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admin — Wed, 17 Sep 2008 03:04:08 +0000

We report on the observation of new variants of metadislocations in the orthorhombic complex metallic alloy phase Al�Pd�Fe. At Fe contents above about 3 at.% we find a novel type of metadislocation in the ?-structure, which has a complementary counterpart hosted in all ?-type phases possessing phason lines as structural elements.

M. Feuerbacher aEmail:m.feuerbacher@fz-juelich.de?S. Balanetskyya?M. Heggena
[a]Institut f�r Festkrperforschung, Forschungszentrum J�lich GmbH, D-52425 J�lich, Germany

Nanoscale near-surface deformation in polymer nanocomposites

admin — Wed, 17 Sep 2008 02:23:43 +0000

The objective of the study is to understand the nanoscale near-surface deformation response of two polymer nanocomposite systems with significant differences in ductility during nanoscratching with a Berkovich indenter using a load of 1 mN and a scratch velocity of 1 ?m s?1. An accompanying objective is to investigate the commonality in surface deformation behavior between nano- and microscale deformation to reinforce the underlying fundamental principles governing surface deformation. An understanding of surface deformation response is accomplished through determination of physical and mechanical properties, structural characterization and electron microscopy analysis of surface deformation tracks and residual plastically deformed structures. The study suggests for the first time that the understanding derived from microscale surface deformation studies can be extended to nanoscale surface deformation. The microscale response in a polypropylene-based system is characterized by periodic multiple ripple-type deformation tracks that form via a mechanism identical to the periodic single-ripple-type tracks during nanoscale deformation. Similarly, in a less ductile polyethylene-based system, the periodic parabolic tracks and ironing mode of deformation during microscale deformation tend to be significantly reduced in intensity, with ironing being the primary deformation mechanism at the nanoscale. The surface deformation topography suggests that both micro- and nanoscale response is material specific. Additionally, the study suggests that reinforcement of polymers with nanoclay is a viable route to significantly decrease the susceptibility of polymeric materials to micro- and nanoscale deformation and can be discussed in terms of physical and mechanical properties of materials notably percentage crystallinity and elastic recovery.

Q. Yuana?N. Ramisettia?R.D.K. MisraaEmail:dmisra@louisiana.edu
[a]Center for Structural; Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504-4130, USA;[b]Department of Chemical Engineering, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504-4130, USA

New insights into the volume and pressure changes during the thermal cracking of oil to gas in reservoirs:Implications for the in-situ accumulation of gas cracked from oils

admin — Wed, 17 Sep 2008 01:28:25 +0000

Previous pressure-volume calculations during oil cracking to gas,based on the conventional model that presupposes oil cracking to be completed by approximately 150�C,underestimate the potential for gas accumulation in petroleum reservoirs.In this article,a compositional kinetic model of gas generation from oil cracking is suggested based on pyrolysis data using sealed gold tubes,and the pressure-volume changes are recalculated based on the new kinetic model under various geological conditions.The kinetic modeling of oil cracking confirms that crude oil begins cracking at about 160�C for a heating rate of 2�C/m.y.,and that the oil-cracking process has two distinct stages with significant differences in gas composition.The first stage is characterized by dominant C_(2-5)wet gases,whereas the second is characterized by the recracking of C_(2-5)wet gases to methane and pyrobitumen,leading to a progressive increasing dryness of the gas.The pressure-volume-temperature simulations of oil cracking to gas show that initial oil saturation,temperature-pressure gradients,and openness of reservoirs are important geological factors that control gas accumulation in original petroleum reservoirs.For a reservoir that is geologically open and saturated with 100% oil,gas spills out of the trap at 196�C.The gas loss at 240�C is almost 50% of the total gas,far lower than the 75% based on the conventional model of oil destruction.With lower oil saturation,the gas loss decreases because the gas-water contact can shift downward,and the gas loss occurs mainly by solution.For effectively isolated reservoirs,oil cracking readily exceeds lithostatic pressure,leading to reservoir fracturing,which becomes more obvious when oil saturation-decreases.The calculated fracturing temperatures for 100 and 50 vol.% oil saturations correspond to oil destructions of 95% and 86.4%,greatly exceeding the value of 1% as suggested by previous studies.A conceptual model of gas accumulation and loss in isolated and open geological conditions for a reservoir with 50% oil saturation is suggested.On the basis of this model,the Triassic carbonate gas pool in northeastern Sichuan Basin was discussed as a typical example for in-situ accumulation of gas cracked from reservoired oils.The present model infers that the reservoired oils were completely cracked into gas at 87.6 Ma,and that 75-85% of the gas has been preserved in the original reservoir rocks to form the in-situ gas pools with a huge amount of gas resources.We believe that gas accumulation from oil cracking in original petroleum reservoirs is much more prospective than previously thought,and that gas cracked from oil has great potential in other areas of the Sichuan Basin and the eastern Tarim Basin.

