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N-acetylaspartate (NAA) levels and serum brain-derived neurotrophic factor (BDNF) levels in patients with first-episode schizophrenia psychosis and age- and sex-matched healthy control subjects were investigated. In addition, plasma levels of homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were compared between the two groups.
Method:
Eighteen patients (nine males, nine females; age range: 13–52 years) were enrolled in the study, and 18 volunteers (nine males, nine females; age range: 15–49 years) with no current or past psychiatric history were also studied by magnetic resonance spectroscopy (MRS) as sex- and age-matched controls.
Results:
Levels of NAA/Cr in the left basal ganglia (p = 0.0065) and parieto-occipital lobe (p = 0.00498), but not in the frontal lobe, were significantly lower in patients with first-episode schizophrenia psychosis than in control subjects. No difference was observed between the serum BDNF levels of patients with first-episode schizophrenia psychosis and control subjects. In regard to the plasma levels of catecholamine metabolites, plasma MHPG, but not HVA, was significantly lower in the patients with first-episode psychosis than in control subjects. In addition, a significantly positive correlation was observed between the levels of NAA/Cr of the left basal ganglia and plasma MHPG in all subjects.
Conclusions:
These results suggest that brain NAA levels in the left basal ganglia and plasma MHPG levels were significantly reduced at the first episode of schizophrenia psychosis, indicating that neurodegeneration via noradrenergic neurons might be associated with the initial progression of the disease.
The ALMA twenty-six arcmin2 survey of GOODS-S at one millimeter (ASAGAO) is a deep (1σ ∼ 61μJy/beam) and wide area (26 arcmin2) survey on a contiguous field at 1.2 mm. By combining with archival data, we obtained a deeper map in the same region (1σ ∼ 30μJy/beam−1, synthesized beam size 0.59″ × 0.53″), providing the largest sample of sources (25 sources at 5σ, 45 sources at 4.5σ) among ALMA blank-field surveys. The median redshift of the 4.5σ sources is 2.4. The number counts shows that 52% of the extragalactic background light at 1.2 mm is resolved into discrete sources. We create IR luminosity functions (LFs) at z = 1–3, and constrain the faintest luminosity of the LF at 2 < z < 3. The LFs are consistent with previous results based on other ALMA and SCUBA-2 observations, which suggests a positive luminosity evolution and negative density evolution.
The drill hole at “Byrd” station, which was completed in January 1968 to a vertical gerpth of 7 063 ft (2 153 m) below the top of the hole casing, was resurveyed in January 1975 to a vertical gerpth of 4 835 ft (1 474 m)· Inclination and azimuth measurements were mager with a Parsons multiple shoe inclinometer and compared with the earlier measurements mager during drilling. The results indicate a progressively increasing displacement with gerpth to a value of 51.2 ft (15.6 m) or about 7.3 ft/year (2.23 m/year) at the 4 835 ft (1 474 m) level. The direction of movement relative to the surface varies freom south-west at 300 ft (91.5 m) to north-east at 1 100 ft (335 m) to east at 3 368 ft (1 027 m) to north-east at 4835 ft (l 474 m), indicative of a complex twisting motion. An increase in accessible gerpth along the hole axis of 18 ft (549 m) beyond the 1969 gerpth was noted. No attempt was mager to measure hole diameter or vertical strain. It is recommengerd that the hole be resurveyed in 3-5 years if it is still logistically feasible, using a more up-dated inclinometer.
Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging has been used to detect alterations in the composition of inner-ear fluid. This study investigated the association between hearing level and the signal intensity of pre- and post-contrast three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging in patients with sudden-onset sensorineural hearing loss.
Method:
Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging was performed in 18 patients with sudden-onset sensorineural hearing loss: 12 patients with mild-to-moderate sensorineural hearing loss (baseline hearing levels of 60 dB or less) and 6 patients with severe-to-profound sensorineural hearing loss (baseline hearing levels of more than 60 dB).
Results:
High-intensity signals in the inner ear were observed in two of the six patients (33 per cent) with severe-to-profound sensorineural hearing loss, but not in those with mild-to-moderate sensorineural hearing loss (mid-p test, p = 0.049). These signals were observed on magnetic resonance imaging scans 6 or 18 days after sensorineural hearing loss onset.
