Cross section data have been compiled for electron collisions with hydrogen molecules based on 71 references. Cross sections are collected and reviewed for total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational, and electronic states, dissociation, ionization, emission of radiation, and dissociative attachment. For each process, the recommended values of the cross section are presented for use. The literature has been surveyed through the end of 2006.

IMPORTANCE Air pollution is an important public health concern and the ocular surface is continuously exposed to pollutants in outdoor air. Ocular surface abnormalities related to air pollution are thought to be a subtype of dry eye disease (DED). However, to date, there is no large-scale study evaluating an association between air pollution and DED that includes multiple air pollutants. OBJECTIVE To investigate associations between outdoor air pollution and DED in a Korean population. DESIGN, SETTING, AND PARTICIPANTS A population-based cross-sectional study using data on 16 824 participants in the fifth Korea National Health and Nutrition Examination Survey was conducted from January 1, 2010, to December 31, 2012. Data analysis was conducted from September 1 to 30, 2015. Dry eye disease was defined as previously diagnosed by an ophthalmologist or the presence of frequent ocular pain and discomfort. Outdoor air pollution measurements (mean annual humidity, particulate matter with aerodynamic diameter <10 μm [PM 10 ], ozone, and nitrogen dioxide levels) were collected from 283 national monitoring stations in South Korea. MAIN OUTCOMES AND MEASURES Associations of multiple air pollutants with DED were assessed from multivariable logistic regression analyses. Sociodemographic factors and previously known factors associated with DED were applied as covariates (model 1 controlled for sociodemographic factors and model 2 controlled for sociodemographic, behavioral, and clinical factors). RESULTS Among 16 824 participants (7104 men and 9720 women), higher ozone levels and lower humidity levels were significantly associated with symptoms and diagnosis of DED. In model 1, an increase in ozone levels of 0.003 ppm was significantly associated with symptoms and diagnosis of DED

We investigated relationships between outdoor air pollution and pterygium in Korean adults. This study includes 23,276 adults in population-based cross-sectional data using the Korea National Health and Nutrition Examination Survey 2008–2011. Pterygium was assessed using slit lamp biomicroscopy. Air pollution data (humidity, particulate matter with aerodynamic diameter less than 10 μm [PM10], ozone [O3], nitrogen dioxide [NO2], and sulfur dioxide levels [SO2]) for 2 years preceding the ocular examinations were acquired. Associations of multiple air pollutants with pterygium or pterygium recurrence after surgery were examined using multivariate logistic models, after adjusting for several covariates. Distributed lag models were additionally used for estimating cumulative effects of air pollution on pterygium. None of air pollution factors was significantly associated with pterygium or pterygium recurrence (each P > 0.05). Distributed lag models also showed that air pollution factors were not associated with pterygium or pterygium recurrence in 0-to-2 year lags (each P > 0.05). However, primary pterygium showed a weak association with PM10 after adjusting for covariates (odds ratio [OR] 1.23; [per 5 μg/m3 PM10 increase]; P = 0.023). Aging, male sex, and greater sun exposure were associated with pterygium, while higher education level and myopia were negatively associated with pterygium (each P ≤ 0.001). Male sex and myopia were negatively associated with pterygium recurrence (each P < 0.05). In conclusion, exposure to higher PM10 levels was associated with primary pterygium, although this study observed no significant association between air pollution and overall pterygium or pterygium recurrence in Korean adults.

Purpose: The aim of this study was to evaluate the efficacy of the illuminated chopper-assisted cataract surgery in terms of shortening the surgical time and reducing the use of pupil expansion devices in eyes with iris challenges. Methods: This was a retrospective case series of a university hospital. Four hundred forty-three eyes of 433 consecutive patients who underwent illuminated chopper-assisted cataract surgery were included in this study. Cases with preoperative or intraoperative miosis, iris prolapse, and intraoperative floppy iris syndrome were included in the iris challenge group. Use of tamsulosin, iris hooks, pupil size, surgical time, and improved visibility (100/surgical time × pupil size) were compared between eyes with and without iris challenges. Mann–Whitney U test, Pearson’s Chi-square test, and Fisher’s exact test were used for statistical analysis. Results: Of 443 eyes, 66 were included in the iris challenge group (14.9%). Tamsulosin use was more common in patients with iris challenges and iris hooks were used more frequently (9.1% vs. 0%, P < 0.001) in patients with iris challenges than in those without iris challenges. Pupil size was smaller in patients with iris challenges (6.01 vs. 7.64 mm, P < 0.001). However, surgical time was not different (16.9 vs. 16.5 min, P = 0.064) between the two groups. As a result, improved visibility was calculated to be higher in patients with iris challenges (1.05 vs. 0.81, P < 0.001). Conclusion: In terms of surgical time and improved visibility, using the illuminated chopper simplified cataract surgery involving iris challenges. The use of an illuminated chopper is expected to be a good solution for challenging cataract surgeries.

Rationale:Glaucoma drainage implant surgery is a treatment option for the management of neovascular glaucoma. However, tube obstruction by blood clot after Ahmed glaucoma valve (AGV) implantation is an unpredictable clinically challenging situation.Patient concerns-diagnoses-interventions:We report 4 cases using intracameral air injection for the prevention of the tube obstruction of AGV by blood clot.Outcomes:The first case was a 57-year-old female suffering from ocular pain because of a tube obstruction with blood clot after AGV implantation in neovascular glaucoma. Surgical blood clot removal was performed. However, intractable bleeding was noted during the removal of the blood clot, and so intracameral air injection was performed to prevent a recurrent tube obstruction. After the procedure, although blood clots formed around the tube, the tube opening where air could touch remained patent. In 3 cases of neovascular glaucoma with preoperative severe intraocular hemorrhages, intracameral air injection and AGV implantation were performed simultaneously. In all 3 cases, tube openings were patent. It appears that air impeded the blood clots formation in front of the tube opening.Lessons:Intracameral air injection could be a feasible option to prevent tube obstruction of AGV implant with a blood clot in neovascular glaucoma with high risk of tube obstruction.