Hui Tian?Xianming Xiao?Ronald W.T.Wilkins

NO ESCAPE FROM SCIENCE

admin — Wed, 17 Sep 2008 00:21:38 +0000

Scientific evidence can make or break a case, and experts can help juries understand what it all means. But first, lawyers need to persuade the judicial gatekeepers that an expert’s testimony is relevant and reliable. Here is help on meeting the tough admissibility standards for evidence.

William C. Smith

New generation drinking: The uncertain boundaries of criminal enterprise in modern Kenya

admin — Mon, 23 Jun 2008 00:24:46 +0000

During the 1990s, a new kind of alcoholic beverage began to appear in Kenyan bars. The ‘new generation’ drinks, as they came to be known, disturbed an established boundary between the formal and informal sectors, and between legitimate enterprise and criminal endeavour. They invaded the formal spaces of licit drinking, finding their way on to the shelves of bars between the bottles of Tusker and Bond 7; they shamelessly appropriated the physical markers of respectable business, with labelled bottles and advertising. And they were cheap, since they avoided the burden of taxation which had pushed lager beer and whisky beyond the financial reach of many drinkers. Within a year or two, these brash new imitators had captured a considerable chunk of the drinking market. In campaigning against them, the formal drinks industry — already engaged in an internecine ‘beer war’ of its own — argued that the ‘new generation’ drinks were an active and direct danger to public health. In this the industry has, more than once, received the support of vocal sections of the populace and the press, enraged by a series of tragic poisonings associated with illicit beverages. But the ‘new generation’ drinks have not disappeared, nor has their production been prevented, even though some are made on an industrial scale in premises whose locations are well known (and, indeed, are advertised). Conflicting statements emerge from different organs of the state regarding the legality, and safety, of these beverages; bans are announced, and forgotten, and announced again: and the drinks continue to be sold. This article explores the origins of the ‘new generation’ drinks, and what their continued availability tells us about the definition of crime in modern Kenya.

Justin Willis

Napoleon Dynamite:Asperger’s disorder or Geek NOS?

admin — Sun, 13 Apr 2008 03:49:43 +0000

Napoleon Dynamite, the quirky hit film from 2004, is a fascinating portrayal of a teenager with social difficulties. The character Napoleon provokes intriguing diagnostic questions in distinguishing between mental illness and the spectrum of normal behavior. He demonstrates several symptoms of Asperger’s disorder, yet he also challenges the notion that children and adolescents with Asperger’s spectrum disorders will not be accepted or understood. He forms genuine, connected friendships, and fans of the movie appear to celebrate his quirkiness rather than ridicule his oddities. The authors explore the extent to which cultural issues have an impact on psychiatric phenomenology, as well as the potential treatment issues for someone with his apparent social challenges. Finally, the authors offer possible explanations for Napoleon’s immense popularity, especially among adolescents. With the rise of computer technology, our culture has fully embraced the idea of what has come to be called “geekdom,” and the authors consider the idea that Napoleon’s popularity may be a more rural equivalent for this phenomenon. The success of the movie appears to be related to a genuine celebration of Napoleon himself.

