34 research outputs found

    Proton-switchable vapochromic behaviour of a platinum(II)-carboxy-terpyridine complex

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    We synthesized a carboxy-substituted Pt(II)-terpyridine complex, i.e. [PtCl(Hctpy)] Cl ([1H] Cl; Hctpy = 4'-carboxy-2,2': 6',2''-terpyridine), that shows interesting switchable vapochromic behaviour upon protonation/deprotonation of the carboxy group. The as-synthesized dark-blue amorphous-like solid [1H] Cl center dot 3H(2)O was converted to a yellow crystalline solid, [1H] Cl center dot H2O, upon exposure to various polar organic solvent vapours (e.g., acetonitrile, ethanol, 1-propanol, and dichloromethane), which promote the removal of water molecules. The reaction of [1H] Cl center dot 3H(2)O with aqueous ammonia afforded a deprotonated bright-yellow crystalline complex, i.e. [PtCl(ctpy)]center dot H2O (1 center dot H2O), which exhibits red luminescence with an emission maximum at 622nm. Although the colour of 1 center dot H2O was not affected by exposure to various polar organic solvent vapours, interesting vapochromic luminescence with a remarkable red-shift of the emission maximum from 622 to 652 nm was observed upon exposure to saturated water vapour to form orange crystalline 1 center dot 3.5H(2)O X-ray structural analysis revealed that the planar and neutral complex molecule 1 forms a one-dimensional columnar structure with an intermolecular Pt center dot center dot center dot Pt distance of 3.518(2) angstrom in the orange crystall 1 center dot 3.5H(2)O, while the cationic molecule [1H](+) in the protonated form, [1H] Cl center dot H2O, generates a dimeric structure with an intermolecular Pt center dot center dot center dot Pt distance of 3.439(2) angstrom. This difference suggests that the vapochromic behaviours of the protonated and deprotonated forms could be caused by structural changes induced by water-vapour adsorption/desorption, which affect the intermolecular Pt. Pt distance, thereby changing the energy of the metal-metal-to-ligand charge-transfer (MMLCT) transition. These contrasting results for the protonated and deprotonated complexes clearly indicate that the hydrophilicity of complex 1 is significantly affected by protonation/deprotonation of the carboxy group. In addition, quasi-reversible conversion between [1H] Cl center dot 3H(2)O and 1 center dot H2O was achieved by exposure of the protonated and deprotonated forms to triethylamine and humid hydrochloric acid vapours, respectively

    Smoking cigarettes of low nicotine yield does not reduce nicotine intake as expected: a study of nicotine dependency in Japanese males

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    BACKGROUND: Many Japanese believe that low-yield cigarettes are less hazardous than regular cigarettes, and many smokers consume low-yield cigarettes to reduce their risks from smoking. We evaluate the association between actual nicotine intake and brand nicotine yield, and the influence of nicotine dependence on this association. METHODS: The study subjects included 458 Japanese male smokers, aged 51.2 ± 9.9 years, who participated in health check-ups in a hospital in 1998 and 2000. Each subject filled out a self-administered smoking questionnaire and the score of each on the Fagerström Test for Nicotine Dependence was calculated. Urinary cotinine concentration was measured at the time of participation. RESULTS: The geometric mean of urinary cotinine concentration was 535 ng/mgCr for those who smoked brands with the lowest nicotine (0.1 mg on the package), compared with 1010 ng/mgCr for those who smoked brands with the highest (0.9–2.4 mg, weighted mean of 1.1 mg). Thus, despite the 11-fold ratio of nicotine yield on the packages, the ratio of urinary cotinine level was less than twofold. Both nicotine yield on the package and nicotine dependence significantly increased urinary cotinine concentration, and the negative interaction between them almost attained statistical significance. Cotinine concentration in heavily dependent smokers was consistently high regardless of the nicotine yield of brands. CONCLUSIONS: The nicotine yield of cigarettes measured by machine-smoking does not reliably predict the exposure of smokers. Smokers consuming low-yield nicotine cigarettes did not reduce actual intake of nicotine to the level that might be expected, especially for those heavily dependent on nicotine. Current labeling practices are misleading for the two-third of smokers who are moderately or highly dependent on nicotine

    Factors associated with influenza vaccination status of residents of a rural community in Japan

