogenesis of this condition. Images PMID:9059271

Light distribution in plant canopies: A comparison between 1-D multi-layer modeling approach and 3-D ray tracing

NASA Astrophysics Data System (ADS)

Srinivasan, V.; Yiwen, X.; Ellis, A.; Christensen, A.; Borkiewic, K.; Cox, D.; Hart, J.; Long, S.; Marshall-Colon, A.

2016-12-01

The distribution of absorbed solar radiation in the photosynthetically active region wavelength (PAR) within plant canopies plays a critical role in determining photosynthetic carbon uptake and its associated transpiration. The vertical distribution of leaf area, leaf angles, leaf absorptivity and reflectivity within the canopy, affect the distribution of PAR absorbed throughout the canopy. While the upper canopy sunlit leaves absorb most of the incoming PAR and hence contribute most towards total canopy carbon uptake, the lower canopy shaded leaves which receive mostly lower intensity diffuse PAR make significant contributions towards plant carbon uptake. Most detailed vegetation models use a 1-D vertical multi-layer approach to model the sunlight and shaded canopy leaf fractions, and quantify the direct and diffuse radiation absorbed by the respective leaf fractions. However, this approach is only applicable under canopy closure conditions, and furthermore it fails to accurately capture the effects of diurnally varying leaf angle distributions in some plant canopies. Here, we show by using a 3-D ray tracing model which uses an explicit 3-D canopy structure that enforces no conditions about canopy closure, that the effects of diurnal variation of canopy leaf angle distributions better match with observed data. Our comparative analysis performed on soybean crop canopies between 3-D ray tracing model and the multi-layer model shows that the distribution of absorbed direct PAR is not exponential while, the distribution of absorbed diffuse PAR radiation within plant canopies is exponential. These results show the multi-layer model to significantly over-predict canopy PAR absorbed, and in turn significantly overestimate photosynthetic carbon uptake by up to 13% and canopy transpiration by 7% under mid-day sun conditions as verified through our canopy chamber experiments. Our results indicate that current detailed 1-D multi-layer canopy radiation attenuation models significantly over predict canopy radiation absorption and its associated canopy photosynthetic and transpiration fluxes, and use of a 3-D ray tracing model provides more realistic predictions of leaf canopy integrated fluxes of carbon and water.

Surgical peripheral iridectomy via a clear-cornea phacoemulsification incision for pupillary block following cataract surgery in acute angle closure.

PubMed

Fang, Aiwu; Wang, Peijuan; He, Rui; Qu, Jia

2018-05-18

To describe a technique of surgical peripheral iridectomy via a clear-cornea tunnel incision to prevent or treat pupillary block following phacoemulsification. Description of technique and retrospective description results in 20 eyes of 20 patients with acute angle closure with coexisting visually significant cataract undergoing phacoemulsification considered at risk of postoperative papillary block as well as two pseudo-phakic eyes with acute postoperative pupillary-block. Following phacoemulsification and insertion of an intraocular lens, a needle with a bent tip was inserted behind the iris through the corneal tunnel incision. A blunt iris repositor was introduced through the paracentesis and placed above the iris to exert posterior pressure and create a puncture. The size of the puncture was enlarged using scissors. For postoperative pupillary block the same technique was carried out through the existing incisions created for phacoemulsification. Peripheral iridectomy was successfully created in all 22 eyes. At a mean follow-up of 18.77 ± 9.72 months, none of the iridectomies closed or required enlargement. Two eyes had mild intraoperative bleeding and one eye a small Descemet's detachment that did not require intervention. No clinically significant complications were observed. Visual acuity and IOP improved or was maintained in all patients. The incidence of pupillary block in our hospital was 0.09% overall, 0.6% in diabetics and 3.5% in those with diabetic retinopathy. This technique of peripheral iridectomy via the cornea tunnel incision can be safely used during phacoemulsification in eyes at high risk of pupillary block or in the treatment of acute postoperative pupillary-block after cataract surgery. The technique is likely to be especially useful in brown iris, or if a laser is not available.

Anterior capsule relaxing incisions with neodymium:YAG laser for patients at high-risk for anterior capsule contraction.

PubMed

Hayashi, Ken; Yoshida, Motoaki; Hirata, Akira; Hayashi, Hideyuki

2011-01-01

To examine the effect of anterior capsule relaxing incisions created with a neodymium:YAG (Nd:YAG) laser on prevention of anterior capsule contraction after cataract surgery in high-risk patients. Hayashi Eye Hospital, Fukuoka, Japan. Randomized masked clinical trials. Patients at high risk for anterior capsule contraction had anterior capsule relaxing incisions in either eye 3 days postoperatively. The anterior capsule opening was measured using a Scheimpflug videophotography system (EAS-1000) immediately and 1, 3, and 6 months after capsulotomy, and the percentage reduction in area was calculated. The degree of intraocular lens (IOL) decentration and tilt, posterior capsule opacification (PCO), and other complications were also assessed. Of the 84 patients included, 30 had primary angle closure, 28 had pseudoexfoliation, and 26 had diabetic retinopathy. There was no significant difference in the mean opening area between fellow eyes at baseline. In patients with primary angle closure, the area was significantly greater and the percentage reduction in area was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0428). In patients with pseudoexfoliation or diabetic retinopathy, the percentage reduction was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0493), although there was no significant difference in area. No significant difference was found in IOL decentration or tilt, PCO, or incidence of other complications. Neodymium:YAG laser anterior capsule relaxing incisions in the early period after cataract surgery were effective in preventing anterior capsule contraction in high-risk patients and had no adverse effects. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

[Glaucoma and retinal surgery].

PubMed

Müller, M; Geerling, G; Zierhut, M; Klink, T

2010-05-01

In the therapeutic approach to complex glaucomas different initial situations were considered: pre-existing glaucoma, induction of glaucoma after vitreoretinal surgery and antiglaucomatous procedures. In pre-existing glaucoma and after filtering surgery maintenance of the filtering bleb requires a vitreoretinal approach for conjunctiva preservation with techniques such as pneumatic retinopexy or small gauge vitrectomy. After vitreoretinal surgery an increase in intraocular pressure (IOP) is common. Secondary glaucoma may occur after scleral buckling and after vitrectomy with or without gas or silicone oil tamponade as well as after application of steroids. Angle closure glaucoma after scleral buckling develops because of congestion and anterior rotation of the ciliary body. Vitreous tamponades with expansive or saturated gases may cause angle-closure glaucoma with or without pupillary blockage and may critically shorten ocular perfusion. Postoperative checks, immediate action and a ban on boarding aircraft over the period of intraocular gas tamponade prevent permanent damage to the eye. The majority of secondary glaucomas can effectively be controlled by topical medication and adequate postoperative posture of the patient. Besides the temporary use of systemic antiglaucomatous medication or laser therapy, very rarely in cases of massive swelling or overfill, a direct intervention, such as partial gas or silicone oil removal is required. A prophylactic inferior peripheral iridectomy prevents pupillary blockage in aphakic eyes with intraocular tamponade. In cases of heavy silicone oil use, the peripheral iridectomy is placed in the superior position. Nd:YAG laser application will regulate IOP in cases of occlusion. Secondary glaucoma due to silicone oil emulsification overload is treated by trabecular meshwork aspiration and lavage. In refractory glaucoma repetitive cyclophotocoagulation and drainage implants represent an approved method for long-term IOP regulation. The underlying cause of secondary glaucoma after vitreoretinal surgery is often multifactorial in nature and may benefit from an exact analysis for an adequate and successful treatment regimen.

The effects of methylphenidate on refraction and anterior segment parameters in children with attention deficit hyperactivity disorder.

PubMed

Larrañaga-Fragoso, Paula; Noval, Susana; Rivero, José C; Boto-de-los-Bueis, Ana

2015-08-01

Methylphenidate hydrochloride is used as first-line treatment for attention deficit hyperactivity disorder (ADHD). However, there is concern that this treatment may be associated with increased risk of angle closure glaucoma and disturbance of ocular refraction. The aim of this study was to investigate the effects of methylphenidate treatment on refraction, intraocular pressure, and the anterior chamber in children with ADHD. In this prospective pilot study, children diagnosed with ADHD were examined before the start of methylphenidate treatment and again 3 and 9 months after the start of treatment. Ocular examination before and after cycloplegia was performed at each visit, including Pentacam imaging of the anterior chamber. A total of 14 patients (mean age, 11 years) were recruited. The mean visual acuity, sphere, spherical equivalent refraction, intraocular pressure, and cup:disk ratio did not change significantly after the start of treatment. The anterior chamber depth after cycloplegia decreased significantly between baseline and 9 months, from 3.26 ± 0.22 mm to 3.24 ± 0.23 mm in the right eye (P = 0.037) and from 3.28 ± 0.22 mm to 3.25 ± 0.24 mm in the left eye (P = 0.001). Methylphenidate does not seem to affect refraction in most children with ADHD. After 9 months of treatment, however, there was a reduction in the anterior chamber depth, which has been described as a powerful predictor of angle closure glaucoma. Further investigation of the potential ocular side effects of methylphenidate treatment is warranted. Copyright © 2015 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Cost-effectiveness of Phacoemulsification Versus Combined Phacotrabeculectomy for Treating Primary Angle Closure Glaucoma.

PubMed

Chan, Poemen P; Li, Emmy Y; Tsoi, Kelvin K F; Kwong, Yolanda Y; Tham, Clement C

2017-10-01

The purpose of this study is to compare the cost effectiveness of phacoemulsification and combined phacotrabeculectomy for lowering intraocular pressure (IOP) in primary angle closure glaucoma (PACG) eyes with coexisting cataract. Real-life data of 2 previous randomized control trials that involved 51 medically uncontrolled PACG eyes and 72 medically controlled PACG eyes were utilized to calculate the direct cost of treatment. They were followed-up for 2 years. Cost of preoperative assessments, surgical interventions, additional procedures for managing complications and maintenance of filtration, postoperative follow-up, and cost of medications were considered. Cost data of 3 different regions (The United States, People's Republic of China, and Hong Kong) were used for comparison. The corresponding average costs for treating 1 eye with newly diagnosed PACG by phacoemulsification alone and combined phacotrabeculectomy were US$3479 and US$2439 in the United States, US$1051 and US$861 in China, and US$6856 and US$12087 in Hong Kong. Surgical and medications costs were the 2 key contributors. Combined phacotrabeculectomy was more cost-effective for IOP reduction when calculating with the United States and China cost data, but was less cost-effective when calculating with the Hong Kong cost data. The cost-effectiveness was insensitive to the costs of follow-up visit and investigations, the cost of surgical operations, and the cost of postoperative procedures, but sensitive to the cost fluctuation of medications. Furthermore, for the medically uncontrolled PACG group, phacoemulsification alone became more cost-effective when the cost of medication was reduced by >75%. Combined phacotrabeculectomy is a more cost-effective option for lowering IOP in PACG eyes with coexisting cataract, over a 2-year follow-up period.

Aqueous Humor Levels of TGF-β2 and TNF-α in Indonesian Eyes With Acute Primary Angle Closure.

PubMed

Artini, Widya; Gondhowiardjo, Tjahjono Darminto; Supiandi, Edi S; Tin, Aung

2012-01-01

To measure aqueous humor levels of TGF-β2 and TNF-α in Indonesian eyes with acute primary angle closure (APAC) and to investigate their relationship to response to treatment. A prospective observational study. On presentation, aqueous humor samples were taken from APAC eyes by paracentesis. All APAC eyes then underwent laser peripheral iridotomy (LPI). Two weeks following LPI, trabeculectomy was performed if the intraocular pressure (IOP) was still high. Alternatively, phacoemulsification was performed in cases of normal IOP. Aqueous humor samples were taken again at the time of both surgical procedures. Age-matched cataract patients were included as a control group. Cytokine samples were measured by enzyme-linked immunosorbent assay (ELISA). Forty-three Indonesian APAC subjects were recruited in this study. The mean presenting IOP was 56.4 ± 0.52 mmHg and 53% underwent trabeculectomy. Comparison of the APAC eyes to the control group showed there was a significant difference in the mean levels of TGF-β2 (2007.7 ± 827.2 pg/mL vs 466.1 ± 219.3 pg/mL, p < 0.001) and TNF-α (0.714 ± 0.33 pg/mL vs 0.228 ± 0.16 pg/mL, p < 0.001). There was no significant difference in the presented TGF-β2 and TNF-α levels between the trabeculectomy and phacoemulsification groups (p:0.391 and p:0.494). Between presentation and surgery in the trabeculectomy subgroup, both cytokine levels appeared to be significantly different (p < 0.035 and p < 0.038). This study showed the aqueous humor levels of TGF-β2 and TNF-α appeared high at presentation but decreased subsequently, with no difference detected between groups with persistently high IOP and those with normalized IOP.

Growth plate closure: Apex view on bone scan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giles, P.H.; Trochei, M.; Yeates, K.

1984-01-01

Angular deformities of the extremities in children following premature closure of the growth plate are well known. The deformities depend on the position of an osseus bridge which forms between the epiphysis and metaphysis. Several surgical procedures including resection of the osseus bridge have been described, however, delineation of the site of fusion is difficult to define. The commonest site of growth plate arrest is the distal femoral or proximal tibial growth plate. A new technique using the bone scan has been developed which accurately defines the area and position of these osseus bridges. Two hours after injection of technetiummore » 99m methylene diphosphonate apex views of the affected distal femoral growth plate were performed. The knee was flexed into its smallest angle. Using a pinhole collimator the gamma camera was angled to face the affected growth plate end on. The image was collected onto computer and analysed by: (I) regions of interest over segments of the growth plate to calculate the relative area of total growth plate affected: (II) generating histograms: (III) thresholding or performing isocontours to accentuate abnormal areas. The growth plate is normally uniformly increased when compared to the normal shaft of the bone. Fusion across the plate appears as an area of diminished uptake. The apex view gives a unique functional map of the growth plate such that abnormal areas are displayed, and the site, size and position of osseus fusion obtained. The technique has the potential for determining the metabolic activity of the growth plate before and after surgery. Serial studies will allow assessment of regneration of the plate and reformation of new osseus bridges.« less

Enter the reverend: introduction to and application of Bayes' theorem in clinical ophthalmology.

PubMed

Thomas, Ravi; Mengersen, Kerrie; Parikh, Rajul S; Walland, Mark J; Muliyil, Jayprakash

2011-12-01

Ophthalmic practice utilizes numerous diagnostic tests, some of which are used to screen for disease. Interpretation of test results and many clinical management issues are actually problems in inverse probability that can be solved using Bayes' theorem. Use two-by-two tables to understand Bayes' theorem and apply it to clinical examples. Specific examples of the utility of Bayes' theorem in diagnosis and management. Two-by-two tables are used to introduce concepts and understand the theorem. The application in interpretation of diagnostic tests is explained. Clinical examples demonstrate its potential use in making management decisions. Positive predictive value and conditional probability. The theorem demonstrates the futility of testing when prior probability of disease is low. Application to untreated ocular hypertension demonstrates that the estimate of glaucomatous optic neuropathy is similar to that obtained from the Ocular Hypertension Treatment Study. Similar calculations are used to predict the risk of acute angle closure in a primary angle closure suspect, the risk of pupillary block in a diabetic undergoing cataract surgery, and the probability that an observed decrease in intraocular pressure is due to the medication that has been started. The examples demonstrate how data required for management can at times be easily obtained from available information. Knowledge of Bayes' theorem helps in interpreting test results and supports the clinical teaching that testing for conditions with a low prevalence has a poor predictive value. In some clinical situations Bayes' theorem can be used to calculate vital data required for patient management. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

Low-energy electron scattering from water molecules: A study of angular distributions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gianturco, F.A.; Scialla, S.

1987-12-01

We report quantal calculations of elastic differential and momentum transfercross sections for the scattering of electrons by H/sub 2/O at low and intermediatecollision energies, i.e., from 2 to 20 eV. The fixed-nuclei approximation (FNA) was employed and a single-center expanded (SCE) wave function was used to represent the molecular target. The well-known divergence in the forward direction was corrected via Born closure formulas (see the text) and a parameter-free model, previously tested for methane targets, was used to describe exchange and polarization effects. The present results can be used to adequately describe angular distributions even at very small angles andmore » can be extended beyond the largest angles that have been experimentally measured. The behavior of momentum-transfer cross sections as a function of energy, and the comparison of our results with other static-exchange (SE) calculations, which use an entirely different approach, are presented and discussed.« less

Non-contact high resolution Bessel beam probe for diagnostic imaging of cornea and trabecular meshwork region in eye

NASA Astrophysics Data System (ADS)

Murukeshan, V. M.; Jesmond, Hong Xun J.; Shinoj, V. K.; Baskaran, M.; Tin, Aung

2015-07-01

Primary angle closure glaucoma is a major form of disease that causes blindness in Asia and worldwide. In glaucoma, irregularities in the ocular aqueous outflow system cause an elevation in intraocular pressure (IOP) with subsequent death of retinal ganglion cells, resulting in loss of vision. High resolution visualization of the iridocorneal angle region has great diagnostic value in understanding the disease condition which enables monitoring of surgical interventions that decrease IOP. None of the current diagnostic techniques such as goniophotography, ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (AS-OCT) and RetCam™ can image with molecular specificity and required spatial resolution that can delineate the trabecular meshwork structures. This paper in this context proposes new concepts and methodology using Bessel beams based illumination and imaging for such diagnostic ocular imaging applications. The salient features using Bessel beams instead of the conventional Gaussian beam, and the optimization challenges in configuring the probe system will be illustrated with porcine eye samples.

Enhanced ultrafast relaxation rate in the Weyl semimetal phase of MoTe2 measured by time- and angle-resolved photoelectron spectroscopy

NASA Astrophysics Data System (ADS)

Crepaldi, A.; Autès, G.; Gatti, G.; Roth, S.; Sterzi, A.; Manzoni, G.; Zacchigna, M.; Cacho, C.; Chapman, R. T.; Springate, E.; Seddon, E. A.; Bugnon, Ph.; Magrez, A.; Berger, H.; Vobornik, I.; Kalläne, M.; Quer, A.; Rossnagel, K.; Parmigiani, F.; Yazyev, O. V.; Grioni, M.

2017-12-01

MoTe2 has recently been shown to realize in its low-temperature phase the type-II Weyl semimetal (WSM). We investigated by time- and angle- resolved photoelectron spectroscopy (tr-ARPES) the possible influence of the Weyl points on the electron dynamics above the Fermi level EF, by comparing the ultrafast response of MoTe2 in the trivial and topological phases. In the low-temperature WSM phase, we report an enhanced relaxation rate of electrons optically excited to the conduction band, which we interpret as a fingerprint of the local gap closure when Weyl points form. By contrast, we find that the electron dynamics of the related compound WTe2 is slower and temperature independent, consistent with a topologically trivial nature of this material. Our results shows that tr-ARPES is sensitive to the small modifications of the unoccupied band structure accompanying the structural and topological phase transition of MoTe2.

Linear stapler closure of the pharynx during total laryngectomy: a 15-year experience (from closed technique to semi-closed technique)

PubMed Central

Altissimi, G; Frenguelli, A

2007-01-01

Summary Personal experience in performing linear stapler closure of the pharynx during 70 total laryngectomies is reported. Laryngeal staplers (55 and 60 cm) with an angled handle were used, permitting vertical closure with 19 or 20 metal staples in a double row. A closed technique was initially used, but, over the years, this has gradually been replaced by the semi-closed technique to avoid trapping the suprahyoid part of the epiglottis between the jaws of the stapler. The stapler is inserted below the larynx after having separated it from all muscular and neurovascular connections, and after performing a mini-pharyngotomy at the vallecula epiglottica in order to extract the epiglottis, evert it ventrally and suture it to the hyothyroepiglottic space. The jaws of the stapler are closed and the staples are fired while the flaps of the mini-pharyngotomy are raised above the jaws. The scalpel is inserted above the stapler to remove the larynx. When the stapler is opened, the vertical linear suture of the pharynx is evident and can be examined. This procedure takes only a few minutes to perform. It guarantees a long-term stable watertight closure, dramatically reduces contamination of the operating field by pharyngeal secretions, and permits rapid healing time, greatly lowering patient management costs. In the cases presented here, there was a 1.8% rate of pharyngocutaneous fistulae in patients who were not radiated, whereas the rate was 13.1% in pre-radiated patients. In agreement with the international literature, this procedure does not increase the rate of fistulae and, in fact, it seems to reduce it. Moreover, it is particularly indicated for pre-radiated patients. Nevertheless, the Authors recommend reserving this type of procedure to cases in which, based on meticulous pre-operative assessment by means of endoscopy and imaging, the endolaryngeal site of the tumour has been assessed and there is no need for peri-operative exploration of the pharynx or tongue base. PMID:17883187

Effect of the sinus of valsalva on the closing motion of bileaflet prosthetic heart valves.

PubMed

Ohta, Y; Kikuta, Y; Shimooka, T; Mitamura, Y; Yuhta, T; Dohi, T

2000-04-01

Conventional bileaflet prosthetic mechanical heart valves close passively with backflow. Naturally, the valve has problems associated with closure, such as backflow, water hammer effect, and fracture of the leaflet. On the other hand, in the case of the natural aortic valve, the vortex flow in the sinus of Valsalva pushes the leaflet to close, and the valve starts the closing motion earlier than the prosthetic valve as the forward flow decelerates. This closing mechanism is thought to decrease backflow at valve closure. In this study, we propose a new bileaflet mechanical valve resembling a drawbridge in shape, and the prototype valve was designed so that the leaflet closes with the help of the vortex flow in the sinus. The test valve was made of aluminum alloy, and its closing motion was compared to that of the CarboMedics (CM) valve. Both valves were driven by a computer controlled hydraulic mock circulator and were photographed at 648 frames/s by a high speed charge-coupled device (CCD) camera. Each frame of the valve motion image was analyzed with a personal computer, and the opening angles were measured. The flow rate was set as 5.0 L/min. The system was pulsed with 70 bpm, and the systolic/diastolic ratio was 0.3. Glycerin water was used as the circulation fluid at room temperature, and polystyrene particles were used to visualize the streamline. The model of the sinus of Valsalva was made of transparent silicone rubber. As a result, high speed video analysis showed that the test valve started the closing motion 41 ms earlier than the CM valve, and streamline analysis showed that the test valve had a closing mechanism similar to the natural one with the effect of vortex flow. The structure of the test valve was thought to be effective for soft closure and could solve problems associated with closure.

Percutaneous closure of patent ductus arteriosus in children using amplatzer duct occluder II: relationship between PDA type and risk of device protrusion into the descending aorta.

PubMed

Masri, Samer; El Rassi, Issam; Arabi, Mariam; Tabbakh, Anas; Bitar, Fadi

2015-08-01

To compare the efficacy and safety of Amplatzer Duct Occluder II (ADOII) among the various patent ductus arteriosus (PDA) types, and to assess the association between development of aortic obstruction and the PDA type in terms of measurable parameters as the device angulation and distance of upper end protrusion into the aortic lumen. Retrospective cohort study involving 50 consecutive subjects who underwent ADO II device closure of PDA. The median age and weight at intervention were 13 months (5.5 months to 18 years) and 11 (6-67) kg respectively. The median smallest ductal diameter by angiography was 3.2 (1.9-5.4) mm. Thirty two patients had type A PDA, 5 had type C, 5 had type D, and 8 had type E. Residual shunt was seen in only 1 patient who had a tubular PDA and resolved within 2 months of the procedure. No device embolization or pulmonary side protrusion were noted. There was a 16% aortic protrusion rate. The median distance of protrusion of the upper end of the device into the aortic lumen was 3.1 (0-9) mm and the median angle formed between the aortic end of the device and the PDA take-off was 10.4 (0-80.6) degrees. These latter parameters of aortic obstruction were significantly higher in the non-conical PDA group as compared to the conical PDA. Nevertheless, there was no significant coarctation due to aortic retention disc protrusion. Device closure of PDA using the ADO II is a safe procedure for chosen types of PDA. We demonstrated a novel technique for objective assessment of device protrusion into the descending aorta based on measurable parameters. ADOII device closure of non-conical PDAs warrants closer follow ups. © 2015 Wiley Periodicals, Inc.

Water based on a molecular model behaves like a hard-sphere solvent for a nonpolar solute when the reference interaction site model and related theories are employed

NASA Astrophysics Data System (ADS)

Hayashi, Tomohiko; Oshima, Hiraku; Harano, Yuichi; Kinoshita, Masahiro

2016-09-01

For neutral hard-sphere solutes, we compare the reduced density profile of water around a solute g(r), solvation free energy μ, energy U, and entropy S under the isochoric condition predicted by the two theories: dielectrically consistent reference interaction site model (DRISM) and angle-dependent integral equation (ADIE) theories. A molecular model for water pertinent to each theory is adopted. The hypernetted-chain (HNC) closure is employed in the ADIE theory, and the HNC and Kovalenko-Hirata (K-H) closures are tested in the DRISM theory. We also calculate g(r), U, S, and μ of the same solute in a hard-sphere solvent whose molecular diameter and number density are set at those of water, in which case the radial-symmetric integral equation (RSIE) theory is employed. The dependences of μ, U, and S on the excluded volume and solvent-accessible surface area are analyzed using the morphometric approach (MA). The results from the ADIE theory are in by far better agreement with those from computer simulations available for g(r), U, and μ. For the DRISM theory, g(r) in the vicinity of the solute is quite high and becomes progressively higher as the solute diameter d U increases. By contrast, for the ADIE theory, it is much lower and becomes further lower as d U increases. Due to unphysically positive U and significantly larger |S|, μ from the DRISM theory becomes too high. It is interesting that μ, U, and S from the K-H closure are worse than those from the HNC closure. Overall, the results from the DRISM theory with a molecular model for water are quite similar to those from the RSIE theory with the hard-sphere solvent. Based on the results of the MA analysis, we comparatively discuss the different theoretical methods for cases where they are applied to studies on the solvation of a protein.

Investigation of installation effects of single-engine convergent-divergent nozzles

NASA Technical Reports Server (NTRS)

Burley, J. R., II; Berrier, B. L.

1982-01-01

An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine installation effects on single-engine convergent-divergent nozzles applicable to reduced-power supersonic cruise aircraft. Tests were conducted at Mach numbers from 0.50 to 1.20, at angles of attack from -3 degrees to 9 degrees, and at nozzle pressure ratios from 1.0 (jet off) to 8.0. The effects of empennage arrangement, nozzle length, a cusp fairing, and afterbody closure on total aft-end drag coefficient and component drag coefficients were investigated. Basic lift- and drag-coefficient data and external static-pressure distributions on the nozzle and afterbody are presented and discussed.

Static properties of hydrostatic thrust gas bearings with curved surfaces.

NASA Technical Reports Server (NTRS)

Rehsteiner, F. H.; Cannon, R. H., Jr.

1971-01-01

The classical treatment of circular, hydrostatic, orifice-regulated thrust gas bearings, in which perfectly plane bearing plates are assumed, is extended to include axisymmetric, but otherwise arbitrary, plate profiles. Plate curvature has a strong influence on bearing load capability, static stiffness, tilting stiffness, and side force per unit misalignment angle. By a suitable combination of gas inlet impedance and concave plate profile, the static stiffness can be made almost constant over a wide load range, and to remain positive at the closure load. Extensive measurements performed with convex and concave plates agree with theory to within the experimental error throughout and demonstrate the practical feasibility of using curved plates.

On the folding phenomenon of comet tail rays

NASA Astrophysics Data System (ADS)

Ershkovich, A. I.

1982-01-01

It is shown that the folding phenomenon of the comet tail rays is compatible with the Ferraro isorotation law if the comet tail magnetic field has no azimuthal component, that is, Bphi (the polar angle) equals zero. Considering electric drift due to convectional electric fields, a formula is obtained for the angular rate of a ray closure which reduces to that of Ness and Donn (1966) if the velocity profile across the tail is linear. The magnetic field B of approximately 20-40 gammas in the coma and less than about 10 gammas in the distant tail is estimated under typical solar wind conditions at 1 AU.

Double hump sign in indentation gonioscopy is correlated with presence of plateau iris configuration regardless of patent iridotomy.

PubMed

Kiuchi, Yoshiaki; Kanamoto, Takashi; Nakamura, Takao

2009-02-01

A plateau iris is one of the clinical forms of angle closure glaucoma. In patients with a patent iridotomy, the double hump sign detected during indentation gonioscopy has been reported to indicate the existence of a plateau iris configuration. The purpose of this study was to determine whether the double hump sign is correlated with the presence of the plateau iris syndrome regardless of the patency of the iridotomy. Five women and 3 men without a patent iridotomy presented with narrow angles on gonioscopy and a double hump sign on indentation gonioscopy. Ultrasound biomicroscopy (UBM) imaging was performed to determine the etiology of the narrow angle and double hump sign, and to determine the appropriate treatment to prevent the progression of visual field damage. Ten patients with narrow angles and without a double hump sign were also examined by UBM to serve as a control group. All 8 patients who showed double hump sign had a short iris root, which was inserted anterior to the ciliary face, a typical anatomic appearance of a plateau iris. On the other hand, only 1 eye of 10 eyes in control group appeared to have a plateau iris. A double hump sign observed on indentation gonioscopy is strongly correlated with the presence of a plateau iris, and therefore a useful indicator of a plateau iris configuration regardless of the patency of a laser iridotomy. Thus, a plateau iris configuration can be detected without using a UBM in many cases.

Contact lens assisted imaging with integrated flexible handheld probe for glaucoma diagnosis

NASA Astrophysics Data System (ADS)

Hong, Xun Jie Jeesmond; V. K., Shinoj; Murukeshan, V. M.; Baskaran, M.; Aung, Tin

2017-06-01

Angle closure glaucoma accounts for majority of the bilateral blindness in Asian countries such as Singapore, China, and India. Abnormalities in the optic nerve and aqueous outflow system are the most indicative clinical hallmarks for glaucoma of this clinical subtype. Traditional photographic imaging techniques to assess the drainage angle are contact based, and may expose patients to risk of corneal abrasion and infections. In addition, these procedures require the use of viscous ophthalmic gels as coupling medium to overcome the phenomenon of total internal reflection at the tear-air interface. In this paper, we propose an integrated flexible handheld probe consisting of a micro color CCD video camera and white light LEDs. The handheld probe is able to capture images of the fundus and opposite iridocorneal angle when placed at the central cornea or limbus respectively. Here, we propose the use of hydrogel contact lens as an index matching medium and better protective barrier, as an alternative to conventional ophthalmic gels. The proposed imaging system and methodology has been successfully tested on porcine eye samples, ex vivo. With its high repeatability, reproducibility, and a good safety profile, it is believed that the proposed imaging system and methodology will complement existing imaging modalities in the diagnosis and management of glaucoma.

A potential carrier based on liquid crystal nanoparticles for ophthalmic delivery of pilocarpine nitrate.

PubMed

Li, Jing; Wu, Lin; Wu, Weijun; Wang, Baoyan; Wang, Zhongyuan; Xin, Hongliang; Xu, Qunwei

2013-10-15

Poor corneal penetration and short preocular retention of a clinical hydrophilic drug, pilocarpine nitrate (PN), for the treatment of open-angle glaucoma and acute angle-closure glaucoma, limit its ocular application. The purpose of this study was to investigate the potential of liquid crystal nanoparticles (LCNPs) for ocular delivery of PN. LCNPs were developed by a top-down method using glyceryl monoolein (GMO) and water in the presence of stabilizer Poloxamer 407. They were characterized by transmission electron microscopy (TEM) and small angle X-ray diffraction (SAXS). The size of LCNP is 202.28±19.32 nm and the encapsulation efficiency reached 61.03%. The in vitro release profiles indicated that PN could keep sustained release from PN-loaded LCNPs for 8h. An ex vivo corneal permeation study revealed that the apparent permeability coefficient of PN-loaded LCNPs was 2.05-fold higher than that of commercial eye drops. In addition, the topical administration test showed that PN-loaded LCNPs had a prolonged effect on decreasing intraocular pressure (IOP) of rabbits compared with commercial drug and physiological saline. In conclusion, LCNPs had been demonstrated to be potential for controlled-release ocular drug delivery. Copyright © 2013 Elsevier B.V. All rights reserved.

Glottis effects on the cough clearance process simulated with a CFD dynamic mesh and Eulerian wall film model.

PubMed

Paz, Concepción; Suárez, Eduardo; Parga, Oscar; Vence, Jesús

2017-09-01

In this study, we have reproduced the cough clearance process with an Eulerian wall film model. The simulated domain is based on realistic geometry from the literature, which has been improved by adding the glottis and epiglottis. The vocal fold movement has been included due to the dynamic mesh method, considering different abduction and adduction angles and velocities. The proposed methodology captures the deformation of the flexible tissue, considers non-Newtonian properties for the mucus, and enables us to reproduce a single cough or a cough epoch. The cough efficiency (CE) has been used to quantify the overall performance of the cough, considering many different boundary conditions, for the analysis of the glottis effect. It was observed that a viscous shear force is the main mechanism in the cough clearance process, while the glottis closure time and the epiglottis position do not have a significant effect on the CE. The cough assistance devices improve the CE, and the enhancement rate grows logarithmically with the operating pressure. The cough can achieve an effective mucus clearance process, even with a fixed glottis. Nevertheless, the glottis closure substantially improves the CE results.

