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Glycopolymers have attracted increased attention as functional polymeric materials, and simple methods for synthesizing glycopolymers remain needed. This paper reports the aqueous one-pot and chemoenzymatic synthesis of four types of glycopolymers via two reactions: the β-galactosidase-catalyzed glycomonomer synthesis using 4,6-dimetoxy triazinyl β-D-galactopyranoside and hydroxy group-containing (meth)acrylamide and (meth)acrylate derivatives as the activated glycosyl donor substrate and as the glycomonomer precursors, respectively, followed by radical copolymerization of the resulting glycomonomer and excess glycomonomer precursor without isolating the glycomonomers. The resulting glycopolymers bearing galactose moieties exhibited specific and strong interactions with the lectin peanut agglutinin as glycoclusters.  相似文献   
3.
Application of our net algorithm to the generation of all possible IPR isomers for giant fullerenes Cn, n=102 to 120, missed nine out of 39,621 possible structures. Analysis revealed that the omission of too small and too large cap triangles was the reason. Within the range of fullerenes studied, the missed structures are of high-energy and do not affect the distribution of significantly low-energy isomers.  相似文献   
4.
Over 2000 electrocution deaths were identified among U.S. construction workers from 1980 to 1991, with the highest mean annual crude mortality rate (2.5 per 100,000 people), and second highest mean age-adjusted rate (2.7 per 100,000 people) of all industries. Although the crude fatality rates showed a downward trend, construction workers are still about four times more likely to be electrocuted at work than are workers in all industries combined. Nearly 40% of the 5083 fatal electrocutions in all industries combined occurred in construction, and 80% were associated with industrial wiring, appliances, and transmission lines. Electrocutions ranked as the second leading cause of death among construction workers, accounting for an average of 15% of traumatic deaths in the industry from 1980 to 1991. The study indicates that the workers most at risk of electrical injury are male, young, nonwhite, and electricians, structural metal workers, and laborers. The most likely time of injury is 11 a.m. to 3 p.m. from June to August. Focusing prevention on these populations and characteristics through better methods of worker and supervisor electrical safety training, use of adequate protective clothing, and compliance with established procedures could minimize the average annual loss of 168 U.S. construction workers.  相似文献   
5.
A 70-year-old woman was referred to our hospital with a complaint of a soft mass at the right elbow. Venography demonstrated that the mass was connected with vein. This mass was surgically removed and histologically a marked reduction of both elastic fibers and the adventitia were observed in the aneurysmal wall. Venous aneurysm (VA) is different form varicose veins by many features. It was considered that congenital fragility of the venous walls was associated with the onset of VA. We classified VA into type-I VA (cystic ectasia) and type II (fusiform ectasia).  相似文献   
6.
The measurements of diphenylhexatriene (DPH) and trimethylammonium diphenylhexatriene (TMA-DPH) fluorescence anisotropy in egg yolk lecithin (EYL) and of DPH anisotropy in dipalmitoylphosphatidylcholine (DPPC) liposomes containing different concentrations of oxidized and reduced ubiquinone (UQ) and plastoquinone (PQ) homologues have been performed. All the oxidized UQ homologues strongly induced ordering of EYL membrane structure, whereas in DPPC liposomes, above the phase transition temperature, the most pronounced effect showed UQ-4. PQ-2 and PQ-9 were less effective than the corresponding ubiquinones in this respect. The reduced forms of UQ and PQ homologues increased the order of membrane lipids to a smaller extent than the corresponding quinones both in the interior of the membrane and closer to its surface. Nevertheless, the investigated prenylquinols showed stronger increase in the membrane order than alpha-tocopherol or alpha-tocopherol acetate, which could be connected with binding of prenylquinol head groups to phospholipid molecules by hydrogen bonds. The strong ordering influence of ubiquinones on the membrane structure was attributed to methoxyl groups of the UQ quinone rings.  相似文献   
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Initial steps of thermal transformation from doubly bonded [2+2] (1) and [4+4] (2) dimers of C60 have been analyzed on the basis of computed structural features and Pople's energy partition scheme. Completely conjugated C120 structures 3 and 4 are found to be considerably stable and proposed to be important intermediates. The linkage patterns in 3 and 4 are also likely to appear in the repeating units of the metastable dimer and polymer phases of A1 crystals.  相似文献   
9.
The authors report a rare case of a large cystic cervical neurinoma. A 45-year-old female was admitted to our clinic because of motor weakness of the right upper extremity, numbness of the right fingers and right posterior cervical pain. Metrizamide CT myelography demonstrated the outline of a low density mass. MRI showed a mass revealing low signal intensity on T1-weighted image, high signal intensity on T2-weighted image and marginal enhancement on contrast image with Gd-DTPA. The mass which was diagnosed as cystic tumor, was located in the intradural extramedullary space between C4 to C5 segments. After C4 through C5 laminectomy, the tumor was found to originate from the C5 anterior motor root. The tumor consisted mostly of a cystic part with a very thin solid compartment beneath the capsule. Postoperative course of the patient was uneventful. Although spinal neurinoma is one of the most common spinal tumors, an almost completely degenerated large cystic spinal neurinoma is extremely rare. MRI with Gd-DTPA was useful for the diagnosis of the cystic neurinoma by clearly enhancing the margin of the tumor.  相似文献   
10.
A universal guideline and state-of-the-art hot-carrier effects in scaled MOSFETs are reviewed and discussed from the viewpoints of 1) DC and AC hot-carrier effects, 2) hot-carrier detrapping phenomena, 3) mechanical stress effects on hot-carrier phenomena, and 4) hot-carrier resistant device structures.In the deep-submicron region, the hot-carrier applicable voltage is less than 3 V, so AC hot-carrier effects from the dynamic operation of actual circuits should be taken into account. Despite much experimentation and analysis, there is still no universally accepted theory that explain the AC degradation mechanism. This is because the noise caused by the wiring inductance in ULSI circuits and in measurement systems screens the intrinsic AC hot-carrier effects.Here, AC hot-carrier degradation enhanced by gate pulse-induced-noise is analyzed experimentally and theoretically. After eliminating the noise problem, it is found that AC hot-carrier degradation in LDD (Lightly doped drain) and GOLD (gate-drain overlapped device) structures can be estimated based on DC degradation in terms of the effective stress time which takes the duty ratio into account. In addition, it is found that the noise is negligible when the wiring inductance is smaller that 80 nH (250 mω), which is important for future circuit design.Furthermore, hot-carrier detrapping effects, especially in p-channel MOS devices, and hot-carrier phenomena under mechanical stress are investigated experimentally to better understand the underlying hot-carrier physics. Finally, future hot-carrier resistant device structures are discussed.  相似文献   
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