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Laser-driven neutron source (LDNS) is attracting interest for several reasons including (i) compactness of the source, (ii) neutron pulse shortness and (iii) transportability of laser beam. Through reviewing recent activities, we discuss the characteristics of LDNS in a comparison with accelerator-based neutron facilities (ABNF). Especially, we discuss the potential and limit of LDNS by showing that neutrons ranging from meV to MeV in energy were generated by LDNS and applied to neutron analysis and fundamental science. [ABSTRACT FROM AUTHOR]

The (a,b) plane angular dependence of the third-order nonlinear optical susceptibility, χ ( 3 ) , of a c-cut paratellurite (α-TeO2) single crystal was quantitatively evaluated here by the Z-scan technique, using a Ti:sapphire femtosecond laser operated at 800 nm. In particular, the mean value Re( ⟨ χ ( 3 ) ⟩ a , b )(α-TeO2) of the optical tensor has been extracted from such experiments via a direct comparison with the data collected for a fused silica reference glass plate. A R e ( ⟨ χ ( 3 ) ⟩ ( a , b ) ( α − TeO 2 ) ) : R e ( χ ( 3 ) ) ( SiO 2 glass ) ratio roughly equal to 49.1 is found, and our result compares thus very favourably with the unique experimental value (a ratio of ∼50) reported by Kim et al. [J. Am. Ceram. Soc. 76, 2486 (1993)] for a pure TeO2 glass. In addition, it is shown that the angular dependence of the phase modulation within the (a,b) plane can be fully understood in the light of the strong dextro-rotatory power known for TeO2 materials. Taking into account the optical activity, some analytical model serving to estimate the diagonal and non-diagonal components of the third order nonlinear susceptibility tensor has been thus developed. Finally, Re( χ xxxx ( 3 ) ) and Re( χ xxyy ( 3 ) ) values of 95.1 × 10 − 22 m 2 / V 2 and 42.0 × 10 − 22 m 2 / V 2 , respectively, are then deduced for a paratellurite single crystal, considering fused silica as a reference. [ABSTRACT FROM AUTHOR]

This article discusses a new imaging technique called Detective Flow Imaging using endoscopic ultrasound (DFI-EUS) for diagnosing pancreatic ductal adenocarcinoma (PDAC). The study analyzed data from patients who underwent DFI-EUS for evaluating pancreatic solid tumors. The researchers created a diagnostic algorithm based on the DFI-EUS findings and evaluated its accuracy in diagnosing PDAC. The results showed that DFI-EUS is a promising method for diagnosing PDAC, but further validation is needed in future studies. [Extracted from the article]

Purpose: This study evaluated the bone-regeneration properties of titanium fiber web (TW) that had been coated with a thin hydroxyapatite (HA) layer using the molecular precursor method. Materials and Methods: TW disks with or without the thin HA coating were implanted into rat cranial bone defects. The rats were sacrificed after 3 or 6 weeks. New bone formation into the TW was evaluated. Results: The porous structure of TW was clearly maintained after the HA coating was applied. In the HA-coated TW group, new woven bone was observed in the majority of the disks after 6 weeks, whereas the control (uncoated TW) group showed limited new bone formation in the interior. The bone formation ratio in the HA-coated group was significantly higher than in the control group (20.6% and 59.1% after 3 and 6 weeks, respectively, versus 2.0% and 15.5%, respectively; P < .05). Conclusions: The molecular precursor method of applying a thin HA coating to TW appeared to effectively enhance new bone formation through maintenance of TW porosity and promotion of osteoconductivity in the TW three-dimensional scaffold. Int J Oral Maxillofac Implants 2010;25:888-892. [ABSTRACT FROM AUTHOR]

Secondary ion mass spectra have been measured for the first time for a liquid ethanol target bombarded by 2.0 MeV He+ ions. Positive and negative ion spectra exhibit evidently a series of cluster ions of the forms [(EtOH)nH]+ and [(EtOH)n-H]-, respectively, in addition to light fragment ions from intact parent molecules. It was found that these cluster ions are produced only from liquid phase ethanol. Both positive and negative secondary ion spectra show similar cluster size distributions with almost the same decay slope. We also present for the first time the cluster ion distribution emitted from the liquid at different liquid temperatures. [ABSTRACT FROM AUTHOR]

PURPOSE: The influence of thin carbonate-containing apatite (CA) coating on the trabecular bone response to titanium implants was investigated. MATERIALS AND METHODS: Thin CA coatings were deposited by a new method known as the molecular precursor method. Using a precursor solution composed of an EDTA-calcium complex, a CA film was deposited on the titanium surfaces. Uncoated and CA-coated titanium were placed in the trabecular bone of the left and right femoral condyles of 16 rabbits. After implantation periods of 2, 4, 8, and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. RESULTS: Histologic evaluation revealed new bone formation around the uncoated and CA-coated implant surfaces after only 4 weeks of implantation. After 12 weeks, mature trabecular bone surrounded all implants. At 4 and 8 weeks of implantation, no difference existed in bone contact between uncoated and CA-coated implants. After 12 weeks of implantation, the CA-coated implant group showed a significantly higher percentage of bone contact than the uncoated implant group. DISCUSSION AND CONCLUSION: The present study demonstrated that thin CA coatings applied using the molecular precursor method showed greater bone-to-implant contact during the healing phase than uncoated controls. The results were similar to those observed with implants with calcium phosphate coatings deposited with a physical vapor deposition technique. [ABSTRACT FROM AUTHOR]

Presents a study that investigated theoretically and experimentally the gain characteristics in quantum-well lasers. Use of Hakki and Paoli's method in measuring the polarization gain-current characteristics of (111)- and (100)-oriented gallium arsenide/aluminum gallium arsenic single-quantum-well lasers; Details on the experimental results of polarization-dependent spontaneous emission; Conclusion of the study.

