Image restoration for three-dimensional fluorescence microscopy using an orthonormal basis for efficient representation of depth-variant point-spread functions

A depth-variant (DV) image restoration algorithm for wide field fluorescence microscopy, using an orthonormal basis decomposition of DV point-spread functions (PSFs), is investigated in this study. The efficient PSF representation is based on a previously developed principal component analysis (PCA), which is computationally intensive. We present an approach developed to reduce the number of DV PSFs required for the PCA computation, thereby making the PCA-based approach computationally tractable for thick samples. Restoration results from both synthetic and experimental images show consistency and that the proposed algorithm addresses efficiently depth-induced aberration using a small number of principal components. Comparison of the PCA-based algorithm with a previously-developed strata-based DV restoration algorithm demonstrates that the proposed method improves performance by 50% in terms of accuracy and simultaneously reduces the processing time by 64% using comparable computational resources.OCIS codes: (110.0110) Imaging systems, (110.0180) Microscopy, (100.6890) Three-dimensional image processing, (170.3010) Image reconstruction techniques, (220.1000) Aberration compensation     

Lack of impact of a water and sanitation intervention on the nutritional status of children in rural Bangladesh

The nutritional impact of a water and sanitation intervention in a rural community of Bangladesh, comprising the provision of handpumps, construction of latrines and hygiene education was assessed. During 3 years, the quarterly anthropometric measures of about 200 children aged 12-35 months from the intervention community were compared with those of a similar number of children from a control area. The interventions reduced the incidence of diarrhoea by 25 per cent among the children less than 5 years of age. There was no significant difference in nutritional status, however, between the two groups of children. Moreover, within the intervention area, indicators of water and latrine use were not significantly related to the children's nutritional status. This suggests that either the obtained reduction of diarrhoea was not large enough to have an impact on nutritional status or that diarrhoea is not an important cause of malnutrition in this community.     

Tubewell water consumption and its determinants in a rural area of Bangladesh

As part of the evaluation of a water supply, sanitation and hygiene education project in rural Bangladesh, the consumption of water from the improved supplies was estimated from an observational study. Women volunteers observed and recorded all water collection activities of each group of households using a handpump over a 2-day period. Data from questionnaire surveys on household characteristics were related to per capita use of water. The mean household water consumption rate was 43 l per capita per day. Univariate analyses showed that several factors were significantly associated with water consumption, including family size and age structure, occupation, distance from the house to the handpump, the number of people served by a handpump, and possession of luxury items. Multiple regression analysis showed that several factors remained associated with per capita consumption, although their predictive value was low. The method of measuring water consumption, and the policy implications of the findings, are discussed.     

Osteopetrosis

A 15 years old Bangladeshi boy presented with hepatosplenomegaly, anaemia, multiple fractures (symptomatic and asymptomatic) without jaundice was investigated. Laboratory findings revealed leukoerythroblastic blood picture with reduced haemoglobin (7.7 gm/dl). Skeletal survey showed generalized increased bone density, sclerosed medulary space, Rugger-Jersey spine and diploic space filled with dense materials. Overlapping clinical features of both intermediate autosomal recessive and adult autosomal dominant variety of osteopetrosis were found in this patient but diagnosis were made on the basis of typical radiological finding which was mostly consistent with the adult autosomal dominant variety. The patient was treated conservatively and specialist consultation was taken in managing bony abnormalities. This patient was discharged with advised of subsequent follow-up.     

Arsenic Exposure from Drinking Water and QT-Interval Prolongation: Results from the Health Effects of Arsenic Longitudinal Study

Background: Arsenic exposure from drinking water has been associated with heart disease; however, underlying mechanisms are uncertain.Objective: We evaluated the association between a history of arsenic exposure from drinking water and the prolongation of heart rate–corrected QT (QTc), PR, and QRS intervals.Method: We conducted a study of 1,715 participants enrolled at baseline from the Health Effects of Arsenic Longitudinal Study. We assessed the relationship of arsenic exposure in well water and urine samples at baseline with parameters of electrocardiogram (ECG) performed during 2005–2010, 5.9 years on average since baseline.Results: The adjusted odds ratio (OR) for QTc prolongation, defined as a QTc ≥ 450 msec in men and ≥ 460 msec in women, was 1.17 (95% CI: 1.01, 1.35) for a 1-SD increase in well-water arsenic (108.7 µg/L). The positive association appeared to be limited to women, with adjusted ORs of 1.24 (95% CI: 1.05, 1.47) and 1.24 (95% CI: 1.01, 1.53) for a 1-SD increase in baseline well-water and urinary arsenic, respectively, compared with 0.99 (95% CI: 0.73, 1.33) and 0.86 (95% CI: 0.49, 1.51) in men. There were no apparent associations of baseline well-water arsenic or urinary arsenic with PR or QRS prolongation in women or men.Conclusions: Long-term arsenic exposure from drinking water (average 95 µg/L; range, 0.1–790 µg/L) was associated with subsequent QT-interval prolongation in women. Future longitudinal studies with repeated ECG measurements would be valuable in assessing the influence of changes in exposure.     

Morphometric and Meristic Characteristics and Some Aspects of Reproductive Biology of Spiny Eel,Mastacembelus armatus (Lacepede, 1800)

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Various body measurements of spiny eel, Mastacembelus armatus (Lacepede, 1800) were positively correlated...