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Aims: Coping strategies may be significantly associated with health outcomes. This is the first study to investigate the association between baseline coping strategies and cardiovascular disease (CVD) incidence and mortality in a general population cohort., Methods and Results: The Japan Public Health Center-based prospective Study asked questions on coping in its third follow-up survey (2000-04). Analyses on CVD incidence and mortality included 57 017 subjects aged 50-79 without a history of CVD and who provided complete answers on approach- and avoidance-oriented coping behaviours and strategies. Cox regression models, adjusted for confounders, were used to determine hazard ratios (HRs) according to coping style. Mean follow-up time was 7.9 years for incidence and 8.0 years for mortality.The premorbid use of an approach-oriented coping strategy was inversely associated with incidence of stroke (HR = 0.85; 95% CI, 0.73-1.00) and CVD mortality (HR = 0.74; 95% CI, 0.55-0.99). Stroke subtype analyses revealed an inverse association between the approach-oriented coping strategy and incidence of ischaemic stroke (HR = 0.79; 95% CI, 0.64-0.98) and a positive association between the combined coping strategy and incidence of intra-parenchymal haemorrhage (HR = 2.03; 95% CI, 1.01-4.10). Utilizing an avoidance coping strategy was associated with increased mortality from ischaemic heart disease (IHD) only in hypertensive individuals (HR = 3.46; 95% CI, 1.07-11.18). The coping behaviours fantasizing and positive reappraisal were associated with increased risk of CVD incidence (HR = 1.24; 95% CI, 1.03-1.50) and reduced risk of IHD mortality (HR = 0.63; 95% CI, 0.40-0.99), respectively., Conclusion: An approach-oriented coping strategy, i.e. proactively dealing with sources of stress, may be associated with significantly reduced stroke incidence and CVD mortality in a Japanese population-based cohort., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

An understanding of the dissolution process of cellulose derivatives is important not only for basic research but also for industrial purposes. We investigated the dissolution process of cellulose triacetate II (CTA II) nano-sized crystal in DMSO solvent using molecular dynamics simulations. The nano-sized crystal consists of 18 CTA chains. During the 9 ns simulation, it was observed that one chain (C01) located at the corner of the lozenge crystal was solvated by the DMSO molecules and moved away from the remaining cluster into the DMSO solvent. The analysis showed that the breakage of the interaction between the H1, H3, and H5 hydrogens of the pyranose ring and the acetyl carbonyl oxygen in the C01 and C02 adjacent chains would be crucial for the dissolution of CTA. The DMSO molecules solvating around these atoms would prevent the re-crystallization of the CTA molecules and facilitate further dissolution., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Phase separation phenomena of aqueous suspensions of cellulose nanocrystals have been studied for bacterial cellulose (BC) prepared by sulfuric acid hydrolysis. Suspensions at concentrations above 0.42 wt % separated into the isotropic and chiral nematic phases with a clear phase boundary. The shape and size distribution of BC nanocrystals in both the phases were determined by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The surface charge density was determined by conductometric titration. The effects of added NaCl (0-5.0 mM) on the phase separation behavior of the aqueous suspensions were investigated for a fixed total cellulose concentration. The volume fraction of the chiral nematic phase had a minimum value at a NaCl concentration of ca. 1.0 mM. At NaCl concentrations ranging from 2.0 to 5.0 mM, the suspensions did not separate into two phases, but became entirely liquid crystalline. The size of the ordered domains in the anisotropic phase decreased with an increase in the NaCl concentration from 0 to 2.75 mM. At 2.75 mM, only tactoids were observed in the entire region. At 5.0 mM, chiral nematic domains were no longer observed. The chiral nematic pitch decreased with increasing concentration of added NaCl, reached a minimum value at approximately 0.75 mM, and then increased sharply with the NaCl concentration up to 2.0 mM.