Conclusion:
The results indicate that three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging is not a useful tool for detecting inner-ear abnormalities in patients with mild sensorineural hearing loss.
A large fraction of the AGN output power is emitted in the X-rays, in a region very close to the supermassive black hole (SMBH). The most distinctive feature of the X-ray spectra of AGN is the iron Kα line, often observed as the superposition of a broad and a narrow component. While the broad component is found in only ~ 35–45% of bright nearby AGN, the narrow component has been found to be ubiquitous. The narrow Fe Kα line is thought to be produced in the circumnuclear material, likely in the molecular torus. Given its origin, this feature is possibly the most important tracer of neutral matter surrounding the SMBH. One of the most interesting characteristics of the narrow Fe Kα line is the decrease of its equivalent width with the continuum luminosity, the so-called X-ray Baldwin effect (Iwasawa & Taniguchi 1993). This trend has been found by many studies of large samples of type-I AGN, and very recently also in type-II AGN (Ricci et al. 2013c, submitted to ApJ). The slope of the X-ray Baldwin effect in type-II AGN is the same of their unobscured counterparts, which implies that the mechanism at work is the same. Several hypothesis have been put forward in the last decade to explain the X-ray Baldwin effect: i) a luminosity-dependent variation in the ionisation state of the iron-emitting material (Nandra et al. 1997); ii) the decrease of the number of continuum photons in the iron line region with the Eddington ratio, as an effect of the well known correlation between the photon index and the Eddington ratio (Ricci et al. 2013b, submitted to MNRAS); iii) the decrease of the covering factor of the torus with the luminosity (e.g., Page et al. 2004, Ricci et al. 2013a A&A 553, 29) as expected by luminosity-dependent unification models (e.g., Ueda et al. 2003). In my talk I will review the main characteristics of the narrow Fe K? line, and present the results of our recent works aimed at explaining the X-ray Baldwin effect using iron-line emitting physical torus models (Ricci et al. 2013a, b), and at understanding the origin of the Fe K? line (Ricci et al. 2013c). I will focus in particular on the importance of the Fe Kα line as a probe of the evolution of the physical characteristics of the molecular torus with the luminosity.
We show that the dispersion in the Schmidt-Kennicutt (SK) law in galaxies is affected significantly by the evolutionary stage of star forming molecular gas, using narrow band Paα imaging of Taffy I, an interacting pair of galaxies. Star forming regions in the system show very uniform ages except for the bridge region, and the SK law of regions at the same age show a exceptionally tight SK law.
In order to enhance the safety of geological disposal and the reliability of the safety assessment carried out for each stage of the geological disposal project, an assessment methodology focused on a sensitivity analysis and an evaluation of importance, which incorporates “system understanding” and “information feedback” into the existing assessment approach, has been developed in this study. In this paper, the assessment methodology and the assessment results as applied for the transuranic (TRU) waste disposal system in Japan will be described. In the sensitivity analysis, an approximate analytical solution was used in order to understand the response characteristics of the engineered barrier system (EBS). In the importance evaluation, important factors relating to the robustness of system safety were identified based on the response characteristics. Furthermore, important features, events, and processes (FEPs) related to such factors and high-impact scenarios were identified based on the information accumulated through “system understanding” and “information feedback”. Based on this approach, the robustness of the TRU waste disposal system was assessed and measures for improving the robustness were identified.
Information about positions and velocities of stars that will be gained in the era of GAIA is crucial for determining dynamical structure in our Galaxy. The distribution function of all component objects in our Galaxy is fundamental for describing its dynamics. However, only the distribution function of observable stars is obtained from space astrometry observations, and it is therefore necessary to develop theoretical studies of how to construct the distribution function of all matter including dark matter and unobservable stars using astrometric data of observable stars. This procedure falls into three categories.
Protective immunity of homologous challenge infection was examined in jirds after drug-abbreviated infection with Brugia pahangi. Mebendazole (MBZ) treatment at the early prepatent (5–7 weeks of post infection) or the late prepatent (7–9 weeks of post infection) period was highly effective in causing almost complete eradication of the primary infection. After challenge infection, the worm burden was significantly reduced 19% (31·1 in average) and 77% (9·5) to that of the controls (38·8 and 41·7), respectively. The magnitude of eosinophil response paralleled the degree of protection. No or only a few microfilariae were seen after challenge infection in jirds treated during the prepatent periods. They were also resistant to intravenous challenge with the microfilariae of B. pahangi. MBZ treatment at the patent period was, on the contrary, incomplete against primarily infected adult worms, and was not able to induce either significant protection (30·1 vs 33·1 in control) or eosinophil response to the challenge infection.