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    <p>Abstract</p> <p>Background</p> <p>The rate of influenza vaccination in Japan has declined over the past several decades. It is essential to identify community-specific factors that affect attitudes toward vaccination, but such parameters have not yet been fully determined in Japan. The present study used the Health Belief Model (HBM) to identify perceptions of influenza vaccination in a rural Japanese community.</p> <p>Methods</p> <p>All subjects were residents of a rural town in the southern part of Kyoto, Japan. An anonymous self-administered questionnaire was mailed to 846 randomly chosen households (containing 2,665 subjects). The survey explored gender, age, history of influenza, and factors associated with obtaining influenza vaccination, based on the HBM.</p> <p>Results</p> <p>A total of 1,182 valid responses (response rate, 44.4%) were received. Sources of information that were associated with vaccination decisions were medical facilities for children (OR = 4.21; 95% CI: 1.17-15.1), workplaces for adults (OR = 2.40; 95% CI: 1.22-4.75), medical facilities, town office and family for elderly subjects (OR = 6.18; 95% CI: 2.42-15.7, OR = 5.59; 95% CI: 2.26-13.8 and OR = 3.29; 95%CI: 1.01-10.6). Subjects, in all age groups, who strongly agreed that the vaccine was effective were significantly more likely to be vaccinated (OR = 10.5; 95%CI: 2.68-41.7 for children; OR = 8.85; 95%CI: 4.61-16.9 for adults; OR = 19.9; 95%CI: 8.28-48.0 for the elderly). The vaccination rate of elderly subjects who expressed concerns regarding adverse vaccine effects (OR = 0.34, 95% CI: 0.15-0.78) or who were worried about practical barriers to the vaccination process (OR = 0.13; 95% CI: 0.05-0.31) was significantly lower than in other populations.</p> <p>Conclusions</p> <p>Our results indicate that vaccination coverage can be increased if accurate information on personal risk, severity of influenza illness, and efficacy of vaccination are provided by responsible information sources that are easily accessible. Such sources include medical facilities and municipal offices. In addition, barriers and inconveniences associated with vaccination should be removed, especially if they impact on elderly people.</p

    TRY plant trait database – enhanced coverage and open access

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    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    都市部の妊娠期・出産後の女性の喫煙と食生活および生活習慣との関連

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    都市部に在住する乳児の母親を対象として,妊娠前後の喫煙の現状と食・生活習慣との関連を明らかにすることを目的に,無記名自記式アンケート調査を実施した。対象は,平成14年11月の1ヶ月間に,京都市内14ヶ所の保健所・支所にて,生後4ヶ月児健診を受診した991名の乳児の母親である。喫煙や食・生活習慣に関する調査紙を手渡し,回答が得られた466名(回収率47.0%)を解析対象とした。その結果,妊娠前喫煙率は28.5%で,年齢が若いほど喫煙率が高かった。妊娠を契機に74.4%が禁煙し,妊娠中喫煙率は7.3%であったが,出産後喫煙率は10.9%に増加していた。喫煙者は非喫煙者と比較して,食・生活習慣,授乳,喫煙に関する知識の欠如などの健康課題を有しており,小児期からの喫煙防止教育等,総合的な保健対策が望まれる

    Two-way vapochromism of a luminescent platinum(II) complex with phosphonic-acidfunctionalized bipyridine ligand

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    A luminescent Pt(II) complex [Pt(CN)(2)(H(4)dpbpy)] (1P; H(4)dpbpy = 2,2'-bipyridine-4,4'-diphosphonic acid) bearing a phosphonic-acid-functionalized bipyridine ligand was successfully synthesized and its unique two-way vapochromic behaviour investigated. X-ray structure analyses of both the anhydrous 1P and penta-hydrated 1P.5H(2)O phases clearly reveal the activation of intermolecular Pt. Pt interactions through the adsorption of water vapour. Emission spectroscopy reveals that the penta-hydrated 1P.5H(2)O complex exhibits an orange emission at 585 nm that shifts in two directions, to a blue-green emission at 469 nm by drying at 100 degrees C or to a red emission at 701 nm by drying under vacuum at room temperature. Thermogravimetric analyses and powder X-ray diffraction studies clearly reveal that anhydrous 1P, with negligible intermolecular Pt. Pt interactions, is formed by drying at 100 degrees C whereas the monohydrate 1P.H2O phase, with effective Pt. Pt interactions, is formed by drying under vacuum

    Vapochromic luminescent proton conductors: switchable vapochromism and proton conduction of luminescent Pt(ii) complexes with proton-exchangeable sites

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    Two luminescent and highly proton-conductive Pt(ii) complexes [PtCl(tpypy)]Cl and [PtCl(tpypyH)]Cl-2 (1 and 1 center dot HCl, respectively; tpypy = 2,2 ': 6 ',2 ''-terpyridine-4 ',4 '''-pyridine) were successfully synthesized. X-ray analysis revealed that the intermolecular PtMIDLINE HORIZONTAL ELLIPSISPt interaction was ineffective in the monohydrated form of 1 center dot H2O but effective in dihydrate and hexahydrate forms, 1 center dot HCl center dot nH(2)O (n = 2 and 6). Yellow luminescence (lambda(em) = 519 nm and phi = 0.016) assigned to intraligand (3)pi-pi* phosphorescence was observed for 1 center dot H2O, whereas a stronger red emission ascribable to the phosphorescence from the triplet metal-metal-to-ligand charge transfer ((MMLCT)-M-3) state was observed for the HCl adduct 1 center dot HCl center dot nH(2)O (lambda(em) = 741 nm, phi = 0.06 for n = 2, lambda(em) = 642 nm, and phi = 0.10 for n = 6). Both complexes exhibited strong relative humidity (RH)-dependent proton conductivity, while surprisingly high conductivity was observed for 1 center dot HCl (6.8 x 10(-3) S cm(-1)) at 95% RH at 298 K. The reversible transformation between 1 and 1 center dot HCl was achieved upon exposure to humid HCl gas and heating and their vapochromic behaviour was completely different owing to the presence of acidic N-H protons and the additional hydrophilic Cl- counter anions in 1 center dot HCl. To the best of our knowledge, these complexes are the first switchable vapochromic and highly proton conductive materials that can be employed to visualize the proton conducting state by colour and luminescence
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