Patterns and bifurcations in low-Prandtl number Rayleigh-Benard convection

We present a detailed bifurcation structure and associated flow patterns for low-Prandtl number ($P=0.0002, 0.002, 0.005, 0.02$) Rayleigh-B\'{e}nard convection near its onset. We use both direct numerical simulations and a 30-mode low-dimensional model for this study. We observe that low-Prandtl number (low-P) convection exhibits similar patterns and chaos as zero-P convection \cite{pal:2009}, namely squares, asymmetric squares, oscillating asymmetric squares, relaxation oscillations, and chaos. At the onset of convection, low-P convective flows have stationary 2D rolls and associated stationary and oscillatory asymmetric squares in contrast to zero-P convection where chaos appears at the onset itself. The range of Rayleigh number for which stationary 2D rolls exist decreases rapidly with decreasing Prandtl number. Our results are in qualitative agreement with results reported earlier

A prospective randomised control trial to study the role of intra-peritoneal instillation of ropivacaine versus normal saline irrigation in reduction of post-operative pain in patients undergoing laparoscopic cholecystectomy.

The study was done to compare the effect of intra-peritoneal instillation of ropivacaine versus normal saline irrigation on post operative abdominal pain and shoulder pain in laparoscopic cholecystectomy. Ninety patients with symptomatic gall stones disease undergoing laparoscopic cholecystectomy were randomized in three groups. In study group A (n=30 patients) 0.5% of 30 ml (150 mg) of ropivacaine was instilled at gall bladder bed, and in study group B (n=30) 0.9% of 25 – 30 ml/kg of normal saline irrigation was done at gall bladder bed and sub-diaphragmatic space or control group C (n=30) none of above two intervention was done. Pain abdomen is worse during first 24 hours after laparoscopic cholecystectomy. At 6 hours pain abdomen was significantly less in group A compared to group B (p<.035). At 12 hours pain abdomen was less in group A and group B compared to control group. Intensity of shoulder tip pain was almost similar in group A and group B. Group A experienced significantly reduced shoulder tip pain at 6hours and 12 hours as compared to group C. Group B experienced less shoulder tip pain during first postoperative day as compared to control group. Intra-peritoneal instillation of ropivacaine is more effective than normal saline irrigation at early post-operative hours in reducing post-operative pain abdomen after laparoscopic cholecystectomy. However, intra-peritoneal instillation of ropivacaine and normal saline irrigation are comparable in its effect on shoulder tip pain

Coins of the Eastern Gangas ruler Anantavarman Chodaganga

Attributing the coins of the Eastern Gangas is a difficult task because the coins do not name the ruler, but only are dated in what are thought to be regnal years. Many authors in the past have tended to attribute the coins to the most prominent king of the dynasty, Anantavarman Chodaganga (1078-1147) (hereafter AC), but without any real justification. 2 In a recent paper, I proposed a method of attribution, based on the regnal lengths of the different kings, which would assign a sizable group of the known coins to the last four kings of the dynasty. 3 Coins attributable on a sound basis to AC remained unknown

Book review: Kushan, Kushano-Sasanian, and Kidarite coins: a catalogue of coins from the American Numismatic Society by David Jongeward and Joe Cribb with Peter Donovan

Accepted manuscrip

A new coin of Amyntas and some Apollophanes forgeries

Accepted manuscrip

The identity of Prakāśāditya

This presentation summarized recent research that has solved a long-standing puzzle in ancient Indian history: the identity of the king who identifies himself on the reverse of his gold coins with the epithet prakāśāditya. Most authors have assumed Prakāśāditya to be a Gupta king. In contrast, Göbl 1990 suggested on stylistic grounds that Prakāśāditya was not a Gupta at all, but a Hun. However, for reasons that are not at all clear, most authors have continued to treat Prakāśāditya as a Gupta king. In any case, Göbl was unable to establish Prakāśāditya’s identity more specifically, speculating without any real evidence that he might have been the Hun king Toramāṇa. Thus the issue of his identity was still an open question. Part of the reason for the uncertainty around the identity of Prakāśāditya is that the obverse legend on his coins had not yet been read. Gupta coins generally carry an epithet or biruda of the king on the reverse, but his name is typically revealed in the obverse legend. The parts of the legend so far read on the obverse of Prakāśāditya’s coins had not contained any parts of his real name. In Tandon 2015, in presenting the first near-complete reading of the obverse legend of the coin, I established that Prakāśāditya was in fact Toramāṇa, as Göbl had speculated