Dispersion-managed, high-power, Er-doped ultrashort-pulse fiber laser using carbon-nanotube polyimide film.

We investigated a dispersion-managed, passively mode-locked, ultrashort-pulse, Er-doped fiber laser using a polyimide film containing dispersed single-wall carbon nanotubes (SWNTs) and examined the dependence on net cavity dispersion and output coupling ratio using normal-dispersion fibers and a variable output coupler. For the dissipative soliton mode-locking condition, we achieved a pulse energy of 3.5 nJ and an average power of 114 mW, the highest values yet reported for an SWNT fiber laser under single-pulse operation.

Ultralow-repetition-rate, high-energy, polarization-maintaining, Er-doped, ultrashort-pulse fiber laser using single-wall-carbon-nanotube saturable absorber.

An ultralow-repetition-rate, all-polarization-maintaining (PM), Er-doped, ultrashort-pulse fiber laser was demonstrated using a single-wall-carbon-nanotube polyimide film. Using a ring cavity configuration, output pulses with pulse energy of 0.7-2.6 nJ were obtained at an ultralow repetition rate of 943-154 kHz for a fiber length of 0.1-1.3 km. A novel θ (theta) cavity configuration was proposed, which enabled us to reduce the required fiber length by half. A repetition rate of 132 kHz was achieved using this configuration with 909 m of PM fiber.

Polarization-maintaining, high-energy, wavelength-tunable, Er-doped ultrashort pulse fiber laser using carbon-nanotube polyimide film.

A high-energy, wavelength-tunable, all-polarization-maintaining Er-doped ultrashort fiber laser was demonstrated using a polyimide film dispersed with single-wall carbon nanotubes. A variable output coupler and wavelength filter were used in the cavity configuration, and high-power operation was demonstrated. The maximum average power was 12.6 mW and pulse energy was 585 pJ for stable single-pulse operation with an output coupling ratio as high as 98.3%. Wide wavelength-tunable operation at 1532-1562 nm was also demonstrated by controlling the wavelength filter. The RF amplitude noise characteristics were examined in terms of their dependence on output coupling ratio and oscillation wavelength.

All-polarization-maintaining Er-doped ultrashort-pulse fiber laser using carbon nanotube saturable absorber.

We present an all-polarization-maintaining Er-doped ultrashort-pulse fiber laser using a single-wall carbon nanotube polyimide nanocomposite saturable absorber. The maximum average power for single-pulse operation is 4.8 mW, and the repetition frequency is 41.3 MHz. Self-start and stable mode-locking operation is achieved. The RF amplitude noise is also examined and it is confirmed that the noise figure is as low as that of a solid-state laser. Using a polarization-maintaining anomalous dispersive fiber, a 314 fs output pulse is compressed to 107 fs via higher-order soliton compression. The peak power of the compressed pulse is up to 1.1 kW.

Ultrashort pulse-generation by saturable absorber mirrors based on polymer-embedded carbon nanotubes.

We demonstrate passive mode locking of solid-state lasers by saturable absorbers based on carbon nanotubes (CNT). These novel absorbers are fabricated by spin-coating a polymer doped with CNTs onto commercial dielectric laser-mirrors. We obtain broadband artificial saturable absorber mirrors with ultrafast recovery times without the use of epitaxial growth techniques and the well-established spin-coating process allows the fabrication of devices based on a large variety of substrate materials. First results on passive mode locking of Nd:glass and Er/Yb:glass lasers are discussed. In the case of Er/Yb:glass we report the to our knowledge shortest pulse generated in a self-starting configuration based on Er/Yb:bulk-glass: 68 fs (45 fs Fourier-limit) at 1570 nm wavelength at a pulse-repetition rate of 85 MHz.

A pedigree of amyotrophic chorea with acanthocytosis.

Several pedigrees of which some members showed a clinical syndrome consisting of mental changes, choreatic involuntary movements, limb muscles atrophy, and acanthocytosis have been reported in the United States and the United Kingdom. Such a case and some of the family members who had such abnormalities as acanthocytosis, hypo-beta-lipoproteinemia, convulsions, and confusion was observed. Results of biochemical analysis of catecholamines and their metabolites in CSF and urine showed an elevated value of norepinephrine in CSF and increased urinary secretion of DOPAC. The authors propose to designate this syndrome an amyotrophic chorea with acanthocytosis.

Studies on biological actions of dimethyl sulfoxide in familial amyloidosis.

