1,767 research outputs found

    Cleavage of Ge–S and C–H bonds in the reaction of electron-deficient [Os₃(CO)₈(μ-H)(μ₃-Ph₂PCH₂P(Ph)C₆H₄)] with Ph₃GeSPh: Generation of thiophenol derivatives [Os₃(CO)₈(μ-H)(μ-SPh)(μ-dppm)] and [Os₃(CO)₇(μ-H)(μ-SPh)(μ₃-SC₆H₄)(μ-dppm)]

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    Heating the electron-deficient [Os₃(CO)₈(μ-H)(μ₃-Ph₂PCH₂P(Ph)C₆H₄)] (1) and Ph₃GeSPh in benzene at 80 °C led to the thiolato bridged compounds, [Os₃(CO)₈(μ-H)(μ-SPh)(μ-dppm)] (2) and [Os₃(CO)₇(μ-H)(μ-SPh)(μ₃-SC₆H₄)(μ-dppm)] (3), formed by cleavage of Ge–S and C–S bonds of the ligand, in 40% and 17% yields, respectively. Both compounds 2 and 3 have been characterized by a combination of elemental analysis, infrared and ¹H NMR spectroscopic data together with single crystal X-ray crystallography. Compound 3 contains an open triangle of osmium atoms bridged by a SPh and SC₆H₄ ligands on opposite sides of the cluster with a dppm ligand bridging one of the Os–Os edges. Compound 2 consists of a closed triangular cluster of osmium atoms with a bridging SPh, and a bridging hydride ligand on the same Os–Os edge, and a dppm ligand bridging one of the remaining Os–Os edges

    Comparing primary prevention with secondary prevention to explain decreasing Coronary Heart Disease death rates in Ireland, 1985-2000.

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    BACKGROUND: To investigate whether primary prevention might be more favourable than secondary prevention (risk factor reduction in patients with coronary heart disease(CHD)). METHODS: The cell-based IMPACT CHD mortality model was used to integrate data for Ireland describing CHD patient numbers, uptake of specific treatments, trends in major cardiovascular risk factors, and the mortality benefits of these specific risk factor changes in CHD patients and in healthy people without recognised CHD. RESULTS: Between 1985 and 2000, approximately 2,530 fewer deaths were attributable to reductions in the three major risk factors in Ireland. Overall smoking prevalence declined by 14% between 1985 and 2000, resulting in about 685 fewer deaths (minimum estimate 330, maximum estimate 1,285) attributable to smoking cessation: about 275 in healthy people and 410 in known CHD patients. Population total cholesterol concentrations fell by 4.6%, resulting in approximately 1,300 (minimum estimate 1,115, maximum estimate 1,660) fewer deaths attributable to dietary changes(1,185 in healthy people and 115 in CHD patients) plus 305 fewer deaths attributable to statin treatment (45 in people without CHD and 260 in CHD patients). Mean population diastolic blood pressure fell by 7.2%, resulting in approximately 170 (minimum estimate 105, maximum estimate 300) fewer deaths attributable to secular falls in blood pressure (140 in healthy people and 30 in CHD patients), plus approximately 70 fewer deaths attributable to antihypertensive treatments in people without CHD. Of all the deaths attributable to risk factor falls, some 1,715 (68%) occurred in people without recognized CHD and 815(32%) in CHD patients. CONCLUSION: Compared with secondary prevention, primary prevention achieved a two-fold larger reduction in CHD deaths. Future national CHD policies should therefore prioritize nationwide interventions to promote healthy diets and reduce smoking

    Climate change and public health situations in the coastal areas of Bangladesh

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    This study aims to investigate the population health of climate change affected people in the coastal areas of Bangladesh. The relationship between climate change and health lacks clarity in the existing literature. This study uses data collected from the area affected by cyclone Sidr in 2009. Results show that climate change triggered natural disasters such as Sidr can is affect the physical and mental health of this population. The prevalence of diarrhoea, skin diseases, dengue fever, hepatitis (jaundice) and other infectious diseases has increased after the natural disaster. The risk of injury and death also increased during the time of natural disaster. Children and older adults are the most vulnerable groups facing serious health problems including mental health. The majority of the health professionals, service providers and local community of coastal areas are more aware of the health impacts of climate change, yet their knowledge is limited regarding health protection measures

    Climate change impact: the experience of the coastal areas of Bangladesh affected by cyclones Sidr and Aila