Focuses on a study that investigated the energy-band structure of aluminum arsenide and gallium arsenide short-period superlattices by using photoluminescence excitation spectroscopy. Sample preparation; Results and discussion; Conclusion.

The control problem of a linear discrete-time dynamical system over a multi-hop network is explored. The network is assumed to be subject to packet drops by malicious and nonmalicious nodes as well as random and malicious data corruption issues. We utilize asymptotic tail-probability bounds of transmission failure ratios to characterize the links and paths of a network as well as the network itself. This probabilistic characterization allows us to take into account multiple failures that depend on each other, and coordinated malicious attacks on the network. We obtain a sufficient condition for the stability of the networked control system by utilizing our probabilistic approach. We then demonstrate the efficacy of our results in different scenarios concerning transmission failures on a multi-hop network. [ABSTRACT FROM AUTHOR]

SUMMARY: Currently, the remote control such as the bilateral control which enables transmitting the multimodal information has been studied. However, remote control has not been reached while perceiving the wind, gravity, and the condition of the ground on the moving object at the remote place. When it is possible to perceive the external force applied to the moving object, it is possible to perform an appropriate operation sensuously according to a remote place such as a slope or a gravel road. Therefore, we propose a high immersive telexistence system with head mounted display and the six‐axis motion base which enables transmitting the inertia and force information of the moving vehicle, and 360‐degree image of moving object's surroundings at real‐time. [ABSTRACT FROM AUTHOR]

A Neutron/Gamma-ray combined inspection system for hidden special nuclear materials (SNMs) in cargo containers has been developed under a program of Japan Science and Technology Agency in Japan. This inspection system consists of an active neutron-detection system for fast screening and a laser Compton backscattering gamma-ray source in coupling with nuclear resonance fluorescence (NRF) method for precise inspection. The inertial electrostatic confinement fusion device has been adopted as a neutron source and two neutron-detection methods, delayed neutron noise analysis method and high-energy neutron-detection method, have been developed to realize the fast screening system. The prototype system has been constructed and tested in the Reactor Research Institute, Kyoto University. For the generation of the laser Compton backscattering gamma-ray beam, a race track microtron accelerator has been used to reduce the size of the system. For the NRF measurement, an array of LaBr3(Ce) scintillation detectors has been adopted to realize a low-cost detection system. The prototype of the gamma-ray system has been demonstrated in the Kansai Photon Science Institute, National Institutes for Quantum and Radiological Science and Technology. By using numerical simulations based on the data taken from these prototype systems and the inspection-flow, the system designed by this program can detect 1 kg of highly enriched 235U (HEU) hidden in an empty 20-ft container within several minutes. [ABSTRACT FROM PUBLISHER]

Focuses on the preparation of indium-gallium (Ga)-arsenic (As) single strained quantum well lasers with gallium arsenide/aluminum-Ga-As short-period superlattice barrier layers. Use of molecular beam epitaxy; Cause of the reduction of carrier leakage from quantum well to barrier layers; Effect of heterobarrier height on internal quantum efficiency at elevated temperatures.

Examines high-power cw operation in a (111)-oriented gallium arsenide/AlGaAs single-quantum-well lasers prepared by molecular beam epitaxy (MBE). Elimination of the slip line defects in the MBE-grown wafers; Layer sequence of laser diodes; Output-current characteristics of the devices with the aluminum arsenide mole fraction.

Presents a study which investigated high-purity aluminum gallium arsenide grown by molecular beam epitaxy using a superlattice buffer layer. Method of the study; Results and discussion; Conclusion.

Background/Objectives:There have been few studies on the association of fruit and vegetable (FV) intake with cardiovascular disease (CVD) risk in Asian populations where both dietary habits and disease structure are different from western countries. No study in Asia has found its significant association with stroke. We examined associations of FV intake with mortality risk from total CVD, stroke and coronary heart diseases (CHDs) in a representative Japanese sample.Methods:A total of 9112 participants aged from 24-year follow-up data in the NIPPON DATA80, of which baseline data were obtained in the National Nutrition Survey Japan in 1980, were studied. Dietary data were obtained from 3-day weighing dietary records. Participants were divided into sex-specific quartiles of energy adjusted intake of FV. Multivariate-adjusted hazard ratios (HRs) were calculated between strata of the total of FV intake, fruit intake and vegetable intake. The adjustment included age, sex, smoking, drinking habit and energy adjusted intakes of sodium and some other food groups.Results:Participants with higher FV intake were older, ate more fish, milk and dairy products and soybeans and legumes and ate less meat. Multivariate-adjusted HR (95% confidence interval; P; P for trend) for the highest versus the lowest quartile of the total of FV intake was 0.74 (0.61-0.91; 0.004; 0.003) for total CVD, 0.80 (0.59-1.09; 0.105; 0.036) for stroke and 0.57 (0.37-0.87; 0.010; 0.109) for CHD.Conclusions:The results showed that higher total intake of FVs was significantly associated with reduced risk of CVD mortality in Japan. [ABSTRACT FROM AUTHOR]