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1.
Solution- and solid-state c.d. spectra, as well as surface energetics values, were collected for a series of peptides derived from human salivary proline-rich glycoprotein (PRG). The acronyms and sequences for these peptides are as follows: PRG9-2 = NH2-G(1)-P(2)-CONH2, PRG9-3 = NH2-G(1)-P(2)-P(3)-CONH2, PRG9-4 = NH2-G(1)-P(2)-P(3)-P(4)-CONH2, PRG9-5 = NH2-G(1)-P(2)-P(3)-P(4)-H(5)-CONH2, PRG9-6 = NH2-G(1)-P(2)-P(3)-P(4)-H(5)-P(6)-CONH2, PRG9-7 = NH2-G(1)-P(2)-P(3)-P(4)-H(5)-P(6)-G(7)-CONH2, PRG9-8 = NH2-G(1)-P(2)-P(3)-P(4)-H(5)-P(6)-G(7)-K(8)-CONH2, and PRG9-9 = NH2-G(1)-P(2)-P(3)-P(4)-H(5)-P(6)-G(7)-K(8)-P(9)-CONH2. The presence of stable poly-L-proline II-like 'mini' helices in the solution state was found to be dependent on peptide chain length, pH, salt, and organic solvent type. Other conformational features such as kinks and beta-/gamma-turns were also found in the larger peptides. Solid-state peptide conformations were not necessarily related to their solution-state counterparts. Poly-L-proline II-like 'mini' helices, kinks, and beta-/gamma-turns were similarly found in the various substrate-bound PRG9 peptides. Surface energetics parameters suggested specific orientations for PRG9 peptides and their constituent acids and homopolymers.  相似文献   
2.
Since a decrease in muscle mass of elderly people, the physical burden of them in standing‐sitting motion of a seat are increasing than young people. For this problem, several standing‐sitting support systems have been developed, and evaluations of these systems focusing on a reduction of physical load have been discussed. However, these evaluations are of support systems with an active actuators or of support systems when they use a handrail and a standing aid. Thus, an evaluation of a support system with only passive actuators has not been reported. In this paper, in standing motion with using a standing‐sitting support system with passive rotational seat mechanism which our group proposes, we objectively evaluate an effectiveness of the passive rotational seat mechanism by statistical analysis.  相似文献   
3.
Allophane and imogolite are naturally occurring aluminum silicate soil constituents with nano-ball and nano-tube morphology. Wall of the both materials is composed of Al(OH)3 sheet with orthosilicic acid attached to it. Synthesis of allophane and imogolite can be controlled by addition of alkali and alkaline-earth metal ions. The main reaction product without or with small amounts addition of the metal ions is imogolite, while allophane forms when the metal ions were much added. The effect of metal ions on facilitating allophane formation and inhibition of imogolite formation were greater in the following order of Na, K < Ca, Mg. These metal ions affect the degree of dissociation of Si–OH group of orthosilicic acid, which may causes differential formation of allophane and imogolite. Structure optimization of the proto-imogolite model, precursor of allophane and imogolite, showed that when the Si–OH was undissociated, the shape of proto-imogolite model was transformed to asymmetrical in molecular configuration. This caused curling of the proto-imogolite model, which lead to formation of imogolite tube. On the other hand, when the Si–OH was dissociated, the shape of the proto-imogolite model was transformed to symmetrical configuration. This model curved to make a hollow sphere with placing the orthosilicic acid inside the sphere (allophane). Both of the experimental and molecular orbital calculation results proved that the dissociation of the Si–OH has an important role during the differential formation of allophane and imogolite.  相似文献   
4.
5.
The relation between optical-fiber dispersion and directly modulated distributed-feedback laser diode (DFB LD) spectral spread in multigigabit-per-second long-span transmission systems is discussed. It is observed that two peak spectra at the leading edge of the pulse induce spectral spread in directly modulated DFB LDs. Specifications for the difference between the DFB LD oscillation wavelength and the optical-fiber zero-dispersion wavelength in a multigigabit-per-second long-span transmission system, considering these two peak spectra, are predicted. Experimental confirmation was provided by 2-Gb/s-140-km and 5-Gb/s-100-km transmission experiments, using 1.5-μm zero-dispersion shifted optical fiber  相似文献   
6.
