Nuclear liquid-gas phase transition studied with antisymmetrized molecular dynamics

The nuclear liquid-gas phase transition of the system in ideal thermal equilibrium is studied with antisymmetrized molecular dynamics. The time evolution of a many-nucleon system confined in a container is solved for a long time to get a microcanonical ensemble of a given energy and volume. The temperature and the pressure are extracted from this ensemble and the caloric curves are constructed. The present work is the first time that a microscopic dynamical model which describes nuclear multifragmentation reactions well is directly applied to get the nuclear caloric curve. The obtained constant pressure caloric curves clearly show the characteristic feature of the liquid-gas phase transition, namely negative heat capacity (backbending), which is expected for the phase transition in finite systems.Comment: 31 pages, 8 figures, added formalism details, several improvements and new results, submitted to Phys. Rev.

Relevance of equilibrium in multifragmentation

The relevance of equilibrium in a multifragmentation reaction of very central $^{40}Ca+^{40}Ca$ collisions at 35 MeV/nucleon is investigated by using simulations of Antisymmetrized Molecular Dynamics (AMD). Two types of ensembles are compared. One is the reaction ensemble of the states at each reaction time $t$ in collision events simulated by AMD, and the other is the equilibrium ensemble prepared by solving the AMD equation of motion for a many-nucleon system confined in a container for a long time. The comparison of the ensembles is performed for the fragment charge distribution and the excitation energies. Our calculations show that there exists an equilibrium ensemble which well reproduces the reaction ensemble at each reaction time $t$ for the investigated period $80\leq t\leq300$ fm/$c$. However, there are some other observables which show discrepancies between the reaction and equilibrium ensembles. These may be interpreted as dynamical effects in the reaction. The usual static equilibrium at each instant is not realized since any equilibrium ensemble with the same volume as that of the reaction system cannot reproduce the fragment observables.Comment: 13 pages and 12figures; added a few sentences and corrected typos, accepted in Phys. Rev.

Development of a UV-transparent Lens Array for Enlarging the Effective Area of Multichannel SiPMs

We developed a UV-transparent lens array that can increase the photon detection efficiency of a silicon photomultiplier (SiPM) array comprising of 64 pixels ($3\times3$ mm$^2$ each) and 0.2-mm gaps. Through the plano-convex spherical lens on each $3.2\times3.2$ mm$^2$ region, we showed that the loss of photon detection efficiency due to the pixel gaps could be recovered as the incident photons get concentrated on the sensitive regions of the SiPM array. By using a prototype lens array, we achieved approximately 10%-30% relative increase in photon detection efficiency in our target angles of incidence of 30-60 deg.Comment: Accepted for publication in the Proceedings of the 5th International Workshop on New Photon-Detectors (PD18

Development and photo-responsive peptide bond cleavage reaction of two-photon near-infrared excitation-responsive peptide

Two-photon near-infrared excitation-responsive amino acid was developed. It was incorporated into a peptide, and focused near-infrared pulsed laser irradiation-induced peptide bond cleavage reaction at the C-terminal position of the photo-responsive amino acid was observed

A Descending Circuit Derived From the Superior Colliculus Modulates Vibrissal Movements

The superior colliculus (SC) is an essential structure for the control of eye movements. In rodents, the SC is also considered to play an important role in whisking behavior, in which animals actively move their vibrissae (mechanosensors) to gather tactile information about the space around them during exploration. We investigated how the SC contributes to vibrissal movement control. We found that when the SC was unilaterally lesioned, the resting position of the vibrissae shifted backward on the side contralateral to the lesion. The unilateral SC lesion also induced an increase in the whisking amplitude on the contralateral side. To explore the anatomical basis for SC involvement in vibrissal movement control, we then quantitatively evaluated axonal projections from the SC to the brainstem using neuronal labeling with a virus vector. Neurons of the SC mainly sent axons to the contralateral side in the lower brainstem. We found that the facial nucleus received input directly from the SC, and that the descending projections from the SC also reached the intermediate reticular formation and pre-Bötzinger complex, which are both considered to contain neural oscillators generating rhythmic movements of the vibrissae. Together, these results indicate the existence of a neural circuit in which the SC modulates vibrissal movements mainly on the contralateral side, via direct connections to motoneurons, and via indirect connections including the central pattern generators

Pengaruh Penyuluhan Obat Terhadap Peningkatan Perilaku Pengobatan Sendiri Di Kabupaten Banyumas

Self-medication is the mostly effort to coped health complaint, therefore to drug consume decrease unsuitable, it needed safety socialization to self-medication. The study was take to analyze the effect of drug counseling to self-medication increase in Banyumas regency. In addition to analyze the method effectiveness used in drug counseling to self-medication act. The instrument research used questionnaires in this study and purposive sampling used to took the sample. The respondents were 192 residents whom live in Banyumas regency. The type of research quasi-experimental with non-equivalent control group pretest and posttest research design. The data then analyzed by dependent-sampel t-test to find the effect of counseling to self-medication behavior in α = 0.05. While to find the effectiveness of between discussion group and lecture method by leaflet used independen-sampel t-test in α = 0.05. The results showed there significant different between before and after drug counseling by discussion goup and lecture method used leaflet media, able to self-medication attitude improved such as knowledge and attitude about self-medication (P= 0.000), also it can to know both of methods as effective as to self-medication attitude which showed P=0.05. It\u27s mean both of drug counseling methods used as effective as to self-medication attitude improvement. Key words: self medication attitude, counseling methods, housewife, Banyumas

Alteration of water-soluble S-100 protein content in microembolized rat brain.

The amount of S-100 protein in rat brain embolized with carbon microspheres decreased in parallel with the development of cerebral edema as judged by water content, recovering to the normal range by 24h after embolization. These results suggest the participation of S-100 protein in the permeability characterisitics of nervous system capillaries known as the blood-brain barrier.</p

An Interview Professor Furuta

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