Curious low-temperature solubility of cellulose triacetates (CTA; here we use nominally "CTA," but the sample still contains 7% of C-6 position hydroxyls) in an organic solvent, methyl acetate (MA), was studied by a newly designed low-temperature type of DLS apparatus, which enabled for the first time to investigate the structural change of CTA in solution from 45 degrees C down to -100 degrees C. A molecularly dissolved CTA was found to coexist with three types of self-assemblies over all the temperature ranges except for the three specific temperatures T* of 30, -10, and -75 degrees C. However, these multiple self-assemblies are not in real thermodynamic equilibrium but in a metastable state, which could be stabilized effectively by the intermolecular hydrogen bonding (HB) with the help of the dipole interaction at low temperatures. In more detail, with decreasing temperature, these assemblies performed the structural reorganization drastically at three T*'s and would finally be frozen in a physical gel structure at -99 degrees C; around the freezing temperature of MA, CTA molecules could be trapped homogeneously in the frozen MA. The crucial role in such structural reorganizations is played by the balance between the intermolecular HB and the dipole interaction worked in the highly electronegative solvent. Because these interactions, which are mediated by the solvent electronegativity, change drastically with temperature, they result in the control of not only the single CTA chain conformation (= the intramolecular HB) but also the binding ways of the intermolecular HBs between CTA molecules and they induce multitudinous metastable structures in solution. Here it is noted that HB could work mainly between the C-6 position hydroxyls in the anhydroglucose units of CTA and are essentially effective at low temperatures.

The isomeric states and intermolecular packing of tris(8-hydroxyquinoline) aluminum(III) (Alq(3)) in the alpha-, gamma-, and delta-crystalline forms and in the amorphous state, which are important for understanding the light-emitting and electron-transport properties, have been analyzed by CP/MAS (13)C NMR. This simple NMR experiment shows that the isomeric state of alpha- and amorphous Alq(3) is meridional, whereas that of gamma- and delta-Alq(3) is facial. In the amorphous Alq(3), the inclusion of facial isomers has been under debate. Our experiments show that meridional isomers are dominant in the amorphous Alq(3), although the existence of facial isomers cannot be completely denied. The local structure of amorphous Alq(3) is similar to that of alpha-Alq(3) and is significantly different from those of gamma- and delta-Alq(3). Among these Alq(3) samples, the effect of intermolecular interaction is not found only for gamma-Alq(3). This finding can explain the good solvent solubility of gamma-Alq(3), compared with the other crystalline forms. It is also shown that the structures are locally disordered not only for amorphous Alq(3) but also for alpha-Alq(3), although clear X-ray diffraction peaks are observed for alpha-Alq(3). In contrast, the local structures of gamma- and delta-Alq(3) are well defined. A clear relation is found between the spectral patterns of CP/MAS (13)C NMR and the fluorescence wavelengths; the samples, which consist of facial isomers, show blue-shifted fluorescence compared with those of meridionals.

Stable suspensions of tunicate cellulose microfibrils were prepared by acid hydrolysis of the cellulosic mantles of tunicin. They formed a chiral nematic phase above a critical concentration. External magnetic fields were applied to the chiral nematic phase in two different manners to control its phase structure. (i) Static magnetic fields ranging 1-28 T were used to align the chiral nematic axis (helical axis) in the field direction. (ii) A rotating magnetic field (5 T, 10 rpm) was applied to unwind the helices and to form a nematic phase. These phenomena were interpreted in terms of the anisotropic diamagnetic susceptibility of the cellulose microfibril. The diamagnetic susceptibility of the microfibril is smaller in the direction parallel (chi( parallel)) to the fiber axis than in the direction perpendicular (chi( perpendicular)) to the fiber axis, that is, chi( parallel) < chi( perpendicular) < 0. Because the helical axis coincides with the direction normal ( perpendicular) to the fiber axis, the helical axis aligned parallel to the applied field. On the other hand, the rotating magnetic field induced the uniaxial alignment of the smallest susceptibility axis, that is, chi( parallel) in the present case, and brought about unwinding of the helices.

We succeeded in estimating the thickness of band-like cellulose assemblies by combined use of atomic force microscopy (AFM) and transmission electron microscopy. The thickness of "dense" band-like cellulose assemblies was estimated at 20-30 nm from their AFM height profiles, which was several times greater than that of "coarse" band-like and ribbonlike cellulose assemblies. On the basis of these results, the folded- chain model previously proposed was discussed, and a different organization of TC subunits was suggested for the "dense" band-like cellulose assembly.