Epithelioid sarcoma is an aggressive, malignant tumour of the soft tissue which tends to arise in proximity to large tendons and aponeuroses. We report the case of a patient presenting with an epithelioid sarcoma arising in the neck. A 56-year-old man was referred with a three-year history of a sensory disorder as well as a slowly growing mass in his right neck. The patient underwent resection of the tumour by means of a conservative neck dissection. The final diagnosis, based on the histological and immunohistochemical findings, was epithelioid sarcoma. Radiotherapy was performed after the operation. The post-operative course was uneventful, and there was no local recurrence or distant metastasis.
An anterior glottic web in adults comprises a bridge of scar tissue commonly formed as a result of iatrogenic laryngeal injury. Traditionally, procedures such as transcervical midline thyrotomy and keel placement have been used to repair this condition. However, we recently repaired an anterior glottic web using a new surgical procedure involving a silicone tube instead of a keel. We herein report this case, in which we placed a silicone tube at the anterior commissure after resection of an anterior glottic web, under endolaryngeal microsurgery, without performing a tracheostomy.
Measurements on nonlinear processes caused by multiphoton absorption and electron avalanche in optical thin films have been carried out using KrF lasers of 20-ns and 1.7-ps pulse duration. Multiphoton absorption of the order of 10-7 J was detected by a photoacoustic signal, and the nonlinear growth of photo-induced current due to the electron avalanche was analyzed dynamically. The correlation between damage threshold and carrier lifetime was investigated for oxide and fluoride coatings.
Bandwidth effects on laser-plasma interaction were investigated with a ¼-μm laser. Planar targets were irradiated with a 1- to 40-cm–1 bandwidth laser at I = 1 × 1013–4 × 1015 W/cm2. Above 3 × 1013 W/cm2, stimulated Brillouin scattering (SBS) was observed with 1 cm–1 light. This process was strongly reduced with a 40-cm–1 light. Evolution of the convective SBS was studied with 1-D fluid simulation code. Bandwidth effect on the SBS growth was discussed to compare the theoretical prediction and experimental results. The scalelength dependence exists for the SBS reduction with a broadband laser.
An atomic model of the laser-produced Al plasma has been developed and used to analyze excitation processes of recombination pumping soft X-ray lasers. A soft X-ray gain for H-like Balmer-α line and He-like 3d-2p transition in short-pulse intense KrF laser (IL = 1014–1015 W/cm2, T = 10–100 ps)-produced Al plasmas are calculated for various laser temporal pulse shapes to find the condition for efficient production of population inversion. Results from different models are compared and requirements for the atomic model for X-ray laser design are discussed.
In order to compare the bubble dynamics of various quantum liquids, we performed the visual observation of a sound-induced bubble in a normal liquid 4He, pure superfluid 4He, and superfluid 3He–4He liquid mixtures of saturated and unsaturated 3He concentrations. When an acoustic wave pulse was applied to these liquids under saturated vapour pressure, a macroscopic bubble was generated on the surface of a piezoelectric transducer. For all liquids, the size of the bubble increased, as a higher voltage was applied to the transducer at a fixed temperature. In the normal 4He we observed a primary bubble surrounded with many small bubbles which ascended upward together. In contrast to normal phase, only one bubble was generated in the superfluid 4He, and its shape proved to be highly irregular with an ill-defined surface. In the 3He saturated superfluid mixture, we also observed a solitary bubble but with a nearly perfect spherical shape. The bubble in this mixture expanded on the transducer surface, grew to a maximum size of the order of 1 mm and then started shrinking. As the bubble detached from the transducer with shrinking, we clearly detected an origination of the upward jet flow which penetrated the bubble. The jet velocity in the liquid mixture was approximately 102–103 times smaller than in water. At the final stage of the process we could sometimes observe a vortex ring generation. It is interesting that, though the bubble size and time scale of the phenomenon differ from those in water, the behaviour in the collapsing process had much in common with the simulation study of the vortex ring generation in water. In addition, for the mixture with the unsaturated 3He concentration of about 25% at 600 mK, the shape of the upward jet was observed distinctly, using more precise measurement with shadowgraph method.