Effect of spinal anaesthesia on the lower urinary tract in continent women.

PubMed

Haeusler, G; Sam, C; Chiari, A; Tempfer, C; Hanzal, E; Koelbl, H

1998-01-01

To evaluate the effect of spinal anaesthesia on the bladder neck position and the urethral closure function in the resting state and during clinical stress test in healthy, continent women. Controlled clinical trial. Department of Gynaecology and Obstetrics, Vienna University Medical School. Fourteen continent women, of which seven were nulliparous and seven parous, underwent minor gynaecological procedures under spinal anaesthesia. Urodynamics and ultrasound investigations were performed before and during spinal anaesthesia. Changes in the bladder neck position and the urethral closure function before and during spinal anaesthesia. Bladder neck position was found to be lower and more posterior during spinal anaesthesia as compared with pre-operative assessment. The posterior urethrovesical angle increased significantly both at rest and during maximum straining. We observed a significant increase in bladder compliance, and all parameters of the urethral pressure profile decreased significantly. While none of the nulliparous women had a positive clinical stress test during spinal anaesthesia, 4/7 parous women demonstrated leakage (Fisher's exact test, P = 0.003). Blockage of nerve supply to the pelvic floor muscles in continent women is associated with a significant loss of support of the bladder neck region confirming the theory of an active mechanism of muscular elements providing continence.

Response of Velocity Anisotropy of Shale Under Isotropic and Anisotropic Stress Fields

NASA Astrophysics Data System (ADS)

Li, Xiaying; Lei, Xinglin; Li, Qi

2018-03-01

We investigated the responses of P-wave velocity and associated anisotropy in terms of Thomsen's parameters to isotropic and anisotropic stress fields on Longmaxi shales cored along different directions. An array of piezoelectric ceramic transducers allows us to measure P-wave velocities along numerous different propagation directions. Anisotropic parameters, including the P-wave velocity α along a symmetry axis, Thomsen's parameters ɛ and δ, and the orientation of the symmetry axis, could then be extracted by fitting Thomsen's weak anisotropy model to the experimental data. The results indicate that Longmaxi shale displays weakly intrinsic velocity anisotropy with Thomsen's parameters ɛ and δ being approximately 0.05 and 0.15, respectively. The isotropic stress field has only a slight effect on velocity and associated anisotropy in terms of Thomsen's parameters. In contrast, both the magnitude and orientation of the anisotropic stress field with respect to the shale fabric are important in controlling the evolution of velocity and associated anisotropy in a changing stress field. For shale with bedding-parallel loading, velocity anisotropy is enhanced because velocities with smaller angles relative to the maximum stress increase significantly during the entire loading process, whereas those with larger angles increase slightly before the yield stress and afterwards decrease with the increasing differential stress. For shale with bedding-normal loading, anisotropy reversal is observed, and the anisotropy is progressively modified by the applied differential stress. Before reaching the yield stress, velocities with smaller angles relative to the maximum stress increase more significantly and even exceed the level of those with larger angles. After reaching the yield stress, velocities with larger angles decrease more significantly. Microstructural features such as the closure and generation of microcracks can explain the modification of the velocity anisotropy due to the applied stress anisotropy.

Cyclic coordinate descent: A robotics algorithm for protein loop closure.

PubMed

Canutescu, Adrian A; Dunbrack, Roland L

2003-05-01

In protein structure prediction, it is often the case that a protein segment must be adjusted to connect two fixed segments. This occurs during loop structure prediction in homology modeling as well as in ab initio structure prediction. Several algorithms for this purpose are based on the inverse Jacobian of the distance constraints with respect to dihedral angle degrees of freedom. These algorithms are sometimes unstable and fail to converge. We present an algorithm developed originally for inverse kinematics applications in robotics. In robotics, an end effector in the form of a robot hand must reach for an object in space by altering adjustable joint angles and arm lengths. In loop prediction, dihedral angles must be adjusted to move the C-terminal residue of a segment to superimpose on a fixed anchor residue in the protein structure. The algorithm, referred to as cyclic coordinate descent or CCD, involves adjusting one dihedral angle at a time to minimize the sum of the squared distances between three backbone atoms of the moving C-terminal anchor and the corresponding atoms in the fixed C-terminal anchor. The result is an equation in one variable for the proposed change in each dihedral. The algorithm proceeds iteratively through all of the adjustable dihedral angles from the N-terminal to the C-terminal end of the loop. CCD is suitable as a component of loop prediction methods that generate large numbers of trial structures. It succeeds in closing loops in a large test set 99.79% of the time, and fails occasionally only for short, highly extended loops. It is very fast, closing loops of length 8 in 0.037 sec on average.

RCRA, superfund and EPCRA hotline training module. Introduction to: Closure/post-closure (40 cfr parts 264/265, subpart g) updated July 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-07-01

The module explains the difference between closure and post-closure. It lists the types of facilities that are subject to closure/post-closures and defines the difference between partial and final closure. It specifies who submits a closure plan and when a closure plan must be submitted, lists the steps in the process, and states the time frame for submittal. It identifies when and how a closure must be amended. It explains the time frame for notification of closure and the deadlines for beginning and completing closure. It specifies which facilities need contingent post-closure plans and lists and the elements of post-closure andmore » cites the requirements. It specifies the conditions and timing for amending a post-closure plan and states who must certify closure/post-closure.« less

Pathophysiology of primary open-angle glaucoma from a neuroinflammatory and neurotoxicity perspective: a review of the literature.

PubMed

Evangelho, Karine; Mogilevskaya, Maria; Losada-Barragan, Monica; Vargas-Sanchez, Jeinny Karina

2017-12-30

Glaucoma is the leading cause of blindness in humans, affecting 2% of the population. This disorder can be classified into various types including primary, secondary, glaucoma with angle closure and with open angle. The prevalence of distinct types of glaucoma differs for each particular region of the world. One of the most common types of this disease is primary open-angle glaucoma (POAG), which is a complex inherited disorder characterized by progressive retinal ganglion cell death, optic nerve head excavation and visual field loss. Nowadays, POAG is considered an optic neuropathy, while intraocular pressure is proposed to play a fundamental role in its pathophysiology and especially in optic disk damage. However, the exact mechanism of optic nerve head damage remains a topic of debate. This literature review aims to bring together the information on the pathophysiology of primary open-angle glaucoma, particularly focusing on neuroinflammatory mechanisms leading to the death of the retinal ganglion cell. A literature search was done on PubMed using key words including primary open-angle glaucoma, retinal ganglion cells, Müller cells, glutamate, glial cells, ischemia, hypoxia, exitotoxicity, neuroinflammation, axotomy and neurotrophic factors. The literature was reviewed to collect the information published about the pathophysiologic mechanisms of RGC death in the POAG, from a neuroinflammatory and neurotoxicity perspective. Proposed mechanisms for glaucomatous damage are a result of pressure in RGC followed by ischemia, hypoxia of the ONH, and consequently death due to glutamate-induced excitotoxicity, deprivation of energy and oxygen, increase in levels of inflammatory mediators and alteration of trophic factors flow. These events lead to blockage of anterograde and retrograde axonal transport with ensuing axotomy and eventually blindness. The damage to ganglion cells and eventually glaucomatous injury can occur via various mechanisms including baric trauma, ischemia and impact of metabolic toxins, which triggers an inflammatory process and secondary degeneration in the ONH.

Mixed-mode crack tip loading and crack deflection in 1D quasicrystals

NASA Astrophysics Data System (ADS)

Wang, Zhibin; Scheel, Johannes; Ricoeur, Andreas

2016-12-01

Quasicrystals (QC) are a new class of materials besides crystals and amorphous solids and have aroused much attention of researchers since they were discovered. This paper presents a generalized fracture theory including the J-integral and crack closure integrals, relations between J1, J2 and the stress intensity factors as well as the implementation of the near-tip stress and displacement solutions of 1D QC. Different crack deflection criteria, i.e. the J-integral and maximum circumferential stress criteria, are investigated for mixed-mode loading conditions accounting for phonon-phason coupling. One focus is on the influence of phason stress intensity factors on crack deflection angles.

Navier-Stokes solution of transonic cascade flows using nonperiodic C-type grids

NASA Technical Reports Server (NTRS)

Arnone, Andrea; Liou, Meng-Sing; Povinelli, Louis A.

1992-01-01

A new kind of C-type grid is proposed, this grid is non-periodic on the wake and allows minimum skewness for cascades with high turning and large camber. Reynolds-averaged Navier-Stokes equations are solved on this type of grid using a finite volume discretization and a full multigrid method which uses Runge-Kutta stepping as the driving scheme. The Baldwin-Lomax eddy-viscosity model is used for turbulence closure. A detailed numerical study is proposed for a highly loaded transonic blade. A grid independence analysis is presented in terms of pressure distribution, exit flow angles, and loss coefficient. Comparison with experiments clearly demonstrates the capability of the proposed procedure.

Behavior and influence of desiccation cracking in loess landfill covers

NASA Astrophysics Data System (ADS)

Wu, Tao; Lan, Ji-wu; Qiu, Qing-wen; He, Hai-jie; Li, He

2017-11-01

In the northwest region of China, loess was the main closure cover material of local landfills. Tests in a full-scale testing facility were conducted to investigate the behavior and influence of desiccation cracking in loess landfill covers. The desiccation cracks in the loess landfill cover intersected with T-shape, and the intersection angles were close to 90 degrees. The desiccation cracks formed as a result of drying, and would heal with the increase of moisture content of the loess. In addition, desiccation cracking in loess covers would promote the formation of preferential flow channels. As a consequence, the gas permeability of the loess cover was improved, and methane emissions increased obviously.

40 CFR 265.310 - Closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...

40 CFR 265.310 - Closure and post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...

40 CFR 265.310 - Closure and post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Closure and post-closure care. 265.310... DISPOSAL FACILITIES Landfills § 265.310 Closure and post-closure care. (a) At final closure of the landfill... subsoils present. (b) After final closure, the owner or operator must comply with all post-closure...

[Uveitic Secondary Glaucoma].

PubMed

Lommatzsch, Claudia; Heinz, Carsten

2018-05-01

An intraocular pressure increase with development of glaucomatous damage is a common complication of uveitis. The prevalence has a wide range depending on various factors such as the underlying uveitis type and the duration of the disease. Pathogenetically, a distinction must be made between a secondary angle closure component and the more frequently occurring open-angle glaucoma. In diagnostics, in addition to the clinical optic nerve head assessment, perimetry and tonometry, the use of imaging examination equipment, such as OCT and HRT, are recommended. In the context of uveitic glaucoma, it must be considered in the evaluation, because the glaucoma-typical changes are generally less pronounced or can be concealed by retinal swelling in comparison with other forms of glaucoma. Therapeutically, drug therapy in the form of eye drops continues to be a first-line recommendation, with the use of topical carbonic anhydrase inhibitors or beta-blockers primarily preferred, depending on the contraindications. An operative therapy follows after unsuccessful or inadequate conservative therapy: the adequate surgical technique depends on the respective finding and includes actually techniques such as filtering procedures and glaucoma drainage devices. Georg Thieme Verlag KG Stuttgart · New York.

Afterbody Heating Characteristics of a Proposed Mars Sample Return Orbiter

NASA Technical Reports Server (NTRS)

Horvath, Thomas J.; Heiner, Nicholas C.; Olguin, Daniella M.; Cheatwood, F. McNeil; Gnoffo, Peter A.

2001-01-01

Aeroheating wind-tunnel tests were conducted on a 0.028 scale model of an orbiter concept considered for a possible Mars sample return mission. The primary experimental objectives were to characterize hypersonic near wake closure and determine if shear layer impingement would occur on the proposed orbiter afterbody at incidence angles necessary for a Martian aerocapture maneuver. Global heat transfer mappings, surface streamline patterns, and shock shapes were obtained in the NASA Langley 20-inch Mach 6 Air and CF4 Tunnels for post-normal shock Reynolds numbers (based on forebody diameter) ranging from 1,400 to 415,000, angles of attack ranging from -5 to 10 degrees at 0, 3, and 6 deg sideslip, and normal-shock density, ratios of 5 and 12. Laminar, transitional, and turbulent shear layer impingement on the cylindrical afterbody was inferred from the measurements and resulted in a localized heating maximum that ranged from 40 to 75% of the reference forebody stagnation point heating. Comparison of laminar heating prediction to experimental measurement along the orbiter afterbody highlight grid alignment challenges associated with numerical simulation of three-dimensional separated wake flows.

Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt.

PubMed

Hassan, P A; Fritz, Gerhard; Kaler, Eric W

2003-01-01

The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases.

Comparison of platelet function and viscoelastic test results between healthy dogs and dogs with naturally occurring chronic kidney disease.

PubMed

Dudley, Alicia; Byron, Julie K; Burkhard, Mary Jo; Warry, Emma; Guillaumin, Julien

2017-05-01

OBJECTIVE To compare platelet function and viscoelastic test results between healthy dogs and dogs with chronic kidney disease (CKD) to assess whether dogs with CKD have platelet dysfunction and altered blood coagulation. ANIMALS 10 healthy control dogs and 11 dogs with naturally occurring CKD. PROCEDURES Blood and urine were collected once from each dog for a CBC, serum biochemical analysis, urinalysis, and determination of the urine protein-to-creatinine ratio, prothrombin time, activated partial thromboplastin time, plasma fibrinogen concentration, and antithrombin activity. Closure time was determined by use of a platelet function analyzer and a collagen-ADP platelet agonist. Thromboelastography (TEG) variables (reaction time, clotting time, α angle, maximum amplitude, and global clot strength [G value]) were determined by use of recalcified nonactivated TEG. Platelet expression of glycoprotein Ib (GPIb; receptor for von Willebrand factor), integrin αIIbβ3 (αIIbβ3; receptor for fibrinogen), and P-selectin (marker for platelet activation) was assessed by flow cytometry. RESULTS Compared with healthy control dogs, the median closure time was prolonged, the median maximum amplitude and G value were increased, and the median clotting time was decreased for dogs with CKD. Platelet expression of both αIIbβ3 and P-selectin was also significantly increased for dogs with CKD, compared with that for control dogs. Platelet expression of GPIb, αIIbβ3, and P-selectin was not correlated with closure time or any TEG variable. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CKD frequently had evidence of platelet dysfunction and hypercoagulability that were not totally attributable to alterations in platelet surface expression of GPIb, αIIbβ3, and P-selectin.

Vitrectomy with internal limiting membrane peeling versus inverted internal limiting membrane flap technique for macular hole-induced retinal detachment: a systematic review of literature and meta-analysis.

PubMed

Yuan, Jing; Zhang, Ling-Lin; Lu, Yu-Jie; Han, Meng-Yao; Yu, Ai-Hua; Cai, Xiao-Jun

2017-11-28

To evaluate the effects on vitrectomy with internal limiting membrane (ILM) peeling versus vitrectomy with inverted internal limiting membrane flap technique for macular hole-induced retinal detachment (MHRD). Pubmed, Cochrane Library, and Embase were systematically searched for studies that compared ILM peeling with inverted ILM flap technique for macular hole-induced retinal detachment. The primary outcomes are the rate of retinal reattachment and the rate of macular hole closure 6 months later after initial surgery, the secondary outcome is the postoperative best-corrected visual acuity (BCVA) 6 months later after initial surgery. Four studies that included 98 eyes were selected. All the included studies were retrospective comparative studies. The preoperative best-corrected visual acuity was equal between ILM peeling and inverted ILM flap technique groups. It was indicated that the rate of retinal reattachment (odds ratio (OR) = 0.14, 95% confidence interval (CI):0.03 to 0.69; P = 0.02) and macular hole closure (OR = 0.06, 95% CI:0.02 to 0.19; P < 0.00001) after initial surgery was higher in the group of vitrectomy with inverted ILM flap technique than that in the group of vitrectomy with ILM peeling. However, there was no statistically significant difference in postoperative best-corrected visual acuity (mean difference (MD) 0.18 logarithm of the minimum angle of resolution; 95% CI -0.06 to 0.43 ; P = 0.14) between the two surgery groups. Compared with ILM peeling, vitrectomy with inverted ILM flap technique resulted significantly higher of the rate of retinal reattachment and macular hole closure, but seemed does not improve postoperative best-corrected visual acuity.

40 CFR 264.228 - Closure and post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...

40 CFR 264.228 - Closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...

40 CFR 264.228 - Closure and post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...

40 CFR 264.228 - Closure and post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...

40 CFR 264.228 - Closure and post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Closure and post-closure care. 264.228... Surface Impoundments § 264.228 Closure and post-closure care. (a) At closure, the owner or operator must... materials are left in place at final closure, the owner or operator must comply with all post-closure...

Morphologic Characteristics and Relating Factors to the Need of Technical Modification in Transcatheter Closure of Large Atrial Septal Defect (≥25 mm)

PubMed Central

Park, Su-Jin; Kim, Nam Kyun; Kim, Jung Ok; Yoo, Byung Won; Sul, Jun Hee

2010-01-01

Background and Objectives The rigid coupling between the delivery wire and the right atrial disk has been occasionally encountered during transcatheter closure of atrial septal defect (ASD). Therefore the device frequently makes a perpendicular angle, and the leading edge of left atrial disk slips through the defect and prolapses into right atrium (RA) before it is properly placed in the septum. The purpose of this study is to investigate relating factors to the need of technical modification in transcatheter closure of large ASD and to evaluate relevant morphologic characteristics of atrial septal rim in this situation. Subjects and Methods From July, 2003 to May, 2007, 312 patients underwent transcatheter occlusion of ASD with Amplatzer Septal Occluder® (ASO, AGA medical corporation, Golden Valley, MN, USA) at Yonsei Cardiovascular Center and among them 109 patients had large ASD (≥25 mm) and these patients were enrolled in our study. Patients were divided into two groups according to the deploying methods of the device (Group I: standard method, Group II: modified methods). Assessments of the defects and its surrounding rims were made by echocardiography. Results There were no differences between 2 groups in age, body weight and height except for balloon-stretched diameter (stop-flow technique) and device size. Group II patients with modified methods showed larger balloon-stretched diameter and device size than group I patients with standard method. The mean length of anterosuperior (AS) rim in group II was significantly shorter than group I (p<0.05). As the size of the device used in procedure increased, there was a trend towards increase in the need of modified methods. Conclusion This study shows that AS rim deficiency and the size of ASD may be the relating factors to the need of technical modification in transcatheter closure of ASD. Therefore, when the initial try with standard method is not successful in large ASD with deficient AS rim, we suggest that changing strategy of implantation may save time and efforts and possibly reduce the risk of complications associated with prolonged procedure. PMID:20421960

Age, Gender, Biometry, Refractive Error, and the Anterior Chamber Angle among Alaskan Eskimos

PubMed Central

Wojciechowski, Robert; Congdon, Nathan; Anninger, William; Broman, Aimee Teo

2011-01-01

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. PMID:12578783

Bidirectional reflectance of oceanic waters: A comparison of modeled and measured upward radiance fields

NASA Technical Reports Server (NTRS)

Morel, Andre; Voss, Kenneth J.; Gentili, Bernard

1995-01-01

The bidirectional reflectance of oceanic waters is conveniently described in a normalized way by forming the ratio of the upwelling irradiance E(sub u) to any upwelling radiance L(sub u)(theta prime, phi). This ratio, Q (theta prime, theta(sub 0), (phi(sub 0) - phi), where theta prime, phi are the nadir and azimuth angles for the upward radiance and theta(sub 0), phi(sub 0) are the zenith and azimuth angles of the Sun, has been determined from measurements at sea and computed via Monte Carlo simulations using the inherent optical properties measured in the field and appropriate boundary conditions (clear sky, no wind, varying Sun angle). Experimental ad computed Q values are in excellent agreement. This successful comparison confirms the importance of the bidirectional character of ocean reflectance, already pointed out from a purely numerical approach without field validation, and corroborates the extended range of the Q variations. The later point is of importance when interpreting the marine signals detected by an ocean color satellite-borne sensor. The validation is extended by considering the historical data for the radiance distributions in Lake Pend Oreille determined at various depths. The closure issue in ocean optics is examined by solving the direct problem of radiative transfer and through a model-data comparison in terms of radiance field.

40 CFR 265.228 - Closure and post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Closure and post-closure care. 265.228... DISPOSAL FACILITIES Surface Impoundments § 265.228 Closure and post-closure care. (a) At closure, the owner... impoundment and provide post-closure care for a landfill under subpart G and § 265.310, including the...

40 CFR 265.228 - Closure and post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Closure and post-closure care. 265.228... DISPOSAL FACILITIES Surface Impoundments § 265.228 Closure and post-closure care. (a) At closure, the owner... impoundment and provide post-closure care for a landfill under subpart G and § 265.310, including the...

INTERNAL LIMITING MEMBRANE PEELING VERSUS INVERTED FLAP TECHNIQUE FOR TREATMENT OF FULL-THICKNESS MACULAR HOLES: A COMPARATIVE STUDY IN A LARGE SERIES OF PATIENTS.

PubMed

Rizzo, Stanislao; Tartaro, Ruggero; Barca, Francesco; Caporossi, Tomaso; Bacherini, Daniela; Giansanti, Fabrizio

2017-12-08

The inverted flap (IF) technique has recently been introduced in macular hole (MH) surgery. The IF technique has shown an increase of the success rate in the case of large MHs and in MHs associated with high myopia. This study reports the anatomical and functional results in a large series of patients affected by MH treated using pars plana vitrectomy and gas tamponade combined with internal limiting membrane (ILM) peeling or IF. This is a retrospective, consecutive, nonrandomized comparative study of patients affected by idiopathic or myopic MH treated using small-gauge pars plana vitrectomy (25- or 23-gauge) between January 2011 and May 2016. The patients were divided into two groups according to the ILM removal technique (complete removal vs. IF). A subgroup analysis was performed according to the MH diameter (MH < 400 µm and MH ≥ 400 µm), axial length (AL < 26 mm and AL ≥ 26 mm), and the presence of chorioretinal atrophy in the macular area (present or absent). We included 620 eyes of 570 patients affected by an MH, 300 patients underwent pars plana vitrectomy and ILM peeling and 320 patients underwent pars plana vitrectomy and IF. Overall, 84.94% of the patients had complete anatomical success characterized by MH closure after the operation. In particular, among the patients who underwent only ILM peeling the closure rate was 78.75%; among the patients who underwent the IF technique, it was 91.93% (P = 0.001); and among the patients affected by full-thickness MH ≥400 µm, success was achieved in 95.6% of the cases in the IF group and in 78.6% in the ILM peeling group (P = 0.001); among the patients with an axial length ≥26 mm, success was achieved in 88.4% of the cases in the IF group and in 38.9% in the ILM peeling group (P = 0.001). Average preoperative best-corrected visual acuity was 0.77 (SD = 0.32) logarithm of the minimum angle of resolution (20/118 Snellen) in the peeling group and 0.74 (SD = 0.33) logarithm of the minimum angle of resolution (20/110 Snellen) in the IF group (P = 0.31). Mean postoperative best-corrected visual acuity was 0.52 (SD = 0.42) logarithm of the minimum angle of resolution (20/66 Snellen) in the peeling group and 0.43 (SD = 0.31) logarithm of the minimum angle of resolution (20/53 Snellen) in the IF group (P = 0.003). Vitrectomy associated with the inverted ILM flap technique seems to be effective surgery for idiopathic and myopic large MHs, improving both functional and anatomical outcomes.

Can early postoperative intraocular pressure predict success following mitomycin-C augmented trabeculectomy in primary angle-closure glaucoma.

PubMed

Rong, S S; Feng, M Y; Wang, N; Meng, H; Thomas, R; Fan, S; Wang, R; Wang, X; Tang, X; Liang, Y B

2013-03-01

To evaluate the association between early and late postoperative intraocular pressure (IOP) and determine if early postoperative IOP can predict the surgical outcome. A total of 165 consecutive patients with primary angle-closure glaucoma (PACG) undergoing primary mitomycin-C-augmented trabeculectomy underwent a comprehensive eye examination before surgery and were followed-up on days 1, 7, 14, and 30, and months 3, 6, 12, and 18. IOPs on days 1, 7, 14, and 30 were stratified into groups A (<10 mm Hg), B (≥10 and <15 mm Hg), C (≥15 and <20 mm Hg), and D (≥20 mm Hg). Differences between groups were analyzed using analysis of variance (ANOVA) and Fisher's exact test. Multivariable regression was used to exam the predictive ability of early IOP for final outcome. The mean age was 62.5±7.9 years and 41.21% (n=68) were males. Stratified by IOP on days 1, 7, 14, and 30, respectively, mean IOPs at month 18 were different among groups A, B, C, and D (ANOVA, P=0.047, P=0.033, P=0.008, and P<0.001, respectively). Once the IOPs were settled with interventions on day 7 a higher IOP level was associated with decreasing success rate under different outcome definitions, final IOP <15 mm Hg (Fisher's exact P=0.001) and <20 mm Hg (P=0.039) without medication. Multiple regression showed early IOP predicted final IOP independently from baseline variables. A cutoff value of 13.5 mm Hg on day 7 achieved an accuracy of 80.0 and 57.1% in predicting IOP<15 mm Hg without medication and failure after surgery, respectively. The IOP at 18 months following primary antifibrotic-augmented trabeculectomy in PACG patients is associated with and predicted by the postoperative IOPs at 1 month. Control of early IOP to 13.5 or less may provide better outcomes.

40 CFR 264.146 - Use of a mechanism for financial assurance of both closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... assurance of both closure and post-closure care. 264.146 Section 264.146 Protection of Environment... mechanism for financial assurance of both closure and post-closure care. An owner or operator may satisfy the requirements for financial assurance for both closure and post-closure care for one or more...

Tracking interface and common curve dynamics for two-fluid flow in porous media

DOE PAGES

Mcclure, James E.; Miller, Cass T.; Gray, W. G.; ...

2016-04-29

Pore-scale studies of multiphase flow in porous medium systems can be used to understand transport mechanisms and quantitatively determine closure relations that better incorporate microscale physics into macroscale models. Multiphase flow simulators constructed using the lattice Boltzmann method provide a means to conduct such studies, including both the equilibrium and dynamic aspects. Moving, storing, and analyzing the large state space presents a computational challenge when highly-resolved models are applied. We present an approach to simulate multiphase flow processes in which in-situ analysis is applied to track multiphase flow dynamics at high temporal resolution. We compute a comprehensive set of measuresmore » of the phase distributions and the system dynamics, which can be used to aid fundamental understanding and inform closure relations for macroscale models. The measures computed include microscale point representations and macroscale averages of fluid saturations, the pressure and velocity of the fluid phases, interfacial areas, interfacial curvatures, interface and common curve velocities, interfacial orientation tensors, phase velocities and the contact angle between the fluid-fluid interface and the solid surface. Test cases are studied to validate the approach and illustrate how measures of system state can be obtained and used to inform macroscopic theory.« less

Layout Slam with Model Based Loop Closure for 3d Indoor Corridor Reconstruction

NASA Astrophysics Data System (ADS)

Baligh Jahromi, A.; Sohn, G.; Jung, J.; Shahbazi, M.; Kang, J.

2018-05-01

In this paper, we extend a recently proposed visual Simultaneous Localization and Mapping (SLAM) techniques, known as Layout SLAM, to make it robust against error accumulations, abrupt changes of camera orientation and miss-association of newly visited parts of the scene to the previously visited landmarks. To do so, we present a novel technique of loop closing based on layout model matching; i.e., both model information (topology and geometry of reconstructed models) and image information (photometric features) are used to address a loop-closure detection. The advantages of using the layout-related information in the proposed loop-closing technique are twofold. First, it imposes a metric constraint on the global map consistency and, thus, adjusts the mapping scale drifts. Second, it can reduce matching ambiguity in the context of indoor corridors, where the scene is homogenously textured and extracting sufficient amount of distinguishable point features is a challenging task. To test the impact of the proposed technique on the performance of Layout SLAM, we have performed the experiments on wide-angle videos captured by a handheld camera. This dataset was collected from the indoor corridors of a building at York University. The obtained results demonstrate that the proposed method successfully detects the instances of loops while producing very limited trajectory errors.

40 CFR 265.146 - Use of a mechanism for financial assurance of both closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... assurance of both closure and post-closure care. 265.146 Section 265.146 Protection of Environment... Use of a mechanism for financial assurance of both closure and post-closure care. An owner or operator may satisfy the requirements for financial assurance for both closure and post-closure care for one or...

Gonioscopy in adult Chinese: the Liwan Eye Study.

PubMed

He, Mingguang; Foster, Paul J; Ge, Jian; Huang, Wenyong; Wang, Dandan; Friedman, David S; Khaw, Peng T

2006-11-01

To assess gonioscopic characteristics of the drainage angle in adult Chinese in an urban area of southern China. Clustered random sampling was used to select adults aged 50 years and older in Liwan District, Guangzhou. Gonioscopy was performed on all the subjects. The geometric angle width was graded in the superior and inferior quadrants, according to the Spaeth system. In addition, apparent and true iris insertion was classified in four quadrants with static and dynamic gonioscopy. The peripheral iris profile was described as steep, regular, concave, and plateau. Data are presented for all phakic right eyes. Secondary or iatrogenic cases were excluded in the analysis of peripheral anterior synechiae (PAS). Among 1405 participants in the study, data from 1330 (95%) right eyes were available for analysis. Iridotrabecular angles (ITA) < or =20 degrees were present in 36.9% (95% CI: 34.3%-40.0%) of eyes superiorly and in 27.9% (95% CI: 25.5%-30.4%) inferiorly. Narrower ITAs were more common in the older people (sex-adjusted odds ratio [OR] = 1.1 per year of life; P < 0.001) and the women (age-adjusted OR = 2.5, P < 0.001). Apparent iris insertion of grade A or B (with pigmented trabecular meshwork not visible) by quadrant was observed in 27.2% superiorly, 12.0% nasally, 7.7% inferiorly, and 14.2% temporally. Narrow angles (in which pigmented trabecular meshwork was not visible in three or more quadrants) were identified in 11.0% (95% CI: 9.3%-12.7%) of right eyes. Overall, 33.3% of eyes had a steep iris profile, 54.2% were normal, 2.7% were concave, and 10.1% were graded plateau. PAS were seen in 30 of 146 (20.5%) eyes with narrow angles and in 7 (0.6%) of 1184 eyes with angles that did not meet criteria for narrow angles. PAS were more likely with narrower angles, with 0%, 0.3%, and 1.9% of eyes with a mean ITA of 40 degrees, 30 degrees, and 20 degrees, respectively, having PAS as opposed to 12.6% and 27.5% for those with ITA 10 degrees and 0 degrees , respectively. Ten percent of this population of southern Chinese persons 50 years of age and older had narrow angles. PAS were present in one fifth of these people. From these cross-sectional data, it is unclear which of these individuals are at highest risk of the development of primary angle-closure (PAC) glaucoma. Longitudinal studies are necessary to determine appropriate strategies for preventing this potentially blinding outcome.

Anterior capsule tear after laser iridotomy complicating phacoemulsification

PubMed Central

Vivien Cherng Hui, Yip; Sanjay, Srinivasan; Benjamin Chong-Ming, Chang

2011-01-01

A 70-year-old Indian lady had a history of bilateral laser peripheral iridotomy (LPI) for primary angle closure. Subsequently she developed cataract in both the eyes. Right eye cataract surgery was complicated by an anterior capsule rupture, which was discovered intra-operatively at the site of the LPI. Trypan blue was used to stain the anterior capsule to delineate the anterior capsule defect. An attempt at continuous curvilinear capsulorhexis was unsuccessful, and the anterior capsulotomy was completed with scissors. To the best of our knowledge the surgical management of cataract in the presence of anterior capsule rupture as a result of LPI has not been reported. Awareness of this potential complication of LPI will aid in planning for successful phacoemulsification cataract surgery. PMID:23960943

Evaluation of AirMSPI photopolarimetric retrievals of smoke properties with in-situ observations collected during the ImPACT-PM field campaign

NASA Astrophysics Data System (ADS)

Kalashnikova, O. V.; Garay, M. J.; Xu, F.; Seidel, F.; Diner, D. J.; Seinfeld, J.; Bates, K. H.; Kong, W.; Kenseth, C.; Cappa, C. D.

