Anthropogenic intensification of short-duration rainfall extremes

Short- duration (1-3 h) rainfall extremes can cause serious damage to societies through rapidly developing (flash) flooding and are determined by complex, multifaceted processes that are altering as Earth's climate warms. In this Review, we examine evidence from observational, theoretical and modelling studies for the intensification of these rainfall extremes, the drivers and the impact on flash flooding. Both short- duration and long- duration (\textgreater1 day) rainfall extremes are intensifying with warming at a rate consistent with the increase in atmospheric moisture (~7% K-1), while in some regions, increases in short- duration extreme rainfall intensities are stronger than expected from moisture increases alone. These stronger local increases are related to feedbacks in convective clouds, but their exact role is uncertain because of the very small scales involved. Future extreme rainfall intensification is also modulated by changes to temperature stratification and large- scale atmospheric circulation. The latter remains a major source of uncertainty. Intensification of short- duration extremes has likely increased the incidence of flash flooding at local scales and this can further compound with an increase in storm spatial footprint to considerably increase total event rainfall. These findings call for urgent climate change adaptation measures to manage increasing flood risks

Efficacy of endometrial aspiration cytology in diagnosis of endometrial pathologies in a tertiary care centre

Introduction: Endometrial pathologies contribute significantly to increased morbidity and mortality in females, and still tend to remain undiagnosed till later stages. Endometrial cytology is one of the most powerful and reliable investigations in detection of various endometrial pathologies, including hyperplasia, malignancies and can be used as an early evaluative modality on routine basis.Objectives: The present study was aimed at assessing the diagnostic efficacy of endometrial aspirate cytology in the diagnosis of various endometrial pathologies in terms of accuracy, sensitivity and specificity etc., considering histopathology as standard . It also involved the study of various morphological patterns ranging across the spectrum of endometrial pathology by aspiration cytology .Material and methods: Using Karmann’s cannula, endometrial aspirate sample was obtained in 106 patients from gynaecology out-patient department and the smears were stained using papanicolaou stain. The findings of cytology were correlated with histopathology.Results: The present study comprises 106 patients. 102 out of 106 samples for cytology were adequate with an overall diagnostic accuracy of 95.1% , a sensitivity of 93.2%, specificity of 97.7%, with 98.2% positive predictive value and 91.3% negative predictive value.Conclusion: Endometrial aspiration cytology is an easy to perform, minimally invasive, safe and cheaper procedure for diagnosing endometrial pathologies. Its results are fairly acceptable with good cyto-histopathological correlation and hence can be used for screening of endometrial pathologies and malignancies

Utilization of ferrous leach liquor to synthesize gamma ferric oxide

The production of pigment grade titanium dioxide involves leaching of ilmenite with acids that also results in the formation of ferrous sulfate/chloride. Usually the ferrous salts are spray-roasted to regenerate the sulfuric acid/hydrochloric acid for recycling. However, the quantities of ferrous leach liquor and the capital cost of the regeneration plant dictate the viability of regeneration of acids, In the case of smaller ilmenite processing plants, the regeneration of the acid is not economical and warrants alternate methods of using the ferrous leach liquor, The present paper describes a novel method of synthesizing gamma ferric oxide from ferrous leach liquor obtained from a titanium dioxide pigment plant situated in south India. The partial precipitation technique is employed to purify the ferrous leach liquor and make it suitable for the synthesis. Sodium carbonate is used to precipitate iron as ferrous carbonate and is directly calcined to yield gamma ferric oxide. Experiments were conducted to study the effect of heating rate, condition of the precipitate, whether dry or wet, and extent of oxidation of ferrous on the magnetic properties such as coercivity and specific magnetization. Cobalt-doped gamma ferric oxide was also prepared by the carbonate precipitation route