To obtain further information about the cause for the rather large splitting of the C4 resonance line into the downfield (C4D) and upfield (C4U) lines in CP/MAS 13C NMR spectra for native cellulose, 13C and 1H spin diffusion measurements have been conducted by using different types of bacterial cellulose samples. In 13C spin diffusion measurements, the C4D resonance line is selectively inverted by the Dante pi pulse sequence and the 13C spin diffusion is allowed to proceed from the C4D carbons to other carbons including the C4U carbons with use of the 13C4-enriched bacterial cellulose sample. The analysis based on the simple spin diffusion theory for the process experimentally observed reveals that the C4U carbons may be located at distances less than about 1 nm from the C4D carbons. In 1H spin diffusion measurements, poly(vinyl alcohol) (PVA) films in which ribbon assemblies of bacterial cellulose are dispersed are employed and the 1H spin diffusion process is examined from the water-swollen PVA continuous phase to the dispersed ribbon assemblies by the 13C detection through the 1H-13C CP technique. As a result, it is found that the C4D and C4U carbons are almost equally subjected to the 1H spin diffusion from the PVA phase, indicating that the C4U carbons are not localized in some limited area, e.g. in the surfacial region, but are distributed in the whole area in the microfibrils. These experimental results suggest that the C4U carbons may exist as structural defects probably due to conformational irregularity associated with disordered hydrogen bonding of the CH(2)OH groups in the microfibrils.

Dynamics of cellulose diacetate (CDA, the total degree of substitution (TDS) = 2.44) in dimethylacetamide (DMAc) in dilute solution was investigated at 2, 10, 20, 30, 40, 49.7, and 61.5 degrees C through dynamic light scattering in the quiescent state. The following three facts were made clear. First, CDA existed in three types of structures in the polar solvent, DMAc; one is a single CDA chain, and the others are dynamic structures, or self-assemblies, which were formed temporarily and locally by the solvent-mediated hydrogen bonding between the intermolecular C-6 position hydroxyls of the anhydroglucose units in the CDA backbone. Second, CDA showed a nature of low-temperature solubility in DMAc, that is, CDA is expected to dissolve molecularly below -12 degrees C but to take a phase separation above 65 degrees C, where two structures such as collapses of a single CDA chain and an aggregate appear. Third, a reorganization in the dynamic structures was detected at the temperature T = 33.8 degrees C. At this temperature, two dynamic structures showed the discontinuity in their correlation lengths, whereas the single CDA realized an uncorrelated chain state in the dynamical sense. In view of the low-temperature solubility of CDA in DMAc, this abnormal behavior around T was explained by dynamical critical-like fluctuations if T were treated as a kind of lower critical solution temperature (LCST) in the CDA/DMAc system. Here, the self-assemblies arise as the dynamical fluctuations under the spinodal decomposition situation and the competition between the hydrogen bonding (HB) and the hydrophobic interaction (HPhI) makes the conformation of CDA chains change drastically. In this scheme, the solvent-mediated HB and HPhI play important roles in the structure reorganization of cellulose derivatives in strong electronegative solvents, though HB and HPhI cooperate with the inherent chain helicality.

Two kinds of regioselectively substituted cellulose derivatives, i.e., 6-O-triphenylmethylcellulose (6TC) and 2,3-di-O-acetyl-6-O-triphenylmethylcellulose (2,3Ac6TC), were prepared via cellulose. In these samples, C-6 position hydroxyls in the anhydroglucose units (AGU) along the cellulose chain were selectively substituted by the hydrophobic triphenylmethyl groups, but C-2 and -3 position hydroxyls remained in 6TC or were substituted completely by O-acetyls in 2,3Ac6TC. Their chain dynamics in polar solvents, dimethyl sulfoxide (DMSO) and N,N-dimethylacetamide (DMAc), in dilute solution were investigated by dynamic light scattering in the viewpoint of cluster formation. The results were compared with those of cellulose diacetates (CDA) in DMAc where three hydroxyls in the AGU were statistically substituted up to 2.44 by O-acetyls but hydroxyls at C-6 positions remained predominantly. It was found that 6TC and 2,3Ac6TC formed a dynamic structure about 10 times larger than single chains and that the structure would be a temporary and local association due to concentration fluctuations (dynamic structures) which were originated from the hydrophobic interactions between intermolecular triphenylmethyl groups. The dynamics and structures were in clear contrast to those of CDA where a solvent-mediated hydrogen bonding between intermolecular C-6 position hydroxyls was essential to cluster formation. The present structures were so weak as to dissipate easily under low shear field.

