Redshift distributions of galaxies in the Dark Energy Survey Science Verification shear catalogue and implications for weak lensing

We present photometric redshift estimates for galaxies used in the weak lensing analysis of the Dark Energy Survey Science Verification (DES SV) data. Four model- or machine learning-based photometric redshift methods -- ANNZ2, BPZ calibrated against BCC-Ufig simulations, SkyNet, and TPZ -- are analysed. For training, calibration, and testing of these methods, we construct a catalogue of spectroscopically confirmed galaxies matched against DES SV data. The performance of the methods is evaluated against the matched spectroscopic catalogue, focusing on metrics relevant for weak lensing analyses, with additional validation against COSMOS photo-zs. From the galaxies in the DES SV shear catalogue, which have mean redshift $0.72\pm0.01$ over the range $0.3<z<1.3$, we construct three tomographic bins with means of $z=\{0.45, 0.67, 1.00\}$. These bins each have systematic uncertainties $\delta z \lesssim 0.05$ in the mean of the fiducial SkyNet photo-z $n(z)$. We propagate the errors in the redshift distributions through to their impact on cosmological parameters estimated with cosmic shear, and find that they cause shifts in the value of $\sigma_8$ of approx. 3%. This shift is within the one sigma statistical errors on $\sigma_8$ for the DES SV shear catalog. We further study the potential impact of systematic differences on the critical surface density, $\Sigma_{\mathrm{crit}}$, finding levels of bias safely less than the statistical power of DES SV data. We recommend a final Gaussian prior for the photo-z bias in the mean of $n(z)$ of width $0.05$ for each of the three tomographic bins, and show that this is a sufficient bias model for the corresponding cosmology analysis.Comment: high-resolution versions of figures can be downloaded from http://deswl.github.i

Linear Darier's disease: A case with bilateral presentation

Darier's disease is an autosomal dominant genodermatosis characterized by a persistent eruption of hyperkeratotic greasy papules mainly over the seborrheic sites of the body, usually associated with nail abnormalities and sometimes with mucous membrane lesions. The lesions typically occur in the younger age group and are associated with pruritus. We report here an atypical case of Linear Darier's disease with bilateral presentation in a middle-aged adult that could be confused with conditions such as lichen planus, inflammatory linear verrucous epidermal nevus, and wart

Prevalence of pediatric eye diseases in Assam, India — a hospital-based retrospective data

Background: In a hospital setting, paediatric eye disease manifests itself in a complex network. It is essential to comprehend the scope of many common eye disorders in order to develop new evidence-based strategies for mitigating such disorders. The study aimed to investigate the hospital-based prevalence of pediatric ocular disorders of patients attending a tertiary eye care hospital. Material and methods: A three-year data from 2017–19 were extracted from the electronic medical records of Chandraprabha Eye Hospital, Assam, India. Refining the data was further carried out using the age criteria up to 18 years. The diagnosis for all the study subjects was taken into consideration and was further analyzed. The inclusion criteria included subjects within the range of 0–18 years reporting to the hospital during the study period. Subjects diagnosed with non-ocular problems, incomplete ophthalmological assessments, and those aged more than 18 years were excluded. Results: A total of 11807 relevant medical records were reviewed. Among the study subjects, 58.52% (n = 6910) were males. The mean (SD) age was 11.9 (4.8) years. Of the subjects 21.28% (n = 2513) were in age group 0–5 years, 42.39% (n = 5006) — in 6–11 years, and 36.31% (n = 4288) in 12–18 years. A total number of 152 pediatric ocular abnormalities were identified from the reviewed files. Myopia alone accounted for 19% of all, followed by vernal keratoconjunctivitis with 14.7%, followed by asthenopic presentation associated with non-strabismic binocular vision anomalies (7.4%), congenital nasolacrimal duct obstruction (2.9%), amblyopia (2.8%), and ocular injuries (2.7%). Conclusions: Refractive errors, allergic conjunctivitis, ocular injuries, amblyopia and squint, uveitis, congenital cataract, and non-strabismic binocular vision anomalies were identified as the most common pediatric ocular abnormalities seen in routine clinical practice, laying the groundwork for a standard protocol to evaluate and assess visual function in any case of pediatric anomaly.

Ocular dirofilariasis

Dirofilaria is a parasite of domestic and wild animals that can infect humans accidentally. It is being reported in increasing numbers from Mediterranean countries like Italy. In India this infection is occasionally being reported. We report three cases of ocular dirofilariasis from the state of Assam presenting as periorbital and subconjunctival cysts. The parasites were identified as Dirofilaria repens. The purpose of this article is to take note of this emerging zoonosis in Assam; also to review literature in the cases reported