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This paper describes some of the major contributions to metrology and physics made by the NIST Electricity Division, which has existed since 1901. It was one of the six original […]

The 10 V Josephson voltage standard (JVS) systems of the National institute of Standards and Technology (NIST) and the Sandia National Laboratories (SNL) were compared by two different methods Used simultaneously. The first method uses the well-established technique of the NIST's Measurement Assurance Program (MAP) in which Zener-diode electronic voltage standards (often called Zener voltage standards) are used as traveling standards. The second method, reported here for the first time, used a recently developed portable JVS as the traveling standard. This method provides a thorough verification of a JVS system including all the components of hardware and software as they are used normally to calibrate a secondary voltage standard. The uncertainty of the second method was more than an order of magnitude smaller and provided a way to evaluate the uncertainty associated with the predictability of Zeners when used as traveling standards. [ABSTRACT FROM AUTHOR]

Aim: To report the outcomes of penetrating canaloplasty for corticosteroid-induced glaucoma in a case series., Methods: Penetrating canaloplasty is a bleb-independent filtering surgery unifying canaloplasty and trabeculectomy. In this study, the surgery was performed to restore the natural outflow through surgically expanded Schlemm's canal and generated trabeculum ostium. A total of 10 eyes of 8 patients were treated with penetrating canaloplasty for corticosteroid-induced glaucoma. Intraocular pressure (IOP) and the number of glaucoma medications at postoperative 3, 6, 12, 18, 24, 36, and 48mo were documented as primary endpoint. Complications after the surgery were recorded as secondary endpoint., Results: Penetrating canaloplasty was accomplished successfully for all 10 eyes, with a mean follow-up of 20.4±13.0mo (range 6-48mo). The mean preoperative IOP and number of anti-glaucoma medications were 45.1±6.5 mm Hg and 3.3±0.5 respectively. The mean post-operative IOP at 3, 6, 12, 18, 24, 36, and 48mo were 15.8±6.0, 14.7±3.3, 15.3±2.0, 15.6±2.6, 17.5±1.8, 16.5±4.9, and 14.0 mm Hg. The number of anti-glaucoma medications at these time points were all 0. This surgery failed to control the IOP in 1 eye at 1mo after surgery. Hyphaema occurred in 3 eyes on the first day after surgery. Postoperative transient IOP increasing was encountered with in two eyes from 1wk to 1mo after surgery. Choroidal detachment developed in one eye but responded well to conservative treatment., Conclusion: Penetrating canaloplasty is effective for corticosteroid-induced glaucoma without serious complications, making it a viable or preferred alternative option., (International Journal of Ophthalmology Press.)

Purpose: To determine the correlation between superior limbic keratoconjunctivitis (SLK) and selected tear cytokines and to evaluate the efficacy of these cytokines in monitoring the response of patients with SLK to either medical treatment alone or in combination with conjunctival resection., Design: A cohort study., Methods: Twenty-five eyes of 13 patients with SLK were assigned to either medically responsive or surgical treatment groups depending on their responses 1 month after initial medical treatment. Treatment efficacy was assessed by improvements in clinical grading and decreases in the levels of tear cytokines., Results: Fourteen eyes were improved by medical treatment alone, whereas satisfactory outcomes were achieved for the remaining 11 eyes after surgical management. The overall grading prior to medical treatment was lower in medically responsive group compared with surgical treatment group (p=0.0139). Among the examined tear cytokines, monocyte chemoattractant protein (MCP)-1 was positively associated with the severity of clinical grading (p=0.0251). While both treatments significantly decreased the levels of MCP-1 and interleukin-6, surgical treatment also decreased the levels of interferon-γ and tumour necrosis factor-α. Notably, overall cytokine levels after surgical treatment were lower than those after medical treatment alone., Conclusions: Since an association of tear MCP-1 level with the clinical grading and treatment response of SLK was observed in this study, tear MCP-1 may be a potential indicator of SLK disease severity. According to the degree to which the tear cytokine levels were decreased, surgical treatment appears to be an effective treatment modality for patients with SLK who are refractory to medical treatment alone., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)