Photo-, thermo-, solvato-, and electrochromic spiroheterocyclic compounds.

Background Breathing is controlled by a negative-feedback system in which an increase in the partial pressure of arterial carbon dioxide stimulates breathing and a decrease inhibits it. Although enhanced sensitivity to carbon dioxide helps maintain the partial pressure of arterial carbon dioxide within a narrow range during waking hours, in some persons a large hyperventilatory response during sleep may lower the value below the apneic threshold, thereby resulting in central apnea. I tested the hypothesis that enhanced sensitivity to carbon dioxide contributes to the development of central sleep apnea in some patients with heart failure. Methods This prospective study included 20 men who had treated, stable heart failure with left ventricular systolic dysfunction. Ten had central sleep apnea, and 10 did not. The patients underwent polysomnography and studies of their ventilatory response to carbon dioxide. Results Patients who met the criteria for central sleep apnea had significantly more episodes of cen...

https://www.nejm.org/doi/pdf/10.1056/NEJM199909233411304

A Mechanism of Central Sleep Apnea in Patients with Heart Failure

The crystallization behavior of Ge2Sb2Te5 thin films has been analyzed by atomic force microscopy and optical reflection measurements on various time scales in order to determine the crystallization kinetics including the crystallization mechanism, the corresponding activation barrier, and the Avrami coefficient. On the minute time scale, thin amorphous films were isothermally crystallized in a furnace under a protective Ar atmosphere. From these measurements the activation energy for crystallization was determined to be (2.0±0.2) eV, in close agreement with previous studies using different techniques. The isothermal measurements also revealed a temperature dependent incubation time for the formation of critical nuclei, which is compared with recent theories. On the nanosecond time scale, Ge2Sb2Te5 was locally crystallized with a focused laser. Either crystalline spots of submicron size were generated in an as deposited amorphous film or amorphous bits in an otherwise crystalline film were recrystallized. For the formation of crystalline spots in an as deposited amorphous film a minimum time of (100±10) ns was found, which is identified as the minimum incubation time for the formation of critical nuclei. In contrast, the complete crystallization of melt-quenched amorphous bits in a crystalline matrix was possible in 10 ns. This is attributed to the presence of quenched-in nuclei inside the amorphous bits. The combination of optical measurements with atomic force microscopy reveals the formation and growth of crystalline bits and shows that the crystal growth in vertical direction strongly affects the reflectivity changes.

Laser induced crystallization of amorphous Ge2Sb2Te5 films

The present paper reviews the results of experimental investigations of the photodoping of amorphous chalcogenides by metals, and in particular by silver. The kinetics of the photodissolution of the metal are described as also is the influence on the photodissolution rate of such factors as the wavelength and intensity of light, the composition and temperature of the semiconductor, and an external electric field. A separate section describes lateral diffusion. The properties of photodoped semiconductors (electrical, optical, photoelectric, etc.) are presented. The results in the literature are analysed, giving answers to such fundamental questions as the following. Where is the actinic light which is efficient for the photodissolution absorbed? Which is the diffusion-limiting step? What is the state of the diffusing species (neutral atoms or ions)? The dissolution of silver induced by electron or ion beams and the photodissolution of group II metals are mentioned. The experimental results are fol...

Photodoping of amorphous chalcogenides by metals

Colouration of tungsten oxide films: A model for optically active coatings

Sb‐Te alloy films are developed as rewritable optical recording materials based on amorphous crystalline phase transformations. The crystallization process of Sb‐Te sputtered films is systematically studied through measurement of recording characteristics to solve the trade‐off problem between data (amorphous) stability and erasing sensitivity. Sb2Te3 is shown to be the best practical phase change medium, having room‐temperature stability in amorphous states, short erasing times, and potentially good reversibility. The carrier‐to‐noise ratio of 50 dB in writing and a decrease in the carrier level of over 30 dB in erasing are achieved in dynamic measurement with a single beam optical head. These favorable properties are attributable to the wide composition margin for a single phase formation in the Sb‐Te alloy system.

Crystallization process of Sb‐Te alloy films for optical storage

The present invention provides a method for manufacturing freeze-dried blood cells, stem cells and platelets comprising the steps of: pre-treating a liquid selected from the group consisting of blood including blood cells, bone marrow fluid (hemopoietic stem cells), and platelets in blood plasma, with a solution containing at least one substance selected from the group consisting of saccharide, biopolymer, acid and acid salt; conducting granulation of the aforementioned pre-treated liquid into a granules of a predetermined size; performing rapid cooling of the granules; and drying the resultant frozen material by sublimation of the water content contained therein.

Freeze-dried blood cells, stem cells and platelets and manufacturing method for the same

The crystallization process and amorphous stability of vacuum deposited TeSeCu alloy film was studied. Dependence of crystallization temperature ( T c ) and activation energy ( E a ) on the alloy film composition was investigated by differential scanning calorimeter. The Cu concentration influences the number of crystallization stages in this ternary alloy film. Two crystallization stages with different crystallization temperatures exist, when Cu is more than 8 at% and less than 30 at%. But only one crystallization stage occurs at higher than 30 at% Cu. The most stable amorphous state is obtained at 30 at% Cu and at either Se/(Se + Te) is 8 or 15 at% Se. Addition of Se has an effect of stabilizing the amorphous state of this alloy, but the Se concentration does not influence the number of crystallization stage. When in (Te 100− x Se x 0.7 Cu 30 alloy film, the x is between 15 and 50, the very high value of activation energy (about 3.8 eV) is obtained.

Crystallization of vacuum deposited TeSeCu alloy film

The crystallization process of sputtered InTe alloy films was studied in detail using a differential scanning calorimeter (DSC) in order to determine if the alloy can be used as a phase-change type optical recording material. The crystallization process is well described by the Johnson-Mehl-Avrami (JMA) equation. In a 50–60 at.% TeIn alloy system, good material characteristics were obtained, that is, a high crystallization temperature above 250°C, a high activation energy of more than 3.0 eV and a frequency factor of more than 10 30 s −1 . The exponent n varied from 1.5 to 3 in these compositions. An incubation time was also observed in the present experiments. In addition to studying these material characteristics, the crystallization speed was estimated with a static write-erase tester using semiconductor laser irradiation. It was found that the incubation time greatly influences high speed crystallization.

Crystallization process of InTe alloy films for optical recording

The present invention relates to a UV-A,UV-B discriminating sensor provided with a photochromic compound or photochromic composition as the sensor portion, the photochromic compound or photochromic composition coloring under exposure to UV of wavelength greater than or equal to 280nm or less than or equal to 400nm, and wherein at least a portion of the photochromic layer is covered with a layer containing a pigment which absorbs UV of wavelength less than 320nm, or with a layer containing a pigment which absorbs UV of a wave length greater than or equal to 320nm but less than or equal to or equal to 400nm.

Nobuhiro Funakoshi

Papers

Crystallization process of Sb‐Te alloy films for optical storage

Freeze-dried blood cells, stem cells and platelets and manufacturing method for the same

Crystallization of vacuum deposited TeSeCu alloy film

Crystallization process of InTe alloy films for optical recording

UV-A, UV-B discrimination sensor