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    Bangladesh is considered one of the countries most at risk to the effects of climate change and its coastal area is most vulnerable. This study tries to explore the experiences of cyclones Sidr and Aila affected people living in the coastal areas of Bangladesh. This study was conducted in the cyclone Sidr affected Amtali Upazila of Barguna District and in the cyclone Aila affected Koyra Upazila of Khulna District. Primary data collection was done using Focus Group Interview and then a thematic analysis approach was used for analysis. Three core themes emerged from the analysis and they are, firstly, impacts of climate change on the socioeconomic condition of the people, secondly, the impact on the health status of the population, and finally the impact on vulnerable people. Findings show that the effects of climate change have serious consequences on the livelihood patterns of the affected population and on their overall health status. As a result, the unfavorable health condition of these affected people makes them more vulnerable to various emerging diseases

    Ruthenium and osmium carbonyl clusters incorporating stannylene and stannyl ligands

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    The reaction of [Ru₃ (CO)₁₂] with Ph₃SnSPh in refluxing benzene furnished the bimetallic Ru-Sn compound [Ru₃(CO)₈(μ-SPh)₂(μ3-SnPh₂)(SnPh₃)₂] 1 which consists of a SnPh₂ stannylene bonded to three Ru atoms to give a planar tetra-metal core, with two peripheral SnPh₃ ligands. The stannylene ligand forms a very short bond to one Ru atom [Sn-Ru 2.538(1) Å] and very long bonds to the other two [Sn-Ru 3.074(1) Å]. The germanium compound [Ru₃(CO)₈(μ-SPh)₂(μ₃-GePh₂)(GePh₃)₂] 2 was obtained from the reaction of [Ru₃ (CO)₁₂] with Ph₃GeSPh and has a similar structure to that of 1 as evidenced by spectroscopic data. Treatment of [Os₃(CO)₁₀(MeCN)₂] with Ph₃SnSPh in refluxing benzene yielded the bimetallic Os-Sn compound [Os₃(CO)₉(μ-SPh)(μ₃-SnPh₂)(MeCN)(ƞ¹-C₆H₅)] 3. Cluster 3 has a superficially similar planar metal core, but with a different bonding mode with respect to that of 1. The Ph₂Sn group is bonded most closely to Os(2) and Os(3) [2.7862(3) and 2.7476(3) Å respectively] with a significantly longer bond to Os(1), 2.9981(3) Å indicating a weak back-donation to the Sn. The reaction of the bridging dppm compound [Ru₃(CO)₁₀(μ-dppm)] with Ph₃SnSPh afforded [Ru₃(CO)₆(μ-dppm)(μ₃-S)(μ₃-SPh)(SnPh₃)] 5. Compound 5 contains an open triangle of Ru atoms simultaneously capped by a sulfido and a PhS ligand on opposite sides of the cluster with a dppm ligand bridging one of the Ru-Ru edges and a Ph₃Sn group occupying an axial position on the Ru atom not bridged by the dppm ligand

    Karakterisasi Morfologi dan Anatomi Aksesi Mangga Dodor (Mangifera SP.) di Kecamatan Sindue Kabupaten Donggala

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    Mango (Mangifera indica), is a fruit that comes from India, it has many varieties. Mangoes are generally marketed in the form of fresh, both for domestic and export purposes. The objectives of this study were to assess the accession mango dodor in Lembah Palu through characterization of morphological and anatomical Toaya and Lero Village Donggala District. The research method using accessibility method by observing plant morphology character was continued with characterization of diversity using cluster analysis using systat software 0.8. The results showed that there were several different accessions in each village in Sindue subdistrict based on morphological and anatomical characteristics.The different accessions in Toaya Village at a distance of 0.6 were obtained TF11, TF9, TF14. Lero village have different accessions, namely LR6, LR14, and LR13 and in Sindue sub-districts TF9, LR6, and LR15

    An electron-deficient triosmium cluster containing the thianthrene ligand: Synthesis, structure and reactivity of [Os₃(CO)₉(μ3-η2-C₁₂H₇S₂)(μ-H)]

