The tensor force is implemented into the mean-field model so that the evolution of nuclear shells can be described for exotic nuclei as well as stable ones. Besides the tensor-force part simulating the meson exchange, the model is an extension of the successful Gogny model. One of the major issues of rareisotope beam physics is a reduced spin-orbit splitting in neutron-rich exotic nuclei. It will be shown that the effect of the tensor force on this splitting is larger than or about equal to the one due to the neutron skin. We will present predictions for stable and exotic nuclei with comparisons to conventional results and experimental data. DOI: 10.1103/PhysRevLett.97.162501 PACS numbers: 21.60.ÿn, 21.10.Pc, 21.30.Fe Like other many-body quantal systems, the mean field governs largely the structure of nuclei. Recently it has been shown, by using the shell model, that the tensor force has a specific, robust, and systematic effect on the single-particle energies of nuclei, even breaking or creating magic numbers in some cases [1]. It is then very interesting to explore what can be seen by including the tensor force into the mean-field calculations. Note that in the shell model, the single-particle wave functions are given a priori and are fixed more or less.The existing successful and systematic mean-field calculations are either of Skyrme-type [2,3] or of Gogny-type [4]. In the former, the interaction is of zero-range nature with derivative couplings, while the tensor terms have been suppressed, probably because the number of free parameters is made as small as possible [5]. In the latter, the interaction is of finite-range nature [4,6,7], while there is no tensor term either.In this Letter, we present a new mean-field model which includes the tensor force explicitly and keeps the merits of the existing models. In exotic nuclei far from stability with large asymmetric ratios between the proton number (Z) and the neutron number (N), the single-particle properties may show distinct characteristic changes from those seen in usual stable nuclei. In particular, in neutron-rich exotic nuclei, the neutron skin can be created [8], which may give rise to a diffuse surface resulting in a reduced spin-orbit splitting [9,10]. The tensor force changes the spin-orbit splitting in a systematic and different way [1]. It should be very important to investigate the neutron-skin effect and the tensor-force effect within a single framework.We introduce a new Gogny-type mean-field model, called GT2. All the terms of the Gogny interaction are kept, while their strength parameters are readjusted. The Gogny interaction contains central interactions with Gaussian-function dependences on the relative distance of nucleons [4,6,7]. Two ranges of Gaussians are included with full four spin-isospin coupling terms, ending up with eight terms. The tensor term is expressed as [1],where 1;2 (s 1;2 ) denotes the isospin (spin) of nucleons 1 and 2, K means the coupling of two operators in the brackets to an angular momentum (or rank) K, and Y d...

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Human strongyloidiasis is a parasitic infection induced by the nematode Strongyloides stercoralis which can cause gastrointestinal disturbances. It is believed to be a zoonosis with a potential for cross infection between humans and dogs. The aim of this work was to study this cross infection. Epidemiological surveys of human intestinal parasites were carried out using direct smears and cultures in the Amami Islands during the summer season from 2003 to 2008. Stools were collected from people and dogs inhabiting the Amami Islands, i.e., Kikai, Amami, Kakeroma, Uke, Yoro and Okinoerabu, Japan. It was confirmed that the infective ratio of Strongyloides was 2.8% of 660 residents studied and 10.0% of their 55 dogs. The owners who had parasite-carrier dogs were not found to have parasites, and, conversely the dogs who were kept by owners having parasites were free of parasites. The epidemiological results of the present study demonstrate that natural infection of Strongyloides does not occur between humans and dogs.

Ciguatoxins CTXs responsible for ciguatera fish poisoning CFP in Amami Islands, Kagoshima, Japan in 2008 were determined by LC-MS/MS analysis. Ciguatoxin-1B CTX1B , 54-deoxyCTX1B, and 52-epi-54-deoxyCTX1B were detected in Variola louti and Lutjanus monostigma. The toxin profile distinctly differed from that of a CFP-related fish from Miyazaki, which mainly contained ciguatoxin-3C type toxins. Toxin profiles were species-specific, as observed in fish from Okinawa. The LC-MS/MS and mouse bioassay MBA methods produced comparable data, though 54-deoxyCTX1B was not taken into consideration owing to the lack of toxicity data. To improve assessment, toxicity data for this compound are needed. A reef fish caught on the same occasion and judged nontoxic by MBA 0.025 MU/g was found to contain low levels of CTX, indicating a potential risk for CFP.

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LiNO, addition to the cement solidified miscellaneous wastes has been proposed for preventing hydrogen ges generation caused by the corrosion of aluminum materials contained in the wastes. To determine an additive among alkaline metal ions, galvanic current was measured in 0.1 M alkaline metal hydroxide solution between aluminum and platinum electrodes. The volume of hydrogen gas generated from an aluminum specimen was measured in a KOH solution with LiN03, LiCI, LiBr, Li2C03 or Li2S04 to decide the best additive. Applicability of the chosen additive to cement was confirmed by hydrogen gas generation measurement from an aluminum specimen in cement paste. The prevention mechanism was analyzed by X-ray diffraction, SEM and SIMS. The current measured in LiOH solution decreased with time, then reached 0 pA/mmz, while the current was detected in other alkaline metal hydroxide solutions. The least volume of hydrogen gas generation was measured in a KOH solution with LiN03. The volume of generated hydrogen gas in cement paste with LiN03 was less than 10% of that without LiNO,. The results of analyses showed that a n insoluble film of LiH(A10z)z5Hz0 was formed on the aluminum surface. 'These results suggested that LiNOs addition to cement is effective to prevent hydrogn gas generation by formation of the insoluble film on aluminum.

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