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81.
Glucose-dependent insulinotropic polypeptide (GIP) exerts extra-pancreatic effects via the GIP receptor (GIPR). Herein, we investigated the effects of GIP on force-induced bone remodeling by orthodontic tooth movement using a closed-coil spring in GIPR-lacking mice (GIPRKO) and wild-type mice (WT). Orthodontic tooth movements were performed by attaching a 10-gf nickel titanium closed-coil spring between the maxillary incisors and the left first molar. Two weeks after orthodontic tooth movement, the distance of tooth movement by coil load was significantly increased in GIPRKO by 2.0-fold compared with that in the WT. The alveolar bone in the inter-root septum from the root bifurcation to the apex of M1 decreased in both the GIPRKO and WT following orthodontic tooth movement, which was significantly lower in the GIPRKO than in the WT. The GIPRKO exhibited a significantly decreased number of trabeculae and increased trabecular separation by orthodontic tooth movement compared with the corresponding changes in the WT. Histological analyses revealed a decreased number of steady-state osteoblasts in the GIPRKO. The orthodontic tooth movement induced bone remodeling, which was demonstrated by an increase in osteoblasts and osteoclasts around the forced tooth in the WT. The GIPRKO exhibited no increase in the number of osteoblasts; however, the number of osteoclasts on the coil-loaded side was significantly increased in the GIPRKO compared with in the WT. In conclusion, our results demonstrate the impacts of GIP on the dynamics of bone remodeling. We revealed that GIP exhibits the formation of osteoblasts and the suppression of osteoclasts in force-induced bone remodeling.  相似文献   
82.
Input shaping is an effective method for reducing motion-induced vibration. The majority of input-shaping theory is based on linear analysis; however, input shaping has proven effective on moderately nonlinear systems. This work investigates the effect of nonlinear crane dynamics on the performance of input shaping. Typical bridge cranes are driven using Cartesian motions and behave nearly linearly. The rotational structure of a tower crane makes nonlinearities more apparent. Nonlinear equations of motion are presented and experimentally verified. Novel command-shaping algorithms are then proposed for reducing vibration during the nonlinear slewing motions of tower cranes.  相似文献   
83.
Inorganic layered crystals such as clay minerals, layered niobates, and graphite are exfoliated in solvents to form colloidal dispersions of extremely thin inorganic nanosheets. Recently, the liquid crystal phases of these “nanosheet colloids” have been rediscovered and are attracting interest as new types of inorganic liquid crystals. The huge anisotropy of the mesogenic nanosheets compared to other liquid crystal systems is an important feature of the nanosheet liquid crystals for fundamental studies in the fields of colloid science and soft matter physics. In addition, the rich functionalities intrinsic to inorganic materials open a variety of applications such as smart colloids and composite materials with structural regularity. In this article, the recent progress of the emerging new materials of inorganic nanosheet liquid crystals is reviewed with a focus on the behaviors of each system, alignment by external field, and theoretical aspects.  相似文献   
84.
This paper investigates tool wear mechanisms of a ball end mill in cutting laser sintered material. Cutting edge temperature is measured by using a three-color pyrometer with an optical fiber. Bulk carbon steel JIS S55C is selected as the standard steel. Experimental results show that tool life in cutting sintered material is shorter than that in cutting JIS S55C. Observations by SEM show that adhesion of the work material and micro chipping are the main wear mechanisms in cutting sintered material. The corresponding cutting edge temperature shows a continuous increase as wear evolves with cutting time.  相似文献   
85.
A series of photoresponsive and full‐colored fluorescent conjugated copolymers is synthesized by combining phenylene‐ and thienylene‐based main chains with photochromic dithienylethene (DE) side chains. Solutions and cast films of the polymers exhibit various colored fluorescence in visible wavelengths of 400?700 nm corresponding to emissions of the conjugated main chain. The fluorescence is reversibly photoswitched between emission and quenching through DE photoisomerization using external stimuli from ultraviolet and visible light irradiation. The reprecipitation method with ultrasonication enables the polymers to form spherical aggregates with diameters of 20?70 nm in water. After investigating and comparing the optical properties, the resulting nanosphere solutions are assumed to exist in an intermediate state between an isolated state (i.e., in solution) and an aggregated state in cast film. The majority of the nanosphere solutions also exhibit the same photoswitchable fluorescence behavior as those in the solutions and the cast films. The results demonstrate that the visible fluorescence of the conjugated copolymers is reversibly switchable between emission and quenching using the photoisomerizing DE side chain regardless of the fluorescent colors and the polymer chain aggregation.  相似文献   
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