Models of cultural evolution often link the need for leadership in warfare or communal projects with the development of social differentiation. Yet when we compare indicators of warfare, large construction projects, and social differentiation for three archaeological cultures in the Osmore drainage of southern Peru, a very different pattern emerges. This counter-intuitive example highlights a p...

Recently reported summertime methane (CH4) emissions (6.7 +/- 13.3 mg CH4/(m2 x hr)) from newly created marshes in the drawdown area of the Three Gorges Reservoir (TGR), China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and g...

INTRODUCTION In spite of the progress in diagnosis and therapeutic options, esophageal perforation resulting in mediastinitis is a very serious condition with a high morbidity. AIM To evaluate the use of esophageal stents for the treatment of patients suffering from mediastinitis. MATERIAL AND METHODS Retrospective (2008-2012) analysis of a group of patients requiring surgical treatment. Th...

BACKGROUND The aim of this study was to evaluate the feasibility of single-port video-assisted thoracic surgery (VATS) in the treatment of secondary spontaneous pneumothorax (SSP). METHODS Twenty-four patients who were scheduled to undergo single-port VATS for SSP were studied. The medical records of the patients were retrospectively reviewed. The mean follow-up duration was 26.1±19.8 months....

ABSTRUCT The authors prepared the obstructive jaundice model on which the external biliary drainage was operable, and tried to clarify the critical duration of obstruction from the aspects of the standard liver function and hepatic fibrosis, and the following results were obtained. 1) The T. B, Al-p, GOT and GPT levels in 1 to 4 weeks after the common bile duct obstruction was significantly hig...

UNLABELLED The aim of the study was to determine whether patients treated with anticoagulants in the perioperative period are at higher risk of developing bleeding complications. MATERIAL AND METHODS Medical records of patients operated for abdominal hernia were analysed. Data concerning demographic characteristic of a group, type of hernia, comorbidities, preoperative anticoagulation therapy...

Here it is shown that chaotic oscillations can appear after a series of period doublings in radiating diffusion flames when the activation temperature is high enough. It is also shown that period doubling cascades appear typically in very small regions and that they may not be observable if one starts with small perturbations of a steady flame.

We prove that the period doubling operator has an expanding di rection at the xed point We use the induced operator a Perron Frobenius type operator to study the linearization of the period dou bling operator at its xed point We then use a sequence of linear operators with nite ranks to study this induced operator The proof is constructive One can calculate the expanding direction and the rate ...

We show that the greedy spanner algorithm constructs a (1+ )-spanner of weight −O(d)w(MST) for a point set in metrics of doubling dimension d, resolving an open problem posed by Gottlieb [11]. Our result generalizes the result by Narasimhan and Smid [15] who showed that a point set in d-dimension Euclidean space has a (1+ )-spanner of weight at most −O(d)w(MST). Our proof only uses the packing ...