2017-12-01

We introduce and evaluate an approach for obtaining closure between in situ and polarimetric remote sensing observations of smoke properties obtained during the collocated CIRPAS Twin Otter and ER-2 aircraft measurements of the Lebec fire event on July 8, 2016. We investigate the utility of multi-angle, spectropolarimetric remote sensing imagery to evaluate the relative contribution of organics, non-organic and black carbon particles to smoke particulate composition. The remote sensing data were collected during the Imaging Polarimetric and Characterization of Tropospheric Particular Matter (ImPACT-PM) field campaign by the Airborne Multiangle SpectroPolarimetric Imager (AirMSPI), which flew on NASA's high-altitude ER-2 aircraft. The ImPACT-PM field campaign was a joint JPL/Caltech effort to combine measurements from the Terra Multi-angle Imaging SpectroRadiometer (MISR), AirMSPI, in situ airborne measurements, and a chemical transport model to validate remote sensing retrievals of different types of airborne particulate matter with a particular emphasis on carbonaceous aerosols. The in-situ aerosol data were collected with a suite of Caltech instruments on board the CIRPAS Twin Otter aircraft and included the Aerosol Mass Spectrometer (AMS), the Differential Mobility Analyzer (DMA), and the Single Particle Soot Photometer (SP-2). The CIRPAS Twin Otter aircraft was also equipped with the Particle Soot Absorption Photometer (PSAP), nephelometer, a particle counter, and meteorological sensors. We found that the multi-angle polarimetric observations are capable of fire particulate emission monitoring by particle type as inferred from the in-situ airborne measurements. Modeling of retrieval sensitivities show that the characterization of black carbon is the most challenging. The work aims at evaluating multi-angle, spectropolarimetric capabilities for particulate matter characterization in support of the Multi-Angle Imager for Aerosols (MAIA) satellite investigation, which is currently in development under NASA's third Earth Venture Instrument Program.

Management of hidradenitis suppurativa wounds with an internal vacuum-assisted closure device.

PubMed

Chen, Y Erin; Gerstle, Theodore; Verma, Kapil; Treiser, Matthew D; Kimball, Alexandra B; Orgill, Dennis P

2014-03-01

Hidradenitis suppurativa is a chronic, debilitating disease that is difficult to treat. Once medical management fails, wide local excision offers the best chance for cure. However, the resultant wound often proves too large or contaminated for immediate closure. The authors performed a retrospective chart review of hidradenitis cases managed surgically between 2005 and 2010. Data collected included patient characteristics, management method, and outcomes. Approximately half of the patients received internal vacuum-assisted closure therapy using the vacuum-assisted closure system and delayed closure and half of the patients received immediate primary closure at the time of their excision. Delayed closure consisted of closing the majority of the wound in a linear fashion following internal vacuum-assisted closure while accepting healing by means of secondary intention for small wound areas. Patients managed with internal vacuum-assisted closure had wounds on average four times larger in area than patients managed without internal vacuum-assisted closure. In both groups, all wounds were eventually closed primarily. Healing times averaged 2.2 months with internal vacuum-assisted closure and 2.7 months without. At an average follow-up time of 2.3 months, all patients with internal vacuum-assisted closure had no recurrence of their local disease. Severe hidradenitis presents a treatment challenge, as surgical excisions are often complicated by difficult closures and unsatisfactory recurrence rates. This study demonstrates that wide local excision with reasonable outcomes can be achieved using accelerated delayed primary closure. This method uses internal vacuum-assisted closure as a bridge between excision and delayed primary closure, facilitating closure without recurrence in large, heavily contaminated wounds. Therapeutic, III.

Effects of Catch-and-Release Angling on Salmonids at Elevated Water Temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boyd, James W.; Guy, Christopher S.; Horton, Travis

2010-08-01

Few studies have assessed catch and release mortality of salmonids at water temperatures ≥23°C, despite predictions of warming stream temperatures due to climate change. In addition, the effects of diel temperature fluctuations on salmonid mortality have largely been ignored in catch and release angling studies. The primary objective of this study was to measure catch and release mortality of rainbow trout Oncorhynchus mykiss, brown trout Salmo trutta, and mountain whitefish Prosopium williamsoni in three water temperature treatments; when daily maximum water temperatures were cool (<20°C), warm (20 to 22.9°C), and hot ( 23°C). A secondary objective was to assess catchmore » and release mortality of salmonids angled in morning and evening within water-temperature treatments. These objectives were related to Montana Fish, Wildlife and Parks’ Drought Fishing Closure Policy (DFCP). Angling (fly-fishing only) occurred in the Gallatin and Smith rivers. All angled fish were confined to in-stream holding cages and monitored for mortality for 72 h. Mortality of rainbow trout peaked at 16% in the Gallatin River and 9% in the Smith River during the hot treatment. Mortality of brown trout was less than 5% in all water-temperature treatments in both rivers. Mountain whitefish mortality peaked at 28% in the hot treatment in the Smith River. No mortality for any species occurred in either river when daily maximum water temperatures were <20°C. Mortality of rainbow trout peaked at 16% in the evening hot treatment in the Smith River. Mortality of brown trout and mountain whitefish was not related to time of day. The catch and release mortality values presented here likely represent fishing mortality given that most anglers in southwest Montana practice catch and release angling. The mortality values we observed were lower than predicted (< 30%), given reports in the literature. The difference is likely related to the in situ nature of the study and periods of cooler water temperatures between peaks facilitating recovery from thermal stress.« less

Natural orifice transluminal endoscopic surgery gastrotomy closure with an over-the-endoscope clip: a randomized, controlled porcine study (with videos).

PubMed

von Renteln, Daniel; Schmidt, Arthur; Vassiliou, Melina C; Gieselmann, Maria; Caca, Karel

2009-10-01

Secure endoscopic closure of transgastric natural orifice transluminal endoscopic surgery (NOTES) access is of paramount importance. The over-the-scope clip (OTSC) system has previously been shown to be effective for NOTES gastrotomy closure. To compare OTSC gastrotomy closure with surgical closure. Randomized, controlled animal study. Animal facility laboratory. Thirty-six female domestic pigs. Gastrotomies were created by using a needle-knife and an 18-mm balloon. The animals were subsequently randomized to either open surgical repair with interrupted sutures or endoscopic repair with 12-mm OTSCs. In addition, pressurized leak tests were performed in ex vivo specimens of 18-mm scalpel incisions closed with suture (n = 14) and of intact stomachs (n = 10). The mean time for endoscopic closure was 9.8 minutes (range 3-22, SD 5.5). No complications occurred during either type of gastrotomy closure. At necropsy, examination of all OTSC and surgical closures demonstrated complete sealing of gastrotomy sites without evidence of injury to adjacent organs. Pressurized leak tests showed a mean burst pressure of 83 mm Hg (range 30-140, SD 27) for OTSC closures and 67 mm Hg (range 30-130, SD 27.7) for surgical sutures. Ex vivo hand-sewn sutures of 18-mm gastrotomies (n = 14) exhibited a mean burst pressure of 65 mm Hg (range 20-140, SD 31) and intact ex vivo stomachs (n = 10) had a mean burst pressure of 126 mm Hg (range 90-170, SD 28). The burst pressure of ex vivo intact stomachs was significantly higher compared with OTSC closures (P < .01), in vivo surgical closures (P < .01), and ex vivo hand-sewn closures (P < .01). There was a trend toward higher burst pressures in the OTSC closures compared with surgical closures (P = .063) and ex vivo hand-sewn closures (P = .094). In vivo surgical closures demonstrated similar burst pressures compared with ex vivo hand-sewn closures (P = .848). Nonsurvival setting. Endoscopic closure by using the OTSC system is comparable to surgical closure in a nonsurvival porcine model. This technique is easy to perform and is suitable for NOTES gastrotomy closure.

Evaluation of the Momentum Closure Schemes in MPAS-Ocean

NASA Astrophysics Data System (ADS)

Zhao, Shimei; Liu, Yudi; Liu, Wei

2018-04-01

In order to compare and evaluate the performances of the Laplacian viscosity closure, the biharmonic viscosity closure, and the Leith closure momentum schemes in the MPAS-Ocean model, a variety of physical quantities, such as the relative reference potential energy (RPE) change, the RPE time change rate (RPETCR), the grid Reynolds number, the root mean square (RMS) of kinetic energy, and the spectra of kinetic energy and enstrophy, are calculated on the basis of results of a 3D baroclinic periodic channel. Results indicate that: 1) The RPETCR demonstrates a saturation phenomenon in baroclinic eddy tests. The critical grid Reynolds number corresponding to RPETCR saturation differs between the three closures: the largest value is in the biharmonic viscosity closure, followed by that in the Laplacian viscosity closure, and that in the Leith closure is the smallest. 2) All three closures can effectively suppress spurious dianeutral mixing by reducing the grid Reynolds number under sub-saturation conditions of the RPETCR, but they can also damage certain physical processes. Generally, the damage to the rotation process is greater than that to the advection process. 3) The dissipation in the biharmonic viscosity closure is strongly dependent on scales. Most dissipation concentrates on small scales, and the energy of small-scale eddies is often transferred to large-scale kinetic energy. The viscous dissipation in the Laplacian viscosity closure is the strongest on various scales, followed by that in the Leith closure. Note that part of the small-scale kinetic energy is also transferred to large-scale kinetic energy in the Leith closure. 4) The characteristic length scale L and the dimensionless parameter D in the Leith closure are inherently coupled. The RPETCR is inversely proportional to the product of D and L. When the product of D and L is constant, both the simulated RPETCR and the inhibition of spurious dianeutral mixing are the same in all tests using the Leith closure. The dissipative scale in the Leith closure depends on the parameter L, and the dissipative intensity depends on the parameter D. 5) Although optimal results may not be achieved by using the optimal parameters obtained from the 2D barotropic model in the 3D baroclinic simulation, the total energies are dissipative in all three closures. Dissipation is the strongest in the biharmonic viscosity closure, followed by that in the Leith closure, and that in the Laplacian viscosity closure is the weakest. Mesoscale eddies develop the fastest in the biharmonic viscosity closure after the baroclinic adjustment process finishes, and the kinetic energy reaches its maximum, which is attributed to the smallest dissipation of enstrophy in the biharmonic viscosity closure. Mesoscale eddies develop the slowest, and the kinetic energy peak value is the smallest in the Laplacian viscosity closure. Results in the Leith closure are between that in the biharmonic viscosity closure and the Laplacian viscosity closure.

Penetrating head injury from angle grinder: A cautionary tale.

PubMed

Senthilkumaran, S; Balamurgan, N; Arthanari, K; Thirumalaikolundusubramanian, P

2010-01-01

Penetrating cranial injury is a potentially life-threatening condition. Injuries resulting from the use of angle grinders are numerous and cause high-velocity penetrating cranial injuries. We present a series of two penetrating head injuries associated with improper use of angle grinder, which resulted in shattering of disc into high velocity missiles with reference to management and prevention. One of those hit on the forehead of the operator and the other on the occipital region of the co-worker at a distance of five meters. The pathophysiological consequence of penetrating head injuries depends on the kinetic energy and trajectory of the object. In the nearby healthcare center the impacted broken disc was removed without realising the consequences and the wound was packed. As the conscious level declined in both, they were referred. CT brain revealed fracture in skull and changes in the brain in both. Expeditious removal of the penetrating foreign body and focal debridement of the scalp, skull, dura, and involved parenchyma and Watertight dural closure were carried out. The most important thing is not to remove the impacted foreign body at the site of accident. Craniectomy around the foreign body, debridement and removal of foreign body without zigzag motion are needed. Removal should be done following original direction of projectile injury. The neurological sequelae following the non missile penetrating head injuries are determined by the severity and location of initial injury as well as the rapidity of the exploration and fastidious debridement.

Numerical calculation of the neoclassical electron distribution function in an axisymmetric torus

NASA Astrophysics Data System (ADS)

Lyons, B. C.; Jardin, S. C.; Ramos, J. J.

2011-10-01

We solve for a stationary, axisymmetric electron distribution function (fe) in a torus using a drift-kinetic equation (DKE) with complete Landau collision operator. All terms are kept to gyroradius and collisionality orders relevant to high- temperature tokamaks (i.e., the neoclassical banana regime for electrons). A solubility condition on the DKE determines the non-Maxwellian pieces of fe (called fNMe) to all relevant orders. We work in a 4D phase space (ψ , θ , v , λ) , where ψ defines a flux surface, θ is the poloidal angle, v is the total velocity, and λ is the pitch angle parameter. We expand fNMe in finite elements in both v and λ. The Rosenbluth potentials, Φ and Ψ, which define the collision operator, are expanded in Legendre series in cos χ , where χ is the pitch angle, Fourier series in cos θ , and finite elements in v. At each ψ, we solve a block tridiagonal system for fNMe, Φ, and Ψ simultaneously, resulting in a neoclassical fe for the entire torus. Our goal is to demonstrate that such a formulation can be accurately and efficiently solved numerically. Results will be compared to other codes (e.g., NCLASS, NEO) and could be used as a kinetic closure for an MHD code (e.g., M3D-C1). Supported by the DOE SCGF and DOE Contract # DE-AC02-09CH11466. Based on analytic work by Ramos, PoP 17, 082502 (2010).

40 CFR 264.151 - Wording of the instruments.

Code of Federal Regulations, 2013 CFR

2013-07-01

... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...

40 CFR 264.151 - Wording of the instruments.

Code of Federal Regulations, 2012 CFR

2012-07-01

... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...

40 CFR 264.151 - Wording of the instruments.

Code of Federal Regulations, 2010 CFR

2010-07-01

... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... CFR parts 264 and 265. The current closure and/or post-closure cost estimate covered by the test are...

40 CFR 264.118 - Post-closure plan; amendment of plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...

40 CFR 264.118 - Post-closure plan; amendment of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...

40 CFR 264.118 - Post-closure plan; amendment of plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...

40 CFR 264.118 - Post-closure plan; amendment of plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...

40 CFR 264.118 - Post-closure plan; amendment of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... days after an unexpected event has occurred which has affected the post-closure plan. An owner or... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Post-closure plan; amendment of plan... FACILITIES Closure and Post-Closure § 264.118 Post-closure plan; amendment of plan. (a) Written Plan. The...

Detection of Glaucoma Using Image Processing Techniques: A Critique.

PubMed

Kumar, B Naveen; Chauhan, R P; Dahiya, Nidhi

2018-01-01

The primary objective of this article is to present a summary of different types of image processing methods employed for the detection of glaucoma, a serious eye disease. Glaucoma affects the optic nerve in which retinal ganglion cells become dead, and this leads to loss of vision. The principal cause is the increase in intraocular pressure, which occurs in open-angle and angle-closure glaucoma, the two major types affecting the optic nerve. In the early stages of glaucoma, no perceptible symptoms appear. As the disease progresses, vision starts to become hazy, leading to blindness. Therefore, early detection of glaucoma is needed for prevention. Manual analysis of ophthalmic images is fairly time-consuming and accuracy depends on the expertise of the professionals. Automatic analysis of retinal images is an important tool. Automation aids in the detection, diagnosis, and prevention of risks associated with the disease. Fundus images obtained from a fundus camera have been used for the analysis. Requisite pre-processing techniques have been applied to the image and, depending upon the technique, various classifiers have been used to detect glaucoma. The techniques mentioned in the present review have certain advantages and disadvantages. Based on this study, one can determine which technique provides an optimum result.

Expertise on glaucoma patients (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leydhecker, W.

1973-02-01

The difficuities encountered in cases of glaucoma where external factors are brought into relationship with the disease are discussed. The discussion is based on the author's own case collection. Glaucoma simplex seldom requires compensation e.g., when medical treatment had been impossible over several years. Acute angle glaucoma requires compensation when its occurrence can be brought into connection with an exceptionally emotional environmental situation. In chronic angle closure glaucoma an aggravation of the situation brings about an acute increase of I. O. P. or when treatment has been impossible. A glaucoma can occur decades after tears of the ciliary body aftermore » contusions. The diagnosis can be established only through comparative gonioscopy of the two eyes. Even complicated cases can be clarified through exact reconstruction of the course of disease and the findings supported by consultations with the ophthalmologists who treated the cases before. Examples of such cases are shown. Consensual changes of I. O. P. occurred oniy in 0.5% of cases. The question of conditions under which the assumption of a consenual glaucoma can be apparently assumed is discussed. A case of secondary pigmentary glaucoma through x rays is presented. (auth)« less

Ghost shrimps (Decapoda: Axiidea: Callianassidae) as producers of an Upper Miocene trace fossil association from sublittoral deposits of Lake Pannon (Vienna Basin, Slovakia)

PubMed Central

Hyžný, Matúš; Šimo, Vladimír; Starek, Dušan

2015-01-01

Numerous trace fossils are described from the Late Miocene sediments of the Bzenec Formation exposed at the Gbely section (the Vienna Basin, Slovakia). During deposition of the sediments the area was part of the large, long-lived brackish to freshwater Lake Pannon. Most of the trace fossils are attributed herein to Egbellichnus jordidegiberti igen et ispec. nov. and are interpreted as burrows produced by decapod crustaceans, specifically by a ghost shrimp of the family Callianassidae. This interpretation is based on two independent lines of evidence: environmental requirements of large bioturbators and the burrow morphology itself. The new ichnotaxon is distinguished from other related ichnotaxa by a combination of typically inclined (roughly at an angle of 45°) cylindrical burrows, absence of lining, and tunnels making loops or bends at approximately right angles. The burrow systems at Gbely document the survival of ghost shrimp long after the closure of all seaways and the origin of Lake Pannon. As today, no ghost shrimp are known from long-lived brackish lakes. Egbellichnus from Gbely is the only, although indirect, record of ghost shrimp from a brackish lake environment reported so far. PMID:26089575

Changes in small angle X-ray scattering parameters observed upon ligand binding to rabbit muscle pyruvate kinase are not correlated with allosteric transitions†

PubMed Central

Fenton, Aron W.; Williams, Rachel; Trewhella, Jill

2010-01-01

Protein fluorescence and small-angle X-ray scattering (SAXS) have been used to monitor effector affinity and conformational changes previously associated with allosteric regulation in rabbit muscle pyruvate kinase (M1-PYK). In the absence of substrate (phosphoenolpyruvate; PEP), SAXS-monitored conformational changes in M1-PYK elicited by the binding of phenylalanine (an allosteric inhibitor that reduces the affinity of M1-PYK for PEP) are similar to those observed upon binding of alanine or 2-aminobutyric acid. Under the current assay conditions, these small amino acids bind to the protein, but elicit a minimal change in the affinity of the protein for PEP. Therefore, if changes in scattering signatures represent cleft closure via domain rotation as previously interpreted, it can be concluded that these motions are not sufficient to elicit allosteric inhibition. Additionally, although PEP has similar affinities for the free enzyme and the M1-PYK/small-amino-acid complexes (i.e. the small amino acids have minimal allosteric effects), PEP binding elicits different changes in the SAXS signature of the free enzyme vs. the M1-PYK/small-amino-acid complexes. PMID:20712377

An inverse inviscid method for the design of quasi-three dimensional rotating turbomachinery cascades

NASA Technical Reports Server (NTRS)

Bonataki, E.; Chaviaropoulos, P.; Papailiou, K. D.

1991-01-01

A new inverse inviscid method suitable for the design of rotating blade sections lying on an arbitrary axisymmetric stream-surface with varying streamtube width is presented. The geometry of the axisymmetric stream-surface and the streamtube width variation with meridional distance, the number of blades, the inlet flow conditions, the rotational speed and the suction and pressure side velocity distributions as functions of the normalized arc-length are given. The flow is considered irrotational in the absolute frame of reference and compressible. The output of the computation is the blade section that satisfies the above data. The method solves the flow equations on a (phi 1, psi) potential function-streamfunction plane for the velocity modulus, W and the flow angle beta; the blade section shape can then be obtained as part of the physical plane geometry by integrating the flow angle distribution along streamlines. The (phi 1, psi) plane is defined so that the monotonic behavior of the potential function is guaranteed, even in cases with high peripheral velocities. The method is validated on a rotating turbine case and used to design new blades. To obtain a closed blade, a set of closure conditions were developed and referred.

[Emphasis on promotion of the adaptive technology is the sky point of improving of treatment and prevention level of glaucoma].

PubMed

Wang, Ning-li

2013-11-01

Promoting the control of primary angle-closure glaucoma (PACG) and primary open angle glaucoma (POAG) is most important prevention program of blindness in China. PACG has been incorporated into the prevention program of blindness in China based on the population-based screening studies. However, the clinical screening should be strengthened in POAG. The creation of a series of appropriate technologies suitable for glaucoma prevention and management has been achieved in China, especially for PACG. The technologies have been evaluated in the pilot areas and obtained very good results in China. It is recommended to develop new technology suitable for glaucoma management using the following workflow: research, development, and evaluation by large scale hospitals, and then clinical trial in the pilot areas. After a cost-benefit analysis is made, the new technology can be promoted and applied in clinical practice nationwide. We propose to gradually formed a strategical mode of "screening in township hospitals, intervention in county hospitals, and technical support and tackling in provincial hospitals" in order to improve the level of prevention and treatment of glaucoma and reduce the blindness incidence rate caused by glaucoma.

Pseudoexfoliation syndrome in Ethiopian glaucoma patients.

PubMed

Bedri, A; Alemu, B

1999-05-01

Pseudoexfoliation syndrome (PXS) has variable prevalence rates in the glaucoma population depending on geographic location and racial composition of the population studied. There is no data available on this subject in Ethiopia. To determine the prevalence of PXS among Ethiopian glaucoma clinic population. A prospective study. The Glaucoma Clinic of Menelik-II-Hospital, which is a tertiary eye care centre in Addis Ababa, Ethiopia. All new patients with glaucoma or ocular hypertension (ocular HPN) seen during the study period from 1st April to 30th September 1996 were included in the study. Our of the 432 new patients of glaucoma or ocular HPN seen during the study, 108 patients (25%) had PXS. The age of PXS cases ranged from 32 years to 86 years (mean 62.3 years). There were 80 males and 28 females. Of the PXS patients, 104 (96.3%) were cases of chronic open angle glaucoma, while angle closure glaucoma and ocular HPN were rare comprising only two patients (1.85%) each. The relatively high prevalence rate of PXS among Ethiopian glaucoma clinic population found in this study stresses the need for further community-based research in order to prevent blindness due to glaucoma associated with PXS.

Verification of continuum drift kinetic equation solvers in NIMROD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Held, E. D.; Ji, J.-Y.; Kruger, S. E.

Verification of continuum solutions to the electron and ion drift kinetic equations (DKEs) in NIMROD [C. R. Sovinec et al., J. Comp. Phys. 195, 355 (2004)] is demonstrated through comparison with several neoclassical transport codes, most notably NEO [E. A. Belli and J. Candy, Plasma Phys. Controlled Fusion 54, 015015 (2012)]. The DKE solutions use NIMROD's spatial representation, 2D finite-elements in the poloidal plane and a 1D Fourier expansion in toroidal angle. For 2D velocity space, a novel 1D expansion in finite elements is applied for the pitch angle dependence and a collocation grid is used for the normalized speedmore » coordinate. The full, linearized Coulomb collision operator is kept and shown to be important for obtaining quantitative results. Bootstrap currents, parallel ion flows, and radial particle and heat fluxes show quantitative agreement between NIMROD and NEO for a variety of tokamak equilibria. In addition, velocity space distribution function contours for ions and electrons show nearly identical detailed structure and agree quantitatively. A Θ-centered, implicit time discretization and a block-preconditioned, iterative linear algebra solver provide efficient electron and ion DKE solutions that ultimately will be used to obtain closures for NIMROD's evolving fluid model.« less

40 CFR 261.151 - Wording of the instruments.

Code of Federal Regulations, 2013 CFR

2013-07-01

... assurance for closure or post-closure care is demonstrated through the financial test specified in subpart H... parts 264 and 265. The current closure and/or post-closure cost estimates covered by such a test are... financial test specified in subpart H of 40 CFR parts 264 and 265. The current closure and/or post-closure...

50 CFR 660.360 - Recreational fishery-management measures.

Code of Federal Regulations, 2011 CFR

2011-10-01

... authorized for recreational fishing are hook-and-line and spear. Spears may be propelled by hand or by... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed...

50 CFR 660.360 - Recreational fishery-management measures.

Code of Federal Regulations, 2012 CFR

2012-10-01

... authorized for recreational fishing are hook-and-line and spear. Spears may be propelled by hand or by... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed... when the closure is in effect. The closure is not in effect at this time. This closure may be imposed...

Evaluation of Container Closure System Integrity for Frozen Storage Drug Products.

PubMed

Nieto, Alejandra; Roehl, Holger; Brown, Helen; Nikoloff, Jonas; Adler, Michael; Mahler, Hanns-Christian

2016-01-01

Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Shipment of frozen product could potentially be performed in the frozen state, yet possibly at different temperatures, for example, using dry ice (-80 °C). Container closure systems of drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Below their Tg, rubber stoppers are known to lose their elastic properties and become brittle, and thus potentially fail to maintain container closure integrity in the frozen state. Leaks during frozen temperature storage and transportation are likely to be transient, yet, can possibly risk container closure integrity and lead to microbial contamination. After thawing, the rubber stopper is supposed to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal physical container closure integrity) for direct assessment of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, different container closure systems were evaluated with regard to physical container closure integrity in the frozen state to assess the suitability of vial/stopper combinations and were compared to a gas headspace method. In summary, the thermal physical container closure integrity He leakage method was more sensitive in detecting physical container closure integrity impact than gas headspace and aided identification of an unsuitable container closure system. Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Container closure systems for drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Leaks during frozen temperature storage and transportation are likely to be transient, yet they can possibly risk container closure integrity and lead to microbial contamination and sterility breach. After thawing, the rubber stopper is expected to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal container closure integrity) for direct measurement of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, we found that the thermal container closure integrity He leakage method was more sensitive in detecting physical container closure integrity impact than gas headspace and aided identification of an unsuitable container closure system. © PDA, Inc. 2016.

Resource Conservation and Recovery Act closure report: Area 2 Bitcutter and Postshot Containment Shops Injection Wells, Correction Action Unit 90

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

This Closure Report provides documentation of the activities conducted during the Resource Conservation and Recovery Act (RCRA) closure of the Bitcutter and Postshot Containment Shops Injection Wells located in Area 2 of the Nevada Test Site (NTS), Oak Spring Quadrangle (USGS, 1986), Township 10 South, Range 53 East, Nye County, Nevada. This report discusses the Bitcutter Shop Inside Injection Well (CAU 90-A) closure-in-place and the Bitcutter Shop Outside Injection Well (CAU 90-B) and Postshot Containment Shop Injection Well (CAU 90-C) clean closures. This Closure Report provides background information about the unit, the results of the characterization activities and actions conductedmore » to determine the closure design. It also provides a discussion of the drainage analysis, preliminary closure activities, final closure activities, waste management activities, and the Post-Closure Care requirements.« less

Linearly exact parallel closures for slab geometry

NASA Astrophysics Data System (ADS)

Ji, Jeong-Young; Held, Eric D.; Jhang, Hogun

2013-08-01

Parallel closures are obtained by solving a linearized kinetic equation with a model collision operator using the Fourier transform method. The closures expressed in wave number space are exact for time-dependent linear problems to within the limits of the model collision operator. In the adiabatic, collisionless limit, an inverse Fourier transform is performed to obtain integral (nonlocal) parallel closures in real space; parallel heat flow and viscosity closures for density, temperature, and flow velocity equations replace Braginskii's parallel closure relations, and parallel flow velocity and heat flow closures for density and temperature equations replace Spitzer's parallel transport relations. It is verified that the closures reproduce the exact linear response function of Hammett and Perkins [Phys. Rev. Lett. 64, 3019 (1990)] for Landau damping given a temperature gradient. In contrast to their approximate closures where the vanishing viscosity coefficient numerically gives an exact response, our closures relate the heat flow and nonvanishing viscosity to temperature and flow velocity (gradients).

Observations on early and delayed colostomy closure.

PubMed

Tade, A O; Salami, B A; Ayoade, B A

2011-06-01

Traditional treatment of a variety of colorectal pathologies had included a diverting colostomy that was closed eight or more weeks later during a readmission. The aim of this retrospective study was to determine the outcomes of early colostomy closure and delayed colostomy closure in patients with temporary colostomies following traumatic and non-traumatic colorectal pathologies. In this study early colostomy closure was the closure of a colostomy within three weeks of its construction, while delayed colostomy closure referred to closure after 3 weeks. Complete records of the 37 adult patients who had temporary colostomy constructed and closed between Jan. 1997 December 2003 for various colorectal pathologies were studied. Fourteen patients had early colostomy closure while 23 had delayed closure. In the early colostomy closure group there were 10 men and 4 women. The mean age of the patients was 28yr with a range of 18-65yr. Colostomies were closed 9-18 days after initial colostomy construction. There was no mortality. Morbidity rate 28.6% (4 out of 14). There were two faecal fistulas (14.3%). Twenty-three patients had delayed colostomy closure 8 weeks to 18 months after initial colostomy construction. These were patients unfit for early surgery after initial colostomy construction because of carcinoma, significant weight loss, or sepsis. There was no mortality. Morbidity rate was 26.1%. There were 3 faecal fistulas (13.2%). Outcomes following early colostomy closure and delayed closure were comparable. Patients fit for surgery should have early closure whilst patients who may have compromised health should have delayed closure.

System for closure of a physical anomaly

DOEpatents

Bearinger, Jane P; Maitland, Duncan J; Schumann, Daniel L; Wilson, Thomas S

2014-11-11

Systems for closure of a physical anomaly. Closure is accomplished by a closure body with an exterior surface. The exterior surface contacts the opening of the anomaly and closes the anomaly. The closure body has a primary shape for closing the anomaly and a secondary shape for being positioned in the physical anomaly. The closure body preferably comprises a shape memory polymer.

Stapler vs suture closure of pancreatic remnant after distal pancreatectomy: a meta-analysis.

PubMed

Zhou, Wei; Lv, Ran; Wang, Xianfa; Mou, Yiping; Cai, Xiujun; Herr, Ingrid

2010-10-01

Suture closure and stapler closure of the pancreatic remnant after distal pancreatectomy are the techniques used most often. The ideal choice remains a matter of debate. Five bibliographic databases covering 1970 to July 2009 were searched. Sixteen articles met the inclusion criteria. Stapler closure was performed in 671 patients, while suture closure was conducted in 1,615 patients. The pancreatic fistula rate ranged from 0% to 40.0% for stapler closure of the pancreatic stump and from 9.3% to 45.7% for the suture closure technique. There were no significant difference between the stapler and suture closure groups with respect to the pancreatic fistula formation rate (22.1% vs 31.2%; odds ratio, .85; 95% confidence interval, .66-1.08), although there was a trend toward favoring stapler closure. In 4 studies including 437 patients, stapler closure was associated with a trend (not statistically significant) toward a reduction in intra-abdominal abscess (odds ratio, .53; 95% confidence interval, .24-1.15). No significant differences occur between suture and stapler closure with respect to the pancreatic fistula or intra-abdominal abscess after distal pancreatectomy, though there is a trend favoring stapler closure. Copyright © 2010 Elsevier Inc. All rights reserved.

Slip-additive migration, surface morphology, and performance on injection moulded high-density polyethylene closures.

PubMed

Dulal, Nabeen; Shanks, Robert; Gengenbach, Thomas; Gill, Harsharn; Chalmers, David; Adhikari, Benu; Pardo Martinez, Isaac

2017-11-01

The amount and distribution of slip agents, erucamide, and behenamide, on the surface of high-density polyethene, is determined by integral characteristics of slip agent structure and polymer morphology. A suite of surface analysis techniques was applied to correlate physicochemical properties with slip-additive migration behaviour and their surface morphology. The migration, surface morphology and physicochemical properties of the slip additives, crystallinity and orientation of polyethene spherulites and interaction between slip additives and high-density polyethene influence the surface characteristics. The high-density polyethene closures were produced with erucamide and behenamide separately and stored until they produced required torque. Surface composition was determined employing spectroscopy and gas chromatography. The distribution of additives was observed under optical, scanning electron and atomic force microscopes. The surface energy, crystallinity and application torque were measured using contact angle, differential scanning calorimeter and a torque force tester respectively. Each slip additive produced a characteristic amide peak at 1645cm -1 in infrared spectroscopy and peaks of oxygen and nitrogen in X-ray photoelectron spectroscopy, suggesting their presence on the surface. The erucamide produced placoid scale-like structures and behenamide formed denticulate structures. The surface erucamide and behenamide responsible for reducing the torque was found to be 15.7µg/cm 2 and 1.7µg/cm 2 . Copyright © 2017 Elsevier Inc. All rights reserved.

Microvascular Decompression for Trigeminal Neuralgia: Technical Refinement for Complication Avoidance.

