A record of Permian subaqueous vent activity in southeastern Brazil

The remarkable occurrence of more than 4,500 conical siliceous mounds in an area of less than 1.5 square kilometres has been reported in the Paraná basin, near Anhembi, S?o Paulo, in southeastern Brazil. These structures, which are up to two metres high, are thought to have been formed at the margin of a very shallow, broad but waning internal sea, and it was originally suggested that they are stromatolites. Yet their restricted occurrence, unusual abundance and nearly pure siliceous composition have never been satisfactorily explained by this hypothesis. Here we report field and laboratory observations on their shape, construction, composition and mineralogy. On the basis of our data we suggest that the conical mounds are the result of subaqueous Late Permian vent activity in southwestern Gondwana. The present siliceous cone field differs considerably from other Palaeozoic siliceous hot spring deposits, such as those at Rhynie, Scotland, and the Drummond basin, Australia, and therefore represents an unusual occurrence of vent activity.     

Revision of the Traumatomutilla juvenilis species group (Hymenoptera,Mutillidae)

ABSTRACT

Traumatomutilla duplicata duplicata (Gerstaecker, 1874), T. duplicata feia Casal, 1969, T. bruchi André, 1908, T. cristata (Gerstaecker, 1874), T. aterrima (Gerstaecker, 1874) and T. lorena (Cresson, 1902) are proposed as junior synonyms of Traumatomutilla bivittata (Gerstaecker, 1874). Traumatomutilla immaculiceps André, 1901, T. bivittata rubroguttata André, 1901 and T. estrella (Cresson, 1902) are proposed as junior synonyms of T. juvenilis (Gerstaecker, 1874). Traumatomutilla bispiculata (André, 1907) is proposed as a junior synonym of T. miniata (Gerstaecker, 1874). The previously unknown males of T. guarata Casal, 1969 and T. juvenilis are described and illustrated. All species of the T. juvenilis species group are redescribed and illustrated. A new species, Traumatomutilla juvenindica Bartholomay & Williams sp. nov., is described based on males and females from northern South America. Additionally, identification keys to the species and known colour forms of the T. juvenilis species group are provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:3563B9EE-A45B-4939-8436-7A808D4F8996     

Forecasting with missing data: application to coastal wave heights

This paper presents a comparative analysis of linear and mixed models for short‐term forecasting of a real data series with a high percentage of missing data. Data are the series of significant wave heights registered at regular periods of three hours by a buoy placed in the Bay of Biscay. The series is interpolated with a linear predictor which minimizes the forecast mean square error. The linear models are seasonal ARIMA models and the mixed models have a linear component and a non‐linear seasonal component. The non‐linear component is estimated by a non‐parametric regression of data versus time. Short‐term forecasts, no more than two days ahead, are of interest because they can be used by the port authorities to notify the fleet. Several models are fitted and compared by their forecasting behaviour. Copyright © 1999 John Wiley & Sons, Ltd.     

Induced pluripotent stem cell (iPS) technology: promises and challenges

In 2006, an article published in Cell by Shinya Yamanaka took by surprise the stem cell research community. By performing systematic retroviral transduction of factors enriched in embryonic stem (ES) cells, the authors demonstrated the reprogramming of mouse fibroblasts into an ES cell-like state. These cells, baptized iPS (induced pluripotent stem) cells, were immediately recognized as a ground-breaking discovery. Subsequently, the same authors and other groups reported a similar achievement with human fibroblasts. Two years later, the number of top quality papers on iPS is astonishing, and interest in the scientific community has risen to a fever pitch. But although iPS has the potential to revolutionize Regenerative Medicine, important questions still remain unanswered. Work from multiple laboratories worldwide including ours is focused on deciphering the molecular mechanisms of iPS, and trying to improve the technique to make it suitable for the clinic. In this review article we briefly discuss the past, present and future of iPS, with emphasis on urgent issues to be solved. Supported by the National Nature Science Foundation of China (Grant Nos. 30725012, 30630039 and 90813033), Knowledge Innovation Project of Chinese Academy of Sciences (Grant No. KSCX2-YW-R-48), National Key Basic Research and Development Program of China (Grant Nos. 2006CB701504, 2006CB943600, 2007CB948002, 2007CB947804. 2007CB947900) and Guangzhou Science and Technology Development Funds (Grant No. 2008A1-E4011)     

The coconut pathosystem: weed hosts of nymphs of the American palm Cixiid Haplaxius crudus (Hemiptera: Fulgoroidea)

Lethal yellowing (LY) of coconut palm (Cocos nucifera L., Arecaceae) is a disease of economic importance that is caused by the phytoplasma ‘Candidatus Phytoplasma palmae’ and is transmitted by the planthopper Haplaxius crudus (Van Duzee) (Hemiptera: Cixiidae). This study explores the weeds used by H. crudus nymphs and other Cixiidae in a coconut pathosystem in southern Mexico. Nymphs were collected directly from the root system of each weed by hand or with the help of a vacuum after carefully opening the culm. This study included 11 species of weeds: nine Poaceae [Brachiaria decumbens Stapf, B. humidicola (Rendle) Schweick, B. mutica (Forssk.) Stapf, Digitaria abyssinica (Hochst. Ex A. Rich.) Stapf, Eustachys petraea (Sw.) Desv., Leersia hexandra Sw., Panicum laxum Sw., P. maximum Jacq., Paspalum notatum Flüggé]; one Cyperaceae [Cyperus ligularis L.], and one Portulacaceae: [Portulaca pilosa L.]. Brachiaria mutica, E. petraea, B. humidicola, P. maximum were identified as the principal host species for H. crudus nymphs. Brachiaria decumbens, D. abyssinica, and C. ligularis are new host records for the nymphs of H. crudus. Additionally, it was found that H. crudus may coexist with its cogeners H. skarphion Kramer (Cixiidae) and H. caldwelli Kramer (Cixiidae), on B. mutica. On C. ligularis, H. crudus may coexist with Oecleus snowi Ball (Cixiidae) nymphs. These results suggest that in the coconut pathosystem there is a complex of multitrophic interactions that should be considered in integrated management of LY.     

Quantum financial economics — risk and returns

Financial volatility risk and its relation to a business cycle-related intrinsic time is addressed through a multiple round evolutionary quantum game equilibrium leading to turbulence and multifractal signatures in the financial returns and in the risk dynamics. The model is simulated and the results are compared with actual financial volatility data.