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    Reaction of [Os₃(CO)₁₀(CH₃CN)₂] with thianthrene at 80 °C leads to the nonacarbonyl dihydride compound [Os₃(CO)₉(μ-3,4-η²-C₁₂H₆S₂)(μ-H)₂] (1) and the 46-electron monohydride compound [Os₃(CO)₉(μ₃-η²-C₁₂H₇S₂)(μ-H)] (2). Compound 2 reacts reversibly with CO to give the CO adduct [Os₃(CO)₁₀(μ-η²-C₁₂H₇S₂)(μ-H)] (3) whereas with PPh₃ it gives the addition product [Os₃(CO)₉)(PPh₃)(μ-η²-C₁₂H₇S₂)(μ-H)] (4) as well as the substitution product 1,2-[Os₃(CO)₁₀ ((PPh₃)₂] (5) Compound 2 represents a unique example of an electron-deficient triosmium cluster in which the thianthrene ring is bound to cluster by coordination of the sulfur lone pair and a three-center-two-electron bond with the C(2) carbon which bridges the same edge of the triangle as the hydride. Electrochemical and DFT studies which elucidate the electronic properties of 2 are reported

    Potential impact and controversy of stem cells in public health

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    Stem cells are versatile in the bodies which are able to both reproduce themselves and to produce more specialized cells. As such, they are of great potential values in repairing and regenerating damaged cells and tissues. Many different kinds of stem cells have been discovered. The most common are embryonic, foetal and adult stem cells. Stem cell research has the potential to provide an increased understanding of development and differentiation, as well as leading to treatments and cures for many diseases. They are important to the future of medicine and public health because with adequate research, stem cells have the potential to treat degenerative conditions through transplanting human stem cells into patients. With sufficient development of stem cell medicine, chronic diseases such as diabetes, heart disease, and Parkinson’s disease will be effectively managed. Embryonic stem cell (ESC) research has been a source of ethical, legal, and social controversy which has slowed the pace of stem cell science and shaped many aspects of its subsequent development

    Ionization Potential of the Helium Atom

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    Ground state ionization potential of the He^4 atom is evaluated to be 5 945 204 221 (42) MHz. Along with lower order contributions, this result includes all effects of the relative orders alpha^4, alpha^3*m_e/m_alpha and alpha^5*ln^2(alpha).Comment: 4 page

    Tetranuclear Group 7/8 Mixed-Metal and Open Trinuclear Group 7 Metal Carbonyl Clusters Bearing Bridging 2-mercapto-1-methylimidazole Ligands

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    The reactivity of group 7 metal dinuclear carbonyl complexes [M2(CO)6(μ-SN2C4H5)2] (1, M = Re; 2, M = Mn) toward group 8 metal trinuclear carbonyl clusters were examined. Reactions of 1 and 2 with [Os3(CO)10(NCMe)2] in refluxing benzene furnished the tetranuclear mixed-metal clusters [Os3Re(CO)13(μ3-SN2C4H5)] (3) and [Os3Mn(CO)13(μ3-SN2C4H5)] (4), respectively. Similar treatment of 1 and 2 with Ru3(CO)12 yielded the ruthenium analogs [Ru3Re(CO)13(μ3-SN2C4H5)] (5), and [Ru3Mn(CO)13(μ3-SN2C4H5)] (6), but in the case of 2 a secondary product [Mn3(CO)10(μ-Cl)(μ3-SN2C4H5)2] (7) was also formed. Compounds 3–6 have a butterfly core of four metal atoms with the M (Mn or Re) at a wingtip of the butterfly and containing a noncrystallographic mirror plane of symmetry. This result provides a potential method for the synthesis of a series of new group 7/8 mixed metal complexes containing a bifunctional heterocyclic ligand. Compound 7 is a unique example of a 54-electron trimanganese complex having bridging 2-mercapto-1-methylimidazolate and chloride ligands. Interestingly, the reaction of 1 with Fe3(CO)12 at 70–75 °C furnished the tri- and dirhenium complexes [Re3(CO)10(μ-H)(μ3-SN2C4H5)2] (8) and [Re2(CO)6(N2C4H5)(μ-SN2C4H5)2] (9), respectively instead of the expected formation of the mixed-metal clusters. The former is an interesting example of a 52-electron trirhenium-hydridic complex containing bridging 2-mercapto-1-methylimidazolate ligand, while the latter can be viewed as a 1-methylimidazole adduct of 1. No mixed Fe–Re complexes were produced in this reaction. The molecular structures of the new compounds 3–5 and 7–9 were established by single-crystal X-ray diffraction analyses and the DFT studies of compounds 5, 7 and 8 are reported
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