PubMed

Tomasello, Francesco; Esposito, Felice; Abbritti, Rosaria V; Angileri, Filippo F; Conti, Alfredo; Cardali, Salvatore M; La Torre, Domenico

2016-10-01

Microvascular decompression (MVD) represents the most effective and safe surgical option for the treatment of trigeminal neuralgia since it was first popularized by Jannetta 50 years ago. Despite several advances, complications such as cerebellar and vascular injury, hearing loss, muscular atrophy, cerebrospinal fluid (CSF) leak, postoperative cutaneous pain, and sensory disturbances still occur and may negatively affect the outcome. We propose some technical nuances of the surgical procedure that were used in our recent series. We used a novel hockey stick-shaped retromastoid skin incision, preserving the major nerves of the occipital and temporal areas. Microsurgical steps were performed without the use of retractors. CSF leakage was prevented with a watertight dural closure and multilayer osteodural reconstruction. The refined surgical steps were perfected in the last consecutive 15 cases of our series. In these cases we did not record any cutaneous pain, sensory disturbances, or CSF leakage. The average diameter of the craniectomy was 18 mm. No patient reported major complications related to the intradural microsurgical maneuvers. In all cases the neurovascular conflict was found and solved with a good outcome in terms of pain disappearance. Our minimally invasive approach was demonstrated to guarantee an optimal exposure of the cerebellopontine angle and minimize the rate of complications related to skin incision and muscular dissection, microsurgical steps, and closure. Copyright © 2016 Elsevier Inc. All rights reserved.

Stump closure of a thick pancreas using stapler closure increases pancreatic fistula after distal pancreatectomy.

PubMed

Kawai, Manabu; Tani, Masaji; Okada, Ken-ichi; Hirono, Seiko; Miyazawa, Motoki; Shimizu, Astusi; Kitahata, Yuji; Yamaue, Hiroki

2013-09-01

The appropriate surgical stump closure after distal pancreatectomy (DP) is still controversial. This study investigated the benefits and risks of stapler closure during DP. The risk factors of pancreatic fistulas were investigated in 122 DPs among 3 types of stump closure: hand-sewn suture (n = 32), bipolar scissors (n = 45), and stapler closure (n = 45). There was no significant difference in the incidence of pancreatic fistula between the 3 types of stump closure (hand-sewn suture [44%] vs bipolar scissors [37.7%] vs stapler closure [35.5%]). By using receiver operating characteristics curves, 12 mm was the best cutoff value of the thickness of the pancreas for pancreatic fistulas after DP using stapler closure. Three factors (ie, male sex, body mass index >25 kg/m(2), and stapler closure) were independent risk factors of pancreatic fistulas after DP with a pancreas thicker than 12 mm. A pancreas thicker than 12 mm significantly increased the incidence of pancreatic fistulas after DP using stapler closure. Copyright © 2013 Elsevier Inc. All rights reserved.

Analysis of local delaminations caused by angle ply matrix cracks

NASA Technical Reports Server (NTRS)

Salpekar, Satish A.; Obrien, T. Kevin; Shivakumar, K. N.

1993-01-01

Two different families of graphite/epoxy laminates with similar layups but different stacking sequences, (0,theta,-theta) sub s and (-theta/theta/0) sub s were analyzed using three-dimensional finite element analysis for theta = 15 and 30 degrees. Delaminations were modeled in the -theta/theta interface, bounded by a matrix crack and the stress free edge. The total strain energy release rate, G, along the delamination front was computed using three different techniques: the virtual crack closure technique (VCCT), the equivalent domain Integral (EDI) technique, and a global energy balance technique. The opening fracture mode component of the strain energy release rate, Gl, along the delamination front was also computed for various delamination lengths using VCCT. The effect of residual thermal and moisture stresses on G was evaluated.

Theoretical study of interactions of BSA protein in a NaCl aqueous solution

NASA Astrophysics Data System (ADS)

Pellicane, Giuseppe; Cavero, Miguel

2013-03-01

Bovine Serum Albumine (BSA) aqueous solutions in the presence of NaCl are investigated for different protein concentrations and low to intermediate ionic strengths. Protein interactions are modeled via a charge-screened colloidal model, in which the range of the potential is determined by the Debye-Hückel constant. We use Monte Carlo computer simulations to calculate the structure factor, and assume an oblate ellipsoidal form factor for BSA. The theoretical scattered intensities are found in good agreement with the experimental small angle X-ray scattering intensities available in the literature. The performance of well-known integral equation closures to the Ornstein-Zernike equation, namely the mean spherical approximation, the Percus-Yevick, and the hypernetted chain equations, is also assessed with respect to computer simulation.

Retinal pigment epithelium changes in Kartagener syndrome.

PubMed

Garcia, Maria D; Ventura, Camila V; Dias, João R; Chang, Ta Chen P; Berrocal, Audina M

2018-06-01

We present the first case in the literature of a patient with Kartagener syndrome and ocular findings of nonexudative age-related macular degeneration. A 55-year-old woman with Kartagener syndrome and chronic angle closure glaucoma presented for evaluation of the retina. Optos ultra-widefield imaging of the fundus showed glaucomatous cupping, drusen, and retinal pigment epithelium changes within the macular region. Humphrey visual field testing confirmed glaucomatous changes. Drusenoid pigment epithelial detachments were observed bilaterally with optical coherence tomography. We hypothesize that in addition to the lungs, spermatozoa and the Fallopian tubes, the retinal pigment epithelium may also be affected by ciliary dysfunction in individuals with Kartagener syndrome. Given recent advances in our knowledge of retinal ciliopathies, further studies are needed to understand how ciliary dysfunction affects the retina in Kartagener syndrome.

40 CFR 264.258 - Closure and post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Waste Piles § 264.258 Closure and post-closure care. (a) At closure, the owner or operator must remove... that apply to landfills (§ 264.310). (c)(1) The owner or operator of a waste pile that does not comply...(c) or § 264.251(b), must: (i) Include in the closure plan for the pile under § 264.112 both a plan...

The Effect of Rural Hospital Closures on Community Economic Health

PubMed Central

Holmes, George M; Slifkin, Rebecca T; Randolph, Randy K; Poley, Stephanie

2006-01-01

Objective To examine the effect of rural hospital closures on the local economy. Data Sources U.S. Census Bureau, OSCAR, Medicare Cost Reports, and surveys of individuals knowledgeable about local hospital closures. Study Design Economic data at the county level for 1990–2000 were combined with information on hospital closures. The study sample was restricted to rural counties experiencing a closure during the sample period. Longitudinal regression methods were used to estimate the effect of hospital closure on per-capita income, unemployment rate, and other community economic measures. Models included both leading and lagged closure terms allowing a preclosure economic downturn as well as time for the closure to be fully realized by the community. Data Collection Information on closures was collected by contacting every state hospital association, reconciling information gathered with that contained in the American Hospital Association file and OIG reports. Principal Findings Results indicate that the closure of the sole hospital in the community reduces per-capita income by $703 (p<0.05) or 4 percent (p<0.05) and increases the unemployment rate by 1.6 percentage points (p<0.01). Closures in communities with alternative sources of hospital care had no long-term economic impact, although income decreased for 2 years following the closure. Conclusions The local economic effects of a hospital closure should be considered when regulations that affect hospitals' financial well-being are designed or changed. PMID:16584460

APPARATUS AND METHOD FOR WELDING END CLOSURE TO CONTAINER

DOEpatents

Frantz, C.E.; Correy, T.B.

1959-08-01

A semi-automatic apparatus is described for welding a closure to the open end of a can containing a nuclear fuel slug. An arc is struck at the center of the closure and is shifted to a region near its periphery. Then the assembly of closure, can, and fuel slug is rotated so that the peripheral region of the closure is preheated. Next the arc is shifted to the periphery itself of the closure, and the assembly is rotated so that the closure is welded to the can.

Positive Catch & Economic Benefits of Periodic Octopus Fishery Closures: Do Effective, Narrowly Targeted Actions 'Catalyze' Broader Management?

PubMed

Oliver, Thomas A; Oleson, Kirsten L L; Ratsimbazafy, Hajanaina; Raberinary, Daniel; Benbow, Sophie; Harris, Alasdair

2015-01-01

Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered ~20% of a village's fished area and lasted 2-7 months. Octopus landings and catch per unit effort (CPUE) significantly increased in the 30 days following a closure's reopening, relative to the 30 days before a closure (landings: +718%, p<0.0001; CPUE: +87%, p<0.0001; n = 36). Open-access control sites showed no before/after change when they occurred independently of other management ("no ban", n = 17/36). On the other hand, open-access control sites showed modest catch increases when they extended a 6-week seasonal fishery shutdown ("ban", n = 19/36). The seasonal fishery shutdown affects the entire region, so confound all potential control sites. In villages implementing a closure, octopus fishery income doubled in the 30 days after a closure, relative to 30 days before (+132%, p<0.001, n = 28). Control villages not implementing a closure showed no increase in income after "no ban" closures and modest increases after "ban" closures. Villages did not show a significant decline in income during closure events. Landings in closure sites generated more revenue than simulated landings assuming continued open-access fishing at that site (27/36 show positive net earnings; mean +$305/closure; mean +57.7% monthly). Benefits accrued faster than local fishers' time preferences during 17-27 of the 36 closures. High reported rates of illegal fishing during closures correlated with poor economic performance. We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing more comprehensive management.

Lace Up for Healthy Feet: The Impact of Shoe Closure on Plantar Stress Response.

PubMed

Rahemi, Hadi; Armstrong, David G; Enriquez, Ana; Owl, Joshua; Talal, Talal K; Najafi, Bijan

2017-07-01

This study examined the impact of shoe closure on plantar thermal stress response (TSR), which is known to be a surrogate of shear stress and skin perfusion. It is aimed to explore potential impact of shoe closure on increasing risk factors associated with plantar ulcers in people with diabetic peripheral neuropathy (DPN). Fifteen eligible subjects were enrolled. The left foot was used as a reference and fitted to a self-adjusted and habitual lace-tightening method by each subject. The right foot was used as a test closure and fitted into three lace closure conditions: loose, tight, and preset optimal closure (reel clutch, BOA technology). Thermal images were taken after 5 minutes of acclimatization (pre-trial) and immediately after 200 walking steps in each shoe closure condition (post-trial). TSR was calculated from the thermal images. TSR was significantly higher in the test closure with loose (70.24%, P = .000) and tight (66.85%, P = .007) and lower (-206.53%, P = .000) in the preset optimal closure when compared to the reference closure. Only lace closure conditions affected TSR with no significant impact from age, BMI, and gender in our sample in a multivariable regression model. The results from this study suggest that shoelace closure technique can have a profound effect on TSR. It therefore stands to reason that optimal lace closure may have an impact in reducing risk of plantar ulcers in people with DPN. Interestingly, results revealed that even a self-adjusted lace closure may not be necessarily optimal and a preset closure setting like reel clutch might ultimately be recommended to minimize risk. Further study is warranted to confirm or refute these interesting results.

[Factors influencing the prognosis of patent ductus arteriosus in very low birth weight infants].

PubMed

Wang, Chen-Hong; Shi, Li-Ping; Ma, Xiao-Lu; Luo, Fang; Chen, Zheng; Lin, Hui-Jia; DU, Li-Zhong

2016-08-01

To investigate the factors influencing the prognosis of patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants. A total of 194 VLBW infants who were admitted from January 2012 to December 2014 were enrolled as study subjects. According to cardiac ultrasound findings and treatment outcome, these infants were divided into non-PDA group, spontaneous closure group, pharmaceutical closure group, and surgical closure group. Their clinical and echocardiographic characteristics were analyzed. The spontaneous closure rate of PDA was 58.7%. The spontaneous closure group showed significantly higher gestational age, birth weight, and proportion of small-for-gestational-age infants than the pharmaceutical and surgical closure groups (P<0.05). The pharmaceutical and surgical closure groups had a significantly higher incidence rate of neonatal respiratory distress syndrome and a significantly higher proportion of infants who were given pulmonary surfactant (PS) than the spontaneous closure group (P<0.05). During different periods of time, the spontaneous closure group had a significantly smaller ductus arteriosus diameter than the pharmaceutical and surgical closure groups (P<0.05). The multivariate logistic regression analysis showed that gestational age, application of PS, and ductus arteriosus diameter at 48 hours were significantly associated with the prognosis of PDA. The major transductal flow pattern in the spontaneous closure group was closing pattern, while in the pharmaceutical and surgical closure groups, the main flow patterns were pulmonary hypertension and growing patterns within 48 hours and growing pattern on days 4 and 7. The VLBW infants have a high spontaneous closure rate of PDA. A decreased closure rate of PDA is associated with the lower gestational age and the application of PS. PDA with a large ductus arteriosus diameter and a growing or pulsatile flow pattern cannot easily achieve spontaneous closure.

40 CFR 264.280 - Closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...

40 CFR 264.280 - Closure and post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...

40 CFR 264.280 - Closure and post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...

40 CFR 264.280 - Closure and post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Land Treatment § 264.280 Closure and post-closure care. (a) During the closure period the owner or...

Metalloproteinase Expression is Associated with Traumatic Wound Failure

DTIC Science & Technology

2010-04-01

Traumatic amputation- no.(%) 15 Size of wound (cm3 )* Associated vascular injury- no.(%) 7 Wound closure method no.(%) Suture 29 Skin graft 9 Number...definitive closure or coverage with skin graft . Im- paired wound healing included delayed wound closure or wound dehiscence after closure or coverage...closure time period of 10 d. Dehiscence was defined as spontaneous partial or com- plete wound disruption after primary closure or > 90% skin graft loss

Novel application of polyelectrolyte multilayers as nanoscopic closures with hermetic sealing.

PubMed

Marcott, Stephanie A; Ada, Sena; Gibson, Phillip; Camesano, Terri A; Nagarajan, R

2012-03-01

Closure systems for personnel protection applications, such as protective clothing or respirator face seals, should provide effective permeation barrier to toxic gases. Currently available mechanical closure systems based on the hook and loop types (example, Velcro) do not provide adequate barrier to gas permeation. To achieve hermetic sealing, we propose a nonmechanical, nanoscopic molecular closure system based on complementary polyelectrolyte multilayers, one with a polycation outermost layer and the other with a polyanion outermost layer. The closure surfaces were prepared by depositing polyelectrolyte multilayers under a variety of deposition conditions, on conformable polymer substrates (thin films of polyethylene teraphthalate, PET or polyimide, PI). The hermetic sealing property of the closures was evaluated by measuring the air flow resistance using the dynamic moisture permeation cell (DMPC) at different humidity conditions. The DMPC measurements show that the polyelectrolyte multilayer closures provide significantly large resistance to air flow, approximately 20-800 times larger than that possible with conventional hook and loop type closure systems, at all humidity levels (from 5 to 95% relative humidity). Hence, from the point of view of providing a hermetic seal against toxic gas permeation, the polyelectrolyte multilayer closures are viable candidates for further engineering development. However, the adhesive strength of the multilayer closures measured by atomic force microscopy suggests that the magnitude of adhesion is much smaller than what is possible with mechanical closures. Therefore, we envisage the development of a composite closure system combining the mechanical closure to provide strong adhesion and the multilayer closure to provide hermetic sealing. © 2012 American Chemical Society

32 CFR 989.25 - Base closure and realignment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 32 National Defense 6 2013-07-01 2013-07-01 false Base closure and realignment. 989.25 Section 989... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure...

32 CFR 989.25 - Base closure and realignment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 32 National Defense 6 2012-07-01 2012-07-01 false Base closure and realignment. 989.25 Section 989... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure...

Household responses to school closure resulting from outbreak of influenza B, North Carolina.

PubMed

Johnson, April J; Moore, Zack S; Edelson, Paul J; Kinnane, Lynda; Davies, Megan; Shay, David K; Balish, Amanda; McCarron, Meg; Blanton, Lenee; Finelli, Lyn; Averhoff, Francisco; Bresee, Joseph; Engel, Jeffrey; Fiore, Anthony

2008-07-01

School closure is a proposed strategy for reducing influenza transmission during a pandemic. Few studies have assessed how families respond to closures, or whether other interactions during closure could reduce this strategy's effect. Questionnaires were administered to 220 households (438 adults and 355 children) with school-age children in a North Carolina county during an influenza B virus outbreak that resulted in school closure. Closure was considered appropriate by 201 (91%) households. No adults missed work to solely provide childcare, and only 22 (10%) households required special childcare arrangements; 2 households incurred additional costs. Eighty-nine percent of children visited at least 1 public location during the closure despite county recommendations to avoid large gatherings. Although behavior and attitudes might differ during a pandemic, these results suggest short-term closure did not cause substantial hardship for parents. Pandemic planning guidance should address the potential for transmission in public areas during school closure.

Seven-year follow-up of percutaneous closure of patent foramen ovale.

PubMed

Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Johansson, Magnus Carl; Furenäs, Eva; Eriksson, Peter; Dellborg, Mikael

2013-12-01

Observational studies favor percutaneous closure of patent foramen ovale (PFO) over medical treatment to reduce recurrent stroke while randomized trials fail to demonstrate significant superiority of percutaneous PFO closure. Few long-term studies are available post PFO closure. This study reports long-term clinical outcomes after percutaneous PFO closure. Between 1997 and 2006, 86 consecutive eligible patients with cerebrovascular events, presumably related to PFO, underwent percutaneous PFO closure. All 86 patients were invited to a long-term follow-up, which was carried out during 2011 and 2012. Percutaneous PFO closure was successfully performed in 85 of 86 patients. The follow-up rate was 100%. No cardiovascular or cerebrovascular deaths occurred. Two patients (both women) died from lung cancer during follow-up. Follow-up visits were conducted for 64 patients and the remaining 20 patients were followed up by phone. The mean follow-up time was 7.3 years (5 to 12.4 years). Mean age at PFO closure was 49 years. One patient had a minor stroke one month after PFO closure and a transient ischemic attack (TIA) two years afterwards. One other patient suffered from a TIA six years after closure. No long-term device-related complications were observed. Percutaneous PFO closure was associated with very low risk of recurrent stroke and is suitable in most patients. We observed no mortality and no long-term device-related complications related to PFO closure, indicating that percutaneous PFO closure is a safe and efficient treatment even in the long term.

Patent foramen ovale closure and medical treatments for secondary stroke prevention: a systematic review of observational and randomized evidence.

PubMed

Kitsios, Georgios D; Dahabreh, Issa J; Abu Dabrh, Abd Moain; Thaler, David E; Kent, David M

2012-02-01

Patients discovered to have a patent foramen ovale in the setting of a cryptogenic stroke may be treated with percutaneous closure, antiplatelet therapy, or anticoagulants. A recent randomized trial (CLOSURE I) did not detect any benefit of closure over medical treatment alone; the optimal medical therapy is also unknown. We synthesized the available evidence on secondary stroke prevention in patients with patent foramen ovale and cryptogenic stroke. A MEDLINE search was performed for finding longitudinal studies investigating medical treatment or closure, meta-analysis of incidence rates (IR), and IR ratios of recurrent cerebrovascular events. Fifty-two single-arm studies and 7 comparative nonrandomized studies and the CLOSURE I trial were reviewed. The summary IR of recurrent stroke was 0.36 events (95% confidence interval [CI], 0.24-0.56) per 100 person-years with closure versus 2.53 events (95% CI, 1.91-3.35) per 100 person-years with medical therapy. In comparative observational studies, closure was superior to medical therapy (IR ratio=0.19; 95% CI, 0.07-0.54). The IR for the closure arm of the CLOSURE I trial was higher than the summary estimate from observational studies; there was no significant benefit of closure over medical treatment (P=0.002 comparing efficacy estimates between observational studies and the trial). Observational and randomized data (9 studies) comparing medical therapies were consistent and suggested that anticoagulants are superior to antiplatelets for preventing stroke recurrence (IR ratio=0.42; 95% CI, 0.18-0.98). Although further randomized trial data are needed to precisely determine the effects of closure on stroke recurrence, the results of CLOSURE I challenge the credibility of a substantial body of observational evidence strongly favoring mechanical closure over medical therapy.

Closure Report for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks, Nevada Test Site, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

NSTec Environmental Restoration

CAU 127, Areas 25 and 26 Storage Tanks, consists of twelve CASs located in Areas 25 and 26 of the NTS. The closure alternatives included no further action, clean closure, and closure in place with administrative controls. The purpose of this Closure Report is to provide a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.

40 CFR 265.1202 - Closure and post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... post-closure care. (a) At closure of a magazine or unit which stored hazardous waste under this subpart... estimates for closure, and financial responsibility for magazines or units must meet all of the requirements... as long as it remains in service as a munitions or explosives magazine or storage unit. (b) If, after...

Characterization of ocular biometrics and aqueous humor dynamics in primary angle closure suspects.

PubMed

Guo, Li; Deng, Yuan; Fang, Li; Liu, Chaoqi; Guo, Tao

2017-02-01

Detailed characterizations of ocular biometrics and parameters of aqueous humor dynamics are lacking in primary angle closure suspect (PACS) patients. This study aims to characterize these parameters and compare them with age-matched healthy volunteers.Elderly healthy volunteers (60.6 ± 7.2 years of age, mean ± SD, n = 28) and PACS patients (64.1 ± 11.6 years, n = 30) completed the study. Parameters investigated were axial length (AXL), anterior chamber depth (ACD), anterior chamber volume (ACV), central cornea thickness (CCT), intraocular pressure (IOP), aqueous flow (Fa), outflow facility (C), episcleral venous pressure (EVP), and uveoscleral outflow (Fu). Comparisons and correlations were made between and within groups.In healthy volunteers, ocular biometric parameters, IOP, and EVP correlated very well between the 2 eyes of each individual, but Fa, C, and Fu were not significantly correlated. Biometric parameters of the PACS group significantly (P < 0.001) differed from those of the healthy controls: AXL (23.31 ± 1.03 mm [PACS] vs 22.39 ± 1.04 mm [Control]; mean ± SD), ACD (2.44 ± 0.33 mm [PACS] vs 1.86 ± 0.25 mm [Control]), ACV (136.0 ± 36.1 μL [PACS] vs 81.4 ± 21.8 μL [Control]), CCT (526.9 ± 37.0 μm [PACS] vs 556.1 ± 28.4 μm [Control]). There was no significant change in IOP, Fa, C, EVP, or Fu between Control and PACS. Furthermore, IOP showed no significant correlations with AXL, ACD, ACV, CCT, or C in both groups.The PACS eyes had a shorter AXL, a shallower ACD, and a smaller ACV, but a thicker CCT. Despite these morphological changes, the PACS eyes did not have any significant changes in IOP, and aqueous humor dynamics parameters. This is consistent with the findings that IOP did not show significant correlations with biometrics, or C.

Ethnic differences in lens parameters measured by ocular biometry in a cataract surgery population.

PubMed

Wang, Dajiang; Amoozgar, Behzad; Porco, Travis; Wang, Zhen; Lin, Shan C

2017-01-01

To investigate whether differences exist in lens position and other lens parameters among major ethnic groups with cataractous eyes, which may help explain racial differences in angle closure risk. This retrospective, cross-sectional study included 807 adult patients who had cataract surgery between years 2014 and 2016 at the University of California, San Francisco (UCSF). Adult patients of white, Asian, Hispanic and African-American ethnicity were included. Lens position (LP), defined as anterior chamber depth (ACD) + 1/2 lens thickness (LT), was assessed using measurements from optical biometry. Other assessed biometric parameters included axial length (AL), relative lens position (RLP) (defined as LP/AL), and anterior chamber depth (ACD). A total of 807 patients and 1361 eyes were included in this study from a database of patients having cataract surgery. Mean age was 69.2 years (age range from 18 to 101 years old), and 60.3% of patients were women. The mean LP measurements were 5.54±0.32 mm for white, 5.38±0.32 mm for Asian, 5.32±0.30 mm for Hispanic, and 5.40±0.28 mm for African-American participants. After adjusting for age, sex, and AL, significant differences were found when comparing LP in paired comparisons among White cohort with Asians (P<0.001), Hispanics (P<0.001) and African-Americans (P = 0.003). Additionally, when comparing RLP, similar significant results were found when comparing Whites with Asians (P<0.001), Hispanics (P<0.001) and African-Americans (P = 0.002). Lastly, pair-wise comparison of LT between ethnic groups showed significant differences while comparing Asians with Whites (P = 0.001) and Asians with African-Americans (P<0.001). The results of this study suggest that the LP of Hispanic, Asian, and African-American patients are significantly smaller than that of White patients, and among all ethnic groups, Hispanics and after Asians have the smallest LP (P<0.001) and RLP (P<0.001). These findings may have implications for the relative risk of angle closure and the potential IOP response after cataract surgery among different ethnic groups.

A prospective study of two methods of closing surgical scalp wounds.

PubMed

Adeolu, A A; Olabanji, J K; Komolafe, E O; Ademuyiwa, A O; Awe, A O; Oladele, A O

2012-02-01

Scalp wounds are commonly closed in two layers, although single layer closure is feasible. This study prospectively compared the two methods of closing scalp wounds. Patients with non-traumatic scalp wounds were allocated to either the single layer closure group or the multilayer closure group. We obtained relevant data from the patients. The primary outcome measures were wound edge related complications, rate of suturing and cost of sutures used for suturing. Thirty-one wounds were in the single layer closure group and 30 were in the multilayer closure group. Age range was 1-80 years. The most common indication for making a scalp incision was subdural hematoma, representing 27.8% of all the indications. The most common surgery was burr hole drainage of subdural hematoma. Polyglactin acid suture was used for the inner layer and polyamide -00- for the final layer in the multilayer closure group. Only the latter suture was used for the single layer closure method. Total cost of suturing per wound in the single layer closure group was N= 100 (0.70USD) and N= 800 (5.30USD) in the multilayer group. The mean rate of closure was 0.39 ± 1.89 mm/sec for single layer closure and 0.23 ± 0.89 mm/sec in multilayer closure. The difference was statistically significant. Wound edge related complication rate was 19.35% in the single layer closure group and 16.67% in the multilayer closure method group. The difference was not statistically significant (z: 0.00, p value: 1.000; Pearson chi-squared (DF = 1)= 0.0075, p = 0.0785). The study shows that closing the scalp in one layer is much faster and more cost effective compared to the multilayer closure method. We did not observe significant difference in the complication rates in the two methods of closure. Long-term outcome, especially cosmetic outcome, remains to be determined in this preliminary study.

Evaluation of left ventricular function by tissue Doppler and speckle-derived strain rate echocardiography after percutaneous ductus closure.

PubMed

Amoogzar, Hamid; Shakiba, Ali Mohammad; Derakhshan, Dorna; Ajami, Gholamhossein; Cheriki, Sirous; Borzouee, Mohammad; Edraki, Mohammad Reza; Mehdizadegan, Nima

2015-01-01

The aim of this study was to evaluate the left ventricular systolic and diastolic function before and after transcatheter percutaneous patent ductus arteriosus (PDA) closure. 21 children (age >6 months old) diagnosed with hemodynamically significant PDA underwent percutaneous PDA closure. Conventional, Doppler and tissue Doppler imaging and speckled-derived strain rate echocardiography were done at pre-closure, 1 day (early) and 1 month (late) post-closure. Mean age of the patients (female/male: 1.3) was 17.54 ± 24.7 months with the mean PDA diameter of 3.6 ± 0.8 mm. Systolic measures (ejection fraction, shortening fraction) reduced significantly early after PDA closure (P < 0.05). After 1 month, both improved significantly; ultimately, after 1 month no change was observed in systolic function measures compared with the pre-closure status. Early and late diastolic flow velocities of mitral (E M and A M) reduced considerably in early and late post-closure time (P < 0.05). Both early tissue Doppler early velocity of lateral mitral annulus (E'M) and early to late velocity ratio (E'M/A'M) of lateral mitral annulus decreased significantly (P = 0.02) in early post-closure. After 1 month, E'M increased considerably. (P = 0.01) but E'M/A'M had an insignificant rise (P > 0.05). E M/E'M ratio did not change in early post-closure but it had a considerable reduction in the subsequent month compared with the pre- and early post-closure (P < 0.001 for both occasions). Global and segmental longitudinal strain measures reduced significantly early after PDA closure (P < 0.05) but it improved remarkably in the subsequent month. Transcatheter PDA closure causes a significant decrease in left ventricular performance early after PDA closure which recovers completely within 1 month. Also PDA size can affect post-closure left ventricular function.

Primary closure versus delayed closure for non bite traumatic wounds within 24 hours post injury.

PubMed

Eliya-Masamba, Martha C; Banda, Grace W

2013-10-22

Acute traumatic wounds are one of the common reasons why people present to the emergency department. Primary closure has traditionally been reserved for traumatic wounds presenting within six hours of injury and considered 'clean' by the attending surgeon, with the rest undergoing delayed primary closure as a means of controlling wound infection. Primary closure has the potential benefit of rapid wound healing but poses the potential threat of increased wound infection. There is currently no evidence to guide clinical decision-making on the best timing for closure of traumatic wounds. To determine the effect on time to healing of primary closure versus delayed closure for non bite traumatic wounds presenting within 24 hours post injury. To explore the adverse effects of primary closure compared with delayed closure for non bite traumatic wounds presenting within 24 hours post injury. In May 2013, for this first update we searched the Cochrane Wounds Group Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL. There were no restrictions with respect to language, date of publication or study setting. Randomised controlled trials comparing primary closure with delayed closure of non bite traumatic wounds. Two review authors independently evaluated the results of the searches against the inclusion criteria. No studies met the inclusion criteria for this review. Since no studies met the inclusion criteria, neither a meta-analysis nor a narrative description of studies was possible. There is currently no systematic evidence to guide clinical decision-making regarding the timing for closure of traumatic wounds. There is a need for robust research to investigate the effect of primary closure compared with delayed closure for non bite traumatic wounds presenting within 24 hours of injury.

CLOSURE REPORT FOR CORRECTIVE ACTION UNIT 528: POLYCHLORINATED BIPHENYLS CONTAMINATION NEVADA TEST SITE, NEVADA

DOE Office of Scientific and Technical Information (OSTI.GOV)

BECHTEL NEVADA

2006-09-01

This Closure Report (CR) describes the closure activities performed at CAU 528, Polychlorinated Biphenyls Contamination, as presented in the Nevada Division of Environmental Protection (NDEP)-approved Corrective Action Plan (CAP) (US. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSAINSO], 2005). The approved closure alternative was closure in place with administrative controls. This CR provides a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.

Umbilical hernia following gastroschisis closure: a common event?

PubMed

Tullie, L G C; Bough, G M; Shalaby, A; Kiely, E M; Curry, J I; Pierro, A; De Coppi, P; Cross, K M K

2016-08-01

To assess incidence and natural history of umbilical hernia following sutured and sutureless gastroschisis closure. With audit approval, we undertook a retrospective clinical record review of all gastroschisis closures in our institution (2007-2013). Patient demographics, gastroschisis closure method and umbilical hernia occurrence were recorded. Data, presented as median (range), underwent appropriate statistical analysis. Fifty-three patients were identified, gestation 36 weeks (31-38), birth weight 2.39 kg (1-3.52) and 23 (43 %) were male. Fourteen patients (26 %) underwent sutureless closure: 12 primary, 2 staged; and 39 (74 %) sutured closure: 19 primary, 20 staged. Sutured closure was interrupted sutures in 24 patients, 11 pursestring and 4 not specified. Fifty patients were followed-up over 53 months (10-101) and 22 (44 %) developed umbilical hernias. There was a significantly greater hernia incidence following sutureless closure (p = 0.0002). In sutured closure, pursestring technique had the highest hernia rate (64 %). Seven patients underwent operative hernia closure; three secondary to another procedure. Seven patients had their hernias resolve. One patient was lost to follow-up and seven remain under observation with no reported complications. There is a significant umbilical hernia incidence following sutureless and pursestring sutured gastroschisis closure. This has not led to complications and the majority have not undergone repair.

Identification of Selected Child-Resistant Closures (Continuous Thread, Lug-Bayonet, and Snap Closures).

ERIC Educational Resources Information Center

Gross, Rosalind L.; White, Harry E.

This publication describes a selected group of child-resistant closures used in packaging five categories of medicine and household products. The material in the document was collected to train survey personnel to identify closures for a planned household study of the effectiveness of child-resistant packaging. The 39 closures described are of…

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2012 CFR

2012-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2013 CFR

2013-04-01

... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2014 CFR

2014-04-01

... OF THE TREASURY ALCOHOL LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

27 CFR 26.136 - Affixing closures.

Code of Federal Regulations, 2011 CFR

2011-04-01

... OF THE TREASURY LIQUORS LIQUORS AND ARTICLES FROM PUERTO RICO AND THE VIRGIN ISLANDS Closures for Distilled Spirits From Puerto Rico § 26.136 Affixing closures. Closures or other devices shall be securely...

Platelets contribute to postnatal occlusion of the ductus arteriosus.