DMSO was therapeutically administered to patients with FAP and in about half of the patients there was some clinical improvement. Urinary proteins were analyzed biochemically and immunochemically before and after DMSO administration in seven cases of amyloidosis. As the results, increased excretion of various proteins of different molecular weights in the urine was observed depending on cases and examined organs. The in vitro effects of DMSO on amyloid proteins were examined. DMSO-degraded amyloid proteins showed void-volume materials and lower molecular weight components on Sephadex G column elution profiles as did guanidine-degraded amyloid protein. Among various denaturating or reducing agents, DMSO is the least potent in dissolving amyloid fibrils into prealbumin-related proteins.

Immunohistochemical localization of neurotensin and beta-endorphin in the rat anterior pituitary gland.

Nakane's enzyme-labeled antibody technique revealed that cells containing neurotensin-like immunoreactivity were widely distributed in the anterior lobe of the pituitary body. Immunohistochemical studies on serial sections showed that a part of neurotensin positive anterior lobe cells contained beta-endorphin-like peptide simultaneously. The results show that beta-endorphin and neurotensin occur together in certain pituitary cells and this is an evidence of coexistence of more than one peptide within one anterior pituitary cell.

Discrete regional distributions of thyrotropin releasing hormone (TRH) receptor binding in monkey central nervous system.

Thyrotropin releasing hormone (TRH) directly influences central nervous system (CNS) function, independent of its pituitary action. Although these CNS effects have been behaviorally characterized, information is not yet available on the precise regional distribution of its receptor. TRH receptor binding was examined in the monkey CNS by the radioreceptor assay for clarifying the site of TRH action. TRH was bound to brain tissue membranes via high-affinity (Kd = 5.9 x 10(-9) M) and low-affinity (Kd = 11.2 x 10(-8) M) components. TRH receptor binding varied dramatically throughout the monkey brain, with more than 40-fold variation. The limbic system contained the greatest amount of binding. The next highest areas were the cerebral cortex, hypothalamus, interpeduncular nucleus and periaqueductal gray matter of the midbrain. Receptor binding was very low or not detectable in the medial thalamus, cerebellum, brain stem, spinal cord and white matter. These data suggest that TRH has an effect on the CNS via limbic system, cerebral cortex and midbrain.

The binding of [3H]nitrendipine to receptors for calcium channel antagonists in the heart, cerebral cortex, and ileum of rats.

The binding properties of the calcium channel antagonist, [3H]nitrendipine, were investigated in homogenates of the rat cerebral cortex, heart and ileum. The specific component of [3H]nitrendipine binding was consistent with mass-action behavior and was characterized by a high affinity dissociation constant in the range of 0.1-0.3 nM. A variety of other calcium channel antagonists inhibited the binding of [3H]nitrendipine with Ki's that agree generally with the ability of these drugs to block contractions of cardiac and smooth muscle. The inhibition of [3H]nitrendipine binding by other dihydropyridines was consistent with competitive antagonism whereas the inhibition caused by verapamil and D600 resembled negative heterotropic cooperativity. Consistent with this latter postulate was the observation that the kinetics of [3H]nitrendipine binding are altered by verapamil, with both the association rate and the dissociation rate being increased. La+3 and several divalent cations caused an inhibition of [3H]nitrendipine with the rank order of potency being Cd+2 greater than La+3 greater than Ni+2 greater than Co+2 = Mn+2 greater than Mg+2 = Ba+2 greater than Ca+2.

Identifications of 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 23 beta-tetrol, 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 24 alpha-tetrol, and 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 24 beta-tetrol in cerebrotendinous xanthomatosis.

The bile alcohols present in the feces of a patient with cerebrotendinous xanthomatosis were studied. Three bile alcohols which are different from any known natural bile alcohol were isolated as minor components of the fecal bile alcohol fraction. The structures of these compounds were established as 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 23 beta-tetrol, 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 24 alpha-tetrol, and 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 24 beta-tetrol by comparison with synthetic samples.

Ontogenetic development of the specific [3H]nitrendipine binding sites in the rat whole brain.

[3H]Nitrendipine binding sites are localized much more in the synaptosomal membrane than in the mitochondrial and microsomal membranes. To use a whole homogenate (crude membrane fraction) for the purpose of observing nitrendipine binding sites in the synaptosomal membrane instead of P2-B fraction has its reason. The Bmax of specific nitrendipine binding in the rat brain increases linearly until it reaches to the adult level after birth. High affinity binding at early developmental stages shifts to low affinity after the 7 day postnatal stage. Autoradiographically, nitrendipine binding sites are rich in the interpeduncular nucleus, olfactory bulb, hippocampus and superior colliculus in an adult rat. In autoradiography, the density in the hippocampus increases gradually until it reaches the adult level at the 28 day postnatal stage.