Levin HW　Schlozman S

***Issue 5

New data on straggled eyeworm Oxyspirura chabaudi (Barus, 1965) (Nematoda,Thelaziidae) in Europe

admin — Sun, 13 Apr 2008 03:22:01 +0000

Three male specimens of the eyeworm, Oxyspirura chabaudi, were found duringthe post mortem examination of one individual of Turdus merula L. (Passeriformes). This is the firstrecord of Turdus merula as a host for O. chabaudi.

Okulewicz, A　Okulewicz, J　Hildebrand, J　Zalesny, G
Univ Wroclaw, Inst Genet and Microbiol, Dept Parasitol, PL-51148 Wroclaw,Poland; Med Acad Wroclaw, Dept Gen Biol and Med Parasitol, PL-50368 Wroclaw, Poland

Nematoda　 Oxyspirura chabaudi　 Passeriformes Turdus merula Poland

New feather mite species (Acari, Astigmata) from the Sulphur-crested CockatooCacatua galerita and Yellow-crested Cockatoo C-sulphurea (Psittaciformes, Cacatuidae)

admin — Sun, 13 Apr 2008 03:14:17 +0000

Two new genera and three new species of feather mites (Astigmata,Pterolichoidea, Analgoidea) are described from two closely related species of cockatoos, Cacatuagalerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen.nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualgesmicrodiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on thesetwo species of parrots points to a very close affinity of Cacatua sulphurea and C. galerita andgives additional support for the recent hypothesis of the conspecificity of these birds.

Dabert, J　Badek, A　Skoracki, M
Adam Mickiewicz Univ Poznan, Dept Anim Morphol, PL-61614 Poznan, Poland

Feather mites　 new taxa　 host-parasite relationships　 Cacatuidae　 GENERICGROUP ASTIGMATA　 PARROTS AVES　 PTEROLICHIDAE　 PSITTACIDAE　 GAUD TAXA GEN.

Neuroendocrine small cell carcinoma of the cervix associated withendocervical adenocarcinoma:a case report

admin — Sun, 13 Apr 2008 02:21:19 +0000

BACKGROUND: Small-cell carcinoma (SCC) of the cervix is an uncommon member ofthe neuroendocrine group of cervical carcinomas that is frequently intermixed with a non-SCCcomponent in the form of an adenocarcinoma (ADC) or squamous carcinoma. CASE: Colposcopy revealed acervical mass in a 41-year-old woman and a Pap smear the presence of some tumor cells from SCC,which was confirmed by subsequent biopsy. The patient received 3 cycles of chemotherapy and thenunderwent major surgery. The cervical samples showed areas of endocervical ADC adjacent to andintermixed with the SCC. Reviewing the Pap smear, a previously missed malignancy was recognized. Onsubsequent molecular investigation to assess clonality by microsatellite analysis, the presence ofHR-HPV DNA18 on real-time polymerase chain reaction, p16(INK4a) fluorescence in situ hybridizationstatus and the corresponding immunohistochemical expression supported the hypothesis that the twocomponents of the tumor shared the same cell origin. CONCLUSION: SCC of the cervix is a rare butdistinct HR-HPV-18-related cervical carcinoma often intermixed with a clonally related non-smallcell component consisting of an ADC or squamous carcinoma. The presence of SCC tumor cells in acervical smear should prompt a search for malignant glandular or squamous tumor cells.

Alphandery,C　Dagrada,G　Frattini,M　Perrone,F　Pilotti,S
Department of Pathology and Experimental Molecular Pathology, IstitutoNazionale per lo Studio e la Cura dei Tumori, Milan, Italy.

stratum corneum chymotryptic enzyme　 Neoplasms　 Cervical Smears Carcinoma

Neuroendocrine small cell carcinoma of the cervix associated withendocervical adenocarcinoma: a case report

admin — Sun, 13 Apr 2008 02:19:14 +0000

Alphandery,C　Dagrada,G　Frattini,M　Perrone,F　Pilotti,S
Department of Pathology and Experimental Molecular Pathology, IstitutoNazionale per lo Studio e la Cura dei Tumori, Milan, Italy.

stratum corneum chymotryptic enzyme　 Neoplasms　 Cervical Smears Carcinoma