PubMed

Echtler, Katrin; Stark, Konstantin; Lorenz, Michael; Kerstan, Sandra; Walch, Axel; Jennen, Luise; Rudelius, Martina; Seidl, Stefan; Kremmer, Elisabeth; Emambokus, Nikla R; von Bruehl, Marie-Luise; Frampton, Jon; Isermann, Berend; Genzel-Boroviczény, Orsolya; Schreiber, Christian; Mehilli, Julinda; Kastrati, Adnan; Schwaiger, Markus; Shivdasani, Ramesh A; Massberg, Steffen

2010-01-01

The ductus arteriosus (DA) is a fetal shunt vessel between the pulmonary artery and the aorta that closes promptly after birth. Failure of postnatal DA closure is a major cause of morbidity and mortality particularly in preterm neonates. The events leading to DA closure are incompletely understood. Here we show that platelets have an essential role in DA closure. Using intravital microscopy of neonatal mice, we observed that platelets are recruited to the luminal aspect of the DA during closure. DA closure is impaired in neonates with malfunctioning platelet adhesion or aggregation or with defective platelet biogenesis. Defective DA closure resulted in a left-to-right shunt with increased pulmonary perfusion, pulmonary vascular remodeling and right ventricular hypertrophy. Our findings indicate that platelets are crucial for DA closure by promoting thrombotic sealing of the constricted DA and by supporting luminal remodeling. A retrospective clinical study revealed that thrombocytopenia is an independent predictor for failure of DA closure in preterm human newborns, indicating that platelets are likely to contribute to DA closure in humans.

Impact of Vial Capping on Residual Seal Force and Container Closure Integrity.

PubMed

Mathaes, Roman; Mahler, Hanns-Christian; Roggo, Yves; Ovadia, Robert; Lam, Philippe; Stauch, Oliver; Vogt, Martin; Roehl, Holger; Huwyler, Joerg; Mohl, Silke; Streubel, Alexander

2016-01-01

The vial capping process is a critical unit operation during drug product manufacturing, as it could possibly generate cosmetic defects or even affect container closure integrity. Yet there is significant variability in capping equipment and processes, and their relation to potential defects or container closure integrity has not been thoroughly studied. In this study we applied several methods-residual seal force tester, a self-developed system of a piezo force sensor measurement, and computed tomography-to characterize different container closure system combinations that had been sealed using different capping process parameter settings. Additionally, container closure integrity of these samples was measured using helium leakage (physical container closure integrity) and compared to characterization data. The different capping equipment settings lead to residual seal force values from 7 to 115 N. High residual seal force values were achieved with high capping pre-compression force and a short distance between the capping plate and plunge. The choice of container closure system influenced the obtained residual seal force values. The residual seal force tester and piezoelectric measurements showed similar trends. All vials passed physical container closure integrity testing, and no stopper rupture was seen with any of the settings applied, suggesting that container closure integrity was warranted for the studied container closure system with the chosen capping setting ranges. The vial capping process is a critical unit operation during drug product manufacturing, as it could possibly generate cosmetic defects or even affect container closure integrity. Yet there is significant variability in capping equipment and processes, and their relation to potential defects or container closure integrity has not been thoroughly studied. In this study we applied several methods-residual seal force tester, a self-developed system of a piezo force sensor measurement, and computed tomography-to characterize different container closure system combinations that had been sealed using different capping process parameter settings. The residual seal force tester can analyze a variety of different container closure systems independent of the capping equipment. An adequate and safe residual seal force range for each container closure system configuration can be established with the residual seal force tester and additional methods like computed tomography scans and leak testing. In the residual seal force range studied, the physical container closure integrity of the container closure system was warranted. © PDA, Inc. 2016.

Mitomycin-augmented non-penetrating deep sclerectomy: preoperative gonioscopy and postoperative perimetric, tonometric and medication trends.

PubMed

Sponsel, William Eric; Groth, Sylvia Linner

2013-03-01

Non-penetrating deep sclerectomy (NPDS) can enhance drainage of aqueous humour without disrupting the trabecular endothelial layer, reducing risks of postoperative hypotony and hyphema. This study explores associations of angle morphology with surgical efficacy in eyes with open and obstructed angles. Eighty-nine consecutive eyes undergoing successful NPDS (non-implant, with 0.4 mg/ml mitomycin C and limbus-based two-layer closure) were studied in this institutional review board-approved retrospective quality assurance study. Postoperative complication frequency, intraocular pressure (IOP), glaucoma medications required and acuity were monitored (baseline vs 3, 6, 9, 12 and 18-month postoperative levels), along with 30-2 Humphrey MD and corrected pattern standard deviation (CPSD) (baseline vs 6, 12 and 18-month postoperative values). Preoperative gonioscopy was compared with the subsequent requirement for specific postoperative interventions. IOP at all five postoperative intervals was reduced (22 ± 0.9 to 12 ± 0.5 mm Hg; p<0.0001). No hyphema were observed. Postoperative hypotony (IOP < 4 mm Hg) occurred rarely (8/445; 1.8%). Mean glaucoma medication use dropped from 3.1 ± 0.1 to 0.23 ± 0.1 at 18 months (p<0.0001). Mean 30-2 MD improved by approximately 1.4 dB at 6, 12 and 18 months (p<0.002); CPSD remained stable. Following NPDS, a sustained IOP decrease of 10 mm Hg (45%) was attained, with stable acuity, increased perimetric generalised light sensitivity and 90% reduction in medical therapy requirement. Morbidity risk was associated with narrow gonioscopic angle insertion and synechia, but not with shallow approach or trabecular pigmentation.

Regional neural tube closure defined by the Grainy head-like transcription factors.

PubMed

Rifat, Yeliz; Parekh, Vishwas; Wilanowski, Tomasz; Hislop, Nikki R; Auden, Alana; Ting, Stephen B; Cunningham, John M; Jane, Stephen M

2010-09-15

Primary neurulation in mammals has been defined by distinct anatomical closure sites, at the hindbrain/cervical spine (closure 1), forebrain/midbrain boundary (closure 2), and rostral end of the forebrain (closure 3). Zones of neurulation have also been characterized by morphologic differences in neural fold elevation, with non-neural ectoderm-induced formation of paired dorso-lateral hinge points (DLHP) essential for neural tube closure in the cranial and lower spinal cord regions, and notochord-induced bending at the median hinge point (MHP) sufficient for closure in the upper spinal region. Here we identify a unifying molecular basis for these observations based on the function of the non-neural ectoderm-specific Grainy head-like genes in mice. Using a gene-targeting approach we show that deletion of Grhl2 results in failed closure 3, with mutants exhibiting a split-face malformation and exencephaly, associated with failure of neuro-epithelial folding at the DLHP. Loss of Grhl3 alone defines a distinct lower spinal closure defect, also with defective DLHP formation. The two genes contribute equally to closure 2, where only Grhl gene dosage is limiting. Combined deletion of Grhl2 and Grhl3 induces severe rostral and caudal neural tube defects, but DLHP-independent closure 1 proceeds normally in the upper spinal region. These findings provide a molecular basis for non-neural ectoderm mediated formation of the DLHP that is critical for complete neuraxis closure. (c) 2010 Elsevier Inc. All rights reserved.

Avoiding Accountability: How Charter Operators Evade Ohio's Automatic Closure Law. K-12 Education

ERIC Educational Resources Information Center

DePaoli, Jennifer; van Lier, Piet

2013-01-01

Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. Ohio's charter-closure law, which became effective in 2008 and was revised in 2011, calls for automatic closure of schools rated in Academic Emergency for at least…

77 FR 75186 - Notice of Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-19

... Closure, Target Shooting Public Safety Closure on the Lake Mountains in Utah County, UT AGENCY: Bureau of... Lake Mountains in Utah County, Utah, to recreational target shooting to protect public safety. This... shooting closure within the described area will remain in effect no longer than two years from December 19...

76 FR 20633 - Record of Decision (ROD) for the Base Closure and Realignment (BRAC) 2005 Actions at Fort...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... DEPARTMENT OF DEFENSE Department of the Army Record of Decision (ROD) for the Base Closure and... decision on how to implement property disposal in accordance with the Defense Base Closure and Realignment Act of 1990 (the Base Closure Act), Public Law 101-510, as amended, following the closure of Fort...

75 FR 26889 - Airworthiness Directives; Arrow Falcon Exporters, Inc. (previously Utah State University) et al...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-13

... the forward tip weight retention block (tip block) or aft tip closure (tip closure), loss of the blade...) forward tip weight retention block (tip block) and the aft tip closure (tip closure) for adhesive bond... prevent loss of a tip block or tip closure, loss of a blade, and subsequent loss of control of the...

Percutaneous device closure of atrial septal defect results in very early and sustained changes of right and left heart function.

PubMed

Monfredi, Oliver; Luckie, Matthew; Mirjafari, Hoda; Willard, Terence; Buckley, Helen; Griffiths, Linda; Clarke, Bernard; Mahadevan, Vaikom S

2013-08-20

To investigate the echocardiographic effects of percutaneous closure of secundum atrial septal defect (ASD) in adults and assess which pre-closure parameters predict good response to closure. ASD is a common congenital heart disease often undiscovered until adulthood. ASD closure has been revolutionized by the use of percutaneous devices. The effects of these procedures on echocardiographic parameters are not well characterized. Patients undergoing percutaneous device closure of ASD between June 2007 and June 2009 had 3 sequential echocardiograms reviewed: pre-procedure, immediate post-procedure (24 hours) and 6-8 weeks post-procedure. Significant changes from baseline were investigated using paired t-test/1-way ANOVA. Pearson correlation (2-tailed) tests were used to categorize patients as 'good responders' to closure in terms of selected parameters. 129 echocardiograms in 43 consecutive patients were included. Remodeling of both ventricles occurred immediately following ASD closure and was sustained. Right ventricular (RV) diameter in diastole decreased by 13.5% and 19.3% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05); Left ventricular (LV) diameter in diastole increased by 8.5% and 15.6%, respectively (p<0.05). Functional parameters of the RV also demonstrated early and sustained decreases (TAPSE decreased by 8.3% and 17% compared to baseline at 24 hours and 6-8 weeks post-closure, respectively (p<0.05)). Smaller RV baseline diameter appeared to predict good response to closure. Percutaneous ASD closure has immediate, sustained benefits on multiple echocardiographic parameters. Good responders have smaller RV at baseline, suggesting early closure is preferable. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

40 CFR 264.1202 - Closure and post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...

40 CFR 264.1202 - Closure and post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...

40 CFR 264.1202 - Closure and post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...

40 CFR 264.1202 - Closure and post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... FACILITIES Hazardous Waste Munitions and Explosives Storage § 264.1202 Closure and post-closure care. (a) At... it remains in service as a munitions or explosives magazine or storage unit. (b) If, after removing...

Analytical and Experimental Study of Near-Threshold Interactions Between Crack Closure Mechanisms

NASA Technical Reports Server (NTRS)

Newman, John A.; Riddell, William T.; Piascik, Robert S.

2003-01-01

The results of an analytical closure model that considers contributions and interactions between plasticity-, roughness-, and oxide-induced crack closure mechanisms are presented and compared with experimental data. The analytical model is shown to provide a good description of the combined influences of crack roughness, oxide debris, and plasticity in the near-threshold regime. Furthermore, analytical results indicate that closure mechanisms interact in a non-linear manner such that the total amount of closure is not the sum of closure contributions for each mechanism.

A comparison of two endoscopic closures: over-the-scope clip (OTSC) versus KING closure (endoloop + clips) in a randomized long-term experimental study.

PubMed

Dolezel, R; Ryska, O; Kollar, M; Juhasova, J; Kalvach, J; Ryska, M; Martinek, J

2016-11-01

Both over-the-scope clip (OTSC) and KING (endoloop + clips) closures provide reliable and safe full-thickness endoscopic closure. Nevertheless, OTSC clip demonstrated significantly inferior histological healing in the short-term follow-up. To compare OTSC versus KING closure of a perforation with regard to long-term effectiveness and macroscopic and histological quality of healing. We performed a randomized experimental study with 16 mini-pigs (mean weight 43.2 ± 11.2 kg). A standardized perforation was performed on the anterior sigmoid wall. KING closure (n = 8) was attained by approximation of an endoloop fixed to the margins of a perforation with endoclips. OTSC closure (n = 8) was performed by deploying OTSC (OVESCO) over the defect. Pigs underwent a control sigmoidoscopy 8 months after the closure to assess the macroscopic quality of healing. Then, autopsy was performed and the rectosigmoid was sent for histopathological assessment. All closures were completed successfully without air leaks. The duration of closure was similar in both techniques (OTSC 17.8 ± 7.6 min vs. KING 19.6 ± 8.8 min). At autopsy, all KING closures (100 %) were healed with a flat scar without signs of leakage. Microscopically, no inflammatory changes were observed after KING closure. In the OTSC group, microscopic ulcers were present in two pigs (25 %), cryptal abscesses in three pigs (38 %) and significant neutrophil accumulation in all eight pigs (P < 0.01). Giant cell granulomas, dysplasia or abundant scarification was not observed in either group. Both OTSC and KING closures offer a long-term reliable seal of a gastrointestinal perforation without stenosis or fistulas. KING closure provides long-term histologically superior healing.

Positive Catch & Economic Benefits of Periodic Octopus Fishery Closures: Do Effective, Narrowly Targeted Actions ‘Catalyze’ Broader Management?

PubMed Central

Oliver, Thomas A.; Oleson, Kirsten L. L.; Ratsimbazafy, Hajanaina; Raberinary, Daniel; Benbow, Sophie; Harris, Alasdair

2015-01-01

Overview Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered ~20% of a village’s fished area and lasted 2-7 months. Fishery Catches from Each Closed Site Octopus landings and catch per unit effort (CPUE) significantly increased in the 30 days following a closure’s reopening, relative to the 30 days before a closure (landings: +718%, p<0.0001; CPUE: +87%, p<0.0001; n = 36). Open-access control sites showed no before/after change when they occurred independently of other management (“no ban”, n = 17/36). On the other hand, open-access control sites showed modest catch increases when they extended a 6-week seasonal fishery shutdown (“ban”, n = 19/36). The seasonal fishery shutdown affects the entire region, so confound all potential control sites. Fishery Income in Implementing Villages In villages implementing a closure, octopus fishery income doubled in the 30 days after a closure, relative to 30 days before (+132%, p<0.001, n = 28). Control villages not implementing a closure showed no increase in income after “no ban” closures and modest increases after “ban” closures. Villages did not show a significant decline in income during closure events. Net Economic Benefits from Each Closed Site Landings in closure sites generated more revenue than simulated landings assuming continued open-access fishing at that site (27/36 show positive net earnings; mean +$305/closure; mean +57.7% monthly). Benefits accrued faster than local fishers’ time preferences during 17-27 of the 36 closures. High reported rates of illegal fishing during closures correlated with poor economic performance. Broader Co-Management We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing more comprehensive management. PMID:26083862

The TopClosure® 3S System, for skin stretching and a secure wound closure.

PubMed

Topaz, Moris; Carmel, Narin-Nard; Silberman, Adi; Li, Ming Sen; Li, Yong Zhong

2012-07-01

The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure® for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure® device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure® was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure® was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure® was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure®, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner.

Substantial Impact of School Closure on the Transmission Dynamics during the Pandemic Flu H1N1-2009 in Oita, Japan

PubMed Central

2015-01-01

Background School closure is considered as an effective measure to prevent pandemic influenza. Although Japan has implemented many class, grade, and whole school closures during the early stage of the pandemic 2009, the effectiveness of such a school closure has not been analysed appropriately. In addition, analysis based on evidence or data from a large population has yet to be performed. We evaluated the preventive effect of school closure against the pandemic (H1N1) 2009 and examined efficient strategies of reactive school closure. Materials and Methods Data included daily reports of reactive school closures and the number of infected students in the pandemic in Oita City, Japan. We used a regression model that incorporated a time delay to analyse the daily data of school closure based on a time continuous susceptible-exposed-infected-removed model of infectious disease spread. The delay was due to the time-lag from transmission to case reporting. We simulated the number of students infected daily with and without school closure and evaluated the effectiveness. Results The model with a 3-day delay from transmission to reporting yielded the best fit using R 2 (the coefficient of determination). This result suggests that the recommended period of school closure is more than 4 days. Moreover, the effect of school closure in the simulation of school closure showed the following: the number of infected students decreased by about 24% at its peak, and the number of cumulative infected students decreased by about 8.0%. Conclusions School closure was an effective intervention for mitigating the spread of influenza and should be implemented for more than 4 days. School closure has a remarkable impact on decreasing the number of infected students at the peak, but it does not substantially decrease the total number of infected students. PMID:26669757

Type of closure prevents microbial contamination of cosmetics during consumer use.

PubMed Central

Brannan, D K; Dille, J C

1990-01-01

The dispensing closure used for containers plays an important role in protecting cosmetics from in-use microbial contamination. This hypothesis was tested by aseptically packing unpreserved shampoo and skin lotion into containers with three different closure types which provided various degrees of protection against consumer and environmental microbial insults. Shampoo was packed in containers with slit-cap (n = 25), flip-cap (n = 25), or screw-cap (n = 28) closures. Skin lotion was packed in containers with pump-top (n = 21), flip-cap (n = 18), or screw-cap (n = 21) closures. The products were then used by volunteers under actual in-use conditions for 3 (shampoo) or 2 (skin lotion) weeks. After use, the products were evaluated for microbial contamination by using standard methods for enumeration and identification. The standard screw-cap closure provided only minimal protection against microbial contamination of both the shampoo (29% contamination incidence) and the skin lotion (71%). The slit-cap closure on the shampoo container and the flip-cap closure on the skin lotion container provided slightly enhanced degrees of protection (21 and 39% contamination incidence, respectively). The greatest amount of protection (i.e., lowest contamination incidence) was provided by the flip-cap closure for the shampoo container (0%) and the pump-top closure for the skin lotion container (10%). As a result, closure type plays an important role in protecting poorly preserved products from in-use microbial contamination. Images PMID:2339896

Reducing the risk of contamination of sterile parenteral products via ready-to-use closure components.

PubMed

Curry, Wayne; Conway, Samuel; Goodfield, Clara; Miller, Kimberly; Mueller, Ronald L; Polini, Eugene

2010-12-01

The preparation of sterile parenteral products requires careful control of all ingredients, materials, and processes to ensure the final product has the identity and strength, and meets the quality and purity characteristics that it purports to possess. Contamination affecting these critical properties of parenteral products can occur in many ways and from many sources. The use of closures supplied by manufacturers in a ready-to-use state can be an effective method for reducing the risk of contamination and improving the quality of the drug product. This article will address contamination attributable to elastomeric container closure components and the regulatory requirements associated with container closure systems. Possible contaminants, including microorganisms, endotoxins, and chemicals, along with the methods by which these contaminants can enter the product will be reviewed. Such methods include inappropriate material selection, improper closure preparation processes, compromised container closure integrity, degradation of closures, and leaching of compounds from the closures.

Application of continuous normal-lognormal bivariate density functions in a sensitivity analysis of municipal solid waste landfill.

PubMed

Petrovic, Igor; Hip, Ivan; Fredlund, Murray D

2016-09-01

The variability of untreated municipal solid waste (MSW) shear strength parameters, namely cohesion and shear friction angle, with respect to waste stability problems, is of primary concern due to the strong heterogeneity of MSW. A large number of municipal solid waste (MSW) shear strength parameters (friction angle and cohesion) were collected from published literature and analyzed. The basic statistical analysis has shown that the central tendency of both shear strength parameters fits reasonably well within the ranges of recommended values proposed by different authors. In addition, it was established that the correlation between shear friction angle and cohesion is not strong but it still remained significant. Through use of a distribution fitting method it was found that the shear friction angle could be adjusted to a normal probability density function while cohesion follows the log-normal density function. The continuous normal-lognormal bivariate density function was therefore selected as an adequate model to ascertain rational boundary values ("confidence interval") for MSW shear strength parameters. It was concluded that a curve with a 70% confidence level generates a "confidence interval" within the reasonable limits. With respect to the decomposition stage of the waste material, three different ranges of appropriate shear strength parameters were indicated. Defined parameters were then used as input parameters for an Alternative Point Estimated Method (APEM) stability analysis on a real case scenario of the Jakusevec landfill. The Jakusevec landfill is the disposal site of the capital of Croatia - Zagreb. The analysis shows that in the case of a dry landfill the most significant factor influencing the safety factor was the shear friction angle of old, decomposed waste material, while in the case of a landfill with significant leachate level the most significant factor influencing the safety factor was the cohesion of old, decomposed waste material. The analysis also showed that a satisfactory level of performance with a small probability of failure was produced for the standard practice design of waste landfills as well as an analysis scenario immediately after the landfill closure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gyre formation within embayments of a large lake (Lake Geneva, Switzerland)

NASA Astrophysics Data System (ADS)

Razmi, A.; Barry, D.; Bouffard, D.; Le Dantec, N.; Lemmin, U.; Wuest, A.

2013-12-01

Numerical simulations were carried out to examine gyre formation within open, wide lacustrine embayments. The present study was motivated by observed differences in gyre formation within two open and wide embayments (located at Vidy and Morges in Lake Geneva, Switzerland). These two embayments are located within about 3 km of each other on the northern shore of Lake Geneva, and are subjected to similar pelagic currents. Vidy is deeper and has a greater aspect ratio than Morges. The flow field in the embayments was modeled using a previously validated 3D hydrodynamic model (Delft3D-FLOW). The model solved the Reynolds-Averaged Navier-Stokes equations, combined with a k-ɛ turbulence closure in σ (lakebed-following) coordinates. Our study focused on the influence of the embayment geometry on the (uniform) longshore (pelagic) current, specifically the occurrence and magnitude of circulation within the embayment. We built a set of numerical experiments using synthetic embayments, and systematically examined embayment geometry, thereby capturing the differences between the Vidy and Morges embayments. The numerical experiments considered single rectilinear embayments with different aspect ratios (i.e., 1-6), depth, shore-parallel flow rates, and embayment corner angle between 0°-50°. The circulation magnitude changes abruptly for an angle of about 40°. Embayments with angles greater than 40° have much greater circulation then those with lesser angles, other factors remaining the same. Of the factors considered (i.e., aspect ratio, offshore current velocity, corner angle, bottom slope, and viscosity), bottom slope and the viscosity have almost no impact on embayment circulation. For uniform offshore current patterns, gyres form in embayments with large aspect ratios (up to ~3). For the Vidy and Morges embayments, the results showed that gyre formation is more likely in Morges due to its smaller aspect ratio, a finding that is supported by field data gathered in drifter studies. For example, simultaneous drifter releases in 2011 showed parallel-to-shore currents in the Vidy embayment and a gyre in Morges. KEYWORDS: Hydrodynamics; Open Embayment; Flow Separation; Gyre; Topography; Lake Geneva.

Prevalence of comorbid retinal disease in patients with glaucoma at an academic medical center.

PubMed

Griffith, Joseph F; Goldberg, Jeffrey L

2015-01-01

Patients with various retinal diseases and patients who have undergone retinal procedures and surgeries have an increased risk of developing ocular hypertension and glaucoma. Little is known about the epidemiology of comorbid retinal diseases in glaucoma patients. This study evaluated the prevalence of retinal comorbidities in a population of patients with five types of glaucoma. A longitudinal, retrospective study was conducted using International Classification of Disease (ICD-9) billing records from 2003 to 2010 at an academic medical center. Patients were classified as having primary open-angle glaucoma (POAG), low tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic-angle closure glaucoma (CACG), or pseudoexfoliation glaucoma (PXG) if they had at least three clinic visits with the same ICD-9 code. Patients were classified as having a retinal comorbidity if they had two visits with the same code. Variables were analyzed with the independent t-test, χ (2) test, analysis of variance, or Fisher's exact test. A total of 5,154 patients had glaucoma, and 14.8% of these had a retinal comorbidity. The prevalence of comorbid retinal disease was higher in patients with POAG (15.7%) than in those with NTG (10.7%), PXG (10.1%), or pigmentary open-angle glaucoma (3.7%; P<0.05). Two hundred and two patients had diabetic retinopathy, with POAG patients (4.5%) having a higher prevalence than those with CACG (1.4%) or PXG (0.6%; P<0.001). There were 297 patients who had macular degeneration and both POAG (2.0%) and PXG patients (2.9%) had a higher prevalence of nonexudative macular degeneration than those with CACG (0%; P<0.01). Patients with comorbid retinal disease had a higher prevalence of blindness and low vision than those without comorbid retinal disease (1.97% versus 1.02%, P=0.02). The high prevalence of comorbid retinal disease and the nearly twofold increase in blindness and low vision in this population demonstrate the need for ophthalmologists to determine if patients have multiple etiologies for their vision loss. The higher prevalence of certain retinal diseases in POAG patients may reflect common pathophysiological processes that warrant further investigation.

Modular low-aspect-ratio high-beta torsatron

DOEpatents

Sheffield, G.V.

1982-04-01

A fusion-reactor device is described which the toroidal magnetic field and at least a portion of the poloidal magnetic field are provided by a single set of modular coils. The coils are arranged on the surface of a low-aspect-ratio toroid in planed having the cylindrical coordinate relationship phi = phi/sub i/ + kz, where k is a constant equal to each coil's pitch and phi/sub i/ is the toroidal angle at which the i'th coil intersects the z = o plane. The toroid defined by the modular coils preferably has a race track minor cross section. When vertical field coils and, preferably, a toroidal plasma current are provided for magnetic-field-surface closure within the toroid, a vacuum magnetic field of racetrack-shaped minor cross section with improved stability and beta valves is obtained.

Burn Scar Near the Hanford Nuclear Reservation

NASA Technical Reports Server (NTRS)

2002-01-01

This Multi-angle Imaging Spectroradiometer (MISR) image pair shows 'before and after' views of the area around the Hanford Nuclear Reservation near Richland, Washington. On June 27, 2000, a fire in the dry sagebrush was sparked by an automobile crash. The flames were fanned by hot summer winds. By the day after the accident, about 100,000 acres had burned, and the fire's spread forced the closure of highways and loss of homes. These images were obtained by MISR's vertical-viewing (nadir) camera. Compare the area just above and to the right of the line of cumulus clouds in the May 15 image with the same area imaged on August 3. The darkened burn scar measures approximately 35 kilometers across. The Columbia River is seen wending its way around Hanford. Image courtesy NASA/GSFC/JPL, MISR Science Team

Research on driver fatigue detection

NASA Astrophysics Data System (ADS)

Zhang, Ting; Chen, Zhong; Ouyang, Chao

2018-03-01

Driver fatigue is one of the main causes of frequent traffic accidents. In this case, driver fatigue detection system has very important significance in avoiding traffic accidents. This paper presents a real-time method based on fusion of multiple facial features, including eye closure, yawn and head movement. The eye state is classified as being open or closed by a linear SVM classifier trained using HOG features of the detected eye. The mouth state is determined according to the width-height ratio of the mouth. The head movement is detected by head pitch angle calculated by facial landmark. The driver's fatigue state can be reasoned by the model trained by above features. According to experimental results, drive fatigue detection obtains an excellent performance. It indicates that the developed method is valuable for the application of avoiding traffic accidents caused by driver's fatigue.

Piezosurgery®-assisted periodontally accelerated osteogenic orthodontics.

PubMed

Pakhare, Vikas Vilas; Khandait, Chinmay Harishchandra; Shrivastav, Sunita Satish; Dhadse, Prasad Vijayrao; Baliga, Vidya Sudhindhra; Seegavadi, Vasudevan Dwarkanathan

2017-01-01

Periodontally accelerated osteogenic orthodontic procedure has become useful adjunct to reduce orthodontic treatment time as compared with conventional orthodontics. This case demonstrates the use of Piezosurgery ® to facilitate rapid tooth movement with relatively shorter treatment time. A 23-year-old male with Angles Class I malocclusion having spaced anterior teeth and protrusion requested orthodontic treatment with reduced time period. Before surgery, presurgical orthodontic treatment was done to do initial alignment of the teeth. This was followed by piezosurgical corticotomy and final space closure was achieved by active orthodontic tooth movement. The total treatment time required to complete the orthodontic treatment was 5 months. 1-year follow-up revealed no evidence of any adverse periodontal effects or relapse. Thus, Piezosurgery ® -assisted corticotomy may prove to be a noble and effective treatment approach to decrease the orthodontic treatment time.

Piezosurgery®-assisted periodontally accelerated osteogenic orthodontics

PubMed Central

Pakhare, Vikas Vilas; Khandait, Chinmay Harishchandra; Shrivastav, Sunita Satish; Dhadse, Prasad Vijayrao; Baliga, Vidya Sudhindhra; Seegavadi, Vasudevan Dwarkanathan

2017-01-01

Periodontally accelerated osteogenic orthodontic procedure has become useful adjunct to reduce orthodontic treatment time as compared with conventional orthodontics. This case demonstrates the use of Piezosurgery® to facilitate rapid tooth movement with relatively shorter treatment time. A 23-year-old male with Angles Class I malocclusion having spaced anterior teeth and protrusion requested orthodontic treatment with reduced time period. Before surgery, presurgical orthodontic treatment was done to do initial alignment of the teeth. This was followed by piezosurgical corticotomy and final space closure was achieved by active orthodontic tooth movement. The total treatment time required to complete the orthodontic treatment was 5 months. 1-year follow-up revealed no evidence of any adverse periodontal effects or relapse. Thus, Piezosurgery®-assisted corticotomy may prove to be a noble and effective treatment approach to decrease the orthodontic treatment time. PMID:29491592

Avoiding Accountability: How Charter Operators Evade Ohio's Automatic Closure Law. K-12 Education. Executive Summary

ERIC Educational Resources Information Center

DePaoli, Jennifer; van Lier, Piet

2013-01-01

Ohio's charter-closure law is touted as one of the toughest in the nation because it requires the automatic closure of charter schools that consistently fail to meet academic standards. Ohio's charter-closure law, which became effective in 2008 and was revised in 2011, calls for automatic closure of schools rated in Academic Emergency for at least…

Transcatheter closure of ventricular septal defect with Occlutech Duct Occluder.

PubMed

Atik-Ugan, Sezen; Saltik, Irfan Levent

2018-04-01

Patent ductus arteriosus occluders are used for transcatheter closure of ventricular septal defects, as well as for closure of patent ductus arteriosus. The Occlutech Duct Occluder is a newly introduced device for transcatheter closure of patent ductus arteriosus. Here, we present a case in which the Occlutech Duct Occluder was successfully used on a patient for the closure of a perimembraneous ventricular septal defect.

Transonic Investigation of Two-Dimensional Nozzles Designed for Supersonic Cruise

NASA Technical Reports Server (NTRS)

Capone, Francis J.; Deere, Karen A.

2015-01-01

An experimental and computational investigation has been conducted to determine the off-design uninstalled drag characteristics of a two-dimensional convergent-divergent nozzle designed for a supersonic cruise civil transport. The overall objectives were to: (1) determine the effects of nozzle external flap curvature and sidewall boattail variations on boattail drag; (2) develop an experimental data base for 2D nozzles with long divergent flaps and small boattail angles and (3) provide data for correlating computational fluid dynamic predictions of nozzle boattail drag. The experimental investigation was conducted in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0.80 to 1.20 at nozzle pressure ratios up to 9. Three-dimensional simulations of nozzle performance were obtained with the computational fluid dynamics code PAB3D using turbulence closure and nonlinear Reynolds stress modeling. The results of this investigation indicate that excellent correlation between experimental and predicted results was obtained for the nozzle with a moderate amount of boattail curvature. The nozzle with an external flap having a sharp shoulder (no curvature) had the lowest nozzle pressure drag. At a Mach number of 1.2, sidewall pressure drag doubled as sidewall boattail angle was increased from 4deg to 8deg. Reducing the height of the sidewall caused large decreases in both the sidewall and flap pressure drags. Summary

Epidemiology and clinical characteristics of patients with glaucoma: An analysis of hospital data between 2003 and 2012.

PubMed

Zhao, Yang; Fu, Jia-Li; Li, Yu-Li; Li, Ping; Lou, Feng-Lan

2015-11-01

To assess demographic and clinical characteristics of glaucoma patients in an Ophthalmologic Hospital of Jinan, China from 2003 to 2012. Medical charts of patients with primary open-angle glaucoma (POAG), primary angle closure glaucoma (PACG), and secondary glaucoma (SG) were reviewed. The main outcome measures of patients with glaucoma included basic demographic data (age at presentation, gender, and residence), clinical characteristics (admission date, intraocular pressure, and naked vision), and previous history (injury, cardiovascular disease, diabetes mellitus, hypertension, smoking, and alcohol consumption). Data from 1458 glaucoma patients were reviewed, of which PACG and SG patients accounted for 45.40% and 47.19%, respectively. The average age of all patients with glaucoma increased from 56.05 years in 2003 to 57.83 years in 2012, and the proportion of patients from rural areas rose from 46.43% to 59.13% during 10-year period. Female gender, cardiovascular disease, and hypertension were associated with PACG. POAG was related to smoking and alcohol consumption. There was positive correlation between SG and history of injury and diabetes mellitus. PACG and SG are the major types of glaucoma. Gender, injury, diabetes mellitus, cardiovascular disease, hypertension, smoking, and alcohol consumption were associated with different types of glaucoma.