The optical cross-connect (OXC) system described in this paper increases the operation flexibility and reliability of the trunk-line optical networks used for data communication. It features an OXC node comprised of a photonic switching network and a conventional electric switching network that are connected hierarchically. The operation and management scheme proposed for this OXC system uses the concept of an optical path and an optical section. The OXC system allows hitless network reconfiguration by switching the photonic switches gradually and without interference effects. An experimental OXC network showed that a broken optical path is restored, by rerouting, within 50 ms. Experiments using a LiNbO3 8×8 photonic switch matrix also showed that the OXC system provides photonic hitless switching. These results confirm the feasibility of flexibly reconfigurable and fast-restorable OXC systems  相似文献   
7.
In this paper, a reproduction of a swing‐up and a giant swing motion of underactuated robots based on technique of the horizontal bar gymnast is discussed with focusing on an equivalent center of mass (ECM) of underactuated robots and the gymnast. At first, the behaviors of the ECM of the gymnast (ECMG) are analyzed by using a motion capturing technique and an efficient motion of the ECMG for the swing‐up and for the giant swing motion are identified from analysis results, respectively. Next, a partial linearization method, which can realize that the ECM of the Acrobot (ECMA) replicates this efficient motion, is designed and reproduces the underactuated robots the swing‐up and giant swing motion like the gymnast. Finally, an effectiveness of the proposed controller is shown by numerical simulations.  相似文献   
8.
A displacement magnification mechanism which uses flexure motion guide using elastic hinges can realize smooth frictionless motion but has poor vibration damping capability. An impact damper is a damping mechanism which uses collision energy to dissipate vibration energy. If the damper is used for vibration control of the flexure mechanism, it may be able to dissipate unexpected vibration without killing the merits of the flexure mechanism. In the paper, a loading type impact damper is applied to settle down transient vibration of a displacement magnification mechanism. We investigate differences of damping effect by setting conditions of the damper. It is shown that the impact damper can eliminate residual vibration at step response effectively without steady state error. The experimental displacement magnification mechanism with impact damper can settle down less than 1/5 of the response without the damper under appropriate setting conditions. Influence of natural frequency ratio between damper and displacement magnification mechanism is investigated. Influences of indentation at impact point are also examined.  相似文献   
9.
We designed and fabricated an active gas-gap heat switch (AGGHS), which ON/OFF the heat conduction between the 1st stage (0.05–2?K) and the 2nd stage (1–4 K) of a double-stage adiabatic demagnetization refrigerator (DADR). Our design geometrically separates two components which dominates the ON or OFF performance, and achieved heat conductivity of 6?mW/K (ON) or 4?μW/K (OFF) at 2?K. The ON/OFF is controlled by a heater attached to the charcoal box to adsorb/deadsorb 4He gas inside. We introduced the AGGHS to the DADR and successfully cooled the detector stage down to 60?mK, working properly more than a year.  相似文献   
10.
Hemodynamic and oxygen-kinetic data of 16 burn patients with sepsis were analysed to explore relationship between oxygen transport pattern and clinical outcome after dopamine and dobutamine therapy. Two patterns of oxygen transport were shown in the 16 patients. Of them, ten (62.5%) had optimal DO2 and VO2 values (model I), and six (37.5%) had lower DO2 and VO2 values than the optimal (model II). All of 6 patients with model II developed lactic acidosis, septic shock and MOF and died. Two of 10 patients in model I developed MOF, only one died. The results indicate that, in burn patient with sepsis, the decreased response of DO2 and VO2 to inotropic therapy suggests failure of tissue perfusion, oxygen extraction and utilization, and may possibly predict the outcome.  相似文献   
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