Two aluminosilicate oxyfluoride glass systems, a lead-cadmium-aluminosilicate oxyfluoride and a lithium-lanthanum-aluminosilicate oxyfluoride, doped with different TbF3 concentrations, have been fabricated and investigated. By appropriate heat treatment of the as-prepared glasses above, transparent glass-ceramics (TGC) were obtained. The glass-ceramics contain Tb:Pb(Cd)F2 or Tb:LaF3 nano-crystals in the glass-matrix. Differential scanning calorimetry, Raman scattering, and luminescence under both UV and β-particle excitation have been investigated on as-prepared glasses and glass-ceramics. It has been found that the terbium-doped lithium-lanthanum-aluminosilicate oxyfluoride glass exhibits good UV excited luminescence and β-induced luminescence. The luminescence yield increases for glass-ceramic compared to that of the as-prepared glass. The including of LaF3 in the glass-matrix is beneficial for a higher Tb-doping concentration and a high light yield. The light yield of lithium-lanthanum-aluminosilicate oxyfluoride glass and glass-ceramic is comparable to that of Schott IQI-301 product. However, the terbium-doped lead-cadmium-aluminosilicate oxyfluoride glass and glass-ceramic have a detrimental luminescence performance. The lead cations in the glass-matrix may create non-bridging oxygen defects, which are a strong source of charge traps, and correlated to a strong Raman “Boson” peak.
Tb-doped Li2O-LaF3-Al2O3-SiO2 (LLAS) glasses containing silver were fabricated using melt-quenching technique. Silver nanoparticles (NPs) in glass matrix were confirmed by optical absorption and X-ray diffraction (XRD). The nucleation of silver NPs was controlled by heat-treatment. A broad absorption band peaked at about 420 nm was observed due to surface plasmon resonance (SPR) of the silver NPs. This SPR absorption of silver NPs increases with the time of heat-treatment. Photoluminescence (PL) emission and excitation spectra were measured on Tb-doped LLAS glasses with and without silver NPs. Strong Tb3+ luminescence was observed. For excitation at 325 nm, luminescence of Tb3+ ions increases for the glass containing silver NPs compared to that in the glass without silver NPs. After further heat-treatment at 520 °C for 5 hours, Tb3+ luminescence decreased. Our luminescence results suggest that there are two competitive effects, enhancement and quenching effects, acting on Tb3+ luminescence in the glass containing silver NPs. The enhancement of Tb3+ luminescence is attributed to local field effects due to the excitation of SPR of silver NPs. The quenching effect in the presence of Ag NPs suggests an energy transfer from Tb3+ ions to silver NPs exists, which may provide an additional non-radiative relaxation pathway for the excited Tb3+ ions.
Photoluminescence (PL) of Er-doped ZnO nanoparticle films was studied. The films were fabricated using e-beam evaporation. The films were subsequently annealed at 700 °C in air for an hour. The atomic force microscopy (AFM) image revealed nano-sized ZnO particles. PL was measured at two excitation wavelengths, 325 and 514.5 nm. The 325 nm is used for exciting the ZnO host semiconductor and 514.5 nm is used for directly exciting Er3+ ions in the ZnO films. Er3+ luminescence was observed from the annealed film using either indirect (325 nm) or direct (514.5 nm) excitations. It has been found that the indirect excitation is about 40 times more efficient than the direct excitation in producing 1.54 μm PL. With indirect excitation, the Er3+ luminescence observed is attributed to energy transfer from ZnO host to the Er3+ ions doped. Energy transfer from e-h pairs resulting from ZnO host excitation may provide efficient routes for exciting Er3+ ions inside nano-crystalline particles of the films.
We have designed a compact solid compressor by stimulated Brillouin scattering (SBS), which consists of two right angle prisms and a fused silica glass block. A 13–16 ns Nd:YAG laser pulse has been temporally compressed to 1 ns or less phase conjugation pulse in a fused-quartz and fused-silica glass at four different wavelengths. Maximum reflectivity of SBS was 90–95% without damage. The brightness of the compressed pulse was about ten-fold higher than that of the incident pulse. Damage-free operation using fused quartz glass as a better phase conjugation material could lead to the construction of a more compact, laser-diode-pumped, and all-solid-state laser system.