The Chinese American Eye Study: Design and Methods

PubMed Central

Varma, Rohit; Hsu, Chunyi; Wang, Dandan; Torres, Mina; Azen, Stanley P.

2016-01-01

Purpose To summarize the study design, operational strategies and procedures of the Chinese American Eye Study (CHES), a population-based assessment of the prevalence of visual impairment, ocular disease, and visual functioning in Chinese Americans. Methods This population-based, cross-sectional study, included 4,570 Chinese, 50 years and older, residing in the city of Monterey Park, California. Each eligible participant completed a detailed interview and eye examination. The interview included an assessment of demographic, behavioral, and ocular risk factors and health-related and vision-related quality of life. The eye examination included measurements of visual acuity, intraocular pressure, visual fields, fundus and optic disc photography, a detailed anterior and posterior segment examination, and measurements of blood pressure, glycosylated hemoglobin levels, and blood glucose levels. Results The objectives of the CHES are to obtain prevalence estimates of visual impairment, refractive error, diabetic retinopathy, open-angle and angle-closure glaucoma, lens opacities, and age-related macular degeneration in Chinese-Americans. In addition, outcomes include effect estimates for risk factors associated with eye diseases. Lastly, CHES will investigate the genetic determinates of myopia and glaucoma. Conclusion The CHES will provide information about the prevalence and risk factors of ocular diseases in one of the fastest growing minority groups in the United States. PMID:24044409

Model-Based Comprehensive Analysis of School Closure Policies for Mitigating Influenza Epidemics and Pandemics

PubMed Central

Fumanelli, Laura; Ajelli, Marco; Merler, Stefano; Ferguson, Neil M.; Cauchemez, Simon

2016-01-01

School closure policies are among the non-pharmaceutical measures taken into consideration to mitigate influenza epidemics and pandemics spread. However, a systematic review of the effectiveness of alternative closure policies has yet to emerge. Here we perform a model-based analysis of four types of school closure, ranging from the nationwide closure of all schools at the same time to reactive gradual closure, starting from class-by-class, then grades and finally the whole school. We consider policies based on triggers that are feasible to monitor, such as school absenteeism and national ILI surveillance system. We found that, under specific constraints on the average number of weeks lost per student, reactive school-by-school, gradual, and county-wide closure give comparable outcomes in terms of optimal infection attack rate reduction, peak incidence reduction or peak delay. Optimal implementations generally require short closures of one week each; this duration is long enough to break the transmission chain without leading to unnecessarily long periods of class interruption. Moreover, we found that gradual and county closures may be slightly more easily applicable in practice as they are less sensitive to the value of the excess absenteeism threshold triggering the start of the intervention. These findings suggest that policy makers could consider school closure policies more diffusely as response strategy to influenza epidemics and pandemics, and the fact that some countries already have some experience of gradual or regional closures for seasonal influenza outbreaks demonstrates that logistic and feasibility challenges of school closure strategies can be to some extent overcome. PMID:26796333

Model-Based Comprehensive Analysis of School Closure Policies for Mitigating Influenza Epidemics and Pandemics.

PubMed

Fumanelli, Laura; Ajelli, Marco; Merler, Stefano; Ferguson, Neil M; Cauchemez, Simon

2016-01-01

School closure policies are among the non-pharmaceutical measures taken into consideration to mitigate influenza epidemics and pandemics spread. However, a systematic review of the effectiveness of alternative closure policies has yet to emerge. Here we perform a model-based analysis of four types of school closure, ranging from the nationwide closure of all schools at the same time to reactive gradual closure, starting from class-by-class, then grades and finally the whole school. We consider policies based on triggers that are feasible to monitor, such as school absenteeism and national ILI surveillance system. We found that, under specific constraints on the average number of weeks lost per student, reactive school-by-school, gradual, and county-wide closure give comparable outcomes in terms of optimal infection attack rate reduction, peak incidence reduction or peak delay. Optimal implementations generally require short closures of one week each; this duration is long enough to break the transmission chain without leading to unnecessarily long periods of class interruption. Moreover, we found that gradual and county closures may be slightly more easily applicable in practice as they are less sensitive to the value of the excess absenteeism threshold triggering the start of the intervention. These findings suggest that policy makers could consider school closure policies more diffusely as response strategy to influenza epidemics and pandemics, and the fact that some countries already have some experience of gradual or regional closures for seasonal influenza outbreaks demonstrates that logistic and feasibility challenges of school closure strategies can be to some extent overcome.

3718-F Alkali Metal Treatment and Storage Facility Closure Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Since 1987, Westinghouse Hanford Company has been a major contractor to the U.S. Department of Energy-Richland Operations Office and has served as co-operator of the 3718-F Alkali Metal Treatment and Storage Facility, the waste management unit addressed in this closure plan. The closure plan consists of a Part A Dangerous waste Permit Application and a RCRA Closure Plan. An explanation of the Part A Revision (Revision 1) submitted with this document is provided at the beginning of the Part A section. The closure plan consists of 9 chapters and 5 appendices. The chapters cover: introduction; facility description; process information; wastemore » characteristics; groundwater; closure strategy and performance standards; closure activities; postclosure; and references.« less

Closure of hazardous and mixed radioactive waste management units at DOE facilities. [Contains glossary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This is document addresses the Federal regulations governing the closure of hazardous and mixed waste units subject to Resource Conservation and Recovery Act (RCRA) requirements. It provides a brief overview of the RCRA permitting program and the extensive RCRA facility design and operating standards. It provides detailed guidance on the procedural requirements for closure and post-closure care of hazardous and mixed waste management units, including guidance on the preparation of closure and post-closure plans that must be submitted with facility permit applications. This document also provides guidance on technical activities that must be conducted both during and after closure ofmore » each of the following hazardous waste management units regulated under RCRA.« less

A novel one-shot circular stapler closure for atrial septal defect in a beating-heart porcine model.

PubMed

Tarui, Tatsuya; Tomita, Shigeyuki; Ishikawa, Norihiko; Ohtake, Hiroshi; Watanabe, Go

2015-02-01

In surgical atrial septal defect (ASD) closure, there are no techniques or devices that can close the ASD accurately in a short time under a beating heart. We have developed a simple and automatic ASD closure technique using a circular stapler. This study assessed the feasibility and efficacy of a new circular stapler closure for ASD. Under a continuous beating heart, hand-sewn patch plasty ASD closure was performed in 6 pigs (group A) and circular stapler ASD closure was performed in 6 pigs (group B). The time to close the ASD and the effectiveness of the closure were compared. Closure was significantly faster in group B (10.5 ± 1.0 seconds) than in group A (664 ± 10 seconds; p < 0.05). There was no leakage at the closure site, and sufficient tolerance was confirmed. A circular stapler can be used to treat ASD faster than hand-sewn patch plasty, with sufficient pressure tolerance in a beating heart porcine model. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

CFD Simulation of Turbulent Wind Effect on an Array of Ground-Mounted Solar PV Panels

NASA Astrophysics Data System (ADS)

Irtaza, Hassan; Agarwal, Ashish

2018-06-01

Aim of the present study is to determine the wind loads on the PV panels in a solar array since panels are vulnerable to high winds. Extensive damages of PV panels, arrays and mounting modules have been reported the world over due to high winds. Solar array of dimension 6 m × 4 m having 12 PV panels of size 1 m × 2 m on 3D 1:50 scaled models have been simulated using unsteady solver with Reynolds-Averaged Navier-Stokes equations of computational fluid dynamics techniques to study the turbulent wind effects on PV panels. A standalone solar array with 30° tilt angle in atmospheric surface layer with the Renormalized Group (RNG) turbulence closure subjected to incident wind varied from - 90° to 90°. The net pressure, drag and lift coefficients are found to be maximum when the wind is flowing normally to the PV panel either 90° or - 90°. The tilt angle of solar arrays the world over not vary on the latitude but also on the seasons. Keeping this in mind the ground mounted PV panels in array with varying tilt angle from 10° to 60° at an interval of 10° have been analyzed for normal wind incident i.e. 90° and - 90° using unsteady RNG turbulence model. Net pressure coefficients have been calculated and found to be increasing with increase in array tilting angle. Maximum net pressure coefficient was observed for the 60° tilted PV array for 90° and - 90° wind incident having value of 0.938 and 0.904 respectively. The results can be concluded that the PV panels are subjected to significant lift and drag forces under wind loading, which needs to be quantified with sufficient factor of safety to avoid damages.

CFD Simulation of Turbulent Wind Effect on an Array of Ground-Mounted Solar PV Panels

NASA Astrophysics Data System (ADS)

Irtaza, Hassan; Agarwal, Ashish

2018-02-01

Aim of the present study is to determine the wind loads on the PV panels in a solar array since panels are vulnerable to high winds. Extensive damages of PV panels, arrays and mounting modules have been reported the world over due to high winds. Solar array of dimension 6 m × 4 m having 12 PV panels of size 1 m × 2 m on 3D 1:50 scaled models have been simulated using unsteady solver with Reynolds-Averaged Navier-Stokes equations of computational fluid dynamics techniques to study the turbulent wind effects on PV panels. A standalone solar array with 30° tilt angle in atmospheric surface layer with the Renormalized Group (RNG) turbulence closure subjected to incident wind varied from - 90° to 90°. The net pressure, drag and lift coefficients are found to be maximum when the wind is flowing normally to the PV panel either 90° or - 90°. The tilt angle of solar arrays the world over not vary on the latitude but also on the seasons. Keeping this in mind the ground mounted PV panels in array with varying tilt angle from 10° to 60° at an interval of 10° have been analyzed for normal wind incident i.e. 90° and - 90° using unsteady RNG turbulence model. Net pressure coefficients have been calculated and found to be increasing with increase in array tilting angle. Maximum net pressure coefficient was observed for the 60° tilted PV array for 90° and - 90° wind incident having value of 0.938 and 0.904 respectively. The results can be concluded that the PV panels are subjected to significant lift and drag forces under wind loading, which needs to be quantified with sufficient factor of safety to avoid damages.

75 FR 21039 - Notice of Temporary Road Closure of Coal Pit Spring-Cave Gulch Road (6287-0-B0), Within the Cave...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-22

... stabilization. The BLM posted signs at main entry points to the temporary closure area. Maps of the closed roads...; HAG10-0046] Notice of Temporary Road Closure of Coal Pit Spring--Cave Gulch Road (6287-0-B0), Within the... closure. SUMMARY: Notice is hereby given that a temporary road closure to public access, use, or occupancy...

100-D Ponds closure plan. Revision 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petersen, S.W.

1997-09-01

The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit ismore » clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean closure.« less

Assessment of a simple, novel endoluminal method for gastrotomy closure in NOTES.

PubMed

Lee, Sang Soo; Oelschlager, Brant K; Wright, Andrew S; Soares, Renato V; Sinan, Huseyin; Montenovo, Martin I; Hwang, Joo Ha

2011-10-01

A reliable method for gastrotomy closure in NOTES will be essential for NOTES to become viable clinically. However, methods using existing and widely available endoscopic accessories have been ineffective. The objective of this study was to evaluate the feasibility and safety of a new simple method for gastric closure (retracted clip-assisted loop closure) that uses existing endoscopic accessories with minor modifications. The retracted clip-assisted loop closure technique involves deploying 3-4 Resolution(®) clips (modified by attaching a 90-cm length of suture to the end of each clip) along the margin of the gastrotomy with one jaw on the serosal surface and the other jaw on the mucosal surface. The suture strings are threaded through an endoloop. Traction is then applied to the strings causing the gastric wall to tent. The endoloop is secured below the tip of the clips, completing a full-thickness gastrotomy closure. The main outcome measures were feasibility, efficacy, and safety of the new retracted clip-assisted loop closure technique for NOTES gastrotomy closure. An air-tight seal was achieved in 100% (n = 9) of stomachs. The mean leak pressure was 116.3 (±19.4) mmHg. The retracted clip-assisted loop closure technique can be used to perform NOTES gastrotomy closure by using existing endoscopic accessories with minor modifications.

Transcatheter closure of patent ductus arteriosus: past, present and future.

PubMed

Baruteau, Alban-Elouen; Hascoët, Sébastien; Baruteau, Julien; Boudjemline, Younes; Lambert, Virginie; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme; Pass, Robert

2014-02-01

This review aims to describe the past history, present techniques and future directions in transcatheter treatment of patent ductus arteriosus (PDA). Transcatheter PDA closure is the standard of care in most cases and PDA closure is indicated in any patient with signs of left ventricular volume overload due to a ductus. In cases of left-to-right PDA with severe pulmonary arterial hypertension, closure may be performed under specific conditions. The management of clinically silent or very tiny PDAs remains highly controversial. Techniques have evolved and the transcatheter approach to PDA closure is now feasible and safe with current devices. Coils and the Amplatzer Duct Occluder are used most frequently for PDA closure worldwide, with a high occlusion rate and few complications. Transcatheter PDA closure in preterm or low-bodyweight infants remains a highly challenging procedure and further device and catheter design development is indicated before transcatheter closure is the treatment of choice in this delicate patient population. The evolution of transcatheter PDA closure from just 40 years ago with 18F sheaths to device delivery via a 3F sheath is remarkable and it is anticipated that further improvements will result in better safety and efficacy of transcatheter PDA closure techniques. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Percutaneous closure of patent ductus arteriosus in children: Immediate and short-term changes in left ventricular systolic and diastolic function.

PubMed

Gupta, Saurabh Kumar; Krishnamoorthy, Km; Tharakan, Jaganmohan A; Sivasankaran, S; Sanjay, G; Bijulal, S; Anees, T

2011-07-01

To evaluate the effect of percutaneous closure of patent ductus arteriosus (PDA) on left ventricular (LV) systolic and diastolic function in children. Limited studies are available on alteration in LV hemodynamics, especially diastolic function, after PDA closure. Thirty-two consecutive children with isolated PDA treated by trans-catheter closure were studied. The LV systolic and diastolic function were assessed by two-dimensional (2D) echocardiography and tissue Doppler imaging 1 day before the PDA closure, on day 1, and on follow-up. At baseline, none of the patients had LV systolic dysfunction. On day 1 post-PDA closure, 8 (25%) children developed LV systolic dysfunction. The baseline LV ejection fraction (LVEF), LV end-systolic dimension (LVESD), and PDA diastolic gradient predicted the post-closure LVEF. Patients who developed post-closure LV systolic dysfunction had poorer LV diastolic function than those who did not. LV diastolic properties improved after PDA closure; however, the improvement in LV diastolic properties lagged behind the improvement in the LV systolic function. All children were asymptomatic and had normal LVEF on follow up of >3 months. Percutaneous closure of PDA is associated with the reversible LV systolic dysfunction. Improvement in the LV diastolic function lags behind that in the LV systolic function.

Autologous transplantation of the internal limiting membrane for refractory macular holes.

PubMed

Morizane, Yuki; Shiraga, Fumio; Kimura, Shuhei; Hosokawa, Mio; Shiode, Yusuke; Kawata, Tetsuhiro; Hosogi, Mika; Shirakata, Yukari; Okanouchi, Toshio

2014-04-01

To determine the effectiveness of autologous transplantation of the internal limiting membrane (ILM) for refractory macular holes. Prospective, interventional case series. Ten eyes of 10 consecutive patients who underwent autologous transplantation of the ILM for the treatment of refractory macular holes were studied. The primary diseases in these patients were large idiopathic macular holes that had existed for more than 1 year (4 eyes), a traumatic macular hole (1 eye), myopic foveoschisis (2 eyes), foveoschisis resulting from pit-macular syndrome (2 eyes), and proliferative diabetic retinopathy (1 eye). Apart from the 5 eyes with idiopathic or traumatic macular holes, macular holes developed in the other 5 eyes after initial vitrectomies with ILM removal. In all eyes, regular macular hole surgery failed to achieve closure. The main outcome measures used in this study were macular hole closure and best-corrected visual acuity (BCVA). Macular holes were closed successfully in 9 eyes (90%) after autologous transplantation of the ILM. The postoperative BCVAs were significantly better than the preoperative BCVAs (P = .007, paired t test). Postoperative BCVAs improved by more than 0.2 logarithm of the minimal angle of resolution units in 8 eyes (80%) and were unchanged in 2 eyes (20%). Although this is a pilot study, the results suggest that autologous transplantation of the ILM may contribute to improved anatomic and visual outcomes in the treatment of refractory macular holes and may warrant further investigation. Copyright © 2014 Elsevier Inc. All rights reserved.

A meta-analysis of vitrectomy with or without internal limiting membrane peeling for macular hole retinal detachment in the highly myopic eyes.

PubMed

Gao, Xinxiao; Guo, Jia; Meng, Xin; Wang, Jun; Peng, Xiaoyan; Ikuno, Yasushi

2016-06-13

To evaluate the anatomical and visual outcomes by par plana vitrectomy with or without internal limiting membrane (ILM) peeling in highly myopic eyes with macular hole retinal detachment (MHRD). MEDLINE (Ovid, PubMed) and EMBASE were used for data collection up to September 30, 2015. The parameters of anatomical success, macular hole closure and improved best corrected visual acuity (BCVA) at or beyond 6 months after operation were assessed as the primary outcome measurement. The meta-analysis was performed with the fixed-effects model. Seven comparative analyses involving a total of 373 patients were included in the present meta-analysis. Statistically the pooled data showed significant relative risk (RR) in terms of primary reattachment between ILM peeling and non-peeling groups (RR, 1.19; 95 % CI, 1.04 to 1.36; P = 0.012). An effect favoring ILM peeling with regard to macular hole closure was also detected (RR, 1.71; 95 % CI, 1.20 to 2.43; P = 0.003). However, no statistically significant difference was found in the improved BCVA (logarithm of the minimum angle of resolution) at 6 months or more (95 % CI, -0.31 to 0.44; P = 0.738). There is no proved benefit of postoperative visual improvement. However, the available evidences from this study suggested a superiority of ILM peeling over no peeling for myopic patients with MHRD.

The open abdomen and temporary abdominal closure systems--historical evolution and systematic review.

PubMed

Quyn, A J; Johnston, C; Hall, D; Chambers, A; Arapova, N; Ogston, S; Amin, A I

2012-08-01

Several techniques for temporary abdominal closure have been developed. We systematically review the literature on temporary abdominal closure to ascertain whether the method can be tailored to the indication. Medline, Embase, the Cochrane Central Register of Controlled Trials and relevant meeting abstracts until December 2009 were searched using the following headings: open abdomen, laparostomy, VAC (vacuum assisted closure), TNP (topical negative pressure), fascial closure, temporary abdominal closure, fascial dehiscence and deep wound dehiscence. The data were analysed by closure technique and aetiology. The primary end-points included delayed fascial closure and in-hospital mortality. The secondary end-points were intra-abdominal complications. The search identified 106 papers for inclusion. The techniques described were VAC (38 series), mesh/sheet (30 series), packing (15 series), Wittmann patch (eight series), Bogotá bag (six series), dynamic retention sutures (three series), zipper (15 series), skin only and locking device (one series each). The highest facial closure rates were seen with the Wittmann patch (78%), dynamic retention sutures (71%) and VAC (61%). Temporary abdominal closure has evolved from simple packing to VAC based systems. In the absence of sepsis Wittmann patch and VAC offered the best outcome. In its presence VAC had the highest delayed primary closure and the lowest mortality rates. However, due to data heterogeneity only limited conclusions can be drawn from this analysis. © 2012 The Authors. Colorectal Disease © 2012 The Association of Coloproctology of Great Britain and Ireland.

Randomized clinical trial of intestinal ostomy takedown comparing pursestring wound closure vs conventional closure to eliminate the risk of wound infection.

PubMed

Camacho-Mauries, Daniel; Rodriguez-Díaz, José Luis; Salgado-Nesme, Noel; González, Quintín H; Vergara-Fernández, Omar

2013-02-01

The use of temporary stomas has been demonstrated to reduce septic complications, especially in high-risk anastomosis; therefore, it is necessary to reduce the number of complications secondary to ostomy takedowns, namely wound infection, anastomotic leaks, and intestinal obstruction. To compare the rates of superficial wound infection and patient satisfaction after pursestring closure of ostomy wound vs conventional linear closure. Patients undergoing colostomy or ileostomy closure between January 2010 and February 2011 were randomly assigned to linear closure (n = 30) or pursestring closure (n = 31) of their ostomy wound. Wound infection within 30 days of surgery was defined as the presence of purulent discharge, pain, erythema, warmth, or positive culture for bacteria. Patient satisfaction, healing time, difficulty managing the wound, and limitation of activities were analyzed with the Likert questionnaire. The infection rate for the control group was 36.6% (n = 11) vs 0% in the pursestring closure group (p < 0.0001). Healing time was 5.9 weeks in the linear closure group and 3.8 weeks in the pursestring group (p = 0.0002). Seventy percent of the patients with pursestring closure were very satisfied in comparison with 20% in the other group (p = 0.0001). This study was limited by the heterogeneity in the type of stoma in both groups. The pursestring method resulted in the absence of infection after ostomy wound closure (shorter healing time and improved patient satisfaction).

32 CFR 989.25 - Base closure and realignment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure... frequently contain provisions limiting the extent of environmental analysis required for actions taken under...

32 CFR 989.25 - Base closure and realignment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure... frequently contain provisions limiting the extent of environmental analysis required for actions taken under...

Closure of colostomy.

PubMed Central

Beck, P H; Conklin, H B

1975-01-01

We analyzed the records of 77 cases of loop colostomy closure in Vietnam War Casualties. All records were complete from the date of injury to discharge following colostomy closure. Simple of the loop colostomy was performed in 44 patients and resection of the stoma and reanastomosis of bowel segments was performed in 33 patients. Average operating time for simple closure of the loop was 70 minutes compared to 115 minutes for resection and anastomosis. Nasogastric suction was used less frequently and for a shorter time with simple loop closure. The total postoperative complication rate was 9% with simple loop closure as compared to 24% for resection and anastomosis. Simple closure of the loop described in this report is technically easier and as safe as resection of the stoma and reanastomosis. Images Fig. 1. PMID:1094967

Silicone absorption of elastomeric closures--an accelerated study.

PubMed

Degrazio, F L; Hlobik, T; Vaughan, S

1998-01-01

There is a trend in the parenteral industry to move from the use of elastomeric closures which are washed, siliconized, dried and sterilized in-house at the pharmaceutical manufacturers' site to pre-prepared closures purchased from the closure supplier. This preparation can consist of washing to reduce particle-load and bioburden, siliconization, placement in ready-to-sterilize bags and may eventually extend to sterilization by steam autoclave or gamma irradiation. Since silicone oil lubrication is critical to the processability/machinability of closures, research was designed to investigate this phenomenon in closures prepared using the Westar RS (Ready-to-Sterilize) process. This paper presents the data gathered in a study of the characteristic of silicone absorption into elastomeric closures under accelerated conditions. Variables such as silicone viscosity, rubber formulation, effect of sterilization and others are considered.

Influence of glottal closure configuration on vocal efficacy in young normal-speaking women.

PubMed

Schneider, Berit; Bigenzahn, Wolfgang

2003-12-01

Posterior closure insufficiency of the glottis is often mentioned in connection with permanent voice disorders. Recently published studies have revealed that an incomplete closure of the glottis can be found also in normal-speaking voices, especially in women. However, the effect of glottal closure configuration on vocal efficacy is not sufficiently clarified. The purpose of this study was to determine the effect of glottal closure configuration on singing and speaking voice characteristics. Overall, 520 young female normal-speaking subjects were examined by videostroboscopy for different phonation conditions in the combination of soft, loud, low, and/or high phonation and by voice range profile measurements. According to the videostroboscopic analysis, the subjects were subdivided into four groups: complete closure of the vocal folds already in soft phonation (group 1), closure of the vocal fold with increasing intensity (group 2), persistent closure insufficiencies despite increasing intensity (group 3), and hourglass-shaped closure in subjects with vocal nodules (group 4). Subjects in which the glottal closure could not be evaluated sufficiently were subclassified into group 5 (missing values). Selected criteria of the singing and speaking voice were evaluated and statistically processed according to the mentioned subclassification. Group 1 reached significantly the highest sound pressure levels (SPLmax) for the singing voice as well as for the shouting voice. Group 3 showed a limited capacity to increase the intensity of the singing and speaking voice. The results gathered in this study objectify the relationship of insufficient glottal closure and reduced vocal capabilities. As long as no conclusive data on long-term consequences of insufficient glottal closure are available, a prophylactic improvement of the laryngeal situation especially in female professional voice users by voice therapy should be recommended.

Endoscopic closure of duodenal perforations by using an over-the-scope clip: a randomized, controlled porcine study.

PubMed

von Renteln, Daniel; Rudolph, Hans-Ulrich; Schmidt, Arthur; Vassiliou, Melina C; Caca, Karel

2010-01-01

Duodenal perforations during diagnostic upper endoscopy are rare; however, when therapeutic techniques are performed, the reported incidence is as great as 2.8%. Surgical repair is usually mandated, but it is associated with significant morbidity and mortality. To compare closure of duodenal perforations by using an over-the-scope clip (OTSC) with a surgical closure. Randomized, controlled animal study. Animal facility laboratory. Domestic pigs (24 females). Large (10-mm) duodenal perforations were created by using an endoscopic needle-knife. The animals were randomly assigned to either open surgical repair (n=12) or endoscopic closure by using the OTSC system (n=12). Pressurized leak tests were performed during necropsy. One major bleed occurred because of a liver injury during creation of the duodenotomy. Mean time for endoscopic closure was 5 minutes (range, 3-8 min; SD +/- 2). No complications occurred during any of the closure procedures. At necropsy, all OTSC and surgical closures demonstrated complete sealing of duodenotomy sites. Pressurized leak tests demonstrated a mean burst pressure of 166 mm Hg (range, 80-260; SD +/- 65) for OTSC closures and 143 mm Hg (range, 30-300, SD +/- 83) for surgical sutures. Ex vivo intact duodenal specimens exhibited a mean burst pressure of 247 mm Hg (range, 200-300; SD +/- 35), which was significantly higher compared with in vivo OTSC and surgical closures (P < .01). There were no significant differences between burst pressures of OTSC and surgical closures (P = .461). Nonsurvival setting. Endoscopic closure of duodenal perforations by using the OTSC system is comparable with surgical closure in a nonsurvival porcine model. This technique is easy to perform and seems suitable for repairing duodenal perforations. 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

School closure as an influenza mitigation strategy: how variations in legal authority and plan criteria can alter the impact.

PubMed

Potter, Margaret A; Brown, Shawn T; Cooley, Phillip C; Sweeney, Patricia M; Hershey, Tina B; Gleason, Sherrianne M; Lee, Bruce Y; Keane, Christopher R; Grefenstette, John; Burke, Donald S

2012-11-14

States' pandemic influenza plans and school closure statutes are intended to guide state and local officials, but most faced a great deal of uncertainty during the 2009 influenza H1N1 epidemic. Questions remained about whether, when, and for how long to close schools and about which agencies and officials had legal authority over school closures. This study began with analysis of states' school-closure statutes and pandemic influenza plans to identify the variations among them. An agent-based model of one state was used to represent as constants a population's demographics, commuting patterns, work and school attendance, and community mixing patterns while repeated simulations explored the effects of variations in school closure authority, duration, closure thresholds, and reopening criteria. The results show no basis on which to justify statewide rather than school-specific or community-specific authority for school closures. Nor do these simulations offer evidence to require school closures promptly at the earliest stage of an epidemic. More important are criteria based on monitoring of local case incidence and on authority to sustain closure periods sufficiently to achieve epidemic mitigation. This agent-based simulation suggests several ways to improve statutes and influenza plans. First, school closure should remain available to state and local authorities as an influenza mitigation strategy. Second, influenza plans need not necessarily specify the threshold for school closures but should clearly define provisions for early and ongoing local monitoring. Finally, school closure authority may be exercised at the statewide or local level, so long as decisions are informed by monitoring incidence in local communities and schools.

Surgical impact and speech outcome at 2.5 years after one- or two-stage cleft palate closure.

PubMed

Randag, Anna C; Dreise, Marieke M; Ruettermann, Mike

2014-11-01

In the ongoing discussion about timing of palate closure, it is said that early closure is favorable for speech development, but can interfere with maxillary growth. On the other hand, beneficial results on both after one-stage palate closure have also been presented. The assumption that one-stage palate closure leads to less surgical impact on the child probably contributed to the choice for this procedure in most cleft centers. However, no previous research has verified this assumption. The aim of the present study is to compare surgical impact and speech outcome at 2.5 years of age between children who underwent either one- or early two-stage palate closure. Patients underwent either one-stage palate closure between 2007 and 2010 at a median age of 10.8 months (group 1, n=24) or early two-stage closure before 2007 at median ages of 10.4 and 18.2 months, respectively (group 2, n=24). Surgical impact was compared between the two groups by means of duration of surgery, length of hospital stay and number of post-operative complications. Speech outcome was compared by means of resonance problems, nasal air emission, articulation and intelligibility, all assessed at a median age of 2.5 years. The one-stage closure group showed significantly shorter duration of surgery and length of hospital stay (p<0.001 and p=0.001, respectively) and significantly better articulation (p=0.029) than the early two-stage closure group. One-stage palate closure is preferable over early two-stage palate closure with regard to surgical impact and speech development. More extensive, prospective studies, in which maxillary growth is taken into account, should be conducted. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

No evidence that manual closure of the bronchial stump has a lower failure rate than mechanical stapler closure following anatomical lung resection.

PubMed

Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian

2014-04-01

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5-12.5%) than in patients who underwent mechanical closure (1-5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection.

40 CFR 264.197 - Closure and post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Section 264.197 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES... as hazardous waste, unless § 261.3(d) of this chapter applies. The closure plan, closure activities...

Catheter-based closure of the patent ductus arteriosus in lower weight infants.

PubMed

Pavlek, Leeann R; Slaughter, Jonathan L; Berman, Darren P; Backes, Carl H

2018-06-13

Risks associated with drug therapy and surgical ligation have led health care providers to consider alternative strategies for patent ductus arteriosus (PDA) closure. Catheter-based PDA closure is the procedure of choice for ductal closure in adults, children, and infants ≥6kg. Given evidence among older counterparts, interest in catheter-based closure of the PDA in lower weight (<6kg) infants is growing. Among these smaller infants, the goals of this review are to: (1) provide an overview of the procedure; (2) review the types of PDA closure devices; (3) review the technical success (feasibility); (4) review the risks (safety profile); (5) discuss the quality of evidence on procedural efficacy; (6) consider areas for future research. The review provided herein suggests that catheter-based PDA closure is technically feasible, but the lack of comparative trials precludes determination of the optimal strategy for ductal closure in this subgroup of infants. Copyright © 2018 Elsevier Inc. All rights reserved.

Prognostic significance of pleural lavage cytology after thoracotomy and before closure of the chest in lung cancer.

PubMed

Taniguchi, Yuji; Nakamura, Hiroshige; Miwa, Ken; Adachi, Yoshin; Fujioka, Shinji; Haruki, Tomohiro; Horie, Yasushi

2009-07-01

Some reports have described pleural lavage cytology (PLC) to be a prognostic factor for non-small cell lung cancer (NSCLC) patients. However, there have only been a few reports describing the findings both immediately after thoracotomy (PLC after thoracotomy) and before the closure of the chest (PLC before closure). From April 2002 to April 2008, both PLC after thoracotomy and PLC before closure were performed in 296 consecutive patients who underwent resections for NSCLC. PLC after thoracotomy was positive in 14 patients. The survival rate in the PLC after thoracotomy positive cases was significantly poorer than in PLC after thoracotomy negative cases (P=0.047). In contrast, there were 26 PLC before closure positive cases. The survival rate in the PLC before closure positive cases was significantly poorer than in the PLC before closure negative cases (P<0.0001). Multivariate analyses revealed that PLC after thoracotomy is not an independent prognostic factor in our study. However, PLC before closure was an independent prognostic factor based on multivariate analyses. We conclude that PLC before closure was found to be a better prognostic factor than PLC after thoracotomy for NSCLC patients.

Final closure plan for the high-explosives open burn treatment facility at Lawrence Livermore National Laboratory Experimental Test Site 300

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathews, S.