Molecular dynamics has been studied by broadband dielectric relaxation spectroscopy in the Sm-A, Sm-B, and Sm-E phases (Sm denotes smectic) of a homologous series of nonchiral stilbenes. An assignment of modes is presented based on their dependence on temperature and molecular length, and, as far as they obey the Arrhenius law, their activation energy has been determined. In general, reorientations of entire molecules around their short axis are active, whereas reorientations of entire molecules around their long axis are locked out in the Sm-E phase of shorter homologs, yet intramolecular reorientations of polar sites have been established. Strong evidence is presented for an interdependence of reorientations of entire molecules around the short and long axes within the biaxial Sm-E phase of longer homologs.

Crystalline features of cellulose microfibrils in the cell walls of Glaucocystis (Glaucophyta) were studied by combined spectroscopy and diffraction techniques, and the results were compared with those of Oocystis (Chlorophyta). Although these algae are grouped into two different classes, by the composition of their chloroplasts for instance, their cell walls are quite similar in size and morphology. The most striking features of their cellulose crystallites are that they have the highest cellulose I(alpha) contents reported to date. In particular, the I(alpha) fraction of cellulose from Glaucocystis was found to be as high as 90% from (13)C NMR analysis. The mode of preferential orientation of cellulose crystallites in their cell walls is also interesting; equatorial 0.53-nm lattice planes were oriented parallel to the cell surface in the case of Glaucocystis, while the 0.62-nm planes were parallel to the Oocystis cell surface. Such a structural variation provides another link to the evolution of cellulose structure, biosynthesis, and its biocrystallization mechanism., (Copyright 1999 Academic Press.)

The cyanogen bromide (CNBr) activation method was adopted to link collagen molecules onto the surface of cellulose and poly(vinyl alcohol) (PVA) films via covalent bonding. The amount of bound protein was determined by the ninhydrin method and found to be 1.0 microgram/cm2 for the native collagen and 0.6 microgram/cm2 for the denatured collagen. The amount of bound protein was larger for cellulose than PVA. When p-toluene-sulphonyl chloride was used to activate the cellulose film, this activation method was found to be effective in grafting the collagen as well. The cellulose film was found to become brittle and weak after activation with CNBr, but the PVA films was not. This might be due to the difference in the extent of crosslinking between cellulose and PVA films, as demonstrated by the change in degree of swelling and solubility of both the activated films.

Blood compatibility has been studied for hydrophilic polymers such as poly(vinyl alcohol) (PVA), its derivative, and polyethylene grafted with water-soluble monomers. The surfaces in contact with electrolyte solutions have been characterized by measuring the zeta potentials. The study of plasma protein adsorption on these polymers has revealed that bovine serum albumin as well as bovine serum fibrinogen adsorbs to a lesser extent as the hydrophilicity of the polymers increases. Platelet deposition and fibrin formation, examined using platelet-rich plasma, have been found to take place less significantly on PVA as well as sodium acrylate- and acrylamide-grafted polyethylene than on nongrafted and acrylic acid-grafted polyethylene. Ex vivo experiments with canine whole blood have shown that formation of thrombus on PVA is less than on siliconized glass but increases upon heat treatment which reduces the hydrophilicity. When PVA tubes of about 1 mm diameter are anastomosed to the carotid artery of rat, the patency rate is found to depend strongly on the anastomotic technique. From the results on the zeta potential and the experiments in vitro and ex vivo it can be concluded that the material having a surface from which solvated, neutral chains are extended into the outer aqueous phase may exhibit excellent resistance to thrombus formation.