This document addresses the interim status closure of the HE Open Bum Treatment Facility, as detailed by Title 22, Division 4.5, Chapter 15, Article 7 of the Califonia Code of Regulations (CCR) and by Title 40, Code of Federal Regulations (CFR) Part 265, Subpart G, ``Closure and Post Closure.`` The Closure Plan (Chapter 1) and the Post- Closure Plan (Chapter 2) address the concept of long-term hazard elimination. The Closure Plan provides for capping and grading the HE Open Bum Treatment Facility and revegetating the immediate area in accordance with applicable requirements. The Closure Plan also reflects careful consideration ofmore » site location and topography, geologic and hydrologic factors, climate, cover characteristics, type and amount of wastes, and the potential for contaminant migration. The Post-Closure Plan is designed to allow LLNL to monitor the movement, if any, of pollutants from the treatment area. In addition, quarterly inspections will ensure that all surfaces of the closed facility, including the cover and diversion ditches, remain in good repair, thus precluding the potential for contaminant migration.« less

Improvement of tricuspid regurgitation after transcatheter ASD closure in older patients.

PubMed

Chen, L; Shen, J; Shan, X; Wang, F; Kan, T; Tang, X; Zhao, X; Qin, Y

2017-07-19

Adult patients with undiagnosed atrial septal defect (ASD) may have right heart cavity enlargement and functional tricuspid valve insufficiency. Moderate or more severe tricuspid regurgitation has been associated with a worse prognosis, and more serious complications are typically seen in older patients. This study aimed to evaluate the improvement in functional tricuspid regurgitation and heart geometry after transcatheter ASD closure in older patients. The data of 111 patients over 60 years of age with moderate or severe tricuspid regurgitation before ASD closure were analyzed. At the 1‑month and 6‑month follow-up after closure, both tricuspid regurgitation jet area and right atrial volume decreased significantly. Right ventricular volume decreased 1 month after closure, showing a further decrease at the end of the 6‑month follow-up. However, 24 patients (21.6%) still had persistent severe tricuspid regurgitation after the procedure. Multivariate analysis revealed that patient age at ASD closure and pulmonary artery systolic pressure determined by echocardiography before closure were predictors of persistent tricuspid regurgitation after closure. Transcatheter ASD closure in older patients could significantly decrease tricuspid regurgitation and improve right heart geometry.

10 CFR 61.29 - Post-closure observation and maintenance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Post-closure observation and maintenance. 61.29 Section 61.29 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Licenses § 61.29 Post-closure observation and maintenance. Following completion of closure...

10 CFR 61.29 - Post-closure observation and maintenance.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Post-closure observation and maintenance. 61.29 Section 61.29 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Licenses § 61.29 Post-closure observation and maintenance. Following completion of closure...

10 CFR 61.29 - Post-closure observation and maintenance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Post-closure observation and maintenance. 61.29 Section 61.29 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Licenses § 61.29 Post-closure observation and maintenance. Following completion of closure...

10 CFR 61.29 - Post-closure observation and maintenance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Post-closure observation and maintenance. 61.29 Section 61.29 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Licenses § 61.29 Post-closure observation and maintenance. Following completion of closure...

10 CFR 61.29 - Post-closure observation and maintenance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Post-closure observation and maintenance. 61.29 Section 61.29 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Licenses § 61.29 Post-closure observation and maintenance. Following completion of closure...

Simulating school closure policies for cost effective pandemic decision making

PubMed Central

2012-01-01

Background Around the globe, school closures were used sporadically to mitigate the 2009 H1N1 influenza pandemic. However, such closures can detrimentally impact economic and social life. Methods Here, we couple a decision analytic approach with a mathematical model of influenza transmission to estimate the impact of school closures in terms of epidemiological and cost effectiveness. Our method assumes that the transmissibility and the severity of the disease are uncertain, and evaluates several closure and reopening strategies that cover a range of thresholds in school-aged prevalence (SAP) and closure durations. Results Assuming a willingness to pay per quality adjusted life-year (QALY) threshold equal to the US per capita GDP ($46,000), we found that the cost effectiveness of these strategies is highly dependent on the severity and on a willingness to pay per QALY. For severe pandemics, the preferred strategy couples the earliest closure trigger (0.5% SAP) with the longest duration closure (24 weeks) considered. For milder pandemics, the preferred strategies also involve the earliest closure trigger, but are shorter duration (12 weeks for low transmission rates and variable length for high transmission rates). Conclusions These findings highlight the importance of obtaining early estimates of pandemic severity and provide guidance to public health decision-makers for effectively tailoring school closures strategies in response to a newly emergent influenza pandemic. PMID:22713694

Closure Plan for the Area 5 Radioactive Waste Management Site at the Nevada Test Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

NSTec Environmental Management

The Area 5 Radioactive Waste Management Site (RMWS) at the Nevada Test Site (NTS) is managed and operated by National Security Technologies, LLC (NSTec), for the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO). This document is the first update of the preliminary closure plan for the Area 5 RWMS at the NTS that was presented in the Integrated Closure and Monitoring Plan (DOE, 2005a). The major updates to the plan include a new closure schedule, updated closure inventory, updated site and facility characterization data, the Title II engineering cover design, and the closure processmore » for the 92-Acre Area of the RWMS. The format and content of this site-specific plan follows the Format and Content Guide for U.S. Department of Energy Low-Level Waste Disposal Facility Closure Plans (DOE, 1999a). This interim closure plan meets closure and post-closure monitoring requirements of the order DOE O 435.1, manual DOE M 435.1-1, Title 40 Code of Federal Regulations (CFR) Part 191, 40 CFR 265, Nevada Administrative Code (NAC) 444.743, and Resource Conservation and Recovery Act (RCRA) requirements as incorporated into NAC 444.8632. The Area 5 RWMS accepts primarily packaged low-level waste (LLW), low-level mixed waste (LLMW), and asbestiform low-level waste (ALLW) for disposal in excavated disposal cells.« less

Particulate contamination from siliconized rubber closures for freeze drying.

PubMed

Gebhardt, U; Grumbridge, N A; Knoch, A

1996-01-01

It can be shown that siliconized closures for freeze drying may cause the opalescence and turbidity observed in freeze-dried products after reconstitution. Closures of different rubber composition show different intensities of turbidity when treated identically with the same quantity and type of silicone oil. Clear solutions are obtained after reconstitution if ETFE-coated closures are used instead of siliconized closures. Samples stored at 4 degrees C for up to 6 months show no change in the intensity of turbidity, while the turbidity of samples manufactured with siliconized closures and stored at higher temperatures increase with time. Samples with ETFE-coated closures show clear solutions when stored at 25 degrees C and 37 degrees C for up to 6 months and at 45 degrees C for 3 months. After 6 months only a very weak opalescence could be observed in these samples.

[Epidemiologic and economic effectiveness of school closure during influenza epidemics and pandemics].

PubMed

Gendon, Iu Z; Vasil'ev, Iu M

2012-01-01

Epidemiologic and economic effectiveness of school closure during influenza epidemics and pandemics is discussed. Optimal effect of school closure is observed when this measure is taken at the start of the epidemic or pandemic and for a sufficiently long time. School closure during high morbidity among schoolchildren, in the middle (at the peak) and by the end of epidemic or pandemic does not influence significantly the spread of influenza or morbidity. Significant economic losses and other negative consequences of school closure are noted. School closure may be the most appropriate during the emergence of influenza pandemic when the pandemic vaccine is not yet available, however timely mass immunization of schoolchildren against influenza may be a more appropriate measure than school closure for the reduction of influenza morbidity and spread during seasonal influenza epidemics.

Modeling the Interactions Between Multiple Crack Closure Mechanisms at Threshold

NASA Technical Reports Server (NTRS)

Newman, John A.; Riddell, William T.; Piascik, Robert S.

2003-01-01

A fatigue crack closure model is developed that includes interactions between the three closure mechanisms most likely to occur at threshold; plasticity, roughness, and oxide. This model, herein referred to as the CROP model (for Closure, Roughness, Oxide, and Plasticity), also includes the effects of out-of plane cracking and multi-axial loading. These features make the CROP closure model uniquely suited for, but not limited to, threshold applications. Rough cracks are idealized here as two-dimensional sawtooths, whose geometry induces mixed-mode crack- tip stresses. Continuum mechanics and crack-tip dislocation concepts are combined to relate crack face displacements to crack-tip loads. Geometric criteria are used to determine closure loads from crack-face displacements. Finite element results, used to verify model predictions, provide critical information about the locations where crack closure occurs.

Single-site neural tube closure in human embryos revisited.

PubMed

de Bakker, Bernadette S; Driessen, Stan; Boukens, Bastiaan J D; van den Hoff, Maurice J B; Oostra, Roelof-Jan

2017-10-01

Since the multi-site closure theory was first proposed in 1991 as explanation for the preferential localizations of neural tube defects, the closure of the neural tube has been debated. Although the multi-site closure theory is much cited in clinical literature, single-site closure is most apparent in literature concerning embryology. Inspired by Victor Hamburgers (1900-2001) statement that "our real teacher has been and still is the embryo, who is, incidentally, the only teacher who is always right", we decided to critically review both theories of neural tube closure. To verify the theories of closure, we studied serial histological sections of 10 mouse embryos between 8.5 and 9.5 days of gestation and 18 human embryos of the Carnegie collection between Carnegie stage 9 (19-21 days) and 13 (28-32 days). Neural tube closure was histologically defined by the neuroepithelial remodeling of the two adjoining neural fold tips in the midline. We did not observe multiple fusion sites in neither mouse nor human embryos. A meta-analysis of case reports on neural tube defects showed that defects can occur at any level of the neural axis. Our data indicate that the human neural tube fuses at a single site and, therefore, we propose to reinstate the single-site closure theory for neural tube closure. We showed that neural tube defects are not restricted to a specific location, thereby refuting the reasoning underlying the multi-site closure theory. Clin. Anat. 30:988-999, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Biomechanical Testing and Histologic Examination of Intradermal Skin Closure in Dogs Using Barbed Suture Device and Non-Barbed Monofilament Suture.

PubMed

Law, Andy Y; Butler, James R; Patnaik, Sourav S; Cooley, James A; Elder, Steven H

2017-01-01

To compare the biomechanical strength and histologic features of 3-0 Glycomer™ 631 barbed suture (V-LOC™ 90 Absorbable Wound Closure Device, Covidien, Mansfield, MA) to non-barbed 3-0 Glycomer™ 631 suture (Biosyn™, Covidien) for intradermal skin wound closure in the dog. Randomized, factorial, in vivo. Eighteen purpose-bred, mature male, and female hound dogs. Eighteen adult hound dogs were randomly assigned to 1 of 3 groups designated by postoperative day of assessment. Six skin incisions were made along the dorsum in the thoracolumbar region of each dog with an equal number (n=3) randomly assigned to closure with barbed or non-barbed suture. Six dogs were euthanatized on postoperative days 3, 10, and 14, respectively. Two additional incisions were made on each dog after euthanasia for baseline data (Day 0). The skin incision specimens were harvested for biomechanical testing and histologic evaluation. Non-barbed closure had significantly higher maximum load at failure (P<.001) and stiffness (P<.001) than barbed closure regardless of day. The average tissue reaction score was significantly higher for barbed closure (P=.008), regardless of day. Suturing time for barbed closures was significantly shorter. There was no significant difference in frequency of complications between closures. Barbed Glycomer™ 631 closures had a significantly lower maximum load at failure and stiffness, and higher average tissue reaction scores, but showed no difference in short term outcome for intradermal closure of dorsally located skin incisions in dogs. © 2016 The American College of Veterinary Surgeons.

40 CFR 265.117 - Post-closure care and use of property.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... 265.117 Section 265.117 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID.... (a)(1) Post-closure care for each hazardous waste management unit subject to the requirements of... this part. (2) Any time preceding closure of a hazardous waste management unit subject to post-closure...

Gestalt concept of closure: a construct without closure.

PubMed

Wasserstein, Jeanette

2002-12-01

This comment reviews the original Gestalt literature which introduced the concept of 'closure'. It is argued that the meaning of 'closure' was confounded in the source literature and, thus, the term connotes more than it denotes. Research based on different measures of this ambiguous construct inevitably may not always converge.

40 CFR 267.143 - Financial assurance for closure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Financial assurance for closure. 267... PERMIT Financial Requirements § 267.143 Financial assurance for closure. The owner or operator must establish financial assurance for closure of each storage or treatment unit that he owns or operates. In...

40 CFR 264.280 - Closure and post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Closure and post-closure care. 264.280 Section 264.280 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES... § 264.278, except that soil-pore liquid monitoring may be terminated 90 days after the last application...

Influence of fatigue crack wake length and state of stress on crack closure

NASA Technical Reports Server (NTRS)

Telesman, J.; Fisher, D. M.

1986-01-01

The location of crack closure with respect to crack wake and specimen thickness under different loading conditions was determined. The rate of increase of K sub CL in the crack wake was found to be significantly higher for plasticity induced closure in comparison to roughness induced closure. Roughness induced closure was uniform throughout the thickness of the specimen while plasticity induced closure levels were 50 percent higher in the near surface region than in the midthickness. The influence of state of stress on low-high load interaction effects was also examined. Load interaction effects differed depending upon the state of stress and were explained in terms of delta K sub eff.

Influence of fatigue crack wake length and state of stress on crack closure

NASA Technical Reports Server (NTRS)

Telesman, Jack; Fisher, Douglas M.

1988-01-01

The location of crack closure with respect to crack wake and specimen thickness under different loading conditions was determined. The rate of increase of K sub CL in the crack wake was found to be significantly higher for plasticity induced closure in comparison to roughness induced closure. Roughness induced closure was uniform throughout the thickness of the specimen while plasticity induced closure levels were 50 percent higher in the near surface region than in the midthickness. The influence of state of stress on low-high load interaction effects was also examined. Load interaction effects differed depending upon the state of stress and were explained in terms of delta K sub eff.

Three point-advancement closure for skin defects.

PubMed

Tamir, G; Birkby, C S; Berg, D

1999-10-01

Circular skin defects are common following Mohs' surgery. Traditional closure (primary, flap, or graft) may involve extensive surgery. Multidirectional advancement closures such as the purse-string closure have been advocated as another useful tool in such cases. To describe a variation on purse-string closure that, in certain cases, is an excellent alternative to other reconstructions, and will provide good cosmetic and functional outcome. A three-point anchoring suture is placed after undermining to advance the surrounding tissue toward the centre, creating a "Mercedes Benz" or tripod closure following removal of "dog-ears." Circular wounds in designated areas can be more easily closed, creating well-tolerated, favourable scars. Large wounds may be closed with the advantage of avoidance of larger flaps, of decreased wound healing compared to second intention, and of minimizing removal of healthy tissue. An initial trial of closure with this method does not limit subsequent use of other repairs should it be less than satisfactory.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, Duane C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member.

Amnioserosa cell constriction but not epidermal actin cable tension autonomously drives dorsal closure.

PubMed

Pasakarnis, Laurynas; Frei, Erich; Caussinus, Emmanuel; Affolter, Markus; Brunner, Damian

2016-11-01

Tissue morphogenesis requires coordination of multiple force-producing components. During dorsal closure in fly embryogenesis, an epidermis opening closes. A tensioned epidermal actin/MyosinII cable, which surrounds the opening, produces a force that is thought to combine with another MyosinII force mediating apical constriction of the amnioserosa cells that fill the opening. A model proposing that each force could autonomously drive dorsal closure was recently challenged by a model in which the two forces combine in a ratchet mechanism. Acute force elimination via selective MyosinII depletion in one or the other tissue shows that the amnioserosa tissue autonomously drives dorsal closure while the actin/MyosinII cable cannot. These findings exclude both previous models, although a contribution of the ratchet mechanism at dorsal closure onset remains likely. This shifts the current view of dorsal closure being a combinatorial force-component system to a single tissue-driven closure event.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, D.C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member. 5 figs.

A comparison of three algebraic stress closures for combustor flow calculations

NASA Technical Reports Server (NTRS)

Nikjooy, M.; So, R. M. C.; Hwang, B. C.

1985-01-01

A comparison is made of the performance of two locally nonequilibrium and one equilibrium algebraic stress closures in calculating combustor flows. Effects of four different pressure-strain models on these closure models are also analyzed. The results show that the pressure-strain models have a much greater influence on the calculated mean velocity and turbulence field than the algebraic stress closures, and that the best mean strain model for the pressure-strain terms is that proposed by Launder, Reece and Rodi (1975). However, the equilibrium algebraic stress closure with the Rotta return-to-isotropy model (1951) for the pressure-strain terms gives as good a correlation with measurements as when the Launder et al. mean strain model is included in the pressure-strain model. Finally, comparison of the calculations with the standard k-epsilon closure results show that the algebraic stress closures are better suited for simple turbulent flow calculations.

Crack closure, a literature study

NASA Astrophysics Data System (ADS)

Holmgren, M.

1993-08-01

In this report crack closure is treated. The state of the art is reviewed. Different empirical formulas for determining the crack closure are compared with each other, and their benefits are discussed. Experimental techniques for determining the crack closure stress are discussed, and some results from fatigue tests are also reported. Experimental data from the literature are reported.

40 CFR 264.144 - Cost estimate for post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... § 264.145. For owners or operators using the financial test or corporate guarantee, the post-closure... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Cost estimate for post-closure care... FACILITIES Financial Requirements § 264.144 Cost estimate for post-closure care. (a) The owner or operator of...

40 CFR 264.144 - Cost estimate for post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... § 264.145. For owners or operators using the financial test or corporate guarantee, the post-closure... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Cost estimate for post-closure care... FACILITIES Financial Requirements § 264.144 Cost estimate for post-closure care. (a) The owner or operator of...

40 CFR 264.144 - Cost estimate for post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... § 264.145. For owners or operators using the financial test or corporate guarantee, the post-closure... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Cost estimate for post-closure care... FACILITIES Financial Requirements § 264.144 Cost estimate for post-closure care. (a) The owner or operator of...

40 CFR 264.144 - Cost estimate for post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 264.145. For owners or operators using the financial test or corporate guarantee, the post-closure... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Cost estimate for post-closure care... FACILITIES Financial Requirements § 264.144 Cost estimate for post-closure care. (a) The owner or operator of...

40 CFR 264.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in accordance with § 264.145(i). (f) Financial test and corporate guarantee for post-closure care. (1... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Financial assurance for post-closure... DISPOSAL FACILITIES Financial Requirements § 264.145 Financial assurance for post-closure care. The owner...

76 FR 10778 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Coastal Migratory Pelagic...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-28

... Migratory Pelagic Resources of the Gulf of Mexico and South Atlantic; Closure AGENCY: National Marine...: Temporary rule; closure. SUMMARY: NMFS closes the commercial sector for king mackerel in the Florida east coast subzone. This closure is necessary to protect the Gulf king mackerel resource. DATES: The closure...

40 CFR 264.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in accordance with § 264.145(i). (f) Financial test and corporate guarantee for post-closure care. (1... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Financial assurance for post-closure... DISPOSAL FACILITIES Financial Requirements § 264.145 Financial assurance for post-closure care. The owner...

40 CFR 264.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... in accordance with § 264.145(i). (f) Financial test and corporate guarantee for post-closure care. (1... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Financial assurance for post-closure... DISPOSAL FACILITIES Financial Requirements § 264.145 Financial assurance for post-closure care. The owner...

40 CFR 264.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in accordance with § 264.145(i). (f) Financial test and corporate guarantee for post-closure care. (1... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Financial assurance for post-closure... DISPOSAL FACILITIES Financial Requirements § 264.145 Financial assurance for post-closure care. The owner...

40 CFR 264.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in accordance with § 264.145(i). (f) Financial test and corporate guarantee for post-closure care. (1... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Financial assurance for post-closure... DISPOSAL FACILITIES Financial Requirements § 264.145 Financial assurance for post-closure care. The owner...

31 CFR 413.1 - Closure of streets.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Closure of streets. 413.1 Section 413.1 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY CLOSURE OF STREETS NEAR THE WHITE HOUSE § 413.1 Closure of streets. (a) District...

31 CFR 413.1 - Closure of streets.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Closure of streets. 413.1 Section 413.1 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY CLOSURE OF STREETS NEAR THE WHITE HOUSE § 413.1 Closure of streets. (a) District...

31 CFR 413.1 - Closure of streets.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Closure of streets. 413.1 Section 413.1 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY CLOSURE OF STREETS NEAR THE WHITE HOUSE § 413.1 Closure of streets. (a) District...

31 CFR 413.1 - Closure of streets.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Closure of streets. 413.1 Section 413.1 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY CLOSURE OF STREETS NEAR THE WHITE HOUSE § 413.1 Closure of streets. (a) District...

31 CFR 413.1 - Closure of streets.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false Closure of streets. 413.1 Section 413.1 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY CLOSURE OF STREETS NEAR THE WHITE HOUSE § 413.1 Closure of streets. (a) District...

40 CFR 258.72 - Financial assurance for post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... care. 258.72 Section 258.72 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID... dollars, of the cost of hiring a third party to conduct post-closure care for the MSWLF unit in compliance with the post-closure plan developed under § 258.61 of this part. The post-closure cost estimate used...

AN EVALUATION OF TWO GROUND-BASED CROWN CLOSURE ESTIMATION TECHNIQUES COMPARED TO CROWN CLOSURE ESTIMATES DERIVED FROM HIGH RESOLUTION IMAGERY

EPA Science Inventory

Two ground-based canopy closure estimation techniques, the Spherical Densitometer (SD) and the Vertical Tube (VT), were compared for the effect of deciduous understory on dominantlco-dominant crown closure estimates in even-aged loblolly (Pinus taeda) pine stands located in the N...

Construction of a wireless communication contact closure system for liquid chromatography with multiple parallel mass spectrometers and other detectors

USDA-ARS?s Scientific Manuscript database

A contact closure system has been constructed and implemented that utilizes two contact closure sender boards that communicate wirelessly to four contact closure receiver boards to distribute start signals from two or three liquid chromatographs to fourteen instruments, pumps, detectors, or other co...

AN EVALUATION OF TWO GROUND-BASED CROWN CLOSURE ESTIMATION TECHNIQUES COMPARED TO CROWN CLOSURE ESTIMATES DERIVED FROM HIGH RESOLUTION IMAGERY

EPA Science Inventory

Two ground-based canopy closure estimation techniques, the Spherical Densitometer (SD) and the Vertical Tube (VT), were compared for the effect of deciduous understory on dominant/co-dominant crown closure estimates in even-aged loblolly (Pinus taeda) pine stands located in the N...

77 FR 60319 - Harbor Porpoise Take Reduction Plan; Coastal Gulf of Maine Closure Area Established With a...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-03

...-XC099 Harbor Porpoise Take Reduction Plan; Coastal Gulf of Maine Closure Area Established With a... Atmospheric Administration (NOAA), Commerce. ACTION: Establishment of the Coastal Gulf of Maine Closure Area... Service (NMFS) announces the establishment of the Coastal Gulf of Maine Closure Area under the Harbor...

40 CFR 146.71 - Closure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Waste Injection Wells § 146.71 Closure. (a) Closure Plan. The owner or operator of a Class I hazardous waste injection well shall prepare, maintain, and comply with a plan for closure of the well that meets... of material to be used in plugging; (iv) The method of placement of the plugs; (v) Any proposed test...

Leaf-on canopy closure in broadleaf deciduous forests predicted during winter

USGS Publications Warehouse

Twedt, Daniel J.; Ayala, Andrea J.; Shickel, Madeline R.

2015-01-01

Forest canopy influences light transmittance, which in turn affects tree regeneration and survival, thereby having an impact on forest composition and habitat conditions for wildlife. Because leaf area is the primary impediment to light penetration, quantitative estimates of canopy closure are normally made during summer. Studies of forest structure and wildlife habitat that occur during winter, when deciduous trees have shed their leaves, may inaccurately estimate canopy closure. We estimated percent canopy closure during both summer (leaf-on) and winter (leaf-off) in broadleaf deciduous forests in Mississippi and Louisiana using gap light analysis of hemispherical photographs that were obtained during repeat visits to the same locations within bottomland and mesic upland hardwood forests and hardwood plantation forests. We used mixed-model linear regression to predict leaf-on canopy closure from measurements of leaf-off canopy closure, basal area, stem density, and tree height. Competing predictive models all included leaf-off canopy closure (relative importance = 0.93), whereas basal area and stem density, more traditional predictors of canopy closure, had relative model importance of ≤ 0.51.

Corrective Action Decision Document/Closure Report for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada, Revision 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthews, Patrick

2013-09-01

This Corrective Action Decision Document/Closure Report presents information supporting the closure of Corrective Action Unit (CAU) 105: Area 2 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada. CAU 105 comprises the following five corrective action sites (CASs): -02-23-04 Atmospheric Test Site - Whitney Closure In Place -02-23-05 Atmospheric Test Site T-2A Closure In Place -02-23-06 Atmospheric Test Site T-2B Clean Closure -02-23-08 Atmospheric Test Site T-2 Closure In Place -02-23-09 Atmospheric Test Site - Turk Closure In Place The purpose of this Corrective Action Decision Document/Closure Report is to provide justification and documentation supporting the recommendation that nomore » further corrective action is needed for CAU 105 based on the implementation of the corrective actions. Corrective action investigation (CAI) activities were performed from October 22, 2012, through May 23, 2013, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites; and in accordance with the Soils Activity Quality Assurance Plan, which establishes requirements, technical planning, and general quality practices.« less

Hospital closures had no measurable impact on local hospitalization rates or mortality rates, 2003-11.

PubMed

Joynt, Karen E; Chatterjee, Paula; Orav, E John; Jha, Ashish K

2015-05-01

The Affordable Care Act (ACA) set in motion payment changes that could put pressure on hospital finances and lead some hospitals to close. Understanding the impact of closures on patient care and outcomes is critically important. We identified 195 hospital closures in the United States between 2003 and 2011. We found no significant difference between the change in annual mortality rates for patients living in hospital service areas (HSAs) that experienced one or more closures and the change in rates in matched HSAs without a closure (5.5 percent to 5.2 percent versus 5.4 percent to 5.4 percent, respectively). Nor was there a significant difference in the change in all-cause mortality rates following hospitalization (9.1 percent to 8.2 percent in HSAs with a closure versus 9.0 percent to 8.4 percent in those without a closure). HSAs with a closure had a drop in readmission rates compared to controls (19.4 percent to 18.2 percent versus 18.8 percent to 18.3 percent). Overall, we found no evidence that hospital closures were associated with worse outcomes for patients living in those communities. These findings may offer reassurance to policy makers and clinical leaders concerned about the potential acceleration of hospital closures as a result of health care reform. Project HOPE—The People-to-People Health Foundation, Inc.

Subcostal closure technique for prevention of postthoracotomy pain syndrome.

PubMed

Hong, Kipyo; Bae, Mikyung; Han, Sora

2016-09-01

The purpose of this study was to evaluate the efficacy of our subcostal closure technique in prevention of postthoracotomy pain syndrome. From July 2012 to March 2015, 29 patients in whom a lobectomy was indicated underwent a thoracotomy. The thoracotomy wounds were closed using a subcostal closure technique (subcostal closure group) and outcomes were compared with 31 patients who underwent video-assisted thoracoscopic surgery (thoracoscopy group). The duration of oral opioid consumption was evaluated from medical records, and postoperative pain was evaluated by telephone interview conducted by a trained nurse practitioner who was unaware of the patient's group. Pain scores were higher in the thoracoscopy group compared to the subcostal closure group, reaching statistical significance (Numeric Rating Scale 0.55 ± 0.948 in the subcostal closure group vs. 1.84 ± 1.614 in the thoracoscopy group; p < 0.001, Clinical Pain Scale 0.24 ± 0.435 in the subcostal closure group vs. 0.81 ± 0.703 in the thoracoscopy group; p < 0.001). The number of patients who consumed oral opioids for longer than 2 months after the operation was significantly greater in the thoracoscopy group than the subcostal closure group (6.9% in the subcostal closure group vs. 32.3% in the thoracoscopy group; p = 0.022). The subcostal closure technique is useful to prevent postthoracotomy pain syndrome. © The Author(s) 2016.

Multidisciplinary management of patent foramen ovale (PFO) and cryptogenic stroke/TIA

PubMed Central

Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Eriksson, Peter; Dellborg, Mikael

2013-01-01

Purpose Patent foramen ovale (PFO) has been implicated as a risk factor for cryptogenic ischemic stroke (CS). However, there is still a lack of widely accepted, undisputed indications for PFO closure. The present study describes the concept of the multidisciplinary PFO conference and a decision making process for closure versus no closure that was developed into a formalized clinical algorithm, and presents the results of implementing these, in terms of number and proportion of PFO closures as well as repeat referrals. Design Five specialists in neurology, cardiology, internal medicine, thromboembolism, and echocardiography evaluated the clinical data of 311 patients at PFO conferences during 2006 to 2009. The main criteria for closure were patients with first-ever CS with PFO and atrial septal aneurysm, or patients with recurrent CS and PFO without atrial septal aneurysm. Results A total of 143 patients (46%) were accepted for closure and 167 patients were rejected. Patients accepted for closure were younger (mean 50 years versus 58 years) (P < 0.001). The acceptance rate for PFO closure was similar throughout these years, with an average of 45%. Three of 167 patients (1.8%) initially rejected for PFO closure were re-referred due to recurrent stroke, and the PFO closure was subsequently performed. Conclusion The acceptance rate of less than 50% in the present study underscores the complex relationship between CS and PFO. Whatever the criteria used for PFO closure, any unit caring for these patients needs to have a rigorous process to avoid overtreatment as well as undertreatment and to ensure that personal preferences and economic incentives do not steer the selection process. Our algorithm provides a stable acceptance rate and a low rate of repeat referrals. PMID:24082787

Modeling and Simulating Passenger Behavior for a Station Closure in a Rail Transit Network

PubMed Central

Yin, Haodong; Han, Baoming; Li, Dewei; Wu, Jianjun; Sun, Huijun

2016-01-01

A station closure is an abnormal operational situation in which the entrances or exits of a rail transit station have to be closed for some time due to an unexpected incident. A novel approach is developed to estimate the impacts of the alternative station closure scenarios on both passenger behavioral choices at the individual level and passenger demand at the disaggregate level in a rail transit network. Therefore, the contributions of this study are two-fold: (1) A basic passenger behavior optimization model is mathematically constructed based on 0–1 integer programming to describe passengers’ responses to alternative origin station closure scenarios and destination station closure scenarios; this model also considers the availability of multi-mode transportation and the uncertain duration of the station closure; (2) An integrated solution algorithm based on the passenger simulation is developed to solve the proposed model and to estimate the effects of a station closure on passenger demand in a rail transit network. Furthermore, 13 groups of numerical experiments based on the Beijing rail transit network are performed as case studies with 2,074,267 records of smart card data. The comparisons of the model outputs and the manual survey show that the accuracy of our proposed behavior optimization model is approximately 80%. The results also show that our model can be used to capture the passenger behavior and to quantitatively estimate the effects of alternative closure scenarios on passenger flow demand for the rail transit network. Moreover, the closure duration and its overestimation greatly influence the individual behavioral choices of the affected passengers and the passenger demand. Furthermore, if the rail transit operator can more accurately estimate the closure duration (namely, as g approaches 1), the impact of the closure can be somewhat mitigated. PMID:27935963

Variability in school closure decisions in response to 2009 H1N1: a qualitative systems improvement analysis

PubMed Central

2011-01-01

Background School closure was employed as a non-pharmaceutical intervention against pandemic 2009 H1N1, particularly during the first wave. More than 700 schools in the United States were closed. However, closure decisions reflected significant variation in rationales, decision triggers, and authority for closure. This variability presents the opportunity for improved efficiency and decision-making. Methods We identified media reports relating to school closure as a response to 2009 H1N1 by monitoring high-profile sources and searching Lexis-Nexis and Google news alerts, and reviewed reports for key themes. News stories were supplemented by observing conference calls and meetings with health department and school officials, and by discussions with decision-makers and community members. Results There was significant variation in the stated goal of closure decision, including limiting community spread of the virus, protecting particularly vulnerable students, and responding to staff shortages or student absenteeism. Because the goal of closure is relevant to its timing, nature, and duration, unclear rationales for closure can challenge its effectiveness. There was also significant variation in the decision-making authority to close schools in different jurisdictions, which, in some instances, was reflected in open disagreement between school and public health officials. Finally, decision-makers did not appear to expect the level of scientific uncertainty encountered early in the pandemic, and they often expressed significant frustration over changing CDC guidance. Conclusions The use of school closure as a public health response to epidemic disease can be improved by ensuring that officials clarify the goals of closure and tailor closure decisions to those goals. Additionally, authority to close schools should be clarified in advance, and decision-makers should expect to encounter uncertainty disease emergencies unfold and plan accordingly. PMID:21284865

Modeling and Simulating Passenger Behavior for a Station Closure in a Rail Transit Network.

PubMed

Yin, Haodong; Han, Baoming; Li, Dewei; Wu, Jianjun; Sun, Huijun

2016-01-01

A station closure is an abnormal operational situation in which the entrances or exits of a rail transit station have to be closed for some time due to an unexpected incident. A novel approach is developed to estimate the impacts of the alternative station closure scenarios on both passenger behavioral choices at the individual level and passenger demand at the disaggregate level in a rail transit network. Therefore, the contributions of this study are two-fold: (1) A basic passenger behavior optimization model is mathematically constructed based on 0-1 integer programming to describe passengers' responses to alternative origin station closure scenarios and destination station closure scenarios; this model also considers the availability of multi-mode transportation and the uncertain duration of the station closure; (2) An integrated solution algorithm based on the passenger simulation is developed to solve the proposed model and to estimate the effects of a station closure on passenger demand in a rail transit network. Furthermore, 13 groups of numerical experiments based on the Beijing rail transit network are performed as case studies with 2,074,267 records of smart card data. The comparisons of the model outputs and the manual survey show that the accuracy of our proposed behavior optimization model is approximately 80%. The results also show that our model can be used to capture the passenger behavior and to quantitatively estimate the effects of alternative closure scenarios on passenger flow demand for the rail transit network. Moreover, the closure duration and its overestimation greatly influence the individual behavioral choices of the affected passengers and the passenger demand. Furthermore, if the rail transit operator can more accurately estimate the closure duration (namely, as g approaches 1), the impact of the closure can be somewhat mitigated.

Cost comparison of transcatheter and operative closures of ostium secundum atrial septal defects

PubMed Central

O’Byrne, Michael L.; Gillespie, Matthew J.; Shinohara, Russell T.; Dori, Yoav; Rome, Jonathan J.; Glatz, Andrew C.

2015-01-01

Background Clinical outcomes for transcatheter and operative closures of atrial septal defects (ASDs) are similar. Economic cost for each method has not been well described. Methods A single-center retrospective cohort study of children and adults <30 years of age undergoing closure for single secundum ASD from January 1, 2007, to April 1, 2012, was performed to measure differences in inflation-adjusted cost of operative and transcatheter closures of ASD. A propensity score weight-adjusted multivariate regression model was used in an intention-to-treat analysis. Costs for reintervention and crossover admissions were included in primary analysis. Results A total of 244 subjects were included in the study (64% transcatheter and 36% operative), of which 2% (n = 5) were ≥18 years. Crossover rate from transcatheter to operative group was 3%. Risk of reintervention (P = .66) and 30-day mortality (P = .37) were not significantly different. In a multivariate model, adjusted cost of operative closure was 2012 US $60,992 versus 2012 US $55,841 for transcatheter closure (P < .001). Components of total cost favoring transcatheter closure were length of stay, medications, and follow-up radiologic and laboratory testing, overcoming higher costs of procedure and echocardiography. Professional costs did not differ. The rate of 30-day readmission was greater in the operative cohort, further increasing the cost advantage of transcatheter closure. Sensitivity analyses demonstrated that costs of follow-up visits influenced relative cost but that device closure remained favorable over a broad range of crossover and reintervention rates. Conclusion For single secundum ASD, cost comparison analysis favors transcatheter closure over the short term. The cost of follow-up regimens influences the cost advantage of transcatheter closure. PMID:25965721

Quality of life after percutaneous closure of patent foramen ovale in patients after cryptogenic stroke compared to a normative sample.

PubMed

Mirzada, Naqibullah; Ladenvall, Per; Hansson, Per-Olof; Eriksson, Peter; Taft, Charles; Dellborg, Mikael

2018-04-15

Despite the widespread use of percutaneous closure of patent foramen ovale (PFO) in patients after a cryptogenic stroke, little is known about its impact on health-related quality of life (HRQoL). The aim of this study was to assess HRQoL in these patients compared to PFO patients not considered candidates for percutaneous closure, and to a normal population. A total of 402 patients with cryptogenic stroke or transient ischaemic attack (TIA) who had been referred to our center for PFO closure were invited to a long-term clinical follow-up (mean follow-up 5.5 years; range 3-13 years). HRQoL was assessed using the SF-36 Health Survey and data were compared with an age- and gender-matched reference group from the Swedish SF-36 normative database. Fifteen patients had died and 43 did not answer the SF-36. Of the remaining 344 patients, 208 had undergone PFO closure, and 136 had not. The closure group and reference group reported similar HRQoL levels. However, the non-closure group showed significantly lower HRQoL in role limitation - physical, vitality, general health, mental health (p < 0.05) and social functioning (p = 0.05) than the reference group and also had significantly lower scores than the closure group, correcting for age differences, on physical functioning, role limitation - physical, vitality and general health (p < 0.05). Non-closure patients had lower HRQoL than their counterparts in the normal population and the closure group. Percutaneous PFO closure is associated with a favorable quality of life. Copyright © 2018 Elsevier B.V. All rights reserved.

Active ocular vergence improves postural control in elderly as close viewing distance with or without a single cognitive task.

PubMed

Matheron, Eric; Yang, Qing; Delpit-Baraut, Vincent; Dailly, Olivier; Kapoula, Zoï

2016-01-01

Performance of the vestibular, visual, and somatosensory systems decreases with age, reducing the capacity of postural control, and increasing the risk of falling. The purpose of this study is to measure the effects of vision, active vergence eye movements, viewing distance/vergence angle and a simple cognitive task on postural control during an upright stance, in completely autonomous elderly individuals. Participated in the study, 23 elderly subjects (73.4 ± 6.8 years) who were enrolled in a center dedicated to the prevention of falling. Their body oscillations were measured with the DynaPort(®) device, with three accelerometers, placed at the lumbosacral level, near the center of mass. The conditions were the following: eyes open fixating on LED at 20 cm or 150 cm (vergence angle 17.0° and 2.3° respectively) with or without additional cognitive tasks (counting down from one hundred), performing active vergence by alternating the fixation between the far and the near LED (convergence and divergence), eyes closed after having fixated the far LED. The results showed that the postural stability significantly decreased when fixating on the LED at a far distance (weak convergence angle) with or without cognitive tasks; active convergence-divergence between the LEDs improved the postural stability while eye closure decreased it. The privilege of proximity (with increased convergence at near), previously established with foot posturography, is shown here to be valid for accelerometry with the center of mass in elderly. Another major result is the beneficial contribution of active vergence eye movements to better postural stability. The results bring new perspectives for the role of eye movement training to preserve postural control and autonomy in elderly. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Prevalence and Determinants of Glaucoma in Citizens of Qatar Aged 40 Years or Older: A Community-Based Survey

PubMed Central

Al-Mansouri, Fatma A.; Kanaan, Aida; Gamra, Hamad; Khandekar, Rajiv; Hashim, Shakeel P.; Al Qahtani, Omar; Ahmed, Mohd. Farouk

2011-01-01

Background: We present the prevalence and determinants of glaucoma among subjects 40 years of age and older in Qatar. Materials and Methods: This community-based survey was held in 2009 at 49 randomly selected clusters. Demographic details and history of glaucoma was collected by the nurses. Ophthalmologists evaluated the optic disc and retina using a digital camera housed in a mobile van. Visual field was tested with an automated perimeter, the intraocular pressure with an applanation tonometer and the angle of the anterior chamber by gonioscopy. A panel of glaucoma experts diagnosed subjects with glaucoma. Results: This survey enrolled 3,149 (97.3%) participants. The age- and sex-adjusted prevalence of glaucoma in the population aged 40 years and older was 1.73% (95% confidence intervals [CI] 1.69-1.77). Accordingly, 5,641 individuals in this age group in Qatar would have glaucoma. Chronological age of 60 years and older (Odds ratio [OR] 11.1) and the presence of myopia (OR 1.78) were predictors of glaucoma. Open-angle glaucoma was diagnosed in 44 (65.7%) individuals with glaucoma. In nine (13.4%) and 15 (20.9%) subjects, angle closure glaucoma and other (post-traumatic, pseudoexfoliation) glaucoma were present. Bilateral blindness (vision <3/60) and severe visual impairment (<6/60) were found in four (6%) and three (4.5%) subjects with glaucoma, respectively. Glaucoma was treated in 36 (54%) subjects. Conclusions: The prevalence of glaucoma among citizens of Qatar aged 40 years and older was 1.71%. Glaucoma was associated with the age of 60 years and older and the presence of myopia. PMID:21731325

Prevalence, types and awareness of glaucoma in a multi-ethnic population in rural China: the Yunnan Minority Eye Study.

PubMed

Pan, Chen-Wei; Zhao, Chun-Hua; Yu, Min-Bin; Cun, Qing; Chen, Qin; Shen, Wei; Li, Jun; Xu, Jian-Gang; Yuan, Yuansheng; Zhong, Hua

2016-11-01

To determine the prevalence, types and awareness of glaucoma in a rural community in China and to examine possible ethnic variations. The Yunnan Minority Eye Study was a multi-ethnic community-based eye survey using random cluster sampling strategies. 2133 Bai, 2205 Han and 2208 Yi Chinese aged 50 years or older participated in this study. Glaucoma including primary open-angle glaucoma (POAG), primary angle-closure glaucoma (PACG) and secondary glaucoma was defined based on the International Society of Geographical and Epidemiological Ophthalmology criteria. The overall age-standardized prevalence of all glaucoma was 2.6% (95% confidence interval [CI]: 2.2-3.1%) in this population. It was 1.8% (95% CI: 1.1-1.9%) for POAG and 0.5% (95% CI: 0.9-1.6%) for PACG, respectively. Among 29 people with secondary glaucoma, 27 (93%) were blind in at least one eye. The presence of primary open-angle glaucoma was associated with male gender (odds ratio [OR] = 2.94; comparing men with women), Yi ethnicity (OR = 2.27; comparing Yi with Han people), higher IOP (OR = 1.09 per mmHg increase), and the presence of myopia (OR = 1.84). Of the 212 participants with glaucoma, only 38 (18%) were aware of the disease and had been diagnosed previously as having glaucoma or suspected glaucoma. Patients who were better educated tended to be aware of the disease. Significant ethnic difference in the prevalence of POAG was observed in this study. The low awareness of glaucoma highlights the pressing need to increase public awareness of this potentially blinding condition in rural China. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery.

PubMed

Bendella, Habib; Brackmann, Derald E; Goldbrunner, Roland; Angelov, Doychin N

2016-10-01

Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3 mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100 mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3 mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50°-60°. On the other hand, even the light nerve crush (50 mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10°-15°). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats.

Mutation analysis of seven known glaucoma-associated genes in Chinese patients with glaucoma.

PubMed

Huang, Xiaobo; Li, Miaoling; Guo, Xiangming; Li, Shiqiang; Xiao, Xueshan; Jia, Xiaoyun; Liu, Xing; Zhang, Qingjiong

2014-05-13

To evaluate mutations in the MYOC, WDR36, OPTN, OPA1, NTF4, CYP1B1, and LTBP2 genes in a cohort of Chinese patients with primary glaucoma. Genomic DNA was prepared from 683 unrelated patients, including 50 with primary congenital glaucoma, 104 with juvenile open-angle glaucoma (JOAG), 186 with primary open-angle glaucoma (POAG), and 343 with primary angle-closure glaucoma (PACG). Mutations in the seven genes in 257 patients (36 with JOAG, 89 with POAG, and 132 with PACG) were initially analyzed by exome sequencing and then confirmed by Sanger sequencing. In addition, Sanger sequencing was used to detect MYOC mutations in the remaining 426 patients. Exome sequencing identified 19 mutations (6 in MYOC, 9 in WDR36, 3 in OPA1, and 1 in OPTN) in 20 of 257 patients, including 4 patients with JOAG, 8 patients with POAG, and 8 patients with PACG. No mutation was detected in the other three genes. In addition, Sanger sequencing detected additional MYOC mutations in 5 of the remaining 426 patients, including 3 patients with JOAG and 2 patients with POAG. Twenty-two mutations in MYOC, WDR36, OPA1, and OPTN were detected in 25 of the 683 patients with primary glaucoma, including nine MYOC mutations in 11 patients, nine WDR36 mutations in 11 patients, three OPA1 mutations in 3 patients, and one OPTN mutation in a patient who also carried a MYOC mutation. Eight mutations in MYOC, WDR36, and OPA1 in 8 of the 343 PACG patients are of uncertain significance and need to be analyzed further. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Robotic laser tissue welding of sclera using chitosan films.

PubMed

Garcia, Pablo; Mines, Michael J; Bower, Kraig S; Hill, J; Menon, J; Tremblay, Eric; Smith, Benjamin

2009-01-01

To demonstrate the feasibility of scleral wound closure using a novel adhesive made of chitosan film. Five-millimeter scleral lacerations were created in enucleated pig eyes. Casted chitosan films were sized to 7x7 mm patches. Lacerations were sealed with chitosan film alone (7 eyes) or chitosan film followed by laser irradiation using a near infrared laser (1,455 nm) at 350 mW for 6 minutes (7 eyes). Seven eyes were closed with 9-0 nylon suture for comparison (7 eyes). Outcome measures included watertight closure, closure time, and leak pressure. Leak pressure was measured with a pressure transducer attached to tubing continuously monitored intraocular pressure during saline infusion. Watertight closure testing was performed immediately following closure (n = 3 per group) and after 24 hours (n = 3 per group). One eye in each group was fixed in formalin for histology. All wounds were watertight for each closure method. Mean closure time with unlasered chitosan film was 2.24 minutes (range 1.80-3.26, 7 eyes) with a mean leak pressure of 303 mm Hg (range 217-364, 3 eyes). Mean closure time with lasered chitosan was 12.47 minutes (range 11.45-14.15, 7 eyes) with a mean leak pressure of 454.7 mm Hg (range 152-721, 3 eyes). Suture closure required a mean of 4.83 minutes (range 4.03-7.30, 7 eyes) and resulted in a mean leak pressure of 570.3 mm Hg (range 460-646, 3 eyes). Both lasered and unlasered chitosan eyes remained watertight after 24 hours. Histology revealed minimal laser tissue damage in lasered eyes. In this preliminary study chitosan film successfully closed scleral lacerations with and without the application of laser energy. While laser appears to strengthen the closure, it significantly increases the closure time. Chitosan based adhesives hold promise as a scleral wound closure technique.

No evidence that manual closure of the bronchial stump has a lower failure rate than mechanical stapler closure following anatomical lung resection

PubMed Central

Zakkar, Mustafa; Kanagasabay, Robin; Hunt, Ian

2014-01-01

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5–12.5%) than in patients who underwent mechanical closure (1–5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection. PMID:24351508

Greater Success of Primary Fascial Closure of the Open Abdomen: A Retrospective Study Analyzing Applied Surgical Techniques, Success of Fascial Closure, and Variables Affecting the Results.

PubMed

Kääriäinen, M; Kuuskeri, M; Helminen, M; Kuokkanen, H

2017-06-01

The open abdomen technique is a standard procedure in the treatment of intra-abdominal catastrophe. Achieving primary abdominal closure within the initial hospitalization is a main objective. This study aimed to analyze the success of closure rate and the effect of negative pressure wound therapy, mesh-mediated medial traction, and component separation on the results. We present the treatment algorithm used in our institution in open abdomen situations based on these findings. Open abdomen patients (n = 61) treated in Tampere University Hospital from May 2005 until October 2013 were included in the study. Patient characteristics, treatment prior to closure, closure technique, and results were retrospectively collected and analyzed. The first group included patients in whom direct or bridged fascial closure was achieved, and the second group included those in whom only the skin was closed or a free skin graft was used. Background variables and variables related to surgery were compared between groups. Most of the open abdomen patients (72.1%) underwent fascial defect repair during the primary hospitalization, and 70.5% of them underwent direct fascial closure. Negative pressure wound therapy was used as a temporary closure method for 86.9% of the patients. Negative pressure wound therapy combined with mesh-mediated medial traction resulted in the shortest open abdomen time (p = 0.039) and the highest fascial repair rate (p = 0.000) compared to negative pressure wound therapy only or no negative pressure wound therapy. The component separation technique was used for 11 patients; direct fascial closure was achieved in 5 and fascial repair by bridging the defect with mesh was achieved in 6. A total of 8 of 37 (21.6%) patients with mesh repair had a mesh infection. The negative pressure wound therapy combined with mesh-mediated medial traction promotes definitive fascial closure with a high closure rate and a shortened open abdomen time. The component separation technique can be used to facilitate fascial repair but it does not guarantee direct fascial closure in open abdomen patients.

Online Work Force Analyzes Social Media to Identify Consequences of an Unplanned School Closure - Using Technology to Prepare for the Next Pandemic.

PubMed

Rainey, Jeanette J; Kenney, Jasmine; Wilburn, Ben; Putman, Ami; Zheteyeva, Yenlik; O'Sullivan, Megan

During an influenza pandemic, the United States Centers for Disease Control and Prevention (CDC) may recommend school closures. These closures could have unintended consequences for students and their families. Publicly available social media could be analyzed to identify the consequences of an unplanned school closure. As a proxy for an unplanned, pandemic-related school closure, we used the district-wide school closure due to the September 10-18, 2012 teachers' strike in Chicago, Illinois. We captured social media posts about the school closure using the Radian6 social media-monitoring platform. An online workforce from Amazon Mechanical Turk categorized each post into one of two groups. The first group included relevant posts that described the impact of the closure on students and their families. The second group included irrelevant posts that described the political aspects of the strike or topics unrelated to the school closure. All relevant posts were further categorized as expressing a positive, negative, or neutral sentiment. We analyzed patterns of relevant posts and sentiment over time and compared our findings to household surveys conducted after other unplanned school closures. We captured 4,546 social media posts about the district-wide school closure using our search criteria. Of these, 930 (20%) were categorized as relevant by the online workforce. Of the relevant posts, 619 (67%) expressed a negative sentiment, 51 (5%) expressed a positive sentiment, and 260 (28%) were neutral. The number of relevant posts, and especially those with a negative sentiment, peaked on day 1 of the strike. Negative sentiment expressed concerns about childcare, missed school lunches, and the lack of class time for students. This was consistent with findings from previously conducted household surveys. Social media are publicly available and can readily provide information on the impact of an unplanned school closure on students and their families. Using social media to assess the impact of an unplanned school closure due to a public health event would be informative. An online workforce can effectively assist with the review process.

Online Work Force Analyzes Social Media to Identify Consequences of an Unplanned School Closure – Using Technology to Prepare for the Next Pandemic

PubMed Central

Rainey, Jeanette J.; Kenney, Jasmine; Wilburn, Ben; Putman, Ami; Zheteyeva, Yenlik; O’Sullivan, Megan

2016-01-01

Background During an influenza pandemic, the United States Centers for Disease Control and Prevention (CDC) may recommend school closures. These closures could have unintended consequences for students and their families. Publicly available social media could be analyzed to identify the consequences of an unplanned school closure. Methods As a proxy for an unplanned, pandemic-related school closure, we used the district-wide school closure due to the September 10–18, 2012 teachers’ strike in Chicago, Illinois. We captured social media posts about the school closure using the Radian6 social media-monitoring platform. An online workforce from Amazon Mechanical Turk categorized each post into one of two groups. The first group included relevant posts that described the impact of the closure on students and their families. The second group included irrelevant posts that described the political aspects of the strike or topics unrelated to the school closure. All relevant posts were further categorized as expressing a positive, negative, or neutral sentiment. We analyzed patterns of relevant posts and sentiment over time and compared our findings to household surveys conducted after other unplanned school closures. Results We captured 4,546 social media posts about the district-wide school closure using our search criteria. Of these, 930 (20%) were categorized as relevant by the online workforce. Of the relevant posts, 619 (67%) expressed a negative sentiment, 51 (5%) expressed a positive sentiment, and 260 (28%) were neutral. The number of relevant posts, and especially those with a negative sentiment, peaked on day 1 of the strike. Negative sentiment expressed concerns about childcare, missed school lunches, and the lack of class time for students. This was consistent with findings from previously conducted household surveys. Conclusion Social media are publicly available and can readily provide information on the impact of an unplanned school closure on students and their families. Using social media to assess the impact of an unplanned school closure due to a public health event would be informative. An online workforce can effectively assist with the review process. PMID:27655229

Is size the only determinant of delayed abdominal closure in pediatric liver transplant?

PubMed

Khorsandi, Shirin Elizabeth; Day, Arthur William Raven; Cortes, Miriam; Deep, Akash; Dhawan, Anil; Vilca-Melendez, Hector; Heaton, Nigel

2017-03-01

The aim was to determine the factors associated with the use of delayed abdominal closure in pediatric liver transplantation (LT) and whether this affected outcome. From a prospectively maintained database, transplants performed in children (≤18 years) were identified (October 2010 to March 2015). Primary abdominal closure was defined as mass closure performed at time of transplant. Delayed abdominal closure was defined as mass closure not initially performed at the same time as transplant; 230 children underwent LT. Of these, 176 (76.5%) had primary closure. Age was similar between the primary and delayed groups (5.0 ± 4.9 versus 3.9 ± 5.0 years; P = 0.13). There was no difference in the graft-to-recipient weight ratio (GRWR) in the primary and delayed groups (3.4 ± 2.8 versus 4.1 ± 2.1; P = 0.12). Children with acute liver failure (ALF) were more likely to experience delayed closure then those with chronic liver disease (CLD; P < 0.001). GRWR was similar between the ALF and CLD (3.4 ± 2.4 versus 3.6 ± 2.7; P = 0.68). Primary closure children had a shorter hospital stay (P < 0.001), spent fewer days in pediatric intensive care unit (PICU; P = 0.001), and required a shorter duration of ventilation (P < 0.001). Vascular complications (arterial and venous) were similar (primary 8.2% versus delayed 5.6%; P = 0.52). Graft (P = 0.42) and child survival (P = 0.65) in the primary and delayed groups were similar. Considering timing of mass closure after transplant, patients in the early delayed closure group (<6 weeks) were found to experience a shorter time of ventilation (P = 0.03) and in PICU (P = 0.003). In conclusion, ALF was the main determinant of delayed abdominal closure rather than GRWR. The optimal time for delayed closure is within 6 weeks. The use of delayed abdominal closure does not adversely affect graft/child survival. Liver Transplantation 23 352-360 2017 AASLD. © 2016 by the American Association for the Study of Liver Diseases.

Modular low aspect ratio-high beta torsatron

DOEpatents

Sheffield, George V.; Furth, Harold P.

1984-02-07

A fusion reactor device in which the toroidal magnetic field and at least a portion of the poloidal magnetic field are provided by a single set of modular coils. The coils are arranged on the surface of a low aspect ratio toroid in planes having the cylindrical coordinate relationship .phi.=.phi..sub.i +kz where k is a constant equal to each coil's pitch and .phi..sub.i is the toroidal angle at which the i'th coil intersects the z=o plane. The device may be described as a modular, high beta torsation whose screw symmetry is pointed along the systems major (z) axis. The toroid defined by the modular coils preferably has a racetrack minor cross section. When vertical field coils and preferably a toroidal plasma current are provided for magnetic field surface closure within the toroid, a vacuum magnetic field of racetrack shaped minor cross section with improved stability and beta valves is obtained.

Ridges on Europa: Origin by Incremental Ice-Wedging

NASA Technical Reports Server (NTRS)

Melosh, H. J.; Turtle, E. P.

2004-01-01

The surface of Europa is covered by ridges that display a variety of morphologies . The most common type is characterized by a double ridge divided by an axial trough. These ridges are, in general, narrow (typically only a few km across) and remarkably linear. They are up to a few hundred meters high and the inner and outer slopes appear to stand at the angle of repose . A number of diverse mechanisms have been proposed to explain the formation of these ubiquitous features , although none can fully account for all of their observed characteristics. We propose a different formation theory in which accumulation of material within cracks that open during the extensional phase of the tidal cycle prevents complete closure of the cracks during the tidal cycle s compressional phase. This accumulation deforms the surrounding ice and, in time, results in the growth of a landform remarkably similar to the ridges observed on Europa.

40 CFR 265.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2013 CFR

2013-07-01

... of this section in accordance with § 265.145(h). (e) Financial test and corporate guarantee for post... closure and post-closure cost estimates to be covered by the test; (iv) Specify the date ending the owner... Regional Administrator may approve a decrease in the current post-closure cost estimate for which this test...

40 CFR 265.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2010 CFR

2010-07-01

... of this section in accordance with § 265.145(h). (e) Financial test and corporate guarantee for post... closure and post-closure cost estimates to be covered by the test; (iv) Specify the date ending the owner... Regional Administrator may approve a decrease in the current post-closure cost estimate for which this test...

40 CFR 265.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2012 CFR

2012-07-01

... of this section in accordance with § 265.145(h). (e) Financial test and corporate guarantee for post... closure and post-closure cost estimates to be covered by the test; (iv) Specify the date ending the owner... Regional Administrator may approve a decrease in the current post-closure cost estimate for which this test...

40 CFR 265.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2014 CFR

2014-07-01

... of this section in accordance with § 265.145(h). (e) Financial test and corporate guarantee for post... closure and post-closure cost estimates to be covered by the test; (iv) Specify the date ending the owner... Regional Administrator may approve a decrease in the current post-closure cost estimate for which this test...

40 CFR 265.145 - Financial assurance for post-closure care.

Code of Federal Regulations, 2011 CFR

2011-07-01

... of this section in accordance with § 265.145(h). (e) Financial test and corporate guarantee for post... closure and post-closure cost estimates to be covered by the test; (iv) Specify the date ending the owner... Regional Administrator may approve a decrease in the current post-closure cost estimate for which this test...

40 CFR 265.142 - Cost estimate for closure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... must equal the cost of final closure at the point in the facility's active life when the extent and... at all times over the life of the facility. (3) The closure cost estimate may not incorporate any... facility at the time of partial or final closure. (4) The owner or operator may not incorporate a zero cost...

40 CFR 265.142 - Cost estimate for closure.

Code of Federal Regulations, 2011 CFR

2011-07-01

... must equal the cost of final closure at the point in the facility's active life when the extent and... at all times over the life of the facility. (3) The closure cost estimate may not incorporate any... facility at the time of partial or final closure. (4) The owner or operator may not incorporate a zero cost...

Thermochronologic constraints on the Miocene slip history of the South Tibetan detachment system in the Everest region, central Himalaya

NASA Astrophysics Data System (ADS)

Schultz, M.; Hodges, K. V.; Van Soest, M. C.; Wartho, J. A.

2014-12-01

North-dipping, low-angle normal faults of the South Tibetan detachment system (STDS) can be traced for a distance of more than 2000 km along strike and represent an important tectonic characteristic of the Miocene Himalayan-Tibetan orogenic system. Nowhere is the STDS better exposed than the N-S-trending Rongbuk Valley in southern Tibet, where it can be traced down dip from the summit of Everest for a distance of over 30 km before disappearing beneath the valley floor. This places a minimum constraint on Miocene displacement on the feature in this area, but some research groups have suggested ~200 km of displacement based on the difference in metamorphic pressures across the STDS and the very low (< 15˚) primary dip of the structure. We are exploring this issue further using developing (U-Th)/He and 40Ar/39Ar datasets from deformed footwall sillimanite gneisses and leucogranites. Data obtained thus far indicate relatively rapid cooling of the footwall after the intrusion of deformed leucogranites at ca. 16.7 Ma to muscovite 40Ar/39Ar closure temperatures (ca. 15.5-14.2 Ma) and zircon (U-Th)/He closure temperatures (ca. 14.5-11 Ma). We attribute this cooling to tectonic denudation related to ca. 16 Ma STDS slip. Although the (U-Th)/He systematics of apatites from these rocks is complex, our current interpretation of available data places cooling through the ca. 75˚C closure isotherm at ca. 8-9 Ma, which would suggest a significant reduction in cooling rate that is observed in our inverse model runs of the 1D program, HeFTy. Ongoing analyses of footwall samples from ~8 km to the north of our Rongbuk sample localities in the Ra Chu river valley will greatly strengthen our datasets. With the Ra Chu analyses, our datasets will constrain the cooling history of the footwall for more than 20 km perpendicular to the strike of the detachment. Our presentation will also incorporate results from the program Pecube that will contribute to our calculation of the slip rate by specifying the appropriate exhumation rate.

A reliable and safe gastrotomy closure technique assessed in a porcine survival model pilot study: success of the Queen's closure.

PubMed

Hookey, L C; Bielawska, B; Samis, A; Jalink, D; Ellis, R; Khokhotva, V; Hurlbut, D; Mercer, D

2009-06-01

The evolution of NOTES to clinical implementation has been hampered by lack of a reliable, safe, and easy-to-implement technique for closure of the opening created in accessing the peritoneum. The Queen's closure uses a combination of endoscopic clips and loop devices to seal such defects in the stomach wall. This study aimed to assess the Queen's closure in a porcine survival model. Five 30-kg pigs underwent endoscopic transgastric surgery with exploration of the peritoneum. The endoscope was then withdrawn back into the stomach and the closure performed. The animals were recovered, monitored closely, and underwent endoscopy 1 week after surgery. They were then euthanized at 2 (n = 2) and 3 (n = 3) weeks after surgery with subsequent necropsy. The mean procedure time (from intubation of the esophagus to withdrawal of the endoscope) was 79 minutes (range 45-105 minutes) with a mean time of exploration of the peritoneum of 14 minutes (range 8-25 minutes). All animals recovered well with no apparent pain, distress, or signs of infection. Endoscopic examination 1 week after surgery revealed all the closures to be intact and only identifiable by a small ulcer. At necropsy, the gastrotomy site was identifiable only by minor serosal adhesions. Histological study demonstrated full-thickness closure with minimal inflammation. The Queen's closure is a reliable and safe technique that provides full-thickness gastrotomy closure without any observed complications. The technique has proven to be transferable knowledge that holds promise for clinical implementation.

Outcomes of mechanical stapling for postlaryngectomy open pharyngotomy closure.

PubMed

Paddle, Paul; Husain, Inna; McHugh, Lauren; Franco, Ramon

2017-03-01

A total laryngectomy (TL) is performed as a primary or salvage therapy for laryngeal carcinoma. Pharyngotomy closure after TL is typically performed using manual sutures. Automatic stapling devices are routinely used in thoracoabdominal surgery, but have not been widely accepted for use in pharyngotomy closure. Previously described closed stapling techniques of pharyngeal closure do not allow direct evaluation of surgical margins and are limited to endolaryngeal disease. We describe an open technique for pharyngotomy closure using a mechanical stapling device. Retrospective review. A review was conducted of 16 total laryngectomies performed from May 2008 to August 2015 utilizing an Ethicon Endopath ETS Compact-Flex 45 stapler. Sixteen patients (15 male, one female), mean age 69 years, received open TL (14 salvage, two primary) with endostapler pharyngeal closure and primary tracheoesophageal puncture (TEP). Surgical time averaged 218 minutes. Median time to swallowing was 4 days (range, 2-240 days) and mean hospital stay 6 days (range, 3-10 days). Fistula incidence was 31% (5/16) overall and 36% (5/14) in the postradiation patients. Mechanical stapling is a simple method for postlaryngectomy open pharyngotomy closure. This technique allows evaluation of margins, easy primary TEP, and the opportunity for early swallowing and shorter hospital stays. In addition, it can be performed for closure of salvage laryngectomies with rates of fistula formation similar to that found in the literature using suture closure techniques. Future studies are necessary to compare oncological results and surgical complications between the open and closed stapling techniques and to traditional suture closure. 4 Laryngoscope, 127:605-610, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Patent Foramen Ovale Closure in the Setting of Cryptogenic Stroke: A Meta-Analysis of Five Randomized Trials.

PubMed

Garg, Lohit; Haleem, Affan; Varade, Shweta; Sivakumar, Keithan; Shah, Mahek; Patel, Brijesh; Agarwal, Manyoo; Agrawal, Sahil; Leary, Megan; Kluck, Bryan

2018-05-24

The clinical benefit of patent foramen ovale (PFO) closure after cryptogenic stroke has been a topic of debate for decades. Recently, 3 randomized controlled trials of PFO closure in patients with cryptogenic stroke demonstrated a significantly reduced risk of recurrent stroke compared with standard medical therapy alone. This meta-analysis was performed to clarify the efficacy of PFO closure for future stroke prevention in this population. A systematic literature search was undertaken. Published pooled data from 5 large randomized clinical trials (CLOSE, RESPECT, Gore REDUCE, CLOSURE I, and PC) were combined and then subsequently analyzed. Enrolled patients with cryptogenic stroke were assigned to receive standard medical care or to undergo endovascular PFO closure, with a primary outcome of reduction in stroke recurrence rate. Secondary outcomes included rates of transient ischemic attack (TIA), composite outcome of stroke, TIA, and death from all causes, and rates of atrial fibrillation events. We analyzed data for 3412 patients. Transcatheter PFO closure resulted in a statistically significant reduced rate of recurrent stroke, compared with medication alone. Patients undergoing closure were 58% less likely to have another stroke. The number needed to treat with PFO closure to reduce recurrent stroke for 1 patient was 40. Endovascular PFO closure was associated with a reduced risk of recurrent stroke in patients with a prior cryptogenic cerebral infarct. Although the absolute stroke reduction was small, these findings are clinically significant, given the young age of this patient population and the patients' lifetime risk of recurrent stroke. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.